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Kelly P, Denver P, Satchell SC, Ackermann M, Konerding MA, Mitchell CA. Microvascular ultrastructural changes precede cognitive impairment in the murine APPswe/PS1dE9 model of Alzheimer's disease. Angiogenesis 2017; 20:567-580. [PMID: 28741167 PMCID: PMC5660145 DOI: 10.1007/s10456-017-9568-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 07/18/2017] [Indexed: 01/04/2023]
Abstract
Cerebral and systemic organ microvascular pathologies coexist with human Alzheimer's disease (AD) neuropathology. In this study, we hypothesised that both cerebral and systemic microvascular pathologies exist in 4- to 5-month-old male APPswe/PS1dE9 (APP/PS1) transgenic mice prior to the onset of cognitive impairment. To assess this we examined recognition memory in both wild-type and APP/PS1 mice using the object recognition task (ORT; n = 11 per group) and counted thioflavin-S-positive plaques in brain (n = 6 per group). Vascular casts of brain, liver, spleen and kidneys were examined using scanning electron microscopy (n = 6 per group), and the urinary albumin-to-creatinine ratio (uACR; n = 5 per group) was measured as an index of glomerular permeability. Murine recognition memory was intact, as demonstrated by a significant preference for the novel object in the ORT paradigm. Brain sections of wild-type mice were devoid of thioflavin-S positivity, whereas age-matched APP/PS1 mice had an average of 0.88 ± 0.22 thioflavin-S-positive plaques in the cortex, 0.42 ± 0.17 plaques in the dentate gyrus and 0.30 ± 0.07 plaques in the cornus ammonis 1 region. The profiles of casted cerebral capillaries of wild-type mice were smooth and regular in contrast to those of APP/PS1 mice which demonstrate characteristic (0.5-4.6 μm) 'tags'. APP/PS1 mice also had a significantly reduced hepatic vessel number (p = 0.0002) and an increase in the number of splenic microvascular pillars (p = 0.0231), in the absence of changes in either splenic microvascular density (p = 0.3746) or glomerular ultrastructure. The highly significant reduction in uACR in APP/PS1 mice compared to wild-type (p = 0.0079) is consistent with glomerular microvascular dysfunction. These findings highlight early microvascular pathologies in 4- to 5-month-old APP/PS1 transgenic mice and may indicate an amenable target for pharmacological intervention in AD.
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Affiliation(s)
- Patricia Kelly
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK
| | - Paul Denver
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK
| | | | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Centre, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Centre, Johannes Gutenberg-University Mainz, Mainz, Germany
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Devlin-Mullin A, Todd NM, Golrokhi Z, Geng H, Konerding MA, Ternan NG, Hunt JA, Potter RJ, Sutcliffe C, Jones E, Lee PD, Mitchell CA. Atomic Layer Deposition of a Silver Nanolayer on Advanced Titanium Orthopedic Implants Inhibits Bacterial Colonization and Supports Vascularized de Novo Bone Ingrowth. Adv Healthc Mater 2017; 6. [PMID: 28321991 DOI: 10.1002/adhm.201700033] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 02/01/2017] [Indexed: 11/10/2022]
Abstract
Joint replacement surgery is associated with significant morbidity and mortality following infection with either methicillin-resistant Staphylococcus aureus (MRSA) or Staphylococcus epidermidis. These organisms have strong biofilm-forming capability in deep wounds and on prosthetic surfaces, with 103 -104 microbes resulting in clinically significant infections. To inhibit biofilm formation, we developed 3D titanium structures using selective laser melting and then coated them with a silver nanolayer using atomic layer deposition. On bare titanium scaffolds, S. epidermidis growth was slow but on silver-coated implants there were significant further reductions in both bacterial recovery (p < 0.0001) and biofilm formation (p < 0.001). MRSA growth was similarly slow on bare titanium scaffolds and not further affected by silver coating. Ultrastructural examination and viability assays using either human bone or endothelial cells, demonstrated strong adherence and growth on titanium-only or silver-coated implants. Histological, X-ray computed microtomographic, and ultrastructural analyses revealed that silver-coated titanium scaffolds implanted into 2.5 mm defects in rat tibia promoted robust vascularization and conspicuous bone ingrowth. We conclude that nanolayer silver of titanium implants significantly reduces pathogenic biofilm formation in vitro, facilitates vascularization and osseointegration in vivo making this a promising technique for clinical orthopedic applications.
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Affiliation(s)
- Aine Devlin-Mullin
- Centre for Molecular Biosciences (CMB); School of Biomedical Sciences; Ulster University; Coleraine BT521SA UK
| | - Naomi M. Todd
- Centre for Molecular Biosciences (CMB); School of Biomedical Sciences; Ulster University; Coleraine BT521SA UK
| | - Zahra Golrokhi
- School of Engineering; University of Liverpool; Liverpool L69 3GH UK
| | - Hua Geng
- School of Materials; The University of Manchester; Oxford Rd Manchester M13 9PL UK
| | - Moritz A. Konerding
- Institute of Functional and Clinical Anatomy; Johannes Gutenberg University; Mainz 55128 Germany
| | - Nigel G. Ternan
- Centre for Molecular Biosciences (CMB); School of Biomedical Sciences; Ulster University; Coleraine BT521SA UK
| | - John A. Hunt
- Institute of Ageing and Chronic Disease; University of Liverpool; Liverpool L7 8TX UK
| | - Richard J. Potter
- School of Engineering; University of Liverpool; Liverpool L69 3GH UK
| | - Chris Sutcliffe
- School of Engineering; University of Liverpool; Liverpool L69 3GH UK
| | - Eric Jones
- School of Engineering; University of Liverpool; Liverpool L69 3GH UK
| | - Peter D. Lee
- School of Materials; The University of Manchester; Oxford Rd Manchester M13 9PL UK
| | - Christopher A. Mitchell
- Centre for Molecular Biosciences (CMB); School of Biomedical Sciences; Ulster University; Coleraine BT521SA UK
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Ackermann M, Kim YO, Wagner WL, Schuppan D, Valenzuela CD, Mentzer SJ, Kreuz S, Stiller D, Wollin L, Konerding MA. Effects of nintedanib on the microvascular architecture in a lung fibrosis model. Angiogenesis 2017; 20:359-372. [PMID: 28283856 DOI: 10.1007/s10456-017-9543-z] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 03/06/2017] [Indexed: 01/17/2023]
Abstract
Nintedanib, a tyrosine kinase inhibitor approved for the treatment of idiopathic pulmonary fibrosis, has anti-fibrotic, anti-inflammatory, and anti-angiogenic activity. We explored the impact of nintedanib on microvascular architecture in a pulmonary fibrosis model. Lung fibrosis was induced in C57Bl/6 mice by intratracheal bleomycin (0.5 mg/kg). Nintedanib was started after the onset of lung pathology (50 mg/kg twice daily, orally). Micro-computed tomography was performed via volumetric assessment. Static lung compliance and forced vital capacity were determined by invasive measurements. Mice were subjected to bronchoalveolar lavage and histologic analyses, or perfused with a casting resin. Microvascular corrosion casts were imaged by scanning electron microscopy and synchrotron radiation tomographic microscopy, and quantified morphometrically. Bleomycin administration resulted in a significant increase in higher-density areas in the lungs detected by micro-computed tomography, which was significantly attenuated by nintedanib. Nintedanib significantly reduced lung fibrosis and vascular proliferation, normalized the distorted microvascular architecture, and was associated with a trend toward improvement in lung function and inflammation. Nintedanib resulted in a prominent improvement in pulmonary microvascular architecture, which outperformed the effect of nintedanib on lung function and inflammation. These findings uncover a potential new mode of action of nintedanib that may contribute to its efficacy in idiopathic pulmonary fibrosis.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Johann-Joachim-Becher-Weg 13, 55128, Mainz, Germany.
| | - Yong Ook Kim
- Institute of Translational Immunology and Research Center for Immune Therapy (FZI), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Willi L Wagner
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Johann-Joachim-Becher-Weg 13, 55128, Mainz, Germany
| | - Detlef Schuppan
- Institute of Translational Immunology and Research Center for Immune Therapy (FZI), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.,Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Cristian D Valenzuela
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Steven J Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Sebastian Kreuz
- Immunology and Respiratory Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Detlef Stiller
- Immunology and Respiratory Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Lutz Wollin
- Immunology and Respiratory Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Johann-Joachim-Becher-Weg 13, 55128, Mainz, Germany
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Forner K, Roos C, Dahlgren D, Kesisoglou F, Konerding MA, Mazur J, Lennernäs H, Langguth P. Optimization of the Ussing chamber setup with excised rat intestinal segments for dissolution/permeation experiments of poorly soluble drugs. Drug Dev Ind Pharm 2016; 43:338-346. [PMID: 27762631 DOI: 10.1080/03639045.2016.1251449] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
CONTEXT Prediction of the in vivo absorption of poorly soluble drugs may require simultaneous dissolution/permeation experiments. In vivo predictive media have been modified for permeation experiments with Caco-2 cells, but not for excised rat intestinal segments. OBJECTIVE The present study aimed at improving the setup of dissolution/permeation experiments with excised rat intestinal segments by assessing suitable donor and receiver media. METHODS The regional compatibility of rat intestine in Ussing chambers with modified Fasted and Fed State Simulated Intestinal Fluids (Fa/FeSSIFmod) as donor media was evaluated via several parameters that reflect the viability of the excised intestinal segments. Receiver media that establish sink conditions were investigated for their foaming potential and toxicity. Dissolution/permeation experiments with the optimized conditions were then tested for two particle sizes of the BCS class II drug aprepitant. RESULTS Fa/FeSSIFmod were toxic for excised rat ileal sheets but not duodenal sheets, the compatibility with jejunal segments depended on the bile salt concentration. A non-foaming receiver medium containing bovine serum albumin (BSA) and Antifoam B was nontoxic. With these conditions, the permeation of nanosized aprepitant was higher than of the unmilled drug formulations. DISCUSSION The compatibility of Fa/FeSSIFmod depends on the excised intestinal region. The chosen conditions enable dissolution/permeation experiments with excised rat duodenal segments. The experiments correctly predicted the superior permeation of nanosized over unmilled aprepitant that is observed in vivo. CONCLUSION The optimized setup uses FaSSIFmod as donor medium, excised rat duodenal sheets as permeation membrane and a receiver medium containing BSA and Antifoam B.
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Affiliation(s)
- Kristin Forner
- a Department of Pharmaceutical Technology and Biopharmaceutics , Johannes Gutenberg University , Mainz , Germany
| | - Carl Roos
- b Department of Pharmacy , Uppsala University , Uppsala , Sweden
| | - David Dahlgren
- b Department of Pharmacy , Uppsala University , Uppsala , Sweden
| | - Filippos Kesisoglou
- c Department of Biopharmaceutics, Pharmaceutical Sciences and Clinical Supply , Merck & Co. Inc ., Kenilworth , NJ , USA
| | - Moritz A Konerding
- d Institute of Clinical and Functional Anatomy , University Medical Center Johannes Gutenberg University , Mainz , Germany
| | - Johanna Mazur
- e Institute of Medical Biostatistics, Epidemiology and Informatics , University Medical Center Johannes Gutenberg University , Mainz , Germany
| | - Hans Lennernäs
- b Department of Pharmacy , Uppsala University , Uppsala , Sweden
| | - Peter Langguth
- a Department of Pharmaceutical Technology and Biopharmaceutics , Johannes Gutenberg University , Mainz , Germany
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Conrad J, Ayyad A, Wüster C, Omran W, Weber MM, Konerding MA, Müller-Forell W, Giese A, Oertel J. Binostril versus mononostril approaches in endoscopic transsphenoidal pituitary surgery: clinical evaluation and cadaver study. J Neurosurg 2016; 125:334-45. [PMID: 26722858 DOI: 10.3171/2015.6.jns142637] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Over the past 2 decades, endoscopy has become an integral part of the surgical repertoire for skull base procedures. The present clinical evaluation and cadaver study compare binostril and mononostril endoscopic transnasal approaches and the surgical techniques involved. METHODS Forty patients with pituitary adenomas were treated with either binostril or mononostril endoscopic surgery. Neurosurgical, endocrinological, ophthalmological, and neuroradiological examinations were performed. Ten cadaver specimens were prepared, and surgical aspects of the preparation and neuroradiological examination were documented. RESULTS In the clinical evaluation, 0° optics were optimal in the nasal and sphenoidal phase of surgery for both techniques. For detection of tumor remnants, 30° optics were superior. The binostril approach was significantly more time consuming than the mononostril technique. The nasal retractor limited maneuverability of instruments during mononostril approaches in 5 of 20 patients. Endocrinological pituitary function, control of excessive hormone secretion, ophthalmological outcome, residual tumor, and rates of adverse events, such as CSF leaks and diabetes insipidus, were similar in both groups. In the cadaver study, there was no significant difference in the time required for dissection via the binostril or mononostril technique. The panoramic view was superior in the binostril group; this was due to the possibility of wider opening of the sella in the craniocaudal and horizontal directions, but the need for removal of more of the nasal septum was disadvantageous. CONCLUSIONS Because of maneuverability of instruments and a wider view in the sphenoid sinus, the binostril technique is superior for resection of large tumors with parasellar and suprasellar expansion and tumors requiring extended approaches. The mononostril technique is preferable for tumors with limited extension in the intra- and suprasellar area.
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Affiliation(s)
| | - Ali Ayyad
- Neurochirurgische Klinik und Poliklinik
| | | | | | | | - Moritz A Konerding
- Institut für Anatomie und Zellbiologie, Fachbereich Medizin, Johannes Gutenberg-Universität Mainz
| | | | - Alf Giese
- Neurochirurgische Klinik und Poliklinik
| | - Joachim Oertel
- Klinik für Neurochirurgie, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany
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Wagner W, Bennett RD, Ackermann M, Ysasi A, Belle J, Valenzuela C, Pabst A, Tsuda A, Konerding MA, Mentzer SJ. Elastin Cables Define the Axial Connective Tissue System in the Murine Lung. Anat Rec (Hoboken) 2015; 298:1960-8. [PMID: 26285785 PMCID: PMC4677820 DOI: 10.1002/ar.23259] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 05/19/2015] [Accepted: 06/25/2015] [Indexed: 11/09/2022]
Abstract
The axial connective tissue system is a fiber continuum of the lung that maintains alveolar surface area during changes in lung volume. Although the molecular anatomy of the axial system remains undefined, the fiber continuum of the lung is central to contemporary models of lung micromechanics and alveolar regeneration. To provide a detailed molecular structure of the axial connective tissue system, we examined the extracellular matrix of murine lungs. The lungs were decellularized using a 24 hr detergent treatment protocol. Systematic evaluation of the decellularized lungs demonstrated no residual cellular debris; morphometry demonstrated a mean 39 ± 7% reduction in lung dimensions. Scanning electron microscopy (SEM) demonstrated an intact structural hierarchy within the decellularized lung. Light, fluorescence, and SEM of precision-cut lung slices demonstrated that alveolar duct structure was defined by a cable line element encased in basement membrane. The cable line element arose in the distal airways, passed through septal tips and inserted into neighboring blood vessels and visceral pleura. The ropelike appearance, collagenase resistance and anti-elastin immunostaining indicated that the cable was an elastin macromolecule. Our results indicate that the helical line element of the axial connective tissue system is composed of an elastin cable that not only defines the structure of the alveolar duct, but also integrates the axial connective tissue system into visceral pleura and peripheral blood vessels.
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Affiliation(s)
- Willi Wagner
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Robert D. Bennett
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Maximlian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Alexandra Ysasi
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Janeil Belle
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Cristian Valenzuela
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Andreas Pabst
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
| | - Moritz A. Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Steven J. Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
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Kelly P, McClean PL, Ackermann M, Konerding MA, Hölscher C, Mitchell CA. Restoration of cerebral and systemic microvascular architecture in APP/PS1 transgenic mice following treatment with Liraglutide™. Microcirculation 2015; 22:133-45. [PMID: 25556713 DOI: 10.1111/micc.12186] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 12/23/2014] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Cerebral microvascular impairments occurring in AD may reduce Aβ peptide clearance and impact upon circulatory ultrastructure and function. We hypothesized that microvascular pathologies occur in organs responsible for systemic Aβ peptide clearance in a model of AD and that Liraglutide (Victoza(®)) improves vessel architecture. METHODS Seven-month-old APP/PS1 and age-matched wild-type mice received once-daily intraperitoneal injections of either Liraglutide or saline (n = 4 per group) for eight weeks. Casts of cerebral, splenic, hepatic, and renal microanatomy were analyzed using SEM. RESULTS Casts from wild-type mice showed regularly spaced microvasculature with smooth lumenal profiles, whereas APP/PS1 mice revealed evidence of microangiopathies including cerebral microanuerysms, intracerebral microvascular leakage, extravasation from renal glomerular microvessels, and significant reductions in both splenic sinus density (p = 0.0286) and intussusceptive microvascular pillars (p = 0.0412). Quantification of hepatic vascular ultrastructure in APP/PS1 mice revealed that vessel parameters (width, length, branching points, intussusceptive pillars and microaneurysms) were not significantly different from wild-type mice. Systemic administration of Liraglutide reduced the incidence of cerebral microanuerysms and leakage, restored renal microvascular architecture and significantly increased both splenic venous sinus number (p = 0.0286) and intussusceptive pillar formation (p = 0.0129). CONCLUSION Liraglutide restores cerebral, splenic, and renal architecture in APP/PS1 mice.
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Affiliation(s)
- Patricia Kelly
- School of Biomedical Sciences, University of Ulster, Coleraine, UK
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Ackermann M, Wettstein R, Senaldi C, Kalbermatten DF, Konerding MA, Raffoul W, Erba P. Impact of platelet rich plasma and adipose stem cells on lymphangiogenesis in a murine tail lymphedema model. Microvasc Res 2015; 102:78-85. [PMID: 26365474 DOI: 10.1016/j.mvr.2015.09.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 09/06/2015] [Accepted: 09/06/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUND Lymphedema is an underdiagnosed pathology which in industrialized countries mainly affects cancer patients that underwent lymph node dissection and/or radiation. Currently no effective therapy is available so that patients' life quality is compromised by swellings of the concerned body region. This unfortunate condition is associated with body imbalance and subsequent osteochondral deformations and impaired function as well as with an increased risk of potentially life threatening soft tissue infections. METHODS The effects of PRP and ASC on angiogenesis (anti-CD31 staining), microcirculation (Laser Doppler Imaging), lymphangiogenesis (anti-LYVE1 staining), microvascular architecture (corrosion casting) and wound healing (digital planimetry) are studied in a murine tail lymphedema model. RESULTS Wounds treated by PRP and ASC healed faster and showed a significantly increased epithelialization mainly from the proximal wound margin. The application of PRP induced a significantly increased lymphangiogenesis while the application of ASC did not induce any significant change in this regard. CONCLUSIONS PRP and ASC affect lymphangiogenesis and lymphedema development and might represent a promising approach to improve regeneration of lymphatic vessels, restore disrupted lymphatic circulation and treat or prevent lymphedema alone or in combination with currently available lymphedema therapies.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Reto Wettstein
- Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Lausanne (CHUV), Lausanne, Switzerland; Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Basel, Basel, Switzerland
| | - Christopher Senaldi
- Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Lausanne (CHUV), Lausanne, Switzerland
| | - Daniel F Kalbermatten
- Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Lausanne (CHUV), Lausanne, Switzerland; Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Basel, Basel, Switzerland
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Wassim Raffoul
- Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Lausanne (CHUV), Lausanne, Switzerland
| | - Paolo Erba
- Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital of Lausanne (CHUV), Lausanne, Switzerland; Department of ORL, Head and Neck Surgery, University Hospital of Bern, Bern, Switzerland.
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Giacomini A, Ackermann M, Belleri M, Coltrini D, Nico B, Ribatti D, Konerding MA, Presta M, Righi M. Brain angioarchitecture and intussusceptive microvascular growth in a murine model of Krabbe disease. Angiogenesis 2015; 18:499-510. [DOI: 10.1007/s10456-015-9481-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 08/13/2015] [Indexed: 10/23/2022]
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Reineke DC, Müller-Schweinitzer E, Winkler B, Kunz D, Konerding MA, Grussenmeyer T, Carrel TP, Eckstein FS, Grapow MTR. Rapamycin impairs endothelial cell function in human internal thoracic arteries. Eur J Med Res 2015; 20:59. [PMID: 26104664 PMCID: PMC4502526 DOI: 10.1186/s40001-015-0150-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 06/17/2015] [Indexed: 12/17/2022] Open
Abstract
Background Definitive fate of the coronary endothelium after implantation of a drug-eluting stent remains unclear, but evidence has accumulated that treatment with rapamycin-eluting stents impairs endothelial function in human coronary arteries. The aim of our study was to demonstrate this phenomenon on functional, morphological and biochemical level in human internal thoracic arteries (ITA) serving as coronary artery model. Methods After exposure to rapamycin for 20 h, functional activity of ITA rings was investigated using the organ bath technique. Morphological analysis was performed by scanning electron microscopy and evaluated by two independent observers in blinded fashion. For measurement of endothelial nitric oxide synthase (eNOS) release, mammalian target of rapamycin (mTOR) and protein kinase B (PKB) (Akt) activation, Western blotting on human mammary epithelial cells-1 and on ITA homogenates was performed. Results Comparison of the acetylcholine-induced relaxation revealed a significant concentration-dependent decrease to 66 ± 7 % and 36 ± 7 % (mean ± SEM) after 20-h incubation with 1 and 10 μM rapamycin. Electron microscopic evaluation of the endothelial layer showed no differences between controls and samples exposed to 10 μM rapamycin. Western blots after 20-h incubation with rapamycin (10 nM–1 μM) revealed a significant and concentration-dependent reduction of p (Ser 1177)-eNOS (down to 38 ± 8 %) in human mammary epithelial cells (Hmec)-1. Furthermore, 1 μM rapamycin significantly reduced activation of p (Ser2481)-mTOR (58 ± 11 %), p (Ser2481)-mTOR (23 ± 4 %) and p (Ser473)-Akt (38 ± 6 %) in ITA homogenates leaving Akt protein levels unchanged. Conclusions The present data suggests that 20-h exposure of ITA rings to rapamycin reduces endothelium-mediated relaxation through down-regulation of Akt-phosphorylation via the mTOR signalling axis within the ITA tissue without injuring the endothelial cell layer.
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Affiliation(s)
- David C Reineke
- Department of Cardiovascular Surgery, University Hospital Berne, Bern, CH-3010, Switzerland
| | - Else Müller-Schweinitzer
- Department of Cardiac Surgery, University Hospital Basel, Spitalstrasse 21, Basel, CH-4031, Switzerland.,Department of Biomedicine, University Basel, Basel, CH-4031, Switzerland
| | - Bernhard Winkler
- Department of Cardiovascular Surgery, University Hospital Berne, Bern, CH-3010, Switzerland.,Department of Biomedicine, University Basel, Basel, CH-4031, Switzerland
| | - Donatina Kunz
- Department of Cardiac Surgery, University Hospital Basel, Spitalstrasse 21, Basel, CH-4031, Switzerland.,Department of Biomedicine, University Basel, Basel, CH-4031, Switzerland
| | - Moritz A Konerding
- Department of Anatomy, Johannes Gutenberg-University, Mainz, 55099, Germany
| | - Thomas Grussenmeyer
- Department of Cardiac Surgery, University Hospital Basel, Spitalstrasse 21, Basel, CH-4031, Switzerland.,Department of Biomedicine, University Basel, Basel, CH-4031, Switzerland
| | - Thierry P Carrel
- Department of Cardiovascular Surgery, University Hospital Berne, Bern, CH-3010, Switzerland
| | - Friedrich S Eckstein
- Department of Cardiac Surgery, University Hospital Basel, Spitalstrasse 21, Basel, CH-4031, Switzerland.,Department of Biomedicine, University Basel, Basel, CH-4031, Switzerland
| | - Martin T R Grapow
- Department of Cardiac Surgery, University Hospital Basel, Spitalstrasse 21, Basel, CH-4031, Switzerland. .,Department of Biomedicine, University Basel, Basel, CH-4031, Switzerland.
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Ysasi AB, Wagner WL, Bennett RD, Ackermann M, Valenzuela CD, Belle J, Tsuda A, Konerding MA, Mentzer SJ. Remodeling of alveolar septa after murine pneumonectomy. Am J Physiol Lung Cell Mol Physiol 2015; 308:L1237-44. [PMID: 26078396 PMCID: PMC4587600 DOI: 10.1152/ajplung.00042.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 04/09/2015] [Indexed: 11/22/2022] Open
Abstract
In most mammals, removing one lung (pneumonectomy) results in the compensatory growth of the remaining lung. In mice, stereological observations have demonstrated an increase in the number of mature alveoli; however, anatomic evidence of the early phases of alveolar growth has remained elusive. To identify changes in the lung microstructure associated with neoalveolarization, we used tissue histology, electron microscopy, and synchrotron imaging to examine the configuration of the alveolar duct after murine pneumonectomy. Systematic histological examination of the cardiac lobe demonstrated no change in the relative frequency of dihedral angle components (Ends, Bends, and Junctions) (P > 0.05), but a significant decrease in the length of a subset of septal ends ("E"). Septal retraction, observed in 20-30% of the alveolar ducts, was maximal on day 3 after pneumonectomy (P < 0.01) and returned to baseline levels within 3 wk. Consistent with septal retraction, the postpneumonectomy alveolar duct diameter ratio (Dout:Din) was significantly lower 3 days after pneumonectomy compared to all controls except for the detergent-treated lung (P < 0.001). To identify clumped capillaries predicted by septal retraction, vascular casting, analyzed by both scanning electron microscopy and synchrotron imaging, demonstrated matted capillaries that were most prominent 3 days after pneumonectomy. Numerical simulations suggested that septal retraction could reflect increased surface tension within the alveolar duct, resulting in a new equilibrium at a higher total energy and lower surface area. The spatial and temporal association of these microstructural changes with postpneumonectomy lung growth suggests that these changes represent an early phase of alveolar duct remodeling.
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Affiliation(s)
- Alexandra B Ysasi
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Willi L Wagner
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany; and
| | - Robert D Bennett
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany; and
| | - Cristian D Valenzuela
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Janeil Belle
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, Massachusetts
| | - Moritz A Konerding
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Steven J Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts;
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12
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Abstract
Microvascularity and angiogenesis play a pivotal role during normal growth and in a variety of pathological conditions such as inflammation, tumor growth, macular degeneration, and tissue regeneration. Vascular corrosion casting has been established as a method to analyze and evaluate two- and three-dimensionally the morphology and architecture of blood vessels of organs and tissues, such as tumors, brains, embryos, or the chorioallantoic membrane. Microvascular casts may be further dissected for visualizing and quantifying vascular morphology using scanning electron microscopy (SEM), micro computed tomographic (μCT) imaging, or synchrotron radiation-based micro computed tomographic (SRμCT) imaging.
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Affiliation(s)
- Maximilian Ackermann
- Department of Oral and Maxillofacial Surgery, Institute of Functional and Clinical Anatomy, University Medical Center Mainz, Mainz, Germany
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13
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Bennett RD, Ysasi AB, Belle JM, Wagner WL, Konerding MA, Blainey PC, Pyne S, Mentzer SJ. Laser microdissection of the alveolar duct enables single-cell genomic analysis. Front Oncol 2014; 4:260. [PMID: 25309876 PMCID: PMC4173809 DOI: 10.3389/fonc.2014.00260] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Accepted: 09/06/2014] [Indexed: 01/12/2023] Open
Abstract
Complex tissues such as the lung are composed of structural hierarchies such as alveoli, alveolar ducts, and lobules. Some structural units, such as the alveolar duct, appear to participate in tissue repair as well as the development of bronchioalveolar carcinoma. Here, we demonstrate an approach to conduct laser microdissection of the lung alveolar duct for single-cell PCR analysis. Our approach involved three steps. (1) The initial preparation used mechanical sectioning of the lung tissue with sufficient thickness to encompass the structure of interest. In the case of the alveolar duct, the precision-cut lung slices were 200 μm thick; the slices were processed using near-physiologic conditions to preserve the state of viable cells. (2) The lung slices were examined by transmission light microscopy to target the alveolar duct. The air-filled lung was sufficiently accessible by light microscopy that counterstains or fluorescent labels were unnecessary to identify the alveolar duct. (3) The enzymatic and microfluidic isolation of single cells allowed for the harvest of as few as several thousand cells for PCR analysis. Microfluidics based arrays were used to measure the expression of selected marker genes in individual cells to characterize different cell populations. Preliminary work suggests the unique value of this approach to understand the intra- and intercellular interactions within the regenerating alveolar duct.
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Affiliation(s)
- Robert D Bennett
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School , Boston, MA , USA
| | - Alexandra B Ysasi
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School , Boston, MA , USA
| | - Janeil M Belle
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School , Boston, MA , USA
| | - Willi L Wagner
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University , Mainz , Germany
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University , Mainz , Germany
| | - Paul C Blainey
- Broad Institute of Massachusetts Institute of Technology, Harvard University , Cambridge, MA , USA
| | - Saumyadipta Pyne
- CR Rao Advanced Institute of Mathematics, Statistics and Computer Science , Hyderabad , India
| | - Steven J Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School , Boston, MA , USA
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14
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Pabst AM, Wagner W, Kasaj A, Gebhardt S, Ackermann M, Astolfo A, Marone F, Haberthür D, Enzmann F, Konerding MA. Synchrotron-based X-ray tomographic microscopy for visualization of three-dimensional collagen matrices. Clin Oral Investig 2014; 19:561-4. [PMID: 25209594 DOI: 10.1007/s00784-014-1312-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 08/26/2014] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Three-dimensional collagen matrices (3D-CMs) may be visualized by cumbersome reconstructions of serial sections. We report here on the method of synchrotron-based X-ray tomographic microscopy (SRXTM) to image 3D-CMs in native tissue probes. MATERIAL AND METHODS SRXTM of 3D-CMs (mucoderm®, mucograft®) was performed at the TOMCAT beamline of the Swiss Light Source (SLS) at the Paul Scherrer Institute (Villigen, Switzerland). RESULTS SRXTM combines the advantages of high-resolution scanning electron microscopy (SEM) imaging with the low-resolution reconstructions of micro-CT (μCT) imaging. It may be used to non-destructively visualize and analyze structures within the 3D-CMs without the need of serial sectioning and reconstruction. CONCLUSION High-resolution SRXTM is a useful tool in analyzing the topology and morphometry of structures in 3D-CMs. The outcome justifies the efforts in sophisticated data processing. CLINICAL RELEVANCE SRXTM may help to understand the clinical characteristics of 3D-CMs in more detail.
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Affiliation(s)
- A M Pabst
- Institute of Functional and Clinical Anatomy, University Medical Center Mainz, Becherweg 13, 55099, Mainz, Germany
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15
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Belle J, Ysasi A, Bennett RD, Filipovic N, Nejad MI, Trumper DL, Ackermann M, Wagner W, Tsuda A, Konerding MA, Mentzer SJ. Stretch-induced intussuceptive and sprouting angiogenesis in the chick chorioallantoic membrane. Microvasc Res 2014; 95:60-7. [PMID: 24984292 PMCID: PMC4188740 DOI: 10.1016/j.mvr.2014.06.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 05/30/2014] [Accepted: 06/21/2014] [Indexed: 01/10/2023]
Abstract
Vascular systems grow and remodel in response to not only metabolic needs, but also mechanical influences as well. Here, we investigated the influence of tissue-level mechanical forces on the patterning and structure of the chick chorioallantoic membrane (CAM) microcirculation. A dipole stretch field was applied to the CAM using custom computer-controlled servomotors. The topography of the stretch field was mapped using finite element models. After 3days of stretch, Sholl analysis of the CAM demonstrated a 7-fold increase in conducting vessel intersections within the stretch field (p<0.01). The morphometric analysis of intravital microscopy and scanning electron microscopy (SEM) images demonstrated that the increase vessel density was a result of an increase in interbranch distance (p<0.01) and a decrease in bifurcation angles (p<0.01); there was no significant increase in conducting vessel number (p>0.05). In contrast, corrosion casting and SEM of the stretch field capillary meshwork demonstrated intense sprouting and intussusceptive angiogenesis. Both planar surface area (p<0.05) and pillar density (p<0.01) were significantly increased relative to control regions of the CAM. We conclude that a uniaxial stretch field stimulates the axial growth and realignment of conducting vessels as well as intussusceptive and sprouting angiogenesis within the gas exchange capillaries of the ex ovo CAM.
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Affiliation(s)
- Janeil Belle
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Alexandra Ysasi
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Robert D Bennett
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Nenad Filipovic
- Faculty of Mechanical Engineering, University of Kragujevac, Serbia
| | - Mohammad Imani Nejad
- Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - David L Trumper
- Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Willi Wagner
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA, USA
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Steven J Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA.
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16
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Belle JM, Lee GS, Ysasi AB, Bennett RD, Ackermann M, Wagner WL, Konerding MA, Tsuda A, Mentzer SJ. Laser-Targeted Occlusion Of Microvessels Induces Compensatory Intussusceptive Angiogenesis. J Am Coll Surg 2014. [DOI: 10.1016/j.jamcollsurg.2014.07.382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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17
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Belle JM, Ysasi AB, Bennett RD, Ackermann M, Wagner WL, Konerding MA, Tsuda A, Mentzer SJ. Micromechanical Forces Trigger Tissue-Level Sprouting and Intussusceptive Angiogenesis. J Am Coll Surg 2014. [DOI: 10.1016/j.jamcollsurg.2014.07.387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Bennett RD, Ysasi AB, Belle JM, Wagner WL, Ackermann M, Konerding MA, Tsuda A, Mentzer SJ. Glycoconjugate Expression in the Tissue-Engineered Lung Scaffold after Murine Pneumonectomy. J Am Coll Surg 2014. [DOI: 10.1016/j.jamcollsurg.2014.07.077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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19
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Wegmann K, Burkhart KJ, Zimmermann J, Dargel J, Nijs S, Konerding MA, Müller LP. The interference of distal humeral plating with the medial and lateral collateral ligaments of the elbow. Arch Orthop Trauma Surg 2014; 134:501-7. [PMID: 24531976 DOI: 10.1007/s00402-014-1952-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Indexed: 12/01/2022]
Abstract
INTRODUCTION The aim of the present study was to determine the anatomical relationship and evaluate the potential interference of today's common distal humerus plates with the medial and lateral collateral ligaments of the elbow. MATERIALS AND METHODS The elbow joints of 23 embalmed upper extremities were dissected. Three different brands of distal humerus double-plating systems were applied in a standardized fashion. We used a caliper to measure the amount of absolute overlap of the plates on the corresponding collateral ligaments. RESULTS The data show contact and overlap with the medial and lateral collateral ligaments in all tested medial and lateral plates. The posterolateral and posteromedial plates showed no contact with the ligaments, yet they did contact the posterior joint capsules. The medial plates showed less contact/overlap when compared with the lateral and extended medial plates. CONCLUSION Based on the present data, we conclude that distal humerus plating using the perpendicular technique with standard-sized medial plates shows the least amount of overlap over the medial and lateral collateral ligaments. The extent of the overlap of the ligaments by the humeral plates is clearly shown in the present study.
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Affiliation(s)
- Kilian Wegmann
- Center for Orthopaedic and Trauma Surgery, University Medical Center, Cologne, Germany,
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20
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Ackermann M, Pabst AM, Houdek JP, Ziebart T, Konerding MA. Priming with proangiogenic growth factors and endothelial progenitor cells improves revascularization in linear diabetic wounds. Int J Mol Med 2014; 33:833-9. [PMID: 24452195 PMCID: PMC3976131 DOI: 10.3892/ijmm.2014.1630] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 01/15/2014] [Indexed: 12/26/2022] Open
Abstract
In the present study, we investigated whether proangiogenic growth factors and endothelial progenitor cells (EPCs) induce favourable effects on cutaneous incisional wound healing in diabetic mice. The proangiogenic effects of human EPCs were initially analyzed using a HUVEC in vitro angiogenesis assay and an in vivo Matrigel assay in nude mice (n=12). For the diabetic wound model, 48 Balb/c mice with streptozotocin (STZ)-induced diabetes were divided randomly into 4 groups (12 mice in each group). Subsequently, 3, 5 and 7 days before a 15-mm full-thickness incisional skin wound was set, group 1 was pre-treated subcutaneously with a mixture of vascular endothelial growth factor (VEGF)/basic fibroblast growth factor (bFGF)/platelet-derived growth factor (PDGF) (3.5 µg of each), group 2 with 3.5 µg PDGF and group 3 with an aliquot of two million EPCs, whereas the control animals (group 4) were pre-treated with 0.2 ml saline solution. The wounds were assessed daily and the repaired tissues were harvested 7 days after complete wound closure. The angiogenesis assay demonstrated significantly increased sprout densities, areas and lengths in the EPC-treated group (all p<0.01). In the Matrigel assay, significantly increased microvessel densities, areas and sizes (all p<0.001) were also detected in the EPC-treated group. In the STZ-induced model of diabetes, the animals pre-treated with a combination of proangiogenic factors and EPCs showed in general, a more rapid wound closure. Vessel densities were >2-fold higher in the mice treated with a combination of proangiogenic factors and EPCs (p<0.05) and tensile strengths were higher in the groups treated with proangiogenic growth factors compared to the controls (p<0.05). These results suggest a beneficial effect of pre-treatment with proangiogenic growth factors and EPCs in incisional wound healing.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center Mainz, D-55131 Mainz, Germany
| | - Andreas M Pabst
- Institute of Functional and Clinical Anatomy, University Medical Center Mainz, D-55131 Mainz, Germany
| | - Jan P Houdek
- Institute of Functional and Clinical Anatomy, University Medical Center Mainz, D-55131 Mainz, Germany
| | - Thomas Ziebart
- Department of Oral and Maxillofacial Surgery, University Medical Center Mainz, D-55131 Mainz, Germany
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center Mainz, D-55131 Mainz, Germany
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21
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Ackermann M, Houdek JP, Gibney BC, Ysasi A, Wagner W, Belle J, Schittny JC, Enzmann F, Tsuda A, Mentzer SJ, Konerding MA. Sprouting and intussusceptive angiogenesis in postpneumonectomy lung growth: mechanisms of alveolar neovascularization. Angiogenesis 2013; 17:541-51. [PMID: 24150281 PMCID: PMC4061467 DOI: 10.1007/s10456-013-9399-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 10/07/2013] [Indexed: 11/30/2022]
Abstract
In most rodents and some other mammals, the removal of one lung results in compensatory growth associated with dramatic angiogenesis and complete restoration of lung capacity. One pivotal mechanism in neoalveolarization is neovascularization, because without angiogenesis new alveoli can not be formed. The aim of this study is to image and analyze three-dimensionally the different patterns of neovascularization seen following pneumonectomy in mice on a sub-micron-scale. C57/BL6 mice underwent a left-sided pneumonectomy. Lungs were harvested at various timepoints after pneumonectomy. Volume analysis by microCT revealed a striking increase of 143 percent in the cardiac lobe 14 days after pneumonectomy. Analysis of microvascular corrosion casting demonstrated spatially heterogenous vascular densitities which were in line with the perivascular and subpleural compensatory growth pattern observed in anti-PCNA-stained lung sections. Within these regions an expansion of the vascular plexus with increased pillar formations and sprouting angiogenesis, originating both from pre-existing bronchial and pulmonary vessels was observed. Also, type II pneumocytes and alveolar macrophages were seen to participate actively in alveolar neo-angiogenesis after pneumonectomy. 3D-visualizations obtained by high-resolution synchrotron radiation X-ray tomographic microscopy showed the appearance of double-layered vessels and bud-like alveolar baskets as have already been described in normal lung development. Scanning electron microscopy data of microvascular architecture also revealed a replication of perialveolar vessel networks through septum formation as already seen in developmental alveolarization. In addition, the appearance of pillar formations and duplications on alveolar entrance ring vessels in mature alveoli are indicative of vascular remodeling. These findings indicate that sprouting and intussusceptive angiogenesis are pivotal mechanisms in adult lung alveolarization after pneumonectomy. Various forms of developmental neoalveolarization may also be considered to contribute in compensatory lung regeneration.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University Mainz, 55128, Mainz, Germany
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22
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Ysasi AB, Belle JM, Gibney BC, Fedulov AV, Wagner W, AkiraTsuda, Konerding MA, Mentzer SJ. Effect of unilateral diaphragmatic paralysis on postpneumonectomy lung growth. Am J Physiol Lung Cell Mol Physiol 2013; 305:L439-45. [PMID: 23873841 PMCID: PMC3763038 DOI: 10.1152/ajplung.00134.2013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 07/15/2013] [Indexed: 11/22/2022] Open
Abstract
Respiratory muscle-associated stretch has been implicated in normal lung development (fetal breathing movements) and postpneumonectomy lung growth. To test the hypothesis that mechanical stretch from diaphragmatic contraction contributes to lung growth, we performed left phrenic nerve transections (PNT) in mice with and without ipsilateral pneumonectomy. PNT was demonstrated by asymmetric costal margin excursion and confirmed at autopsy. In mice with two lungs, PNT was associated with a decrease in ipsilateral lung volume (P<0.05) and lung weight (P<0.05). After pneumonectomy, PNT was not associated with a change in activity level, measureable hypoxemia, or altered minute ventilation; however, microCT scanning demonstrated altered displacement and underinflation of the cardiac lobe within the first week after pneumonectomy. Coincident with the altered structural realignment, lung impedance measurements, fitted to the constant-phase model, demonstrated elevated airway resistance (P<0.05), but normal peripheral tissue resistance (P>0.05). Most important, PNT appeared to abrogate compensatory lung growth after pneumonectomy; the weight of the lobes of the right lung was significantly less than pneumonectomy alone (P<0.001) and indistinguishable from nonsurgical controls (P>0.05). We conclude that the cyclic stretch associated with diaphragmatic muscle contraction is a controlling factor in postpneumonectomy compensatory lung growth.
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Affiliation(s)
- Alexandra B Ysasi
- Rm. 259, Brigham &Women's Hospital, 75 Francis St., Boston, MA 02115.
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23
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Filipovic N, Gibney BC, Kojic M, Nikolic D, Isailovic V, Ysasi A, Konerding MA, Mentzer SJ, Tsuda A. Mapping cyclic stretch in the postpneumonectomy murine lung. J Appl Physiol (1985) 2013; 115:1370-8. [PMID: 23990237 DOI: 10.1152/japplphysiol.00635.2013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In many mammalian species, the removal of one lung [pneumonectomy (PNX)] is associated with the compensatory growth of the remaining lung. To investigate the hypothesis that parenchymal deformation may trigger lung regeneration, we used respiratory-gated micro-computed tomography scanning to create three-dimensional finite-element geometric models of the murine cardiac lobe with cyclic breathing. Models were constructed of respiratory-gated micro-computed tomography scans pre-PNX and 24 h post-PNX. The computational models demonstrated that the maximum stretch ratio map was patchy and heterogeneous, particularly in subpleural, juxta-diaphragmatic, and cephalad regions of the lobe. In these parenchymal regions, the material line segments at peak inspiration were frequently two- to fourfold greater after PNX; some regions of the post-PNX cardiac lobe demonstrated parenchymal compression at peak inspiration. Similarly, analyses of parenchymal maximum shear strain demonstrated heterogeneous regions of mechanical stress with focal regions demonstrating a threefold increase in shear strain after PNX. Consistent with previously identified growth patterns, these subpleural regions of enhanced stretch and shear strain are compatible with a mechanical signal, likely involving cyclic parenchymal stretch, triggering lung growth.
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Affiliation(s)
- Nenad Filipovic
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
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24
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Ziebart T, Ziebart J, Gauss L, Pabst A, Ackermann M, Smeets R, Konerding MA, Walter C. Investigation of inhibitory effects on EPC-mediated neovascularization by different bisphosphonates for cancer therapy. Biomed Rep 2013; 1:719-722. [PMID: 24649016 DOI: 10.3892/br.2013.145] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 07/11/2012] [Indexed: 12/16/2022] Open
Abstract
Bisphosphonates (BPs) are potent drugs, used in metastatic cancer-like prostate or breast carcinoma. In recent studies, besides reduced bone remodeling, influences on angiogenesis and neovascularization were reported. Since BPs have the tendency to accumulate in the bones, the biological effect of various nitrogen- and non-nitrogen BPs on endothelial progenitor cells (EPCs) that originated from bone marrow and mobilized under physiological and pathophysiological conditions, such as tumor neovascularization, was investigated. EPCs subsequent to 72-h treatment with different concentrations of bisphosphonates comprised the non-nitrogen-containing BP clodronate and the nitrogen-containing BPs ibandronate, pamidronate and zoledronate. After incubation, biological activity was measured by using the migration boyden chamber assay and measurement of the colony-forming ability. Nitrogen-containing BPs inhibited the migration ability and differentiation of EPCs in a dose-dependent manner, as compared to the non-treated control groups. More specifically, the nitrogen-containing BP zoledronate significantly inhibited angiogenesis and neovascularization. Clodronate was less distinct on EPC function. To underline the importance of neovascularization in the context of tumor angiogenesis, EPC functions were significantly influenced in a dose-dependent manner by nitrogen-containing BPs. From these findings, we conclude that especially the nitrogen-containing BPs, such as zoledronate, are potential anticancer agents through the inhibition of neovascularization.
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Affiliation(s)
- Thomas Ziebart
- Department of Maxillofacial Surgery, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
| | - Johanna Ziebart
- Department of Maxillofacial Surgery, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz ; Department of Prosthodontics, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
| | - Leonie Gauss
- Department of Maxillofacial Surgery, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
| | - Andreas Pabst
- Department of Maxillofacial Surgery, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
| | - Ralf Smeets
- Department of Maxillofacial Surgery, University Medical Center of Hamburg-Eppendorf, Hamburg, Germany
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
| | - Christian Walter
- Department of Maxillofacial Surgery, University Medical Center of Johannes Gutenberg University Mainz, D-55131 Mainz
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25
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Chamoto K, Gibney BC, Lee GS, Ackermann M, Konerding MA, Tsuda A, Mentzer SJ. Migration of CD11b+ accessory cells during murine lung regeneration. Stem Cell Res 2013; 10:267-77. [PMID: 23376466 PMCID: PMC3622126 DOI: 10.1016/j.scr.2012.12.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 12/05/2012] [Accepted: 12/26/2012] [Indexed: 10/27/2022] Open
Abstract
In many mammalian species, the removal of one lung leads to growth of the remaining lung to near-baseline levels. In studying post-pneumonectomy mice, we used morphometric measures to demonstrate neoalveolarization within 21 days of pneumonectomy. Of note, the detailed histology during this period demonstrated no significant pulmonary inflammation. To identify occult blood-borne cells, we used a parabiotic model (wild-type/GFP) of post-pneumonectomy lung growth. Flow cytometry of post-pneumonectomy lung digests demonstrated a rapid increase in the number of cells expressing the hematopoietic membrane molecule CD11b; 64.5% of the entire GFP(+) population were CD11b(+). Fluorescence microscopy demonstrated that the CD11b(+) peripheral blood cells migrated into both the interstitial tissue and alveolar airspace compartments. Pneumonectomy in mice deficient in CD11b (CD18(-/-) mutants) demonstrated near-absent leukocyte migration into the airspace compartment (p<.001) and impaired lung growth as demonstrated by lung weight (p<.05) and lung volume (p<.05). Transcriptional activity of the partitioned CD11b(+) cells demonstrated significantly increased transcription of Angpt1, Il1b, and Mmp8, Mmp9, Ncam1, Sele, Sell, Selp in the alveolar airspace and Adamts2, Ecm1, Egf, Mmp7, Npr1, Tgfb2 in the interstitial tissue (>4-fold regulation; p<.05). These data suggest that blood-borne CD11b(+) cells represent a population of accessory cells contributing to post-pneumonectomy lung growth.
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Affiliation(s)
- Kenji Chamoto
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Barry C. Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Grace S. Lee
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Moritz A. Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
| | - Steven J. Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
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Konerding MA, Simpanen J, Ihlberg L, Aittomäki J, Werkkala K, Delventhal V, Ackermann M. Comparison of the novel Medtentia double helix mitral annuloplasty system with the Carpentier-Edwards Physio annuloplasty ring: morphological and functional long-term outcome in a mitral valve insufficiency sheep model. J Cardiothorac Surg 2013; 8:70. [PMID: 23566678 PMCID: PMC3681631 DOI: 10.1186/1749-8090-8-70] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 03/25/2013] [Indexed: 11/25/2022] Open
Abstract
Background The prevalence of mitral regurgitation in cardiac diseases requires annuloplasty systems that can be implanted without excessive patient burden. This study was designed to examine the morphological and functional outcome of a new double helix mitral annuloplasty ring in an ovine model in comparison to the classical Carpentier-Edwards (CE) annuloplasty ring as measured by reduction of mitral regurgitation and tissue integration. The Medtentia annuloplasty ring (MAR) is a helical device that is rotated into the annulus self-restoring the valve geometry, enabling a faster fixation without the need of elaborate repair of the valve geometry. The ventricular part of the helical ring encircles the valve chords. Methods Twenty adult sheep were overpaced until 2+ level mitral valve regurgitation was achieved. Seven animals per group received either the MAR or the CE ring. Implantation was performed on-pump in a beating heart through the left atrial appendix. The animals were sacrificed 3.6 ± 0.3 months after surgery following an echocardiography for assessing mitral regurgitation as primary endpoint. The annuloplasty rings with surrounding tissue were harvested for histological analyses as secondary endpoints. The remaining six sheep received the MAR system and were sampled seven, nine or 12 months after surgery. Results Implantation time (p < 0.01) and perfusion time (p < 0.001) as clinical secondary endpoints were significantly shorter in the MAR group. Echocardiography follow-ups showed sufficient valve function repair in nearly all animals with a normalization of the ventricle diameters in both groups (group difference: p = 0.147). The weights of the hearts did not differ significantly. Histology revealed adequately covered atrial annuloplasty rings with functional endothelium and lack of excessive granulation tissue or fibrosis in all specimens. The ventricular projections of the MAR systems encircling the chordae tendineae were not completely covered with neointimal tissue, although in no case were microthrombi detected and no thromboembolic events were recorded. Conclusions The new MAR system is an easy to use annuloplasty system with a functional outcome comparable to that of the well–proven CE ring. Mitral valve regurgitation is effectively stopped both by restricting the pathological expansion of the annulus and by gathering the chords without thrombus formation.
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Chamoto K, Gibney BC, Ackermann M, Lee GS, Konerding MA, Tsuda A, Mentzer SJ. Alveolar epithelial dynamics in postpneumonectomy lung growth. Anat Rec (Hoboken) 2013; 296:495-503. [PMID: 23408540 PMCID: PMC3576046 DOI: 10.1002/ar.22659] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/14/2012] [Accepted: 07/24/2012] [Indexed: 11/07/2022]
Abstract
The intimate anatomic and functional relationship between epithelial cells and endothelial cells within the alveolus suggests the likelihood of a coordinated response during postpneumonectomy lung growth. To define the population dynamics and potential contribution of alveolar epithelial cells to alveolar angiogenesis, we studied alveolar Type II and I cells during the 21 days after pneumonectomy. Alveolar Type II cells were defined and isolated by flow cytometry using a CD45(-) , MHC class II(+) , phosphine(+) phenotype. These phenotypically defined alveolar Type II cells demonstrated an increase in cell number after pneumonectomy; the increase in cell number preceded the increase in Type I (T1α(+) ) cells. Using a parabiotic wild type/GFP pneumonectomy model, <3% of the Type II cells and 1% of the Type I cells were positive for GFP-a finding consistent with the absence of a blood-borne contribution to alveolar epithelial cells. The CD45(-) , MHC class II(+) , phosphine(+) Type II cells demonstrated the active transcription of angiogenesis-related genes both before and after pneumonectomy. When the Type II cells on Day 7 after pneumonectomy were compared to nonsurgical controls, 10 genes demonstrated significantly increased expression (P<0.05). In contrast to the normal adult Type II cells, there was notable expression of inflammation-associated genes (Ccl2, Cxcl2, Ifng) as well as genes associated with epithelial growth (Ereg, Lep). Together, the data suggest an active contribution of local alveolar Type II cells to alveolar growth.
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Affiliation(s)
- Kenji Chamoto
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Barry C. Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Grace S. Lee
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Moritz A. Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
| | - Steven J. Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
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Ackermann M, Tsuda A, Secomb TW, Mentzer SJ, Konerding MA. Intussusceptive remodeling of vascular branch angles in chemically-induced murine colitis. Microvasc Res 2013; 87:75-82. [PMID: 23485588 DOI: 10.1016/j.mvr.2013.02.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 01/14/2013] [Accepted: 02/14/2013] [Indexed: 01/17/2023]
Abstract
Intussusceptive angiogenesis is a developmental process linked to both blood vessel replication and remodeling in development. To investigate the prediction that the process of intussusceptive angiogenesis is associated with vessel angle remodeling in adult mice, we systematically evaluated corrosion casts of the mucosal plexus in mice with trinitrobenzesulfonic acid (TNBS)-induced and dextran sodium sulfate (DSS)-induced colitis. The mice demonstrated a significant decrease in vessel angles in both TNBS-induced and DSS-induced colitis within 4 weeks of the onset of colitis (p<.001). Corrosion casts 28-30 days after DSS treatment were studied for a variety of detailed morphometric changes. The vessel diameter and interbranch distance were significantly increased in the descending colon (p<.05). Also consistent with vessel growth, intervascular distance was decreased in the descending colon (p<.05). In contrast, no statistically significant morphometric changes were noted in the ascending colon. The morphometry of the corrosion casts also demonstrated 1) a similar orientation of the remodeled angles within the XY coordinate plane of the mucosal plexus, and 2) alternating periodicity of remodeled and unremodeled vessel angles. We conclude that inflammation-associated intussusceptive angiogenesis in adult mice is associated with vessel angle remodeling. Further, the morphometry of the vessel angles suggests the influence of blood flow on the location and orientation of remodeled vessels.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
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Gibney BC, Houdek JP, Chamoto K, Lee GS, Ackermann M, Lin M, Collings-Simpson D, Konerding MA, Tsuda A, Mentzer SJ. Mechanostructural adaptations preceding postpneumonectomy lung growth. Exp Lung Res 2012; 38:396-405. [PMID: 22905715 PMCID: PMC4020359 DOI: 10.3109/01902148.2012.715364] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In many species, pneumonectomy results in compensatory growth in the remaining lung. Although the late mechanical consequences of murine pneumonectomy are known, little is known about the anatomic adaptations and respiratory mechanics during compensatory lung growth. To investigate the structural and mechanical changes during compensatory growth, mice were studied for 21 days after left pneumonectomy using microCT and respiratory system impedance (FlexiVent). Anatomic changes after left pneumonectomy included minimal mediastinal shift or chestwall remodeling, but significant displacement of the heart and cardiac lobe. Mean displacement of the cardiac lobe centroid was 5.2 ± 0.8 mm. Lung impedance measurements were used to investigate the associated changes in respiratory mechanics. Quasi-static pressure-volume loops demonstrated progressive increase in volumes with decreased distensibility. Measures of quasi-static compliance and elastance were increased at all time points postpneumonectomy (P < .01). Oscillatory mechanics demonstrated a significant change in tissue impedance on the third day after pneumonectomy. The input impedance on day 3 after pneumonectomy demonstrated a significant increase in tissue damping (5.8 versus 4.3 cm H(2)O/mL) and elastance (36.7 versus 26.6 cm H(2)O/mL) when compared to controls. At all points, hysteresivity was unchanged (0.17). We conclude that the timing and duration of the mechanical changes was consistent with a mechanical signal for compensatory growth.
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Affiliation(s)
- Barry C. Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard, Medical School, Boston MA
| | - Jan P. Houdek
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University Mainz, Germany
| | - Kenji Chamoto
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard, Medical School, Boston MA
| | - Grace S. Lee
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard, Medical School, Boston MA
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University Mainz, Germany
| | - Miao Lin
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard, Medical School, Boston MA
| | - Dinee Collings-Simpson
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard, Medical School, Boston MA
| | - Moritz A. Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg-University Mainz, Germany
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
| | - Steven J. Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard, Medical School, Boston MA
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Gibney BC, Park MA, Chamoto K, Ysasi A, Konerding MA, Tsuda A, Mentzer SJ. Detection of murine post-pneumonectomy lung regeneration by 18FDG PET imaging. EJNMMI Res 2012; 2:48. [PMID: 22999160 PMCID: PMC3504567 DOI: 10.1186/2191-219x-2-48] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 09/06/2012] [Indexed: 01/08/2023] Open
Abstract
UNLABELLED BACKGROUND An intriguing biologic process in most adult mammals is post-pneumonectomy lung regeneration, that is, the removal of one lung (pneumonectomy) results in the rapid compensatory growth of the remaining lung. The spatial dependence and metabolic activity of the rodent lung during compensatory lung regeneration is largely unknown. METHODS To determine if murine lung regeneration could be detected in vivo, we studied inbred mice 3, 7, 14, and 21 days after left pneumonectomy. The remaining lung was imaged using microCT as well as the glucose tracer 2-deoxy-2-[18 F]fluoro-d-glucose (18FDG) and positron-emission tomography (PET). Because of the compliance of the murine chest wall, reproducible imaging required orotracheal intubation and pressure-controlled ventilation during scanning. RESULTS After left pneumonectomy, the right lung progressively enlarged over the first 3 weeks. The cardiac lobe demonstrated the greatest percentage increase in size. Dry weights of the individual lobes largely mirrored the increase in lung volume. PET/CT imaging was used to identify enhanced metabolic activity within the individual lobes. In the cardiac lobe, 18FDG uptake was significantly increased in the day 14 cardiac lobe relative to preoperative values (p < .05). In contrast, the 18FDG uptake in the other three lobes was not statistically significant at any time point. CONCLUSIONS We conclude that the cardiac lobe is the dominant contributor to compensatory growth after murine pneumonectomy. Further, PET/CT scanning can detect both the volumetric increase and the metabolic changes associated with the regenerative growth in the murine cardiac lobe.
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Affiliation(s)
- Barry C Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mi-Ae Park
- Department of Radiology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Kenji Chamoto
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Alexandra Ysasi
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Moritz A Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz 55131, Germany
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA 02115, USA
| | - Steven J Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Brigham & Women's Hospital, 75 Francis Street, Room 259, Boston, MA 02115, USA
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Filipovic N, Gibney BC, Nikolic D, Konerding MA, Mentzer SJ, Tsuda A. Computational analysis of lung deformation after murine pneumonectomy. [corrected]. Comput Methods Biomech Biomed Engin 2012; 17:838-44. [PMID: 22978574 PMCID: PMC3527685 DOI: 10.1080/10255842.2012.719606] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In many mammalian species, the removal of one lung (pneumonectomy) is associated with the compensatory growth of the remaining lung. To investigate the hypothesis that parenchymal deformation may trigger lung regeneration, we used microCT scanning to create 3D finite element geometric models of the murine lung pre- and post-pneumonectomy (24 h). The structural correspondence between models was established using anatomic landmarks and an iterative computational algorithm. When compared with the pre-pneumonectomy lung, the post-pneumonectomy models demonstrated significant translation and rotation of the cardiac lobe into the post-pneumonectomy pleural space. 2D maps of lung deformation demonstrated significant heterogeneity; the areas of greatest deformation were present in the subpleural regions of the lobe. Consistent with the previously identified growth patterns, subpleural regions of enhanced deformation are compatible with a mechanical signal - likely involving parenchymal stretch - triggering lung growth.
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Affiliation(s)
- Nenad Filipovic
- Faculty of Mechanical Engineering, University of Kragujevac, Serbia
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
| | - Barry C. Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Dalibor Nikolic
- Faculty of Mechanical Engineering, University of Kragujevac, Serbia
| | - Moritz A. Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Steven J. Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women’s Hospital, Harvard Medical School, Boston MA
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
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Chamoto K, Gibney BC, Ackermann M, Lee GS, Lin M, Konerding MA, Tsuda A, Mentzer SJ. Alveolar macrophage dynamics in murine lung regeneration. J Cell Physiol 2012; 227:3208-15. [PMID: 22105735 DOI: 10.1002/jcp.24009] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In most mammalian species, the removal of one lung results in dramatic compensatory growth of the remaining lung. To investigate the contribution of alveolar macrophages (AMs) to murine post-pneumonectomy lung growth, we studied bronchoalveolar lavage (BAL)-derived AM on 3, 7, 14 and 21 days after left pneumonectomy. BAL demonstrated a 3.0-fold increase in AM (CD45(+), CD11b(-), CD11c(+), F4/80(+), Gr-1(-)) by 14 days after pneumonectomy. Cell cycle flow cytometry of the BAL-derived cells demonstrated an increase in S + G2 phase cells on days 3 (11.3 ± 2.7%) and 7 (12.1 ± 1.8%) after pneumonectomy. Correspondingly, AM demonstrated increased expression of VEGFR1 and MHC class II between days 3 and 14 after pneumonectomy. To investigate the potential contribution of peripheral blood cells to this AM population, parabiotic mice (wild-type/GFP) underwent left pneumonectomy. Analysis of GFP(+) cells in the post-pneumonectomy lung demonstrated that by day 14, less than 1% of the AM population were derived from the peripheral blood. Finally, AM gene transcription demonstrated a significant shift from decreased transcription of angiogenesis-related genes on day 3 to increased transcription on day 7 after pneumonectomy. The increased number of locally proliferating AM, combined with their growth-related gene transcription, suggests that AM actively participate in compensatory lung growth.
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Affiliation(s)
- Kenji Chamoto
- Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Hohendorff B, Weidermann C, Pollinger P, Burkhart KJ, Konerding MA, Prommersberger KJ, Rommens PM. Finger injuries caused by power-operated windows of motor vehicles: an experimental cadaver study. Injury 2012; 43:903-7. [PMID: 22342075 DOI: 10.1016/j.injury.2011.12.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 12/08/2011] [Accepted: 12/12/2011] [Indexed: 02/02/2023]
Abstract
The aim of this experimental cadaver study was to investigate which kinds of lesions could occur in jam events between the glass and seal entry of power-operated motor vehicle side door windows at two different closing forces. Ten hands of fresh cadaver specimens were used. Three different hand positions chosen to simulate real events in which a finger is jammed between the glass and seal entry of the window of a current motor vehicle were examined. The index, middle, ring, and little finger of each hand were separately jammed both at the proximal and distal interphalangeal joint at closing forces of 300 and 500 N with a constant window glass closing speed of 10 cm/s. Macroscopically visible injuries were documented and radiographs of all fingers were obtained in two standard planes. At a closing force of 300 N, contusion marks of the skin, palmar joint instabilities and superficial skin lesions occurred, whilst at 500 N superficial skin lesions, superficial and deep open crush injuries, and fractures were observed. The results of this study experimentally demonstrate the kinds of finger injuries that could be expected in real jam events between the glass and seal entry in automatic power-operated windows.
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Affiliation(s)
- B Hohendorff
- Rhön Klinikum AG, Klinik für Handchirurgie Bad Neustadt Saale, Salzburger Leite 1, D-97616 Bad Neustadt a. d. Saale, Germany.
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Konerding MA, Gibney BC, Houdek J, Chamoto K, Ackermann M, Lee GS, Lin M, Tsuda A, Mentzer SJ. Spatial dependence of alveolar angiogenesis in post-pneumonectomy lung growth. Angiogenesis 2012; 15:23-32. [PMID: 21969134 PMCID: PMC3268013 DOI: 10.1007/s10456-011-9236-y] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 09/19/2011] [Indexed: 01/24/2023]
Abstract
Growth of the remaining lung after pneumonectomy has been observed in many mammalian species; nonetheless, the pattern and morphology of alveolar angiogenesis during compensatory growth is unknown. Here, we investigated alveolar angiogenesis in a murine model of post-pneumonectomy lung growth. As expected, the volume and weight of the remaining lung returned to near-baseline levels within 21 days of pneumonectomy. The percentage increase in lobar weight was greatest in the cardiac lobe (P < 0.001). Cell cycle flow cytometry demonstrated a peak of lung cell proliferation (12.02 ± 1.48%) 6 days after pneumonectomy. Spatial autocorrelation analysis of the cardiac lobe demonstrated clustering of similar vascular densities (positive autocorrelation) that consistently mapped to subpleural regions of the cardiac lobe. Immunohistochemical staining demonstrated increased cell density and enhanced expression of angiogenesis-related factors VEGFA, and GLUT1 in these subpleural regions. Corrosion casting and scanning electron microscopy 3-6 days after pneumonectomy demonstrated subpleural vessels with angiogenic sprouts. The monopodial sprouts appeared to be randomly oriented along the vessel axis with interbranch distances of 11.4 ± 4.8 μm in the regions of active angiogenesis. Also present within the regions of increased vascular density were frequent "holes" or "pillars" consistent with active intussusceptive angiogenesis. The mean pillar diameter was 4.2 ± 3.8 μm, and the pillars were observed in all regions of active angiogenesis. These findings indicate that the process of alveolar construction involves discrete regions of regenerative growth, particularly in the subpleural regions of the cardiac lobe, characterized by both sprouting and intussusceptive angiogenesis.
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Affiliation(s)
- Moritz A. Konerding
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Barry C. Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Jan Houdek
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Kenji Chamoto
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg-University, Mainz, Germany
| | - Grace S. Lee
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Miao Lin
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
| | - Akira Tsuda
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA
| | - Steven J. Mentzer
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA
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Gibney BC, Chamoto K, Lee GS, Simpson DC, Miele LF, Tsuda A, Konerding MA, Wagers A, Mentzer SJ. Cross-circulation and cell distribution kinetics in parabiotic mice. J Cell Physiol 2012; 227:821-8. [PMID: 21503883 DOI: 10.1002/jcp.22796] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Blood-borne nucleated cells participate not only in inflammation, but in tissue repair and regeneration. Because progenitor and stem cell populations have a low concentration in the blood, the circulation kinetics and tissue distribution of these cells is largely unknown. An important approach to tracking cell lineage is the use of fluorescent tracers and parabiotic models of cross-circulation. Here, we investigated the cross-circulation and cell distribution kinetics of C57/B6 GFP(+)/wild-type parabionts. Flow cytometry analysis of the peripheral blood after parabiosis demonstrated no evidence for a "parabiotic barrier" based on cell size or surface characterstics; all peripheral blood cell subpopulations in this study reached equilibrium within 14 days. Whole blood fluorescence analysis indicated that the mean exchange flow rate was 16 µl/h or 0.66% of the circulating blood volume per hour. Studies of peripheral lymphoid organs indicated differential cell distribution kinetics. Some subpopulations, such as CD8(+) and CD11c(+), equilibrated in both lymph nodes and spleen indicating a residence time <28 days; in contrast, other lymphocyte subpopulations, such as B220(+) and CD4(+) cells, had not yet reached equilibrium at 28 days. We conclude that parabiosis can provide important insights into defining tissue distribution, residence times, and recirculating pools using fluorochrome markers of cell lineage.
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Affiliation(s)
- Barry C Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Winkler B, Müller-Schweinitzer E, Elezi F, Grussenmeyer T, Rueter F, Matt P, Konerding MA, Grapow MT, Eckstein FS. Effects of the Novel Polymer Gel LeGoo on Human Internal Thoracic Arteries. Ann Thorac Surg 2011; 92:2235-9. [DOI: 10.1016/j.athoracsur.2011.05.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Revised: 05/01/2011] [Accepted: 05/03/2011] [Indexed: 11/27/2022]
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Chamoto K, Gibney BC, Lee GS, Lin M, Collings-Simpson D, Voswinckel R, Konerding MA, Tsuda A, Mentzer SJ. CD34+ progenitor to endothelial cell transition in post-pneumonectomy angiogenesis. Am J Respir Cell Mol Biol 2011; 46:283-9. [PMID: 21921238 DOI: 10.1165/rcmb.2011-0249oc] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In many species, pneumonectomy triggers compensatory lung growth that results in an increase not only in lung volume, but also in alveolar number. Whether the associated alveolar angiogenesis involves the contribution of blood-borne progenitor cells is unknown. To identify and characterize blood-borne progenitor cells contributing to lung growth after pneumonectomy in mice, we studied wild-type and wild-type/green fluorescence protein (GFP) parabiotic mice after left pneumonectomy. Within 21 days of pneumonectomy, a 3.2-fold increase occurred in the number of lung endothelial cells. This increase in total endothelial cells was temporally associated with a 7.3-fold increase in the number of CD34(+) endothelial cells. Seventeen percent of the CD34(+) endothelial cells were actively proliferating, compared with only 4.2% of CD34(-) endothelial cells. Using wild-type/GFP parabiotic mice, we demonstrated that 73.4% of CD34(+) cells were derived from the peripheral blood. Furthermore, lectin perfusion studies demonstrated that CD34(+) cells derived from peripheral blood were almost uniformly incorporated into the lung vasculature. Finally, CD34(+) endothelial cells demonstrated a similar profile, but had enhanced transcriptional activity relative to CD34(-) endothelial cells. We conclude that blood-borne CD34(+) endothelial progenitor cells, characterized by active cell division and an amplified transcriptional signature, transition into resident endothelial cells during compensatory lung growth.
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Affiliation(s)
- Kenji Chamoto
- Division of Thoracic Surgery, Brigham and Women's Hospital, Room 259, Boston, MA 02115, USA
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Hohendorff B, Weidermann C, Pollinger P, Burkhart KJ, Konerding MA, Prommersberger KJ, Rommens PM. Entrapment of adult fingers between window glass and seal entry of a motor vehicle side door: an experimental study for investigation of the force at the subjective pain threshold. J Biomech 2011; 44:2158-61. [PMID: 21601859 DOI: 10.1016/j.jbiomech.2011.05.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2011] [Revised: 05/06/2011] [Accepted: 05/07/2011] [Indexed: 10/18/2022]
Abstract
In modern motor vehicles with automatic power windows, a potential hazard exists for jam events of fingers between the window glass and seal entry. This study determined entrapment forces acting on adult fingers at the subjective maximum pain threshold during entrapment in such windows. The length and the girth of the proximal and distal interphalangeal joints of the triphalangeal fingers of the right hands of 109 participants (60 men, 49 women) were measured; the diameter was calculated from girth, which was assumed to be circular. The automatic power window system of a motor vehicle side door was changed to a mechanical system. During entrapment the force distributed across the four proximal interphalangeal joints (PIPs), and separately on the proximal interphalangeal (iPIP) and then the distal interphalangeal (iDIP) joints of the index finger was measured using a customized force sensor. The maximum bearable entrapment force was 97.2 ± 51.8 N for the PIPs, 43.4 ± 19.9 N for the iPIP, and 36.9 ± 17.8 N for the iDIP. The positive correlation between finger diameter and maximum entrapment force was significant. Particularly with regard to the risk to children's fingers, the 100 N statutory boundary value for closing force of electronic power windows should be reduced.
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Affiliation(s)
- B Hohendorff
- Rhön Klinikum AG, Klinik für Handchirurgie Bad Neustadt Saale, Salzburger Leite 1, D-97616 Bad Neustadt a. d. Saale, Germany.
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Gibney BC, Lee GS, Houdek JP, Lin M, Miele LF, Chamoto K, Konerding MA, Tsuda A, Mentzer SJ. Dynamic determination of oxygenation and lung compliance in murine pneumonectomy. Exp Lung Res 2011; 37:301-9. [PMID: 21574875 DOI: 10.3109/01902148.2011.561399] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Thoracic surgical procedures in mice have been applied to a wide range of investigations, but little is known about the murine physiologic response to pulmonary surgery. Using continuous arterial oximetry monitoring and the FlexiVent murine ventilator, the authors investigated the effect of anesthesia and pneumonectomy on mouse oxygen saturation and lung mechanics. Sedation resulted in a dose-dependent decline of oxygen saturation that ranged from 55% to 82%. Oxygen saturation was restored by mechanical ventilation with increased rate and tidal volumes. In the mouse strain studied, optimal ventilatory rates were a rate of 200/minute and a tidal volume of 10 mL/kg. Sustained inflation pressures, referred to as a "recruitment maneuver," improved lung volumes, lung compliance, and arterial oxygenation. In contrast, positive end-expiratory pressure (PEEP) had a detrimental effect on oxygenation; an effect that was ameliorated after pneumonectomy. These results confirm that lung volumes in the mouse are dynamically determined and suggest a threshold level of mechanical ventilation to maintain perioperative oxygen saturation.
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Affiliation(s)
- Barry C Gibney
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Klein MO, Bijelic A, Ziebart T, Koch F, Kämmerer PW, Wieland M, Konerding MA, Al-Nawas B. Submicron scale-structured hydrophilic titanium surfaces promote early osteogenic gene response for cell adhesion and cell differentiation. Clin Implant Dent Relat Res 2011; 15:166-75. [PMID: 21682843 DOI: 10.1111/j.1708-8208.2011.00339.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND AND PURPOSE Titanium (Ti) surface roughness and surface hydrophilicity are key factors to regulate osteogenic cell responses during dental implant healing. In detail, specific integrin-mediated interactions with the extracellular environment trigger relevant osteogenic cell responses like differentiation and matrix synthesis via transcriptions factors. Aim of this study was to monitor surface-dependent osteogenic cell adhesion dynamics, proliferation, and specific osteogenic cell differentiation over a period of 7 days. MATERIALS AND METHODS Ti disks were manufactured to present smooth pretreatment (PT) surfaces and rough sandblasted/acid-etched (SLA) surfaces. Further processing to isolate the uncontaminated TiO(2) surface from contact with atmosphere provided a highly hydrophilic surface without alteration of the surface topography (modSLA). Tissue culture polystyrene (TCPS) served as control. Human osteogenic cells were cultivated on the respective substrates. After 24 hours, 48 hours, 72 hours, and 7 days, cell morphology on the Ti substrates was visualized by scanning transmission electron microscopy. As a marker of cellular proliferation, cell count was assessed. For the analysis of cell adhesion and differentiation, specific gene expression levels of the integrin subunits β1 and αv, runx-2, collagen type Iα (COL), alkaline phosphatase (AP), and osteocalcin (OC) were obtained by real-time RT-PCR for the respective time points. Data were normalized to internal controls. RESULTS TCPS and PT surfaces preserved a rather immature, dividing osteogenic phenotype (high proliferation rates, low integrin levels, and low specific osteogenic cell differentiation). SLA and especially modSLA surfaces promoted both cell adhesion as well as the maturation of osteogenic precursors into post-mitotic osteoblasts. In detail, during the first 48 hours, modSLA resulted in lowest cell proliferation rates but exhibited highest levels of the investigated integrins, runx-2, COL, AP, and OC. CONCLUSION Our results revealed a strong synergistic effect between submicron-scale roughness and surface hydrophilicity on early osteogenic cell adhesion and maturation.
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Lee GS, Filipovic N, Lin M, Gibney BC, Simpson DC, Konerding MA, Tsuda A, Mentzer SJ. Intravascular pillars and pruning in the extraembryonic vessels of chick embryos. Dev Dyn 2011; 240:1335-43. [PMID: 21448976 DOI: 10.1002/dvdy.22618] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2010] [Indexed: 11/07/2022] Open
Abstract
To investigate the local mechanical forces associated with intravascular pillars and vessel pruning, we studied the conducting vessels in the extraembryonic circulation of the chick embryo. During the development days 13-17, intravascular pillars and blood flow parameters were identified using fluorescent vascular tracers and digital time-series video reconstructions. The geometry of selected vessels was confirmed by corrosion casting and scanning electron microscopy. Computational simulations of pruning vessels suggested that serial pillars form along pre-existing velocity streamlines; blood pressure demonstrated no obvious spatial relationship with the intravascular pillars. Modeling a Reynolds number of 0.03 produced 4 pillars at approximately 20-μm intervals matching the observed periodicity. In contrast, a Reynolds number of 0.06 produced only 2 pillars at approximately 63-μm intervals. Our modeling data indicated that the combination of wall shear stress and gradient of shear predicted the location, direction, and periodicity of developing pillars.
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Affiliation(s)
- Grace S Lee
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Ackermann M, Wolloscheck T, Wellmann A, Li VW, Li WW, Konerding MA. Priming with a combination of proangiogenic growth factors improves wound healing in normoglycemic mice. Int J Mol Med 2011; 27:647-53. [PMID: 21373751 DOI: 10.3892/ijmm.2011.641] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 12/20/2010] [Indexed: 12/19/2022] Open
Abstract
Growth factors and/or angiogenic factors are supposed to improve wound healing. The aim of our study was to evaluate the effects of subcutaneous pretreatment with combinatory proangiogenic factors on wound closure, mechanical properties, vessel density and morphology. Twenty-eight Balb/c mice were divided equally into two groups. A mixture of VEGF (35.0 µg), bFGF (2.5 µg) and PDGF (3.5 µg) was administered subcutaneously 3, 5 and 7 days to 14 mice before full thickness skin punch biopsy wounding, whereas 14 control animals received three injections of 0.2 ml saline solution. Wound sizes were assessed daily and the repaired tissues were harvested 7 days after complete wound closure. Complete closure (≥ 95% healing of initial wound area) was reached in all proangiogenic pretreated animals on day 10, whereas controls needed 13 days for complete closure. Tensile strengths were nearly twofold higher compared to the controls (p ≤ 0.01). The punch biopsy material revealed 4.2-fold higher vessel densities in the proangiogenic pretreated group. On day 17, the vessel densities in the proangiogenic pretreated wounds were also 3.2-fold higher compared to the untreated controls. No significant differences were seen in the collagen ratio. Pretreatment with proangiogenic factors revealed several significant effects on wound healing: faster time to closure, a higher vessel density and a better functional outcome. These results suggest a beneficial effect of pretreatment with combinatory growth factors in mouse skin wounds without impaired wound healing. This might be exploited in further investigations in diabetic healing as a therapeutic approach for elective surgery.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of Johannes Gutenberg University Mainz, Mainz, Germany
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Ackermann M, Carvajal IM, Morse BA, Moreta M, O'Neil S, Kossodo S, Peterson JD, Delventhal V, Marsh HN, Furfine ES, Konerding MA. Adnectin CT-322 inhibits tumor growth and affects microvascular architecture and function in Colo205 tumor xenografts. Int J Oncol 2011; 38:71-80. [PMID: 21109927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
Antiangiogenesis has become a promising pillar in modern cancer therapy. This study investigates the antiangiogenic effects of the PEGylated Adnectin™, CT-322, in a murine Colo-205 xenograft tumor model. CT-322 specifically binds to and blocks vascular endothelial growth factor receptor (VEGFR-2). Adnectins are a novel class of targeted biologics engineered from the 10th domain of human fibronectin. CT-322 treated tumors exhibited a significant reduction in tumor growth of 69%, a 2.8 times lower tumor surface area and fewer necrotic areas. Control tumors showed a 2.36-fold higher microvessel density (MVD) and a 2.42 times higher vessel volume in corrosion casts. The vascular architecture in CT-322-treated tumors was characterized by a strong normalization of vasculature. This was quantified in corrosion casts of CT-322 treated tumors in which the intervascular distance (a reciprocal parameter indicative of vessel density) and the distance between two consecutive branchings were assessed, with these distances being 2.21 times and 2.37 times greater than in controls, respectively. Fluorescence molecular tomography (FMT) equally affirmed the inhibitory effects of CT-322 on tumor vasculature as indicated by a 60% reduction of the vascular probe, AngioSense, accumulating in tumor tissue, as a measurement of vascular permeability. Moreover, AngioSense accumulation was reduced as early as 24 h after starting treatment. The sum of these effects on tumor vasculature illustrates the anti-angiogenic mechanism underlying the antitumor activity of CT-322 and provides support for further evaluation of this Adnectin in combinatorial strategies with standard of care therapies.
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Affiliation(s)
- Maximilian Ackermann
- Institute of Functional & Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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Ackermann M, Wolloscheck T, Wellmann A, Li VW, Li WW, Konerding MA. Priming with a Combination of Proangiogenic Growth Factors Enhances Wound Healing in Streptozotocin-Induced Diabetes in Mice. Eur Surg Res 2011; 47:81-9. [DOI: 10.1159/000328143] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 04/05/2011] [Indexed: 12/12/2022]
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Medinger M, Esser N, Soltau J, Lehmann KM, Konerding MA, Wolloscheck T, Ryan AJ, Drevs J. Antitumor effect of the vascular-disrupting agent ZD6126 in a murine renal cell carcinoma model. Int J Oncol 2010; 38:455-64. [PMID: 21152862 DOI: 10.3892/ijo.2010.867] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 11/03/2010] [Indexed: 11/06/2022] Open
Abstract
ZD6126 is a vascular-disrupting agent that affects the endothelial tubulin cytoskeleton causing selective occlusion of tumor vasculature and extensive tumor cell necrosis. The present study evaluated the antitumor and antivascular activities of ZD6126 in the clinically relevant murine renal cell carcinoma (RENCA) model and also evaluated biological response to therapy using color Doppler imaging as biomarker. Mice were implanted with RENCA tumor cells (day 0) and established tumors were treated with ZD6126 (100 mg/kg i.p.) or vehicle with repeated intermittent doses on day 10, 14 and 18. ZD6126 treatment led to a significant reduction in tumor size and was associated with extensive tumor necrosis and a reduction in tumor blood flow versus controls. MVD increased with intermittent treatment (day 10, 14 and 18). In an additional study, animals were treated at day 19 and quantitative three-dimensional microvascular corrosion casting was performed to enable detailed assessment of the tumor vascular architecture. Corrosion casting showed that tumor vessel architecture is affected by treatment, whereas pre-existing vessels in control tissues are practically not affected. Inter-vessel and inter-branch distances as well as vessel diameters are influenced by treatment. In conclusion, ZD6126 showed potent antitumor efficacy in the RENCA model and our data suggest that decrease in tumor blood flow may be a useful surrogate marker of treatment effect.
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Affiliation(s)
- M Medinger
- Department of Medical Oncology, Tumor Biology Center at the Albert Ludwigs University, Freiburg, Germany.
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46
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Förstemann T, Trzewik J, Holste J, Batke B, Konerding MA, Wolloscheck T, Hartung C. Forces and deformations of the abdominal wall--a mechanical and geometrical approach to the linea alba. J Biomech 2010; 44:600-6. [PMID: 21130459 DOI: 10.1016/j.jbiomech.2010.11.021] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2010] [Revised: 11/11/2010] [Accepted: 11/13/2010] [Indexed: 11/30/2022]
Abstract
Force-elongation responses of the human abdominal wall in the linea alba region were determined by tensile tests in which the linea alba was seen to exhibit a nonlinear elastic, anisotropic behavior as is frequently observed in soft biological tissues. In addition, the geometry of the abdominal wall was determined, based on MRI data. The geometry can be specified by principal radii of curvature in longitudinal of approximately 470 mm and in the transverse direction of about 200 mm. The determined radii agree with values found in other studies. Mechanical stresses, deformations and abdominal pressures for load cases above 6% elongation can be related using Laplace's formula and our constitutive and geometrical findings. Results from uni- and biaxial tensile tests can thus be compared using this model. Calculations confirm that abdominal pressures of approximately 20 kPa correspond to related biaxial forces of about 3.4N/mm in the transverse and 1.5 N/mm in the longitudinal direction. Young's moduli can be calculated with respect to the uniaxial as well as the biaxial loading. At these physiological loadings, a compliance ratio of about 2:1 between the longitudinal and transversal directions is found. Young's moduli of about 50 kPa occur in transversal direction and of about 20 kPa in longitudinal direction at transverse and longitudinal strains both in the order of 6%. These findings coincide with results from other investigations in which the properties of the abdominal wall have been examined.
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Affiliation(s)
- T Förstemann
- European Competence Center of Healthcare Engineering, Im Klampfeld 12, 30966 Hemmingen, Germany.
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Oertel JMK, Vulcu S, Schroeder HWS, Konerding MA, Wagner W, Gaab MR. Endoscopic transventricular third ventriculostomy through the lamina terminalis. J Neurosurg 2010; 113:1261-9. [DOI: 10.3171/2010.6.jns09491] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Object
Endoscopic third ventriculostomy (ETV) has become a well-accepted option for obstructive hydrocephalus. However, standard ventriculostomy at the floor of the third ventricle might not be feasible under certain conditions. Here, the authors report in detail on their initial experience with an alternative option of endoscopic ventriculostomy through the lamina terminalis via a transventricular route.
Methods
Endoscopic third ventriculostomy through the lamina terminalis from a transventricular transforaminal route was evaluated in 4 cadaveric human heads and in 4 clinical cases.
Results
In all 4 human cadavers, an opening of the lamina terminalis via a transventricular approach could be achieved without injury to either the optic chiasm or the anterior cerebral arteries. In the 4 clinical cases, an accurate and reliable ventriculostomy was performed at the lamina terminalis. The bur hole was placed directly at the coronal suture 2 cm lateral from the midline. After identifying the optic chiasm and the anterior cerebral arteries, a blunt perforation was made just anterior to the optic chiasm by using perforation forceps and a balloon catheter. After the opening, the stoma was inspected with a 0° and 30° rod lens endoscope, and its patency as well as the preservation of vessels and optic nerves was checked. No complications occurred, although all patients suffered from a clinically silent fornical contusion at the foramen of Monro.
Conclusions
Endoscopic opening of the lamina terminalis via a transventricular transforaminal route appears to be feasible. No complications were observed. Although no conclusions on the clinical success rate can be drawn, the reliable anatomical opening and known success rate for anterior subfrontal approaches suggest that the technique represents an alternative in a small subgroup of patients in whom a standard ETV cannot be performed.
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Affiliation(s)
- Joachim M. K. Oertel
- 1Neurochirurgische Klinik und Poliklinik, Universitaetsmedizin, Johannes Gutenberg Universität, Mainz
| | - Sonja Vulcu
- 1Neurochirurgische Klinik und Poliklinik, Universitaetsmedizin, Johannes Gutenberg Universität, Mainz
| | - Henry W. S. Schroeder
- 2Klinik und Poliklinik für Neurochirurgie, Ernst Moritz Arndt Universitaet, Greifswald
| | - Moritz A. Konerding
- 3Institut für Anatomie und Zellbiologie, Universitaetsmedizin, Johannes Gutenberg Universität, Mainz; and
| | - Wolfgang Wagner
- 1Neurochirurgische Klinik und Poliklinik, Universitaetsmedizin, Johannes Gutenberg Universität, Mainz
| | - Michael R. Gaab
- 4Neurochirurgische Klinik und Poliklinik, Nordstadtkrankenhaus, Klinikum Region Hannover, Germany
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Jerkic M, Peter M, Ardelean D, Fine M, Konerding MA, Letarte M. Dextran sulfate sodium leads to chronic colitis and pathological angiogenesis in Endoglin heterozygous mice. Inflamm Bowel Dis 2010; 16:1859-70. [PMID: 20848471 PMCID: PMC2959118 DOI: 10.1002/ibd.21288] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Pathological angiogenesis is an intrinsic component of chronic intestinal inflammation, which results in remodeling and expansion of the gut microvascular bed. Endoglin is essential for endothelial cell function and physiological angiogenesis. In this study we investigated its potential role in the regulation of inflammation by testing the response of Endoglin heterozygous (Eng(+/-)) mice to experimental colitis. METHODS C57BL/6 Eng(+/-) and littermate control mice drank water supplemented with 3% dextran sulfate sodium (DSS) for 5 days and were monitored for up to 26 days for clinical signs of colitis. Inflammation, crypt damage, and angiogenic index were scored on histological sections of distal colon. Levels of the vascular endothelial growth factor (VEGF) and angiopoietins were measured by real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and/or Western blots. Vascular permeability was assessed using Evans Blue. RESULTS Eng(+/-) and control mice developed acute colitis, which peaked at day 9. While control mice recovered by days 19-26, Eng(+/-) mice progressed to chronic colitis and showed numerous vascular protrusions penetrating into the serosa of the inflamed distal colon. Prior to DSS induction, VEGF levels and vascular permeability were higher in the distal colon of Eng(+/-) mice, while angiopoietin 1 and 2 levels were unchanged. In the chronic phase of colitis, VEGF levels were increased in both groups of mice and remained significantly higher in the Eng(+/-) mice. CONCLUSIONS Higher VEGF levels and increased vascular permeability in the distal colon may predispose Eng(+/-) mice to progress to chronic and persistent bowel inflammation, associated with pathological angiogenesis.
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Affiliation(s)
- Mirjana Jerkic
- Molecular Structure and Function Program, Hospital for Sick Children,The Heart and Stroke Foundation Richard Lewar Centre of Excellence, University of Toronto
| | - Madonna Peter
- Molecular Structure and Function Program, Hospital for Sick Children,Department of Immunology, University of Toronto
| | - Daniela Ardelean
- Molecular Structure and Function Program, Hospital for Sick Children,Division of Pediatric Rheumatology, Hospital for Sick Children
| | | | | | - Michelle Letarte
- Molecular Structure and Function Program, Hospital for Sick Children,The Heart and Stroke Foundation Richard Lewar Centre of Excellence, University of Toronto,Department of Immunology, University of Toronto
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Konerding MA, Turhan A, Ravnic DJ, Lin M, Fuchs C, Secomb TW, Tsuda A, Mentzer SJ. Inflammation-induced intussusceptive angiogenesis in murine colitis. Anat Rec (Hoboken) 2010; 293:849-57. [PMID: 20225210 DOI: 10.1002/ar.21110] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Intussusceptive angiogenesis is a morphogenetic process that forms new blood vessels by the division of a single blood vessel into two lumens. Here, we show that this process of intraluminal division participates in the inflammation-induced neovascularization associated with chemically induced murine colitis. In studies of both acute (4-7 days) and chronic (28-31 days) colitis, intravital microscopy of intravascular tracers demonstrated a twofold reduction in blood flow velocity. In the acute colitis model, the decreased velocity was associated with marked dilatation of the mucosal plexus. In contrast, chronic inflammation was associated with normal caliber vessels and duplication (and triplication) of the quasi-polygonal mucosal plexus. Scanning electron microscopy (SEM) of intravascular corrosion casts suggested that pillar formation and septation, previously linked to the morphogenetic process of intussusceptive angiogenesis, were present within days of the onset of inflammation. Four weeks after the onset of inflammation, SEM of vascular corrosion casts demonstrated replication of the mucosal plexus without significant evidence of sprouting angiogenesis. These data suggest that mucosal capillaries have comparable aggregate cross-sectional area in acute and chronic colitis; however, there is a significant increase in functional capillary density in chronic colitis. We conclude that intussusceptive angiogenesis is a fundamental mechanism of microvascular adaptation to prolonged inflammation.
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Affiliation(s)
- Moritz A Konerding
- Institute of Anatomy and Cell Biology, University Medical Center, Johannes Gutenberg-University, Mainz, Germany
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50
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Lee GS, Filipovic N, Miele LF, Lin M, Simpson DC, Giney B, Konerding MA, Tsuda A, Mentzer SJ. Blood flow shapes intravascular pillar geometry in the chick chorioallantoic membrane. J Angiogenes Res 2010; 2:11. [PMID: 20609245 PMCID: PMC2911408 DOI: 10.1186/2040-2384-2-11] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 07/07/2010] [Indexed: 11/16/2022]
Abstract
The relative contribution of blood flow to vessel structure remains a fundamental question in biology. To define the influence of intravascular flow fields, we studied tissue islands--here defined as intravascular pillars--in the chick chorioallantoic membrane. Pillars comprised 0.02 to 0.5% of the vascular system in 2-dimensional projection and were predominantly observed at vessel bifurcations. The bifurcation angle was generally inversely related to the length of the pillar (R = -0.47, P < .001). The pillar orientation closely mirrored the axis of the dominant vessel with an average variance of 5.62 ± 6.96 degrees (p = .02). In contrast, the variance of pillar orientation relative to nondominant vessels was 36.78 ± 21.33 degrees (p > .05). 3-dimensional computational flow simulations indicated that the intravascular pillars were located in regions of low shear stress. Both wide-angle and acute-angle models mapped the pillars to regions with shear less than 1 dyn/cm2. Further, flow modeling indicated that the pillars were spatially constrained by regions of higher wall shear stress. Finally, the shear maps indicated that the development of new pillars was limited to regions of low shear stress. We conclude that mechanical forces produced by blood flow have both a limiting and permissive influence on pillar development in the chick chorioallantoic membrane.
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Affiliation(s)
- Grace S Lee
- Laboratory of Adaptive and Regenerative Biology, Brigham & Women's Hospital, Harvard Medical School, Boston MA, USA.
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