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Markel K, Novak V, Bowen BP, Tian Y, Chen YC, Sirirungruang S, Zhou A, Louie KB, Northen TR, Eudes A, Scheller HV, Shih PM. Cynipid wasps systematically reprogram host metabolism and restructure cell walls in developing galls. Plant Physiol 2024; 195:698-712. [PMID: 38236304 DOI: 10.1093/plphys/kiae001] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/14/2023] [Accepted: 11/14/2023] [Indexed: 01/19/2024]
Abstract
Many insects have evolved the ability to manipulate plant growth to generate extraordinary structures called galls, in which insect larva can develop while being sheltered and feeding on the plant. In particular, cynipid (Hymenoptera: Cynipidae) wasps have evolved to form morphologically complex galls and generate an astonishing array of gall shapes, colors, and sizes. However, the biochemical basis underlying these remarkable cellular and developmental transformations remains poorly understood. A key determinant in plant cellular development is cell wall deposition that dictates the physical form and physiological function of newly developing cells, tissues, and organs. However, it is unclear to what degree cell walls are restructured to initiate and support the formation of new gall tissue. Here, we characterize the molecular alterations underlying gall development using a combination of metabolomic, histological, and biochemical techniques to elucidate how valley oak (Quercus lobata) leaf cells are reprogrammed to form galls. Strikingly, gall development involves an exceptionally coordinated spatial deposition of lignin and xylan to form de novo gall vasculature. Our results highlight how cynipid wasps can radically change the metabolite profile and restructure the cell wall to enable the formation of galls, providing insights into the mechanism of gall induction and the extent to which plants can be entirely reprogrammed to form unique structures and organs.
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Affiliation(s)
- Kasey Markel
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Vlastimil Novak
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Benjamin P Bowen
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
- Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yang Tian
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Yi-Chun Chen
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Sasilada Sirirungruang
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
- Center for Biomolecular Structure, Function and Application, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Andy Zhou
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Katherine B Louie
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
- Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Trent R Northen
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
- Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Aymerick Eudes
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Henrik V Scheller
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
| | - Patrick M Shih
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94608, USA
- Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Innovative Genomics Institute, University of California, Berkeley, CA 94720, USA
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2
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Novak V, Andeer PF, Bowen BP, Ding Y, Zhalnina K, Hofmockel KS, Tomaka C, Harwood TV, van Winden MCM, Golini AN, Kosina SM, Northen TR. Reproducible growth of Brachypodium in EcoFAB 2.0 reveals that nitrogen form and starvation modulate root exudation. Sci Adv 2024; 10:eadg7888. [PMID: 38170767 PMCID: PMC10776018 DOI: 10.1126/sciadv.adg7888] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 11/20/2023] [Indexed: 01/05/2024]
Abstract
Understanding plant-microbe interactions requires examination of root exudation under nutrient stress using standardized and reproducible experimental systems. We grew Brachypodium distachyon hydroponically in fabricated ecosystem devices (EcoFAB 2.0) under three inorganic nitrogen forms (nitrate, ammonium, and ammonium nitrate), followed by nitrogen starvation. Analyses of exudates with liquid chromatography-tandem mass spectrometry, biomass, medium pH, and nitrogen uptake showed EcoFAB 2.0's low intratreatment data variability. Furthermore, the three inorganic nitrogen forms caused differential exudation, generalized by abundant amino acids-peptides and alkaloids. Comparatively, nitrogen deficiency decreased nitrogen-containing compounds but increased shikimates-phenylpropanoids. Subsequent bioassays with two shikimates-phenylpropanoids (shikimic and p-coumaric acids) on soil bacteria or Brachypodium seedlings revealed their distinct capacity to regulate both bacterial and plant growth. Our results suggest that (i) Brachypodium alters exudation in response to nitrogen status, which can affect rhizobacterial growth, and (ii) EcoFAB 2.0 is a valuable standardized plant research tool.
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Affiliation(s)
- Vlastimil Novak
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Peter F. Andeer
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Benjamin P. Bowen
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- The DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yezhang Ding
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kateryna Zhalnina
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kirsten S. Hofmockel
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99354, USA
- Department of Agronomy, Iowa State University, Ames, IA 50011, USA
| | - Connor Tomaka
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Thomas V. Harwood
- The DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | | | - Amber N. Golini
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Suzanne M. Kosina
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Trent R. Northen
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- The DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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3
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Novak V, Hrabalek L, Schovanek J, Frysak Z, Ijisesan Perryova RT, Pohlodek D. Results of surgical therapy of functioning pituitary adenomas. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2023. [PMID: 37737300 DOI: 10.5507/bp.2023.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 09/23/2023] Open
Abstract
INTRODUCTION Functioning pituitary adenomas lead to substantial morbidity and increased mortality associated with typical endocrine syndromes. Surgical therapy is an integral part of the management of these tumours. The aim of this study was to evaluate the results of surgical transnasal procedures in patients with functioning pituitary adenomas who underwent the surgery at the Department of Neurosurgery, University Hospital Olomouc. METHODS Patients with functioning pituitary adenoma (ACTH, GH, PRL) were indicated for surgery. All patients underwent preoperative and postoperative endocrinological examination and laboratory tests to assess excessive or deficient hormonal production and imaging examination. RESULTS The cohort consisted of 58 patients, 33 of whom were women and 25 men. The age range was 12-77 years (mean age 47.6 years). Microadenoma was diagnosed in 58.6% of patients and macroadenoma in 41.4% of patients. The most common hypersecretory syndrome was excessive production of growth hormone (56.9%), followed by excessive production of adrenocorticotropic hormone (24.1%) and prolactin (12.1%). In the group with excessive production of ACTH, complete remission was achieved after the first surgery in 78.6% of cases (72.8% for microadenomas (8) and 100% (3) cases in macroadenomas); in the group with excessive GH production in 51.4% (63.2% (7) in microadenomas and 46.2% (12) cases in macroadenomas). In the group with excessive production of PRL, it was 57.1% (100% (2) in microadenomas and 40% (2) cases in macroadenomas). CONCLUSION Surgical therapy in the presented cohort led to the normalisation of hormonal excessive production in 58.6% of cases. A combination of drug therapy and radiotherapeutic methods was necessary in the remaining cases to achieve hormonal remission.
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Affiliation(s)
- Vlastimil Novak
- Department of Neurosurgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Lumir Hrabalek
- Department of Neurosurgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Jan Schovanek
- Department of Internal Medicine III - Nephrology, Rheumatology and Endocrinology, University Hospital Olomouc and Faculty of Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Zdenek Frysak
- Department of Internal Medicine III - Nephrology, Rheumatology and Endocrinology, University Hospital Olomouc and Faculty of Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Racheal Temitope Ijisesan Perryova
- Department of Neurosurgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Daniel Pohlodek
- Department of Neurosurgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
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Binenbaum J, Wulff N, Camut L, Kiradjiev K, Anfang M, Tal I, Vasuki H, Zhang Y, Sakvarelidze-Achard L, Davière JM, Ripper D, Carrera E, Manasherova E, Ben Yaakov S, Lazary S, Hua C, Novak V, Crocoll C, Weinstain R, Cohen H, Ragni L, Aharoni A, Band LR, Achard P, Nour-Eldin HH, Shani E. Gibberellin and abscisic acid transporters facilitate endodermal suberin formation in Arabidopsis. Nat Plants 2023; 9:785-802. [PMID: 37024660 PMCID: PMC7615257 DOI: 10.1038/s41477-023-01391-3] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 03/09/2023] [Indexed: 05/04/2023]
Abstract
The plant hormone gibberellin (GA) regulates multiple developmental processes. It accumulates in the root elongating endodermis, but how it moves into this cell file and the significance of this accumulation are unclear. Here we identify three NITRATE TRANSPORTER1/PEPTIDE TRANSPORTER (NPF) transporters required for GA and abscisic acid (ABA) translocation. We demonstrate that NPF2.14 is a subcellular GA/ABA transporter, presumably the first to be identified in plants, facilitating GA and ABA accumulation in the root endodermis to regulate suberization. Further, NPF2.12 and NPF2.13, closely related proteins, are plasma membrane-localized GA and ABA importers that facilitate shoot-to-root GA12 translocation, regulating endodermal hormone accumulation. This work reveals that GA is required for root suberization and that GA and ABA can act non-antagonistically. We demonstrate how the clade of transporters mediates hormone flow with cell-file-specific vacuolar storage at the phloem unloading zone, and slow release of hormone to induce suberin formation in the maturation zone.
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Affiliation(s)
- Jenia Binenbaum
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Nikolai Wulff
- DynaMo Center of Excellence, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Lucie Camut
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France
| | - Kristian Kiradjiev
- Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, UK
| | - Moran Anfang
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Iris Tal
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Himabindu Vasuki
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Yuqin Zhang
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Lali Sakvarelidze-Achard
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France
| | - Jean-Michel Davière
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France
| | - Dagmar Ripper
- ZMBP-Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
| | - Esther Carrera
- Instituto de Biología Molecular y Celular de Plantas, CSIC-UPV, Valencia, Spain
| | - Ekaterina Manasherova
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization (ARO), Volcani Center, Rishon Lezion, Israel
| | - Shir Ben Yaakov
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Shani Lazary
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Chengyao Hua
- DynaMo Center of Excellence, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Vlastimil Novak
- Plant Nutrients and Food Quality Research Group, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Christoph Crocoll
- DynaMo Center of Excellence, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Roy Weinstain
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Hagai Cohen
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization (ARO), Volcani Center, Rishon Lezion, Israel
| | - Laura Ragni
- ZMBP-Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Leah R Band
- Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK.
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, UK.
| | - Patrick Achard
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France.
| | - Hussam Hassan Nour-Eldin
- DynaMo Center of Excellence, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark.
| | - Eilon Shani
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel.
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Einarsson E, Pierantoni M, Novak V, Svensson J, Isaksson H, Englund M. Phase-contrast enhanced synchrotron micro-tomography of human meniscus tissue. Osteoarthritis Cartilage 2022; 30:1222-1233. [PMID: 35750240 DOI: 10.1016/j.joca.2022.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [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] [Received: 02/03/2022] [Revised: 05/27/2022] [Accepted: 06/13/2022] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To investigate the feasibility of synchrotron radiation-based phase contrast enhanced micro-computed tomography (SR-PhC-μCT) for imaging of human meniscus. Quantitative parameters related to fiber orientation and crimping were evaluated as potential markers of tissue degeneration. DESIGN Human meniscus specimens from 10 deceased donors were prepared using different preparation schemes: fresh frozen and thawed before imaging or fixed and paraffin-embedded. The samples were imaged using SR-PhC-μCT with an isotropic voxel size of 1.625 μm. Image quality was evaluated by visual inspection and spatial resolution. Fiber voxels were defined using a grey level threshold and a structure tensor analysis was applied to estimate collagen fiber orientation. The area at half maximum (FAHM) was calculated from angle histograms to quantify orientation distribution. Crimping period was calculated from the power spectrum of image profiles of crimped fibers. Parameters were compared to degenerative stage as evaluated by Pauli histopathological scoring. RESULTS Image quality was similar between frozen and embedded samples and spatial resolutions ranged from 5.1 to 5.8 μm. Fiber structure, including crimping, was clearly visible in the images. Fibers appeared to be less organized closer to the tip of the meniscus. Fiber density might decrease slightly with degeneration. FAHM and crimping period did not show any clear association with histopathological scoring. CONCLUSION SR-PhC-μCT is a feasible technique for high-resolution 3D imaging of fresh frozen meniscus tissue. Further work is needed to establish quantitative parameters that relate to tissue degeneration, but this imaging technique is promising for future studies of meniscus structure and biomechanical response.
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Affiliation(s)
- E Einarsson
- Medical Radiation Physics, Department of Translational Medicine, Lund University, Malmö, Sweden; Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
| | - M Pierantoni
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - V Novak
- Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland
| | - J Svensson
- Medical Radiation Physics, Department of Translational Medicine, Lund University, Malmö, Sweden; Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden
| | - H Isaksson
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - M Englund
- Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
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Aponte Becerra L, Galindo Mendez B, Khan F, Lioutas V, Novak P, Mantzoros CS, Ngo LH, Novak V. Safety of Intranasal Insulin in Type 2 Diabetes on Systemic Insulin: A Double-Blinded Placebo-Controlled Sub-Study of Memaid Trial. Arch Diabetes Obes 2022; 4:403-415. [PMID: 35903156 PMCID: PMC9328174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
AIMS To determine safety of intranasal insulin (INI) in MemAID trial participants with diabetes treated with systemic insulins. MATERIALS AND METHODS This randomized, double-blinded trial consisted of 24-week INI or placebo treatment once daily and 24-week follow-up. Safety outcomes were: 1) Short-term effects on glycemic variability, hypoglycemic episodes on continuous glucose monitoring (CGM) at baseline and on-treatment. 2) Long-term effects on glucose metabolism and weight on INI/placebo treatment and post-treatment follow-up. Of 86 screened subjects, 14 were randomized, 9 (5 INI, 4 Placebo) completed CGM at baseline and on-treatment, and 5 (2 INI, 3 Placebo) completed treatment and follow-up. RESULTS INI was safe and was not associated with serious adverse events, hypoglycemic episodes or weight gain. INI administration did not acutely affect capillary glucose. Glycemic variability on CGM decreased with INI, compared to baseline. On INI treatment, there was a long-term trend toward lower HbA1c, plasma glucose and insulin. No interactions with subcutaneous insulins were observed. CONCLUSIONS INI is safe in older people with diabetes treated with systemic insulins, and it is not associated with adverse events, hypoglycemia or weight gain. Future studies are needed to determine whether INI administration can reduce glycemic variability, improve insulin sensitivity and thus potentially lessen diabetes burden in this population.
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Affiliation(s)
- L Aponte Becerra
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, USA
- Department of Internal Medicine, Jackson Memorial Hospital, University of Miami, Miami, FL, USA
| | - B Galindo Mendez
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, USA
| | - F Khan
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, USA
| | - V Lioutas
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, USA
| | - P Novak
- Department of Neurology, Brigham and Women's Faulkner Hospital, Harvard Medical School, Boston, MA, USA
| | - C S Mantzoros
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston MA and Department of Medicine, Boston VA Healthcare System, Harvard Medical School, Boston, MA, USA
| | - L H Ngo
- Department of Medicine, Beth Israel Deaconess Medical Center and School of Public Health, Harvard Medical School, Boston, MA, USA
| | - V Novak
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, USA
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Shurko N, Danysh T, Mylyashkevich S, Novak V. M007 Preparative purification of albumin: Current status and trends. Clin Chim Acta 2022. [DOI: 10.1016/j.cca.2022.04.297] [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: 11/03/2022]
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Mie A, Novak V, Franko MA, Bügel SG, Laursen KH. Fertilizer Type Affects Stable Isotope Ratios of Nitrogen in Human Blood Plasma─Results from Two-Year Controlled Agricultural Field Trials and a Randomized Crossover Dietary Intervention Study. J Agric Food Chem 2022; 70:3391-3399. [PMID: 35263104 PMCID: PMC8949720 DOI: 10.1021/acs.jafc.1c04418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 02/10/2022] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
The stable nitrogen isotope ratio δ15N is used as a marker of dietary protein sources in blood. Crop fertilization strategies affect δ15N in plant foods. In a double-blinded randomized cross-over dietary intervention trial with 33 participants, we quantified the effect of fertilizer type (conventional: synthetic fertilizer and organic: animal or green manure) on δ15N in blood plasma. At study baseline, plasma δ15N was +9.34 ± 0.29‰ (mean ± standard deviation). After 12 days intervention with a diet based on crops fertilized with animal manure, plasma δ15N was shifted by +0.27 ± 0.04‰ (mean ± standard error) compared to synthetic fertilization and by +0.22 ± 0.04‰ compared to fertilization with green manure (both p < 0.0001). Accordingly, differences in the δ15N values between fertilizers are propagated to the blood plasma of human consumers. The results indicate a need to consider agricultural practices when using δ15N as a dietary biomarker.
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Affiliation(s)
- Axel Mie
- Department
of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm 11883, Sweden
- Department
of Environmental Science, Stockholm University, Stockholm 106 91, Sweden
| | - Vlastimil Novak
- Plant
Nutrients and Food Quality Research Group, Plant and Soil Science
Section and Copenhagen Plant Science Centre, Department of Plant and
Environmental Sciences, University of Copenhagen, Frederiksberg C 1871, Denmark
| | - Mikael Andersson Franko
- Department
of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm 11883, Sweden
| | - Susanne Gjedsted Bügel
- Preventive
and Clinical Nutrition, Department of Nutrition, Exercise and Sports, University of Copenhagen, Frederiksberg C 1871, Denmark
| | - Kristian Holst Laursen
- Plant
Nutrients and Food Quality Research Group, Plant and Soil Science
Section and Copenhagen Plant Science Centre, Department of Plant and
Environmental Sciences, University of Copenhagen, Frederiksberg C 1871, Denmark
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Novak V, Hrabalek L, Hoza J, Tuckova L, Pohlodek D. Transnasal endoscopic surgery of sphenoid meningocele associated with pituitary adenoma. A case report. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2021; 166:343-346. [PMID: 34446940 DOI: 10.5507/bp.2021.052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 08/11/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Transsphenoid meningoencephalocele is a congenital anomaly formed by herniation of an ependyma delimited sac through a bony defect into the sphenoid sinus. The sac contains cerebrospinal fluid and neurovascular structures. The prevalence of transsphenoid meningoencephalocele in the adult population is rare. It usually manifests as nasal liquorrhoea. METHODS AND RESULTS This case report presents an adult male who underwent surgery due to suspected pituitary macroadenoma. The surgery was performed endoscopically via the transnasal approach with a surprising finding of true transsphenoid meningoencephalocele. Ectopic solid tissue was found in the sphenoid sinus in which pituitary adenoma was histologically confirmed. CONCLUSION This paper presents a previously unpublished combination of true transsphenoid meningoencephalocele and pituitary adenoma in an adult individual.
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Affiliation(s)
- Vlastimil Novak
- Department of Neurosurgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Lumir Hrabalek
- Department of Neurosurgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Jiri Hoza
- Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Lucie Tuckova
- Institute of Clinical and Molecular Pathology, University Hospital Olomouc and Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
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Novak V, Khatri PK, Laursen KH. The oxygen isotopic signature of soil- and plant-derived sulphate is controlled by fertilizer type and water source. Plant Cell Environ 2021; 44:203-215. [PMID: 32844439 DOI: 10.1111/pce.13877] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 08/19/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
The oxygen isotope signature of sulphate (δ18 Osulphate ) is increasingly used to study nutritional fluxes and sulphur transformation processes in a variety of natural environments. However, mechanisms controlling the δ18 Osulphate signature in soil-plant systems are largely unknown. The objective of this study was to determine key factors, which affect δ18 Osulphate values in soil and plants. The impact of an 18 O-water isotopic gradient and different types of fertilizers was investigated in a soil incubation study and a radish (Raphanus sativus L.) greenhouse growth experiment. Water provided 31-64% of oxygen atoms in soil sulphate formed via mineralization of organic residues (green and chicken manures) while 49% of oxygen atoms were derived from water during oxidation of elemental sulphur. In contrast, δ18 Osulphate values of synthetic fertilizer were not affected by soil water. Correlations between soil and plant δ18 Osulphate values were controlled by water δ18 O values and fertilizer treatments. Additionally, plant δ34 S data showed that the sulphate isotopic composition of plants is a function of S assimilation. This study documents the potential of using compound-specific isotope ratio analysis for investigating and tracing fertilization strategies in agricultural and environmental studies.
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Affiliation(s)
- Vlastimil Novak
- Plant Nutrients and Food Quality Research Group, Plant and Soil Science Section and Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Purna Kumar Khatri
- Plant Nutrients and Food Quality Research Group, Plant and Soil Science Section and Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Kristian Holst Laursen
- Plant Nutrients and Food Quality Research Group, Plant and Soil Science Section and Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
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Trevino JT, Quispe RC, Khan F, Novak V. Non-Invasive Strategies for Nose-to-Brain Drug Delivery. J Clin Trials 2020; 10:439. [PMID: 33505777 PMCID: PMC7836101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Intranasal drug administration is a promising method for delivering drugs directly to the brain. Animal studies have described pathways and potential brain targets, but nose-to-brain delivery and treatment efficacy in humans remains debated. We describe the proposed pathways and barriers for nose-to-brain drug delivery in humans, drug properties that influence central nervous system delivery, clinically tested methods to enhance absorption, and the devices used in clinical trials. This review compiles the available evidence for nose-to-brain drug delivery in humans and summarizes the factors involved in nose-to-brain drug delivery.
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Affiliation(s)
- J T Trevino
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - R C Quispe
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - F Khan
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - V Novak
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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12
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Gorbatyuk O, Soleiko D, Kurylo H, Soleiko N, Novak V. [URGENT SURGICAL OPERATIONS FOR CROHN'S DISEASE IN CHILDREN]. Georgian Med News 2020:61-66. [PMID: 33130648] [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] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Aim - the improvement of treatment results of patients with complicated Crohn's disease based on study and analysis of own results of surgical interventions. Since 2008 to 2020 years 23 patients at the age 1,5-17 years old with Crohn's disease in 3 pediatric surgical hospitals have been observed. The article presents the analysis of surgical treatment of these patients with complications of main pathology. Diagnostics is integrated and includes clinical and laboratorian examination of patients, X-ray, endoscopic, sonography methods of examination and morphological research method of clinical biopsy. Complications of Crohn's disease were presented by intestinal obstructions (34,78% of cases), intestinal perforations (26,09%), acute appendicitis with mesadenitis (13,04%), intraabdominal abscesses (8,7%), intestinal hemorragia from inflammatory wart (4,35%), perianal inflammatory complications with fistulas (13,04%). The article has covered all possible methods of surgical operations depending on the type of complication. The most frequent surgical interventions were resections of intestinal stenosis with formation of intestinal stomas. The majority of patients have achieved good results after surgical interventions. 5 (23,81%) patients have got a relaparotomias because of such postoperative complications as anastomotic failure (1), recurrence of intestinal perforation (2) and recurrence of intestinal obstruction (2). Mortality has not been observed. Conclusions. 1. Because of Crohn's disease is a progressive disease, the opportunity of emergence of acute surgical complications of this pathology preserves. Our data show that urgent surgical complications of Crohn's disease in 47,83% of patients were the first manifestation of the disease, which was diagnosed during treatment and verified morphologically in the postoperative period. 2. In most cases surgical complications were intestinal obstruction (34,78% cases) and intestinal perforations (26,09%), and the most frequent surgical interventions for Crohn's disease in children were resections of the affected areas of the intestine with formation of intestinal stomas. 3. The modern tactic of surgical treatment of complicated of Crohn's disease in children based on local intestinal resections with intestinal stomas. 4. It is very important to use a combined approach combining conservative and surgical treatment. Surgical treatment and drug treatment of Crohn's disease should be complementary treatments.
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Affiliation(s)
- O Gorbatyuk
- 1 Shupyk National Medical Academy of Postgraduate Education, Kyiv, Ukraine
| | - D Soleiko
- 2Pirogov Vinnitsa National Medical University, Ukraine
| | - H Kurylo
- 3Lviv City Children's Hospital, Ukraine
| | - N Soleiko
- 2Pirogov Vinnitsa National Medical University, Ukraine
| | - V Novak
- 2Pirogov Vinnitsa National Medical University, Ukraine
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Galindo-Mendez B, Trevino JA, McGlinchey R, Fortier C, Lioutas V, Novak P, Mantzoros CS, Ngo L, Novak V. Memory advancement by intranasal insulin in type 2 diabetes (MemAID) randomized controlled clinical trial: Design, methods and rationale. Contemp Clin Trials 2020; 89:105934. [PMID: 31923471 PMCID: PMC7242142 DOI: 10.1016/j.cct.2020.105934] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [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: 08/20/2019] [Revised: 12/06/2019] [Accepted: 01/03/2020] [Indexed: 01/21/2023]
Abstract
BACKGROUND Type 2 diabetes mellitus (T2DM) accelerates brain aging and increases the risk for dementia. Insulin is a key neurotrophic factor in the brain, where it modulates energy metabolism, neurovascular coupling, and regeneration. Impaired insulin-mediated brain signaling and central insulin resistance may contribute to cognitive and functional decline in T2DM. Intranasal insulin (INI) has emerged as a potential therapy for treating T2DM-related cognitive impairment. METHODS/DESIGN Ongoing from 2015, a prospective, two-center, randomized, double-blind, placebo-controlled trial of 210 subjects (120 T2DM and 90 non-diabetic older adults) randomized into four treatment arms (60 T2DM-INI, 60 T2DM-Placebo, 45 Control-INI, and 45 Control-Placebo) evaluating the long-term effects of daily intranasal administration of 40 International Units (IU) of human insulin, as compared to placebo (sterile saline) over 24 weeks and 24 weeks of post-treatment follow-up. Study outcomes are: 1) long-term INI effects on cognition, daily functionality, and gait speed; 2) identifying a clinically relevant phenotype that predicts response to INI therapy; 3) long-term safety. CONCLUSION This study addresses an important knowledge gap about the long-term effects of intranasal insulin on memory and cognition in older people with T2DM and non-diabetic controls, and may provide a novel therapeutic target for prevention and treatment of cognitive and functional decline and dementia. Trial Registration NCT02415556.
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Affiliation(s)
- B Galindo-Mendez
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - J A Trevino
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - R McGlinchey
- Translational Research Center for TBI and Stress Disorders (TRACTS), Geriatric Research Education and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - C Fortier
- Translational Research Center for TBI and Stress Disorders (TRACTS), Geriatric Research Education and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - V Lioutas
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - P Novak
- Autonomic Laboratory, Department of Neurology, Brigham and Women's Faulkner Hospital, Harvard Medical School, Boston, MA, USA
| | - C S Mantzoros
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston MA; Department of Medicine, Boston VA Healthcare System, Harvard Medical School, Boston, MA
| | - L Ngo
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - V Novak
- Department of Neurology, SAFE Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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Novak V, Adler J, Husted S, Fromberg A, Laursen KH. Authenticity testing of organically grown vegetables by stable isotope ratio analysis of oxygen in plant-derived sulphate. Food Chem 2019; 291:59-67. [DOI: 10.1016/j.foodchem.2019.03.125] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 03/21/2019] [Accepted: 03/24/2019] [Indexed: 02/01/2023]
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Shurko N, Danysh T, Novak V. PB2450 DYE-LIGAND CHROMATOGRAPHY AS AN ALTERNATIVE METHOD FOR OBTAINING THE FACTORS VIII/VON WILLEBRAND COMPLEX. Hemasphere 2019. [DOI: 10.1097/01.hs9.0000568260.29107.2f] [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: 11/25/2022] Open
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Hampl M, Kachlik D, Kikalova K, Riemer R, Halaj M, Novak V, Stejskal P, Vaverka M, Hrabalek L, Krahulik D, Nanka O. Mastoid foramen, mastoid emissary vein and clinical implications in neurosurgery. Acta Neurochir (Wien) 2018; 160:1473-1482. [PMID: 29779186 DOI: 10.1007/s00701-018-3564-2] [Citation(s) in RCA: 14] [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: 03/22/2018] [Accepted: 05/09/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND Mastoid emissary vein is especially important from the neurosurgical point of view, because it is located in variable number in the area of the occipitomastoid suture and it can become a source of significant bleeding in surgical approaches through the mastoid process, especially in retrosigmoid craniotomy, which is used for approaches to pathologies localized in the cerebellopontine angle. Ideal imaging method for diagnosis of these neglected structures when planning a surgical approach is high-resolution computed tomography. The aim of this work was to provide detailed information about this issue. METHODS We studied a group of 295 skulls obtained from collections of five anatomy departments and the National Museum. Both quantitative and qualitative parameters of the mastoid foramen were evaluated depending on side of appearance and gender. Individual distances of the mastoid foramen from clearly defined surface landmarks (asterion, apex of mastoid process, foramen magnum) and other anatomical structures closely related to this issue (width of groove for sigmoid sinus, diameters of internal and external openings of mastoid foramen) were statistically processed. RESULTS The most frequently represented type of the mastoid foramen is type II by Louis (41.2%). The differences between right and left sides were not statistically significant. In men there was a higher number of openings on the right side and in qualitative parameters the type III and IV predominated, whereas in women the types I and II were more frequent. In men, greater distances from the mastoid foramen were observed when evaluating qualitative parameters for defined surface landmarks. Mean size of the external opening diameter was 1.3 mm; however, several openings measured up to 7 mm. CONCLUSIONS Despite excellent knowledge of anatomy, however, good pre-operative examination using imaging methods and mastering of microsurgical techniques create the base for successful treatment of pathological structures in these anatomically complex areas.
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Affiliation(s)
- Martin Hampl
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - David Kachlik
- Department of Anatomy, Second Faculty of Medicine, Charles University, U nemocnice 3, Praha 2, 12800, Prague, Czech Republic.
| | - Katerina Kikalova
- Department of Anatomy, Faculty of Medicine and Dentistry, Palacky University Olomouc, Olomouc, Czech Republic
| | - Roxane Riemer
- Department of Anatomy, Second Faculty of Medicine, Charles University, U nemocnice 3, Praha 2, 12800, Prague, Czech Republic
| | - Matej Halaj
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Vlastimil Novak
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Premysl Stejskal
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Miroslav Vaverka
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Lumir Hrabalek
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - David Krahulik
- Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Ondrej Nanka
- Department of Anatomy, Second Faculty of Medicine, Charles University, U nemocnice 3, Praha 2, 12800, Prague, Czech Republic
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic
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17
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Novak V, Sadowski D, Shin S, Schoonover K, Abdel-Khalik SI. Experimental and Numerical Investigation of Mist Cooling for the Electra Hibachi. Fusion Science and Technology 2017. [DOI: 10.13182/fst05-a753] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- V. Novak
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405 USA
| | - D. Sadowski
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405 USA
| | - S. Shin
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405 USA
| | - K. Schoonover
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405 USA
| | - S. I. Abdel-Khalik
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405 USA
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Novak V, Abdel-Khalik SI, Sadowski DL, Schoonover KG. Investigation of Mist Cooling for the Electra KrF Laser Hibachi. Fusion Science and Technology 2017. [DOI: 10.13182/fst07-a1535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- V. Novak
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, GA 30332-0405 USA
| | - S. I. Abdel-Khalik
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, GA 30332-0405 USA
| | - D. L. Sadowski
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, GA 30332-0405 USA
| | - K. G. Schoonover
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, GA 30332-0405 USA
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Grzybowski MJ, Wadley P, Edmonds KW, Beardsley R, Hills V, Campion RP, Gallagher BL, Chauhan JS, Novak V, Jungwirth T, Maccherozzi F, Dhesi SS. Imaging Current-Induced Switching of Antiferromagnetic Domains in CuMnAs. Phys Rev Lett 2017; 118:057701. [PMID: 28211721 DOI: 10.1103/physrevlett.118.057701] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Indexed: 05/22/2023]
Abstract
The magnetic order in antiferromagnetic materials is hard to control with external magnetic fields. Using x-ray magnetic linear dichroism microscopy, we show that staggered effective fields generated by electrical current can induce modification of the antiferromagnetic domain structure in microdevices fabricated from a tetragonal CuMnAs thin film. A clear correlation between the average domain orientation and the anisotropy of the electrical resistance is demonstrated, with both showing reproducible switching in response to orthogonally applied current pulses. However, the behavior is inhomogeneous at the submicron level, highlighting the complex nature of the switching process in multidomain antiferromagnetic films.
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Affiliation(s)
- M J Grzybowski
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
- Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw, Poland
| | - P Wadley
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - K W Edmonds
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - R Beardsley
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - V Hills
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - R P Campion
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - B L Gallagher
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - J S Chauhan
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - V Novak
- Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, 162 00 Praha 6, Czech Republic
| | - T Jungwirth
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
- Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, 162 00 Praha 6, Czech Republic
| | - F Maccherozzi
- Diamond Light Source, Chilton, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - S S Dhesi
- Diamond Light Source, Chilton, Didcot, Oxfordshire OX11 0DE, United Kingdom
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Payne RME, Xu D, Foureau E, Teto Carqueijeiro MIS, Oudin A, de Bernonville TD, Novak V, Burow M, Olsen CE, Jones DM, Tatsis EC, Pendle A, Halkier BA, Geu-Flores F, Courdavault V, Nour-Eldin HH, O’Connor SE. An NPF transporter exports a central monoterpene indole alkaloid intermediate from the vacuole. Nat Plants 2017; 3:16208. [PMID: 28085153 PMCID: PMC5238941 DOI: 10.1038/nplants.2016.208] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 11/29/2016] [Indexed: 05/17/2023]
Abstract
Plants sequester intermediates of metabolic pathways into different cellular compartments, but the mechanisms by which these molecules are transported remain poorly understood. Monoterpene indole alkaloids, a class of specialized metabolites that includes the anticancer agent vincristine, antimalarial quinine and neurotoxin strychnine, are synthesized in several different cellular locations. However, the transporters that control the movement of these biosynthetic intermediates within cellular compartments have not been discovered. Here we present the discovery of a tonoplast localized nitrate/peptide family (NPF) transporter from Catharanthus roseus, CrNPF2.9, that exports strictosidine, the central intermediate of this pathway, into the cytosol from the vacuole. This discovery highlights the role that intracellular localization plays in specialized metabolism, and sets the stage for understanding and controlling the central branch point of this pharmacologically important group of compounds.
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Affiliation(s)
- Richard M. E. Payne
- The John Innes Centre, Department of Biological Chemistry, Norwich Research Park, Norwich NR4 7UK, UK
| | - Deyang Xu
- DynaMo Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Emilien Foureau
- Université François-Rabelais de Tours, EA2106 Biomolécules et Biotechnologies Végétales, Département de Biologie et Physiologie Végétales, UFR Sciences et Techniques, Parc de Grandmont 37200 Tours, France
| | - Marta Ines Soares Teto Carqueijeiro
- Université François-Rabelais de Tours, EA2106 Biomolécules et Biotechnologies Végétales, Département de Biologie et Physiologie Végétales, UFR Sciences et Techniques, Parc de Grandmont 37200 Tours, France
| | - Audrey Oudin
- Université François-Rabelais de Tours, EA2106 Biomolécules et Biotechnologies Végétales, Département de Biologie et Physiologie Végétales, UFR Sciences et Techniques, Parc de Grandmont 37200 Tours, France
| | - Thomas Dugé de Bernonville
- Université François-Rabelais de Tours, EA2106 Biomolécules et Biotechnologies Végétales, Département de Biologie et Physiologie Végétales, UFR Sciences et Techniques, Parc de Grandmont 37200 Tours, France
| | - Vlastimil Novak
- DynaMo Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Meike Burow
- DynaMo Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Carl-Erik Olsen
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - D. Marc Jones
- The John Innes Centre, Department of Computational and Systems Biology, Norwich Research Park, Norwich NR4 7UK, UK
| | - Evangelos C. Tatsis
- The John Innes Centre, Department of Biological Chemistry, Norwich Research Park, Norwich NR4 7UK, UK
| | - Ali Pendle
- The John Innes Centre, Department of Cell and Developmental Biology, Norwich Research Park, Norwich NR4 7UK, UK
| | - Barbara Ann Halkier
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Fernando Geu-Flores
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
- Section for Plant Biochemistry, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Vincent Courdavault
- Université François-Rabelais de Tours, EA2106 Biomolécules et Biotechnologies Végétales, Département de Biologie et Physiologie Végétales, UFR Sciences et Techniques, Parc de Grandmont 37200 Tours, France
| | - Hussam Hassan Nour-Eldin
- DynaMo Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Sarah E. O’Connor
- The John Innes Centre, Department of Biological Chemistry, Norwich Research Park, Norwich NR4 7UK, UK
- To whom correspondence should be addressed: Sarah E. O’Connor ()
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Novak V, Stojanović N, Stefanović I, Kostić A, Berilažić L. Expansive Processes of the Brain. J Neurol Surg A Cent Eur Neurosurg 2015. [DOI: 10.1055/s-0035-1566420] [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: 10/22/2022]
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Hrabalek L, Kalita O, Vaverka M, Zlevorova M, Ehrmann J, Cechakova E, Adamus M, Novak V, Langova K. Resection versus biopsy of glioblastomas in eloquent brain areas. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2015; 159:150-5. [DOI: 10.5507/bp.2013.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 07/01/2013] [Indexed: 11/23/2022] Open
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Wadley P, Crespi A, Gázquez J, Roldán M, García P, Novak V, Campion R, Jungwirth T, Rinaldi C, Martí X, Holy V, Frontera C, Rius J. Obtaining the structure factors for an epitaxial film using Cu X-ray radiation. J Appl Crystallogr 2013. [DOI: 10.1107/s002188981302414x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Determining atomic positions in thin films by X-ray diffraction is, at present, a task reserved for synchrotron facilities. Here an experimental method is presented which enables the determination of the structure factor amplitudes of thin films using laboratory-based equipment (Cu Kα radiation). This method was tested using an epitaxial 130 nm film of CuMnAs grown on top of a GaAs substrate, which unlike the orthorhombic bulk phase forms a crystal structure with tetragonal symmetry. From the set of structure factor moduli obtained by applying this method, the solution and refinement of the crystal structure of the film has been possible. The results are supported by consistent high-resolution scanning transmission electron microscopy and stoichiometry analyses.
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Hu K, Lo M, Liu Y, Peng C, Novak V. Nonlinear profile of cerebral autoregulation dynamics— Effects of stroke. Auton Neurosci 2011. [DOI: 10.1016/j.autneu.2011.05.166] [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: 10/18/2022]
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Wunderlich J, Park BG, Irvine AC, Zarbo LP, Rozkotova E, Nemec P, Novak V, Sinova J, Jungwirth T. Spin Hall Effect Transistor. Science 2010; 330:1801-4. [DOI: 10.1126/science.1195816] [Citation(s) in RCA: 257] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Manor B, Hu K, Zhao P, Selim M, Alsop D, Novak P, Lipsitz L, Novak V. Altered control of postural sway following cerebral infarction: a cross-sectional analysis. Neurology 2010; 74:458-64. [PMID: 20142612 DOI: 10.1212/wnl.0b013e3181cef647] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Balance impairment is common following cerebral infarction. However, the effects of lesion hemisphere on postural control are largely unknown. We examined dependence upon vision and noninfarcted regional brain tissue volumes for postural control in individuals with right and left hemisphere middle cerebral artery (MCA) infarcts. METHODS Subjects with right MCA infarct (n = 17, age = 65 +/- 8 years, 7 +/- 6 years poststroke), left MCA infarct (n = 20, age = 65 +/- 8 years, 7 +/- 6 years poststroke), and controls (n = 55, age = 65 +/- 8 years) were studied. Postural control was defined by average velocity and the range and variability of mediolateral (ML) and anteroposterior (AP) sway during eyes-open and eyes-closed standing. Regional brain volumes were quantified using anatomic MRI at 3 Tesla. RESULTS Right and left hemisphere stroke groups had similar infarct volumes and outcomes. Subjects with right hemisphere infarcts demonstrated greater sway velocity, ML range, and ML variability with eyes closed compared to eyes open. In this group, smaller occipital lobe volumes were associated with greater eyes-open sway velocity (R = -0.64, p = 0.012) and ML range (R = -0.82, p = 0.001). Smaller cerebellar volumes were associated with greater eyes-closed sway velocity (R = -0.60, p = 0.015), ML range (R = -0.70, p = 0.007), and ML variability (R = -0.85, p < 0.001). These associations were not observed in left hemisphere infarct subjects or controls. AP sway was unaffected by infarct hemisphere or visual condition and did not correlate with regional brain volumes. CONCLUSIONS Right hemisphere middle cerebral artery infarcts are associated with increased dependence on vision and noninfarcted brain regions (i.e., occipital lobes, cerebellum) to control postural sway. Strategies emphasizing postural tasks under reduced visual conditions may enhance functional recovery in these individuals.
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Affiliation(s)
- B Manor
- Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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Manor B, Costa M, Hu K, Peng C, Novak V, Lipsitz L. 179 EFFECTS OF SENSORY DETERIORATION ON BALANCE CONTROL IN OLDER ADULTS: CAUSES AND CONSEQUENCES OF COMPLEXITY LOSS. Parkinsonism Relat Disord 2010. [DOI: 10.1016/s1353-8020(10)70180-2] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Klecka J, Pesta M, Hora M, Kulda V, Holubec L, Topolcan O, Eret V, Babjuk M, Novak V, Stolz J. UP-1.125: Importance of miRNAs Expression in Prostate Cancer and Benign Prostate Tissue. Urology 2009. [DOI: 10.1016/j.urology.2009.07.572] [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: 10/20/2022]
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Neumann J, Novak V. SIMULATION OF SOME DYNAMIC PROPERTIES OF SARCOMERE INSIDE THE CARDIOMYOCYTE. BIOMED ENG-BIOMED TE 2009. [DOI: 10.1515/bmte.2000.45.s1.395] [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: 11/15/2022]
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Kostic A, Mihailovic D, Veselinovic S, Tasic D, Stefanovic I, Novak V, Stojanovic N, Veselinovic D, Pavlovic S. Tumor size and karyometric variables in brain astrocytoma. J BUON 2009; 14:473-477. [PMID: 19810141] [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] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
PURPOSE To show any possible correlation of some karyometric variables with tumor size in patients with brain astrocytoma, in order to confirm karyometry as an objective histological method. PATIENTS AND METHODS The study included 63 patients of different ages and both genders with brain astrocytoma histologically confirmed on the surgically removed material. In all patients maximal tumor excision was done, and all were postoperatively treated according to different therapeutic protocols. Tumor size (preoperative CT scan) was correlated with the duration of survival and the values of some karyometric tumor variables: area, density, maximal axis, mean axis, minimal axis, circumference, roundness, integrated optical density (IOD) and number of nuclei. RESULTS Patients were separated into 3 groups according to the average tumor diameter. There were 34 cases of medium-sized tumors, 12 of small and 17 of large-sized tumors, and their respective survival was 83, 97 and 24 weeks. Patients with large tumors had statistically shorter survival compared to those with medium and small tumors (log-rank test, p=0.0122). Seven out of 9 examined karyometric variables were significantly related (p<0.05) to the tumor size: area, maximal axis, mean axis, minimal axis, circumference, roundness and IOD. CONCLUSION Patients with larger tumors have shorter survival. The results of our morphometric analysis of the tumor cell nuclei, after correlation with CT findings, revealed that nuclear pleomorphism and larger nuclear size are associated with larger brain astrocytomas.
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Affiliation(s)
- A Kostic
- Clinic of Neurosurgery, Clinical Centre Nis, Serbia.
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Abstract
OBJECTIVE It is unknown if impaired cerebral vasoreactivity recovers after ischemic stroke, and whether it compromises perfusion in regions surrounding infarct and other vascular territories. We investigated the regional differences in CO2 vasoreactivity (CO2 VR) and their relationships to peri-infarct T2 hyperintensities (PIHs), chronic infarct volumes, and clinical outcomes. METHODS We studied 39 subjects with chronic large middle cerebral artery territory infarcts and 48 matched controls. Anatomic and three-dimensional continuous arterial spin labeling imaging at 3-Tesla MRI were used to measure regional cerebral blood flow (CBF) and CO2 VR during normocapnia, hypercapnia, and hypocapnia in main arteries distributions. RESULTS Stroke patients showed a significantly lower augmentation of blood flow at increased CO2 but greater reduction of blood flow with decreased CO2 than the control group. This altered vasoregulatory response was observed both ipsilateral and contralateral to the stroke. Lower CO2 VR on the stroke side was associated with PIHs, greater infarct volume, and worse outcomes. The cases with PIHs (n = 27) had lower CBF during all conditions bilaterally (p < 0.0001) compared to cases with infarct only. CONCLUSIONS Perfusion augmentation is inadequate in multiple vascular territories in patients with large artery ischemic infarcts, but vasoconstriction is preserved. Peri-infarct T2 hyperintensities are associated with lower blood flow. Strategies aimed to preserve vasoreactivity after an ischemic stroke should be tested for their effect on long-term outcomes.
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Affiliation(s)
- P Zhao
- Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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Novak V, Sadowski D, Schoonover K, Shin S, Abdel-Khalik S, Ghiaasiaan S. Heat transfer in two-component internal mist cooling. Nuclear Engineering and Design 2008. [DOI: 10.1016/j.nucengdes.2008.03.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Novak V, Sadowski D, Schoonover K, Abdel-Khalik S, Ghiaasiaan S. Heat transfer in two-component internal mist cooling. Nuclear Engineering and Design 2008. [DOI: 10.1016/j.nucengdes.2008.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Sourek Z, Kopecky M, Kub J, Busetto E, Lausi A, Cukr M, Novak V, Olejnik K. Location of Mn sites in GaMnAs thin films studied by means of X-ray diffuse scattering. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308082160] [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: 11/10/2022] Open
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Sittner P, Lugovyy D, Neov D, Landa M, Lukas P, Novak V. On the R-phase transformation related phenomena in NiTi polycrystals subjected to thermomechanical loads. ACTA ACUST UNITED AC 2004. [DOI: 10.1051/jp4:2004115032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
BACKGROUND Autoregulation of blood flow that maintains steady perfusion over the range of systemic blood pressure is compromised by stroke. OBJECTIVES To determine whether cerebral vasoregulation is impaired in stroke during orthostatic stress. METHODS Subjects included 30 control subjects, 30 with hypertension, and 20 with minor stroke and were studied using transcranial Doppler. Bilateral blood flow velocities (BFVs) from middle cerebral arteries, heart rate, blood pressure (BP), and CO2 were obtained during hyperventilation and CO2 rebreathing during supine rest and tilt at 80 degrees. Side-to-side BFV difference, vasomotor range (VMR), and cerebrovascular resistance (CVR) were calculated during normo-, hypo-, and hypercapnia. RESULTS Mean BFVs were similar between groups in supine position but differed during tilt. BFV diminished on the stroke side during tilt with hyperventilation and CO2 rebreathing (p < 0.0001). CVR increased (p < 0.0001) and VMR decreased (p < 0.01) on the stroke side. Vasoregulation was preserved on the normal side. BFV asymmetry differentiated patients with stroke from the other groups (p < 0.0001). BFV difference between the normal vs stroke side was the largest in stroke-normotensive (n = 7) compared with stroke-hypertensive (n = 13) patients and the two other groups (p < 0.0001). BFV asymmetry in stroke was associated with lower orthostatic BP (p < 0.0001). CONCLUSIONS Cerebral vasoregulation is impaired with minor stroke, and cerebral blood flow depends on blood pressure. Decline of blood flow velocities during orthostatic stress may pose a risk of silent hypoperfusion.
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Affiliation(s)
- V Novak
- Division of Gerontology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
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Abstract
To evaluate the effect of tiagabine hydrochloride in painful neuropathy in a pilot, open-label study. Painful neuropathy is characterized by preferential involvement of small sensory and autonomic fibers. Tiagabine increases gamma-aminobutyric acid and might enhance the central pain-control mechanisms. Seventeen patients (10 men, 7 women; mean age 51.4 +/- 7.7 y) with chronic painful neuropathy (>6 months) were enrolled in this study. Week 0: All pain medications were discontinued. Weeks 1-4: Dose of tiagabine was increased weekly by 4 mg orally up to 16 mg in week 4. Quantitative sensory testing for vibration, cooling, and heat-pain, and quantitative sudomotor axon reflex test (QSART) were done at week 0 and week 4. The McGill Pain Questionnaire was administered weekly. Nine patients completed the study; 8 patients discontinued the treatment. Baseline pain intensity was 6.2 +/- 3.1 on the McGill Pain Questionnaire scale (0-10 range). Low doses (4-8 mg) of tiagabine reduced pain symptoms by 16-38%, improving surface pain (37.5%), skin sensitivity (32.8%), burning (38.6%), cold (25.4%) and pain sharpness (29%; p <0.03). Dull and deep pain did not improve. Quantitative sensory testing abnormalities diminished with treatment (p <0.02). Autonomic test results did not change. This pilot study evaluated the potential of tiagabine hydrochloride (Gabitril) in treatment of painful sensory neuropathy. Pain symptoms and quantitative sensory test results improved with treatment, especially at low doses of tiagabine (4-8 mg). Higher doses (12-16 mg) were associated with increased number of adverse events. Tiagabine may have potential benefits for treatment of painful neuropathy; however, assessment of its efficacy in a larger study is needed.
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Affiliation(s)
- V Novak
- Department of Neurology, The Ohio State University, Columbus, USA.
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Sittner P, Lukas P, Daymond MR, Novak V, Swallowe GM. Stress induced martensitic transformation in CuAlZnMn polycrystals investigated by in situ neutron diffraction. ACTA ACUST UNITED AC 2001. [DOI: 10.1051/jp4:2001828] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Novak V, Abduljalil A, Kangarlu A, Slivka A, Bourekas E, Novak P, Chakeres D, Robitaille PM. Intracranial ossifications and microangiopathy at 8 Tesla MRI. Magn Reson Imaging 2001; 19:1133-7. [PMID: 11711239 DOI: 10.1016/s0730-725x(01)00447-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [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: 10/17/2022]
Abstract
UNLABELLED Clinical evaluation and MR imaging of microangiopathy associated with hypertension is limited. We describe a case that illustrates sensitivity of MRI at 8 Tesla for imaging of microvasculature, iron, calcium deposits and silent white matter lesions (WML). A 60-year-old black hypertensive woman was evaluated for numbness in the face and extremities. MRI at 1.5 Tesla was unrevealing.MRI at 8 Tesla: Axial and sagittal Gradient Echo images were obtained with an 8T/80 cm human scanner and showed: 1) Large areas of signal voids due to ossifications and fat deposits within the falx. 2) Obstructed small vessels in the periventricular regions and distended cortical veins. 3) Numerous small WML, suggestive of mini-infarcts (<1 cm) and microhemorrhages. 4) Intracranial calcifications in the falx, tentorium, basal ganglia and chorioid plexus that were confirmed by CT scan. Atherosclerotic plaque in right carotid artery and reduced vasomotor reserve in middle cerebral arteries, documented by ultrasound, indicated large and small vessel disease. CONCLUSIONS MRI at 8 Tesla improves visualization of microangiopathy, ossifications and iron deposits due to enhanced magnetic susceptibility at ultra high magnetic field.
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Affiliation(s)
- V Novak
- Department of Neurology, The Ohio State University, Columbus, Ohio 43210, USA.
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Novak V. New Ritalin ad blitz makes parents jumpy. Time 2001; 158:62-3. [PMID: 11558351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Abstract
PURPOSE Optimal treatment strategies and neurologic outcome after stroke depend on an accurate characterization of the lesion. There is a need for high resolution noninvasive imaging for assessment of the infarct size, perfusion, and vascular territory. MRI at the ultra high field (UHF) of 8 T offers unprecedented resolution, but its utility for stroke evaluation has not been determined yet. METHOD A 55-year-old man with hypertension experienced sudden onset of speech arrest and right-sided hemiparesis that resolved in < 24 h with minimal neurologic deficit. MRI at 1.5 T showed initially a left posterior frontal lesion with subacute infarct (hyperintense on T2-weighted spin echo images) and right-sided frontal and periventricular lesions consistent with chronic infarct. There were many smaller white matter lesions. Delayed studies showed high signal changes involving the gray matter only on T1-weighted images. RESULTS Gradient echo and rapid acquisition with relaxation enhancement (RARE) multislice images revealed a serpentine area of low signal in the left posterior frontal lobe gray matter suggestive of a hemorrhagic infarct, right-sided frontal lesion also showing iron deposits, multiple periventricular and cortical areas with abnormal high signal regions that were consistent with old infarcts, and numerous small vessels readily visible, more prominent on the right. CONCLUSION MRI at 8 T displays lesions with a high resolution and striking anatomic details. Susceptibility to iron and sensitivity to detect blood products are increased at 8 T. The imaging characteristics at high field are different from those at low field, but both represent findings of iron products.
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Affiliation(s)
- V Novak
- Department of Neurology, Ohio State University, Columbus 43210, USA.
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Abstract
OBJECTIVES 1) To determine the degree and distribution and quantitate the severity of autonomic impairment in painful neuropathy (PN). 2) To assess the role of autonomic testing in evaluating PN. METHODS The authors studied 92 patients with PN (60 women and 32 men, age 56.9 +/- 12.4 years) using: 1) autonomic reflex testing (ART), Quantitative Sudomotor Axon Reflex Test (QSART), cardiac-vagal, head-up tilt, and surface skin temperature; 2) autonomic symptoms questionnaire; 3) nerve conduction (NCS) and laboratory studies; 4) quantitative sensory testing; 5) skin biopsy; and 6) Composite Autonomic Symptoms Score (CASS) scale to grade ART results from 0 (normal) to 10 (autonomic failure). RESULTS Autonomic involvement in PN had characteristic features. Main symptoms were pain, secretory and skin vasomotor signs, hypertension, and impotence. ART results were abnormal in 86 (93.5%) (CASS < 4), QSART in 67 (72.8%), cardiac-vagal index in 58 (63%), skin temperature in 51 (55.4%), orthostatic hypertension in 39 (42.3%), and family history of PN in 26 (21%) of patients. Group 1 (abnormal NCS) (n = 45) had more severe ART and sensory abnormalities than the Group 2 (normal NCS) (n = 47): 1) CASS 2.0 +/- 0.96 vs 1.55 +/- 0.88 (p < 0.01), cardiac-vagal index (p < 0.02), skin temperature (p < 0.02), hypertension (p < 0.03), cooling (p < 0.002), and vibration (p < 0.0005) thresholds. CONCLUSIONS Autonomic symptoms in painful neuropathy are predominantly cholinergic and form a unique constellation of features that are distinct from other autonomic neuropathies.
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Affiliation(s)
- V Novak
- Department of Neurology, The Ohio State University, Columbus, OH 43210, USA.
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Abstract
A recently developed ultra high field MRI system operating at 8 T (UHFMRI) was applied for brainstem imaging. UHFMRI was performed in five healthy volunteers (three men, two women; age range 34--46 years). Sagittal and axial slices were obtained with the following settings: GE, TR 750--1,000 ms, TE 7-9 ms, FOV 20 cm, matrix 1,024 x 1,024 or 512 x 512 points, slice thickness 2 mm, resolution 195 or 390 microm/pixel. The brainstem structures were assigned based on anatomy and course. Images with good signal strength and homogeneity were acquired from the midbrain and the pons. Main intraaxial structures could be directly visualized. The periaqueductal gray matter and nuclei had higher signal intensity than the predominantly white matter structures such as the corticobulbar/corticopontine/corticospinal tracts, the sensory lemnisci, and the medial longitudinal fasciculus. Structures with high iron content such as the substantia nigra and the red nucleus were seen as prominent signal hypointensities. Numerous vessels traversing the brainstem including small perforators were also distinguished. It is concluded that UHFMRI enables the acquisition of high quality images of the upper brainstem with details approaching that of histologic specimen.
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Affiliation(s)
- P Novak
- Department of Neurology, Ohio State University, Columbus, OH 43210, USA
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Novak V. Abortion on trial, again. Time 2000; 155:38. [PMID: 11765507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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Gordon VM, Opfer-Gehrking TL, Novak V, Low PA. Hemodynamic and symptomatic effects of acute interventions on tilt in patients with postural tachycardia syndrome. Clin Auton Res 2000; 10:29-33. [PMID: 10750641 DOI: 10.1007/bf02291387] [Citation(s) in RCA: 54] [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] [Indexed: 10/25/2022]
Abstract
A variety of approaches have been used to alleviate symptoms in postural tachycardia syndrome (POTS). Drugs reported to be of benefit include midodrine, propranolol, clonidine, and phenobarbital. Other measures used include volume expansion and physical countermaneuvers. These treatments may influence pathophysiologic mechanisms of POTS such as alpha-receptor dysfunction, beta-receptor supersensitivity, venous pooling, and brainstem center dysfunction. The authors prospectively studied hemodynamic indices and symptom scores in patients with POTS who were acutely treated with a variety of interventions. Twenty-one subjects who met the criteria for POTS were studied (20 women, 1 man; mean age, 28.7 +/- 6.8 y; age range, 14-39 y). Patients were studied with a 5-minute head-up tilt protocol, ECG monitoring, and noninvasive beat-to-beat blood pressure monitoring, all before and after the administration of an intervention (intravenous saline, midodrine, propranolol, clonidine, or phenobarbital). The hemodynamic indices studied were heart rate (ECG) and systolic, mean, and diastolic blood pressure. Patients used a balanced verbal scale to record any change in their symptoms between the tilts. Symptom scores improved significantly after the patients received midodrine and saline. Midodrine and propranolol reduced the resting heart rate response to tilt (p <0.005) and the immediate and 5-minute heart rate responses to tilt (p <0.002). Clonidine accentuated the immediate decrease in blood pressure on tilt up (p <0.05). It was concluded that midodrine and intravenous saline are effective in decreasing symptoms on tilt in patients with POTS when given acutely. Effects of treatments on heart rate and blood pressure responses generally reflected the known pharmacologic mechanisms of the agents.
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Affiliation(s)
- V M Gordon
- Autonomic Disorders Center, Rochester, Minnesota, USA
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Sandroni P, Novak V, Opfer-Gehrking TL, Huck CA, Low PA. Mechanisms of blood pressure alterations in response to the Valsalva maneuver in postural tachycardia syndrome. Clin Auton Res 2000; 10:1-5. [PMID: 10750636 DOI: 10.1007/bf02291382] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [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: 10/25/2022]
Abstract
The postural tachycardia syndrome (POTS) is characterized clinically by orthostatic lightheadedness and tachycardia. When these patients perform a Valsalva maneuver, there is an excessive blood pressure increment after cessation of the maneuver (phase IV) that is sometimes associated with headaches. It is not known whether excessive phase IV is due to excessive peripheral vascular tone (an alpha-adrenergic mechanism) or is a manifestation of increased beta-adrenergic tone (hyperadrenergic state). The authors undertook a pharmacologic study evaluating the effect of intravenous phentolamine (alpha-adrenergic antagonist) and propranolol (beta-adrenergic antagonist) on the different phases of the Valsalva maneuver in a group of patients with POTS and age-matched normal control subjects. Patients with POTS had mean phases, when compared with controls, that were characterized by more negative II_E (p = 0.07), smaller II_L (p = 0.04), and significantly larger phase IV (p = 0.001). The effect of phentolamine was qualitatively and quantitatively different in POTS when compared with controls. Ten mg phentolamine in controls resulted in a significant accentuation of phase II_E (p = 0.001), attenuation of phase II_L (p = 0.002), and increase of phase IV (57.6 vs 30.7 mm Hg; p = 0.025). These changes resembled those of patients with POTS at baseline. In patients with POTS, the phase II abnormalities, already present, were further accentuated (p <0.001), and phase IV became smaller (50.6 vs 73.8 mm Hg; p = 0.09). Propranolol had no significant effect on phases II_E and II_L, but significantly reduced phase IV in both controls (p <0.05) and in patients with POTS (p <0.001) and improved the headache symptoms, when present, during and after phase IV. The authors conclude that phase IV is mainly under beta-adrenergic regulation and that the exaggerated phase IV in POTS is a result of a hyperadrenergic state.
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Affiliation(s)
- P Sandroni
- Department of Neurology, Mayo Clinic, Rochester, Minnesota 55905, USA
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Novak V. The Claritin case: how one firm played the patent game. Time 1999; 154:42. [PMID: 10622840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Periquet MI, Novak V, Collins MP, Nagaraja HN, Erdem S, Nash SM, Freimer ML, Sahenk Z, Kissel JT, Mendell JR. Painful sensory neuropathy: prospective evaluation using skin biopsy. Neurology 1999; 53:1641-7. [PMID: 10563606 DOI: 10.1212/wnl.53.8.1641] [Citation(s) in RCA: 248] [Impact Index Per Article: 9.9] [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: 11/15/2022] Open
Abstract
OBJECTIVE In patients presenting with painful, burning feet with minimal signs of neuropathy, the following questions were addressed: 1) How many of these patients have a peripheral neuropathy? 2) What is the role of skin biopsy in establishing a diagnosis of neuropathy? 3) What conditions are associated with the neuropathy? and 4) What laboratory studies are useful in this patient population? METHODS A total of 117 consecutive patients referred for evaluation were prospectively studied. All underwent nerve conduction studies (NCS) and a battery of blood tests, including antinerve antibodies. If NCS were normal, a punch biopsy of the skin of the distal leg was performed to ascertain the intraepidermal nerve fiber (IENF) density. In a subset of 32 patients, the sensitivity of skin biopsy was compared to quantitative sudomotor axon test (QSART) and quantitative sensory tests (QST). RESULTS Three groups emerged. Group 1, with abnormal NCS (n = 60, 34 F/26 M, mean age 60 +/- 14 years), represented 51% of the cohort. The majority had neuropathies of undetermined cause, but 18 (30%) had associated conditions. Group 2, with normal NCS and reduced IENF density (n = 44, 29 F/15 M, mean age 57 +/- 14 years), represented 38% of the cohort. Three in this group had associated conditions. Group 3, with normal NCS and IENF density (n = 13, 6 F/7 M, mean age 53 +/- 13 years), represented 11% of the cohort; most had no diagnoses but two had MS. In a comparative subset analysis, skin biopsy was more sensitive than QSART or QST in diagnosing a neuropathy. CONCLUSIONS Patients presenting with painful feet are heterogeneous, consisting of both large and small fiber sensory neuropathies. In rare cases, a central cause for pain can be found. Over one-third of patients required a skin biopsy to diagnose a small fiber sensory neuropathy. A limited battery of blood tests facilitated diagnosis, but serum antinerve antibodies were not helpful.
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Affiliation(s)
- M I Periquet
- Department of Neurology, The Ohio State University, Columbus 43210, USA.
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Novak V, Reeves AL, Novak P, Low PA, Sharbrough FW. Time-frequency mapping of R-R interval during complex partial seizures of temporal lobe origin. J Auton Nerv Syst 1999; 77:195-202. [PMID: 10580303] [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] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND Activation of autonomic nervous system is common with seizures. No reliable biological markers of impending seizures have been found. Evaluation of autonomic changes might help elucidate the transition from interictal to ictal states. METHODS We studied twelve patients (eight females, four males), from 19 to 62 years old with temporal lobe complex partial seizures (CPS). Dynamics of autonomic functions from oscillations in R-R interval (RRI) using time-frequency mapping based upon a Wigner distribution during pre-ictal, ictal and post-ictal periods. Oscillations in RRI at respiratory frequencies (RF) (> 0.1 Hz) are parasympathetically mediated and at nonrespiratory frequencies (NONRF) (0.01-0.09 Hz) are under combined sympathetic and parasympathetic influence. RESULTS CPS evoked marked autonomic imbalance and tachycardia. Spectral powers at both RF_RRI and NONRF_RRI increased over the pre-ictal period. RF_RRI power then fell rapidly over the 30 s before seizure onset and remained markedly reduced during seizure (P < 0.004). NONRF_RRI power reached a maximum at seizure onset and declined to a minimum before the seizure cessation (P < 0.05). CONCLUSION Time-frequency analysis revealed that autonomic activation hallmarks clinical seizure onset for several minutes. After combined parasympathetic and sympathetic activation, rapid parasympathetic withdrawal occurred approximately 30 s before the seizure, and sympathetic activation peaks at seizure onset. Therefore, the transition from interictal to ictal states is relatively long and associated with subclinical autonomic changes.
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Affiliation(s)
- V Novak
- Department of Neurology, The Ohio State University, Columbus 43210, USA.
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