601
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Thakral NK, Mohapatra S, Stephenson GA, Suryanarayanan R. Compression-induced crystallization of amorphous indomethacin in tablets: characterization of spatial heterogeneity by two-dimensional X-ray diffractometry. Mol Pharm 2014; 12:253-63. [PMID: 25438193 DOI: 10.1021/mp5005788] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tablets of amorphous indomethacin were compressed at 10, 25, 50, or 100 MPa using either an unlubricated or a lubricated die and stored individually at 35 °C in sealed Mylar pouches. At selected time points, tablets were analyzed by two-dimensional X-ray diffractometry (2D-XRD), which enabled us to profile the extent of drug crystallization in tablets, in both the radial and axial directions. To evaluate the role of lubricant, magnesium stearate was used as "internal" and/or "external" lubricant. Indomethacin crystallization propensity increased as a function of compression pressure, with 100 MPa pressure causing crystallization immediately after compression (detected using synchrotron radiation). However, the drug crystallization was not uniform throughout the tablets. In unlubricated systems, pronounced crystallization at the radial surface could be attributed to die wall friction. The tablet core remained substantially amorphous, irrespective of the compression pressure. Lubrication of the die wall with magnesium stearate, as external lubricant, dramatically decreased drug crystallization at the radial surface. The spatial heterogeneity in drug crystallization, as a function of formulation composition and compression pressure, was systematically investigated. When formulating amorphous systems as tablets, the potential for compression induced crystallization warrants careful consideration. Very low levels of crystallization on the tablet surface, while profoundly affecting product performance (decrease in dissolution rate), may not be readily detected by conventional analytical techniques. Early detection of crystallization could be pivotal in the successful design of a dosage form where, in order to obtain the desired bioavailability, the drug may be in a high energy state. Specialized X-ray diffractometric techniques (2D; use of high intensity synchrotron radiation) enabled detection of very low levels of drug crystallization and revealed the heterogeneity in crystallization within the tablet.
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Affiliation(s)
- Naveen K Thakral
- Eli Lilly and Company , Lilly Corporate Center, Indianapolis, Indiana 46285, United States
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602
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Yasin I, Drga V, Plack CJ. Effect of human auditory efferent feedback on cochlear gain and compression. J Neurosci 2014; 34:15319-26. [PMID: 25392499 PMCID: PMC4228134 DOI: 10.1523/jneurosci.1043-14.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 09/10/2014] [Accepted: 09/13/2014] [Indexed: 11/21/2022] Open
Abstract
The mammalian auditory system includes a brainstem-mediated efferent pathway from the superior olivary complex by way of the medial olivocochlear system, which reduces the cochlear response to sound (Warr and Guinan, 1979; Liberman et al., 1996). The human medial olivocochlear response has an onset delay of between 25 and 40 ms and rise and decay constants in the region of 280 and 160 ms, respectively (Backus and Guinan, 2006). Physiological studies with nonhuman mammals indicate that onset and decay characteristics of efferent activation are dependent on the temporal and level characteristics of the auditory stimulus (Bacon and Smith, 1991; Guinan and Stankovic, 1996). This study uses a novel psychoacoustical masking technique using a precursor sound to obtain a measure of the efferent effect in humans. This technique avoids confounds currently associated with other psychoacoustical measures. Both temporal and level dependency of the efferent effect was measured, providing a comprehensive measure of the effect of human auditory efferents on cochlear gain and compression. Results indicate that a precursor (>20 dB SPL) induced efferent activation, resulting in a decrease in both maximum gain and maximum compression, with linearization of the compressive function for input sound levels between 50 and 70 dB SPL. Estimated gain decreased as precursor level increased, and increased as the silent interval between the precursor and combined masker-signal stimulus increased, consistent with a decay of the efferent effect. Human auditory efferent activation linearizes the cochlear response for mid-level sounds while reducing maximum gain.
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Affiliation(s)
- Ifat Yasin
- Ear Institute, University College London, London WC1X 8EE, United Kingdom, and
| | - Vit Drga
- Ear Institute, University College London, London WC1X 8EE, United Kingdom, and
| | - Christopher J Plack
- School of Psychological Sciences, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PL, United Kingdom
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603
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Abstract
UNLABELLED Based on the recommendations of experts, and supported by a low level of proof, compression after sclerotherapy is applied all over the world. OBJECTIVE Investigating the practice of French vascular physicians for sclerotherapy and the use of post-sclerotherapy compression. METHODS A questionnaire concerning their practices was sent to French vascular physicians through their regional vascular medicine professional development associations. RESULTS A total of 366 vascular physicians replied to the questionnaire, of whom 63% (229/366) were in private practice, 6% (21/366) in hospitals and 31% (115/366) had a mixed private-hospital practice. Sclerotherapy was practised by 88% (323/366) of them. Two-thirds of the vascular physicians used sclerosing foam and practised sclerotherapy using ultrasound guidance. Less than one-third of the vascular physicians regularly applied compression after sclerotherapy. When compression was applied, it was usually after treatment of saphenous or accessory saphenous veins and, in most cases, medical compression stockings of 15-20 mm Hg were used. With respect to the period recommended for wearing compression, this ranged from 48 h to 1 week for 65% (193/299) of the vascular physicians questioned. CONCLUSION The great majority of vascular physicians who answered the questionnaire employ ultrasound guidance to perform sclerotherapy and use sclerosing foam. Compression after sclerotherapy is diversely applied in France and does not comply with the recommendations of the French Health Authorities who recommend wearing a stocking of 15-20 or 20-36 mm Hg for a period of 4-6 weeks. Thus, less than one-third of the vascular physicians regularly used elastic compression and when they did, it was usually a medical compression stocking of 15-20 mm Hg, for 1 week or less.
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Affiliation(s)
- V Tripey
- Saint-Martin Private Hospital, Vascular Medicine, Caen, France
| | | | - R Morello
- Biostatistics Laboratory, University Hospital, Caen, France
| | - C Hamel-Desnos
- Saint-Martin Private Hospital, Vascular Medicine, Caen, France
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604
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Zhu F, Lai X, Wu X, Li Y, Qin S. Experimental and theoretical investigation on the compression mechanism of FeF3 up to 62.0 GPa. Acta Crystallogr B Struct Sci Cryst Eng Mater 2014; 70:801-8. [PMID: 25274513 DOI: 10.1107/s2052520614014322] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 06/18/2014] [Indexed: 11/10/2022]
Abstract
VF3-type FeF3 is generally considered as a perovskite with a completely vacant A site. The high-pressure structural evolution of FeF3 has been studied by both X-ray diffraction and theoretical simulation up to 62.0 GPa. Experimental and theoretical results demonstrate that VF3-type FeF3 is stable up to 50 GPa. The structural evolution presents three features at different pressure ranges. At P < 10 GPa, the volume reduction is dominated by the FeF6 octahedral rotation, and a small octahedral strain develops upon compression, which represents an elongation of FeF6 octahedra along the c axis. Between 10 and 25 GPa, the volume reduction is mainly attributed to the Fe-F bond length decreasing, and the octahedral strain gradually disappears. Between 25 and 50 GPa, an octahedral elongation along the a axis quickly develops, resulting in a substantial structural distortion. Structural instability is predicted at P > 51 GPa on the basis of a soft mode occurring in phonon calculations. The pressure-volume relationship is described by a third-order Birch-Murnaghan equation-of-state with B0 = 14 (1) GPa, B0' = 17 (1) by experiment and B0 = 10.45 (1) GPa, B'10 = 12.13 (1) by calculation.
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Affiliation(s)
- Feng Zhu
- Key Laboratory of Orogenic Belts and Crustal Evolution, MOE, Peking University, Beijing 100871, People's Republic of China
| | - Xiaojing Lai
- Key Laboratory of Orogenic Belts and Crustal Evolution, MOE, Peking University, Beijing 100871, People's Republic of China
| | - Xiang Wu
- Key Laboratory of Orogenic Belts and Crustal Evolution, MOE, Peking University, Beijing 100871, People's Republic of China
| | - Yanchun Li
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Shan Qin
- Key Laboratory of Orogenic Belts and Crustal Evolution, MOE, Peking University, Beijing 100871, People's Republic of China
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605
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Abstract
PURPOSE To report our results of canaliculitis treatment with our incision-sparing technique which includes dilation of the punctum and compression of the canaliculus to express the sulphur granules, curettage and irrigation of the canaliculus with antibiotic solutions, and topical antibiotic use. METHODS The medical records of all patients treated for canaliculitis between October 2009 and March 2013 were rewiewed. The punctum of affected canaliculus was dilated under local anesthesia. Then, starting just distal to common canaliculus, the horizontal canaliculus was compressed along its entire length using either a forceps or a cotton tip applicator on the conjunctival surface and a curette on the skin. Compression was repeated until no more sulphur granules appeared and the swelling of the canaliculus disappeared. A chalazion curette was inserted into canaliculus to evacuate any residual concretions. The canaliculus were irrigated with antibiotic solutions and the patients were prescribed topical antibiotic solutions for one month Patients with follow-up less than 3 months after the intervention were excluded from the study. RESULTS Nine patients met criteria for canaliculitis. There were 1 male and 8 female patients. Median age of the patients was 53 years (range 36-72 years). All patients had unilateral lower canaliculitis. Mean duration of the symptoms was 13.4 months (range 4-36 months). We followed up all patients for at least 3 months after the intervention. The signs and symptoms resolved completely in all patients within 1 month and recurrence was not observed in any patient. No patients reported epiphora after the procedure. CONCLUSION Our incision-sparing technique is effective in the treatment of canaliculitis. We suggest that minimally invasive or incision-sparing techniques be attempted before canaliculotomy to decrease postoperative complications rates.
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606
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Mitsuoka H, Ohta T, Hayashi S, Yokoi T, Arima T, Asamoto K, Nakano T. Histological study on the left common iliac vein spur. Ann Vasc Dis 2014; 7:261-5. [PMID: 25298827 DOI: 10.3400/avd.oa.14-00082] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 07/14/2014] [Indexed: 12/19/2022] Open
Abstract
The spur occasionally seen in a left common iliac vein was investigated by anatomical and histological examination of cadavers so the occurrence mechanism could be discussed. Spurs were found in six cases of the 28 cadavers (21.4%) and they were classified into few different kinds of composition of endosporia, tunica media and adventitia. It is considered that there may be different formation mechanisms and stages even in cases of similar anatomical finding. (English translation of J Jpn Coll Angiol 2013; 53: 43-47).
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Affiliation(s)
| | - Takashi Ohta
- Department of Surgery, Division of Vascular Surgery, Aichi Medical University, Nagakute, Aichi, Japan
| | - Shogo Hayashi
- Medical Education Center, Aichi Medical University, Nagakute, Aichi, Japan ; Department of Anatomy, Aichi Medical University, Nagakute, Aichi, Japan
| | - Toyoharu Yokoi
- Department of Diagnostic Pathology, Aichi Medical University Hospital, Nagakute, Aichi, Japan
| | - Takahiro Arima
- Student of Aichi Medical University, Nagakute, Aichi, Japan
| | - Ken Asamoto
- Department of Anatomy, Aichi Medical University, Nagakute, Aichi, Japan
| | - Takashi Nakano
- Department of Anatomy, Aichi Medical University, Nagakute, Aichi, Japan
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607
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Pandey P, Bindra DS, Gour S, Trinh J, Buckley D, Badawy S. Excipient-process interactions and their impact on tablet compaction and film coating. J Pharm Sci 2014; 103:3666-3674. [PMID: 25223603 DOI: 10.1002/jps.24169] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/21/2014] [Accepted: 08/29/2014] [Indexed: 11/08/2022]
Abstract
The objective of this study was to establish the effects of the level of minor formulation components (sodium lauryl sulfate: SLS, and magnesium stearate: MgSt) and manufacturing process on final blend compaction properties and the performance of the tablets during film coating. A 2 × 2 × 3 factorial study was conducted at two levels of SLS (0% and 1%, w/w) and MgSt (0.5% and 1.75%, w/w), along with three different manufacturing processes (direct compression, high-shear wet granulation, and dry granulation). The tablets were compressed to the same solid fraction (0.9) and the resulting tablet hardness values were found to vary over a range of 13-42 SCU, highlighting large compactability differences among these batches. Increase in the level of SLS or MgSt in the formulation had a significant negative effect on compactability and the performance of film-coated tablets. The detrimental effects on compaction and coating performance were magnified for the dry granulation process, likely due to the overall increased shear experienced by excipients (SLS, MgSt, microcrystalline cellulose) during the roller compaction and milling steps. The findings of this study highlight the importance of the manufacturing process when considering the use-level of formulation components such as SLS and MgSt in the formulation.
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Affiliation(s)
- Preetanshu Pandey
- Drug Product Science and Technology, Bristol-Myers Squibb1 Squibb Drive, New Brunswick, New Jersey 08901.
| | - Dilbir S Bindra
- Drug Product Science and Technology, Bristol-Myers Squibb1 Squibb Drive, New Brunswick, New Jersey 08901
| | - Shruti Gour
- Drug Product Science and Technology, Bristol-Myers Squibb1 Squibb Drive, New Brunswick, New Jersey 08901
| | - Jade Trinh
- Drug Product Science and Technology, Bristol-Myers Squibb1 Squibb Drive, New Brunswick, New Jersey 08901
| | - David Buckley
- Drug Product Science and Technology, Bristol-Myers Squibb1 Squibb Drive, New Brunswick, New Jersey 08901
| | - Sherif Badawy
- Drug Product Science and Technology, Bristol-Myers Squibb1 Squibb Drive, New Brunswick, New Jersey 08901
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608
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Kobayashi H, Horikawa K, Ogawa K, Watanabe K. Impact compressive and bending behaviour of rocks accompanied by electromagnetic phenomena. Philos Trans A Math Phys Eng Sci 2014; 372:20130292. [PMID: 25071241 DOI: 10.1098/rsta.2013.0292] [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] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
It is well known that electromagnetic phenomena are often observed preceding earthquakes. However, the mechanism by which these electromagnetic waves are generated during the fracture and deformation of rocks has not been fully identified. Therefore, in order to examine the relationship between the electromagnetic phenomena and the mechanical properties of rocks, uniaxial compression and three-point bending tests for two kinds of rocks with different quartz content, granite and gabbro, have been carried out at quasi-static and dynamic rates. Especially, in the bending tests, pre-cracked specimens of granite were also tested. Using a split Hopkinson pressure bar and a ferrite-core antenna in close proximity to the specimens, both the stress-strain (load-displacement) curve and simultaneous electromagnetic wave magnitude were measured. It was found that the dynamic compressive and bending strengths and the stress increase slope of both rocks were higher than those observed in static tests; therefore, there is a strain-rate dependence in their strength and stress increase rate. It was found from the tests using the pre-cracked bending specimens that the intensity of electromagnetic waves measured during crack extension increased almost proportionally to the increase of the maximum stress intensity factor of specimens. This tendency was observed in both the dynamic and quasi-static three-point bending tests for granite.
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Affiliation(s)
- Hidetoshi Kobayashi
- Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka 560-8531, Japan
| | - Keitaro Horikawa
- Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka 560-8531, Japan
| | - Kinya Ogawa
- Institute of Space Dynamics, 3-6 Ondoyamacho, Narutaki, Ukyo, Kyoto 616-8255, Japan
| | - Keiko Watanabe
- Department of Mechanical Engineering, College of Science and Engineering, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu 525-8577, Japan
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609
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Abstract
OBJECTIVE This article describes the typical imaging findings and clinical features that are associated with four abdominal vascular compression syndromes. We explain the underlying pathophysiology that results in these clinical syndromes so that the patient subset who will benefit from treatment can be identified. CONCLUSION The abdominal vascular compression syndromes discussed here are uncommon and are potentially easily missed on a cursory review of radiologic examinations, particularly in a nonspecific and vague clinical setting. Hence, knowledge of the typical imaging findings and associated clinical symptoms is essential so that the they can be carefully sought and excluded. However, because these findings may also exist in healthy individuals as anatomic variants, it is important to correlate radiologic findings with clinical symptoms to identify the subset of patients who will benefit from treatment.
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610
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Suehiro K, Honda S, Kakutani H, Morikage N, Murakami M, Yamashita O, Ueda K, Samura M, Hamano K. A novel arm sleeve for upper extremity lymphedema: a pilot study. Ann Vasc Dis 2014; 7:134-40. [PMID: 24995057 DOI: 10.3400/avd.oa.14-00013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 03/19/2014] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To investigate the safety and efficacy of a novel arm sleeve composed of a conventional arm sleeve extending to a wider area of the body. MATERIALS AND METHODS Five subjects with post-mastectomy upper extremity lymphedema, who had already been using their own arm sleeve, used a brand-new conventional arm sleeve for 2 weeks, followed by a novel arm sleeve for 2 weeks. The adverse events, arm-related symptoms, interface pressures, and subcutaneous fluid distributions observed by magnetic resonance imaging (MRI) were assessed. RESULTS The use of the novel arm sleeve resulted in a graduated compression extending to the shoulder (forearm, 21.8 ± 3.7 mmHg; upper arm, 15.2 ± 3.3 mmHg; shoulder, 8.8 ± 3.1 mmHg). By eliminating the wring seen in the conventional arm sleeve, the disturbed proximal diffusion of the subcutaneous fluid and venous occlusion were successfully avoided, as confirmed by MRI. No adverse event or worsening of arm-related symptoms was reported. CONCLUSION The novel arm sleeve seemed to provide graduated compression to a wider area, allowing improved subcutaneous fluid and venous drainage without any adverse events. Therefore, the novel arm sleeve may be recommended as a compression therapy option for upper extremity lymphedema.
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Affiliation(s)
- Kotaro Suehiro
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Saiko Honda
- Department of Nursing, Yamaguchi University Hospital, Ube, Yamaguchi, Japan
| | - Hiromi Kakutani
- Department of Nursing, Yamaguchi University Hospital, Ube, Yamaguchi, Japan
| | - Noriyasu Morikage
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Masanori Murakami
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Osamu Yamashita
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Koshiro Ueda
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Makoto Samura
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Kimikazu Hamano
- Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
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611
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Affiliation(s)
- Andrew R Hsu
- Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA
| | - Dawn Franceschina
- Advocate Lutheran General Hospital Wound Care Center, Park Ridge, IL, USA
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612
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Qian JG, Li Z, Zhang H, Bian R, Zhang S. Effectiveness of Selected Fitness Exercises on Stress of Femoral Neck using Musculoskeletal Dynamics Simulations and Finite Element Model. J Hum Kinet 2014; 41:59-70. [PMID: 25114732 DOI: 10.2478/hukin-2014-0033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The purpose of the study was to establish a dynamics model and a three-dimensional (3D) finite element model to analyze loading characteristics of femoral neck during walking, squat, single-leg standing, and forward and lateral lunges. One male volunteer performed three trials of the five movements. The 3D kinematic data were captured and imported into the LifeMOD to establish a musculoskeletal dynamics model to obtain joint reaction and muscle forces of iliacus, gluteus medius, gluteus maximus, psoas major and adductor magnus. The loading data LfeMOD were imported and transformed into a hip finite-element model. The results of the finite element femur model showed that stress was localized along the compression arc and the tension arc. In addition, the trabecular bone and tension lines of the Ward's triangle also demonstrated high stress. The compact bone received the greatest peak stress in the forward lunge and the least stress in the squat. However, the spongy bone in the femoral neck region had the greatest stress during the walk and the least stress in the squat. The results from this study indicate that the forward lunge may be an effective method to prevent femoral neck fractures. Walking is another effective and simple method that may improve bone mass of the Ward's triangle and prevent osteoporosis and femoral neck fracture.
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613
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McHenry CL, Wu J, Shields RK. Potential regenerative rehabilitation technology: implications of mechanical stimuli to tissue health. BMC Res Notes 2014; 7:334. [PMID: 24894666 PMCID: PMC4055276 DOI: 10.1186/1756-0500-7-334] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 05/21/2014] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Mechanical loads induced through muscle contraction, vibration, or compressive forces are thought to modulate tissue plasticity. With the emergence of regenerative medicine, there is a need to understand the optimal mechanical environment (vibration, load, or muscle force) that promotes cellular health. To our knowledge no mechanical system has been proposed to deliver these isolated mechanical stimuli in human tissue. We present the design, performance, and utilization of a new technology that may be used to study localized mechanical stimuli on human tissues. A servo-controlled vibration and limb loading system were developed and integrated into a single instrument to deliver vibration, compression, or muscle contractile loads to a single limb (tibia) in humans. The accuracy, repeatability, transmissibility, and safety of the mechanical delivery system were evaluated on eight individuals with spinal cord injury (SCI). FINDINGS The limb loading system was linear, repeatable, and accurate to less than 5, 1, and 1 percent of full scale, respectively, and transmissibility was excellent. The between session tests on individuals with spinal cord injury (SCI) showed high intra-class correlations (>0.9). CONCLUSIONS All tests supported that therapeutic loads can be delivered to a lower limb (tibia) in a safe, accurate, and measureable manner. Future collaborations between engineers and cellular physiologists will be important as research programs strive to determine the optimal mechanical environment for developing cells and tissues in humans.
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Affiliation(s)
- Colleen L McHenry
- Department of Physical Therapy & Rehabilitation Science, Carver College of Medicine, University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242-1190, USA
| | - Jason Wu
- Department of Physical Therapy & Rehabilitation Science, Carver College of Medicine, University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242-1190, USA
| | - Richard K Shields
- Department of Physical Therapy & Rehabilitation Science, Carver College of Medicine, University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242-1190, USA
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614
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Abstract
Healed or open venous ulcers may be present in up to 1% of Western populations and consume a large amount of healthcare resources. These ulcers are characterized by a chronic inflammatory environment with impaired healing and often require months for closure. The average monthly cost of care for an open ulcer has been estimated to be $4095. The fundamental tenets of ulcer care include adequate compression and maintaining a moist wound environment with an appropriate primary dressing. A number of specialized products including semi-occlusive/occlusive, antimicrobial, and advanced wound matrix dressings are now available. However, there is little data from appropriate clinical studies to suggest significantly improved outcomes with any of these dressings. Data regarding their cost-effectiveness is also limited, often conflicting, and subject to bias. At present, there is little solid evidence to guide the choice of primary dressings and a patient-centered approach focusing on characteristics of both the patient and their ulcer, while paying attention to costs, may be most appropriate.
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Affiliation(s)
- Mark H Meissner
- Department of Surgery, University of Washington, Seattle, Washington, USA
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615
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Nenezic D, Tanaskovic S, Gajin P, Ilijevski N, Novakovic A, Radak D. A rare case of large isolated internal iliac artery aneurysm with ureteral obstruction and hydronephrosis: Compression symptoms are limitation for endovascular procedures. Vascular 2014; 23:170-5. [PMID: 24821682 DOI: 10.1177/1708538114533963] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
INTRODUCTION In this report, we aim to present a rare case of isolated internal iliac artery aneurysm with associated left ureteric obstruction and consequent hydronephrosis. CASE REPORT A 66-year-old male patient was admitted for occasional pain in the lower back that appeared one month earlier. CT arteriography revealed isolated internal iliac artery (diameter 99 mm) with ureteral obstruction, hydroureter and left kidney hydronephrosis occurrence. Aneurysm was resected, after six months the patient was doing well. Bearing in mind that 77% of the patients with isolated internal iliac artery have symptoms caused by aneurysmal compression on adjacent organs, we wanted to highlight that despite the amazing expansion of endovascular procedures in the last decades, its therapeutic effect in isolated internal iliac artery's treatment is to a great extent limited since compression symptoms cannot be solved. CONCLUSION Open surgery remains the gold standard for isolated internal iliac artery's treatment considering significant limitations of endovascular procedures due to the inability to eliminate problems caused by compression.
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Affiliation(s)
- Dragoslav Nenezic
- Vascular Surgery Clinic, "Dedinje" Cardiovascular Institute, Serbia Faculty of Medicine, University of Belgrade, Serbia
| | | | - Predrag Gajin
- Vascular Surgery Clinic, "Dedinje" Cardiovascular Institute, Serbia Faculty of Medicine, University of Belgrade, Serbia
| | - Nenad Ilijevski
- Vascular Surgery Clinic, "Dedinje" Cardiovascular Institute, Serbia Faculty of Medicine, University of Belgrade, Serbia
| | | | - Djordje Radak
- Vascular Surgery Clinic, "Dedinje" Cardiovascular Institute, Serbia Faculty of Medicine, University of Belgrade, Serbia
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616
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Dixon AR, Moraes C, Csete ME, Thouless MD, Philbert MA, Takayama S. One-dimensional patterning of cells in silicone wells via compression-induced fracture. J Biomed Mater Res A 2014; 102:1361-9. [PMID: 23733484 PMCID: PMC3912204 DOI: 10.1002/jbm.a.34814] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 05/04/2013] [Accepted: 05/21/2013] [Indexed: 12/13/2022]
Abstract
We have adapted our existing compression-induced fracture technology to cell culture studies by generating linear patterns on a complex cell culture well structure rather than on simple solid constructs. We present a simple method to create one-dimensional (1D), submicron, and linear patterns of extracellular matrix on a multilayer silicone material. We identified critical design parameters necessary to optimize compression-induced fracture patterning on the wells, and applied stresses using compression Hoffman clamps. Finite-element analyses show that the incorporation of the well improves stress homogeneity (stress variation = 25%), and, thus, crack uniformity over the patterned region. Notably, a shallow well with a thick base (vs. deeper wells with thinner bases) reduces out-of-plane deflections by greater than a sixth in the cell culture region, improving clarity for optical imaging. The comparison of cellular and nuclear shape indices of a neuroblast line cultured on patterned 1D lines and unpatterned 2D surfaces reveals significant differences in cellular morphology, which could impact many cellular functions. Because 1D cell cultures recapitulate many important phenotypical traits of 3D cell cultures, our culture system offers a simple means to further study the relationship between 1D and 3D cell culture environments, without demanding expensive engineering techniques and expertise.
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Affiliation(s)
- Angela R. Dixon
- Toxicology Program, School of Public Health, University of Michigan, Ann Arbor, Michigan
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor Michigan
| | - Christopher Moraes
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor Michigan
| | - Marie E. Csete
- Departments of Anesthesiology and Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan (Current affiliation: AABB Center for Cellular Therapies, Bethesda, Maryland)
| | - M. D. Thouless
- Departments of Mechanical Engineering and Materials Science & Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
| | - Martin A. Philbert
- Toxicology Program, School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Shuichi Takayama
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor Michigan
- Macromolecular Science and Engineering Program, College of Engineering, University of Michigan, Ann Arbor, Michigan
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617
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Abstract
UNLABELLED It is becoming increasingly impractical to indefinitely store raw sequencing data for later processing in an uncompressed state. In this paper, we describe a scalable compressive framework, Read-Quality-Sparsifier (RQS), which substantially outperforms the compression ratio and speed of other de novo quality score compression methods while maintaining SNP-calling accuracy. Surprisingly, RQS also improves the SNP-calling accuracy on a gold-standard, real-life sequencing dataset (NA12878) using a k-mer density profile constructed from 77 other individuals from the 1000 Genomes Project. This improvement in downstream accuracy emerges from the observation that quality score values within NGS datasets are inherently encoded in the k-mer landscape of the genomic sequences. To our knowledge, RQS is the first scalable sequence based quality compression method that can efficiently compress quality scores of terabyte-sized and larger sequencing datasets. AVAILABILITY An implementation of our method, RQS, is available for download at: http://rqs.csail.mit.edu/.
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Affiliation(s)
- Y William Yu
- Massachusetts Institute of Technology, Cambridge MA 02139, USA http://people.csail.mit.edu/bab/
| | - Deniz Yorukoglu
- Massachusetts Institute of Technology, Cambridge MA 02139, USA http://people.csail.mit.edu/bab/
| | - Bonnie Berger
- Massachusetts Institute of Technology, Cambridge MA 02139, USA http://people.csail.mit.edu/bab/
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618
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de Godoy JMP, Facio FN, de Carvalho ECM, Godoy MDFG. New compression mechanism in penile-scrotal lymphedema and sexual rehabilitation. Urol Ann 2014; 6:88-90. [PMID: 24669133 PMCID: PMC3963354 DOI: 10.4103/0974-7796.127025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 10/11/2012] [Indexed: 11/04/2022] Open
Abstract
The objective of this study is to describe a new compression mechanism in the treatment of lymphedema of the penis and scrotum and the ensuing sexual rehabilitation. The patient, a 58-year-old man, had edema of the penile and scrotal region as a result of surgery of the pancreas and spleen and chemotherapy. The patient complained of pain, discomfort, and difficulties to walk and urinate. A clinical diagnosis of lymphedema of the penis and scrotum was reached. Treatment involved the continuous use of a cotton-polyester compression garment for the region together with thorough hygiene skin care. The swelling reduced significantly within a week to almost a normal aspect which was accompanied by clinical improvements of the symptoms. The reduction in penile edema allowed sexual rehabilitation even though erectile dysfunction required the use of a specific medication (sildenafil). In conclusion, simple and low-cost options can improve lymphedema of the penis and scrotum and allow sexual rehabilitation.
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Affiliation(s)
| | | | | | - Maria de Fatima Guerreiro Godoy
- Occupational Therapist, Professor of the Stricto-Sensu Post Graduation in Medicine School of São Jose do Rio Preto-FAMERP, researcher of Clínica Godoy, São Jose do Rio Preto-Brazil
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619
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Dewulf A, De Meulemeester T, Dehon M, Engel MS, Michez D. A new interpretation of the bee fossil Melitta willardi Cockerell (Hymenoptera, Melittidae) based on geometric morphometrics of the wing. Zookeys 2014:35-48. [PMID: 24715773 PMCID: PMC3974431 DOI: 10.3897/zookeys.389.7076] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Accepted: 02/27/2014] [Indexed: 11/12/2022] Open
Abstract
Although bees are one of the major lineages of pollinators and are today quite diverse, few well-preserved fossils are available from which to establish the tempo of their diversification/extinction since the Early Cretaceous. Here we present a reassessment of the taxonomic affinities of Melitta willardiCockerell 1909, preserved as a compression fossil from the Florissant shales of Colorado, USA. Based on geometric morphometric wing shape analyses M. willardi cannot be confidently assigned to the genus Melitta Kirby (Anthophila, Melittidae). Instead, the species exhibits phenotypic affinity with the subfamily Andreninae (Anthophila, Andrenidae), but does not appear to belong to any of the known genera therein. Accordingly, we describe a new genus, Andrenopteryxgen. n., based on wing shape as well as additional morphological features and to accommodate M. willardi. The new combination Andrenopteryx willardi (Cockerell) is established.
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Affiliation(s)
- Alexandre Dewulf
- University of Mons, Research Institute of Biosciences, Laboratory of Zoology, Place du parc 20, 7000 Mons, Belgium
| | - Thibaut De Meulemeester
- University of Mons, Research Institute of Biosciences, Laboratory of Zoology, Place du parc 20, 7000 Mons, Belgium ; Naturalis Biodiversity Center, Darwinweg 2, PoBox 9517, 2300RA Leiden, the Netherlands
| | - Manuel Dehon
- University of Mons, Research Institute of Biosciences, Laboratory of Zoology, Place du parc 20, 7000 Mons, Belgium
| | - Michael S Engel
- Division of Entomology (Paleoentomology), Natural History Museum, and Department of Ecology and Evolutionary Biology, 1501 Crestline Drive - Suite 140, University of Kansas, Lawrence, KS 66045, U.S.A
| | - Denis Michez
- University of Mons, Research Institute of Biosciences, Laboratory of Zoology, Place du parc 20, 7000 Mons, Belgium
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620
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Abstract
OBJECTIVES Reactive hyperaemia following thigh compression increases arterial inflow and venous outflow. The net effect can be measured by changes in calf volume quantified using air-plethysmography. The objective was to investigate the effect of thigh compression on venous return. METHOD The right legs of 19 consecutive volunteers (14 male), median age 31 (25-56) years, were studied in the supine position using air-plethysmography. The clinical, etiological, anatomical, pathophysiological (CEAP) class was C0. A thigh-cuff, 12 cm wide, was inflated in increments of 10 mmHg, from 0 to 80 mmHg. After each inflation step, the calf volume increased to a plateau and was recorded. At 80 mmHg, the thigh-cuff was deflated suddenly with the calf volume decreasing until baseline. Calf volume changes were recorded and stored for analysis. RESULTS There was a stepwise increase in the venous volume of the calf with each incremental rise in thigh-cuff pressure up to 80 mmHg (p < .0005, Friedman). The median (interquartile range) increase in venous volume from 0 to 80 mmHg was 87 (65-113) mL (p < .0005, Wilcoxon). The volume change below the original baseline following thigh-cuff release was -16 (-12 to -25) mL (p < .0005, Wilcoxon). CONCLUSIONS Once optimised, intermittent pneumatic compression of the thigh may have a therapeutic role in augmenting the venous return and reducing leg swelling in patients.
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Affiliation(s)
- Christopher R Lattimer
- Josef Pflug Vascular Laboratory, Ealing and Northwick Park Hospitals and Imperial College, London, UK
| | - Evi Kalodiki
- Josef Pflug Vascular Laboratory, Ealing and Northwick Park Hospitals and Imperial College, London, UK
| | - Mustapha Azzam
- Josef Pflug Vascular Laboratory, Ealing and Northwick Park Hospitals and Imperial College, London, UK
| | - George Geroulakos
- Josef Pflug Vascular Laboratory, Ealing and Northwick Park Hospitals and Imperial College, London, UK
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621
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Tseng KK, He X, Kung WM, Chen ST, Liao M, Huang HN. Wavelet-based watermarking and compression for ECG signals with verification evaluation. Sensors (Basel) 2014; 14:3721-36. [PMID: 24566636 PMCID: PMC3958288 DOI: 10.3390/s140203721] [Citation(s) in RCA: 20] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 02/06/2014] [Accepted: 02/18/2014] [Indexed: 02/05/2023]
Abstract
In the current open society and with the growth of human rights, people are more and more concerned about the privacy of their information and other important data. This study makes use of electrocardiography (ECG) data in order to protect individual information. An ECG signal can not only be used to analyze disease, but also to provide crucial biometric information for identification and authentication. In this study, we propose a new idea of integrating electrocardiogram watermarking and compression approach, which has never been researched before. ECG watermarking can ensure the confidentiality and reliability of a user's data while reducing the amount of data. In the evaluation, we apply the embedding capacity, bit error rate (BER), signal-to-noise ratio (SNR), compression ratio (CR), and compressed-signal to noise ratio (CNR) methods to assess the proposed algorithm. After comprehensive evaluation the final results show that our algorithm is robust and feasible.
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Affiliation(s)
- Kuo-Kun Tseng
- Department of Computer Science and Technology, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen 518055, China.
| | - Xialong He
- Department of Computer Science and Technology, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen 518055, China.
| | - Woon-Man Kung
- Department of Exercise and Health Promotion, College of Education, Chinese Culture University (CCU) and Department of Neurosurgery, Lo-Hsu Foundation, Lotung Poh-Ai Hospital, Luodong, Yilan 265, Taiwan.
| | - Shuo-Tsung Chen
- Department of Applied Mathematics, Tunghai University, Taichung 40704, Taiwan.
| | - Minghong Liao
- Department of Software Engineering, Xiamen University, Xiamen 361005, China.
| | - Huang-Nan Huang
- Department of Applied Mathematics, Tunghai University, Taichung 40704, Taiwan.
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622
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Onur TS, Wu R, Chu S, Chang W, Kim HT, Dang ABC. Joint instability and cartilage compression in a mouse model of posttraumatic osteoarthritis. J Orthop Res 2014; 32:318-23. [PMID: 24167068 PMCID: PMC4462343 DOI: 10.1002/jor.22509] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [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: 06/19/2013] [Accepted: 10/03/2013] [Indexed: 02/04/2023]
Abstract
Joint instability and cartilage trauma have been previously studied and identified as key mediators in the development of posttraumatic osteoarthritis (PTOA). The purpose of this study was to use an in vivo model to compare the effect of joint instability, caused by the rupture of the anterior cruciate ligament (ACL), versus cartilage compression. In this study, mice were subjected to cyclical axial loads of twelve Newtons (N) for 240 cycles or until the ACL ruptured. One and eight weeks after this procedure, knees were sectioned coronally and evaluated for osteoarthritis by histology. Using a scoring scale established by [Pritzker K, Gay S, Jimenez S, et al. (2006): Osteoarthritis Cartilage 14:13-29], the articular cartilage across each surface was scored and combined to produce a total degeneration score. The ACL-ruptured group had a significantly greater total degeneration score than either control or compression treated joints at 1 and 8 weeks. Additionally, only sections from ACL-ruptured knees consistently showed synovitis after 1 week and osteophyte formation after 8 weeks. Thus, it appears using that ACL rupture consistently creates a severe osteoarthritis phenotype, while axial cartilage compression alone does not appear to be an appropriate method of inducing PTOA in vivo.
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Affiliation(s)
- Tarik S. Onur
- San Francisco Veterans Affairs Medical Center; Department of Orthopaedic Surgery
| | - Ruobin Wu
- San Francisco Veterans Affairs Medical Center; Department of Orthopaedic Surgery
| | - Stacey Chu
- San Francisco Veterans Affairs Medical Center; Department of Orthopaedic Surgery
| | - Wenhan Chang
- San Francisco Veterans Affairs Medical Center; Department of Endocrinology,University of California, San Francisco; Department of Endocrinology
| | - Hubert T. Kim
- San Francisco Veterans Affairs Medical Center; Department of Orthopaedic Surgery,University of California, San Francisco; Department of Orthopaedic Surgery
| | - Alexis BC Dang
- San Francisco Veterans Affairs Medical Center; Department of Orthopaedic Surgery,University of California, San Francisco; Department of Orthopaedic Surgery
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623
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El-Refaeey AA, Gibreel A, Fawzy M. Novel modification of B-Lynch uterine compression sutures for management of atonic postpartum hemorrhage: VV uterine compression sutures. J Obstet Gynaecol Res 2014; 40:387-91. [PMID: 24118407 DOI: 10.1111/jog.12166] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/23/2013] [Indexed: 11/29/2022]
Abstract
AIM The aim of this study was to demonstrate a novel modification of uterine compression sutures for use in women with primary postpartum hemorrhage and to evaluate its effectiveness. MATERIAL AND METHODS This was a prospective observational study. Nineteen patients with atonic postpartum hemorrhage were subjected to the novel VV uterine compression sutures at the time of cesarean delivery. RESULTS The procedure was successful in 18 out of 19 women (94.7%) in controlling the bleeding and preserving the patient's uterus. Only one patient required supravaginal hysterectomy. CONCLUSIONS VV compression sutures comprise an easy, safe and effective procedure that can be applied in cases of atonic postpartum hemorrhage.
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Affiliation(s)
- Abdel-Aziz El-Refaeey
- Department of Obstetrics and Gynecology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
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624
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Raijada D, Müllertz A, Cornett C, Munk T, Sonnergaard J, Rantanen J. Miniaturized approach for excipient selection during the development of oral solid dosage form. J Pharm Sci 2014; 103:900-8. [PMID: 24436033 DOI: 10.1002/jps.23840] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 12/09/2013] [Accepted: 12/10/2013] [Indexed: 01/10/2023]
Abstract
The present study introduces a miniaturized high-throughput platform to understand the influence of excipients on the performance of oral solid dosage forms during early drug development. Wet massing of binary mixtures of the model drug (sodium naproxen) and representative excipients was followed by sieving, drying, and compaction of the agglomerated material. The mini-compacts were subjected to stability studies at 25°C/5% relative humidity (RH), 25°C/60% RH and 40°C/75% RH for 3 months. The physical stability of the drug was affected by the storage condition and by the characteristics of the excipients, whereas all the samples were chemically stable. Force-distance curves obtained during the compression of agglomerated material were used for the comparison of compressibility of different drug-excipient mixtures. The agglomerated drug-excipient mixtures were also subjected to studies of the dissolution trend under sequential pH conditions to simulate pH environment of gastrointestinal tract. Major factors affecting the dissolution behavior were the diffusion layer pH of the binary mixtures and the ability of the excipients to alter the diffusion layer thickness. The proposed approach can be used for excipient selection and for early-stage performance testing of active pharmaceutical ingredient intended for oral solid dosage form.
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Affiliation(s)
- Dhara Raijada
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2100, Denmark
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625
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Bloechlinger S, Nebiker M, Windecker S. Unusual cause of myocardial infarction and congestive heart failure in a patient with prosthetic valve endocarditis. Catheter Cardiovasc Interv 2014; 83:E69-72. [PMID: 23723097 DOI: 10.1002/ccd.25033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 04/03/2013] [Revised: 05/01/2013] [Accepted: 05/19/2013] [Indexed: 11/08/2022]
Abstract
In a patient with staphylococcus lugdunensis prosthetic aortic valve endocarditis and coronary septic embolism accompanied by antero-lateral myocardial infarction, embolic material was successfully aspirated from the bifurcation of the left anterior descending coronary artery and the first diagonal branch. A good angiographic result was documented six months thereafter when the patient presented with a second complication, pulsatile compression of the left main coronary artery by an abscess cavity originating between the aortic and mitral annulus, leading to congestive heart failure. The patient underwent successful surgical replacement of the aortic valve prosthesis with concomitant patch reconstruction of the annulus as well as tricuspid annuloplasty.
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Affiliation(s)
- Stefan Bloechlinger
- Department of Cardiology, Inselspital, University Hospital Bern & University of Bern, Bern, Switzerland; Department of Intensive Care Medicine, Inselspital, University Hospital Bern & University of Bern, Bern, Switzerland
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626
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Rosales-Velderrain A, Padilla M, Choe CH, Hargens AR. Increased microvascular flow and foot sensation with mild continuous external compression. Physiol Rep 2013; 1:e00157. [PMID: 24744851 PMCID: PMC3970751 DOI: 10.1002/phy2.157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 09/24/2013] [Accepted: 09/27/2013] [Indexed: 11/29/2022] Open
Abstract
Intermittent pneumatic compression of the calf and foot increases inflow to the popliteal artery and skin. We hypothesize that mild, continuous pneumatic compression of the lower extremities of type 2 diabetic patients increases microvascular blood flow to skin (SBF) and muscle (MBF) and improves sensation in feet. Data were collected on 19 healthy volunteers and 16 type 2 diabetic patients. Baseline values of SBF, MBF, and foot sensation were recorded in one leg. The lower extremity was then subjected to 30 mmHg of continuous external air pressure for 30 min, whereas SBF and MBF were continuously monitored. Sensation was reassessed after pressure was released. During 30 mmHg continuous external compression, the healthy control group significantly increased MBF by 39.8% (P < 0.01). Sensation of the foot in this group improved significantly by 49.8% (P < 0.01). In the diabetic group, there was a significant increase in MBF of 17.7% (P = 0.03). Also sensation improved statistically by 40.2% (P = 0.03). Importantly and counterintuitively, MBF and foot sensation both increase after 30 min of leg compression at 30 mmHg. Therefore, mild, continuous pneumatic compression may be a new approach for treating diabetic patients with compromised leg perfusion and sensation. Leg blood flow and foot sensation after external compression.
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Affiliation(s)
| | - Michael Padilla
- Department of Orthopaedic Surgery, University of California San Diego, San Diego, California
| | - Charles H Choe
- Department of Orthopaedic Surgery, University of California San Diego, San Diego, California
| | - Alan R Hargens
- Department of Orthopaedic Surgery, University of California San Diego, San Diego, California
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627
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Abstract
The exponential growth of high-throughput DNA sequence data has posed great challenges to genomic data storage, retrieval and transmission. Compression is a critical tool to address these challenges, where many methods have been developed to reduce the storage size of the genomes and sequencing data (reads, quality scores and metadata). However, genomic data are being generated faster than they could be meaningfully analyzed, leaving a large scope for developing novel compression algorithms that could directly facilitate data analysis beyond data transfer and storage. In this article, we categorize and provide a comprehensive review of the existing compression methods specialized for genomic data and present experimental results on compression ratio, memory usage, time for compression and decompression. We further present the remaining challenges and potential directions for future research.
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628
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Aoki S, Uchiyama J, Ito M. Development of new shaped punch to predict scale-up issue in tableting process. J Pharm Sci 2013; 103:235-40. [PMID: 24218176 DOI: 10.1002/jps.23781] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 10/02/2013] [Accepted: 10/16/2013] [Indexed: 11/06/2022]
Abstract
Scale-up issues in the tableting process, such as capping, sticking, or differences in tablet thickness, are often observed at the commercial production scale. A new shaped punch, named the size adjusted for scale-up (SAS) punch, was created to estimate scale-up issues seen between laboratory scale and commercial scale tableting processes. The SAS punch's head shape was designed to replicate the total compression time of a laboratory tableting machine to that of a commercial tableting machine. Three different lubricated blends were compressed into tablets using a laboratory tableting machine equipped with SAS punches, and any differences in tablet thickness or capping phenomenon were observed. It was found that the new shaped punch could be used to replicate scale-up issues observed in the commercial tableting machine. The SAS punch was shown to be a useful tool to estimate scale-up issues in the tableting process.
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Affiliation(s)
- Shigeru Aoki
- Global Demand Chain Technology Japan, New Chemical Entity, Eisai Demand Chain Systems, Eisai Company Ltd., Kakamigahara-Shi, Gifu, 501-6195, Japan
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629
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Abstract
Most hearing aid prescriptions focus on the optimization of a metric derived from the long-term average spectrum of speech, and do not consider how the prescribed values might distort the temporal envelope shape. A growing body of evidence suggests that such distortions can lead to systematic errors in speech perception, and therefore hearing aid prescriptions might benefit by including preservation of the temporal envelope shape in their rationale. To begin to explore this possibility, we designed a genetic algorithm (GA) to find the multiband compression settings that preserve the shape of the original temporal envelope while placing that envelope in the listener's audiometric dynamic range. The resulting prescription had a low compression threshold, short attack and release times, and a combination of compression ratio and gain that placed the output signal within the listener's audiometric dynamic range. Initial behavioral tests of individuals with impaired hearing revealed no difference in speech-in-noise perception between the GA and the NAL-NL2 prescription. However, gap detection performance was superior with the GA in comparison to NAL-NL2. Overall, this work is a proof of concept that consideration of temporal envelope distortions can be incorporated into hearing aid prescriptions.
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Affiliation(s)
- Andrew T Sabin
- 1Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
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630
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Iyer R, Hegde S, Zhang YE, Dinunzio J, Singhal D, Malick A, Amidon G. The impact of hot melt extrusion and spray drying on mechanical properties and tableting indices of materials used in pharmaceutical development. J Pharm Sci 2013; 102:3604-13. [PMID: 23955277 DOI: 10.1002/jps.23661] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 06/04/2013] [Accepted: 06/17/2013] [Indexed: 11/11/2022]
Abstract
The impact of melt extrusion (HME) and spray drying (SD) on mechanical properties of hypromellose acetate succinate (HPMCAS), copovidone, and their formulated blends was studied and compared with that of reference excipients. Tensile strength (TS), compression pressure (CP), elastic modulus (E), and dynamic hardness (Hd ) were determined along with Hiestand indices using compacts prepared at a solid fraction of ∼0.85. HPMCAS and copovidone exhibited lower Hd , lower CP, and lower E than the reference excipients and moderate TS. HPMCAS was found to be highly brittle based on brittle fracture index values. The CP was 24% and 61% higher for HPMCAS after SD and HME, respectively, than for unprocessed material along with a higher Hd . Furthermore, the TS of HPMCAS and copovidone decreased upon HME. Upon blending melt-extruded HPMCAS with plastic materials such as microcrystalline cellulose, the TS increased. These results suggest that SD and HME could impact reworkability by reducing deformation of materials and in case of HME, likely by increasing density due to heating and shear stress in a screw extruder. A somewhat similar effect was observed for the dynamic binding index (BId ) of the excipients and formulated blends. Such data can be used to quantitate the impact of processing on mechanical properties of materials during tablet formulation development.
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Affiliation(s)
- Raman Iyer
- Pharmaceutical & Analytical R & D, Hoffmann-La Roche Inc, Nutley, New Jersey, 07110
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631
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Katz JM, Roopwani R, Buckner IS. A material-sparing method for assessment of powder deformation characteristics using data collected during a single compression-decompression cycle. J Pharm Sci 2013; 102:3687-93. [PMID: 23897398 DOI: 10.1002/jps.23676] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 05/26/2013] [Accepted: 07/03/2013] [Indexed: 11/09/2022]
Abstract
Compressibility profiles, or functions of solid fraction versus applied pressure, are used to provide insight into the fundamental mechanical behavior of powders during compaction. These functions, collected during compression (in-die) or post ejection (out-of-die), indicate the amount of pressure that a given powder formulation requires to be compressed to a given density or thickness. To take advantage of the benefits offered by both methods, the data collected in-die during a single compression-decompression cycle will be used to generate the equivalent of a complete out-of-die compressibility profile that has been corrected for both elastic and viscoelastic recovery of the powder. This method has been found to be both a precise and accurate means of evaluating out-of-die compressibility for four common tableting excipients. Using this method, a comprehensive characterization of powder compaction behavior, specifically in relation to plastic/brittle, elastic and viscoelastic deformation, can be obtained. Not only is the method computationally simple, but it is also material-sparing. The ability to characterize powder compressibility using this approach can improve productivity and streamline tablet development studies.
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Affiliation(s)
- Jeffrey M Katz
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, 15282
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632
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Kaminski TW, Hertel J, Amendola N, Docherty CL, Dolan MG, Hopkins JT, Nussbaum E, Poppy W, Richie D. National Athletic Trainers' Association position statement: conservative management and prevention of ankle sprains in athletes. J Athl Train 2013; 48:528-45. [PMID: 23855363 PMCID: PMC3718356 DOI: 10.4085/1062-6050-48.4.02] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To present recommendations for athletic trainers and other allied health care professionals in the conservative management and prevention of ankle sprains in athletes. BACKGROUND Because ankle sprains are a common and often disabling injury in athletes, athletic trainers and other sports health care professionals must be able to implement the most current and evidence-supported treatment strategies to ensure safe and rapid return to play. Equally important is initiating preventive measures to mitigate both first-time sprains and the chance of reinjury. Therefore, considerations for appropriate preventive measures (including taping and bracing), initial assessment, both short- and long-term management strategies, return-to-play guidelines, and recommendations for syndesmotic ankle sprains and chronic ankle instability are presented. RECOMMENDATIONS The recommendations included in this position statement are intended to provide athletic trainers and other sports health care professionals with guidelines and criteria to deliver the best health care possible for the prevention and management of ankle sprains. An endorsement as to best practice is made whenever evidence supporting the recommendation is available.
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Affiliation(s)
- Thomas W Kaminski
- National Athletic Trainers’ Association, Communications Department, 2952 Stemmons Freeway, Dallas, TX 75247, USA
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633
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Garry H, McGinley B, Jones E, Glavin M. An evaluation of the effects of wavelet coefficient quantisation in transform based EEG compression. Comput Biol Med 2013; 43:661-9. [PMID: 23668341 PMCID: PMC4754580 DOI: 10.1016/j.compbiomed.2013.02.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 02/11/2013] [Accepted: 02/14/2013] [Indexed: 11/25/2022]
Abstract
In recent years, there has been a growing interest in the compression of electroencephalographic (EEG) signals for telemedical and ambulatory EEG applications. Data compression is an important factor in these applications as a means of reducing the amount of data required for transmission. Allowing for a carefully controlled level of loss in the compression method can provide significant gains in data compression. Quantisation is easy to implement method of data reduction that requires little power expenditure. However, it is a relatively simple, non-invertible operation, and reducing the bit-level too far can result in the loss of too much information to reproduce the original signal to an appropriate fidelity. Other lossy compression methods allow for finer control over compression parameters, generally relying on discarding signal components the coder deems insignificant. SPIHT is a state of the art signal compression method based on the Discrete Wavelet Transform (DWT), originally designed for images but highly regarded as a general means of data compression. This paper compares the approaches of compression by changing the quantisation level of the DWT coefficients in SPIHT, with the standard thresholding method used in SPIHT, to evaluate the effects of each on EEG signals. The combination of increasing quantisation and the use of SPIHT as an entropy encoder has been shown to provide significantly improved results over using the standard SPIHT algorithm alone.
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Affiliation(s)
- Higgins Garry
- College of Engineering and Informatics, New Engineering Building, National University of Ireland, Galway, Galway, Ireland.
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634
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Larson EJ, Guggenheimer JD. The effects of scaling tennis equipment on the forehand groundstroke performance of children. J Sports Sci Med 2013; 12:323-331. [PMID: 24149812 PMCID: PMC3761839] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 01/10/2013] [Indexed: 06/02/2023]
Abstract
The modifications that have taken place within youth sports have made games, such as basketball, soccer, or tennis, easier for children to play. The purpose of this study was to determine the effects low compression (LC) tennis balls and scaled tennis courts had on the forehand groundstroke performance of children. The forehand groundstroke performances of eight subjects' (8.10 ± 0.74 yrs) using LC tennis balls were measured on a scaled tennis court and standard compression balls (SC) on a standard court. Forehand groundstroke performance was assessed by the ForeGround test which measures Velocity Precision Success Index (VPS) and Velocity Precision Index (VP). Participants attempted three different forehand rally patterns on two successive days, using LC balls on the 18.3m court one day and SC balls on the 23.8m court the other. When using LC balls, participants' recorded higher overall VPS performance scores (p < 0.001) for each non-error stroke as well as higher VP scores (p = 0.01). The results of this study confirmed that the use of modified balls and modified court size may increase the control, velocity and overall success rate of the tennis forehand groundstroke of children. Key PointsThis study observed the effects of modified tennis balls and court had on the forehand groundstroke performance in children.Modified ball compression and modified court size can increase control, velocity and overall success of tennis performance.Children will have more success learning the game of tennis using modified equipment than using standard equipment.
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Affiliation(s)
- Emma J Larson
- Choice Health and Fitness, Tennis Professional, Grand Forks, ND, USA
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635
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Abstract
Tendons are designed to absorb and transfer large amounts of tensile load. The well organised, strong yet flexible, extracellular matrix allows for this function. Many tendons are also subject to compressive loads, such as at the entheses, as the tendon wraps around bony protuberances or from internal compression during tensile loading or twisting. Tendinopathy, the clinical syndrome of pain and dysfunction in a tendon is usually the result of overload. However, it is not only the tensile overload that should be considered, as it has been shown that compressive loads change tendon structure and that combination loads can induce tendon pathology. This review summarises how load is detected by the tenocytes, how they respond to compressive load and the resulting extracellular matrix changes that occur. Understanding the effect of compression on tendon structure and function may provide directions for future matrix based interventions.
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Affiliation(s)
- Sean Docking
- School of Primary Health Care, Monash University, Peninsula Campus, Frankston, Australia
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636
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Marouane H, Shirazi-Adl A, Adouni M. Knee joint passive stiffness and moment in sagittal and frontal planes markedly increase with compression. Comput Methods Biomech Biomed Engin 2013; 18:339-50. [PMID: 23682906 DOI: 10.1080/10255842.2013.795555] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Knee joints are subject to large compression forces in daily activities. Due to artefact moments and instability under large compression loads, biomechanical studies impose additional constraints to circumvent the compression position-dependency in response. To quantify the effect of compression on passive knee moment resistance and stiffness, two validated finite element models of the tibiofemoral (TF) joint, one refined with depth-dependent fibril-reinforced cartilage and the other less refined with homogeneous isotropic cartilage, are used. The unconstrained TF joint response in sagittal and frontal planes is investigated at different flexion angles (0°, 15°, 30° and 45°) up to 1800 N compression preloads. The compression is applied at a novel joint mechanical balance point (MBP) identified as a point at which the compression does not cause any coupled rotations in sagittal and frontal planes. The MBP of the unconstrained joint is located at the lateral plateau in small compressions and shifts medially towards the inter-compartmental area at larger compression forces. The compression force substantially increases the joint moment-bearing capacities and instantaneous angular rigidities in both frontal and sagittal planes. The varus-valgus laxities diminish with compression preloads despite concomitant substantial reductions in collateral ligament forces. While the angular rigidity would enhance the joint stability, the augmented passive moment resistance under compression preloads plays a role in supporting external moments and should as such be considered in the knee joint musculoskeletal models.
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Affiliation(s)
- H Marouane
- a Division of Applied Mechanics, Department of Mechanical Engineering , École Polytechnique , P.O. Box 6079, Station 'Centre-Ville', Montréal , Québec , Canada H3C 3A7
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637
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Wang Y, Marshall KL, Baba Y, Lumpkin EA, Gerling GJ. Natural Variation in Skin Thickness Argues for Mechanical Stimulus Control by Force Instead of Displacement. Joint Eurohaptics Conf Symp Haptic Interfaces Virtual Environ Teleoper Syst 2013; 2013:645-650. [PMID: 24500653 DOI: 10.1109/whc.2013.6548484] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The neural response to touch stimuli is influenced by skin properties as well as the delivery of stimuli. Here, we compare stimuli controlled by displacement and force, and analyze the impact on firing rates of slowly adapting type I afferents as skin thickness and elasticity change. Uniaxial compression tests were used to measure the mechanical properties of mouse hind limb skin (n=5), resulting in a range of skin thickness measurements (211.6-530.6 μm) and hyper- and visco-elastic properties (average coefficient of variation=0.27).Values were integrated to an axisymmetric finite element model using an Ogden strain energy function. This calculated the propagation of surface loads to tactile end-organ locations, where maximum compressive stress and its rate were sampled and linearly regressed to firing rate. For the observed range of skin thickness, firing response was predicted under both force and displacement control of a ramp-and-hold stimulus. Over the ramp phase of stimulation, the variance in predicted firing rate was higher under displacement than under force control (22.2versus 4.9 Hz) with a similar trend in the sustained phase of stimulation (4.6versus1.3Hz). Given that skin thickness varies significantly between specimens, for human skin perhaps seven more so than for mice, the use of force control is predicted to decrease experimental variance in neurophysiological and psychophysical responses.
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Affiliation(s)
- Yuxiang Wang
- Department of Systems and Information Engineering, University of Virginia
| | - Kara L Marshall
- Dept. of Dermatology, Columbia University College of Physicians & Surgeons
| | - Yoshichika Baba
- Dept. of Physiology & Cellular Biophysics, Columbia University College of Physicians & Surgeons
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638
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Abstract
Giant left atrium is a rare condition, with a reported incidence of 0.3%, and following mainly rheumatic mitral valve disease. Although rheumatic heart disease represents the main cause of giant left atrium, other etiologies have been reported. Giant left atrium has significant hemodynamic effects and requires specific management. In this review, we present two cases, discuss the different definitions, etiologies, clinical presentation and management modalities.
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Affiliation(s)
- Ahmed El Maghraby
- Non-Invasive Cardiology, Department of Cardiology and Cardiothoracic Surgery, Heart Hospital, Hamad Medical Corporation, Doha, Qatar
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639
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Abstract
This article reviews a series of studies on the factors influencing sound quality preferences, mostly for jazz and classical music stimuli. The data were obtained using ratings of individual stimuli or using the method of paired comparisons. For normal-hearing participants, the highest ratings of sound quality were obtained when the reproduction bandwidth was wide (55 to 16000 Hz) and ripples in the frequency response were small (less than ± 5 dB). For hearing-impaired participants listening via a simulated five-channel compression hearing aid with gains set using the CAM2 fitting method, preferences for upper cutoff frequency varied across participants: Some preferred a 7.5- or 10-kHz upper cutoff frequency over a 5-kHz cutoff frequency, and some showed the opposite preference. Preferences for a higher upper cutoff frequency were associated with a shallow high-frequency slope of the audiogram. A subsequent study comparing the CAM2 and NAL-NL2 fitting methods, with gains slightly reduced for participants who were not experienced hearing aid users, showed a consistent preference for CAM2. Since the two methods differ mainly in the gain applied for frequencies above 4 kHz (CAM2 recommending higher gain than NAL-NL2), these results suggest that extending the upper cutoff frequency is beneficial. A system for reducing "overshoot" effects produced by compression gave small but significant benefits for sound quality of a percussion instrument (xylophone). For a high-input level (80 dB SPL), slow compression was preferred over fast compression.
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Affiliation(s)
- Brian C J Moore
- Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge, CB2 3EB England, UK.
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640
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Malhotra NR, Han WM, Beckstein J, Cloyd J, Chen W, Elliott DM. An injectable nucleus pulposus implant restores compressive range of motion in the ovine disc. Spine (Phila Pa 1976) 2012; 37:E1099-105. [PMID: 22588378 DOI: 10.1097/BRS.0b013e31825cdfb7] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Investigation of injectable nucleus pulposus (NP) implant. OBJECTIVE To assess the ability of a recently developed injectable hydrogel implant to restore nondegenerative disc mechanics through support of NP functional mechanics. SUMMARY OF BACKGROUND DATA Although surgical intervention for low back pain is effective for some patients, treated discs undergo altered biomechanics and adjacent levels are at increased risk for accelerated degeneration. One potential treatment as an alternative to surgery for degenerated disc includes the percutaneous delivery of agents to support NP functional mechanics. The implants are delivered in a minimally invasive fashion, potentially on an outpatient basis, and do not preclude later surgical options. One of the challenges in designing such implants includes the need to match key NP mechanical behavior and mimic the role of native nondegenerate NP in spinal motion. METHODS The oxidized hyaluronic acid gelatin implant material was prepared. In vitro mechanical testing was performed in mature ovine bone-disc-bone units in 3 stages: intact, discectomy, and implantation versus sham. Tested samples were cut axially for qualitative structural observations. RESULTS Discectomy increased axial range of motion (ROM) significantly compared with intact. Hydrogel implantation reduced ROM 17% (P < 0.05) compared with discectomy and returned ROM to intact levels (ROM intact 0.71 mm, discectomy 0.87 mm, postimplantation 0.72 mm). Although ROM for the hydrogel implant group was statistically unchanged compared with the intact disc, ROM for sham discs, which received a discectomy and no implant, was significantly increased compared with intact. The compression and tension stiffness were decreased with discectomy and remained unchanged for both implant and sham groups as expected because the annulus fibrosus was not repaired. Gross morphology images confirmed no ejection of NP implant. CONCLUSION An injectable implant that mimics nondegenerate NP has the potential to return motion segment ROM to normal subsequent to injury.
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641
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Abstract
Archives operating under the International Nucleotide Sequence Database Collaboration currently preserve all submitted sequences equally, but rapid increases in the rate of global sequence production will soon require differentiated treatment of DNA sequences submitted for archiving. Here, we propose a graded system in which the ease of reproduction of a sequencing-based experiment and the relative availability of a sample for resequencing define the level of lossy compression applied to stored data.
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Affiliation(s)
- Guy Cochrane
- EMBL-Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SD, United Kingdom
| | - Charles E Cook
- EMBL-Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SD, United Kingdom
| | - Ewan Birney
- EMBL-Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SD, United Kingdom
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642
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Wu SC, Crews RT, Najafi B, Slone-Rivera N, Minder JL, Andersen CA. Safety and efficacy of mild compression (18-25 mm Hg) therapy in patients with diabetes and lower extremity edema. J Diabetes Sci Technol 2012; 6:641-7. [PMID: 22768895 PMCID: PMC3440039 DOI: 10.1177/193229681200600319] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Patients with diabetes often present with lower extremity (LE) edema; however, because of concomitant peripheral arterial disease, compression therapy is generally avoided by providers in fear of compromising arterial circulation. This pilot study sought to assess whether diabetic socks with mild compression (18-25 mm Hg) can reduce LE edema in patients with diabetes without negatively impacting vascularity. METHODS Eighteen subjects (9 males, 9 females) aged 61 ± 11 years with diabetes, LE edema, and a mean ankle-brachial index (ABI) of 1.10 ± 0.21 successfully completed this uncontrolled study. At baseline, subjects were fitted and instructed to wear the socks during all waking hours. Follow-up visits occurred weekly for four consecutive weeks. Edema was quantified through midfoot, ankle, and calf circumferences and cutaneous fluid measurements. Vascular status was tracked via ABI. RESULTS Repeated measures analysis of variance and least significant difference post hoc analyses were used for data analyses. Calf circumferences showed a statistically significant (p < .05) decrease of 1.3 ± 0.28 cm after just one week and remained significantly smaller than baseline throughout the study. Foot circumferences were significantly reduced at week 2 (-0.98 ± 0.35 cm) and remained significantly below baseline for the remainder of the study. The ankle also demonstrated a trend of circumference reduction but was not statistically significant. Cutaneous edema significantly reduced by week 3 (-3.1 ± 1.3 U) and remained so at week 4. Ankle-brachial index significantly increased (0.14 ± 0.049) at week 2 but was not significantly higher at weeks 3 or 4. No adverse events occurred during the study. CONCLUSIONS Mild compression therapy (18-25 mm Hg) decreased swelling in diabetes patients with LE edema without compromising vascularity.
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Affiliation(s)
- Stephanie C Wu
- Center for Lower Extremity Ambulatory Research, Dr. William M. Scholl College of Podiatric Medicine at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064, USA.
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643
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Abstract
In spite of the recognized importance of tandem duplications in genome evolution, commonly adopted sequence comparison algorithms do not take into account complex mutation events involving more than one residue at the time, since they are not compliant with the underlying assumption of statistical independence of adjacent residues. As a consequence, the presence of tandem repeats in sequences under comparison may impair the biological significance of the resulting alignment. Although solutions have been proposed, repeat-aware sequence alignment is still considered to be an open problem and new efficient and effective methods have been advocated. The present paper describes an alternative lossy compression scheme for genomic sequences which iteratively collapses repeats of increasing length. The resulting approximate representations do not contain tandem duplications, while retaining enough information for making their comparison even more significant than the edit distance between the original sequences. This allows us to exploit traditional alignment algorithms directly on the compressed sequences. Results confirm the validity of the proposed approach for the problem of duplication-aware sequence alignment.
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Affiliation(s)
- Valerio Freschi
- Department of Base Sciences and Fundamentals, University of Urbino, Italy
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644
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Lucas RAI, Ainslie PN, Morrison SA, Cotter JD. Compression leggings modestly affect cardiovascular but not cerebrovascular responses to heat and orthostatic stress in young and older adults. Age (Dordr) 2012; 34:439-49. [PMID: 21526339 PMCID: PMC3312639 DOI: 10.1007/s11357-011-9250-4] [Citation(s) in RCA: 12] [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: 07/07/2010] [Accepted: 04/10/2011] [Indexed: 05/17/2023]
Abstract
We tested the hypothesis that wearing commercially available compression leggings would attenuate postural reductions in mean arterial blood pressure (MAP) and cerebral perfusion during heat stress, particularly in older adults. Six older (70 years ± 4) and six younger (29 years ± 4) males were heated (esophageal temperature raised 0.5°C) in a water-perfused suit whilst wearing compression or control leggings (>1 week apart, randomized order). Blood flow velocity in the middle cerebral artery (MCAv), blood pressure (photoplethysmography), total peripheral resistance (TPR; ModelFlow) and the partial pressure of end-tidal carbon dioxide were measured continuously before and during 3-min standing in each thermal state. When supine, compression leggings did not change any cardiorespiratory variables in either age group or thermal condition (P > 0.05). Upon standing, wearing compression leggings delayed (~15%; P = 0.044) the maximal drop (nadir) in MAP irrespective of age or thermal condition. During the last minute of standing, wearing compression leggings in normothermia increased TPR (+16%) in older participants but dropped TPR (-8%) in younger participants (P = 0.004 compression × age group). When standing and heated, wearing compression leggings lowered TPR in older and younger participants (~43%; P < 0.01) without changing MAP or MCAv (P > 0.05). In older adults, when standing, compression leggings maintained MAP by elevating TPR. In contrast, under combined heat and orthostatic stress, wearing compression leggings dropped TPR in both older and younger adults, though MAP and MCAv were maintained.
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645
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Abstract
We present a 45-year-old patient who had acute radial nerve palsy following a blunt trauma without any fracture or dislocation. He was injured by strucking in a combat three months ago. The patient has been followed by application of a long-arm plaster cast before referred to our clinic. Preoperative electromyoneurography and magnetic resonance imaging (MRI) indicated that there was a radial nerve injury on humeral groove. The British Medical Research Council (MRC) grade was 2/5 on his wrist preoperatively. The patient underwent an operation under general anesthesia. It was seen to be a second-degree nerve injury. The patient has subsequently regained full movement on his wrist and finger extension in six months. We suggest that a detailed clinical and electrodiagnostical evaluation is necessary in patients who have radial nerve injury when deciding the treatment, conservative or surgical.
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Affiliation(s)
- Umut Tuncel
- Department of Plastic Reconstructive and Aesthetic Surgery, Gaziosmanpasa University, Faculty of Medicine 60100, Tokat, Turkey
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646
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Rosenholtz R, Huang J, Ehinger KA. Rethinking the role of top-down attention in vision: effects attributable to a lossy representation in peripheral vision. Front Psychol 2012; 3:13. [PMID: 22347200 PMCID: PMC3272623 DOI: 10.3389/fpsyg.2012.00013] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Accepted: 01/11/2012] [Indexed: 11/21/2022] Open
Abstract
According to common wisdom in the field of visual perception, top-down selective attention is required in order to bind features into objects. In this view, even simple tasks, such as distinguishing a rotated T from a rotated L, require selective attention since they require feature binding. Selective attention, in turn, is commonly conceived as involving volition, intention, and at least implicitly, awareness. There is something non-intuitive about the notion that we might need so expensive (and possibly human) a resource as conscious awareness in order to perform so basic a function as perception. In fact, we can carry out complex sensorimotor tasks, seemingly in the near absence of awareness or volitional shifts of attention ("zombie behaviors"). More generally, the tight association between attention and awareness, and the presumed role of attention on perception, is problematic. We propose that under normal viewing conditions, the main processes of feature binding and perception proceed largely independently of top-down selective attention. Recent work suggests that there is a significant loss of information in early stages of visual processing, especially in the periphery. In particular, our texture tiling model (TTM) represents images in terms of a fixed set of "texture" statistics computed over local pooling regions that tile the visual input. We argue that this lossy representation produces the perceptual ambiguities that have previously been as ascribed to a lack of feature binding in the absence of selective attention. At the same time, the TTM representation is sufficiently rich to explain performance in such complex tasks as scene gist recognition, pop-out target search, and navigation. A number of phenomena that have previously been explained in terms of voluntary attention can be explained more parsimoniously with the TTM. In this model, peripheral vision introduces a specific kind of information loss, and the information available to an observer varies greatly depending upon shifts of the point of gaze (which usually occur without awareness). The available information, in turn, provides a key determinant of the visual system's capabilities and deficiencies. This scheme dissociates basic perceptual operations, such as feature binding, from both top-down attention and conscious awareness.
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Affiliation(s)
- Ruth Rosenholtz
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridge, MA, USA
- Computer Science and Artificial Intelligence Lab, Massachusetts Institute of TechnologyCambridge, MA, USA
| | - Jie Huang
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridge, MA, USA
| | - Krista A. Ehinger
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridge, MA, USA
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647
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Abstract
This article explores the professional challenges of treating patients with complex/severe forms of chronic oedema/lymphoedema with compression therapy. Four focus groups were held, two in the UK and two in Canada, to examine the challenges faced by practitioners in their everyday practice. A number of challenges were identified by participants in both countries and include the changing profile of lymphoedema/chronic oedema and how increasing complexity is outpacing the development of services and research-based guidelines. Focus groups also highlighted a lack of public awareness, poor professional knowledge, delayed diagnosis and inappropriate treatment as having a significant impact on practice. Other practice-related issues include a poor understanding of treatment options among practitioners, a lack of evidence-based practice as well as difficulties associated with managing psychosocial problems and of ensuring concordance with treatment. In Canada, services tend to be more rural and remote than in the UK, autonomous specialist practice is less developed and practitioners were generally less confident and felt more vulnerable than their UK colleagues. There is a need for integrated, multi-disciplinary services in both countries, with improved education and training, as well as the development of cost-effective compression bandaging systems that can make a major contribution to meeting the challenges of contemporary lymphoedema practice.
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Affiliation(s)
- Philip A Morgan
- Centre for Research and Implementation of Clinical Practice, St Luke's Crypt, Sydney Street, London SW3 6NH, UK.
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648
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Roaldsen KS, Elfving B, Stanghelle JK, Mattsson E. Effect of multilayer high- compression bandaging on ankle range of motion and oxygen cost of walking. Phlebology 2012; 27:5-12. [PMID: 21810941 PMCID: PMC3257002 DOI: 10.1258/phleb.2011.010084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2011] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To evaluate the effects of multilayer high-compression bandaging on ankle range of motion, oxygen consumption and subjective walking ability in healthy subjects. METHOD A volunteer sample of 22 healthy subjects (10 women and 12 men; aged 67 [63-83] years) were studied. The intervention included treadmill-walking at self-selected speed with and without multilayer high-compression bandaging (Proforeº), randomly selected. The primary outcome variables were ankle range of motion, oxygen consumption and subjective walking ability. RESULTS Total ankle range of motion decreased 4% with compression. No change in oxygen cost of walking was observed. Less than half the subjects reported that walking-shoe comfort or walking distance was negatively affected. CONCLUSION Ankle range of motion decreased with compression but could probably be counteracted with a regular exercise programme. There were no indications that walking with compression was more exhausting than walking without. Appropriate walking shoes could seem important to secure gait efficiency when using compression garments.
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Affiliation(s)
- K S Roaldsen
- Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, 23100, SE-14183 Huddinge, Sweden.
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649
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Abstract
UNLABELLED The objective is to find a practical balance between quality and performance for daily high volume whole slide imaging. We evaluated whole slide images created by various scanners at different compression factors to determine the best suitable quality factor (QF) needed for pathological images of special stains. METHOD We scanned two sets of eight special stains slides each at 0.50 μm/pixel resolution in Hamamatsu scanner at six and five QF levels respectively to generate 72 images which were observed at a calibrated monitor by imaging specialists, a histo-technician, and a pathologist to find the most suitable QF level for special stains in digital slides. RESULTS Most special stains images were acceptable at QF 30 except for the stain Reticulin where the lowest acceptable QF was 50. The compression of images from QF 90 to QF 50 reduced the size of the images by 62.73%. CONCLUSION 0.50 μm/pixel images at QF 50 or above were found suitable 12 special stain.
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650
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Morgan PA, Murray S, Moffatt CJ, Young H. The experience of patients with lymphoedema undergoing a period of compression bandaging in the UK and Canada using the 3M™ Coban™ 2 compression system. Int Wound J 2011; 8:586-98. [PMID: 21848728 PMCID: PMC7950657 DOI: 10.1111/j.1742-481x.2011.00832.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
This article reports on a qualitative study that explored the experience of patients who have undergone a period of complete decongestive therapy using the 3M™ Coban™ 2 compression system (Coban 2 system). Qualitative data were collected from 12 patients from the UK and 8 from Canada with a range of presentations of lymphoedema. Single semi-structured interviews were used and participants were asked questions relating to their experience of diagnosis, the impact of lymphoedema on their lives, previous treatment using multilayer lymphoedema bandaging and their experiences of the 3M™ Coban™ 2 system. Treatment with multilayer lymphoedema bandaging was seen as constraining in that it was tiring, time consuming, heavy, bulky and led to feelings of clumsiness and a restricted life. Treatment with the 3M™ Coban™ 2 system was reported as enabling in that it was quicker and easier to apply, increased mobility, enhanced patient confidence and provided a sense of control and well-being. The article also explores how aspects of the 3M™ Coban™ 2 system might be improved from the patient's point of view.
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Affiliation(s)
- Philip A Morgan
- Centre for Research and Implementation of Clinical Practice, London, UK.
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