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Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems.  相似文献   
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STUDY DESIGN: A combined experimental and theoretical biomechanical study to quantify the mechanical properties of living cells of the porcine intervertebral disc. OBJECTIVES: To quantify zonal variations in the mechanical properties and morphology of cells isolated from the intervertebral disc. SUMMARY OF BACKGROUND DATA: Cellular response to mechanical stimuli is influenced by the mechanical properties of cells and of the extracellular matrix. Significant zonal variations in intervertebral disc matrix properties have been reported. No information is currently available on the corresponding regional variations in the mechanical properties of intervertebral disc cells, despite evidence of significant differences in cellular phenotype and biologic response to loading. METHODS: The micropipette aspiration test was used in combination with a three-parameter viscoelastic solid model to measure the mechanical properties of cells isolated from the anulus fibrosus, transition zone, and nucleus pulposus. RESULTS: Intervertebral disc cells exhibited viscoelastic solid behaviors. Highly significant differences were observed in the morphology, cytoskeletal arrangement, and biomechanical properties of the nucleus pulposus cells as compared with anulus fibrosus or transition zone cells. Cells of the nucleus pulposus were approximately three times stiffer and significantly more viscous than cells of the anulus fibrosus or transition zone. CONCLUSIONS: The findings of this study provide new evidence for the existence of two biomechanically distinct cell populations in the intervertebral disc. These differences in mechanical behavior may be related to observed differences in the cytoskeletal architecture between these cells, and may further play an important role in the development, maintenance, and degeneration of the intervertebral disc.  相似文献   
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Objective: Uterine leiomyoma (UL) can be considered as the most common benign gynecological tumors of the smooth muscle cells in the myometrium. They are likely to be associated with infertility and recurrent abortion as well as obstructed labor and post-partum hemorrhage. Moreover, altered vascular-related genes can be linked to developing leiomyoma. Polymorphisms of the angiotensin-converting enzyme (ACE) gene are associated with some vascular diseases. The present study was carried out to investigate the association of ACE I/D and AGTR1 A1166C gene polymorphisms and the risk of uterine leiomyoma in a sample of Iranian population. Methods: The study was carried out on a total of 413 women divided into 202 patients with diagnosed uterine leiomyomas and a control group of 211. Genotyping was performed using the PCR or PCR-RFLP methods. Results: The ID and DD genotypes of ACE I/D polymorphism were associated with 2 and 2.9 fold higher risk of UL compared to II genotype (OR, 2 [95% CI, 1.3 to 3.2]; P = 0.004 and OR, 2.9 [95% CI, 1.6 to 5]; P = 0.0002). The frequencies of ACE D alleles were 53.7% in women with UL and 40.3% in controls, which were observed to be statistically different (P < 0.0001). The alleles and genotypes of AGTR1 A1166C polymorphism were not different between UL and control women (P=0.9). Conclusion: The ACE ID and DD genotypes were associated with a higher risk of UL. No relationship was found between AGTR1 A1166C polymorphism and UL.  相似文献   
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Post‐traumatic arthritis (PTA) frequently develops after intra‐articular fracture of weight bearing joints. Loss of cartilage viability and post‐injury inflammation have both been implicated as possible contributing factors to PTA progression. To further investigate chondrocyte response to impact and fracture, we developed a blunt impact model applying 70%, 80%, or 90% surface‐to‐surface compressive strain with or without induction of an articular fracture in a cartilage explant model. Following mechanical loading, chondrocyte viability, and apoptosis were assessed. Culture media were evaluated for the release of double‐stranded DNA (dsDNA) and immunostimulatory activity via nuclear factor kappa B (NF‐κB) activity in Toll‐like receptor (TLR) ‐expressing Ramos‐Blue reporter cells. High compressive strains, with or without articular fracture, resulted in significantly reduced chondrocyte viability. Blunt impact at 70% strain induced a loss in viability over time through a combination of apoptosis and necrosis, whereas blunt impact above 80% strain caused predominantly necrosis. In the fracture model, a high level of primarily necrotic chondrocyte death occurred along the fracture edges. At sites away from the fracture, viability was not significantly different than controls. Interestingly, both dsDNA release and NF‐κB activity in Ramos‐Blue cells increased with blunt impact, but was only significantly increased in the media from fractured cores. This study indicates that the mechanism of trauma determines the type of chondrocyte death and the potential for post‐injury inflammation. (c) 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1283–1292, 2013  相似文献   
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With the successful uptake and inclusion of robotic systems in minimally invasive surgery and with the increasing application of robotic surgery (RS) in numerous surgical specialities worldwide, there is now a need to develop and enhance the technology further. One such improvement is the implementation and amalgamation of haptic feedback technology into RS which will permit the operating surgeon on the console to receive haptic information on the type of tissue being operated on. The main advantage of using this is to allow the operating surgeon to feel and control the amount of force applied to different tissues during surgery thus minimising the risk of tissue damage due to both the direct and indirect effects of excessive tissue force or tension being applied during RS. We performed a two-rater systematic review to identify the latest developments and potential avenues of improving technology in the application and implementation of haptic feedback technology to the operating surgeon on the console during RS. This review provides a summary of technological enhancements in RS, considering different stages of work, from proof of concept to cadaver tissue testing, surgery in animals, and finally real implementation in surgical practice. We identify that at the time of this review, while there is a unanimous agreement regarding need for haptic and tactile feedback, there are no solutions or products available that address this need. There is a scope and need for new developments in haptic augmentation for robot-mediated surgery with the aim of improving patient care and robotic surgical technology further.  相似文献   
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The development of regenerative therapies for cartilage injury has been greatly aided by recent advances in stem cell biology. Induced pluripotent stem cells (iPSCs) have the potential to provide an abundant cell source for tissue engineering, as well as generating patient-matched in vitro models to study genetic and environmental factors in cartilage repair and osteoarthritis. However, both cell therapy and modeling approaches require a purified and uniformly differentiated cell population to predictably recapitulate the physiological characteristics of cartilage. Here, iPSCs derived from adult mouse fibroblasts were chondrogenically differentiated and purified by type II collagen (Col2)-driven green fluorescent protein (GFP) expression. Col2 and aggrecan gene expression levels were significantly up-regulated in GFP+ cells compared with GFP− cells and decreased with monolayer expansion. An in vitro cartilage defect model was used to demonstrate integrative repair by GFP+ cells seeded in agarose, supporting their potential use in cartilage therapies. In chondrogenic pellet culture, cells synthesized cartilage-specific matrix as indicated by high levels of glycosaminoglycans and type II collagen and low levels of type I and type X collagen. The feasibility of cell expansion after initial differentiation was illustrated by homogenous matrix deposition in pellets from twice-passaged GFP+ cells. Finally, atomic force microscopy analysis showed increased microscale elastic moduli associated with collagen alignment at the periphery of pellets, mimicking zonal variation in native cartilage. This study demonstrates the potential use of iPSCs for cartilage defect repair and for creating tissue models of cartilage that can be matched to specific genetic backgrounds.  相似文献   
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