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1.
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   
2.
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   
3.
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   
4.
During January 2013–August 2014, a total of 1,800 patients in Iran who had respiratory illness were tested for Middle East respiratory syndrome coronavirus. A cluster of 5 cases occurred in Kerman Province during May–July 2014, but virus transmission routes for some infections were unclear.  相似文献   
5.
Journal of Digital Imaging - Accurate information of the lung shape analysis and its anatomical variations is very noticeable in medical imaging. The normal variations of the lung shape can be...  相似文献   
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7.

Purpose

This study aimed at comparing the development of tricuspid and mitral regurgitation between the right ventricular outflow tract (RVOT) and right ventricular apex (RVA) pacing.

Methods

We prospectively enrolled 164 patients for permanent pacemaker implantation due to sick sinus syndrome or atrioventricular block and randomly divided them into two equal groups to receive either RVOT or RVA pacing. Patients with heart failure or valvular disease were excluded. The post-procedural echocardiographic evaluations were performed 1 year after the pre-procedural echocardiography, and the results were compared with respect to the development of mitral and tricuspid regurgitation and probable changes in the ejection fraction (EF).

Results

Age, gender, pacing mode, and baseline cardiac rhythm did not significantly differ between the RVOT and RVA pacing groups. The incidence of mitral regurgitation was significantly higher in the RVA group (p?=?0.03), but the incidence of tricuspid regurgitation was similar in both groups. There was a trend toward less tricuspid regurgitation in the RVOT group; however, it was not statistically significant. The mean EF was not significantly different between the study groups.

Conclusion

It seems that the incidence of mitral regurgitation in RVA pacing is significantly higher than that in RVOT pacing. The formation of tricuspid regurgitation needs to be discussed in the future.

Clinical trial registration number

IRCT201103146061N1  相似文献   
8.
Electrical and structural remodeling during the progression of cardiovascular disease is associated with adverse outcomes subjecting affected patients to overt heart failure (HF) and/or sudden death. Dysfunction in integral membrane protein trafficking has long been linked with maladaptive electrical remodeling. However, little is known regarding the molecular identity or function of these intracellular targeting pathways in the heart. Eps15 homology domain-containing (EHD) gene products (EHD1-4) are polypeptides linked with endosomal trafficking, membrane protein recycling, and lipid homeostasis in a wide variety of cell types. EHD3 was recently established as a critical mediator of membrane protein trafficking in the heart. Here, we investigate the potential link between EHD3 function and heart disease. Using four different HF models including ischemic rat heart, pressure overloaded mouse heart, chronic pacing-induced canine heart, and non-ischemic failing human myocardium we provide the first evidence that EHD3 levels are consistently increased in HF. Notably, the expression of the Na/Ca exchanger (NCX1), targeted by EHD3 in heart is similarly elevated in HF. Finally, we identify a molecular pathway for EHD3 regulation in heart failure downstream of reactive oxygen species and angiotensin II signaling. Together, our new data identify EHD3 as a previously unrecognized component of the cardiac remodeling pathway.  相似文献   
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10.
ObjectivesPrimary carcinomas of the urethra (PCU) are rare and often advanced when diagnosed. Treatment standards are lacking. We studied treatment response and survival in a cohort of patients with PCU, with emphasis on modern platinum-containing chemotherapy regimens plus surgery for advanced disease.Materials and methodsThis was a retrospective chart review of consecutive patients with PCU seen by medical oncologists at our institution over a recent 5-year period. Outcome was measured as best response to chemotherapy. Kaplan-Meier estimates were generated for survival and Cox proportional hazard was used for prognostic factors for survival.ResultsThe 44 patients (64% women) included had a median age at diagnosis of 66.5 years. The most prevalent histologic subtypes of PCU were squamous cell carcinoma and adenocarcinoma. At diagnosis, 43% already had lymph node-positive [lymph node (LN)+] disease, and 16% had distant metastases. The entire cohort's overall survival (OS) was 31.7 months. The response rate to platinum-containing neoadjuvant chemotherapy was 72%. Twenty-one patients with locally advanced or LN+ PCU underwent chemotherapy plus surgery. Their median OS from chemotherapy initiation was 25.6 months. Four of 9 patients (44%) with LN+ PCU at diagnosis were alive at our review, with a minimum follow-up of more than 3 years.ConclusionsModern platinum-containing regimens appear to be effective in advanced PCU. Preoperative chemotherapy is associated with prolonged disease-free survival in a subgroup of LN+ cases.  相似文献   
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