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Cardiovascular Drugs and Therapy - Available animal models of acute heart failure (AHF) and their limitations are discussed herein. A novel and preclinically relevant porcine model of decompensated...  相似文献   
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In December 2019 a novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), started spreading from Wuhan city of Chinese Hubei province and rapidly became a global pandemic. Clinical symptoms of the disease range from paucisymptomatic disease to a much more severe disease. Typical symptoms of the initial phase include fever and cough, with possible progression to acute respiratory distress syndrome. Gastrointestinal manifestations such as diarrhoea, vomiting and abdominal pain are reported in a considerable number of affected individuals and may be due to the SARS-CoV-2 tropism for the peptidase angiotensin receptor 2. The intestinal homeostasis and microenvironment appear to play a major role in the pathogenesis of COVID-19 and in the enhancement of the systemic inflammatory responses. Long-term consequences of COVID-19 include respiratory disturbances and other disabling manifestations, such as fatigue and psychological impairment. To date, there is a paucity of data on the gastrointestinal sequelae of SARS-CoV-2 infection. Since COVID-19 can directly or indirectly affect the gut physiology in different ways, it is plausible that functional bowel diseases may occur after the recovery because of potential pathophysiological alterations (dysbiosis, disruption of the intestinal barrier, mucosal microinflammation, post-infectious states, immune dysregulation and psychological stress). In this review we speculate that COVID-19 can trigger irritable bowel syndrome and we discuss the potential mechanisms.  相似文献   
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Background::Soft tissue sarcoma (STS) is a heterogeneous group of rare neoplasms whose aetiology is largely unknown. Dioxin and dioxin-like compounds, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and polychlorinated biphenyls (PCBs), are potential risk factors for STS.Objectives:To investigate the relation of 17 PCBs congeners, assessed in human plasma, with STS risk.Methods:We conducted a case-control study in Italy, including 52 STS cases and 99 hospital-based controls. Selected PCB were extracted by high-performance liquid chromatography (HPLC) and measured with gas chromatography-mass spectrometry (GC-MS). Odds ratios (OR), and the corresponding 95% confidence intervals (CI), were estimated through multivariate logistic regression models.Results:The most frequently detected PCB congeners were 138, 170, 180 and 149 (detected in 40-77% of controls). The OR for the sum of all 17 PCB congeners was 1.20 (95% CI 0.50-2.92). In categorical analysis no consistent association was found for individual congeners and for groups based on Wolff’s classification or the degree of chlorination. For continuous estimates, borderline positive associations emerged for Wolff’s groups 2A (OR 1.23, 95% CI 0.97-1.55), 2B (OR 1.34, 95% CI 1.00-1.77, and 3 (OR 1.19, 95% CI 0.96-1.49), for moderately (OR 1.20, 95% CI 0.96-1.51) and highly (OR 1.18, 95% CI 0.99-1.41) chlorinated PCBs, and for congeners 170 (OR 1.26, 95% CI 0.98-1.63), 180 (OR 1.26, 95% CI 0.97-1.64) and 138 (OR 1.45, 95% CI 1.02-2.04).Discussion:Most associations between PCBs and STS risk were not significant, but, given the limited sample size, we cannot exclude moderate associations.Key words: Soft tissue sarcoma, polychlorinated biphenyls, epidemiology, environmental risk factors, chemical contaminants, case-control study  相似文献   
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Background

Pazopanib has been approved for first-line treatment of patients with metastatic renal-cell carcinoma on the basis of clinical trials that enrolled only patients with adequate renal function. Few data are available on the safety and efficacy of pazopanib in patients with renal insufficiency. This study investigated the effect of kidney function on treatment outcomes in such patients.

Patients and Methods

We retrospectively analyzed data of metastatic renal-cell carcinoma patients treated with pazopanib from January 2010 to June 2016 with respect to renal function. Patients with Modification of Diet in Renal Disease ≤ 60 mL/min/1.73 m2 (group A) were compared to patients with Modification of Diet in Renal Disease > 60 mL/min/1.73 m2 (group B) in terms of progression-free survival, toxicities, response rates, and overall survival.

Results

A total of 229 patients were included: 128 in group A and 101 in group B. Median progression-free survival was 14 months (95% confidence interval [CI], 9.4-18.5) and 17 months (95% CI, 11.4-22.8), and overall survival was 30.5 months (95% CI, 8-53) and 41.4 months (95% CI, 21-62) for group A and group B, respectively, with no significant difference (P = .6). No significant difference between the 2 groups was reported in the incidence of adverse events. Dose reductions were more frequent in group A patients (66% vs. 36%; P = .04).

Conclusion

Although the dose of pazopanib was reduced more frequently in patients with renal impairment, kidney function at therapy initiation does not adversely affect the safety and efficacy of pazopanib.  相似文献   
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Tendon injuries are a common cause of morbidity in humans. They also occur frequently in horses, and the horse provides a relevant, large animal model in which to test novel therapies. To develop novel cell therapies that can aid tendon regeneration and reduce subsequent reinjury rates, the mechanisms that control tendon tissue regeneration and matrix remodelling need to be better understood. Although a range of chemical cues have been explored (growth factors, media etc.), the influence of the mechanical environment on tendon cell culture has yet to be fully elucidated. To mimic the in vivo environment, in this study, we have utilised a novel and affordable, custom‐made bioreactor to apply a cyclical strain to tendon‐like constructs generated in three‐dimensional (3D) culture by equine tenocytes. Dynamic shear analysis (DSA), dynamic scanning calorimetry (DSC) and Fourier‐transform infrared (FTIR) spectroscopy were used to determine the mechanical and chemical properties of the resulting tendon‐like constructs. Our results demonstrate that equine tenocytes exposed to a 10% cyclical strain have an increased amount of collagen gel contraction after 7 and 8 days of culture compared with cells cultured in 3D in the absence of external strain. While all the tendon‐like constructs have a very similar chemical composition to native tendon, the application of strain improves their mechanical properties. We envisage that these results will contribute towards the development of improved biomimetic artificial tendon models for the development of novel strategies for equine regenerative therapies.  相似文献   
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