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91.
92.
Delayed graft function (DGF) results from ischemia‐reperfusion injury (IRI) and the generation of reactive oxygen species. We hypothesized that NADPH oxidase 2 (Nox2) plays an important role in pathways leading to DGF. We tested this hypothesis in vitro, in an animal model of IRI using wild type and Nox2?/? mice, and in patients with DGF. Under hypoxic conditions, primary tubular epithelial cells from Nox2?/? mice had reduced expression of MMP2, vimentin, and HSP27. BUN and creatinine levels were significantly increased in both Nox2?/? and WT mice at 4 weeks and 6 months after IRI, suggesting the development of acute and chronic kidney injury. At 4 weeks, kidney fibrosis (α‐SMA, picrosirius) and oxidative stress (dihydroethidine, HNE) were significantly reduced in Nox2?/? mice, confirming the oxidative and pro‐fibrotic effects of Nox2. The molecular signature of IRI using genomic analyses demonstrated a significant decline in hypoxia reponse, oxidative stress, fibrosis, and inflammation in Nox2?/? mice. Immunohistochemical analyses of pre‐implanatation kidney allograft biopsies from patients with subsequent DGF showed significantly greater Nox2 levels and vascular injury compared with patients without DGF. These studies demonstrate that Nox2 is a modulator of IRI and its absence is associated with reduced inflammation, OS, and fibrosis.
  相似文献   
93.
Previously designed intra-thoracic paraaortic counterpulsation device has limited stroke volume and may depress the lung to cause complications. The purpose of this study was to evaluate the hemodynamic effects of an extra-thoracic paraaortic counterpulsation device (ETPACD) in comparison to intraaortic balloon pump (IABP) in an animal model with acute heart failure. The acute heart failure model was successfully induced by snaring branch of anterior descending coronary artery in sheep (weighting, 38-50 kg, n = 8). The ETPACD is a single port, 65-ml stroke volume blood chamber designed to be connected to descending aorta through a valveless graft and placed extra-thorax. In comparison, a standard clinical 40-ml IABP was placed in the descending aorta. The hemodynamic indices of both devices were recorded during counterpulsation assistance. Two of the sheep were allowed to survive for 1 week to examine the prolonged effect. Both ETPACD and IABP increased cardiac output with higher effect of ETPACD (13.52 % vs. 8.19 % in IABP, P < 0.05) and on mean diastolic aortic pressure (26.73 % vs. 12.58 % in IABP, P < 0.01). Both ETPACD and IABP also produced a greater reduction in left ventricular end-diastolic pressure (26.77 % vs. 23.08 %, P > 0.05). The ETPACD increased left carotid artery flow more significantly the IABP (18.00 % vs. 9.19 % , P < 0.05). In two of the sheep allowed to survive for 1 week, the device worked well with no complications and there was no thrombus formation in the chamber of ETPACD. This study demonstrated that both ETPACD and IABP provided benefit of circulatory support in acute heart failure with better effect on hemodynamic parameters provided by ETPACD. Therefore, ETPACD with theoretical larger stroke volume may become a promising counterpulsation device for treatment of heart failure.  相似文献   
94.
Ohnishi in 1975 first described temporomandibular joint (TMJ) arthroscopy. Along with its extensive use, a range of complications has emerged. We describe a patient who experienced parapharyngeal swelling after undergoing arthroscopy. Prolonged intubation up to 1 hour postoperatively was required. The swelling resolved completely over 6 h without further intervention.  相似文献   
95.
Concerns are often raised regarding potentially adverse effects of antiretroviral therapy (ART) on health-related quality of life (HRQoL), but there is limited longitudinal data to prove this. Building on our prior investigation, we examined the impact of ART on HRQoL among HIV-infected South African women with extensive follow-up in the CAPRISA 002 Acute Infection Cohort Study. Overall HRQoL and five sub-domains [physical well-being (PWB), emotional well-being (EWB), functional and global well-being (FGWB), social well-being (SWB) and cognitive functioning (CF)] were assessed using the Functional Assessment of HIV Infection (FAHI) instrument. Our analyses comparing FAHI scores between pre-ART (established infection) and ART phases using paired Wilcoxon signed-rank tests and adjusted mixed-effects regression models revealed improvements on ART in overall HRQoL, and in PWB, EWB, and SWB, but not in FGWB and CF. No long-term adverse impact of ART on HRQoL was detected, providing additional non-biomedical support to early treatment strategies.  相似文献   
96.
Young women in sub-Saharan Africa are disproportionately affected by HIV, making the development of women initiated and controlled methods of prevention, including microbicides, a priority. Adherence is pivotal to microbicide efficacy and partner related factors are known to impact adherence. An analysis of disclosure of gel use to sexual partners and adherence in CAPRISA 004 women was conducted to better understand this relationship. Partner disclosure was significantly associated with a modest 4.2 % increased adherence (71.0 vs. 66.8 %, p = 0.03). Most women rated the experience of disclosure as positive, despite 6.7 % of partners expressing a negative reaction.Participants who disclosed were more likely to reside with their regular partner (14.4 vs. 8.4 %; p = 0.01) and reported consistent condom use at baseline (32.9 vs. 20.9 %; p < 0.01). Partner disclosure needs to be better understood as a potential facilitator or barrier to microbicide adherence.  相似文献   
97.
BACKGROUNDGastric antral vascular ectasia (GAVE) is a significant complication of cirrhosis. Numerous medical, surgical, and endoscopic treatment modalities have been proposed with varied satisfactory results. In a few small studies, GAVE and associated anemia have resolved after orthotopic liver transplantation (OLT). AIMTo assess the impact of OLT on the resolution of GAVE and related anemia.METHODSWe retrospectively reviewed clinical records of adult patients with GAVE who underwent OLT between September 2012 and September 2019. Demographics and other relevant clinical findings were collected, including hemoglobin levels and upper endoscopy findings before and after OLT. The primary outcome was the resolution of GAVE and its related anemia after OLT.RESULTSSixteen patients were identified. Mean pre-OLT Hgb was 7.7 g/dL and mean 12 mo post-OLT Hgb was 11.9 g/dL, (P = 0.001). Anemia improved (defined as Hgb increased by 2g) in 87.5% of patients within 6 to 12 mo after OLT and resolved completely in half of the patients. Post-OLT esophagogastroduodenoscopy was performed in 10 patients, and GAVE was found to have resolved entirely in 6 of those patients (60%). CONCLUSIONAlthough GAVE and associated anemia completely resolved in the majority of our patients after OLT, GAVE persisted in a few patients after transplant. Further studies in a large group of patients are necessary to understand the causality of disease and to better understand the factors associated with the persistence of GAVE post-transplant.  相似文献   
98.
Uveitis, recurrent oral and genital ulcerations associated with skin lesions are the major symptoms of a chronic multisystemic inflammatory disorder known as Behçet’s disease (BD). High prevalence of this dreaded disease has been observed in the Mediterranean basin, including Algeria and along the Silk Road. Although the etiologic agent of this disease remains uncertain, many hypotheses have been advanced in its pathogenesis. Our team has previously reported high levels of nitric oxide (NO) in sera of BD patients, suggesting its deleterious effect during chronic inflammation. In our current study, the aim is to investigate the ex vivo immunomodulatory effect of all-trans-retinoic acid (ATRA) on NO pathway in Algerian BD patients. First, peripheral blood mononuclear cells isolated from active and inactive BD patients and healthy controls were cultured with different concentrations of ATRA. NO production was estimated with the Griess method. To elucidate the underlying mechanisms of ATRA effect on NO production, we analyze inducible nitric oxide synthase expression and nuclear factor-κB (NF-κB) activity by immunofluorescence test. Our results revealed a higher production of NO in active BD compared with the inactive stage and healthy controls. We observed that ATRA inhibits NO production in BD both in active and inactive stages and inhibits NF-κB translocation. In conclusion, we report a relationship between NO production and the disease activity. ATRA down-regulates NO production in BD patients. This immunomodulatory effect seems to be mediated through NF-κB pathway. All these findings suggest that ATRA could be considered as a promising therapy for BD.  相似文献   
99.
BACKGROUND Liver transplantation(LT) is the best treatment for patients with liver cancer or end stage cirrhosis, but it is still associated with a significant mortality. Therefore identifying factors associated with mortality could help improve patient management. The impact of iron metabolism, which could be a relevant therapeutic target, yield discrepant results in this setting. Previous studies suggest that increased serum ferritin is associated with higher mortality.Surprisingly iron deficiency which is a well described risk factor in critically ill patients has not been considered.AIM To assess the impact of pre-transplant iron metabolism parameters on posttransplant survival.METHODS From 2001 to 2011, 553 patients who underwent LT with iron metabolism parameters available at LT evaluation were included. Data were prospectively recorded at the time of evaluation and at the time of LT regarding donor and recipient. Serum ferritin(SF) and transferrin saturation(TS) were studied as continuous and categorical variable. Cox regression analysis was used to determine mortality risks factors. Follow-up data were obtained from the local and national database regarding causes of death.RESULTS At the end of a 95-mo median follow-up, 196 patients were dead, 38 of them because of infections. In multivariate analysis, overall mortality was significantly associated with TS 75% [HR: 1.73(1.14; 2.63)], SF 100 μg/L [HR: 1.62(1.12;2.35)], hepatocellular carcinoma [HR: 1.58(1.15; 2.26)], estimated glomerular filtration rate(CKD EPI Cystatin C) [HR: 0.99(0.98; 0.99)], and packed red blood cell transfusion [HR: 1.05(1.03; 1.08)]. Kaplan Meier curves show that patients with low SF( 100 μg/L) or high SF( 400 μg/L) have lower survival rates at 36 mo than patients with normal SF(P = 0.008 and P = 0.016 respectively). Patients with TS higher than 75% had higher mortality at 12 mo(91.4% ± 1.4% vs 84.6% ±3.1%, P = 0.039). TS 75% was significantly associated with infection related death [HR: 3.06(1.13; 8.23)].CONCLUSION Our results show that iron metabolism imbalance(either deficiency or overload)is associated with post-transplant overall and infectious mortality. Impact of iron supplementation or depletion should be assessed in prospective study.  相似文献   
100.
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