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BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.  相似文献   
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BackgroundStenotrophomonas maltophilia, a species of highly genetic diversity, has emerged as an important nosocomial pathogen. S. maltophilia and Pseudomonas aeruginosa are often co-isolated from pneumonia patients. In our previous study, we have demonstrated that the pacIRA cluster present in some but not all clinical S. maltophilia isolates. Proteins encoded by pacIRA operon are an extracytoplasmic function (ECF) sigma factor, a transmembrane anti-sigma regulator, and a TonB-dependent receptor. This study aimed to elucidate PacIRA system function and its significance to S. maltophilia.MethodsThe pacI, pacR, and pacA genes were individually or totally deleted from the chromosome of KJΔEnt, a pacIRA-positive and siderophore-null strain. Growth promotion assay was performed to examine the implication of pacIRA system in iron utilization. Gene expression was quantified by quantitative real time PCR (qRT-PCR). Growth competition assay was executed to investigate the significance of pacIRA operon to S. maltophilia.ResultsPacIRA system contributed to utilize ferri-pyochelin of P. aeruginosa as iron sources for growth in an iron-depleted condition, but hardly utilized ferric citrate, hemin, ferri-stenobactin, and ferri-pyoverdine. PacIRA was founded to belong to Fur regulon and upregulated in response to iron-depleted stress. Growth competition assay demonstrated that pacIRA-positive S. maltophilia had a superiority over pacIRA-negative S. maltophilia in iron acquisition when they were co-cultured in P. aeruginosa ferri-pyochelin-supplemented medium.ConclusionsPacIRA system of S. maltophilia is a xenosiderophore uptake implement, involving in the acquisition of pyochelin of P. aeruginosa.  相似文献   
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Whether the underlying mutations are homozygous, heterozygous, or co-inherited with other hemoglobinopathies, sickle cell disease is known to afflict the kidneys, leading to the clinical entity known as sickle cell nephropathy (SCN). Although common, SCN remains diagnostically elusive. Conventional studies performed in the context of renal disorders often fail to detect early stage SCN. This makes the quest for early diagnosis and treatment more challenging, and it increases the burden of chronic kidney disease-related morbidity among patients. Novel diagnostic tools have been employed to overcome this limitation. In this study, we discuss various biomarkers of SCN, including those employed in clinical practice and others recently identified in experimental settings, such as markers of vascular injury, endothelial dysfunction, tubulo-glomerular damage, and oxidative stress. These include kidney injury molecule-1, monocyte chemoattractant protein-1, N-acetyl-B-D-glucosaminidase, ceruloplasmin, orosomucoid, nephrin, and cation channels, among others. Furthermore, we explore the potential of novel biomarkers for refining diagnostic and therapeutic approaches and describe some obstacles that still need to be overcome. We highlight the importance of a collaborative approach to standardize the use of promising new biomarkers. Finally, we outline the limitations of conventional markers of renal damage as extensions of the pathogenic process occurring at the level of the organ and its functional subunits, with a discussion of the expected pattern of clinical and biochemical progression among patients with SCN.  相似文献   
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BackgroundGastrointestinal stromal tumors have been detected in 25% of the necropsies performed on NF1 patients, but have been reported only in 7% of NF1 patients in the largest series. Such data imply an important gap between the true presence of tumors and those diagnosed. Few genotype-phenotype relationships have been described but to date none referring to abdominal tumors.ObjectivesEvaluate retrospectively the efficacy of a regular and proactive follow-up of NF1 patients to early diagnose abdominal tumors and report their mutations.MethodsCohort study performed between 2010 and 2020, with 43 NF1 adult patients followed at our Dermatology department.ResultsEight abdominal tumors were diagnosed in six patients, meaning that 14% of the followed patients developed an abdominal tumor. Five patients (83%) were asymptomatic. Five (83.3%) had a family history of NF1 with abdominal tumors (patients 1,2 and 3,4,5 were relatives).ConclusionsAlthough currently gastrointestinal routine screening investigations for asymptomatic patients are not recommended in the guidelines, the family aggregation in our series suggests it should be considered a close follow-up of the relatives of a patient with an NF1-related abdominal tumor. Also, for the first time, two mutations [c.2041C > T (p.Arg681Ter) and c.4537C > T (p.Arg1513*)] have been associated with family aggregation of abdominal tumors in NF1 patients.  相似文献   
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