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21.
Hepatitis E virus (HEV) is the most common cause of acute liver failure (LF) and one of the most common factors causing acute injury in acute-on-chronic LF (ACLF). When HEV-related LF occurs, a series of changes take place in both the intrahepatic environment and extrahepatic microenvironment. The changed types and distribution of immune cells (infiltrating macrophages and increased lymphocytes) in liver tissue, as well the increased proinflammatory cytokines and chemokines in the blood, indicate that the occurrence and progression of HEV-related LF are closely related to immune imbalance. The clinical features and immune reaction in the body during HEV-related acute LF (ALF) and ACLF are complicated. This review highlights recent progress in elucidating the clinical manifestations of HEV-associated ALF and ACLF and discusses the corresponding systemic immune changes and possible regulatory mechanisms.  相似文献   
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目前,国内外肝移植学界对肝移植术后急性排斥反应(AR)的机制阐释为T细胞介导的细胞免疫应答,但为获得长期生存仍需长期乃至终身服用免疫抑制剂。即使如此,临床上AR仍时有发生,并导致相当一部分受者移植肝功能丧失,更重要的是受者术后还受到感染、肿瘤和其他一系列不良反应及沉重经济负担的影响。因此,为肝移植AR机制提出新的理论解释,更全面深入阐明肝移植免疫排斥反应的内在机制,进而依据新的机制研制出新型免疫抑制剂已势在必行。本文就B细胞介导的体液免疫应答在肝移植AR中的作用作一综述。  相似文献   
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6-Mercaptopurine (6-MP) is commonly used for treatment of acute lymphoblastic leukemia (ALL). The incidence of hematotoxicity caused by this drug is quite high in Asians even using a standard low dosage regimen. The present study was aimed to elucidate the impact of thiopurine S-methyltransferase (TPMT), a nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15), inosine triphosphatase (ITPA) and ATP Binding Cassette Subfamily C Member 4 (ABCC4) polymorphisms on hematotoxicity in pediatric patients who received a standard low starting dose of 6-MP. One hundred and sixty-nine pediatric patients were enrolled and their genotypes were determined. Patients who carried NUDT1513 and NUDT1512 genotypes were at a 10–15 fold higher risk of severe neutropenia than those of the wild-type during the early months of the maintenance phase. Risk of neutropenia was not significantly increased in patients with other NUDT15 variants as well as in patients with TPMT, ITPA or ABCC4 variants. These results suggest that NUDT15 polymorphisms particularly, NUDT1513 and NUDT1512, play major roles in 6-MP-induced severe hematotoxicity even when using a standard low dosage of 6-MP and genotyping of these variants is necessary in order to obtain precise tolerance doses and avoid severe hematotoxicity in pediatric patients.  相似文献   
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Background

Patients undergoing cardiac surgery are at significant risk of developing postoperative acute kidney injury (AKI). Neutrophil–lymphocyte ratio (NLR) is a widely available inflammatory biomarker which may be of prognostic value in this setting.

Methods

We conducted a systematic review and meta-analysis of studies reporting associations between perioperative NLR with postoperative AKI. We searched Medline, Embase and the Cochrane Library, without language restriction, from inception to May 2022 for relevant studies. We meta-analysed the reported odds ratios (ORs) with 95% confidence intervals (CIs) for both elevated preoperative and postoperative NLR with risk of postoperative AKI and need for renal replacement therapy (RRT). We conducted a meta-regression to explore inter-study statistical heterogeneity.

Results

Twelve studies involving 10,724 participants undergoing cardiac surgery were included, with eight studies being deemed at high risk of bias using PROBAST modelling. We found statistically significant associations between elevated preoperative NLR and postoperative AKI (OR 1.45, 95% CI 1.18–1.77), as well as postoperative need for RRT (OR 2.37, 95% CI 1.50–3.72). Postoperative NLR measurements were not of prognostic significance.

Conclusions

Elevated preoperative NLR is a reliable inflammatory biomarker for predicting AKI following cardiac surgery.  相似文献   
26.
PurposeType B aortic dissection is a rare but life-threatening disease. Thoracic endovascular aortic repair (TEVAR) was widely used for Type B aortic dissection patients in the last decade due to the lower mortality and morbidity compared with open chest surgical repair (OCSR). AKI in type B aortic dissection is a well-recognized complication and indicates poor short-term and long-term outcome. The objective of this concise review was to identify the risk factors and the impact of AKI on type B aortic dissection patients.Methods and resultsA literature search was performed using PubMed, Embase, MEDLINE, and Cochrane Library with the search terms ‘type B aortic dissection’ and ‘acute kidney injury’ (AKI), and all English-language literatures published in print or available online from inception through August 2020 were thoroughly reviewed. Studies that reported relative AKI risks and outcomes in type B aortic dissection patient were included. Major mechanisms of AKI in type B aortic dissection included renal hypoperfusion, inflammation response, and the use of contrast medium. Type B aortic dissection patients with AKI significantly had increased hospital stay duration, need of renal replacement therapy, and 30-d and 1-year mortality.ConclusionsAKI in type B aortic dissection is a well-recognized complication and associated with poor short-term and long-term outcome. Early identification of high-risk patients, early diagnosis of AKI, stabilization of the hemodynamic parameters, avoidance of nephrotoxic drugs, and optimization of the use of contrast agents are the major strategies for the reduction of AKI in type B aortic dissection patients.  相似文献   
27.
Parasitic infections of the intestine are a major health problem, which is found more prevalent in developing countries such as India. They are one of the important causes of morbidity and mortality among people all over the world. Acute amoebic appendicitis is a rare entity. We came across a case of acute appendicitis in a young pregnant woman, which revealed colonies of Entamoeba histolytica trophozoites in the mucosal epithelium and submucosal layer of the appendix with marked evidence of acute appendicitis. This report highlights acute appendicitis of amoebic origin and emphasises the importance of thorough examination of the appendix at various levels during histopathology and about the combined treatment of appendicectomy combined with antimicrobials as the treatment of choice. Appendicectomy removes the focus of infection, and antimicrobials reduce the incidence of septic complications.  相似文献   
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