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Mitsuhiro Yamada 《Respiratory investigation》2021,59(3):302-311
Alveoli are the basic structure of the lungs, consisting of various types of parenchymal and bone marrow-derived cells including alveolar macrophages. These various types of cells have several important functions; thus, communication between these cells plays an important role in homeostasis as well as in the pathophysiology of diseases in the lungs. For a better understanding of the pathophysiology of lung diseases, researchers have isolated each type of lung cell to investigate the changes in their gene expressions, including their humoral factor or adhesion molecules, to reveal the intercellular communication among these cells. In particular, investigations during the past decade have focused on extracellular vesicles, which are lipid bilayer delimited vesicles released from a cell that can move among various cells and transfer substances, including microRNAs, mRNAs and proteins, thus, functioning as intercellular messengers. Extracellular vesicles can be classified into three general groups: apoptotic bodies, exosomes, and microparticles. Extracellular vesicles, especially exosomes and microparticles, are attracting increasing attention from pulmonologists as tools for understanding pathogenesis and disease diagnosis. Here, we review studies, including our own, on exosomes and microparticles and their roles in both lung homeostasis and the pathogenesis of lung diseases such as idiopathic pulmonary fibrosis, chronic obstructive lung diseases, and acute respiratory distress syndrome. This review also addresses the roles of extracellular vesicles in COVID-19, the current global public health crisis. 相似文献
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患者男,39岁,面部皮肤肥厚、四肢肢端肥大20年,间断头晕乏力1年。查体:重度贫血貌,睑结膜、口唇及甲床苍白;头面部皮肤肥厚、皱褶、呈回状颅皮;双下肢皮肤肥厚,手指及足趾呈杵状;皮损颜色正常,触之略韧;踝关节肿胀无压痛、活动自如。X线检查提示右腓骨中段髓腔密度增多,腓骨中段及胫骨下段后缘骨皮质增厚。血常规重度正常细胞低色素性贫血,骨髓活检提示骨髓造血衰竭,骨髓纤维化不明显。诊断:原发性骨膜增生厚皮症伴重度贫血。 相似文献
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Co-trimoxazole is mainly used as a first-line drug for treatment and prophylaxis against Pneumocystis jiroveci pneumonia. This drug, however, has been reported as the most common causative drug for severe cutaneous adverse reactions (SCARs). This study aimed to extensively elucidate the associations between genetic polymorphisms of HLA class I and genes involved in bioactivation and detoxification of co-trimoxazole on co-trimoxazole-induced SCARS in a large sample size and well-defined Thai SCARs patients. A total of 67 patients with co-trimoxazole-induced SCARs, consisting of 51 SJS/TEN patients and 16 DRESS patients, and 91 co-trimoxazole tolerant controls were enrolled in the study. The results clearly demonstrated that the HLA-B113:01 allele was significantly associated with co-trimoxazole-induced SCARs, especially with DRESS (OR = 8.44, 95% CI = 2.66–26.77, P = 2.94 × 10−4, Pc = 0.0126). Moreover, the HLA-C108:01 allele was significantly associated with co-trimoxazole-induced SJS/TEN in the HIV/AIDS patients with an OR of 8.51 (95% CI = 2.18–33.14, P = 8.60 × 10−4, Pc = 0.0241). None of the genes involved in the bioactivation and detoxification of co-trimoxazole investigated in this study play any major role in the development of all phenotypes of SCARs. 相似文献
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《Human immunology》2022,83(12):803-807
We examined the correlation between class I HLA evolutionary divergence (HED), a surrogate for the capacity to present different peptides, and the outcomes of 234 adult inpatients with confirmed SARS-CoV-2 infection. Genomic DNA was extracted from peripheral blood and genotyped by next-generation sequencing (NGS). HED scores for HLA class I (HLA-A, -B, and -C) genotypes were calculated using Grantham’s distance. Higher HED scores for HLA-B, but not HLA-A or -C, are significantly associated with a decreased probability of poor outcomes including ICU admission, mechanical ventilation, and death (OR = 0.93; P = 0.04) in the univariate analysis. In the multivariate analysis, increased HLA-B HED score, younger age, and no comorbidity were independently associated with favorable outcomes (P = 0.02, P = 0.01, and P = 0.05, respectively). This finding is consistent with the notion that broader peptide repertoires presented by class I HLA may be beneficial in infection control. 相似文献
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Wattana Leowattana Tawithep Leowattana Pathomthep Leowattana 《World Journal of Clinical Cases》2022,10(34):12470-12483
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a widespread outbreak since December 2019. The SARS-CoV-2 infection-related illness has been dubbed the coronavirus disease 2019 (COVID-19) by the World Health Organization. Asymptomatic and subclinical infections, a severe hyper-inflammatory state, and mortality are all examples of clinical signs. After attaching to the angiotensin converting enzyme 2 (ACE2) receptor, the SARS-CoV-2 virus can enter cells through membrane fusion and endocytosis. In addition to enabling viruses to cling to target cells, the connection between the spike protein (S-protein) of SARS-CoV-2 and ACE2 may potentially impair the functionality of ACE2. Blood pressure is controlled by ACE2, which catalyzes the hydrolysis of the active vasoconstrictor octapeptide angiotensin (Ang) II to the heptapeptide Ang-(1-7) and free L-Phe. Additionally, Ang I can be broken down by ACE2 into Ang-(1-9) and metabolized into Ang-(1-7). Numerous studies have demonstrated that circulating ACE2 (cACE2) and Ang-(1-7) have the ability to restore myocardial damage in a variety of cardiovascular diseases and have anti-inflammatory, antioxidant, anti-apoptotic, and anti-cardiomyocyte fibrosis actions. There have been some suggestions for raising ACE2 expression in COVID-19 patients, which might be used as a target for the creation of novel treatment therapies. With regard to this, SARS-CoV-2 is neutralized by soluble recombinant human ACE2 (hrsACE2), which binds the viral S-protein and reduces damage to a variety of organs, including the heart, kidneys, and lungs, by lowering Ang II concentrations and enhancing conversion to Ang-(1-7). This review aims to investigate how the presence of SARS-CoV-2 and cACE2 are related. Additionally, there will be discussion of a number of potential therapeutic approaches to tip the ACE/ACE-2 balance in favor of the ACE-2/Ang-(1-7) axis. 相似文献
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目的分析重症肺炎并呼吸衰竭患儿接受早期持续气道正压通气(CPAP)治疗对血气指标及预后的影响。方法选取2019年2月至2020年6月本院收治的110例重症肺炎并呼吸衰竭患儿,按照组间基本资料具有可比性的原则分为对照组与实验组,各55例。对照组接受常规方案治疗,实验组接受早期持续CPAP治疗,比较两组血气指标改善情况以及患儿预后。结果治疗后,两组PaO2、PaCO2、SaO2均显著改善,且实验组改善程度明显优于对照组(P<0.05)。实验组临床病死率明显低于对照组(P<0.05)。两组并发症发生率比较差异无统计学意义。结论采用早期持续CPAP治疗重症肺炎并呼吸衰竭患儿效果显著,能明显改善血气指标和预后,具有临床推广价值。 相似文献
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《Journal of pediatric surgery》2023,58(4):613-618
PurposeThe purpose of this study was to analyze the management and outcomes of primary button battery ingestions and their sequelae at a single high-volume center, and to propose a risk score to predict the likelihood of a severe outcome.MethodsThe medical record was queried for all patients under 21 years old evaluated at our institution for button battery ingestion from 2008 to 2021. A severe outcome was defined as having at least one of the following: deep/circumferential mucosal erosion, perforation, mediastinitis, vascular or airway injury/fistula, or development of esophageal stricture. From a selection of clinically relevant factors, logistic regression determined predictors of a severe outcome, which were incorporated into a risk model.Results143 patients evaluated for button battery ingestion were analyzed. 24 (17%) had a severe outcome. The independent predictors of a severe outcome in multivariate analysis were location of battery in the esophagus on imaging (96%), battery size >/ = 2 cm (95%), and presence of any symptoms on presentation (96%), with P < 0.001 in all cases. Predicted probability of a severe outcome ranged from 88% when all three risk factors were observed, to 0.3% when none were present.ConclusionWe report the presentation, management, and complication profiles of a large cohort of BB ingestions treated at a single institution. A risk score to predict severe outcomes may be used by providers initially evaluating patients with button battery ingestion in order to allocate resources and expedite transfer to a center with pediatric endoscopic and surgical capabilities.Level of evidenceLevel IV.Type of studyClinical Research Paper. 相似文献