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31.
PurposeWe aimed to clarify the role of particulate allergen exposure to the conjunctiva in the development of allergic conjunctivitis.MethodsWe administered ragweed pollen suspension, pollen extract, pollen shell, particulate air pollutants, and their combinations to the mouse conjunctiva five days a week without prior sensitization. Clinical signs were scored. Histological changes, cellular infiltrations, mRNA expressions, lymph node cell recall responses, and serum immunoglobulin levels were assessed. Immune cell-depleting antibodies and ST2 knockout mice were used to investigate the cellular and molecular requirements.ResultsPollen suspension, but not the extract or shell alone, induced robust eosinophilic conjunctivitis, accompanied by a proliferative response of epithelial cells. A combination of pollen extract and shell completely restored eosinophil accumulation. In addition, eosinophilic conjunctivitis was induced by a mixture of particulate air pollutants and pollen extract. Mechanistically, eosinophil accumulation was ameliorated by deficiency of the IL-33 receptor ST2 and abolished by depleting CD4+ T cells. Pollen shells, but not the extract, induced IL-33 release from conjunctival epithelial cells in vivo.ConclusionsOur results indicate the non-redundant roles for the allergens’ particulate properties and soluble factors in the development of allergic conjunctivitis.  相似文献   
32.
目的: 了解我院确诊头癣的临床特征和病原菌。方法: 对我院门诊2014年6月到2017年5月收治的头癣病例进行回顾性分析。结果: 共有35例头癣患者,其中脓癣25例 (71.4%),白癣和黑点癣各5例(14.3%)。28例患者真菌培养阳性,其中须癣毛癣菌复合体10例,断发毛癣菌7例,石膏样小孢子菌4例,犬小孢子菌3例,红色毛癣菌和紫色毛癣菌各2例。结论: 我院确诊的头癣以脓癣为主,多见于0~10岁的儿童,最常见病原菌是须癣毛癣菌复合体。  相似文献   
33.
目的:调查唐山市人民医院2005年至2009年住院肺癌患者感染条件致病性真菌的临床特点及种类,探讨条件致病性真菌感染的危险因素。方法:采用回顾性调查研究的方法,对2005年至2009年在唐山市人民医院住院并发生条件致病性真菌感染的肺癌患者进行研究。结果:住院肺癌患者送检标本的送检率和条件致病性真菌检出率均逐年增高,以念珠菌属为主,白色念珠菌是最常见的感染真菌,年龄≥60岁、住院时间长、吸烟、肿瘤恶性程度高、接受化疗及放疗、广谱抗生素和激素的大量使用、各种侵入性诊疗操作的应用等因素与肺癌患者发生条件致病性真菌感染有关。结论:控制危险因素,提高患者免疫力是预防肺癌患者条件致病性真菌感染的主要措施。  相似文献   
34.
Obstructive sleep apnea syndrome (OSAS), a chronic condition characterized by collapse of the pharynx during sleep, has been increasingly recognized as a health issue of growing importance over the last decade. Recently emerging evidence suggests that there is a causal link between OSAS and hypertension, and hypertension represents an independent risk factor in OSAS patients. However, the pathophysiological basis for patients with OSAS having an increased risk for hypertension remains to be elucidated. The main acute physiological outcomes of OSAS are intermittent hypoxia, intrapleural pressure changes, and arousal from sleep, which might induce endothelial dysfunction, sympathetic activation, renin–angiotensin–aldosterone system activation, lipid metabolism dysfunction, and increased oxidative stress. This brief review focuses on the current understanding of the complex association between OSAS and hypertension.  相似文献   
35.
Among the autoantibodies that are known to play a role in the pathogenesis or autoimmune diseases, antibodies to DNA (anti-DNA) have been the subject of much study. Several interesting observations have resulted. The ability to make antibodies that bind DNA is not abnormal. Normal mice and humans can produce antibodies that bind DNA. On the other hand, large quantities of antibodies to DNA are found in the sera of patients with systemic lupus erythematosus (SLE), and complement-lixing antibodies to double-stranded (ds) DNA cause some of the tissue lesions, especially glomerulonephritis (GN). Why, then, do some individuals make anti-DNA that deposits in glomeruli, skin, and other tissue, resulting in organ damage? It is likely that disease results from a combination of several factors— ability to make pathogenic antibody subsets, inability to downregulate those subsets, and “tissue susceptibility” to injury from those antibodies and their immune complexes. This chapter will focus on the characteristics of pathogenic antibody subsets and their regulation  相似文献   
36.
The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions.  相似文献   
37.
38.
Genetic sequences of a highly pathogenic avian influenza (H5N8) virus in England have high homology to those detected in mainland Europe and Asia during 2014. Genetic characterization suggests this virus is an avian-adapted virus without specific affinity for zoonoses. Spatio-temporal detections of H5N8 imply a role for wild birds in virus spread.  相似文献   
39.
《Islets》2013,5(4)
The disease mechanisms underlying type 2 diabetes (T2D) remain poorly defined. Here we aimed to explore the pathophysiology of T2D by analyzing gene co-expression networks in human islets. Using partial correlation networks we identified a group of co-expressed genes (‘module’) including F2RL2 that was associated with glycated hemoglobin. F2Rl2 is a G-protein-coupled receptor (GPCR) that encodes protease-activated receptor-3 (PAR3). PAR3 is cleaved by thrombin, which exposes a 6-amino acid sequence that acts as a ‘tethered ligand’ to regulate cellular signaling. We have characterized the effect of PAR3 activation on insulin secretion by static insulin secretion measurements, capacitance measurements, studies of diabetic animal models and patient samples. We demonstrate that thrombin stimulates insulin secretion, an effect that was prevented by an antibody that blocks the thrombin cleavage site of PAR3. Treatment with a peptide corresponding to the PAR3 tethered ligand stimulated islet insulin secretion and single β-cell exocytosis by a mechanism that involves activation of phospholipase C and Ca2+ release from intracellular stores. Moreover, we observed that the expression of tissue factor, which regulates thrombin generation, was increased in human islets from T2D donors and associated with enhanced β-cell exocytosis. Finally, we demonstrate that thrombin generation potential in patients with T2D was associated with increased fasting insulin and insulinogenic index. The findings provide a previously unrecognized link between hypercoagulability and hyperinsulinemia and suggest that reducing thrombin activity or blocking PAR3 cleavage could potentially counteract the exaggerated insulin secretion that drives insulin resistance and β-cell exhaustion in T2D.  相似文献   
40.
杨一博  刘民 《疾病监测》2011,26(4):328-333
目的 认识人禽流感的临床特征,为人感染H5N1型高致病性禽流感的症状监测和疾病监测的完善提供循证依据。 方法 以规定检索词在常用中、英文数据库中检索并严格按照纳入排除标准纳入文献。将纳入文献的研究病例汇集后分析其症状、体征、常见实验室检查、影像学改变及其并发症等临床特征发生的概率。 结果 经过严格筛选共纳入文献32篇,其中中文文献11篇,英文文献21篇,汇集研究病例236例。质量评价得分中位数为31分,53.1%的文献质量评价得分30分。人禽流感的症状及体征主要为发热(体温38 ℃)、咳嗽、呼吸频率增快和呼吸困难,实验室检查主要为外周血白细胞数和淋巴细胞绝对数的减少,影像学改变以浸润、实变等肺炎改变为主,重症人禽流感患者最易出现的并发症为急性呼吸窘迫综合征。 结论 加强临床医生对人禽流感患者非呼吸系统的临床表现的认识,可提高对禽流感病例早期筛查的准确性。  相似文献   
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