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971.
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Leiying Zhang Jing Liu Enhua Wang Bing Wang Sheng Zeng Jianqi Wu Yoshinobu Kimura Beixing Liu 《Journal of medical virology》2013,85(1):149-156
Respiratory syncytial virus (RSV) infection has been hypothesized to be a risk factor for the development of allergy and asthma, but epidemiologic studies in humans still remain inconclusive. The association between RSV infection and allergic diseases may be dependent on an atopic background and previous history of RSV infection. It has been reported that RSV infection before sensitization to an allergen decreased the production of Th2‐like cytokines in the lung and the levels of allergen‐specific Th2‐type antibodies in the serum. However, the underlying mechanisms are largely unknown. In the present study, the role of pulmonary γδ T cells in RSV‐affected, allergen‐induced airway inflammation was investigated. BALB/c mice were sensitized to or challenged with ovalbumin (OVA) and infected with RSV either before or after the sensitization period. It became clear that sensitization and challenge of mice with OVA induced a large influx of γδ T cells to the lungs. However, prior RSV infection inhibited the infiltration of γδ T cells as well as activated γδ T cells, characterized by expression of CD40L or CD69 molecular in the cell surface. Moreover, prior RSV infection elevated the type 1 cytokine gene expression but suppressed type 2 cytokine expression in the lung γδ T cells. Adoptive transfer of γδ T cells from OVA‐sensitized and challenged mice increased airway inflammation, suggesting that γδ T cells may play a proinflammatory role in allergic responses. These results described here support the idea of an unknown γδ T cell‐dependent mechanism in the regulation of RSV‐affected, allergen‐induced allergic airway responses. J. Med. Virol. 85:149–156, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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Jeanne‐Marie Perotin Sandra Dury Fanny Renois Gaëtan Deslee Aurore Wolak Véronique Duval Christophe De Champs François Lebargy Laurent Andreoletti 《Journal of medical virology》2013,85(5):866-873
Few studies have evaluated the contribution of multiple virus and bacterial infections in acute exacerbation of chronic obstructive pulmonary disease. This study estimated the burden of multiple viral and bacterial respiratory infections in moderate to very severe chronic obstructive pulmonary disease patients that were prospectively followed‐up during a 12‐month pilot study. Clinical data were collected monthly and sputum was collected at the time of each acute exacerbation event. Classical culture techniques for bacteria and multiplex polymerase chain reaction (PCR) and microarray detection assays were performed to identify viral and atypical bacterial pathogens in the sputum. Overall, 51 patients were included and 45 acute exacerbation events were investigated clinically and microbiologically. Among the 45 acute exacerbation events, 44% had evidence of viral infection involving human rhinovirus (HRV) and metapneumovirus (hMPV) in 20% and 18%, respectively. Intracellular bacteria were not found in sputum by PCR. Common bacterial pathogens were identified in 42% of acute exacerbation patients, most frequently Branhamella catarrhalis, Streptococcus pneumoniae and Haemophilus influenzae. Viral or virus and bacteria co‐infections were detected in 27% of acute exacerbation events (n = 12) with HRV and hMPV involved in 92% of cases. Patients with co‐infections did not present greater clinical severity scores at exacerbation and more recurrence of acute exacerbation events at 3 and 6 months than those with single infections (P > 0.4). These results suggest that HRV and hMPV may be contributors or cofactors of AECOPD. These findings indicate that viral or virus and bacterial co‐infections do not impact significantly on the clinical severity of acute exacerbation of chronic obstructive pulmonary disease and recurrence at 3 and 6 months. J. Med. Virol. 85:866–873, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
976.
T.B. Gagliardi F.E. Paula M.A. Iwamoto J.L. Proença‐Modena A.E. Santos A.A. Camara M.C. Cervi O.A.L. Cintra E. Arruda 《Journal of medical virology》2013,85(10):1852-1859
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Anne‐Cathrine Østby Sophie Gubbels Gerben Baake Lars Peter Nielsen Casper Riedel Magnus Arpi 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(11):1097-1108
Our aim was to determine the frequency of 12 common respiratory viruses in patients admitted to intensive care units with respiratory symptoms, evaluate the clinical characteristics and to compare the results to routine microbiological diagnostics. Throat swabs from 122 intensive care‐patients >18 years with acute respiratory symptoms were collected upon admission and analysed with multiplex real‐time polymerase chain reaction, for 12 community respiratory viruses. Blood and respiratory tract specimens were analysed for bacteria and fungi upon clinicians' request. Clinical and paraclinical data were collected. Viruses were detected in 19 (16%) of the 122 study patients. Five virus‐positive patients (26%) had possible clinically relevant bacteria or fungi co‐detected. Patients with exacerbation in COPD were associated with a viral infection (p = 0.02). Other comorbidities, clinical and paraclinical parameters, and death were independent of a viral infection or co‐detection of bacteria/fungi. In conclusion, respiratory viruses were frequently detected in the patients. The investigated clinical and paraclinical parameters were not different in viral infections compared to other agents, thus respiratory viruses likely have similar impact on the clinical course as other agents. In 25% of the virus‐positive patients, polymicrobial aetiology was identified. Comprehensive and sensitive diagnostic methods should be emphasized to enhance respiratory diagnostics. 相似文献
979.
目的分析新生儿呼吸窘迫综合征(NRDS)的肺超声图像特点,以及肺超声评分(LUS)对NRDS病情评估的可行性。方法选取我院早产儿病房收治的80例NRDS患儿为观察组,根据病症严重程度分为非危重组(26例)、危重组(34例)和极危重组(20例);同时期收治的非肺部疾病的早产儿60例为对照组。分别对两组治疗前行肺部超声检查,比较两组LUS的差异,观察组治疗后72 h行超声复查,比较治疗前后LUS的差异。结果1)NRDS组肺部超声主要表现为肺实变、胸膜线异常、A线模糊或消失、胸腔积液、白肺及肺搏动减弱或消失等;2)观察组LUS明显高于对照组,差异有统计学意义(P<0.05);极危重组LUS明显高于危重组,危重组LUS明显高于非危重组,组间LUS比较差异有统计学意义(P<0.05);3)NRDS组治疗72 h后,肺实变及支气管充气征减轻,胸膜线清晰光滑,A线逐渐出现,LUS较治疗前明显减低,差异有统计学意义(P<0.05)。结论NRDS以早产儿多见,具有发病急、进展快的特点,对患儿行LUS可有效评估病情的严重程度,有重要的临床意义。 相似文献
980.