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11.
Franois-Xavier Briand Eric Niqueux Audrey Schmitz Claire Martenot Martine Cherbonnel Pascale Massin Florian Kerbrat Marina Chatel Carole Guillemoto Cecile Guillou-Cloarec Katell Ogor Aurlie Le Prioux Chantal Alle Vronique Beven Edouard Hirchaud Yannick Blanchard Axelle Scoizec Sophie Le Bouquin Nicolas Eterradossi Batrice Grasland 《Emerging infectious diseases》2021,27(2):508
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds. 相似文献
12.
Huimin Cheng Liangbing Fu Xia Yang Yujian Yang Zhening Zhang Yuan Tao Junting Wan Zhengchao Tu Jianxin Chen Yingjun Li 《Journal of medical virology》2023,95(1):e28327
Quinolin-2-one represents an important and valuable chemical motif that possesses a wide variety of biological activities; however, the anti-influenza activities of quinolin-2-one-containing compounds were rarely reported. Herein, we describe the screening and identification of 3-aryl-quinolin-2-one derivatives as a novel class of antiviral agents. The 3-aryl-quinolinone derivatives were synthesized via an efficient copper-catalyzed reaction cascade that we previously developed. Using this synthetic method, preliminary structure–activity relationships of this scaffold against the influenza A virus infection were systematically explored. The most potent compound 34 displayed IC50 values of 2.14 and 4.88 μM against the replication of H3N2 (A/HK/8/68) and H1N1 (A/WSN/33) strains, respectively, without apparent cytotoxicity on MDCK cells. We further demonstrated that 27 and 34 potently inhibited the plaque formation of the IAV, rendering this scaffold attractive for pursuing novel anti-influenza agents. 相似文献
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14.
TAKAHISA SAKUMA 《Pediatrics international》1997,39(6):669-675
Reports on the symptoms of infant influenza (less than 1 year of age) are very few. From 1989 to 1996, 105 infants with influenza were examined. The symptoms, nutrition and source of infection of the 105 patients were investigated in Sakuma Pediatric Clinic and viral studies were performed at the Kitakyushu City Institute of Environmental Sciences. The symptoms of patients under 6 months old are very mild, with a low maximum body temperature and a short duration of fever. Other complications are few. The symptoms gradually become more severe with each month of age. The ratio of patients displaying a diphasic fever with two peak temperatures increases with each month of age. Over 50% of patients over 9 months old have this diphasic fever with two peak temperatures. It is inconclusive whether an anti-infective factor in human milk exists or not. Of the 105 patients in this study, 28 were under 4 months of age; of these 28, all but 3 were infected by family members. 相似文献
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16.
反向点杂交快速检测流感嗜血杆菌 总被引:1,自引:0,他引:1
目的 研究以分子杂交为基础的流感嗜血杆菌 (Hi)的快速检测方法。方法 将Hi探针固定在尼龙膜上 ;用标记有地高辛的细菌通用引物聚合酶链反应 (PCR)扩增不同细菌DNA ,产物分别与点有探针的膜条杂交。结果 8种细菌均扩增出 4 6 8bp目的带 ,而人白细胞及轮状病毒DNA扩增均阴性。 6株Hi杂交阳性 ,7株其他临床常见菌杂交结果阴性。结论 反向点杂交法简便、快速、准确 ,是检测Hi的一种理想方法。 相似文献
17.
流感疫苗生产主要采用鸡胚病毒培养的方式,而提高流感病毒在鸡胚中的复制能力将能增加疫苗的产量和可靠性.影响病毒在鸡胚中繁殖的重要因素包括:流感病毒血凝素部分位点的氮基酸变异、血凝素与神经氨酸酶之间的作用平衡、病毒其他蛋白的作用及8个基因节段的重配比例.疫苗株制备方法瓶颈的突破和乙型流感病毒重配株的研究也将帮助疫苗生产商选择合适的候选疫苗株. 相似文献
18.
Mackenzie A. Hamilton Ying Liu Andrew Calzavara Maria E. Sundaram Mohamed Djebli Dariya Darvin Stefan Baral Rafal Kustra Jeffrey C. Kwong Sharmistha Mishra 《Influenza and other respiratory viruses》2022,16(6):1072
BackgroundShared and divergent predictors of clinical severity across respiratory viruses may support clinical and community responses in the context of a novel respiratory pathogen.MethodsWe conducted a retrospective cohort study to identify predictors of 30‐day all‐cause mortality following hospitalization with influenza (N = 45,749; 2010‐09 to 2019‐05), respiratory syncytial virus (RSV; N = 24 345; 2010‐09 to 2019‐04), or severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2; N = 8988; 2020‐03 to 2020‐12; pre‐vaccine) using population‐based health administrative data from Ontario, Canada. Multivariable modified Poisson regression was used to assess associations between potential predictors and mortality. We compared the direction, magnitude, and confidence intervals of risk ratios to identify shared and divergent predictors of mortality.ResultsA total of 3186 (7.0%), 697 (2.9%), and 1880 (20.9%) patients died within 30 days of hospital admission with influenza, RSV, and SARS‐CoV‐2, respectively. Shared predictors of increased mortality included older age, male sex, residence in a long‐term care home, and chronic kidney disease. Positive associations between age and mortality were largest for patients with SARS‐CoV‐2. Few comorbidities were associated with mortality among patients with SARS‐CoV‐2 as compared with those with influenza or RSV.ConclusionsOur findings may help identify patients at greatest risk of illness secondary to a respiratory virus, anticipate hospital resource needs, and prioritize local prevention and therapeutic strategies to communities with higher prevalence of risk factors. 相似文献
19.
Georgios Manessis Maciej Frant Grzegorz Wozniakowski Lapo Nannucci Martina Benedetti Lilla Denes Balka Gyula Athanasios I. Gelasakis Clare Squires Sara Recuero Carlos Sanchez Amadeu Griol Alessandro Giusti Ioannis Bossis 《Viruses》2022,14(5)
Swine viral diseases challenge the sector’s sustainability by affecting productivity and the health and welfare of the animals. The lack of antiviral drugs and/or effective vaccines renders early and reliable diagnosis the basis of viral disease management, underlining the importance of point-of-care (POC) diagnostics. A novel POC diagnostic device utilizing photonic integrated circuits (PICs), microfluidics, and information and communication technologies for the detection of porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza A (SIV) was validated using spiked and clinical oral fluid samples. Metrics including sensitivity, specificity, accuracy, precision, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to assess the performance of the device. For PRRSV, the device achieved a sensitivity of 83.5%, specificity of 77.8%, and DOR values of 17.66, whereas the values for SIV were 81.8%, 82.2%, and 20.81, respectively. The POC device and PICs can be used for the detection of PRRSV and SIV in the field, paving the way for the introduction of novel technologies in the field of animal POC diagnostics to further optimize livestock biosecurity. 相似文献
20.
返魂草提取物及其有效成分抗病毒作用的研究 总被引:9,自引:0,他引:9
目的:研究返魂草提取物及其有效成分的抗病毒作用.方法:利用鸡胚培养技术、离体和整体实验观察返魂草提取物及其有效成分对流感病毒、呼吸道合胞病毒及腺病毒的影响.结果:返魂草提取物及其有效成分(咖啡酸和绿原酸)对接种鸡胚、MDCK细胞中的流感病毒的复制具有抑制作用,可降低呼吸道合胞病毒、腺病毒感染的Hela细胞的死亡率,可降低流感病毒感染小鼠的死亡率及肺指数.结论:返魂草提取物、绿原酸咖啡酸对流感病毒、呼吸道合胞病毒及腺病毒均有抑制作用. 相似文献