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Are we ready for pandemic influenza?   总被引:1,自引:0,他引:1  
During the past year, the public has become keenly aware of the threat of emerging infectious diseases with the global spread of severe acute respiratory syndrome (SARS), the continuing threat of bioterrorism, the proliferation of West Nile virus, and the discovery of human cases of monkeypox in the United States. At the same time, an old foe has again raised its head, reminding us that our worst nightmare may not be a new one. In 2003, highly pathogenic strains of avian influenza virus, including the H5N1 and H7N7 subtypes, again crossed from birds to humans and caused fatal disease. Direct avian-to-human influenza transmission was unknown before 1997. Have we responded to these threats by better preparing for emerging disease agents, or are we continuing to act only as crises arise? Here we consider progress to date in preparedness for an influenza pandemic and review what remains to be done. We conclude by prioritizing the remaining needs and exploring the reasons for our current lack of preparedness for an influenza pandemic.  相似文献   
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Very few, mostly old, and only preliminary serological studies of brucellosis in goats exist in Ecuador. In order to assess the current epidemiological situation, we performed a cross-sectional serological study in the goat populations of Carchi (n?=?160 animals), Pichincha (n?=?224 animals), and Loja provinces (n?=?2024 animals). Only two positive serological results (RB negative and SAT-EDTA ≥400 IU/ml) were obtained in lactating goats from the same farm in Quito (Pichincha province). Additionally, milk was sampled from 220 animals in Pichincha province. The present study indicates a low apparent prevalence in Pichincha province and absence in Carchi and Loja provinces. A total of 25 positive milk ring tests (MRT) were obtained in Pichincha province yielding a prevalence of MRT of 11.16%. Subsequent culture was performed on the positive MRT samples. All results were negative, apart from a single sample, obtained from a serologically positive goat in Quito, that was positive for Brucella abortus strain 19 (B19). Several hypotheses are forwarded concerning this unexpected result. The most likely hypothesis is the possible accidental use of a needle, previously used for vaccination of cattle with the said vaccine, for the administration of drug treatment to the goat. This hypothesis underlines the necessity of biosecurity measures to prevent this type of accidents.  相似文献   
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Variants in the FTO (fat mass and obesity associated) gene are associated with increased body mass index in humans. Here, we show by bioinformatics analysis that FTO shares sequence motifs with Fe(II)- and 2-oxoglutarate-dependent oxygenases. We find that recombinant murine Fto catalyzes the Fe(II)- and 2OG-dependent demethylation of 3-methylthymine in single-stranded DNA, with concomitant production of succinate, formaldehyde, and carbon dioxide. Consistent with a potential role in nucleic acid demethylation, Fto localizes to the nucleus in transfected cells. Studies of wild-type mice indicate that Fto messenger RNA (mRNA) is most abundant in the brain, particularly in hypothalamic nuclei governing energy balance, and that Fto mRNA levels in the arcuate nucleus are regulated by feeding and fasting. Studies can now be directed toward determining the physiologically relevant FTO substrate and how nucleic acid methylation status is linked to increased fat mass.  相似文献   
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来自香港和世界各地的10株宠物鸟H3N8流感病毒的HA基因进行了全基因序列测定,用DNASTAR和Tree-View软件进行序列编辑,序列翻译,进化树绘制和分子演化分析.结果表明来自不同国家和地区的H3N8流感病毒的HA基因都非常相似,都形成一个独立的分支,属于欧亚亚系,同源率为95.9%~100%;香港2001年宠物鸟的毒株之间的同源率最高,分别为99.2%~100%.HA基因与A/Equine/Jilin/89(H3N8)的同源性为最高,在92.9%~93.6%之间.氨基酸分析表明只有A/Parakeet/Netherland/33/01的HA基因在97~99受体结合位点处有一个额外潜在的糖基化位点NKT;因此可见宠物鸟H3N8流感病毒的HA基因高度保守,HA基因均来自共同的祖先.  相似文献   
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Bee-collected pollen ("bee pollen") is promoted as a health food with a wide range of nutritional and therapeutic properties. The objective of the current study is to evaluate the contribution made through the free radical scavenging capability of bee-collected floval pollens by their flavonoid/phenolics constituents, and to determine whether this capability is affected by aging. The free radical scavenging effectiveness of a bee pollen (EC(50)) as measured by the DPPH method is shown to be determined by the nature and levels of the constituent floral pollens, which can be assayed via their phenolics profiles by HPLC. Each pure floral pollen has been found to possess a consistent EC(50) value, irrespective of its geographic origin or date of collection, and the EC(50) value is determined to a large extent (ca. 50%) by the nature and the levels of the pollen's flavonoids and phenolic acids. Non-phenolic antioxidants, possibly proteins, account for the balance of the activity. Pollen aging over 3 years is demonstrated to reduce the free radical scavenging activity by up to 50% in the most active floral pollens, which tend to contain the highest levels of flavonoids/phenolic acids. It is suggested that the freshness of a bee pollen may be determined from its free radical scavenging capacity relative to that of fresh bee pollen containing the same floral pollen mix.  相似文献   
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为明确球刺盘孢Colletotrichum coccodes产生的细胞壁降解酶(CWDEs)在其侵染马铃薯过程中的作用, 本文对球刺盘孢离体和活体条件下产生的CWDEs种类及活性进行检测, 并通过RT-qPCR测定了球刺盘孢侵染过程中多聚半乳糖醛酸酶(PG)基因的表达情况。通过定性测定发现, 球刺盘孢能够产生果胶酶、纤维素酶和蛋白酶; 定量测定发现, 球刺盘孢可产生羧甲基纤维素酶(Cx)、β-葡萄糖苷酶(β-Glu)、PG和聚甲基半乳糖醛酸酶(PMG)。在活体条件下, 球刺盘孢可在马铃薯茎秆内产生PG、PMG和多聚半乳糖醛酸反式消除酶(PGTE), 且酶活分别于接种后48、72 h和144 h达到最大值, 分别为26.50、77.61 U/mL和0.16 U/mg。分别将羧甲基纤维素钠和果胶诱导后的酶液接种至马铃薯茎秆可引起植物组织浸腐, 与球刺盘孢引起的典型症状相似。除此之外, 球刺盘孢的4个PGs基因均在其侵染后24 h和48 h显著共上调表达。综上所述, 该研究结果表明, 果胶酶在球刺盘孢致病过程中发挥重要作用。  相似文献   
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Pigs and humans have shared influenza A viruses (IAV) since at least 1918, and many interspecies transmission events have been documented since that time. However, despite this interplay, relatively little is known regarding IAV circulating in swine around the world compared with the avian and human knowledge base. This gap in knowledge impedes our understanding of how viruses adapted to swine or man impacts the ecology and evolution of IAV as a whole and the true impact of swine IAV on human health. The pandemic H1N1 that emerged in 2009 underscored the need for greater surveillance and sharing of data on IAV in swine. In this paper, we review the current state of IAV in swine around the world, highlight the collaboration between international organizations and a network of laboratories engaged in human and animal IAV surveillance and research, and emphasize the need to increase information in high‐priority regions. The need for global integration and rapid sharing of data and resources to fight IAV in swine and other animal species is apparent, but this effort requires grassroots support from governments, practicing veterinarians and the swine industry and, ultimately, requires significant increases in funding and infrastructure.  相似文献   
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