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991.
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Rodrigo Pess?a Jaqueline Tomoko Watanabe Paula Calabria Alvina Clara Felix Paula Loureiro Ester C. Sabino Michael P. Busch Sabri S. Sanabani for the International Component of the NHLBI Recipient Epidemiology Donor Evaluation Study-III 《PloS one》2014,9(11)
Background
The findings of frequent circulation of HIV-1 subclade F1 viruses and the scarcity of BF1 recombinant viruses based on pol subgenomic fragment sequencing among blood donors in Pernambuco (PE), Northeast of Brazil, were reported recently. Here, we aimed to determine whether the classification of these strains (n = 26) extends to the whole genome sequences.Methods
Five overlapping amplicons spanning the HIV near full-length genomes (NFLGs) were PCR amplified from peripheral blood mononuclear cells (PBMCs) of 26 blood donors. The amplicons were molecularly bar-coded, pooled, and sequenced by Illumina paired-end protocol. The prevalence of viral variants containing drug resistant mutations (DRMs) was compared between plasma and PBMCs.Results
Of the 26 samples studied, 20 NFLGs and 4 partial fragments were de novo assembled into contiguous sequences and successfully subtyped. Two distinct BF1 recombinant profiles designated CRF70_BF1 and CRF71_BF1, with 4 samples in profile I and 11 in profile II were detected and thus constitute two novel recombinant forms circulating in PE. Evidence of dual infections was detected in four patients co-infected with distinct HIV-1 subtypes. According to our estimate, the new CRF71_BF1 accounts for 10% of the HIV-1 circulating strains among blood donors in PE. Discordant data between the plasma and PBMCs-virus were found in 15 of 24 donors. Six of these strains displayed major DRMs only in PBMCs and four of which had detectable DRMs changes at prevalence between 1-20% of the sequenced population.Conclusions
The high percentage of the new RF71_BF1 and other BF1 recombinants found among blood donors in Pernambuco, coupled with high rates of transmitted DRMs and dual infections confirm the need for effective surveillance to monitor the prevalence and distribution of HIV variants in a variety of settings in Brazil. 相似文献993.
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Rongbao Gao Jingdong Song Ye Zhang Shumei Zou Tian Bai Xiaodan Li Jianguo Qu Jianfang Zhou Tao Hung 《Virologica Sinica》2014,(2):119-122
正Dear Editor,In March 2013,the first 3 cases of severe disease dueto a novel avian-origin influenza A(H7N9)virus weredetected in the Chinese provinces of Shanghai and Anhui(Gao R,et al.,2013).A total of 339 laboratory-confirmedcases with 100 deaths were reported until January 142014(WHO,2014).To the best of our knowledge,thisis the first time that human infection with the avian in-fluenza A H7N9 subtype has been detected.Prior to this 相似文献
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Yagahira E. Castro-Sesquen Robert H. Gilman Gerson Galdos-Cardenas Lisbeth Ferrufino Gerardo Sánchez Edward Valencia Ayala Lance Liotta Caryn Bern Alessandra Luchini the Working Group on Chagas Disease in Bolivia Peru 《PLoS neglected tropical diseases》2014,8(10)
Background
Detection of congenital T. cruzi transmission is considered one of the pillars of control programs of Chagas disease. Congenital transmission accounts for 25% of new infections with an estimated 15,000 infected infants per year. Current programs to detect congenital Chagas disease in Latin America utilize microscopy early in life and serology after 6 months. These programs suffer from low sensitivity by microscopy and high loss to follow-up later in infancy. We developed a Chagas urine nanoparticle test (Chunap) to concentrate, preserve and detect T. cruzi antigens in urine for early, non-invasive diagnosis of congenital Chagas disease.Methodology/Principal Findings
This is a proof-of-concept study of Chunap for the early diagnosis of congenital Chagas disease. Poly N-isopropylacrylamide nano-particles functionalized with trypan blue were synthesized by precipitation polymerization and characterized with photon correlation spectroscopy. We evaluated the ability of the nanoparticles to capture, concentrate and preserve T. cruzi antigens. Urine samples from congenitally infected and uninfected infants were then concentrated using these nanoparticles. The antigens were eluted and detected by Western Blot using a monoclonal antibody against T. cruzi lipophosphoglycan. The nanoparticles concentrate T. cruzi antigens by 100 fold (western blot detection limit decreased from 50 ng/ml to 0.5 ng/ml). The sensitivity of Chunap in a single specimen at one month of age was 91.3% (21/23, 95% CI: 71.92%–98.68%), comparable to PCR in two specimens at 0 and 1 month (91.3%) and significantly higher than microscopy in two specimens (34.8%, 95% CI: 16.42%–57.26%). Chunap specificity was 96.5% (71/74 endemic, 12/12 non-endemic specimens). Particle-sequestered T. cruzi antigens were protected from trypsin digestion.Conclusion/Significance
Chunap has the potential to be developed into a simple and sensitive test for the early diagnosis of congenital Chagas disease. 相似文献999.
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