1,120 research outputs found
Genomic Inference of the Metabolism and Evolution of the Archaeal Phylum Aigarchaeota
Microbes of the phylum Aigarchaeota are widely distributed in geothermal environments, but their physiological and ecological roles are poorly understood. Here we analyze six Aigarchaeota metagenomic bins from two circumneutral hot springs in Tengchong, China, to reveal that they are either strict or facultative anaerobes, and most are chemolithotrophs that can perform sulfide oxidation. Applying comparative genomics to the Thaumarchaeota and Aigarchaeota, we find that they both originated from thermal habitats, sharing 1154 genes with their common ancestor. Horizontal gene transfer played a crucial role in shaping genetic diversity of Aigarchaeota and led to functional partitioning and ecological divergence among sympatric microbes, as several key functional innovations were endowed by Bacteria, including dissimilatory sulfite reduction and possibly carbon monoxide oxidation. Our study expands our knowledge of the possible ecological roles of the Aigarchaeota and clarifies their evolutionary relationship to their sister lineage Thaumarchaeota
Cross-sectional study of the relationship of peripheral blood cell profiles with severity of infection by adenovirus type 55
BACKGROUND: The immunologic profiles of patients with human adenovirus serotype 55 (HAdV-55) infections were characterized in subjects diagnosed with silent infections (n = 30), minor infections (n = 27), severe infections (n = 34), and healthy controls (n = 30) during a recent outbreak among Chinese military trainees. METHODS: Blood was sampled at the disease peak and four weeks later, and samples were analyzed to measure changes in leukocyte and platelet profiles in patients with different severities of disease. Differential lymphocyte subsets and cytokine profiles were measured by flow cytometry and Luminex xMAP®, and serum antibodies were analyzed by ELISA and immunofluorescence staining. RESULTS: Patients with severe HAdV infections had higher proportions of neutrophils and reduced levels of lymphocytes (p < 0.005 for both). Patients with minor and severe infections had significantly lower platelet counts (p < 0.005 for both) than those with silent infections. The silent and minor infection groups had higher levels of dendritic cells than the severe infection group. Relative to patients with silent infections, patients with severe infections had significantly higher levels of IL-17(+)CD4(+) cells, decreased levels of IL-17(+)CD8(+) cells, and higher levels of IFN-γ, IL-4, IL-10, and IFN-α2 (p < 0.001 for all comparisons). CONCLUSIONS: Patients with different severities of disease due to HAdV-55 infection had significantly different immune responses. These data provide an initial step toward the identification of patients at risk for more severe disease and the development of treatments against HAdV-55 infection
MYH9 is an Essential Factor for Porcine Reproductive and Respiratory Syndrome Virus Infection
Porcine reproductive and respiratory syndrome (PRRS) caused by the PRRS virus (PRRSV) is an important swine disease worldwide. PRRSV has a limited tropism for certain cells, which may at least in part be attributed to the expression of the necessary cellular molecules serving as the virus receptors or factors on host cells for virus binding or entry. However, these molecules conferring PRRSV infection have not been fully characterized. Here we show the identification of non-muscle myosin heavy chain 9 (MYH9) as an essential factor for PRRSV infection using the anti-idiotypic antibody specific to the PRRSV glycoprotein GP5. MYH9 physically interacts with the PRRSV GP5 protein via its C-terminal domain and confers susceptibility of cells to PRRSV infection. These findings indicate that MYH9 is an essential factor for PRRSV infection and provide new insights into PRRSV-host interactions and viral entry, potentially facilitating development of control strategies for this important swine disease
A novel porcine reproductive and respiratory syndrome virus vector system that stably expresses enhanced green fluorescent protein as a separate transcription unit
Abstract Here we report the rescue of a recombinant porcine reproductive and respiratory syndrome virus (PRRSV) carrying an enhanced green fluorescent protein (EGFP) reporter gene as a separate transcription unit. A copy of the transcription regulatory sequence for ORF6 (TRS6) was inserted between the N protein and 3′-UTR to drive the transcription of the EGFP gene and yield a general purpose expression vector. Successful recovery of PRRSV was obtained using an RNA polymerase II promoter to drive transcription of the full-length virus genome, which was assembled in a bacterial artificial chromosome (BAC). The recombinant virus showed growth replication characteristics similar to those of the wild-type virus in the infected cells. In addition, the recombinant virus stably expressed EGFP for at least 10 passages. EGFP expression was detected at approximately 10 h post infection by live-cell imaging to follow the virus spread in real time and the infection of neighbouring cells occurred predominantly through cell-to-cell-contact. Finally, the recombinant virus generated was found to be an excellent tool for neutralising antibodies and antiviral compound screening. The newly established reverse genetics system for PRRSV could be a useful tool not only to monitor virus spread and screen for neutralising antibodies and antiviral compounds, but also for fundamental research on the biology of the virus.This study was funded by grants from the National Natural Science Foundation of China (U0931003/L01) and the National High-Tech R&D Program of China (2011AA10A208) to EMZ, the National Natural Science Foundation of China (31302103) to WCB, the European Community’s Seventh Frame-work Programme (PoRRSCon, FP7-KBBE-2009-3-245141) and the Ministry of Science and Innovation of Spain (MCINN) (BIO2010-16075) to FA and LE.Peer Reviewe
Three-dimensional femtosecond laser nanolithography of crystals
Nanostructuring hard optical crystals has so far been exclusively feasible at
their surface, as stress induced crack formation and propagation has rendered
high precision volume processes ineffective. We show that the inner chemical
etching reactivity of a crystal can be enhanced at the nanoscale by more than
five orders of magnitude by means of direct laser writing. The process allows
to produce cm-scale arbitrary three-dimensional nanostructures with 100 nm
feature sizes inside large crystals in absence of brittle fracture. To showcase
the unique potential of the technique, we fabricate photonic structures such as
sub-wavelength diffraction gratings and nanostructured optical waveguides
capable of sustaining sub-wavelength propagating modes inside yttrium aluminum
garnet crystals. This technique could enable the transfer of concepts from
nanophotonics to the fields of solid state lasers and crystal optics.Comment: Submitted Manuscript and Supplementary Informatio
بررسی حیطههای موجود در فرمهای ارزشیابی از دیدگاه دانشجویان در دانشگاه علوم پزشکی زنجان در سال تحصیلی 86- 87
زمینه و هدف: ارزشیابی استادان متداولترین روش جهت سنجش کیفیت آموزش میباشد. دانشجویان بیش از دستاندرکاران در جریان روند آموزش قراردارند بنابراین با نظرخواهی از آنان دیدگاه کاملی برای مسئولین در مورد نقاط قوت و ضعف استادان بهدست میآید. هدف از این پژوهش بررسی حیطههای موجود در فرمهای ارزشیابی از دیدگاه دانشجویان در دانشکدههای پزشکی، پیراپزشکی و پرستاری و مامایی میباشد.
روش بررسی: این تحقیق به صورت توصیفی انجام گرفت. 1683 برگ ارزشیابی دانشجویان از استادان هیأت علمی (73 نفر) مربوط به دانشکدههای پزشکی، پیراپزشکی و پرستاری- مامایی بررسی شد. پرسشنامهی دانشجویان پزشکی حاوی 15 سؤوال و دانشجویان پیراپزشکی و پرستاری مامایی
21 سؤوال بود که بر اساس مقیاس لیکرات از حیطههای مختلف مقرراتی، علمی و آموزشی، نظارتی و نگرشی تشکیل شده بود. نمرات سؤوالات از نمرهی 100 محاسبه شد، نمرات بالاتر بیانگر عملکرد مطلوبتراستادان میباشد. تجزیه و تحلیل دادهها بهصورت آمار توصیفی با نرمافزار SPSS
انجام شد.
یافتهها: نتایج نشان داد مقایسه در سطوح کلی بین دانشکدهها، دانشکدهی پیراپزشکی با میانگین کل و انحراف معیار 61/3 ±50/85 نسبت به سایر دانشکدهها برتری دارد. دانشکدهی پیراپزشکی در حیطهی مقرراتی با میانگین و انحراف معیار 89/3±01/91، دانشکدهی پزشکی در حیطهی نگرشی با میانگین و انحراف معیار 45/5±48/90 و دانشکدهی پرستاری مامایی در حیطهی مقرراتی با میانگین و انحراف معیار 25/4±34/88 بیشترین امتیاز را داشتند. نتیجهنهایی نشان میدهد، حیطهی علمی و آموزشی نسبت به سایر حیطهها در سطح پایینتر میباشد. نتایج حیطهها (علمی و آموزشی، نظارتی و نگرشی) بین دانشکدهها معنیدار میباشد (0001/0=P).
نتیجهگیری: به نظر میرسد با برنامهریزی جهت برگزاری کارگاههای آموزشی، روش تدریس و تحقیق جهت ارتقای آموزش استادان، اعطای فرصت مطالعاتی و تشویق انجام کارهای تحقیقاتی و پژوهشی گام مؤثری جهت ارتقای سطح علمی و بالاخره عملکرد بالای استادان خواهد بود
Detection of Quasi-periodic Oscillations in SGR 150228213
The detection of quasi-periodic oscillations (QPOs) in magnetar giant flares
(GFs) has brought a new perspective to study the mechanism of magnetar bursts.
Due to the scarcity of GFs, searching QPOs from magnetar short bursts is
reasonable. Here we report the detection of a high frequency QPO at
approximately 110 Hz and a wide QPO at approximately 60 Hz in a short magnetar
burst SGR 150228213, with a confidence level of 3.35. This burst was
initially attributed to 4U 0142+61 by /GBM on location, but we haven't
detected such QPOs in other bursts from this magnetar. We also found that there
was a repeating fast radio burst associated with SGR 150228213 on location.
Finally, we discuss the possible origins of SGR 150228213
Molecular characterization of new described kobuvirus in dogs with diarrhea in China
Canine kobuvirus (CaKVs) was a newly described virus detected in dogs in the US and Italy. To learn more about CaKVs, 5 of 106 fecal samples from diarrhea dogs were positive with CaKVs in China, and the full genome of CaKVs strain CH-1 isolated from dog with diarrhea was sequenced. The genome consists of 8186 nucleotides, excluding the 3′ poly (A) tail, and an open reading frame that maps between nucleotide positions 601 and 7943 which encodes a 2446 amino acid polyprotein. Based on the complete amino acid sequence of polyprotein, phylogenetic analysis showed that CH-1 was grouped along with other canine kobuvirus strains detected in the USA (US-PC0082, AN211D)
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