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61.
Le MT Wertheim HF Nguyen HD Taylor W Hoang PV Vuong CD Nguyen HL Nguyen HH Nguyen TQ Nguyen TV Van TD Ngoc BT Bui TN Nguyen BG Nguyen LT Luong ST Phan PH Pham HV Nguyen T Fox A Nguyen CV Do HQ Crusat M Farrar J Nguyen HT de Jong MD Horby P 《PloS one》2008,3(10):e3339
Background
Prior to 2007, highly pathogenic avian influenza (HPAI) H5N1 viruses isolated from poultry and humans in Vietnam were consistently reported to be clade 1 viruses, susceptible to oseltamivir but resistant to amantadine. Here we describe the re-emergence of human HPAI H5N1 virus infections in Vietnam in 2007 and the characteristics of the isolated viruses.Methods and Findings
Respiratory specimens from patients suspected to be infected with avian influenza in 2007 were screened by influenza and H5 subtype specific polymerase chain reaction. Isolated H5N1 strains were further characterized by genome sequencing and drug susceptibility testing. Eleven poultry outbreak isolates from 2007 were included in the sequence analysis. Eight patients, all of them from northern Vietnam, were diagnosed with H5N1 in 2007 and five of them died. Phylogenetic analysis of H5N1 viruses isolated from humans and poultry in 2007 showed that clade 2.3.4 H5N1 viruses replaced clade 1 viruses in northern Vietnam. Four human H5N1 strains had eight-fold reduced in-vitro susceptibility to oseltamivir as compared to clade 1 viruses. In two poultry isolates the I117V mutation was found in the neuraminidase gene, which is associated with reduced susceptibility to oseltamivir. No mutations in the M2 gene conferring amantadine resistance were found.Conclusion
In 2007, H5N1 clade 2.3.4 viruses replaced clade 1 viruses in northern Vietnam and were susceptible to amantadine but showed reduced susceptibility to oseltamivir. Combination antiviral therapy with oseltamivir and amantadine for human cases in Vietnam is recommended. 相似文献62.
Diego A. Duarte Alexandros Papadimitriou Richard E. Gilbert Kerri Thai Yanling Zhang Mariana A. B. Rosales José B. Lopes de Faria Jacqueline M. Lopes de Faria 《PloS one》2016,11(2)
Bone marrow-derived cells were demonstrated to improve organ function, but the lack of cell retention within injured organs suggests that the protective effects are due to factors released by the cells. Herein, we tested cell therapy using early outgrowth cells (EOCs) or their conditioned media (CM) to protect the retina of diabetic animal models (type 1 and type 2) and assessed the mechanisms by in vitro study. Control and diabetic (db/db) mice (8 weeks of age) were randomized to receive a unique intravenous injection of 5×105EOCs or 0.25 ml thrice weekly tail-vein injections of 10x concentrated CM and Wystar Kyoto rats rendered diabetic were randomized to receive 0.50 ml thrice weekly tail-vein injections of 10x concentrated CM. Four weeks later, the animals were euthanized and the eyes were enucleated. Rat retinal Müller cells (rMCs) were exposed for 24 h to high glucose (HG), combined or not with EOC-conditioned medium (EOC-CM) from db/m EOC cultures. Diabetic animals showed increase in diabetic retinopathy (DR) and oxidative damage markers; the treatment with EOCs or CM infusions significantly reduced this damage and re-established the retinal function. In rMCs exposed to diabetic milieu conditions (HG), the presence of EOC-CM reduced reactive oxygen species production by modulating the NADPH-oxidase 4 system, thus upregulating SIRT1 activity and deacetylating Lys-310-p65-NFκB, decreasing GFAP and VEGF expressions. The antioxidant capacity of EOC-CM led to the prevention of carbonylation and nitrosylation posttranslational modifications on the SIRT1 molecule, preserving its activity. The pivotal role of SIRT1 on the mode of action of EOCs or their CM was also demonstrated on diabetic retina. These findings suggest that EOCs are effective as a form of systemic delivery for preventing the early molecular markers of DR and its conditioned medium is equally protective revealing a novel possibility for cell-free therapy for the treatment of DR. 相似文献
63.
64.
Guan-Sheng Jiao Seongjin Kim Mahtab Moayeri April Thai Lynne Cregar-Hernandez Linda McKasson Sean OMalley Stephen H. Leppla Alan T. Johnson 《Bioorganic & medicinal chemistry letters》2018,28(2):134-139
Anthrax is a highly lethal disease caused by the Gram-(+) bacteria Bacillus anthracis. Edema toxin (ET) is a major contributor to the pathogenesis of disease in humans exposed to B. anthracis. ET is a bipartite toxin composed of two proteins secreted by the vegetative bacteria, edema factor (EF) and protective antigen (PA). Our work towards identifying a small molecule inhibitor of anthrax edema factor is the subject of this letter. First we demonstrate that the small molecule probe 5′-Fluorosulfonylbenzoyl 5′-adenosine (FSBA) reacts irreversibly with EF and blocks enzymatic activity. We then show that the adenosine portion of FSBA can be replaced to provide more drug-like molecules which are up to 1000-fold more potent against EF relative to FSBA, display low cross reactivity when tested against a panel of kinases, and are nanomolar inhibitors of EF in a cell-based assay of cAMP production. 相似文献
65.
Organic–inorganic perovskites have demonstrated an impressive potential for the design of the next generation of solar cells. Perovskite solar cells (PSCs) are currently considered for scaling up and commercialization. Many of the lab‐scale preparation methods are however difficult to scale up or are environmentally unfriendly. The highest efficient PSCs are currently prepared using the antisolvent method, which utilizes a significant amount of an organic solvent to induce perovskite crystallization in a thin film. An antisolvent‐free method is developed in this work using flash infrared annealing (FIRA) to prepare methylammonium lead iodide (MAPbI3) PSCs with a record stabilized power conversion efficiency of 18.3%. With an irradiation time of fewer than 2 s, FIRA enables the coating of glass and plastic substrates with pinhole‐free perovskite films that exhibit micrometer‐size crystalline domains. This work discusses the FIRA‐induced crystallization mechanism and unveils the main parameters controlling the film morphology. The replacement of the antisolvent method and the larger crystalline domains resulting from flash annealing make FIRA a highly promising method for the scale‐up of PSC manufacture. 相似文献
66.
Quynh-Nhi Thi Le Khanh-Lam Phung Van-Thuy Thi Nguyen Katherine L. Anders Minh-Nguyet Nguyen Diem-Tuyet Thi Hoang Thuy-Tien Thi Bui Vinh-Chau Van Nguyen Guy E. Thwaites Cameron Simmons Stephen Baker 《International breastfeeding journal》2018,13(1):46
Background
There is a paucity of data regarding risk factors associated with suboptimal breastfeeding practices in urbanized areas of low-middle income countries (LMICs).Methods
Through a large prospective birth cohort, which enrolled 6706 infants in Vietnam between 2009 and 2013, we investigated the practice of exclusive breastfeeding during hospital stay in urban and semi-rural populations and aimed to identify factors associated with suboptimal breastfeeding practices. Univariate and multivariable logistic regression were performed to determine factors associated with not exclusive breastfeeding during hospital stay.Results
Of 6076 mothers, 33% (2187) breastfed their infant exclusively before hospital discharge; 9% (364/4248) in urban and 74% (1823/2458) in semi-rural areas. Exclusive breastfeeding up to 4 months was recorded in 15% (959/6210) of participants; this declined to <?1% (56/6093) at 6 months. Delivery by Caesarean section (Odds Ratio [OR] 0.07; 95% Confidence Interval [CI] 0.04, 0.11 and OR 0.05; 95% CI 0.03, 0.08) and neonatal complications (OR 0.2; 95% CI 0.07, 0.47 and OR 0.25; 95% CI 0.14, 0.46) were common and highly significant risk factors associated with a lack of exclusive breastfeeding during hospital stay in urban and semi-rural settings, respectively.Conclusions
To our knowledge, this is the first large-scale investigation aimed at identifying factors associated with exclusive breastfeeding during hospital stay in Vietnam. Breastfeeding promotion strategies should prioritize common risk factors in hospital, such as Caesarean section and neonatal complications, and other location specific factors associated with socioeconomics.67.
Ankit X. Sharma Ezekiel B. Quittner-Strom Young Lee Joshua A. Johnson Sarah A. Martin Xinxin Yu Jianping Li John Lu Zheqing Cai Shiuhwei Chen May-yun Wang Yiyi Zhang Mackenzie J. Pearson Andie C. Dorn Jeffrey G. McDonald Ruth Gordillo Hai Yan Dung Thai William L. Holland 《Cell reports》2018,22(7):1760-1773
68.
Karin G. Michels-Rautenstrauss Christian Y. Mardin Wido M. Budde Thomas Liehr J. Polansky Thai Nguyen Vincent Timmerman C. Van Broeckhoven Gottfried O. H. Naumann Rudolf A. Pfeiffer B. W. Rautenstrauss 《Human genetics》1998,102(1):103-106
Autosomal dominant juvenile open angle glaucoma (JOAG) is an early-onset form of primary open angle glaucoma (POAG), which
has been linked to chromosome 1q21–q31. Recently, mutations in the trabecular meshwork inducible glucocorticoid response gene
(TIGR), one of the candidate genes mapped in this region, were identified in glaucoma patients of several families. We screened
for mutations of the TIGR gene in two German families with JOAG and in 100 unselected sporadic cases of POAG. In the first
family we identified a Pro370Leu mutation and in the second family a Gly367Arg mutation cosegregating with the glaucoma phenotype.
No pathogenic mutation was found in 100 sporadic cases but a Tyr347Tyr polymorphism was found in two patients. Furthermore,
fluorescence in situ hybridization (FISH) analysis was used to map a TIGR-specific yeast artificial chromosome to 1q24.3–q25.2.
Received: 19 June 1997 / Accepted: 12 August 1997 相似文献
69.
Differential Genomic Effects of Six Different TiO2 Nanomaterials on Human Liver HepG2 Cells 下载免费PDF全文
Sheau‐Fung Thai Kathleen A. Wallace Carlton P. Jones Hongzu Ren Eric Grulke Benjamin T. Castellon James Crooks Kirk T. Kitchin 《Journal of biochemical and molecular toxicology》2016,30(7):331-341
Human HepG2 cells were exposed to six TiO2 nanomaterials (with dry primary particle sizes ranging from 22 to 214 nm, either 0.3, 3, or 30 μg/mL) for 3 days. Some of these canonical pathways changed by nano‐TiO2 in vitro treatments have been already reported in the literature, such as NRF2‐mediated stress response, fatty acid metabolism, cell cycle and apoptosis, immune response, cholesterol biosynthesis, and glycolysis. But this genomic study also revealed some novel effects such as protein synthesis, protein ubiquitination, hepatic fibrosis, and cancer‐related signaling pathways. More importantly, this genomic analysis of nano‐TiO2 treated HepG2 cells linked some of the in vitro canonical pathways to in vivo adverse outcomes: NRF2‐mediated response pathways to oxidative stress, acute phase response to inflammation, cholesterol biosynthesis to steroid hormones alteration, fatty acid metabolism changes to lipid homeostasis alteration, G2/M cell checkpoint regulation to apoptosis, and hepatic fibrosis/stellate cell activation to liver fibrosis. 相似文献
70.
Guillaume Gaullier Simona Miron Sabrina Pisano Rémi Buisson Yann-Va? Le?Bihan Carine Tellier-Lebègue Wala Messaoud Pierre Roblin Beatriz G. Guimar?es Robert Thai Marie-Josèphe Giraud-Panis Eric Gilson Marie-Hélène Le?Du 《Nucleic acids research》2016,44(4):1962-1976
Telomere integrity is essential to maintain genome stability, and telomeric dysfunctions are associated with cancer and aging pathologies. In human, the shelterin complex binds TTAGGG DNA repeats and provides capping to chromosome ends. Within shelterin, RAP1 is recruited through its interaction with TRF2, and TRF2 is required for telomere protection through a network of nucleic acid and protein interactions. RAP1 is one of the most conserved shelterin proteins although one unresolved question is how its interaction may influence TRF2 properties and regulate its capacity to bind multiple proteins. Through a combination of biochemical, biophysical and structural approaches, we unveiled a unique mode of assembly between RAP1 and TRF2. The complete interaction scheme between the full-length proteins involves a complex biphasic interaction of RAP1 that directly affects the binding properties of the assembly. These results reveal how a non-DNA binding protein can influence the properties of a DNA-binding partner by mutual conformational adjustments. 相似文献