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1.
Int J Mol Sci ; 24(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37569563

RESUMO

Group A rotaviruses (RVAs) are major etiologic agents of gastroenteritis in infants and young children worldwide. To study the prevalence and genetic characteristics of RVAs, a hospital-based surveillance study was conducted in Wuhan, China from June 2019 through May 2022. The detection rates of RVAs were 19.40% (142/732) and 3.51% (8/228) in children and adults, respectively. G9P[8] was the predominant genotype, followed by G8P[8] and G3P[8]. G8P[8] emerged and was dominant in the 2021-2022 epidemic season. The genome constellation of six G8P[8] strains was assigned to G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Phylogenetic analysis revealed that the VP7, VP4, VP2, VP3, NSP1, NSP2, NSP3, and NSP5 genes of these G8P[8] strains clustered closely with those of the G8P[8] strains in Asia and were distant from those of the P[8] and G2P[4] strains simultaneously detected in Wuhan. In contrast, the VP1, VP6, and NSP4 genes were closely related to the typical G2P[4] rotavirus, including those of G2P[4] strains simultaneously detected in Wuhan. The detection rate of RVAs decreased in the COVID-19 pandemic era. It was deduced that the G8P[8] rotaviruses that emerged in China may be reassortants, carrying the VP6, VP1, and NSP4 genes derived from the G2P[4] rotavirus in the backbone of the neighboring DS-1-like G8P[8] strains represented by CAU17L-103.


Assuntos
COVID-19 , Infecções por Rotavirus , Rotavirus , Lactente , Criança , Humanos , Pré-Escolar , Rotavirus/genética , Infecções por Rotavirus/genética , Filogenia , Pandemias , Genoma Viral , COVID-19/genética , Genótipo , China/epidemiologia
2.
Natl Sci Rev ; 10(6): nwad081, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37404853

RESUMO

Thermally activated ultrafast diffusion, collision and combination of metal atoms comprise the fundamental processes of synthesizing burgeoning subnanometer metal clusters for diverse applications. However, so far, no method has allowed the kinetically controllable synthesis of subnanometer metal clusters without compromising metal loading. Herein, we have developed, for the first time, a graphene-confined ultrafast radiant heating (GCURH) method for the synthesis of high-loading metal cluster catalysts in microseconds, where the impermeable and flexible graphene acts as a diffusion-constrained nanoreactor for high-temperature reactions. Originating from graphene-mediated ultrafast and efficient laser-to-thermal conversion, the GCURH method is capable of providing a record-high heating and cooling rate of ∼109°C/s and a peak temperature above 2000°C, and the diffusion of thermally activated atoms is spatially limited within the confinement of the graphene nanoreactor. As a result, due to the kinetics-dominant and diffusion-constrained condition provided by GCURH, subnanometer Co cluster catalysts with high metal loading up to 27.1 wt% have been synthesized by pyrolyzing a Co-based metal-organic framework (MOF) in microseconds, representing one of the highest size-loading combinations and the quickest rate for MOF pyrolysis in the reported literature. The obtained Co cluster catalyst not only exhibits an extraordinary activity similar to that of most modern multicomponent noble metal counterparts in the electrocatalytic oxygen evolution reaction, but is also highly convenient for catalyst recycling and refining due to its single metal component. Such a novel GCURH technique paves the way for the kinetically regulated, limited diffusion distance of thermally activated atoms, which in turn provides enormous opportunities for the development of sophisticated and environmentally sustainable metal cluster catalysts.

3.
Inorg Chem ; 62(22): 8615-8625, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37218057

RESUMO

Uranium-based catalysts have been regarded as promising candidates for N2 fixation owing to the low-valent uranium metal active sites possessing the ability to enhance the electron back-donating to the π* antibonding orbitals of N2 for N≡N dissociation. Herein, we report a directional half-wave rectified alternating current electrochemical method to confine oxygen-rich uranium precursors over ultrathin 2D GO nanosheets. The as-prepared uranium catalysts exhibit a considerable Faradaic efficiency of 12.7% for NH3 and the NH3 yield rate of 18.7 µg h-1 mg-1 for N2 electroreduction. Operando XAS and isotope-labeling FTIR further unravel the preferred nitrogen adsorption reaction intermediate N-(2Oax-1 U-4Oeq) and confirm the key *N2Hy intermediate species derived from the fed N2 gas. Theoretical simulations demonstrate that the U-O atomic interface originated from U 5f-O 2p orbital hybridization can accumulate partial charge from GO, which can facilitate the N≡N dissociation and lower the thermodynamic energy barrier of the first hydrogenation step.

4.
Nano Lett ; 23(9): 3826-3834, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37115709

RESUMO

Modifying the atomic and electronic structure of platinum-based alloy to enhance its activity and anti-CO poisoning ability is a vital issue in hydrogen oxidation reaction (HOR). However, the role of foreign modifier metal and the underlying ligand effect is not fully understood. Here, we propose that the ligand effect of single-atom Cu can dynamically modulate the d-band center of Pt-based alloy for boosting HOR performance. By in situ X-ray absorption spectroscopy, our research has identified that the potential-driven structural rearrangement into high-coordination Cu-Pt/Pd intensifies the ligand effect in Pt-Cu-Pd, leading to enhanced HOR performance. Thereby, modulating the d-band structure leads to near-optimal hydrogen/hydroxyl binding energies and reduced CO adsorption energies for promoting the HOR kinetics and the CO-tolerant capability. Accordingly, PtPdCu1/C exhibits excellent CO tolerance even at 1,000 ppm impurity.

5.
Nat Commun ; 14(1): 1720, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36977693

RESUMO

The rational steering and construction of efficient and stable atomic interfaces is highly desirable but rather challenging in solar energy conversion. Here, we report an in-situ oxygen impregnation strategy to build abundant atomic interfaces composed of homogeneous Ru and RuOx amorphous hybrid-mixture with ultrafast charge transfer, for solar hydrogen evolution with sacrificial agent free. Via in-situ synchrotron X-ray absorption and photoelectron spectroscopies, we can precisely track and identify the gradual formation of atomic interfaces towards homogeneous Ru-RuOx hybrid-structure at the atomic level. Benefiting from the abundant interfaces, the amorphous RuOx sites can intrinsically trap the photoexcited hole within an ultrafast process (<100 fs), and the amorphous Ru sites enable subsequent electron transfer (~1.73 ps). Hence, this hybrid-structure triggers long-lived charge-separated states, and results in a high hydrogen evolution rate of 60.8 µmol·h-1. This design integrating the two sites fulfilled each half-reaction in a single hybrid-structure suggests potential guidelines towards efficient artificial photosynthesis.

6.
Angew Chem Int Ed Engl ; 62(16): e202218630, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36732313

RESUMO

The transformation from metal nanocluster catalysts to metal single-atom catalysts is an important procedure in the rational design of atomically dispersed metal catalysts (ADCs). However, the conversion methods often involve high annealing temperature as well as reducing atmosphere. Herein, we reported a continuous and convenient approach to transfer Pd nanocluster into Pd single-atom in a ligand assisted annealing procedure, by which means we reduced its activating temperature low to 400 °C. Using ex-situ microscopy and spectroscopy, we comprehensively monitored the structural evolution of Pd species though the whole atomization process. Theoretical calculation revealed that the structural instability caused by remaining Cl ligands was the main reason for this low-temperature transformation. The present atomization strategy and mechanistic knowledge for the conversion from cluster to atomic dispersion provides guidelines for the rational design of ADCs.

7.
Sci Bull (Beijing) ; 67(19): 2001-2012, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36546210

RESUMO

Actinide-based catalysts have been regarded as promising candidates for N2 fixation owing to their unique 5f orbital with flexible oxidation states. Herein, we report for the first time the dispersion of uranium (U) single atoms on TiO2 nanosheets via oxygen vacancy confinement for N2 electroreduction. The single-atom U catalyst exhibited a high NH3 yield of 40.57 µg h-1 mg-1, with a reasonably high Faraday efficiency of 25.77%, ranking first among the reported nitrogen-free catalysts. Isotope-labeling operando synchrotron infrared spectroscopy verifies that the key *N2Hy intermediate species was derived from the N2 gas of the feed. By using operando X-ray absorption spectroscopy, we found enhanced metal-support interaction between U single atoms and TiO2 lattice with more U-Olatt coordination under working conditions. Theoretical simulations suggest that the evolved 1Oads-U-4Olatt moieties act as a critical electron-feedback center, lowering the thermodynamic energy barrier for the N2 dissociation and the first hydrogenation step. This work provides the possibility of tailoring the interaction between metal active sites and supports for designing high-performance actinide-based single-atom catalysts.

8.
Nanomicro Lett ; 13(1): 189, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34490543

RESUMO

Surface chemistry modification represents a promising strategy to tailor the adsorption and activation of reaction intermediates for enhancing activity. Herein, we designed a surface oxygen-injection strategy to tune the electronic structure of SnS2 nanosheets, which showed effectively enhanced electrocatalytic activity and selectivity of CO2 reduction to formate and syngas (CO and H2). The oxygen-injection SnS2 nanosheets exhibit a remarkable Faradaic efficiency of 91.6% for carbonaceous products with a current density of 24.1 mA cm-2 at -0.9 V vs RHE, including 83.2% for formate production and 16.5% for syngas with the CO/H2 ratio of 1:1. By operando X-ray absorption spectroscopy, we unravel the in situ surface oxygen doping into the matrix during reaction, thereby optimizing the Sn local electronic states. Operando synchrotron radiation infrared spectroscopy along with theoretical calculations further reveals that the surface oxygen doping facilitated the CO2 activation and enhanced the affinity for HCOO* species. This result demonstrates the potential strategy of surface oxygen injection for the rational design of advanced catalysts for CO2 electroreduction.

9.
J Phys Chem Lett ; 12(33): 8016-8023, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34433277

RESUMO

Exploring high-efficiency catalysts for the electrochemical hydrogen evolution reaction (HER) in alkaline environments is attractive but remains challenging. Here we report a coordination regulation strategy to tune the atomic structure of Ru cluster catalysts supported on Ti3C2Tx MXene (Ru-Ti3C2Tx) for the HER. We identify that the coordination number (CN) of Ru-Ru could be slightly regulated from 2.1 to 2.8 by adjusting the synthesized temperature so as to achieve an optimal catalytic configuration. The Ru-Ti3C2Tx with a CNRu-Ru of 2.8 exhibits the best catalytic activity with a low overpotential of 96 mV at 10 mA cm-2 and a mass activity about 11.5 times greater than the commercial Pt/C catalyst. Density functional theory calculations demonstrated that the small Ru clusters have a stronger covalent interaction with Ti3C2Tx support leading to an optimal ΔGH* value. This work opens up a general avenue to modulate the coordination environment of catalysts for the HER.

10.
J Am Chem Soc ; 143(30): 11317-11324, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34293258

RESUMO

The development of atomically precise dinuclear heterogeneous catalysts is promising to achieve efficient catalytic performance and is also helpful to the atomic-level understanding on the synergy mechanism under reaction conditions. Here, we report a Ni2(dppm)2Cl3 dinuclear-cluster-derived strategy to a uniform atomically precise Ni2 site, consisting of two Ni1-N4 moieties shared with two nitrogen atoms, anchored on a N-doped carbon. By using operando synchrotron X-ray absorption spectroscopy, we identify the dynamically catalytic dinuclear Ni2 structure under electrochemical CO2 reduction reaction, revealing an oxygen-bridge adsorption on the Ni2-N6 site to form an O-Ni2-N6 structure with enhanced Ni-Ni interaction. Theoretical simulations demonstrate that the key O-Ni2-N6 structure can significantly lower the energy barrier for CO2 activation. As a result, the dinuclear Ni2 catalyst exhibits >94% Faradaic efficiency for efficient carbon monoxide production. This work provides bottom-up target synthesis approaches and evidences the identity of dinuclear sites active toward catalytic reactions.

11.
J Colloid Interface Sci ; 585: 452-458, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33268061

RESUMO

Ruthenium nanoparticles (Ru NPs) with face-centered cubic (fcc) structure possess higher catalytic activity than that with hexagonal close-packed (hcp) structure. However, a high temperature above 1800 K is needed for the formation of the metastable fcc Ru phase. In this study, we present a tunable fabrication strategy of fcc and hcp Ru NPs by laser ablation of Ru target in solvents. In methanol, ethanol or acetone organic solvent, both fcc and hcp Ru NPs encapsulated in carbon layer could be obtained, while in deionized water only pure hcp Ru NPs formed. The extreme conditions, that is, the laser-target interaction induced high temperature and high-pressure plasma plume (4000-5000 K, 10-15 GPa) together with its subsequent quenching process, favored the formation of metastable fcc phase. Significantly, the graphite carbon layers sourced from the thermal decomposition of solvent molecules prevent the further evolution of metastable fcc phase into stable hcp phase. Clarification of the solvents and pulse energy effects promise the tunable fabrication of Ru NPs with desired crystallographic structure during laser ablation in liquids (LAL).

12.
Pathogens ; 9(10)2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023203

RESUMO

Rotaviruses are a major etiologic agent of gastroenteritis in infants and young children worldwide. To learn the shift of genotypes and genetic characteristics of Rotavirus A (RVA) causing diarrhea in children and adults, a hospital-based surveillance of rotavirus was conducted in Wuhan, China from June 2011 through May 2019, and representative virus strains were phylogenetically analyzed. Among a total of 6733 stool specimens collected from both children and adults with acute gastroenteritis, RVA was detected in 25.5% (1125/4409) and 12.3% (285/2324) of specimens, respectively. G9P[8] was the most common genotype (74.5%), followed by G1P[8] (8.7%), G2P[4] (8.4%), and G3P[8] (7.3%), with G9P[8] increasing rapidly during the study period. The predominant genotype shifted from G1P[8] to G9P[8] in 2012-2013 epidemic season. G12P[6] strain RVA/Human-wt/CHN/Z2761/2019/G12P[6] was detected in April 2019 and assigned to G12-P[6]-I1-R1-C1-M1-A1-N1-T2-E1-H1 genotypes. Phylogenetic analysis revealed that VP7, VP4, VP6, VP3, NSP1, NSP2, and NSP5 genes of Z2761 clustered closely with those of Korean G12P[6] strain CAU_214, showing high nucleotide identities (98.0-98.8%). The NSP3 gene of Z2761 was closely related to those of G2P[4] and G12P[6] rotaviruses in Asia. All the eleven gene segments of Z2761 kept distance from those of cocirculating G9P[8], G1P[8], and G3P[8] strains detected in Wuhan during this study period. This is the first identification of G12 rotavirus in China. It is deduced that Z2761 is a reassortant having DS-1-like NSP3 gene in the background of G12P[6] rotavirus genetically close to CAU_214.

13.
Food Environ Virol ; 11(2): 126-137, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30739247

RESUMO

A gastroenteritis outbreak occurred in a university in May, 2017, Wuhan, China. The epidemiological survey and pathogen analysis were conducted to identify the pathogen and control this outbreak. Feces or anal swabs from individuals, water, and swabs taken from tap surfaces of the secondary water supply system (SWSS) and foods were collected for the detection of viruses and pathogenic enteric bacteria by real-time RT-PCR and culture, respectively. Nucleotide sequences were determined by RT-PCR and direct sequencing. Genotyping, phylogenetic, and recombination analyses were conducted by a web-based genotyping tool, MEGA, and RDP4 programs, respectively. Of 144 individuals enrolled, 75 met the case definitions. The epidemic curve showed one peak of incidence suggesting the most probable spread of a single common source. In total, 33 specimens were collected before disinfection of the SWSS. Of these, norovirus was detected and identified as GII.P17-GII.17 with 100% nucleotide sequence identity among the strains detected in ten students (10/14), a maintenance worker (1/2) dealing with the SWSS, four water samples (4/8), and two swabs taken from tap surfaces (2/3). Pathogens including Vibrio cholerae, Salmonella, Shigella, Vibrio parahaemolyticus, Bacillus cereus, enteropathogenic Escherichia coli, rotavirus, astrovirus, and sapovirus were negative. The GII.17 strains in this outbreak clustered closely in the same branch of the phylogenetic tree, and slightly apart from the strains of other cities in China, neighboring countries and regions, European and American countries. This gastroenteritis outbreak was deduced to be attributed to GII.P17-GII.17 norovirus contamination of the SWSS.


Assuntos
Infecções por Caliciviridae/virologia , Água Doce/virologia , Gastroenterite/virologia , Norovirus/isolamento & purificação , Adolescente , Adulto , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Surtos de Doenças , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Norovirus/classificação , Norovirus/genética , Filogenia , Poluição da Água , Abastecimento de Água , Adulto Jovem
14.
Int J Clin Exp Med ; 8(3): 4697-702, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26064406

RESUMO

Cranial Mesenchymal chondrosarcoma (MC) and those that occurred in brain parenchymal were fairly rare aggressive neoplasm commonly affecting the bone of young adults. Here, we reported a case with intracranial MC, invading Broca's area, a rare site not previously reported, which was presumed to be a glioma. We performed a gross total resection guided by intra-operative magnetic resonance imaging (iMRI) combined with neuronavigation. Follow-up shows no language and other brain function loss. Furthermore, we present a review of literature. We emphasized the importance of gross total resection guiding by the combination of iMRI and neuronavigation, which was proved to be both reliable and effective in language preservation.

15.
Zhonghua Wai Ke Za Zhi ; 53(5): 362-7, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26082252

RESUMO

OBJECTIVE: To propose a clinically practical and simple fiber tracking method for language pathways, and to explore its feasibility in preoperative planning for brain tumors adjacent to the language cortex. METHODS: Diffusion tensor imaging was examined in 18 healthy subjects and 13 patients with brain tumors adjacent to the language cortex between December 2013 and June 2014. The associated fibers of language pathways were reconstructed using a commercial software (Syngo workstation). Firstly, the feasibility of fiber tracking method for language pathways in healthy subjects were studied, and then its application was assessed in patients with brain tumors. The anatomic relationship between tumors and the associated fibers was analyzed. RESULTS: By selecting appropriate regions of interest, the associated fibers in the dorsal pathways (superior longitudinal fasciculus/arcuate fasciculus, including both direct and indirect pathways) and ventral pathways (uncinate fasciculus, middle longitudinal fasciculus, inferior longitudinal fasciculus and inferiorfronto-occipital fasciculus) were reconstructed in all 18 healthy subjects. In patients with brain tumors, the relationship between the tumors and adjacent associated fibers were divided into two types: adjacent associated fibers could be displaced or separated, and involved the superior longitudinal fasciculus/arcuate fasciculus (n=6), middle longitudinal fasciculus (n=4), uncinate fasciculus (n=3), inferior longitudinal fasciculus (n=3) and inferiorfronto-occipital fasciculus (n=2); alternatively, the adjacent associated fibers were infiltrated or destroyed, and involved the inferiorfronto-occipital fasciculus (n=10), uncinate fasciculus (n=8), middle longitudinal fasciculus (n=5), inferior longitudinal fasciculus (n=4) and superior longitudinal fasciculus/arcuate fasciculus (n=3). CONCLUSIONS: The associated fibers of language pathways could be visualized rapidly and in real-time by fiber tracking technology based on diffusion tensor imaging. This is feasible for preoperative planning regarding brain tumors adjacent to the language cortex.


Assuntos
Neoplasias Encefálicas/cirurgia , Córtex Cerebral/cirurgia , Idioma , Vias Neurais , Imagem de Tensor de Difusão , Humanos , Complicações Pós-Operatórias/prevenção & controle
16.
Infect Genet Evol ; 33: 55-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25891280

RESUMO

We report here the whole genomic analyses of two G4P[6] (RVA/Human-wt/CHN/E931/2008/G4P[6], RVA/Human-wt/CHN/R1954/2013/G4P[6]), one G3P[6] (RVA/Human-wt/CHN/R946/2006/G3P[6]) and one G4P[8] (RVA/Human-wt/CHN/E2484/2011/G4P[8]) group A rotavirus (RVA) strains detected in sporadic cases of diarrhea in humans in the city of Wuhan, China. All the four strains displayed a Wa-like genotype constellation. Strains E931 and R1954 shared a G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1 constellation, whilst the 11 gene segments of strains R946 and E2484 were assigned to G3-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1 and G4-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 genotypes, respectively. Phylogenetically, the VP7 gene of R946, NSP3 gene of E931, and 10 of 11 gene segments of E2484 (except for VP7 gene) belonged to lineages of human RVAs. On the other hand, based on available data, it was difficult to ascertain porcine or human origin of VP3 genes of strains E931 and R946, and NSP2 genes of strains R946 and R1954. The remaining genes of E2484, E931, R946 and R1954 were close to those of porcine RVAs from China, and/or porcine-like human RVAs. Taken together, our observations suggested that strain R1954 might have been derived from porcine RVAs, whilst strains R946 and E931 might be reassortants possessing human RVA-like gene segments on a porcine RVA genetic backbone. Strain E2484 might be derived from reassortment events involving acquisition of a porcine-like VP7 gene by a Wa-like human RVA strain. The present study provided important insights into zoonotic transmission and complex reassortment events involving human and porcine RVAs, reiterating the significance of whole-genomic analysis of RVA strains.


Assuntos
Genômica , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/microbiologia , Rotavirus/genética , Proteínas Virais/genética , Alelos , Substituição de Aminoácidos , Animais , Genoma Viral , Genótipo , Humanos , Mutação , Filogenia , Vírus Reordenados , Rotavirus/classificação , Infecções por Rotavirus/transmissão
17.
PLoS One ; 9(3): e88850, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24676363

RESUMO

BACKGROUND: Rotaviruses are a major etiologic agent of gastroenteritis in infants and young children worldwide. Since the latter of the 1990s, G3 human rotaviruses referred to as "new variant G3" have emerged and spread in China, being a dominant genotype until 2010, although their genomic evolution has not yet been well investigated. METHODS: The complete genomes of 33 G3P[8] human rotavirus strains detected in Wuhan, China, from 2000 through 2013 were analyzed. Phylogenetic trees of concatenated sequences of all the RNA segments and individual genes were constructed together with published rotavirus sequences. RESULTS: Genotypes of 11 gene segments of all the 33 strains were assigned to G3-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, belonging to Wa genogroup. Phylogenetic analysis of the concatenated full genome sequences indicated that all the modern G3P[8] strains were assigned to Cluster 2 containing only one clade of G3P[8] strains in the US detected in the 1970s, which was distinct from Cluster 1 comprising most of old G3P[8] strains. While main lineages of all the 11 gene segments persisted during the study period, different lineages appeared occasionally in RNA segments encoding VP1, VP4, VP6, and NSP1-NSP5, exhibiting various allele constellations. In contrast, only a single lineage was detected for VP7, VP2, and VP3 genes. Remarkable lineage shift was observed for NSP1 gene; lineage A1-2 emerged in 2007 and became dominant in 2008-2009 epidemic season, while lineage A1-1 persisted throughout the study period. CONCLUSION: Chinese G3P[8] rotavirus strains have evolved since 2000 by intra-genogroup reassortment with co-circulating strains, accumulating more reassorted genes over the years. This is the first large-scale whole genome-based study to assess the long-term evolution of common human rotaviruses (G3P[8]) in an Asian country.


Assuntos
Evolução Molecular , Genoma Viral , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/genética , Substituição de Aminoácidos , China/epidemiologia , Frequência do Gene , Genes Virais , Variação Genética , Genótipo , História do Século XXI , Humanos , Fenótipo , Filogenia , Prevalência , RNA Viral , Rotavirus/classificação , Infecções por Rotavirus/história , Estações do Ano , Análise de Sequência de DNA , Análise Espaço-Temporal
18.
J Med Virol ; 85(10): 1712-23, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23868809

RESUMO

Little is known about the epidemiological characteristics of HIV/hepatitis C virus (HCV) co-infection in cities in China with low HIV prevalence. This study evaluated the level of exposure to different risk factors associated with HCV transmission and characterized the distribution of HCV genotypes in 356 HIV-1-positive patients in Wuhan, central China. HIV transmission routes were distributed as follows: heterosexual contact, male-to-male sexual contact, intravenous drug use, blood transfusion, and unknown route. HCV antibodies were detected by a third-generation enzyme-linked immunosorbent assay. HCV-positive plasmas were subjected to RNA extraction, RT-PCR amplification, and sequencing. Phylogenetic analysis characterized HCV subtypes and the evolutionary origin of circulating HCV strains. Ninety-two of 356 (25.8%) patients infected with HIV were anti-HCV-positive. Among co-infected patients, the predominant risk for HCV transmission was intravenous drug use (87.3%). Six HCV subtypes (1a, 1b, 2a, 3a, 3b, and 6a) were detected. HCV genotype 6a was most prevalent, occurring in 39.3% of all patients, followed by genotypes 1b (24.7%), 3b (18.0%), and 3a (9.8%). The least frequent genotypes were 1a (4.9%) and 2a (3.3%). Intravenous drug use was strongly associated with genotype 6a, and infection by blood or blood product transfusion was strongly associated with genotype 1b. Genotype 2a was detected only among those infected by male-to-male sexual contact. The distribution of HCV subtypes suggests that the city plays a crucial role as a hub of HCV transmission in China. Exposure to multiple risk factors associated with HCV transmission was common among patients co-infected with HIV and HCV.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/epidemiologia , Adulto , Idoso , China/epidemiologia , Análise por Conglomerados , Coinfecção/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Infecções por HIV/virologia , Hepacivirus/isolamento & purificação , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Prevalência , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Análise de Sequência de DNA , Comportamento Sexual , Abuso de Substâncias por Via Intravenosa/complicações , Adulto Jovem
19.
Dalton Trans ; 42(36): 13084-91, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23877151

RESUMO

In methanol-aqueous solutions, three novel structure-directing agents (SDAs) were generated in situ and presented. These in situ reactions feature N-methylation transformations between CH3OH solvent and organic cyclic aliphatic and aromatic amines, i.e. 2-methylpiperazine, 1,4-diazabicyclo[2,2,2]octane (dabco) and 3-(aminomethyl)pyridine. Distinct from conventional Eschweiler-Clarke methylation containing excess formic acid and formaldehyde, such a direct methylation transformation from methanol molecules is unique. In the presence of new SDAs, three organically templated zinc phosphites/phosphates, [pmpip][Zn3(HPO3)4] I (pmpip = N,N,N',N'-tetramethyl-2-methylpiperazinium), [dmdabco][Zn3(HPO3)4] II (dmdabco = N,N'-dimethyl-1,4-diazabicyclo[2,2,2]octane) and [Hmampy][Zn2(HPO4)3] III (mampy = N-methyl-3-(aminomethyl)pyridine), have been prepared and structurally characterized by elemental analysis, IR, thermogravimetric analysis, powder and single-crystal X-ray diffraction. Compound I exhibits a 2D layer with eight-membered apertures, compounds II and III possess a 3D interrupted framework with intersecting 8-, 10- and 12-ring channels (for II), and 8-, 10-ring channels (for III), respectively.

20.
Infect Genet Evol ; 16: 103-12, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23403096

RESUMO

The group A rotavirus (RVA) G3P[9] is a rare VP7-VP4 genotype combination, detected occasionally in humans and cats. Other than the prototype G3P[9] strain, RVA/Human- tc/JPN/AU-l/1982/G3P3[9], the whole genomes of only two human G3P[9] RVA strains and two feline G3P[9] RVA strains have been analyzed so far, revealing complex evolutionary patterns, distinct from that of AU-1. We report here the whole genomic analyses of two human G3P[9] RVA strains, RVA/Human-tc/CHN/L621/2006/G3P[9] and RVA/Human-wt/CHN/E2451/2011/G3P[9], detected in patients with diarrhea in China. Strains L621 and E2451 possessed a H6 NSP5 genotype on an AU-1-like genotype constellation, not reported previously. However, not all the genes of L621 and E2451 were closely related to those of AU-1, or to each other, revealing different evolutionary patterns among the AU-1-like RVAs. The VP7, VP4, VP6 and NSP4 genes of E2451 and L621 were found to cluster together with human G3P[9] RVA strains believed to be of possible feline/canine origin, and feline or raccoon dog RVA strains. The VP1, VP3, NSP2 and NSP5 genes of E2451 and L621 formed distinct clusters in genotypes typically found in feline/canine RVA strains or RVA strains from other host species which are believed to be of feline/canine RVA origin. The VP2 genes of E2451 and L621, and NSP3 gene of L621 clustered among RVA strains from different host species which are believed to have a complete or partial feline/canine RVA origin. The NSP1 genes of E2451 and L621, and NSP3 gene of E2451 clustered with AU-1 and several other strains possessing a complete or partial feline RVA strain BA222-05-like genotype constellation. Taken together, these observations suggest that nearly all the eleven gene segments of G3P[9] RVA strains L621 and E2451 might have originated from feline/canine RVAs, and that reassortments may have occurred among these feline/canine RVA strains, before being transmitted to humans.


Assuntos
Infecções por Rotavirus/virologia , Rotavirus/genética , Animais , Gatos , Pré-Escolar , Cães , Genoma Viral , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Rotavirus/classificação , Infecções por Rotavirus/genética , Proteínas não Estruturais Virais/genética
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