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Arch Virol ; 164(9): 2401-2410, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31243554


Rodent populations are known to be reservoirs of viruses with the potential to infect humans. However, a large number of such viruses remain undiscovered. In this study, we investigated the shedding of unknown viruses in long-tailed ground squirrel (Spermophilus undulatus) feces by high-throughput sequencing. A novel and highly divergent virus related to members of the genus Hepacivirus was identified in ground squirrel liver. This virus, tentatively named RHV-GS2015, was found to have a genome organization that is typical of hepaciviruses, including a long open reading frame encoding a polyprotein of 2763 aa. Sequence alignment of RHV-GS2015 with the most closely related hepaciviruses yielded p-distances of the NS3 and NS5B regions of 0.546 and 0.476, respectively, supporting the conclusion that RHV-GS2015 is a member of a new hepacivirus species, which we propose to be named "Hepacivirus P". Phylogenetic analysis of the NS3 and NS5B regions indicated that RHV-GS2015 shares common ancestry with other rodent hepaciviruses (species Hepacivirus E, and species Hepacivirus F), Norway rat hepacivirus 1 (species Hepacivirus G), and Norway rat hepacivirus 2 (species Hepacivirus H). A phylogenetic tree including the seven previously identified rodent hepaciviruses revealed extreme genetic heterogeneity among these viruses. RHV-GS2015 was detected in 7 out of 12 ground squirrel pools and was present in liver, lung, and spleen tissues. Furthermore, livers showed extremely high viral loads of RHV-GS2015, ranging from 2.5 × 106 to 2.0 × 108 copies/g. It is reasonable to assume that this novel virus is hepatotropic, like hepatitis C virus. The discovery of RHV-GS2015 extends our knowledge of the genetic diversity and host range of hepaciviruses, helping to elucidate their origins and evolution.

Hepacivirus/genética , Hepacivirus/isolamento & purificação , Sciuridae/virologia , Animais , China , Variação Genética , Genoma Viral , Hepacivirus/classificação , Hepacivirus/fisiologia , Especificidade de Hospedeiro , Fases de Leitura Aberta , Filogenia , Proteínas Virais/genética
Chin Med J (Engl) ; 131(18): 2216-2225, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30203797


Objective: A comprehensive review of the network regulation of exosomes and microRNAs (miRNAs) in neurodegenerative diseases was done, centering on the mechanism of the formation of exosomes and miRNAs and the sorting mechanism of exosomal miRNAs, with the aim to provide a theoretical basis in the search of biomarkers and the treatment of neurodegenerative diseases. Data Sources: The comprehensive search used online literature databases including NCBI PubMed, Web of Science, Google Scholar, and Baidu Scholar. Study Selection: The study selection was based on the following keywords: exosomes, miRNAs, central nervous system (CNS), and neurodegenerative diseases. The time limit for literature retrieval was from the year 2000 to 2018, with language restriction in English. Relevant articles were carefully reviewed, with no exclusions applied to study design and publication type. Results: Exosomes are the smallest nanoscale membranous microvesicles secreted by cells and contain important miRNAs, among other rich contents. In the CNS, exosomes can transport amyloid ß-protein, α-synuclein, Huntington-associated protein 1, and superoxide dismutase I to other cells. These events relieve the abnormal accumulation of proteins and aggravating neurological diseases. In some neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, miRNAs are pathologically altered as an inexorable course, suggesting that miRNAs may contribute neurodegeneration. Exosomes and miRNAs form a network to regulate the homeostasis of the CNS, both synergistically and individually. Conclusion: The network of exosomes and miRNAs that regulates CNS homeostasis is a promising biomarker for the diagnosis and treatment of neurodegenerative diseases.

PLoS One ; 13(3): e0193448, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29570703


OBJECTIVE: To investigate the usefulness of addition type liquid silicone rubber (ATLSR) as injectable implant after evisceration to maintain the eyeball volume in an animal experiment. METHODS: Twelve adult New Zealand white rabbits were included. One eye of each rabbit was randomly selected for evisceration with the fellow eye as control. ATLSR was injected to fill the eyeball socket after evisceration. In vivo observation and photographs were performed up to 24 weeks post-op. Two rabbits were sacrificed respectively at post-operative week 1, 2, 4, 8, 12 and 24. After enucleation, the vertical, horizontal and sagittal diameters of the experimental eyeballs were measured and compared with the control eyes. Histopathological studies were performed to evaluate signs of inflammation. RESULTS: Cornea remained clear throughout the observation period despite mild epithelial edema and neovascularization. Compared to the control eyes, the experimental eyes were significantly smaller in vertical diameter (17.00±1.17 vs. 17.54±1.11 mm, P<0.001), but larger in sagittal diameter (16.85±1.48 vs. 16.40±1.38 mm, P = 0.008), and had no significant difference in horizontal diameter (17.49±1.53 vs. 17.64±1.21 mm, P = 0.34). Postoperative inflammation was observed at one week after surgery, which peaked at 2-3 weeks, then regressed gradually. At week 12 and week 24, most of the inflammatory cells disappeared with some residual plasma cells and eosinophils. CONCLUSION: Injectable addition type silicon rubber may be a good choice for ocular implantation after evisceration, maintaining eyeball volume and cosmetically satisfactory when compared to the fellow eye. Spontaneous regression of inflammation implied good biocompatibility for at least 24 weeks.

Evisceração do Olho , Olho Artificial , Olho/efeitos dos fármacos , Olho/patologia , Elastômeros de Silicone/farmacologia , Animais , Injeções , Tamanho do Órgão/efeitos dos fármacos , Período Pós-Operatório , Coelhos , Elastômeros de Silicone/administração & dosagem
J Gen Virol ; 98(4): 612-623, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28100306


With advances in viral surveillance and next-generation sequencing, highly diverse novel astroviruses (AstVs) and different animal hosts had been discovered in recent years. However, the existence of AstVs in marmots had yet to be shown. Here, we identified two highly divergent strains of AstVs (tentatively named Qinghai Himalayanmarmot AstVs, HHMAstV1 and HHMAstV2), by viral metagenomic analysis in liver tissues isolated from wild Marmota himalayana in China. Overall, 12 of 99 (12.1 %) M. himalayana faecal samples were positive for the presence of genetically diverse AstVs, while only HHMAstV1 and HHMAstV2 were identified in 300 liver samples. The complete genomic sequences of HHMAstV1 and HHMAstV2 were 6681 and 6610 nt in length, respectively, with the typical genomic organization of AstVs. Analysis of the complete ORF 2 sequence showed that these novel AstVs are most closely related to the rabbit AstV, mamastrovirus 23 (with 31.0 and 48.0 % shared amino acid identity, respectively). Phylogenetic analysis of the amino acid sequences of ORF1a, ORF1b and ORF2 indicated that HHMAstV1 and HHMAstV2 form two distinct clusters among the mamastroviruses, and may share a common ancestor with the rabbit-specific mamastrovirus 23. These results suggest that HHMAstV1 and HHMAstV2 are two novel species of the genus Mamastrovirus in the Astroviridae. The remarkable diversity of these novel AstVs will contribute to a greater understanding of the evolution and ecology of AstVs, although additional studies will be needed to understand the clinical significance of these novel AstVs in marmots, as well as in humans.

Infecções por Astroviridae/veterinária , Astroviridae/classificação , Astroviridae/isolamento & purificação , Marmota/virologia , Animais , Astroviridae/genética , Infecções por Astroviridae/virologia , China , Análise por Conglomerados , Fezes/virologia , Ordem dos Genes , Genoma Viral , Fígado/virologia , Metagenômica , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Sintenia
Artigo em Chinês | MEDLINE | ID: mdl-19288923


OBJECTIVE: To establish a stable and efficient in vitro culture model for tachyzoites of Toxoplasma gondii RH strain. METHODS: Tachyzoites were inoculated into HeLa cells to establish an in vitro culture system. The proliferation of tachyzoites was observed under microscope by the method of Giemsa stain. At the same time, the longterm tachyzoites maintenance in HeLa cells was established, and the effect of different temperature and time on the yield and motility of tachyzoites were observed. RESULTS: The RH strain tachyzoites were cultured and maintained in HeLa cells. Most HeLa cells were destroyed 96 h after inoculation. In the long-term culture system, the proliferation of tachyzoites was stable and its virulence to mouse showed no decrease. Furthermore, tachyzoites in this system proliferated by 5-20 times and (1-5) x 10(7) tachyzoites were harvested. When cultured in HeLa cells at 37 degrees C for 72h then at 25 degrees C for another 120 h, the tachyzoites proliferated by more than 40 times with a motility rate of over 90%. However, rare HeLa cells left in the medium were found. CONCLUSION: Tachyzoites of T. gondii RH strain can be subcultured in HeLa cells for a long time, and high proliferation rate of tachyzoites can be obtained from this in vitro culture system.

Técnicas de Cultura de Células/métodos , Toxoplasma/isolamento & purificação , Animais , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos
Zhonghua Yu Fang Yi Xue Za Zhi ; 39(3): 199-202, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-15938856


OBJECTIVE: To discuss the possibility of hepatitis B virus (HBV) transmission through dental handpieces. METHODS: Investigation was carried on methods for disinfecting and sterilizing dental handpieces and the condition of HBsAg contamination on dental handpieces before and after disinfection and sterilization by randomly sampling all special stomatological hospitals and dental clinics in a same city and 10 dental departments from the third, second and first class hospitals. The possibility of HBV transmission through dental handpieces was probed by investigating whether ducks can be infected by bath liquid of dental handpieces contaminated by DHBV, while in such bath liquid, DHBV can not be detected by serum dot hybridization. RESULTS: From 2001 to 2004, in methods to disposing dental handpieces, the use of autoclave was remarkably increased while of the disinfectant wipe, immersion and other methods was remarkably decreased. The positive rate of HBsAg from dental handpieces in practice was 1.65%. It was evident that the bath liquid of dental handpieces contaminated by DHBV can conduct infection in vivo test of duck, while DHBV can not be detected in such bath liquid by serum dot hybridization, it is proved that the negative result of HBsAg in non-sterilized dental handpieces can not eliminate the possibility of HBV transmission through dental handpieces. CONCLUSION: There might exist the possibility of HBV transmission through dental handpieces however, the autoclaves might kill the virus contaminating on dental handpieces.

Instrumentos Odontológicos/virologia , Contaminação de Equipamentos , Hepatite B/transmissão , Esterilização/métodos , Animais , DNA Viral/sangue , Patos/virologia , Vírus da Hepatite B do Pato/genética , Vírus da Hepatite B do Pato/isolamento & purificação , Esterilização/normas