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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(3): 354-357, 2020 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-32294834

RESUMO

Objective: To explore influence on physical development of children aged 18 months from HIV-positive mothers for prevention mother to child transmission of HIV (PMTCT) in Guangxi Zhuang autonomous region, and provide evidence for the improvement PMTCT program. Methods: This retrospective case control study was conducted in 554 HIV negative infants aged 18 months whose HIV positive mothers had received PMTCT services reported through PMTCT system database from January 1, 2010 to December 31, 2017 and 1 109 healthy infants born in 2017, whose mothers were healthy, in Lingshan, Luzhai, and Hengxian counties, ranking top three counties with high HIV infection prevalence, in Guangxi. PMTCT data and physical development data such as height, weight and head circumference of children aged 18 months were collected. The physical dysplasia in the infants was defined as at least one of the three main indicators of height, weight and head circumference below the normal range. Results: The number of HIV-positive mother and their infants in the case group were 667 and 554 respectively, and the PMTCT rates were 91.15% (608/667) and 96.57% (535/554) respectively. HIV positive rate, mortality rate and mother to child transmission rate of the infants aged 18 months were 1.44% (8/554), 3.07% (17/554) and 1.91% (8/418) respectively, and the physical examination results of the infants aged 18 months showed that the physical dysplasia rate was 30.51% (169/554). Among the 1 109 infants in the control group, the physical dysplasia rate was 9.83% (109/1 109). The difference between the case group and the control group was significant (P<0.01). Conclusion: The PMTCT rates of HIV positive mother and their children were more than 90.00%, respectively. However, poor physical development rate of infants aged 18 months were more than 30.00%. The possible influence of PMTCT on physical development of the infants aged 18 months of HIV positive mother's needs to be further studied.


Assuntos
Desenvolvimento Infantil , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez , Estudos de Casos e Controles , China , Feminino , Humanos , Lactente , Gravidez , Estudos Retrospectivos
2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(3): 315-321, 2019 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-30884610

RESUMO

Objective: To understand the characteristics of HIV/AIDS epidemic in Guangxi Zhuang Autonomous Region (Guangxi) with a purpose to accurately provide scientific basis for prevention and control measures, 2010-2017. Methods: Data were retrieved from case reporting cards of Guangxi during 2010 to 2017 through National HIV/AIDS Comprehensive Response Information Management System. Data was analyzed using epidemiological methods such number of cases, proportion and rate. χ(2) test was used for statistical analysis. Results: The HIV positive rate was 12.53 per ten thousand (85 182/67 959 000) in Guangxi during 2010 to 2017. The number of newly diagnosed HIV/AIDS cases and the number of death yearly respectively increased by 22.34%(2 602/11 648) and 32.83% (952/2 900) in 2011 compared with 2010, and both showed a six-year continuous downward trend (the number of newly diagnosed cases respectively 12 229 cases, 10 877 cases, 9 460 cases, 9 190 cases, 8 848 cases, 8 680 cases, and the number of death respectively 3 888 cases, 3 316 cases, 2 914 cases, 2 717 cases, 2 595 cases, 2 600 cases) from 2012 to 2017. But proportion of late discovery remained above 50.00% (50.53%-57.06%) for eight-years continuously. The ratio of male and female was 2.47 ∶ 1 (60 639/24 543). The ratio of males and females aged 50 and over was 2.71∶1 (28 654/10 557). Proportion of the cases in 25-49 years old group and 50 years old group accounting for 47.40%(40 377/85 182) and 46.03% (39 211/85 182) respectively. The occupation was farmers accounting for 68.40% (58 262/85 182), housekeeping, housework and unemployment accounting for 11.21% (9 546/85 182), student accounting for 0.86% (729/85 182). Heterosexual transmission accounted for 90.60% (77 171/85 182, homosexual transmission accounted for 3.13% (2 669/85 182), injection drug use transmission accounted for 4.60%(3 924/85 182) and mother-to-child transmission accounted for 0.73% (619/85 182). Conclusions: The number of newly diagnosed cases and the number of death yearly showed a continuous downtrend for six-years from 2012 to 2017. However, proportion of late discovery remained above 50.00% for eight-years. The major route of infection was heterosexual transmission. With the change of HIV/AIDS newly epidemic mode in Guangxi, there are many new challenges for HIV/AIDS prevention and control work. Strategy of targeted intervention modes should be innovated for a new breakthrough.


Assuntos
Epidemias , Infecções por HIV/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(3): 326-330, 2017 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-28329933

RESUMO

Objective: To understand HIV-1 subtype characteristics and transmission clusters in elderly male clients and female sex workers (FSWs) of low-cost commercial sex venues in Guangxi Zhuang Autonomous Region, China. Methods: A cross sectional survey was conducted in FSWs and elderly male clients (≥50 years) of low-cost commercial sex venues in 4 cities and 9 counties in Guangxi Zhuang Autonomous Region by convenient sampling in 2012. The blood sample was collected from each case for HIV-1 antibody detection. The pol gene fragments were amplified and sequenced from viral RNA template extracted from plasma samples. The phylogenetic tree was constructed and the subtypes were identified. Results: A total of 4 048 elderly male clients and 784 FSWs were surveyed, and 116 HIV-1 infections were detected, the positive rate was 2.5% (103/4 048) in the clients and 1.7% (13/784) in FSWs. The gene amplification and sequencing of HIV-1 detected in 84 blood samples indicated that 53 pol gene sequences were successfully determined (48 blood samples from elderly male clients and 5 blood samples from FSWs). Among 53 pol sequences, 48(90.6% ), 4(7.5% ), and 1(1.9% ) sequences were identified as CRF01_AE, CRF08_BC, and CRF07_BC, respectively. Two transmission clusters were identified among CRF01_AE, including 4 sub-clusters. One transmission cluster was identified among CRF08_BC. The transmission cluster or sub-cluster were from the infected individuals at same low-cost commercial sex venue, or different low-cost commercial sex venues in the same town, or same place, or adjacent villages and towns. Conclusions: CRF01_AE was the predominant HIV-1 subtype among elderly male clients and FSWs of low-cost commercial sex venues in Guangxi Zhuang Autonomous Region, circulating in same venue or adjacent villages and towns. The HIV-1 positive male clients and FSWs might play an important role in the spread of the strains.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/genética , Profissionais do Sexo , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Fatores Etários , Idoso , Sequência de Bases , China/epidemiologia , Estudos Transversais , Feminino , Genes pol , Genótipo , Anticorpos Anti-HIV , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Masculino , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/sangue , Características de Residência , Trabalho Sexual
4.
Clin Radiol ; 72(4): 340.e1-340.e7, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28041652

RESUMO

AIM: To explore the altered spontaneous cerebral activity patterns and impaired functional regions in patients with diabetic retinopathy (DR) using resting-state functional magnetic resonance imaging (rs-fMRI) based on the amplitude of low-frequency fluctuations (ALFF) algorithm. MATERIALS AND METHODS: Twenty-one patients with DR (mean age, 54.9±9.9 years; 11 females) and 17 healthy control subjects (54.8±5.7 years; 9 females) were prospectively studied. The DR patients underwent laboratory tests. All individuals underwent a neuropsychological test. The differences in the ALFF values between the two groups were compared. The relationships between ALFF values and clinical measurements were analysed using a multiple-factor analysis. RESULTS: Compared to the controls, the DR group showed significantly increased ALFF values in the bilateral occipital gyrus, right lingual gyrus, and precuneus, and decreased values in the right posterior/anterior cerebellar lobe and the parahippocampal, fusiform, superior temporal, inferior parietal, and angular gyrus. Furthermore, the Montreal Cognitive Assessment (MoCA) scores were negatively correlated with decreased ALFF values in the right occipital lobe of the DR group, while increased ALFF values in the right precuneus and lingual gyrus were found to be positively correlated with glycosylated haemoglobin (HbA1c) levels. CONCLUSIONS: Patients with DR showed spontaneous cerebral activity abnormalities in many cerebral regions that were associated with cognitive impairments. HbA1c levels altered spontaneous cerebral activity in DR patients.


Assuntos
Encéfalo/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Retinopatia Diabética/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Descanso
5.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 34(10): 762-764, 2016 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-28043249

RESUMO

Objective: To investigate the changes in psychological state after occupational exposure in the AIDS occupational exposure population and related influencing factors, and to provide baseline data and a basis for related departments to conduct mental health prevention and intervention for personnel with occupational AIDS exposure. Methods: AIDS risk assessment was performed for all personnel with occupational AIDS exposure in 2014 in Nanning, China, and the Symptom Checklist-90 (SCL-90) psychological scale was used for psychological state evaluation at 24 hours, 1 week, and 3 months after occupational exposure in all persons who met the research criteria. Results: Most of the persons with occupational AIDS exposure came from secondary and tertiary hospitals (85%) , and nurses accounted for the highest percentage (78.3% ). The age ranged from 21 to 50 years, and the mean age was 31.02 ± 7.92 years. The persons with occupational AIDS exposure aged 20~29 years accounted for the highest percentage (51.6%) , and most persons (76.7%) graduated from junior colleges. Compared with the adult norm, there was significant increases in the total psychological score and the number of positive items after occupational exposure (P<0.05). The scores of all items at 24 hours were significantly higher than those at the other time points, and the scores of all items gradually decreased over time (F=227.24, 267.57, and 287.46, P<0.05). Compared with the adult norm, there were significant increases in the factor points at 24 hours and significant reductions in the factor points at 3 months (P<0.05). Compared with those at 24 hours, the factor scores at 3 months decreased significantly (P<0.05). Conclusion: Occupational AIDS exposure affects the mental status of related personnel, and the mental status at 24 hours after exposure is poor. Related departments should provide corresponding psychological counseling for the occupational exposure population at different exposure times.


Assuntos
Exposição Ocupacional , Síndrome da Imunodeficiência Adquirida , Adulto , China , Humanos , Ocupações , Medição de Risco , Estresse Psicológico , Inquéritos e Questionários , Adulto Jovem
6.
Appl Microbiol Biotechnol ; 86(1): 103-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19898843

RESUMO

Compared with steady state, oscillation in continuous very-high-gravity ethanol fermentation with Saccharomyces cerevisiae improved process productivity, which was thus introduced for the fermentation system composed of a tank fermentor followed by four-stage packed tubular bioreactors. When the very-high-gravity medium containing 280 g l(-1) glucose was fed at the dilution rate of 0.04 h(-1), the average ethanol of 15.8% (v/v) and residual glucose of 1.5 g l(-1) were achieved under the oscillatory state, with an average ethanol productivity of 2.14 g h(-1) l(-1). By contrast, only 14.8% (v/v) ethanol was achieved under the steady state at the same dilution rate, and the residual glucose was as high as 17.1 g l(-1), with an ethanol productivity of 2.00 g h(-1) l(-1), indicating a 7% improvement under the oscillatory state. When the fermentation system was operated under the steady state at the dilution rate of 0.027 h(-1) to extend the average fermentation time to 88 h from 59 h, the ethanol concentration increased slightly to 15.4% (v/v) and residual glucose decreased to 7.3 g l(-1), correspondingly, but the ethanol productivity was decreased drastically to 1.43 g h(-1) l(-1), indicating a 48% improvement under the oscillatory state at the dilution rate of 0.04 h(-1).


Assuntos
Etanol/metabolismo , Fermentação/fisiologia , Hipergravidade , Microbiologia Industrial/métodos , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Biocombustíveis , Reatores Biológicos , Meios de Cultura , Saccharomyces cerevisiae/crescimento & desenvolvimento
7.
Appl Microbiol Biotechnol ; 84(6): 1079-86, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19475405

RESUMO

An innovative consecutive batch fermentation process was developed for very high gravity (VHG) ethanol fermentation with the self-flocculating yeast under high biomass concentration conditions. On the one hand, the high biomass concentration significantly shortened the time required to complete the VHG fermentation and the duration of yeast cells suffering from strong ethanol inhibition, preventing them from losing viability and making them suitable for being repeatedly used in the process. On the other hand, the separation of yeast cells from the fermentation broth by sedimentation instead of centrifugation, making the process economically more competitive. The VHG medium composed of 255 g L(-1) glucose and 6.75 g L(-1) each of yeast extract and peptone was fed into the fermentation system for nine consecutive batch fermentations, which were completed within 8-14 h with an average ethanol concentration of 15% (v/v) and ethanol yield of 0.464, 90.8% of its theoretical value of 0.511. The average ethanol productivity that was calculated with the inclusion of the downstream time for the yeast flocs to settle from the fermentation broth and the supernatant to be removed from the fermentation system was 8.2 g L(-1) h(-1), much higher than those previously reported for VHG ethanol fermentation and regular ethanol fermentation with ethanol concentration around 12% (v/v) as well.


Assuntos
Etanol/metabolismo , Fermentação , Leveduras/metabolismo , Biomassa , Floculação , Microbiologia Industrial/economia , Microbiologia Industrial/métodos , Leveduras/química , Leveduras/crescimento & desenvolvimento
8.
Biotechnol Adv ; 27(6): 1118-1123, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19463939

RESUMO

Process oscillation characterized by long oscillation period and large oscillation amplitude was observed in continuous ethanol fermentation with Saccharomyces cerevisiae under very high gravity conditions. Metabolic flux analysis was applied to the fermentation system, and the results indicated that carbon flux distributions at the metabolic notes oscillated, correspondingly, and the root reason for the process oscillation was the intracellular metabolism of yeast cells. Cell cycle analysis with the flow cytometry showed that no cell-cycle-dependent synchronization of the daughter and mother cells occurred within the duration of the oscillation, and thus different mechanism existed compared with the oscillation observed in the continuous culture of Saccharomyces cerevisiae and triggered by the synchronization of the daughter and mother cells under specific conditions. Furthermore, the overall metabolic activity of the yeast cells was examined, which was found not exactly out of phase but lag behind ethanol concentration that accumulated within the fermentation system and its inhibition on the yeast cells as well, which supported the mechanistic speculation for the process oscillation: the lag response of yeast cells to ethanol inhibition.


Assuntos
Ciclo Celular , Etanol/metabolismo , Saccharomyces cerevisiae/metabolismo , Fermentação , Saccharomyces cerevisiae/citologia
9.
J Biotechnol ; 139(1): 55-60, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18938202

RESUMO

The effects of zinc supplementation were investigated in the continuous ethanol fermentation using self-flocculating yeast. Zinc sulfate was added at the concentrations of 0.01, 0.05 and 0.1 g l(-1), respectively. Reduced average floc sizes were observed in all the zinc-supplemented cultures. Both the ethanol tolerance and thermal tolerance were significantly improved by zinc supplements, which correlated well with the increased ergosterol and trehalose contents in the yeast flocs. The highest ethanol concentration by 0.05 g l(-1) zinc sulfate supplementation attained 114.5 g l(-1), in contrast to 104.1 g l(-1) in the control culture. Glycerol production was decreased by zinc supplementations, with the lowest level 3.21 g l(-1), about 58% of the control. Zinc content in yeast cells was about 1.4 microMol g(-1) dry cell weight, about sixfold higher than that of control in all the zinc-supplemented cultures, and close correlation of zinc content in yeast cells with the cell viability against ethanol and heat shock treatment was observed. These studies suggest that exogenous zinc addition led to a reprogramming of cellular metabolic network, resulting in enhanced ethanol tolerance and ethanol production.


Assuntos
Etanol/metabolismo , Fermentação , Leveduras/metabolismo , Sulfato de Zinco/metabolismo , Biomassa , Reatores Biológicos , Sobrevivência Celular , Ergosterol/metabolismo , Floculação , Glicerol/metabolismo , Temperatura , Trealose/metabolismo
10.
Biotechnol Bioeng ; 102(1): 113-21, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18949752

RESUMO

A bioreactor system composed of a stirred tank and three tubular bioreactors in series was established, and continuous ethanol fermentation was carried out using a general Saccharomyces cerevisiae strain and a very high gravity medium containing 280 g L(-1) glucose, supplemented with 5 g L(-1) yeast extract and 3 g L(-1) peptone. Sustainable oscillations of glucose, ethanol, and biomass were observed when the tank was operated at the dilution rate of 0.027 h(-1), which significantly affected ethanol fermentation performance of the system. After the tubular bioreactors were packed with 1/2'' Intalox ceramic saddles, the oscillations were attenuated and quasi-steady states were achieved. Residence time distributions were studied for the packed bioreactors by the step input response technique using xylose as a tracer, which was added into the medium at a concentration of 20 g L(-1), indicating that the backmixing alleviation assumed for the packed tubular bioreactors could not be established, and its contribution to the oscillation attenuation could not be verified. Furthermore, the role of the packing's yeast cell immobilization in the oscillation attenuation was investigated by packing the tubular bioreactors with packings with significant difference in yeast cell immobilization effects, and the experimental results revealed that only the Intalox ceramic saddles and wood chips with moderate yeast cell immobilization effects could attenuate the oscillations, and correspondingly, improved the ethanol fermentation performance of the system, while the porous polyurethane particles with good yeast cell immobilization effect could not. And the viability analysis for the immobilized yeast cells illustrated that the extremely lower yeast cell viability within the tubular bioreactors packed with the porous polyurethane particles could be the reason for their inefficiency, while the yeast cells loosely immobilized onto the surfaces of the Intalox ceramic saddles and wood chips could be renewed during the fermentation, guaranteeing their viability and making them more efficient in attenuating the oscillations. The packing Raschig rings without yeast cell immobilization effect did not affect the oscillatory behavior of the tubular bioreactors, further supporting the role of the yeast cell immobilization in the oscillation attenuation.


Assuntos
Reatores Biológicos , Meios de Cultura/química , Etanol/metabolismo , Fermentação , Saccharomyces cerevisiae/metabolismo , Biomassa , Células Imobilizadas , Glucose/metabolismo , Viabilidade Microbiana , Peptonas/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento
11.
J Appl Microbiol ; 105(6): 2076-83, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19120653

RESUMO

AIMS: To study fuel ethanol fermentation with Kluyveromyces marxianus ATCC8554 from Jerusalem artichoke (Helianthus tuberosus) grown in salina and irrigated with a mixture of seawater and freshwater. METHODS AND RESULTS: The growth and ethanol fermentation of K. marxianus ATCC8554 were studied using inulin as substrate. The activity of inulinase, which attributes to the hydrolysis of inulin, the main carbohydrate in Jerusalem artichoke, was monitored. The optimum temperatures were 38 degrees C for growth and inulinase production, and 35 degrees C for ethanol fermentation. Aeration was not necessary for ethanol fermentation with the K. marxianus from inulin. Then, the fresh Jerusalem artichoke tubers grown in salina and irrigated with 25% and 50% seawater were further examined for ethanol fermentation with the K. marxianus, and a higher ethanol yield was achieved for the Jerusalem artichoke tuber irrigated with 25% seawater. Furthermore, the dry meal of the Jerusalem artichoke tubers irrigated with 25% seawater was examined for ethanol fermentation at three solid concentrations of 200, 225 and 250 g l(-1), and the highest ethanol yield of 0.467, or 91.5% of the theoretical value of 0.511, was achieved for the slurry with a solid concentration of 200 g l(-1). CONCLUSIONS: Halophilic Jerusalem artichoke can be used for fuel ethanol production. SIGNIFICANCE AND IMPACT OF THE STUDY: Halophilic Jerusalem artichoke, not competing with grain crops for arable land, is a sustainable feedstock for fuel ethanol production.


Assuntos
Etanol/metabolismo , Glicosídeo Hidrolases/metabolismo , Helianthus/microbiologia , Kluyveromyces/enzimologia , Tubérculos/microbiologia , Reatores Biológicos/microbiologia , Água Doce , Inulina/metabolismo , Kluyveromyces/crescimento & desenvolvimento , Água do Mar , Temperatura
12.
J Biotechnol ; 124(2): 363-72, 2006 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-16494960

RESUMO

The intrinsic kinetics of continuous yeast cell growth and ethanol production for a self-flocculating fusant yeast strain SPSC01 was investigated by means of mechanically dispersing the flocs and correspondingly established floc size distribution on-line monitoring technique using the focused beam reflectance measurement system, through which the floc intra-particle mass transfer limitation was effectively eliminated, but its ethanol formation metabolism was not affected. Modified kinetic models were developed, which can be used to predict the continuous kinetic behaviors of SPSC01, especially when low dilution rates are applied and limiting substrate concentrations are undetectable and almost all kinetic models developed previously are failed in predicting corresponding kinetic behaviors. Both substrate and product inhibitions reported for freely suspended yeast cell ethanol production were also observed for SPSC01 when high gravity media were fed and relatively high levels of residual sugar and ethanol presented. Model parameters were evaluated through numerical calculation method and validated by experimental data mu = 0.584C(s)/0.155 + C(s) + C(2)(s)/160.7(1 -P/125)(3.68) + 0.004 for growth, nu = 1.998C(s)/0.427 + C(s) + C(2)(s)/366.7(1- P/125)(1.72) + 0.060 for ethanol production These intrinsic kinetic models can be further used to develop the observed kinetic models that quantitatively correlate the impact of the self-flocculating yeast cell size distributions on their apparent rates for yeast cell growth, substrate uptake and ethanol production and optimize the ethanol production process.


Assuntos
Algoritmos , Etanol/metabolismo , Fermentação , Microbiologia Industrial/métodos , Saccharomyces/crescimento & desenvolvimento , Saccharomyces/metabolismo , Reatores Biológicos , Floculação
13.
Biotechnol Bioeng ; 90(5): 523-31, 2005 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-15816023

RESUMO

Both intrinsic and observed kinetic investigations for those ethanol fermentations using self-flocculated yeast strains have been hindered by the lack of real online monitoring techniques and proper characterization methods for the flocs. An optical detecting technique, the focused beam reflectance measurement probe developed by Lasentec (Redmond, WA) was inserted into a fermentor to monitor the floc chord length distributions. Using a simulating system composed of the floc-buffer suspensions, the total floc chord length counts per second were directly correlated with the floc biomass concentrations so that the floc biomass concentrations can be in situ detected. Furthermore, a characterization method of the flocs was established by properly weighted treatments of the detected floc chord length distributions. When a real yeast floc ethanol fermentation system was detected during its intrinsic kinetic investigations in which the floc size needed to be controlled at a level of micrometer scale to eliminate inner mass transfer limitations, it was found and validated that CO(2) produced during fermentation exerted significant disturbances. By applying 1/length-weighted treatment, these disturbances were effectively overcome.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células/métodos , Contagem de Colônia Microbiana/métodos , Etanol/metabolismo , Nefelometria e Turbidimetria/métodos , Saccharomyces/citologia , Saccharomyces/fisiologia , Técnicas de Cultura de Células/instrumentação , Proliferação de Células , Contagem de Colônia Microbiana/instrumentação , Nefelometria e Turbidimetria/instrumentação
14.
Scand J Infect Dis ; 31(1): 21-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10381213

RESUMO

To elucidate the prevalence and clinical implications of infection with the newly described TT virus (TTV) among intravenous drug users (IVDUs) in Yunnan, southwest China, serum samples from 158 IVDUs (129 M, 29 F; mean age 26.1 +/- 5.5 years) were examined for TTV DNA by semi-nested polymerase chain reaction (PCR) using primers derived from the open reading frame (ORFI) of TTV DNA. The seroprevalence of viral markers of HIV, HBV, HCV and GB virus C/hepatitis G virus (GBV-C) infection was also examined. A molecular evolutionary analysis was performed. Thirty one (20%) of the IVDUs were positive for TTV DNA, and 34 (22%), 6 (4%), 98 (62%), 76 (48%), 136 (86%) and 65 (41%) were positive for anti-HIV, HBsAg, anti-HBs, anti-HBc, anti-HCV and GBV-C RNA, respectively. When all the subjects were classified according to TTV DNA positivity, no significant differences were observed in demographic, biochemical or virological characteristics between the 2 groups. TTV infection was in all cases associated with co-infection with 1 or more of the other aforementioned viruses. There were no significant differences in the various combinations of co-infection between TTV positive and negative groups. Phylogenetic analysis revealed that the TTV isolates obtained in the study could be grouped mainly into TTV genotype 1, and that some of the isolates belonged to subgroups other than those previously described. These results indicate that: 1) TTV infection is prevalent among IVDUs in China; 2) TTV probably has minor liver pathogenicity; and 3) new subgroups of genotype 1 and 2 exist in China.


Assuntos
Infecções por Vírus de DNA/virologia , Vírus de DNA/isolamento & purificação , Abuso de Substâncias por Via Intravenosa/virologia , Adulto , Anticorpos Antivirais/sangue , China/epidemiologia , Infecções por Vírus de DNA/epidemiologia , Infecções por Vírus de DNA/imunologia , Vírus de DNA/classificação , Vírus de DNA/genética , DNA Viral/sangue , Feminino , Flaviviridae/imunologia , Genótipo , HIV/imunologia , Hepacivirus/imunologia , Vírus da Hepatite B/imunologia , Humanos , Masculino , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Filogenia , Reação em Cadeia da Polimerase , Prevalência
15.
Cell Res ; 8(1): 63-71, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9570018

RESUMO

The effects of human EGFR to the malignant phenotype of human breast cancer cell line MDA-MB-231 were investigated experimentally. A retroviral vector containing a 5'1350bp fragment of the human EGFR cDNA in the antisense orientation was transfected into targeted cells by lipofectamine. The effects on cell proliferation, cell cycle and adherent ability to extracellular matrix (ECM) components were studied after the expression of antisense transcripts to EGFR 5'1350bp fragment in target cells. In vitro studies showed that the growth ability of the transfected cells was partially inhibited in comparison to parental cells and to cells transfected with the plasmid containing the neomycin resistance gene only. It was found that EGF (10 ng/ml) had an argumenation effect on the growth of transfected MDA-AS10 cells but not MDA-MB-231 cells. Flow cytometric analysis showed that the cell cycle of the transfected cells was abnormal with a decrease of cells in G2/M and S phases and an increase of cells in G1 phase, indicating a blockage in phase G1. Immunofluorescence of EGFR expression in transfectants stained with an anti-EGFR antibody was decreased and their growth in soft agarose was also severely impaired. The transfected cells showed less adherence to laminin (LN) and fibronectin (FN). In short, EGFR antisense RNA decreases the expression of EGFR on MDA-MB-231 cells and partially reverses their malignant phenotype as well.


Assuntos
Neoplasias da Mama/patologia , Adesão Celular/fisiologia , Receptores ErbB/fisiologia , RNA Antissenso , Neoplasias da Mama/genética , Ciclo Celular , Divisão Celular , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/análise , Receptores ErbB/genética , Fibronectinas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Laminina , Fenótipo , Transfecção , Células Tumorais Cultivadas
16.
J Infect Dis ; 175(1): 168-71, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8985213

RESUMO

The prevalence of GB virus C/hepatitis G virus (GBV-C/HGV) infection among intravenous drug users (IVDUs), patients with liver diseases, and blood donors in Nanning, southern China was studied. GBV-C/HGV RNA was detected by reverse transcription polymerase chain reaction with primers derived from the 5'-untranslated region. GBV-C/HGV RNA was detected in 64 of 85 IVDUs, 20 of 80 persons with liver disease, and 1 of 50 blood donors. Among IVDUs, GBV-C/HGV infection was associated with antibodies to hepatis C virus (HCV) and with hepatitis B surface antigen (HBsAg). Eleven nucleotide sequences were determined and analyzed by molecular evolutionary analysis. In a phylogenetic tree, the isolates were grouped in three clusters with GBV-C and HGV grouped in two clusters. These data indicate that GBV-C/HGV infection is common in China among IVDUs but uncommon among persons with liver disease without HBsAg or anti-HCV and that there is a new group of GBV-C/HGV.


Assuntos
Flaviviridae , Hepatite Viral Humana/epidemiologia , Doadores de Sangue , China/epidemiologia , Primers do DNA , Evolução Molecular , Flaviviridae/genética , Flaviviridae/isolamento & purificação , Hepatite B/complicações , Antígenos de Superfície da Hepatite B/sangue , Hepatite C/complicações , Anticorpos Anti-Hepatite C/sangue , Humanos , Hepatopatias/complicações , Filogenia , Reação em Cadeia da Polimerase , Prevalência , RNA Viral/análise , RNA Viral/genética , Abuso de Substâncias por Via Intravenosa/complicações
17.
J Hepatol ; 24(5): 622-4, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8773919

RESUMO

Tokita et al. reported the identification of hepatitis C virus type 7, 8 and 9 in Southeast Asia, based on the unweighed pair-group method with the arithmetic mean, a method that may not be appropriate when the nucleotide substitution rate is not constant over time. To determine more accurately the relationship of these proposed types 7, 8, and 9 with other types, a more appropriate approach, the neighbor-joining method, was applied to re-evaluate the phylogenetic relationship. A total of 660 HCV sequences, including the reported sequences, were collected from DNA databases. For every region, the nucleotide substitution rate was estimated by the 6-parameter method, and phylogenetic trees were constructed using the neighbor-joining method. The results of this analysis indicate that the newly proposed HCV types 7, 8 and 9 should be classified as type 6 subtypes. HCV type 6 appears to be diversified.


Assuntos
Hepacivirus/classificação , Nucleotídeos/química , Filogenia , Evolução Química
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