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1.
Gastrointest Endosc ; 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38593933

RESUMO

BACKGROUND AND AIMS: The aim of this study was to investigate the safety and efficacy of appendicoscopy using a single-operator cholangioscope (SOC) for the management of acute obstructive appendicitis. METHODS: This study describes 110 cases of acute obstructive appendicitis managed with the use of appendicoscopy between January 2021 and June 2023. The success rate (technical + clinical), procedure time, time to abdominal pain relief according to a visual analog scale score, postoperative length of hospital stay, and adverse event rates were recorded and analyzed. RESULTS: The technical success rate of appendicoscopy was 96.4%, and the clinical success rate was 91.8%. The mean ± standard deviation procedure time was 20.9 ± 10 minutes. The abdominal pain score at 6 hours after the procedure was ≤3 (visual analog scale method) in 99.1% of patients. The average length of postoperative hospital stay was 3.5 ± 1.5 days. No adverse events occurred. CONCLUSIONS: Appendicoscopy seems to be a feasible and effective alternative therapy for the accurate diagnosis and treatment of acute obstructive appendicitis.

2.
Molecules ; 28(7)2023 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-37049720

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of liver malignancy and remains a global health threat. The objective of the current study was to determine whether the combination of a cold-water extracted polysaccharide-protein complex from Grifolia frondosa (GFG) and cyclophosphamide (CTX) could inhibit tumor growth by suppressing the expression of angiogenesis-related proteins in H22 tumor-bearing mice. The results showed that the inhibition rate of GFG combined with CTX on H22 tumors was 65.29%, which was significantly higher than that of GFG treatment alone (24.82%). GFG combined with CTX significantly increased the expression levels of vascular endothelial growth factor, basic fibroblast growth factor, matrix metalloproteinase 2, and matrix metalloproteinase 9. Additionally, thymus index, spleen index, natural killer (NK) cell activity, interferon-γ (IFN-γ), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and interleukin-2 (IL-2) levels increased significantly after GFG treatment, especially after high-doses of GFG combined with CTX treatment (p < 0.05). The thymus index, spleen index, NK cell activity, IFN-γ, IL-1ß, TNF-α, and IL-2 levels were 1.90, 1.46, 1.30, 2.13, 1.64, 2.03, and 1.24 times of those treated with CTX alone. Thus, we proposed that GFG can alleviate the side effects of CTX by relieving the immunosuppressive effect, liver/renal injury, and oxidative stress. In conclusion, the combination of GFG and CTX for cancer treatment may be a promising strategy, and GFG is expected to be a potential adjuvant alternative for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Grifola , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Interleucina-2/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Grifola/metabolismo , Metaloproteinase 2 da Matriz , Fator de Necrose Tumoral alfa , Fator A de Crescimento do Endotélio Vascular , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Interferon gama , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Linhagem Celular Tumoral
3.
BMC Gastroenterol ; 21(1): 264, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34118868

RESUMO

BACKGROUND: The aim of this study is to investigate the difference of serum pepsinogen (PG) baseline levels in different regions of China and its influencing factors. METHODS: From October 2016 to October 2018, asymptomatic health checkup people who underwent nasal endoscopy in nine health management centers in different regions of China were collected. Lifestyle questionnaires were conducted, and serum PG and gastroscopy were performed. The differences in PG levels in baseline population (OLGA-0 grade) were studied according to geographical subregions of China. SPSS software was used for statistical analysis. RESULTS: 1922 patients were included in the final analysis. Compared with the non-atrophy (OLGA-0) group, PGR levels in atrophy group (OLGA-I to IV) were significantly decreased with the atrophy degree (p < 0.05). A total of 1590 baseline people (OLGA-0) were included in the study, including 254 from South China, 574 from East China, 210 from Southwest China, 332 from Northeast China, and 220 from Central/Northern China. There were significant differences in baseline PGI levels among the five regions (p < 0.05). The PGII levels were also different among the five regions, except for Central/Northern versus Southern China. PGR (PGI/PGII ratio) levels in Southern China were higher than other four regions. Further studies were conducted on the related factors that might affect the baseline PG level, which was affected by nationality, dietary habits, smoking, Helicobacter pylori infection and other related factors. CONCLUSION: Influenced by many factors, the baseline PG levels are different in different regions of China. In the follow-up studies of PG cut-off value, different PG cut-off value based on region may be more effective in the screening of gastric cancer and precancerous lesions in China.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , China/epidemiologia , Estudos Transversais , Infecções por Helicobacter/epidemiologia , Humanos , Pepsinogênio A , Pepsinogênio C
5.
Biology (Basel) ; 12(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36671814

RESUMO

Mushroom polysaccharides are a kind of biological macromolecule extracted from the fruiting body, mycelium or fermentation liquid of edible fungi. In recent years, the research on mushroom polysaccharides for alleviating metabolic diseases, inflammatory bowel diseases, cancers and other symptoms by changing the intestinal microenvironment has been increasing. Mushroom polysaccharides could promote human health by regulating gut microbiota, increasing the production of short-chain fatty acids, improving intestinal mucosal barrier, regulating lipid metabolism and activating specific signaling pathways. Notably, these biological activities are closely related to the molecular weight, monosaccharide composition and type of the glycosidic bond of mushroom polysaccharide. This review aims to summarize the latest studies: (1) Regulatory effects of mushroom polysaccharides on gut microbiota; (2) The effect of mushroom polysaccharide structure on gut microbiota; (3) Metabolism of mushroom polysaccharides by gut microbiota; and (4) Effects of mushroom polysaccharides on gut microbe-mediated diseases. It provides a theoretical basis for further exploring the mechanism of mushroom polysaccharides for regulating gut microbiota and gives a reference for developing and utilizing mushroom polysaccharides as promising prebiotics in the future.

6.
Int J Biol Macromol ; 239: 124291, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37028620

RESUMO

Grifola frondosa polysaccharide-protein complex (G. frondosa PPC) is a polymer which consists of polysaccharides and proteins/peptides linked by covalent bonds. In our previous ex vivo research, it has been demonstrated that a cold-water extracted G. frondosa PPC has stronger antitumor activity than a G. frondosa PPC extracted from boiling water. The main purpose of the current study was to further evaluate the anti-hepatocellular carcinoma and gut microbiota regulation effects of two PPCs isolated from G. frondosa at 4 °C (GFG-4) and 100 °C (GFG-100) in vivo. The results exhibited that GFG-4 remarkably upregulated the expression of related proteins in TLR4-NF-κB and apoptosis pathway, thereby inhibiting the development of H22 tumors. Additionally, GFG-4 increased the abundance of norank_f__Muribaculaceae and Bacillus and reduced the abundance of Lactobacillus. Short chain fatty acids (SCFAs) analysis suggested that GFG-4 promoted SCFAs production, particularly butyric acid. Conclusively, the present experiments revealed GFG-4 has the potential of anti-hepatocellular carcinoma growth via activating TLR4-NF-κB pathway and regulating gut microbiota. Therefore, G. frondosa PPCs could be considered as safe and effective natural ingredient for treatment of hepatocellular carcinoma. The present study also provides a theoretical foundation for the regulation of gut microbiota by G. frondosa PPCs.


Assuntos
Carcinoma , Microbioma Gastrointestinal , Grifola , Animais , Camundongos , NF-kappa B/metabolismo , Grifola/química , Receptor 4 Toll-Like , Polissacarídeos/farmacologia , Polissacarídeos/química , Água/química
7.
Int J Biol Macromol ; 218: 1021-1032, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35863663

RESUMO

Grifola frondosa (G. frondosa) is widely known for its anti-tumor potential, which has been demonstrated by numerous scientific researches. In this study, two water soluble polysaccharide-protein complexes were extracted from G. frondosa at 4 °C (GFG-4) and 100 °C (GFG-100) and purified. Compared with GFG-100, GFG-4 had a higher protein content and molecular weight. The main monosaccharides of GFG-4 and GFG-100 were rhamnose, glucose, and galactose, with an approximate ratio of 3.00: 1.00: 0.86 and 2.85: 1.00: 0.94, respectively. The Fourier transform infrared spectra indicated that the two polysaccharide-protein complexes displayed characteristic functional groups of polysaccharides and proteins, and mainly contain pyranose ring with α-glycosidic linkage. Atomic force microscope images showed that both GFG-4 and GFG-100 exhibited straight chains, and GFG-4 possessed a relatively abundant fraction of branched chains. Intriguingly, GFG-4 showed a stronger antiproliferative activity against HepG2 cells than GFG-100. The mechanisms were further investigated by quantitative real-time PCR and western blot, it found that GFG-4 inhibited the proliferation of HepG2 cells mainly through the intrinsic activation of mitochondrial pathway and the Fas/FasL-mediated Caspase-8/-3 pathway. Conclusively, G. frondosa cold-water extracted polysaccharide-protein complexes could be used as a functional food for preventing or treating hepatocellular carcinoma.


Assuntos
Grifola , Grifola/metabolismo , Células Hep G2 , Humanos , Mitocôndrias , Monossacarídeos/metabolismo , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Proteínas/metabolismo , Água/metabolismo
8.
Appl Psychol Health Well Being ; 13(3): 653-676, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32981153

RESUMO

BACKGROUND: Prior research observes associations between race-based stressors (e.g. stereotypes) and the compromised psychological and sociocultural adaptation of international students. METHODS: Using an explanatory sequential mixed-methods design (196 survey responses and 51 in-depth interviews), this study examined stereotypes perceived by Chinese students arriving on US college campuses after 2010, their interpretations of the new stereotypes, and the associated psychosocial adaptation challenges they had to navigate. RESULTS: Our findings suggested multiple dimensions of the stereotypes this recent wave of Chinese students perceived from their American peers, including stereotypes pertinent to their financial background (frequency effect sizes = 37.6% and 51% for quantitative and qualitative results, respectively), academic abilities (20.1% and 13.7%), personality characteristics (16.5% and 19.6%), and social attitudes and behaviors (12.9% and 9.8%). Further, this study observed that the new, prevalent stereotypes (e.g. being wealthy) might foster intergroup tension and pit Chinese students against their American peers and that some Chinese students experienced psychological issues (e.g. lower levels of collective self-esteem and feelings of shame) due to the stereotypes of wealth-flaunting Chinese students. CONCLUSIONS: This study contributes uniquely to the literature by unpacking the new stereotypes using a mixed-methods design and points to important practical implications for university services.


Assuntos
Estudantes , Universidades , China , Humanos , Autoimagem , Inquéritos e Questionários , Estados Unidos
9.
Front Oncol ; 11: 652574, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504781

RESUMO

BACKGROUND: Pepsinogens (PGs) can be used for gastric cancer (GC) screening, but the cutoff levels vary among studies, and PG levels are influenced by numerous factors. The aim of this article is to examine the diagnostic value of PG levels and Helicobacter pylori (Hp) status for GC and atrophic gastritis screening in asymptomatic individuals undergoing health checkup in China. PATIENTS AND METHODS: This was a multicenter cross-sectional study of subjects who underwent health checkup from 10/2016 to 10/2018 at nine International Healthcare Centers in China. All participants underwent gastroscopy and pathological examination, serum PG, 13C-urea breath test, and/or Hp serological current infection marker rapid test, all on the same day. PG-related parameters were analyzed in different Hp subgroups and regions. RESULTS: The patients were grouped as non-atrophic (NAG, n = 1,590), mild to moderate atrophic (MAG, n = 273), severe atrophic (SAG, n = 49), and GC (n = 10). The serum PG levels in these groups decreased with increasing pathological severity. In the same pathological groups, PGI and PGII levels were higher in the Hp-positive subgroup, while PGR (PGI/PGII ratio) was lower (P < 0.05). The best cutoff values for atrophy diagnosis were PGI ≤73.1 ng/ml and PGR ≤9.8, for severe atrophy were PGI ≤63.9 ng/ml and PGR ≤9.09, and for GC was PGR ≤4.7 (all P < 0.05 and area under the curve >0.7). The cutoff points varied with Hp status and China regions. CONCLUSION: Serum PG levels might be used for the screening of gastric atrophic gastritis lesions. The results suggest that different cutoff values should possibly be used in different Hp status groups and geographical regions, but it will have to be validated in future studies. Future studies should also examine the value of PG levels for GC detection.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): m621, 2010 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-21579279

RESUMO

The title polymeric compound, [Zn(C(8)H(5)Cl(2)O(3))(2)](n), was prepared by reaction of zinc(II) chloride with 2,4-dichloro-phenoxy-acetic acid and sodium hydroxide under hydro-thermal conditions. The Zn(II) atom is coordinated in a distorted tetra-hedral environment by four O atoms from four 2,4-dichloro-phenoxy-acetate ligands. Each ligand bridges two Zn(II) atoms, forming a polymeric chain along the a axis. Adjacent chains are connected via C-H⋯Cl hydrogen bonds.

11.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): m199, 2010 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-21579663

RESUMO

The title compound, {[Cu(2)(C(8)H(5)Cl(2)O(3))(C(10)H(8)N(2))(2)]NO(3)}(n) was prepared by reacting copper(II) nitrate with 4,4'-bipyridine (4,4'-bipy) and (2,4-dichloro-phen-oxy)acetic acid under solvothermal conditions. Each of two copper(I) atoms in the asymmetric unit is three-coordinated by two N atoms from two 4,4'-bipy ligands and one O atom from the (2,4-dichloro-phen-oxy)acetate ligand. As both ligands act as bridging ligands, a double-stranded chain structure is observed.

12.
Dev Psychol ; 56(11): 2121-2136, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32915051

RESUMO

Asian American adolescents' cross-race friendships are poorly understood, partially due to the model minority stereotype. Using data from 915 Asian American adolescents from the National Longitudinal Study for Adolescent to Adult Health, the present study examined the influence of cross-race friendships (based on peer nomination data) on Asian American adolescents' psychological well-being trajectories, as well as the moderating role of school context (numeric marginalization, school prejudice). Results showed that cross-race friendships promoted Asian American adolescents' psychological well-being, particularly in early adolescence and in schools where adolescents lacked critical mass of same-race peers or where prejudice was widespread. Similar findings were observed for cross-race friendships with the majority group, and more evident effects emerged for cross-ethnic friendships. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Asiático , Amigos , Adolescente , Humanos , Relações Interpessoais , Estudos Longitudinais , Grupo Associado , Instituições Acadêmicas
13.
Int J Med Mushrooms ; 22(12): 1183-1190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33463935

RESUMO

A systematic study was carried out to compare the chemical composition and biological activities of wood-cultured and sack-cultured Ganoderma lucidum (WG and SG, respectively). The proximate composition, microelement content, and functional compounds of the two different cultivated mushrooms were investigated. Antioxidant and hypoglycemic activities of polysaccharide and phenolic extracts of WG and SG were also investigated. The phenolic extracts exhibited higher antioxidant and hypoglycemic activity than the polysaccharidic extracts, and activities of the WG extracts were better than those of the SG extracts. Therefore, wood culture is a superior method of artificial cultivation for the production of such antioxidant and hypoglycemic activities.


Assuntos
Meios de Cultura/química , Extratos Vegetais/química , Reishi/crescimento & desenvolvimento , Antioxidantes/química , Antioxidantes/metabolismo , Meios de Cultura/metabolismo , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Reishi/química , Reishi/metabolismo
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(5): 1118-21, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18720814

RESUMO

A novel calix[4]arene derivative(25,27-two2-methylquinoline t-butylcalix[4]arene, MQBC) with the lower rim modified fluorescence groups was synthesized. IR spectra, elemental analysis, HNMR spectra and MS were used to determine its structure. Meanwhile, the spectra characters of MQBC and the fluorescent behaviors of the complex with zinc(II) and copper (II) were investigated, and the results showed that the lower rim oxygen atoms in calix[4]arenes may act as electrons donor to metal ions. Calix[4] arene was chosen as a basic skeleton of a photoresponsive ion carrier because its quinolin derivatives are known to emit fluorescence and absorb UV in the solution, and the information of the complex with metal ions will be known by spectra experiment. The UV absorbance became weak at the band of 226 nm but was enhanced at the band of 315 nm when it bound zinc ions, The complex constant(K) and binding ratio(x) were determined to be 2 064 L x mol(-1) and 1, respectively, by UV spectra experiment. It is expected that MQBC will be applied to the detection of trace zinc ions. The fluorecence spectra experiment found that MQBC is has feeble fluorecence attributed to the intramolecular photoinduced electron transfer(PET) between oxygen atoms and methylquinoline groups. When MQBC was combined with zinc(II) and copper(II), it caused the inhibiting photoinduced electron transfer process between oxygen atoms and methylquinoline groups leading to the enhancement of fluorescence. In addition, the photoinduced electron mechanism was discussed and the influence of the concentration of zinc(II) and copper(II) on the fluorescence intensities was studied.

16.
Harm Reduct J ; 4: 6, 2007 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-17286871

RESUMO

OBJECTIVE: To estimate HIV prevalence among injecting drug users (IDUs) in a drug trafficking city in southwest Sichuan Province, China. METHODS: A total of 314 IDUs was invited to participate in the cross-sectional survey in 2004 through community outreach recruitment and peer referrals. Blood sample was taken for HIV antibody testing and a structured questionnaire was administered to collect information on socio-demographics, drug using and sexual behaviors. RESULTS: HIV prevalence among IDUs was 17.8% (56/314), about one half higher than that in previous survey in 2002 (11.3%, 43/379). Yi and other minority ethnicity (Odds ratio [OR], 3.1; 95% confidence interval [CI], 1.7-5.8; P < 0.001), and total times of sharing injecting equipment 1-9 times versus none, OR, 2.7; 95% CI 1.2-6.2; P = 0.02; and > or = 10 times versus none, OR, 7.5; 95% CI, 3.2-17.7; P < 0.001) were independent risk factors for HIV infection. CONCLUSION: IDUs with high prevalence rates of HIV and equipment sharing behavior in the drug trafficking city may serve a source for further spread of HIV to other areas in China. The increasing trend of HIV epidemic among IDUs underscores the urgency of scaling up interventions.

17.
World J Gastroenterol ; 10(11): 1589-93, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15162531

RESUMO

AIM: To investigate the prevalence and risk factors of HCV/HIV coinfection in injection drug abusers (IDAs) in Lianshan Yi Autonomous Prefecture of Sichuan province, China. METHODS: From November 8, 2002 to November 29, 2002, a community-based survey was conducted to investigate the demographic characteristics, patterns of shared injectors devices and sexual behaviors in IDAs. Blood samples were also collected to test HCV and HIV infection. A total of 379 subjects were recruited in the study through community outreach and peer recruiting methods. RESULTS: Of the 379 IDAs, the HCV prevalence and HIV prevalence were 71.0% and 11.3%, respectively, and HCV/HIV coinfection was 11.3%. HCV infection was found in 100% and 67.3% of HIV-positive and HIV-negative IDAs, respectively. HIV prevalence was 16.0% in HCV positive IDAs while none of the HCV negative IDAs was positive for HIV. Ethnicity, shared needles or syringes and cotton in the past 3 mo and syphilis infection were associated with HCV/HIV coinfection shown by univariate analysis using chi-square test. Multivariate logistic regression analysis showed that shared needles or syringes in the past 3 mo (Odds ratio=3.121, 95% CI: 1.278-7.617, P<0.05) and syphilis infection (Odds ratio=2.914, 95% CI: 1.327-6.398, P<0.01) were significantly associated with HCV infection. No statistically significant association was found in univariate analysis between sexual behaviors and HCV/HIV coinfection. CONCLUSION: Shared needles and syringes in the past 3 mo and syphilis infection were significantly associated with HCV infection. Further sero-epidemiological prospective cohort studies should be conducted to clarify the impact of syphilis and high risk sexual behaviors on HCV transmission through unprotected sexual intercourse.


Assuntos
Infecções por HIV/epidemiologia , Hepatite C Crônica/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , China/epidemiologia , Comorbidade , Estudos Transversais , Coleta de Dados , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco
18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 38(5): 296-9, 2004 Sep.
Artigo em Zh | MEDLINE | ID: mdl-15498238

RESUMO

OBJECTIVE: To investigate prevalence of human immunodeficiency virus (HIV) infection and risk factors for its transmission among injection drug users (IDUs) in Liangshan Yizu Autonomous Prefecture of Sichuan Province, China. METHODS: A community-based survey was conducted to investigate demographic characteristics, pattern and frequency of sharing injection equipment, and sexual behaviors in IDUs. Blood samples were also collected from them to detect for antibodies against HIV and syphilis. RESULTS: A total of 379 subjects were recruited with informed consent for study through community outreach and peer recruiting methods. Their prevalence of HIV infection was 11.3% (43/379). Ethnicity, frequency of sharing syringes and cotton swab during the past three months and syphilis infection associated with HIV infection by univariate analysis using chi-square test. Multivariate logistic regression analysis showed odds ratio of frequency of sharing syringes for HIV infection during the past three months was 2.28 (95% CI 1.18 - 4.43), and that for syphilis infection 3.10 (95% CI 1.48 - 6.48). CONCLUSION: Frequency of sharing syringes during the past three months associated with syphilis and HIV infection.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Uso Comum de Agulhas e Seringas/efeitos adversos , Abuso de Substâncias por Via Intravenosa/virologia , Adolescente , Adulto , China/epidemiologia , Transmissão de Doença Infecciosa , Feminino , Humanos , Modelos Logísticos , Masculino , Prevalência , Comportamento Sexual
19.
PLoS One ; 8(4): e60306, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23589756

RESUMO

Viral vectors are engineered virus variants able to deliver nonviral genetic information into cells, usually by the same routes as the parental viruses. For several virus families, replication-competent vectors carrying reporter genes have become invaluable tools for easy and quantitative monitoring of replication and infection, and thus also for identifying antivirals and virus susceptible cells. For hepatitis B virus (HBV), a small enveloped DNA virus causing B-type hepatitis, such vectors are not available because insertions into its tiny 3.2 kb genome almost inevitably affect essential replication elements. HBV replicates by reverse transcription of the pregenomic (pg) RNA which is also required as bicistronic mRNA for the capsid (core) protein and the reverse transcriptase (Pol); their open reading frames (ORFs) overlap by some 150 basepairs. Translation of the downstream Pol ORF does not involve a conventional internal ribosome entry site (IRES). We reasoned that duplicating the overlap region and providing artificial IRES control for translation of both Pol and an in-between inserted transgene might yield a functional tricistronic pgRNA, without interfering with envelope protein expression. As IRESs we used a 22 nucleotide element termed Rbm3 IRES to minimize genome size increase. Model plasmids confirmed its activity even in tricistronic arrangements. Analogous plasmids for complete HBV genomes carrying 399 bp and 720 bp transgenes for blasticidin resistance (BsdR) and humanized Renilla green fluorescent protein (hrGFP) produced core and envelope proteins like wild-type HBV; while the hrGFP vector replicated poorly, the BsdR vector generated around 40% as much replicative DNA as wild-type HBV. Both vectors, however, formed enveloped virions which were infectious for HBV-susceptible HepaRG cells. Because numerous reporter and effector genes with sizes of around 500 bp or less are available, the new HBV vectors should become highly useful tools to better understand, and combat, this important pathogen.


Assuntos
Produtos do Gene pol/genética , Produtos do Gene pol/metabolismo , Vetores Genéticos/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Transgenes , Replicação Viral/genética , Linhagem Celular , Regulação Viral da Expressão Gênica , Ordem dos Genes , Genes Reporter , Genoma Viral , Humanos , Transporte Proteico , RNA Viral/genética , RNA Viral/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Vírion/fisiologia
20.
Zhonghua Liu Xing Bing Xue Za Zhi ; 27(4): 293-7, 2006 Apr.
Artigo em Zh | MEDLINE | ID: mdl-16875529

RESUMO

OBJECTIVE: To study the rate of human immunodeficiency virus (HIV) seroconversion, HIV transmission and related risk factors among injecting drug users (IDUs) in an area of Sichuan province. METHODS: In November 2002, a community-based baseline survey was conducted to recruit 333 HIV-seronegative IDUs for a prospective cohort study in Xichang county of Sichuan province, China. Follow-up visits were carried out every 6 months to study the situation of drug use, sexual behaviors of the IDUs and blood specimens were collected to test for antibodies against HIV and syphilis. RESULTS: During a 24-month follow-up period, cohort retention rate and HIV incidence were 75.7% and 2.53 per 100 person-years [95% confidence interval (CI): 1.10-3.97)], respectively. Multivariate Poisson regression model showed that risk factors which were significantly associated with HIV seroconversion would include: ethnicity (RR = 12.42; 95% CI: 2.72-56.74, P = 0.0012) and needle or syringe sharing in the past 3 months (RR = 4.06; 95% CI: 1.29-12.81, P = 0.0168). Syphilis seroconversion in this cohort was 4.71 per 100 person-years (95% CI: 2.59-6.82). In multivariate Poisson regression being female (RR = 4.42; 95% CI: 1.78-10.99, P = 0.0014) appeared to be the only factor which was significantly associated with syphilis seroconversion. CONCLUSION: Our study results showed that there was a rapid transmission of HIV and syphilis among IDUs in Sichuan province, suggesting that effective intervention should be urgently taken.


Assuntos
Soropositividade para HIV/imunologia , Abuso de Substâncias por Via Intravenosa , Sífilis/imunologia , Estudos de Coortes , Soropositividade para HIV/transmissão , Humanos , Estudos Prospectivos , Fatores de Risco , Comportamento Sexual , Sífilis/transmissão
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