Molecular Tools for Gene Analysis in Fission Yeast

Schizosaccharomyces pombe or fission yeast has been called micromammal due to the potential application of the knowledge derived from the yeast in the physiology of higher eukaryotes. Fission yeast has been consolidated as an excellent model for the study of highly conserved cellular processes. The possibility of using haploid or diploid strains facilitates the analysis of the dominant or recessive phenotype of an allele as well as its function, making it a model of first choice for the development of any investigation in eukaryotes cells. With a growing community that employs fission yeast as a model system for the study of numerous cellular processes, it has motivated the simultaneous development of molecular tools that facilitate the study of genes and proteins in the yeast. In this review, we present the most used molecular techniques in fission yeast for the analysis of genes, its characterization, as well as the determination of its function

Detection of hepatitis C virus RNA in saliva of patients with active infection not associated with periodontal or liver disease severity

BACKGROUND: Hepatitis C virus (HCV) is mainly transmitted by parenteral route, being blood transfusion and intravenous drug use the most frequent risk factors. However, it has been suggested that there are other routes of transmission. There are several studies where HCV RNA has been detected in saliva of patients infected with HCV, and epidemiological studies have proposed the dental treatments as possible risk factors for HCV transmission. The purpose of this study was to detect the presence of HCV RNA in saliva of patients with active infection and associating with periodontal or liver disease. METHODS: Patients with quantifiable HCV-RNA in serum were enrolled in the study. Periodontal disease was assessed using the modified gingival index (MGI). Presence of dental plaque was assessed with the use of disclosing tablets. Patients were clinically and laboratory evaluated to identify the stage of liver disease, the HCV RNA was determinate in saliva by nested RT-PCR. To determine associations between different parameters univariate and multivariate analysis were used. RESULTS: A total of 45 patients were included. Of these patients, 21 (46.6%) had hepatitis, 23 (51.1%) had cirrhosis and one patient (2.4%) presented hepatocellular carcinoma (HCC). Viral loads in serum ranged from 2.31–6.68 log IU/ml with a mean of 5.46 log IU/ml (95% CI 5.23–5.70). HCV RNA was positive in saliva of 29 patients (64.4%) and was not detected in 16 (35.6%). For univariate analysis three independent variables were associated with the detection of HCV-RNA in saliva: gender, viral load and dental plaque and multivariate analysis only one independent variable viral load >5.17 log IU/mL remained significantly associated with the detection of HCV in saliva (p = 0.0002). A statistical difference was observed when viral load was analyzed, log 5.85 IU/mL (95% CI 5.67–6.02) for patients with HCV in saliva vs. log 4.77 IU/mL (95% CI 4.35–5.19) for patients without HCV in saliva (p = 0.0001). The detection of HCV-RNA in saliva was more frequent in patients with relatively high serum viral loads. CONCLUSION: HCV-RNA in saliva was associated with the level of serum viral load but not with periodontal or liver disease severity

Hepatitis C virus infection in blood donors from the state of Puebla, Mexico

<p>Abstract</p> <p>Background</p> <p>Worldwide, 130 million persons are estimated to be infected with HCV. Puebla is the Mexican state with the highest mortality due to hepatic cirrhosis. Therefore, it is imperative to obtain epidemiological data on HCV infection in asymptomatic people of this region. The objective of present study was to analyze the prevalence of antibodies and genotypes of hepatitis C virus (HCV) in blood donors from Puebla, Mexico.</p> <p>Results</p> <p>The overall prevalence was 0.84% (515/61553). Distribution by region was: North, 0.86% (54/6270); Southeast, 1.04% (75/7197); Southwest, 0.93% (36/3852); and Central, 0.79% (350/44234). Ninety-six donors were enrolled for detection and genotyping of virus, from which 37 (38.5%) were HCV-RNA positive. Detected subtypes were: 1a (40.5%), 1b (27.0%), mixed 1a/1b (18.9%), undetermined genotype 1 (5.4%), 2a (2.7%), 2b (2.7%), and mixed 1a/2a (2.7%). All recovered donors with S/CO > 39 were HCV-RNA positive (11/11) and presented elevated ALT; in donors with S/CO < 39 HCV-RNA, positivity was of 30.4%; and 70% had normal values of ALT. The main risk factors associated with HCV infection were blood transfusion and surgery.</p> <p>Conclusions</p> <p>HCV prevalence of donors in Puebla is similar to other Mexican states. The most prevalent genotype is 1, of which subtype 1a is the most frequent.</p

Modulation of apoptosis by V protein mumps virus

<p>Abstract</p> <p>Background</p> <p>The Urabe AM9 vaccine strain of mumps virus contains two variants of V protein: VWT (of HN-A1081 viral population) and VGly (of HN-G1081). The V protein is a promoting factor of viral replication by blocking the IFN antiviral pathway.</p> <p>Findings</p> <p>We studied the relationship between V protein variants and IFN-α2b-induced apoptosis. V proteins decrease activation of the extrinsic IFN-α2b-induced apoptotic pathway monitored by the caspase 8 activity, being the effect greater with the VWT protein. Both V proteins decrease the activity of caspase 9 of the intrinsic apoptotic pathway. In a system without IFN, the VWT and VGly proteins expression promotes activation of caspases 3 and 7. However, when the cellular system was stimulated with IFN-α, this activity decreased partially. TUNEL assay shows that for treatment with IFN-α and ibuprofen of cervical adenocarcinoma cells there is nuclear DNA fragmentation but the V protein expression reduces this process.</p> <p>Conclusions</p> <p>The reduction in the levels of caspases and DNA fragmentation, suggesting that V protein, particularly VWT protein of Urabe AM9 vaccine strain, modulates apoptosis. In addition, the VWT protein shows a protective role for cell proliferation in the presence of antiproliferative signals.</p

Distribución heterogénea de la prevalencia de anticuerpos contra Trypanosoma cruzi en donadores de sangre en Puebla, México

Objetivo. Identificar la seroprevalencia de anticuerpos anti Trypanosoma cruzi (Ac anti-T. cruzi) en donadores de sangre que habitan en ámbito rural y suburbano, así como las regiones del estado de mayor riesgo y factores asociados. Material y métodos. Estudio transversal realizado de enero a diciembre de 2003. Se analizaron 2 489 donadores de sangre reclutados en 10 puestos de sangrado del Instituto Mexicano del Seguro Social (IMSS) distribuidos en las siete regiones económicas del estado de Puebla, México. Se determinó la seroprevalencia mediante las pruebas serológicas obligatorias del panel viral y, además, para T. cruzi, región de reclutamiento y de origen de los donadores. Resultados. La seroprevalencia de Ac anti-T. cruzi fue de 1.24% (31/2 489) comparable con la obtenida para el virus de la hepatitis C (1.5%) y por arriba de la del virus de la inmunodeficiencia humana (0.4%) y del antígeno de superficie del virus de la hepatitis B (0.3%). Las regiones de Tehuacán- Sierra Negra y Mixteca fueron las de mayor riesgo con seroprevalencias, por el origen del donador, de 2.6% para T. cruzi, mientras que en los originarios de las regiones Sierra nororiental y Angelópolis no se detectaron casos positivos. Se observó asociación entre ser seropositivo y mayor de 40 años y ser originario de las regiones de Tehuacán-Sierra Negra y Mixteca. Conclusiones. La distribución de seroprevalencia a T. cruzi es heterogénea, oscila desde 0% hasta 2.6%, y se reconoce a Tehuacán-Sierra Negra y Mixteca como las regiones de mayor riesgo

Distribución heterogénea de la prevalencia de anticuerpos contra Trypanosoma cruzi en donadores de sangre en Puebla, México Heterogeneous distribution of the prevalence of anti-Trypanosoma cruzi antibodies among blood donors in the State of Puebla, Mexico

OBJETIVO: Identificar la seroprevalencia de anticuerpos anti Trypanosoma cruzi (Ac anti-T. cruzi) en donadores de sangre que habitan en ámbito rural y suburbano, así como las regiones del estado de mayor riesgo y factores asociados. MATERIAL Y MÉTODOS: Estudio transversal realizado de enero a diciembre de 2003. Se analizaron 2 489 donadores de sangre reclutados en 10 puestos de sangrado del Instituto Mexicano del Seguro Social (IMSS) distribuidos en las siete regiones económicas del estado de Puebla, México. Se determinó la seroprevalencia mediante las pruebas serológicas obligatorias del panel viral y, además, para T. cruzi, región de reclutamiento y de origen de los donadores. RESULTADOS: La seroprevalencia de Ac anti-T. cruzi fue de 1.24% (31/2 489) comparable con la obtenida para el virus de la hepatitis C (1.5%) y por arriba de la del virus de la inmunodeficiencia humana (0.4%) y del antígeno de superficie del virus de la hepatitis B (0.3%). Las regiones de Tehuacán-Sierra Negra y Mixteca fueron las de mayor riesgo con seroprevalencias, por el origen del donador, de 2.6% para T. cruzi, mientras que en los originarios de las regiones Sierra nororiental y Angelópolis no se detectaron casos positivos. Se observó asociación entre ser seropositivo y mayor de 40 años y ser originario de las regiones de Tehuacán-Sierra Negra y Mixteca. CONCLUSIONES: La distribución de seroprevalencia a T. cruzi es heterogénea, oscila desde 0% hasta 2.6%, y se reconoce a Tehuacán-Sierra Negra y Mixteca como las regiones de mayor riesgo.OBJECTIVE: To determine the seroprevalence and associated factors, of antibodies against Trypanosoma cruzi (T. cruzi Ab) among blood donors living in rural and suburban areas and risk regions. MATERIAL AND METHODS: A cross-sectional study was conducted from January to December 2003, in 2489 blood donors of seven regions of Puebla, who were evaluated for mandatory viral and T. cruzi serological tests using validated procedures RESULTS: The seroprevalence for T. cruzi Ab was 1.24% (31/2489), similar to hepatitis C (HVC) (1.5%) and higher than human immunodeficiency virus (HIV) (0.4%) and hepatitis B (HVB) (0.3%). The highest seroprevalences were observed in the regions of Tehuacan-Sierra Negra and Mixteca, up to 2.6%, while in Sierra nororiental and Angelopolis no positive blood donors were identified. A positive association was observed between seropositivity and being older than forty years and being born and raised in Tehuacan-Sierra Negra and Mixteca. CONCLUSIONS: T.cruzi seroprevalence distribution is heterogeneous, from 0% to 2.6%, with higher seroprevalences in the regions of Tehuacan-Sierra Negra and Mixteca