Epidemiología molecular del VIH-1 en México

El Síndrome de Inmunodeficiencia Adquirida (SIDA), es considerada como una pandemia que al igual que otras enfermedades requiere del diagnóstico, vigilancia y tratamiento efectivos. En la actualidad ésta se encuentra en una fase impredecible e inestable, tan sólo en 1999 se infectaron 5.6 millones de individuos, llevando a un total global de 33.6 millones, se conoce que a finales de 1999 habrá cerca de 50 millones de individuos que han sido infectado con el VIH, de los cuales 16 millones ya han fallecido. En México, al igual que en el resto de los países del mundo, El VIH/SIDA se ha convertido en un serio problema de salud pública, con múltiples repercusiones psicológicas, sociales, éticas, morales, religiosas, económicas y políticas. Al 30 de septiembre de 1999, los casos diagnosticados en el país suman 40,743 casos de SIDA ya desarrollado, sin tomar en cuenta el 35% en el retraso en la notificación y el 18.5% en el subregistro, lo que nos da un total estimado de 62, 540 casos. Se estima que 187,621 están viviendo con el VIH sin haber presentado todavía las manifestaciones clínicas de la enfermedad

ALIMENTACIÓN: SU IMPACTO SOBRE EL SISTEMA INMUNE Y CÁNCER

Un sistema de medicina integral es necesario para el tratamiento del cáncer debido a que las actuales medidas aplicadas a pacientes con esta enfermedad están enfocadas principalmente en la administración de quimioterapia, radioterapia y anticuerpos monoclonales en diversos tipos de cáncer sin tomar en cuenta la participación del sistema psiconeuroinmunológico y nutrimental siendo estos los encargados del control de la homeostasis celular. En esta revisión estudiaremos los mecanismos que relacionan la alimentación con el sistema inmune y el desarrollo del cáncer, así como los mecanismos implicados en la generación de un tipo de células inmunosupresoras llamadas células T reguladoras que están relacionadas con el desarrollo y progresión tumoral. Abstract A comprehensive system of medicine needed to treat cancer because current measures to patients with this disease are focused mainly on chemotherapy, radiotherapy and monoclonal antibodies in various types of cancer regardless of system involvement psychoneuroimmunological and nutritional and these were responsible for the control of cellular homeostasis. In this review we will study the mechanisms that link nutrition to the immune system and cancer development, as well as the mechanisms involved in generating a type of immunosuppressive cells called regulatory T cells that are related to the development and progression. Palabras clave: Células T reguladoras, sistema inmune, cáncer, alimentación, NF-kB, inmunovigilancia, immunosurveillance.

CÉLULAS DENDRÍTICAS EN LA INMUNOPATOLOGÍA DEL VIRUS DE INMUNODEFICIENCIA HUMANA

En México, como en el resto de los países del mundo, el SIDA ha sido considerado como un serio problema de salud pública. El VIH-1 tiene la capacidad de infectar diversos tipos celulares: células T, macrófagos y células dendríticas (CD). Estas últimas, son cruciales en la defensa contra agentes infecciosos y juegan un papel importante en la patogénesis del virus, constituyen una de las primeras células en ser infectadas en mucosa periférica y están distribuidas en vagina,ectocervix y mucosa anal; permitiendo así el contacto con el VIH-1 durante la exposición sexual.Recientemente se ha demostrado que una proteína de membrana tipo II denominada DC-SIGN, participa en la unión del VIH-1 a las CD. Este receptor, es el responsable de mediar la infección a las células T a través de CD, utilizandolas como portadoras permitiendo que el virus tenga acceso a tejido linfático, su mayor sitio de replicación, contribuyendo de esta manera a la patogénesis del VIH/SIDA.Palabras clave: SIDA, VIH, Células dendríticas   AIDS, HIV, dendrtitic cel

Expression of CCR5, CXCR4 and DC-SIGN in Cervix of HIV-1 Heterosexually Infected Mexican Women

Background: A number of studies have demonstrated that receptor and co-receptor expression levels which may affect viral entry, promoting cervical HIV infection. The aim was to evaluate the expression levels of CCR5, CXCR4 and DC-SIGN mRNA in a sample of heterosexually HIV infected Mexican women. Methods: We enrolled twenty-six HIV heterosexual infected women attending a local infectious diseases medical unit. RNA was isolated from the cervix and gene expression analysis was performed using real-time PCR. Results: Expression rates for mRNA of CCR5 (median 1.82; range 0.003–2934) were higher than those observed for CXCR4 (0.79; 0.0061–3312) and DC-SIGN (0.33; 0.006–532) receptors (p < 0.05). A high correlation was found between the mRNA expression levels of these three receptors (rs = 0.52 to 0.85, p < 0.01). Conclusion: Levels of expression of the tested chemokine receptors in the cervix are different from each other and also vary from woman to woman, and seem to support the suggestion that chemokine receptor expression in genital tissues may be playing a role in the HIV transmission

Advantages of adipose tissue stem cells over CD34+ mobilization to decrease hepatic fibrosis in Wistar rats

Introduction and Objectives: Chronic liver inflammation may lead to hepatic cirrhosis, limiting its regenerative capacity. The clinical standard of care is transplantation, although stem cell therapy may be an alternative option. The study aim was to induce endogenous hematopoietic stem cells (HSCs) with granulocyte colony stimulating factor (G-CSF) and/or intravenous administration of adipose tissue-derived mesenchymal stem cells (MSCs) to decrease hepatic fibrosis in an experimental model. Material and methods: A liver fibrosis model was developed with femaleWistar rats via multiple intraperitoneal doses of carbon tetrachloride. Three rats were selected to confirm cirrhosis, and the rest were set into experimental groups to evaluate single and combined therapies of G-CSF-stimulated HSC mobilization and intravenous MSC administration. Results: Treatment with MSCs and G-CSF significantly improved alanine amino transferase levels, while treatment with G-CSF, MSCs, and G-CSF + MSCs decreased aspartate amino transferase levels. Hepatocyte growth factor (HGF) and interleukin 10 levels increased with MSC treatment. Transforming growth factor levels were lower with MSC treatment. Interleukin 1 and tumor necrosis factor alpha levels decreased in all treated groups. Histopathology showed that MSCs and G-CSF reduced liver fibrosis from F4 to F2. Conclusions: MSC treatment improves liver function, decreases hepatic fibrosis, and plays an antiinflammatory role;it promotes HGF levels and increased proliferating cell nuclear antigen when followed by MSC treatment mobilization using G-CSF. When these therapies were combined, however, fibrosis improvement was less evident

Infection and coinfection by human papillomavirus, Epstein–Barr virus and Merkel cell polyomavirus in patients with squamous cell carcinoma of the larynx: a retrospective study

Background Human papillomavirus (HPV) is recognized as an important risk factor for laryngeal carcinogenesis. Although HPV-16 and 18 have been strongly implicated, the presence of other high-risk HPV (HR-HPV) genotypes or the coinfection with Epstein-Barr virus (EBV) or Merkel cell polyomavirus (MCPV) may increase the risk, but their etiological association has not been definitively established. Methods We characterized the genotype-specific HPV and the frequency of EBV and MCPV infections through the detection of their DNA in 195 laryngeal specimens of squamous cell carcinoma (SCC) histologically confirmed. Results HPV DNA was detected in 93 (47.7%) specimens. HPV-11 was the most frequent with 68 cases (73.1%), and HPV-52 was the most frequently HR-HPV found with 51 cases, which corresponds to 54.8% of all HPV-positive specimens. EBV DNA was detected in 54 (27.7%) tumor tissue specimens of which 25 (46.3%) were in coinfection with HPV. MCPV DNA was detected only in 11 (5.6%) cases of which 5 (45.4%) were in coinfection with an HR-HPV. No association between the presence of DNA of the three examined viruses and the patient smoking habits, alcohol consumption, age, the keratinization status, differentiation grade, or localization of the tumor in the larynx were found. Discussion HPV-52 was the most prevalent HR-HPV, which may suggest that this and other genotypes in addition to HPV-16 and 18 could be considered for prophylaxis. However, further studies including non-cancer larynx cases and the evaluation of other molecular markers and viral co-infection mechanisms are needed to determine the role of the different HR-HPV genotypes, EBV, and MCPV in the etiology of SCC of the larynx