Análisis de la sensibilidad barorefleja arterial mediante la aplicación de fenilefrina y nitroprusiato sódico en pacientes con sospecha de sincope neurocardiogenico

El síncope neurocardiogénico (SNC) se caracteriza por una pérdida súbita de la conciencia y del tono postural con rápida recuperación posterior y sin secuelas neurológicas aparentes. El SNC es uno de los motivos de consulta mas frecuentes en la práctica clínica diaria. Cerca del 30% de la población general tiene un episodio de síncope al menos una vez en la vida y cerca del 3% de la población tiene episodios recurrentes. Aunque los mecanismos fisiopatológicos que median el SNC no están completamente esclarecidos, la condición clínica al momento del síncope (hipotensión con o sin bradicardia) ha sugerido una fuerte relación con anormalidades del sistema nervioso autónomo. En situaciones normales el ortostatismo desencadena ciertos ajustes hemodinámicos, tales como aumento de la frecuencia cardiaca, contractilidad miocárdica y del tono vascular con el objetivo de estabilizar la presión de perfusión cerebral. Esta respuesta está mediada por la activación de baroreceptores arteriales y cardiopulmonares los cuales censan los cambios de la presión arterial y venosa central generando cambios en la frecuencia cardiaca y vasoconstricción. Se cree que la alteración en la sensibilidad de estos baroreceptores a los cambios de presión arterial es un potencial mecanismo para el desarrollo del SNC5, pero los resultados reportados hasta el momento apoyando esta hipótesis aún son inconsistentes. El objetivo de este estudio fue evaluar la sensibilidad barorefleja arterial mediante la aplicación de dos sustancias vasoactivas (fenilefrina y nitroprusiato de sodio), en pacientes con sospecha clínica de SNC asistentes al servicio de fisiología autonómica de la Fundación Cardiovascular de Colombia para la realización de prueba de mesa basculante (PMB). Salud UIS 2008; 40: 163-16

Análisis de la sensibilidad barorefleja arterial mediante la aplicación de fenilefrina y nitroprusiato sódico en pacientes con sospecha de sincope neurocardiogenico

El síncope neurocardiogénico (SNC) se caracteriza por una pérdida súbita de la conciencia y del tono postural con rápida recuperación posterior y sin secuelas neurológicas aparentes. El SNC es uno de los motivos de consulta mas frecuentes en la práctica clínica diaria. Cerca del 30% de la población general tiene un episodio de síncope al menos una vez en la vida y cerca del 3% de la población tiene episodios recurrentes. Aunque los mecanismos fisiopatológicos que median el SNC no están completamente esclarecidos, la condición clínica al momento del síncope (hipotensión con o sin bradicardia) ha sugerido una fuerte relación con anormalidades del sistema nervioso autónomo. En situaciones normales el ortostatismo desencadena ciertos ajustes hemodinámicos, tales como aumento de la frecuencia cardiaca, contractilidad miocárdica y del tono vascular con el objetivo de estabilizar la presión de perfusión cerebral. Esta respuesta está mediada por la activación de baroreceptores arteriales y cardiopulmonares los cuales censan los cambios de la presión arterial y venosa central generando cambios en la frecuencia cardiaca y vasoconstricción. Se cree que la alteración en la sensibilidad de estos baroreceptores a los cambios de presión arterial es un potencial mecanismo para el desarrollo del SNC5, pero los resultados reportados hasta el momento apoyando esta hipótesis aún son inconsistentes. El objetivo de este estudio fue evaluar la sensibilidad barorefleja arterial mediante la aplicación de dos sustancias vasoactivas (fenilefrina y nitroprusiato de sodio), en pacientes con sospecha clínica de SNC asistentes al servicio de fisiología autonómica de la Fundación Cardiovascular de Colombia para la realización de prueba de mesa basculante (PMB). Salud UIS 2008; 40: 163-16

Human oral viruses are personal, persistent and gender-consistent.

Viruses are the most abundant members of the human oral microbiome, yet relatively little is known about their biodiversity in humans. To improve our understanding of the DNA viruses that inhabit the human oral cavity, we examined saliva from a cohort of eight unrelated subjects over a 60-day period. Each subject was examined at 11 time points to characterize longitudinal differences in human oral viruses. Our primary goals were to determine whether oral viruses were specific to individuals and whether viral genotypes persisted over time. We found a subset of homologous viral genotypes across all subjects and time points studied, suggesting that certain genotypes may be ubiquitous among healthy human subjects. We also found significant associations between viral genotypes and individual subjects, indicating that viruses are a highly personalized feature of the healthy human oral microbiome. Many of these oral viruses were not transient members of the oral ecosystem, as demonstrated by the persistence of certain viruses throughout the entire 60-day study period. As has previously been demonstrated for bacteria and fungi, membership in the oral viral community was significantly associated with the sex of each subject. Similar characteristics of personalized, sex-specific microflora could not be identified for oral bacterial communities based on 16S rRNA. Our findings that many viruses are stable and individual-specific members of the oral ecosystem suggest that viruses have an important role in the human oral ecosystem

Prevalence, concordance and determinants of human papillomavirus infection among heterosexual partners in a rural region in central Mexico

Background: Although human papillomavirus (HPV) infection in heterosexual couples has been sparsely studied, it is relevant to understand disease burden and transmission mechanisms. The present study determined the prevalence and concordance of type-specific HPV infection as well as the determinants of infection in heterosexual couples in a rural area of Mexico. Methods: A cross-sectional study was conducted in 504 clinically healthy heterosexual couples from four municipalities in the State of Mexico, Mexico. HPV testing was performed using biotinylated L1 consensus primers and reverse line blot in cervical samples from women and in genital samples from men. Thirty-seven HPV types were detected, including high-risk oncogenic types and low-risk types. Multivariate logistic regression models were utilized to evaluate factors associated with HPV. Results: The prevalence of HPV infection was 20.5% in external male genitals and 13.7% in cervical samples. In 504 sexual couples participating in the study, concordance of HPV status was 79%; 34 partners (6.7%) were concurrently infected, and 21 out of 34 partners where both were HPV positive (61.8%) showed concordance for one or more HPV types. The principal risk factor associated with HPV DNA detection in men as well as women was the presence of HPV DNA in the respective regular sexual partner (OR = 5.15, 95% CI 3.01-8.82). In men, having a history of 10 or more sexual partners over their lifetime (OR 2.5, 95% CI 1.3 - 4.8) and having had sexual relations with prostitutes (OR 1.7, 95% CI 1.01 - 2.8) increased the likelihood of detecting HPV DNA. Conclusions: In heterosexual couples in rural regions in Mexico, the prevalence of HPV infection and type-specific concordance is high. High-risk sexual behaviors are strong determinants of HPV infection in men

Interaction of Copper-Based Nanoparticles to Soil, Terrestrial, and Aquatic Systems: Critical Review of the State of the Science and Future Perspectives

In the past two decades, increased production and usage of metallic nanoparticles (NPs) has inevitably increased their discharge into the different compartments of the environment, which ultimately paved the way for their uptake and accumulation in various trophic levels of the food chain. Due to these issues, several questions have been raised on the usage of NPs in everyday life and has become a matter of public health concern. Among the metallic NPs, Cu-based NPs have gained popularity due to their cost-effectiveness and multifarious promising uses. Several studies in the past represented the phytotoxicity of Cu-based NPs on plants. However, comprehensive knowledge is still lacking. Additionally, the impact of Cu-based NPs on soil organisms such as agriculturally important microbes, fungi, mycorrhiza, nematode, and earthworms are poorly studied. This review article critically analyses the literature data to achieve a more comprehensive knowledge on the toxicological profile of Cu-based NPs and increase our understanding of the effects of Cu-based NPs on aquatic and terrestrial plants as well as on soil microbial communities. The underlying mechanism of biotransformation of Cu-based NPs and the process of their penetration into plants has also been discussed herein. Overall, this review could provide valuable information to design rules and regulations for the safe disposal of Cu-based NPs into a sustainable environment

A note on "Origin of components in Chilean thermal waters" by Risacher et al. (2011)

Risacher et al. (2011) have presented voluminous data on thermal waters of Chile that is quite appreciable; however, their work still falls short on several counts. The most notable shortcoming of the work is the presentation and treatment of data. The interpretations are based on questionable premises (viz., extent of seawater intrusion) and considerations (viz., using average chemical composition of rock types for geochemical modeling, considering volcanic rocks as the only rock type in contact with the geothermal fluids) and assumptions not always substantiated by facts (with proper references) could have been corroborated. Use of Cl/Br ratio for discrimination purpose is unconvincing, considering the uncertainty in the measurement of low (<1 mg/L) Br concentration. (C) 2013 Elsevier Ltd. All rights reservedCONICYT, Chile PBCT PDA-0