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1.
Adv Exp Med Biol ; 1391: 275-309, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36472828

RESUMO

Male infertility is linked to several environmental and mutagenic factors. Most of these factors, i.e., lifestyle, radiations, and chemical contaminations, work on the fundamental principles of physics, chemistry, and biology. Principally, it may induce oxidative stress (OS) and produce free radicals within the cells. The negative effect of OS may enhance the reactive oxygen species (ROS) levels in male reproductive organs and impair basic functions in a couple's fertility. Evidence suggests that infertile men have significantly increased ROS levels and a reduced antioxidant capacity compared with fertile men. Although, basic spermatic function and fertilizing capacity depend on a delicate balance between physiological activity of ROS and antioxidants to protect from cellular oxidative injury in sperm, that is essential to achieve pregnancy. The ideal oxidation-reduction (REDOX) equilibrium requires a maintenance of a range of ROS concentrations and modulation of antioxidants. For this reason, the chapter focuses on the effects of ROS in sperm functions and the current concepts regarding the benefits of medical management in men with diminished fertility and amelioration of the effect to improve sperm function. Also, this evidence-based study suggests an increasing rate of infertility that poses a global challenge for human health, urging the need of health care professionals to offer a correct diagnosis, comprehension of the process, and an individualized management of the patients.


Assuntos
Antioxidantes , Infertilidade Masculina , Masculino , Humanos , Antioxidantes/uso terapêutico , Sêmen , Estresse Oxidativo
2.
Insects ; 11(2)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32024204

RESUMO

The first records of outbreaks of the Pine Spittle bug Ocoaxo assimilis Walker were recently identified from Puebla, Mexico, which promoted more than 2600 ha of forest foliar fall. Beyond the taxonomic and distribution information of this species, the basic traits of its biology remain unknown. This study aims to describe some biological aspects of O. assimilis, in a natural pine forest at Nicolás Bravo, Puebla (NB). Using morphological characteristics and a phylogenetic analysis of a fragment of cytochrome oxidase subunit I mtDNA (COI), immature instars with adults were studied; the instar number was determined by means of a multivariate analysis of 19 morphological characteristics of 121 specimens. The systematic sampling to evaluate the occurrence of nymphal specimens during a year, plus host selection experiments, allowed for determination of the abundance over time, voltism, and host preferences. Phylogenetic analysis of the COI supported that both nymphs and adults collected in NB correspond to O. assimilis. Principal coordinate analysis supported the existence of five nymphal stages. Field sampling and host selection experiments indicated that this species displays a single generation per year, is associated with the rainy season, and that specimens from the three first nymphal stages feed on roots of eight host species (one grass, four herbaceous species, one bush, and two trees). From the fourth instar, the insects feed on pine roots to complete their development, and when they are adults, they migrate to needles of young or mature pine stands of Pinus pseudostrobus to feed and reproduce.

3.
Educ. med. super ; 33(2): e1723, abr.-jun. 2019.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1089911

RESUMO

En los últimos años ha surgido la utilización del portafolio o carpeta como herramienta en los procesos formativos, al adoptarse una nueva y renovada visión sobre la enseñanza, el aprendizaje desarrollador y la evaluación educativa. El objetivo de este artículo es evaluar la competencia del uso del portafolio en el pregrado de Ciencias Médicas. Se demostró que en las universidades donde se utilizaba el portafolio, este favorecía el desarrollo profesional de los estudiantes, lo que propiciaba el dominio de competencias clínicas, y el desarrollo de actitudes como la responsabilidad y la sistematicidad; implicaba la documentación del aprendizaje y la recopilación de evidencias; y permitía la retroalimentación del desempeño del alumno. Aunque en los escenarios cubanos no se encontraron evidencias del empleo del portafolio, ya existen experiencias en varias latitudes que dan cuenta de los beneficios potenciales que esta herramienta está generando en el ámbito universitario, por lo que puede ser una buena opción o alternativa de evaluación(AU)


In recent years, the usage of the portfolio or folder as a tool in training processes has emerged as a new and renewed vision has been adopted regarding teaching, developing learning and educational evaluation. The objective of this article is to assess the competence associated to the usage of the portfolio in the undergraduate level of medical sciences. It was shown that, in the universities where the portfolio was used, it favored the students' professional development, which led to the mastery of clinical skills and the development of attitudes such as responsibility and systematicity; it involved the documentation of learning and the collection of evidence; and allowed feedback on student performance. Although there was no evidence of the usage of the portfolio in Cuban settings, there are already experiences in several sites that account for the potential benefits that this tool is generating in the university context, so it can be a good option or alternative for evaluation(AU)


Assuntos
Humanos , Avaliação Educacional , Retroalimentação , Aprendizagem
4.
Pediatr. (Asunción) ; 46(3)Set-Dic 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1506994

RESUMO

La leche materna es el alimento que provee al niño desde su nacimiento de todos los nutrientes que necesita para su crecimiento y desarrollo físico y psicológico. Su efecto sobre el tejido dental ha sido objeto de controversias, ya que se ha visto que actúa sobre la mineralización del esmalte y se ha asociado a caries de la infancia temprana. La leche humana tiene diversos componentes protectores para el esmalte dental pero al mismo tiempo contiene factores que pueden generar la pérdida de minerales. El propósito de esta revisión es exponer los elementos que producen la desmineralización y la remineralización del esmalte y proponer algunas medidas que apoyen la integridad de este tejido, así como recomendar la lactancia materna como la alimentación principal que el infante debe recibir durante el primer año de vida. La leche humana tiene diversas proteínas y elementos que ayudan en el proceso de desmineralización y remineralización del esmalte dental de la primera dentición. Se puede concluir que, la leche materna es el alimento ideal para los niños en los primeros años de vida. Por lo que hay que promover la lactancia materna como el método preferido para alimentar a los bebés. Se debe implementar la higiene desde que el primer diente erupciona en boca. Esta medida evitará que el posible efecto desmineralizante de la leche ejerza un efecto irreversible sobre el esmalte dental. Es conveniente orientar a las madres sobre el almacenamiento de la leche materna de tal manera que al ser consumida por el niño, no se encuentre acidificada, y no produzca un efecto dañino sobre el esmalte.


Breast milk provides the child of all the nutrients he needs for his growth and physical and psychological development beginning at birth. Its effect on dental tissue has been the subject of controversy, since it has been seen to act on the mineralization of enamel and has been associated with early childhood caries. Human milk has various protective components for tooth enamel but at the same time it contains factors that can cause the loss of minerals. The purpose of this review is to review the elements that produce the demineralization and remineralization of enamel and propose some measures that support the integrity of this tissue, as well as to recommend breastfeeding as the main feeding source that the infant should receive during the first year of life. Human milk has various proteins and elements that help in the process of demineralization and remineralization of the tooth enamel of first dentition. It can be concluded that, breast milk is the ideal food for children during the first years of life. Therefore, breastfeeding should be promoted as the preferred method of feeding babies. Oral hygiene should be implemented as soon as the first tooth erupts. This measure will prevent the possible demineralizing effect of milk from exerting an irreversible effect on tooth enamel. It is advisable to guide mothers on the storage of breast milk so that when consumed by the child, it is not acidified, and does not produce harmful effects on the enamel.

5.
Interciencia ; Interciencia;34(1): 25-33, ene. 2009. ilus, graf, mapas, tab
Artigo em Espanhol | LILACS | ID: lil-630711

RESUMO

En el presente trabajo se estudiaron 67 especies de hongos comestibles silvestres, 65 de ellas comercializadas en cuatro mercados regionales y varias en comunidades rurales, todas en la región de la Sierra Nevada, ubicada ésta en parte de las entidades del Estado de México, Puebla y Tlaxcala, al E y NE de la Ciudad de México. Se determinó el valor diferencial de importancia etnomicológica de las especies identificadas, por medio de la medición del valor de venta, así como de la presencia y la temporalidad de los hongos en los mercados, a lo largo de un año, en 1998. Se registró la preferencia de los hongos comestibles en una encuesta en 10 comunidades de la región, durante 1999. De los hongos considerados, Hebeloma fastibile fue la especie con mayor valor de importancia etnomicológica en los mercados y Lyophyllum decastes en las comunidades.


In this study, 67 species of wild edible mushrooms were studied, 65 of them were sold in four regional markets and some of them in communities, all on the Sierra Nevada found in the states of Mexico, Puebla, and Tlaxcala, at E and NE of Mexico City. The differential value of ethnomycological importance of the identified species was determined in terms of selling price as well as the presence and seasonality of the mushrooms, throughout one year, in 1998. Also, preference for the edible mushrooms mentioned was recorded through a survey of 10 communities in this region, during 1999. Of the mushrooms identified, Hebeloma fastibile was the species of highest value in terms of ethnomycological importance in the markets and Lyophyllum decastes was in the communities.


Contribuição ao conhecimento etnomicológico dos cogumelos comestiveis silvestres de mercados regionais e comunidades da Serra Nevada (México).


No presente trabalho se estudaram 67 espécies de cogumelos comestíveis silvestres, 65 delas comercializadas em quatro mercados regionais e varias em comunidades rurais, todas na região da Serra Nevada, situada esta em parte das entidades do Estado de México, Puebla e Tlaxcala, al E e NE da Cidade do México. Determinou-se o valor diferencial de importância etnomicológica das espécies identificadas, por meio da medição do valor de venda, assim como da presença e a temporalidade dos cogumelos nos mercados, ao longo de um ano, em 1998. Registrou-se a preferência dos cogumelos comestíveis em uma encosta em 10 comunidades da região, durante 1999. Dos cogumelos considerados, Hebeloma fastibile foi a espécie com maior valor de importância etnomicológica nos mercados e Lyophyllum decastes nas comunidades.

6.
Rev Latinoam Microbiol ; 47(3-4): 76-81, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17061531

RESUMO

A multitude of different polymerase chain reactions (PCRs) have been described for detection and typing of Herpes simplex virus (HSV). This paper compares two PCRs coupled to enzymatic restriction (PCR/RFLP) to detect and type HSV. A primers set was designed to amplify a HSV DNA fragment from UL30 and UL 15 genes. Typing was done by restriction of the UL30 and UL15 amplicons with Ava II and Hpa II enzymes, respectively. This strategy was tested with two reference strains (HSV-1 McIntyre, and HSV-2 G), and 47 clinical HSV isolates. Both PCRs produced the expected amplicons (a 492 bp UL30, and 305 bp UL15). The restriction of both amplicons clearly differentiated HSV- from HSV-2, and produced equal results. Thirty one (66%) of the isolates were identified as HSV-1, and the other 16 (34%), as HSV-2. Most of the HSV-1 isolates (27/31) were from orofacial and thoracic lesions; and also, one half of the HSV-2 isolates (8/16) were from the same anatomical regions. Our results showed that either of the two PCR/RFLP could be used to detect and type HSV. Furthermore, our results of the anatomical site of HSV-1 and HSV-2 infections are consistent with previous reports which have shown changes in the classical anatomical localization of herpesvirus infections.


Assuntos
Herpes Simples/virologia , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 2/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Virologia/métodos , Animais , Chlorocebus aethiops , DNA Viral/isolamento & purificação , Herpes Genital/virologia , Herpesvirus Humano 1/classificação , Herpesvirus Humano 2/classificação , Humanos , Células Vero
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