Modelo de competencia docente del profesor de medicina en la UNAM

El estudio presenta un modelo de competencia docente del profesor de medicina. Fue generado a partir de un modelo conceptual preexistente: a) dicho modelo se sometió al juicio de expertos quienes seleccionaron las competencias de mayor impacto; b) se construyó un perfil de competencias; c) se generó un instrumento basado en la opinión de los estudiantes y otro de autoevaluación; d) ambos fueron validados por 18 expertos en evaluación; e) se aplicó a 2,281 estudiantes y 107 profesores, obteniendo un comportamiento psicométrico adecuado que permitió establecer un modelo acorde a las tendencias actuales en evaluación del desempeño docente

MoS2-Carbon Nanodots as a New Electrochemiluminescence Platform for Breast Cancer Biomarker Detection

In this work, we present the combination of two different types of nanomaterials, 2D molybdenum disulfide nanosheets (MoS2-NS) and zero-dimensional carbon nanodots (CDs), for the development of a new electrochemiluminescence (ECL) platform for the early detection and quantification of the biomarker human epidermal growth factor receptor 2 (HER2), whose overexpression is associated with breast cancer. MoS2-NS are used as an immobilization platform for the thiolated aptamer, which can recognize the HER2 epitope peptide with high affinity, and CDs act as coreactants of the anodic oxidation of the luminophore [Ru(bpy)3]2+. The HER2 biomarker is detected by changes in the ECL signal of the [Ru(bpy)3]2+/CD system, with a low detection limit of 1.84 fg/mL and a wide linear range. The proposed method has been successfully applied to detect the HER2 biomarker in human serum samplesThis work has been financially supported by the Spanish Ministry of Economy and Competitiveness (PID2020-116728RB-I00, PID2020-116661RB-I00, CTQ2015-71955-REDT (ELECTROBIONET)), Community of Madrid (TRANSNANOAVANSENS, S2018/NMT-4349, and FotoArt (P2018/NMT4367), project S2018/NMT-4291 TEC2SPACE), MINECO (project CSIC13-4E-1794) and EU (FEDER, FSE). IMDEA Nanociencia receives support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, Grant CEX2020-001039-S)

Carbon nanodot–based electrogenerated chemiluminescence biosensor for miRNA-21 detection

A simple carbon nanodot–based electrogenerated chemiluminescence biosensor is described for sensitive and selective detection of microRNA-21 (miRNA-21), a biomarker of several pathologies including cardiovascular diseases (CVDs). The photoluminescent carbon nanodots (CNDs) were obtained using a new synthesis method, simply by treating tiger nut milk in a microwave reactor. The synthesis is environmentally friendly, simple, and efficient. The optical properties and morphological characteristics of the CNDs were exhaustively investigated, confirming that they have oxygen and nitrogen functional groups on their surfaces and exhibit excitation-dependent fluorescence emission, as well as photostability. They act as co-reactant agents in the anodic electrochemiluminescence (ECL) of [Ru(bpy)3]2+, producing different signals for the probe (single-stranded DNA) and the hybridized target (double-stranded DNA). These results paved the way for the development of a sensitive ECL biosensor for the detection of miRNA-21. This was developed by immobilization of a thiolated oligonucleotide, fully complementary to the miRNA-21 sequence, on the disposable gold electrode. The target miRNA-21 was hybridized with the probe on the electrode surface, and the hybridization was detected by the enhancement of the [Ru(bpy)3]2+/DNA ECL signal using CNDs. The biosensor shows a linear response to miRNA-21 concentration up to 100.0 pM with a detection limit of 0.721 fM. The method does not require complex labeling steps, and has a rapid response. It was successfully used to detect miRNA-21 directly in serum samples from heart failure patients without previous RNA extraction neither amplification processThis study is funded by the Comunidad Autónoma de Madrid (Spain) projects (TRANSNANOAVANSENS, S2018/NMT-4349, CAM/B2017/BMD-3686) and Ministerio de Economía, Industria y Competitividad (Spanish Government) projects: CTQ2015-71955-REDT (ELECTROBIONET), CTQ2014-53334-C2-1-R and PID2020-116728RB-I0

A ingestão de álcool e qualidade do sêmen em homens jovens saudáveis

Over the past 50 years it has been suggested a worldwide decline in human semen quality, probably being lifestyles one of the main factors concerned. Our objectives are to describe semen quality and alcohol consumption in young university students and to explore the associations between alcohol intake and semen quality in young healthy men. A cross-sectional study was carried out between 2010 and 2011 in the Murcia Region (Spain) and included healthy young university students between 18-23 years of age. Two hundred and nine men completed questionnaires on lifestyle and diet, undertook a physical and andrological examination and provided a semen sample. Descriptive statistics are presented using untransformed data. Multiple linear regression analyses were performed to analyze the associations between alcohol intake and semen quality in young men. The median (interquartile range: IQR) values for semen parameters were 42.9 x 106/mL (IQR: 21.9-72.2 x 106/mL) for sperm concentration, 8.9 % (IQR: 6.0-13.9 %) for morphologically normal sperm, and 57.2 % (IQR: 50.7-63.8 %) for sperm motility (progessive and non-progressive). There were no significant associations between alcohol consumption and any sperm parameters. Our results do not support the hypothesis that alcohol intake is related with sperm quality parameters probably due to the low alcohol consumption range in our population of healthy, unselected young men. In conclusion, moderate alcohol consumption is not associated with semen quality in young university students of Murcia Region (Spain).En los últimos 50 años se ha sugerido una disminución global de la concentración espermática humana, siendo los hábitos de vida uno de los principales determinantes señalados. El objetivo de este estudio es describir el consumo de alcohol y la calidad seminal en jóvenes varones universitarios e investigar las asociaciones entre ambas características. Se trata de un estudio transversal que se llevó a cabo en la Región de Murcia (España) entre 2010 y 2011. Los participantes fueron jóvenes universitarios sanos entre 18 y 23 años. Doscientos nueve varones cumplimentaron cuestionarios sobre hábitos de vida y alimentación, se sometieron a un examen físico y andrológico y proporcionaron una muestra seminal. Los estadísticos descriptivos se muestran como datos crudos. Para analizar las asociaciones entre consumo de alcohol y calidad seminal se realizaron análisis de regresión lineal múltiple. Los valores de la mediana y rango intercuartil (RIC) de los parámetros seminales analizados fueron los siguientes: 42,9 x 106/mL (RIC: 21,9-72,2 x 106/mL) de concentración espermática, 8,9 % (RIC: 6,0-13,9 %) de espermatozoides morfológicamente normales, y 57,2 % (RIC: 50,7-63,8 %) de movilidad espermática (progresiva y no progresiva). No se encontraron asociaciones significativamente estadísticas entre el consumo de alcohol y los distintos parámetros seminales. Nuestros resultados no respaldan la hipótesis de que la ingesta de alcohol esté relacionada con la calidad seminal, probablemente debido al bajo rango de consumo de alcohol en nuestra población de estudio. En conclusión, el consumo moderado de alcohol no está relacionado con la calidad seminal en jóvenes universitarios sanos de la Región de Murcia.Nos últimos 50 anos tem sugerido uma diminuição global da concentração de esperma humano e os estilos de vida foram identificados com um dos principais determinantes. O objetivo deste estudo é descrever o consumo de álcool e a qualidade do sémen em jovens universitários e investigar as associações entre estas duas características. Trata-se de um estudo transversal realizado na Região de Múrcia (Espanha) entre 2010 e 2011. Os participantes foram estudantes universitários saudáveis, com idades compreendidas entre os 18 e os 23 anos. Duzentos e nove rapazes responderam aos questionários sobre hábitos de vida e alimentação; submeteram-se a um exame físico e andrológico e forneceram uma amostra de sémen. Os resultados da estatística descritiva foram apresentados com dados brutos. Para analisar as associações entre o consumo de álcool e a qualidade do sémen, realizou-se a análise através de regressão linear múltipla. Os valores de mediana e o intervalo interquartil (IQR) em parâmetros do sémen analisados foram os seguintes: 42,9 x 106/mL (IQR, 21,9-72,2 x 106/mL) de concentração de espermatozóides, de 8,9 % (IQR, 6,0-13,9 %) de espermatozóides morfologicamente normais e 57,2 % (IQR, 50,7-63,8 %) da motilidade de espermática (progressiva e não progressiva). Não foram encontradas associações estatisticamente significativas entre o consumo de álcool e os vários parâmetros do esperma. Os nossos resultados não apoiam a hipótese de que o consumo de álcool esteja relacionado com a qualidade do sémen, provavelmente devido ao baixo consumo de álcool na população em estudada. Conclui-se que o consumo moderado de álcool não está relacionado com a qualidade do sémen nos jovens saudáveis da universidade da Região de Murcia

Correlations between Different Heavy Metals in Diverse Body Fluids: Studies of Human Semen Quality

It has been hypothesized that exposure to heavy metals may impair male reproduction. To measure the effect produced by low doses of heavy metals on semen parameters, it is necessary to clarify in which body fluids those measurements must be performed. Sixty-one men attending infertility clinics participated in our study. Concentrations of lead, cadmium, and mercury were measured in whole blood, blood plasma, and seminal plasma using spectroanalytical and electrochemical methods. Semen analyses were performed according to World Health Organization criteria. For statistical analysis, Spearman's rank correlations, mean comparison tests, and discriminant analysis were calculated. Significant correlations between the measured concentrations of the three heavy metals in the same biological fluids were observed. However, no similar relationship was seen when comparing the concentrations in different body fluids of the same metal. According to our results and previous publications, seminal plasma might be the best body fluid for assessing impairment of human semen parameters

Relationships between heavy metal concentrations in three different body fluids and male reproductive parameters: a pilot study

<p>Abstract</p> <p>Background</p> <p>Animal studies have shown the reproductive toxicity of a number of heavy metals. Very few human observational studies have analyzed the relationship between male reproductive function and heavy metal concentrations in diverse biological fluids.</p> <p>Methods</p> <p>The current study assessed the associations between seminal and hormonal parameters and the concentration of the 3 most frequent heavy metal toxicants (lead, cadmium and mercury) in three different body fluids. Sixty one men attending infertility clinics that participated in a case-control study to explore the role of environmental toxins and lifestyles on male infertility were analyzed. Concentration of lead, cadmium and mercury were measured in blood and seminal plasma and whole blood using anodic stripping voltammetry and atomic absorption spectrophotometry. Serum samples were analyzed for follicle-stimulating hormone, luteinizing hormone and testosterone. Semen analyses were performed according to World Health Organization criteria. Mann-Whitney test and Spearman's rank correlations were used for unadjusted analyses. Multiple linear regression models were performed controlling for age, body mass index and number of cigarettes per day.</p> <p>Results</p> <p>There were no significant differences between cases and controls in the concentrations of heavy metals in any of the three body fluids. In multivariate analyses using all subjects no significant associations were found between serum hormone levels and metal concentrations. However there was a significant positive association between the percentage of immotile sperms and seminal plasma levels of lead and cadmium.</p> <p>Conclusions</p> <p>Our results suggest that the presence of lead and cadmium in the reproductive tract of men may be related to a moderate alteration of their seminal parameters.</p

Production, chemical characterization, and sensory profile of a novel spirit elaborated from spent coffee ground

This study describes a process for the production of a spirit from spent coffee ground (SCG), the chemical composition, and sensory profile of this distillate. The process consisted in three steps starting with the extraction of aroma compounds by hydrothermal treatment of SCG, followed by the fermentation of this extract supplemented with sucrose to ethanol, and the fermented broth distillation. Seventeen volatile compounds were identified in the distillate (including alcohols, esters, aldehydes, and acids), all of them in concentrations able to promote pleasant characteristics to the product. Based on the chemical composition, \SCG\ spirit was considered as having organoleptic quality acceptable for human consumption. Twelve descriptors defined the sensory characteristics of this product, including clarity and brilliance (visual analysis), coffee, roasted, alcohol, elegance and frankly (olfactory analysis), bitter, astringent and pungent (gustatory analysis), and finesse (olfactory and gustatory analyses). Coffee was the most representative aroma by olfactory analysis. Based on the sensory analysis, \SCG\ spirit was considered as having features of a pleasant beverage, with smell and taste of coffee