Regulation of spermatogenesis by small non-coding RNAs: Role of the germ granule

The spermatogenic process relays in highly regulated gene expression mechanisms at the transcriptional and post-transcriptional levels to generate the male gamete that is needed for the perpetuation of the species. Small non-coding RNA pathways have been determined to participate in the post-transcriptional regulatory processes of germ cells. The most important sncRNA molecules that are critically involved in spermatogenesis belong to the miRNA and piRNAs pathways as illustrated by animal models where ablation of specific protein components displays male infertility. Several elements of these regulatory pathways have been found in the nuage or germ granule, a non-membranous cytoplasmatic structure that can be seen in spermatocytes and spermatids. This notion suggests that germ granules may act as organizer centers for silencing pathways in the germline. In general, miRNAs regulate spermatogenesis through targeting and down-regulation of specific transcripts to eventually promote sperm development. However, piRNAs are powerful repressors of transposon elements expression in the spermatogenic process. Here we describe the suggested functions that miRNA and piRNAs pathways execute in the regulation of spermatogenesis and include some recent studies in the field. Despite major strides on the detailed molecular mechanisms of sncRNAs in relation to spermatogenesis, there is plenty to discover on this fascinating regulatory program

La figura del voluntariado en Fundación Down Zaragoza

En su mayoría las instituciones sociales cuentan con un grupo de voluntarios, los cuales participan en las diferentes actividades. Son múltiples las motivaciones, expectativas, entre otros aspectos que les han llevado a participar de forma activa en un determinado organismo. Es muy importante cuidar a dichos individuos ya que su acción altruista es imprescindible para el funcionamiento de los centros. En este estudio se pone la atención en el ámbito de la discapacidad y más concretamente en la Fundación Down Zaragoza, la cual tiene como objetivo contribuir en la calidad de vida de las personas con discapacidad intelectual y de sus familias, es decir dar una respuesta integral, mediante la atención directa, investigaciones, estudios, entre otros. Cabe destacar que en dicha institución se utilizan una serie de estrategias para que ambas partes, tanto el centro como los propios voluntarios, tengan un objetivo final común y es la integración social de los usuarios de la fundación

Prevalence of malnutrition in a group of institutionalized psychogeriatric patients using different diagnostic criteria

Producción CientíficaMalnutrition (MN) is a highly prevalent condition in the elderly. It is associated with functional impairment, disability, frailty, and sarcopenia. The aim was to analyze the capacity of GLIM and ESPEN criteria to diagnose MN in a sample of institutionalized psychogeriatric patients. Clinical and anthropometric data were collected in a cross-sectional study. Patients’ frailty, dependence, functional capacity, MNA, hand-grip strength (HS), and sarcopenia were evaluated. Body composition (BC) was estimated by conventional bioimpedance analysis. MN diagnosis was established using the ESPEN and the GLIM criteria based on fat-free mass index (GLIM-FFMI), appendicular skeletal muscle mass index (GLIM-ASMMI), skeletal muscle mass index (GLIM-SMMI), and HS (mGLIM). Ninety-two patients (57.6% men; mean age: 79.4 years) were studied. Depending on the diagnosis criteria, MN prevalence was between 25% (ESPEN) and 41.3% (GLIM-SMMI). Agreement between ESPEN and all GLIM criteria was poor, but it was excellent between all GLIM criteria (kappa > 0.8). Phenotypic criteria carried more weight in the diagnosis of MN than etiological ones. Depending on the parameter used, the prevalence of reduced muscle mass was notably different. Differences in BMI, BC, inflammation, and albumin are detected by the GLIM-FFMI criteria in the MN and non-MN subjects. Also, this criterion is the only one that identified differences in phase angle (PhA) between these groups. In the elderly, PhA can be very useful to monitor nutritional status

Bioimpedance vector analysis and conventional bioimpedance to assess body composition in elderly adults with dementia

Rationale Although dementia and nutritional status have been shown to be strongly associated, differences in body composition (BC) among elderly with dementia have not yet to be firmly established. Objective To assess the BC through conventional and vector bioimpedance analysis (BIA and BIVA, respectively) in a sample of institutionalized elderly men with and without dementia, in order to detect dementia-related BC changes. Methods Forty-one institutionalized men aged 65 years or older (23 without dementia- CG- and 18 with dementia-DG-) were measured with BIA and interpreted with BIVA and predictive equations. Results Age (74.4 and 75.7 y) and BMI (22.5 and 23.6 kg/m2) were similar for DG and CG, respectively. Resistance and resistance/height ratio did not differ significantly between groups Reactance and reactance/height ratio were 21.2 and 20.4% lower in DG than in CG. Phase angle was significantly lower in DG (mean: 4.0; 95% CI: 3.6-4.3 degrees) than in CG (mean: 4.7; 95% CI: 4.3-5.1 degrees). Mean fat mass index (6.0 and 7.0 kg/m2), and mean fat-free mass index (16.4 and 16.6 kg/m2) were similar in DG and CG. BIVA showed a significant downward migration of the ellipse in DG with respect to CG (T2=15.1, p<0.01). Conclusion Conventional BIA showed no significant differences in BC between DG and CG, even though reactance and reactance/height were about 21% lower in DG. Nevertheless, a body cell mass depletion and an increase in the extracellular/intracellular water-ratio were identified in DG using BIVA. BIVA reflects dementia-related changes in BC better than BIA.Peer ReviewedPreprin

Efecto de la realimentación en la composición corporal de mujeres con anorexia nerviosa restrictiva; antropometría frente a impedancia bioeléctrica

Objetivo: Evaluar la composición corporal en un grupo de pacientes desnutridas con anorexia nerviosa, respecto de controles sanas, antes y después del soporte nutricional, mediante antropometría y bioimpedancia. Métodos: Estudio observacional prospectivo. Se realizó una antropometría completa y un análisis de bioimpedancia a 12 mujeres con anorexia nerviosa restrictiva (24,5 años) al ingreso hospitalario y semanalmente durante la realimentación. El grupo control estuvo formado por 24 mujeres sanas (21 años). Se aplicaron los test t-Student, U-Mann-Whitney, t-Student para medidas repetidas o Wilcoxon. La concordancia entre antropometría y BIA se analizó mediante el coeficiente de correlación intraclase y Bland-Altman. Resultados: Las pacientes mejoraron significativamente todos los índices de composición corporal a lo largo de la estancia hospitalaria, aunque sus valores al alta siguieron siendo menores que los de las controles. La media de peso ganado fue 5,22 kg (DE: 1,42), de los que el 51,4% fueron masa grasa, con distribución central preferentemente. En las controles la ecuación de BIA que mejor concuerda con antropometría es la de Sun (CCI = 0,896); en las pacientes la concordancia fue más débil, al ingreso y al alta. Conclusiones: La realimentación produce una ganancia ponderal, fundamentalmente a expensas de masa grasa, con distribución central; no se consigue restablecer el estado nutricional. La concordancia entre antropometría y bioimpedancia para el estudio de la composición corporal es aceptable, especialmente en sujetos sanos. Se recomienda emplear antropometría, si no se dispone de BIA vectorial o algún método gold estandard para el análisis de la composición corporal, en casos de alteraciones importantes en la composición corporal y/o el balance hídrico

Specific bioelectrical impedance vector analysis (BIVA) is more accurate than classic BIVA to detect changes in body composition and in nutritional status in institutionalised elderly with dementia

A new analytical variation of bioelectrical impedance vector analysis (BIVA), called specific BIVA, has shown to be more accurate in detecting changes in fat mass than classic BIVA.To compare classic and specific BIVA in order to identify which is more strongly associated with psycho-functional and nutritional indicators in a group of institutionalised elderly patients with dementia.Cross-sectional study. Fifty-four patients (34 women, 20 men) with dementia in moderately severe to very severe stages and aged 60–95years underwent geriatric nutritional assessment, including body mass index calculations, the Mini Nutritional Assessment, the Geriatric Nutritional Risk Index, and whole body composition analysis.With specific BIVA (unlike with classic BIVA), significant differences were found between women with moderately severe and very severe dementia. In the BIVA conducted for body mass index, the confidence ellipses produced with the classic BIVA approach were highly overlapping; but with specific BIVA, significant differences were observed between the women in different nutritional categories (malnutrition, risk of malnutrition, normal weight and obesity). On the other hand, both approaches distinguished malnourished women from those who were at risk of malnutrition, according to the Mini Nutritional Assessment; and men with a moderate-high risk of malnutrition from men with no risk, on the basis of the Geriatric Nutritional Risk Index.Overall, the findings of the present study suggest that specific BIVA is more effective than classic BIVA in identifying bioelectrical changes associated with psycho-functional and nutritional indicators in institutionalised elderly with dementia

Bioimpedance vector analysis and conventional bioimpedance to assess body composition in older adults with dementia

Producción CientíficaAlthough dementia and nutritional status have been shown to be strongly associated, differences in body composition (BC) among older people with dementia have not yet been firmly established. The aim of this study was to assess BC through conventional and vector bioimpedance analysis (BIA and BIVA, respectively) in a sample of institutionalized older men with and without dementia, in order to detect dementia-related BC changes.Forty-one institutionalized men ages ≥65 y (23 without dementia [CG] and 18 with dementia [DG]) were measured with BIA and interpreted with BIVA and predictive equations.Age (74.4 and 75.7 y) and body mass index (22.5 and 23.6 kg/m 2 ) were similar for DG and CG, respectively. Resistance and ratio of resistance to height did not differ significantly between the two groups. Reactance and ratio of reactance to height were 21.2% and 20.4% lower in DG than in CG. Phase angle was significantly lower in DG (mean = 4.0; 95% confidence interval [CI], 3.6°–4.3°) than in CG (mean = 4.7; 95% CI, 4.3°–5.1°). Mean fat mass index (6 and 7 kg/m 2 ), and mean fat-free mass index (16.4 and 16.6 kg/m 2 ) were similar in both groups. BIVA showed a significant downward migration of the ellipse in DG with respect to CG (T 2 = 15.1; P < 0.01).Conventional BIA showed no significant differences in BC between DG and CG, although reactance and ratio of reactance to height were about 21% lower in DG. Nevertheless, a body cell mass depletion and an increase in the ratio of extracellular to intracellular water were identified in DG using BIVA. BIVA reflects dementia-related changes in BC better than BI

Presencia de malnutrición y riesgo de malnutrición en ancianos institucionalizados con demencia en función del tipo y estadío evolutivo

Producción CientíficaDeterminar si existen diferencias en el estado nutricional de los pacientes con demencia en función del tipo y la severidad de la misma. Método: Mediante un estudio transversal se realizó una valoración del estado nutricional (valoración antropométrica, Mini Nutricional Assessment, protocolo de Chang) en 83 ancianos institucionalizados con diagnóstico de demencia en estadíos evolutivos 5, 6 y 7 de las escalas GDS (Global Deterioration Scale) y FAST (Functional Assessment Stating). Los resultados se analizaron mediante los tests Chi-cuadrado, ANOVA o Kruskal-Wallis, contrastes a posteriori de Scheffé y test de tendencia lineal. La significación se alcanzó con p < 0,05. Resultados: La edad media de los residentes fue de 81,22 años. El IMC reveló que el 21% de la muestra presentaba riesgo de malnutrición y el 14,5% malnutrición por defecto. En cambio, el MNA clasificó al 56,6% de los residentes en situación de riesgo de malnutrición y al 41% con malnutrición. Según el método de Chang el porcentaje de pacientes malnutridos ascendió al 75,9%. Ninguna de estas variables mostró asociación con el tipo de demencia. Se observó una asociación significativa entre el estadío evolutivo de la demencia y el IMC (p = 0,004), MNA (p = 0,002 y p = 0,006 para la puntuación y la categoría, respectivamente), circunferencia muscular del brazo (p = 0,043) y circunferencia de la pantorrilla (p = 0,043); aunque no para el porcentaje de masa grasa ni para el diagnóstico nutricional establecido por el método de Chang (grado y tipo de MN). El test de tendencia lineal confirmó que tanto las puntuaciones del MNA y del IMC, como los valores de la circunferencia muscular del brazo y de la circunferencia de la pantorrilla fueron menores en los estadíos de demencia más severos. Conclusión: Independientemente del tipo de demencia, la presencia de malnutrición en ancianos institucionalizados aumenta conforme lo hace el estadío evolutivo de la misma

A point-of-care device for sensitive protein quantification

In this paper we present the design of a new point-of-care device for protein quantification. The proposed design is based on a novel aptamer-mediated methodology and real time polymerase chain reaction (RT-PCR), a robust and ultrasensitive method for DNA amplification, which we employ for very sensitive quantification of proteins. In addition, we have also developed an algorithm for the processing of raw fluorescence data from the portable RT-PCR device. The algorithm leads to better linearity than a proprietary software from a commercially available RT-PCR machine. The modular nature of the system allows for easy assembly and adjustment towards a variety of biomarkers for applications in disease diagnosis and personalised medicine

Aptasensor for quantification of leptin through PCR amplification of short DNA-aptamers

Protein quantification is traditionally performed through enzyme-linked immunosorbent assay (ELISA), which involves long preparation times. To overcome this, new approaches use aptamers as an alternative to antibodies. In this paper, we present a new approach to quantify proteins with short DNA aptamers through polymerase chain reaction (PCR) resulting in shorter protocol times with comparatively improved limits of detection. The proposed method includes a novel way to quantify both the target protein and the corresponding short DNA-aptamers simultaneously, which also allows us to fully characterize the performance of aptasensors. Human leptin is used as a target protein to validate this technique, because it is considered an important biomarker for obesity-related studies. In our experiments, we achieved the lowest limit of detection of 100 pg/mL within less than 2 h, a limit affected by the dissociation constant of the leptin aptamer, which could be improved by selecting a more specific aptamer. Because of the simple and inexpensive approach, this technique can be employed for Lab-On-Chip implementations and for rapid “on-site” quantification of proteins