Characterization of the Adherence of Clostridium difficile Spores: The Integrity of the Outermost Layer Affects Adherence Properties of Spores of the Epidemic Strain R20291 to Components of the Intestinal Mucosa

Indexación: Web of Science.Clostridium difficile is the causative agent of the most frequently reported nosocomial diarrhea worldwide. The high incidence of recurrent infection is the main clinical challenge of C. difficile infections (CBI). Formation of C. difficile spores of the epidemic strain R20291 has been shown to be essential for recurrent infection and transmission of the disease in a mouse model. However, the underlying mechanisms of how these spores persist in the colonic environment remains unclear. In this work, we characterized the adherence properties of epidemic R20291 spores to components of the intestinal mucosa, and we assessed the role of the exosporium integrity in the adherence properties by using cdeC mutant spores with a defective exosporium layer. Our results showed that spores and vegetative cells of the epidemic R20291 strain adhered at high levels to monolayers of Caco-2 cells and mucin. Transmission electron micrographs of Caco-2 cells demonstrated that the hair-like projections on the surface of R20291 spores are in close proximity with the plasma membrane and microvilli of undifferentiated and differentiated monolayers of Caco-2 cells. Competitive-binding assay in differentiated Caco-2 cells suggests that spore-adherence is mediated by specific binding sites. By using spores of a cdeC mutant we demonstrated that the integrity of the exosporium layer determines the affinity of adherence of C. difficile spores to Caco-2 cells and mucin. Binding of fibronectin and vitronectin to the spore surface was concentration-dependent, and depending on the concentration, spore-adherence to Caco-2 cells was enhanced. In the presence of an aberrantly-assembled exosporium (cdeC spores), binding of fibronectin, but not vitronectin, was increased. Notably, independent of the exosporium integrity, only a fraction of the spores had fibronectin and vitronectin molecules binding to their surface. Collectively, these results demonstrate that the integrity of the exosporium layer of strain R20291 contributes to selective spore adherence to components of the intestinal mucosa.http://journal.frontiersin.org/article/10.3389/fcimb.2016.00099/ful

LA MIOSTATINA: REGULADOR DEL CRECIMIENTO MUSCULAR Y ALTERNATIVA PARA LA SALUD

La miostatina (MSTN) también conocida como la GDF8, es un regulador negativo del crecimiento del musculo esquelético y responsable del correcto desarrollo de la masa muscular.  Su expresión está determinada por muchos mecanismo específicos, por ejemplo dominio  de proteínas específicas y genes relacionados. A su vez también, también se obtuvo información acerca de su influencia en determinadas enfermedades que aquejan a nivel de los tejidos musculares como por ejemplo sarcopenia y también relacionándose con el gen FTO (gen de la obesidad). La revisión de la literatura d acerca de la expresión de esta proteína deja en claro que el buen manejo de esta mediante el uso de la Ingeniería Genética, podría ayudar aliviar estos males que debilitan de forma progresiva el sistema esquelético, debilitando el movimiento de las personas.   DOI: https://doi.org/10.25176/RFMH.v17.n2.84

A prediction model based on data mining to forecast the expectations of passing from a college student

The present work has as objective to apply data mining techniques to develop a predictive model to forecast the chance of passing that will have a college student at the time of enrolling in a particular subject. Given that the academic record of the student can be known, and based on that information, we propose an Artificial Neural Network (ANN) that allows, using various configurations, to predict and assess our goal. The model has been applied to a compulsory subject of higher education of a University and given the results obtained. This model can be applied to any other subject analogous with satisfactory results

Impacto de las Abejas (Apis mellifera L.) Como Agentes Polinizadores en el Rendimiento del Cultivo de Zucchini (Cucurbita pepo L.) en el Canton Riobamba, Provincia de Chimborazo

The impact of bees (Apis mellifera L.) as pollinators in the yield of the zucchini (Cucurbita pepo L.) crop in the Riobamba canton, Chimborazo province, was evaluated using a Randomized Complete Block Design (RCBD). This was done using three treatments and three repetitions. The treatments evaluated were: the zucchini cultivation inside the micro tunnel covered with entomological mesh with the presence of bees, the zucchini cultivation inside the micro tunnel covered with anti aphids mesh without the presence of bees, and the open field zucchini cultivation. The evaluated parameters were number of days to the appearance of the fruits, percentage of fertilized and unfertilized flowers, number of fruits per plant, size of fruits, diameter of fruits, weight of fruit, and yield in kg / ha per treatment. The best results achieved in most parametersthat were evaluated such as the percentage of flowering, number of fruits per plant, size of fruit in cm, diameter of fruit in cm, weight of the fruit in grams, yield in kg/ha by treatment, and economic analysis were obtained with the presence of bees (Apis mellifera L.) as pollinating agents in the tunnel. This is in addition to meshes during the flowering stage of the zucchini crop, with an average yield of 14.9 tn/ha.Se evaluó el impacto de las abejas (Apis mellifera L.) como agentes polinizadores en el rendimiento del cultivo de zucchini (Cucurbita pepo L.) en el cantòn Riobamba, provincia de Chimborazo. Para llevar a cabo esta evaluación se utilizó un diseño de bloques completos a azar (DBCA), con tres tratamientos y tres repeticiones. Los tratamientos evaluados fueron: El cultivo de zucchini dentro del micro túnel cubierto con malla entomológica con presencia de abejas, el cultivo de zucchini dentro del micro túnel cubierto con malla antiáfidossin presencia de abejas y el cultivo de zucchini a campo abierto. Los parámetros evaluados fueron número de días transcurridos después de la aparición de los frutos, porcentaje de flores fecundadas y no fecundadas, número de frutos por planta, tamaño de frutos, diámetro de frutos, peso del fruto y rendimiento en kg/ha por tratamiento. Los mejores resultados alcanzados en la mayoría de los parámetros evaluados como el porcentaje de floración, número de frutos por planta, tamaño de fruto en (cm), diámetro de fruto en (cm), peso del fruto en gramos, rendimiento en kg/ha por tratamiento y análisis económico, se obtuvieron con la presencia de las abejas (Apis mellifera L.) como agentes polinizadores en el túnel con mallas durante la etapa de floración del cultivo de zucchini, con un rendimiento en promedio de 14.9 tn/ha

COPD: can genetic Background inform about disease heterogeneity?

People with COPD vary substantially on their pulmonary (e.g., airway obstruction) and extra-pulmonary (e.g., symptoms, functional status) manifestations. The aim of this study was to relate this high heterogeneity to the patient’s genetic Background, namely focusing on polymorphisms associated with COPD and COPD-associated phenotypes and features. Summary statistics for COPD and COPD-associated phenotypes and features (emphysema, FEV1, FEV1/FVC, smoking, BMI, asthma, airway responsiveness, coronary heart disease, blood pressure, pulmonary artery enlargement, resting heart rate and resting oxygen saturation) were obtained from GWAS Catalog (https://www.ebi.ac.uk/gwas/ accessed in August 2021). A local COPD cohort was genotyped using Global Screening Arrays (GSA-Illumina) and polygenic risk scores were calculated per phenotype/feature. A cluster analysis was then carried out to determine how patients would group according to their assessed genetic risks. The study currently includes 255 participants with COPD (68 [61, 74] years old; 79.61% male; FEV1/FVC 53.02 [41.24, 61.94]). Our preliminary results show that people cluster into 3 main groups based on their genetic risk for emphysema, followed by COPD, whilst their clinical characteristics remained similar among groups. Future work is currently being conducted to further explore these clusters and perform their validation. This work was funded by FEDER funds through COMPETE 2020, Operational Programme for Competitiveness and Internationalization (POCI-01-0145-FEDER-028806), CENTRO 2020 (CENTRO-01-0246-FEDER-000018; CENTRO-08-5864-FSE-000039) and by Fundação para a Ciência e a Tecnologia (UI/BD/151337/2021). The iBiMED is supported by FCT funds under UIDP/04501/2020.publishe

Heart rate and cardiovascular responses to commercial flights: relationships with physical fitness

The aim of this study was to examine the influence of physical fitness on cardiac autonomic control in passengers prior to, during and following commercial flights. Twenty-two, physically active men (36.4 +/- 6.4 years) undertook assessments of physical fitness followed by recordings of 24-h heart rate (HR), heart rate variability (HRV), and blood pressure (BP) on a Control (no flight) and Experimental (flight) day. Recordings were analyzed using a two-way analysis of variance for repeated measures with relationships between variables examined via Pearson product moment correlation coefficients. Compared to the Control day, 24-h HR was significantly greater (>7%) and HRV measures (5-39%) significantly lower on the Experimental day. During the 1-h flight, HR (24%), and BP (6%) were increased while measures of HRV (26-45%) were reduced. Absolute values of HRV during the Experimental day and relative changes in HRV measures (Control-Experimental) were significantly correlated with measures of aerobic fitness (r = 0.43 to 0.51;-0.53 to -0.52) and body composition (r = -0.63 to -0.43; 0.48-0.61). The current results demonstrated that short-term commercial flying significantly altered cardiovascular function including the reduction of parasympathetic modulations. Further, greater physical fitness and lower body fat composition were associated with greater cardiac autonomic control for passengers during flights. Enhanced physical fitness and leaner body composition may enable passengers to cope better with the cardiovascular stress and high allostatic load associated with air travel for enhanced passenger well-being

Production Response and Digestive Enzymatic Activity of the Pacific White Shrimp Litopenaeus vannamei (Boone, 1931) Intensively Pregrown in Microbial Heterotrophic and Autotrophic-Based Systems

Shrimp postlarvae were reared into different microcosm systems without water exchange; a traditional system based on simple fertilization to improve microalgae concentration (control), an autotrophic system (AS) based on the promotion of biofloc and biofilm by the addition of fertilizer and artificial substrates and a heterotrophic system (HS) based on the promotion of heterotrophic bacteria by the addition of nitrogenous and carbonaceous sources and artificial substrates. Better growth performance and survival were registered in shrimp from the AS and HS compared to the control. Feed conversion ratios were below 0.7 for all treatments, but AS and HS were significantly lower than the control. Regarding digestive performance, no significant differences were observed for trypsin, amylase and lipase activities among AS and control shrimp; however, shrimp from HS showed a higher trypsin and amylase activities, suggesting a higher digestive activity caused by the presence of microbial bioflocs. The presence of biofilm and bioflocs composed by either autotrophic or heterotrophic organisms in combination with formulated feed improved the growth performance and survival of shrimp. Apparently, such combination fits the nutritional requirements of shrimp

Upstream dam impacts on gilded catfish Brachyplatystoma rousseauxii (Siluriformes: Pimelodidae) in the Bolivian Amazon

This paper explores the effects of two run-of-river dams (Jirau and Santo Antônio) built in cascade in the middle Madeira River (Brazil) on the interruption of long-distance migration routes of the gilded catfish (Brachyplatystoma rousseauxii). A participative monitoring system was set up to compare capture by commercial fishers approximately 1500 km upstream ofthe dams in Bolivia, before (1998-2007) and after (2015-2017) dam closure. A significant decrease in gilded catfish catches and in catch per unit effort was observed after dam closure, whereas no significant difference in mean weight was found. Back-estimation of age suggests that the few individuals remaining after dam closure in 2009 are a mixture of old homers that returned upstream before dam closure, and residents hatched after dam closure and trapped in the upper Madeira. Unless fishways in the Madeira River dams improve their efficiency, the gilded catfish might become rare and in danger of regional extinction in the upper Madeira basin in the next few years, negatively affecting river fisheries.Fil: Van Damme, Paul A.. Instituto de Investigación Aplicada de Recursos Acuáticos; Bolivia. Universidad Mayor de San Simón; BoliviaFil: Córdova Clavijo, Leslie. Instituto de Investigación Aplicada de Recursos Acuáticos; BoliviaFil: Baigún, Claudio Rafael M.. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Hauser, Marilia. Universidade Federal de Rondônia; Brasil. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; FranciaFil: da Costa Doria, Carolina R.. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; Francia. Universidade Federal de Rondônia; BrasilFil: Duponchelle, Fabrice. Universidade Federal de Rondônia; Brasi

Composición bromatológica de la carne de conejos suplementados con mataratón y cachaza de palma aceitera

RESUMENObjetivo. Evaluar comparativamente el efecto de la suplementación del alimento balanceado comercial (ABC) con follaje de mataratón (Gliricidia sepium) y cachaza de palma aceitera (Elaeis guineensis) en la composición bromatológica de la carne de conejo. Materiales y métodos. Las muestras de carne estudiadas en el presente trabajo, provienen de una investigación previa con un diseño experimental de bloques al azar con tres tratamientos (dietas) y tres repeticiones (bloques) con muestreo de tres réplicas por repetición, donde se utilizaron 27 conejos machos mestizos durante el período postdestete divididos en tres tratamientos: uno control (T0), alimentados sólo con ABC, y dos suplementados con mataratón y cachaza de palma aceitera en proporciones de 30 y 10% (T1), y 10 y 30% (T2), respectivamente, a manera de comparar el efecto de las dietas en el valor nutricional. Resultados. Las muestras de carne provenientes de los diferentes animales en tratamiento, se evaluaron encontrando que la suplementación no afectó significativamente la composición bromatológica (p>0.05) para el contenido de humedad (70.77 a 72.42%), proteínas (19.08 a 20.34%), cenizas (1.53 a 1.68%) y lípidos (6.48 a 7.23%); indicando que indistintamente de la dieta empleada, suplementando el ABC con mataratón/fibra de palma o no, las carnes de conejo obtenidas son nutricionalmente idénticas como alimento. Conclusiones. Con base en los resultados, se sugiere que el follaje de mataratón y la fibra de palma aceitera podrían constituir una alternativa como recursos agronómicos tropicales en la producción de carne de conejo para el consumo human

Vitamin B12 levels in thyroid disorders: A systematic review and meta-analysis

Background and aims: Numerous studies have found an association between vitamin deficiency and thyroid disorders (TD). The presence of anti-parietal cell antibodies is indicative of reduced ability to absorb vitamin B12. Thus, this study reviewed the existing studies with the objective of assessing differences in the serum levels of vitamin B12 among patients with and without TD, the frequency of vitamin B12 deficiency in patients with TD, and the presence of anti-parietal cell antibodies in patients with TD. Methods: A meta-analysis of random-effects model was conducted to calculate pooled frequencies, mean differences (MD), and their respective 95% confidence intervals (CI). We identified 64 studies that met our inclusion criteria (n = 28597). Results: We found that patients with hypothyroidism had lower vitamin B12 levels than healthy participants (MD: −60.67 pg/mL; 95% CI: −107.31 to −14.03 pg/mL; p = 0.01). No significant differences in vitamin B12 levels were observed between healthy participants and patients with hyperthyroidism (p = 0.78), autoimmune thyroid disease (AITD) (p = 0.22), or subclinical hypothyroidism (SH) (p = 0.79). The frequencies of vitamin B12 deficiency among patients with hypothyroidism, hyperthyroidism, SH, and AITD were 27%, 6%, 27%, and 18%, respectively. Conclusions: Patients with hypothyroidism had lower levels of vitamin B12 than healthy participants. No significant differences were observed between vitamin B12 levels and hyperthyroidism, AITD, or SH. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=324422, identifier (CRD42022324422)