Impacts of detritivore diversity loss on instream decomposition are greatest in the tropics.

The relationship between detritivore diversity and decomposition can provide information on how biogeochemical cycles are affected by ongoing rates of extinction, but such evidence has come mostly from local studies and microcosm experiments. We conducted a globally distributed experiment (38 streams across 23 countries in 6 continents) using standardised methods to test the hypothesis that detritivore diversity enhances litter decomposition in streams, to establish the role of other characteristics of detritivore assemblages (abundance, biomass and body size), and to determine how patterns vary across realms, biomes and climates. We observed a positive relationship between diversity and decomposition, strongest in tropical areas, and a key role of abundance and biomass at higher latitudes. Our results suggest that litter decomposition might be altered by detritivore extinctions, particularly in tropical areas, where detritivore diversity is already relatively low and some environmental stressors particularly prevalent.

Growth Hormone Modulation of Hepatic Epidermal Growth Factor Receptor Signaling.

Epidermal growth factor receptor (EGFR) signaling has a central role in the regenerative response of the liver upon injury and is involved in cellular transformation linked to chronic damage. Hepatic EGFR expression, trafficking, and signaling are regulated by growth hormone (GH). Chronically elevated GH levels are associated with liver cancer development and progression in mice. Studies in different in vivo experimental models indicate that EGF and GH mutually crossregulate in a complex manner. Several factors, such as the extent of exposure to supraphysiological GH levels and the pattern of GH administration, are important variables to be considered in exploring the interplay between the two hormones in connection with the progression of hepatic tumors.

Latitude dictates plant diversity effects on instream decomposition.

Running waters contribute substantially to global carbon fluxes through decomposition of terrestrial plant litter by aquatic microorganisms and detritivores. Diversity of this litter may influence instream decomposition globally in ways that are not yet understood. We investigated latitudinal differences in decomposition of litter mixtures of low and high functional diversity in 40 streams on 6 continents and spanning 113° of latitude. Despite important variability in our dataset, we found latitudinal differences in the effect of litter functional diversity on decomposition, which we explained as evolutionary adaptations of litter-consuming detritivores to resource availability. Specifically, a balanced diet effect appears to operate at lower latitudes versus a resource concentration effect at higher latitudes. The latitudinal pattern indicates that loss of plant functional diversity will have different consequences on carbon fluxes across the globe, with greater repercussions likely at low latitudes.

Residues and residue pairs of evolutionary importance differentially direct signaling bias of D2 dopamine receptors.

The D2 dopamine receptor and the serotonin 5-hydroxytryptamine 2A receptor (5-HT2A) are closely-related G-protein-coupled receptors (GPCRs) from the class A bioamine subfamily. Despite structural similarity, they respond to distinct ligands through distinct downstream pathways, whose dysregulation is linked to depression, bipolar disorder, addiction, and psychosis. They are important drug targets, and it is important to understand how their bias toward G-protein versus ß-arrestin signaling pathways is regulated. Previously, evolution-based computational approaches, difference Evolutionary Trace and Evolutionary Trace-Mutual information (ET-Mip), revealed residues and residue pairs that, when switched in the D2 receptor to the corresponding residues from 5-HT2A, altered ligand potency and G-protein activation efficiency. We have tested these residue swaps for their ability to trigger recruitment of ß-arrestin2 in response to dopamine or serotonin. The results reveal that the selected residues modulate agonist potency, maximal efficacy, and constitutive activity of ß-arrestin2 recruitment. Whereas dopamine potency for most variants was similar to that for WT and lower than for G-protein activation, potency in ß-arrestin2 recruitment for N124H3.42 was more than 5-fold higher. T205M5.54 displayed high constitutive activity, enhanced dopamine potency, and enhanced efficacy in ß-arrestin2 recruitment relative to WT, and L379F6.41 was virtually inactive. These striking differences from WT activity were largely reversed by a compensating mutation (T205M5.54/L379F6.41) at residues previously identified by ET-Mip as functionally coupled. The observation that the signs and relative magnitudes of the effects of mutations in several cases are at odds with their effects on G-protein activation suggests that they also modulate signaling bias.

A pilot study of safety of sulfamethoxazole, trimethoprim and guaifenesin in pediatric and adult patients with acute bronchitis.

OBJECTIVE: This exploratory study assessed the safety of the combination of sulfamethoxazole, trimethoprim and guaifenesin (STG) in adult and pediatric patients with acute bronchitis according to local labelling in Peru. RESULTS: We enrolled 51 pediatric and 52 adult participants diagnosed with acute bronchitis and indication of STG. The mean ages were 7.6 years (SD ± 3.2 years) and 42.8 years (SD ± 16.1) and the proportion of female patients were 51% and 65%, respectively. The duration of treatment in pediatric patients was < 5 days in 2% of patients, 5 days in 13.7%, 6-7 days, in 82.4% and > 7 days in 2% while in adults patients it was < 5 days in 17%, 5 days in 69.2%; 6-7 days in 28.8% of patients. Adverse events (AEs) were registered in 9.6% and 19.2% of pediatric and adult patients, respectively. These AEs had definite relation of causality with the study drugs in 2 adults (20% of AEs) and possible causality with the study drugs in 4 pediatric (80% of AEs) and 2 adult cases (20% of AEs). Our results provide valuable data to develop trials of pharmacovigilance where different statistical parameters should be considered to calculate an adequate sample size in studies evaluating STG in pediatric or adult patients. Trial registration NCT02879981 and NCT02902640.

Sinorhizobium fredii HH103 nolR and nodD2 mutants gain capacity for infection thread invasion of Lotus japonicus Gifu and Lotus burttii.

Sinorhizobium fredii HH103 RifR , a broad-host-range rhizobial strain, forms ineffective nodules with Lotus japonicus but induces nitrogen-fixing nodules in Lotus burttii roots that are infected by intercellular entry. Here we show that HH103 RifR nolR or nodD2 mutants gain the ability to induce infection thread formation and to form nitrogen-fixing nodules in L. japonicus Gifu. Microscopy studies showed that the mode of infection of L. burttii roots by the nodD2 and nolR mutants switched from intercellular entry to infection threads (ITs). In the presence of the isoflavone genistein, both mutants overproduced Nod-factors. Transcriptomic analyses showed that, in the presence of Lotus japonicus Gifu root exudates, genes related to Nod factors production were overexpressed in both mutants in comparison to HH103 RifR . Complementation of the nodD2 and nolR mutants provoked a decrease in Nod-factor production, the incapacity to form nitrogen-fixing nodules with L. japonicus Gifu and restored the intercellular way of infection in L. burttii. Thus, the capacity of S. fredii HH103 RifR nodD2 and nolR mutants to infect L. burttii and L. japonicus Gifu by ITs and fix nitrogen L. japonicus Gifu might be correlated with Nod-factor overproduction, although other bacterial symbiotic signals could also be involved.

Diseño de un programa de análisis de peligros y puntos críticos control (HACCP) para la producción de toxoide tetánico / Design of a program of hazard analysis and critical control point (HACCP) for production of Tetanus Toxoid

El toxoide tetánico es una neurotoxina modificada que induce la formación de una antitoxina protectora contra la enfermedad denominada tétanos. Este antígeno es obtenido a partir de procesos fermentativos con la bacteria anaerobia Clostridium tetani y es utilizado para la formulación de vacunas simples y combinadas inactivadas. Con el propósito de atender a las recomendaciones y regulaciones de la Organización Mundial de la Salud (OMS), el objetivo de este trabajo fue diseñar un Programa de Análisis de Peligros y Puntos Críticos de Control (HACCP) en la producción del antígeno Toxoide Tetánico, desde la recepción de la cepa certificada en el área de producción hasta el almacenamiento del toxoide tetánico purificado. Para ello, inicialmente se evaluó el cumplimiento de los prerequisitos (BPM, POES, BPL). Posteriormente, se procedió al diseño del plan HACCP mediante la ejecución de las 5 tareas preliminares y la aplicación de los 7 principios, conforme a la metodología descrita por la OMS. A partir del análisis de peligros en todas las etapas del proceso de producción del toxoide tetánico se identificaron 3 puntos críticos de control: detoxificación, filtración estéril final y almacenamiento de toxoide tetánico purificado. Se establecieron los límites críticos, los procedimientos de vigilancia, las acciones correctivas, los procedimientos de verificación y de documentación. La propuesta tiene como fin garantizar la calidad e inocuidad del producto elaborado, la protección del personal involucrado en el proceso y del medio ambiente con miras a la obtención de la certificación como laboratorio productor de vacunas

Tetanus toxoid is a modified neurotoxin that induces the formation of protective antitoxin of the disease called tetanus. This antigen is obtained from fermentation processes with anaerobic bacteria Clostridium tetani and it is used to formulate simple and combined inactivated vaccines. In order to meet the recommendations and regulations of World Health Organization (WHO), the aim of this work was to design a Program of Hazard Analysis and Critical Control Points (HACCP) in the production of antigen Tetanus Toxoid, starting from the receipt of the certified strain in the production area through the storage of purified tetanus toxoid. For this, initially fulfilling the prerequisites (GMP, SSOP and GLP) was evaluated. Subsequently, we proceeded to design HACCP plan by running 5 preliminary tasks and application of the 7 principles, according to the methodology described by WHO. From the hazard analysis at all stages of the production process of tetanus toxoid three critical control points were identified: detoxification, final sterile filtration and storage of purified tetanus toxoid. Critical limits, monitoring procedures, corrective actions, verification and documentation procedures were established. The proposal aims to assure the quality and safety of the final product, the protection of personnel involved in the process and the environment, with a view to obtaining certification as a vaccine production laboratory

Effect of Ki-67 assessment in the distribution of breast cancer subtypes: Evaluation in a cohort of Latin American patients.

Breast cancer (BC) is a heterogeneous disease composed of four main subtypes with distinct clinical and epidemiological features. Although several reports have described the distribution of BC subtypes in Latin America, the majority of them have not included the cellular marker, Ki-67, in the immunohistochemical (IHC) panel. The aim of the present study was to describe the distribution of BC subtypes in a cohort of Latin American women using an IHC panel with Ki-67. A prospective cohort of 580 patients in three centers of Peru (the Hospital Nacional Edgardo Rebagliatti Martins, the Hospital Nacional Guillermo Almenara Irigoyen, the Hospital Nacional Alberto Sabogal, Lima) and one in Uruguay (Instituto Nacional del Cáncer, Montevideo) were evaluated. BC phenotypes were classified according to an IHC panel: Estrogen receptor (ER), progesterone receptor (PgR), HER2 and Ki-67. Silver in situ hybridization was used when the HER2 status, as determined by IHC, was equivocal. The associations between the BC phenotypes and their clinicopathological features were evaluated. ER was positive in 65% of the cases (n=377), and PgR in 50% (n=203). In total, 79.1% (n=459) were HER2-negative, 19.8% (n=115) were HER2-positive and 1% (n=6) had an equivocal status. With respect to Ki-67, 44.7% of the patients exhibited staining in >14% of the tumor cells (n=259). The distribution of subtypes was as follows: Luminal A, 31.9% (n=183); luminal B, 35% (n=201); HER2, 12.1% (n=70); and triple-negative, 20.9% (n=120). When Ki-67 was not included in the panel, the frequency of luminal A was 41.1% and luminal B, 25.8% (9.2% of the cases were misclassified). Ki-67 was most highly expressed in triple-negative and HER2 tumors. Inclusion of Ki-67 in the IHC panel to assign subtypes revealed a higher frequency of luminal B tumors than was reported previously for Latin American women with BC, whereas the distribution of triple-negative and HER2 tumors were similar to that previously reported. In conclusion, these results demonstrated that excluding Ki-67 from the panel of IHC markers may lead to an underestimation of the rates of luminal B tumors.

La biopelícula: una nueva concepción de la placa dentobacteriana / Biofilm: a new conception of dentobacterial plaque

La presente revisión se realizó con el objetivo de actualizar las concepciones de la placa dentobacteriana, que debe ser comprendida como una biopelícula. Se detallaron, en su formación, etapas del ciclo vital, sistema de comunicación entre microrganismos, intercambio génico, composición microbiana y resistencia a los mecanismos de defensa del huésped y a losantibióticos. Esta nueva visión de la placa microbiana posee una gran importancia en el diagnóstico de las enfermedades periodontales, pues permite caracterizar su agente causal e interpretarlo como una comunidad de especies diversas, pero estas constituyen una unidad ecológica compleja, con una gran potencialidad, capaz de desencadenar una respuesta inflamatoria mucho más potente y destructiva que cuando las especies que la integran se encuentran en forma planctónica ibre flotación(AU)

Estado periodontal y su posible relación con variables funcionales de laoclusión / Periodontal state and its possible relationship to functional occlusal variables

Entre noviembre del 2010 y septiembre del 2011 se realizó un estudio descriptivo transversal paracaracterizar la posible relación del factor oclusal con el estado periodontal de pacientes atendidos en el servicio de Periodoncia de la Clínica Estomatológica Victoria de Santa Clara. Constituyeron unidades de análisis 40 pacientes y 1 112 dientes. Se determinó el estado periodontal al aplicar losíndices periodontal de Russell y de movilidad de Miller, la medición de la profundidad de las bolsas periodontales y la presencia o no de pérdidas óseas. Se estudiaron variables oclusales funcionales seleccionadas. No se obtuvo correlación entre la profundidad de las bolsas y las alteraciones funcionales oclusales, excepto en el contacto exagerado. Las pérdidas angulares presentaron mayor profundidad de bolsas. La distribución de los dientes afectados en su función oclusal, según los códigos del índice periodontal, no siguió una tendencia única. La mayoría de los dientes conalteraciones funcionales presentaron movilidad dentaria(AU)

La osteoporosis y su influencia en el estado periodontal de mujeres postmenopáusicas / Osteoporosis and its influence on periodontal status of postmenopausal women

Se realizó un estudio analítico transversal sobre la osteoporosis y su influencia en el estado periodontal de mujeres postmenopáusicas, la muestra estuvo integrada por 50 mujeres postmenopáusicas divididas en dos grupos: 20 con osteoporosis (grupo 1) y 30 sin la enfermedad (grupo 2). Las variables estudiadas fueron la edad, el tipo de menopausia, el tiempo de postmenopausia, el grado de osteoporosis y la severidad y la extensión de la pérdida de inserción clínica periodontal basada en el índice de Carlos. Los datos fueron procesados a través del paquete estadístico SPSS versión 11; se aplicaron pruebas estadísticas como la de Chi cuadrado, la U de Mann-Whitney, la de Fisher y la de Kruskal-Wallis. Todas las mujeres con osteoporosis presentaron pérdida de inserción clínica periodontal de forma generalizada; en el grupo de las mujeres que no padecían osteoporosis solo una pequeña parte presentó pérdida de inserción clínica periodontal. Existió una relación directamente proporcional entre el grado de osteoporosis y la pérdida de inserción clínica periodontal; no ocurrió así con el tiempo de postmenopausia. Predominó la menopausia natural, la edad de 58 años y más y el tiempo de postmenopausia de cinco a 13 años(AU)

GH/STAT5 signaling during the growth period in livers of mice overexpressing GH.

GH/STAT5 signaling is desensitized in the liver in adult transgenic mice overexpressing GH; however, these animals present greater body size. To assess whether the STAT5 pathway is active during the growth period in the liver in these animals, and how signaling modulators participate in this process, growing transgenic mice and normal siblings were evaluated. STAT5 does not respond to an acute GH-stimulus, but displays higher basal phosphorylation in the livers of growing GH-overexpressing mice. GH receptor and the positive modulators glucocorticoid receptor and HNF1 display greater abundance in transgenic animals, supporting the activity of STAT5. The negative modulators cytokine-induced suppressor and PTP1B are increased in GH-overexpressing mice. The suppressors SOCS2 and SOCS3 exhibit higher mRNA levels in transgenic mice but lower protein content, indicating that they are being actively degraded. Therefore, STAT5 signaling is increased in the liver in GH-transgenic mice during the growth period, with a balance between positive and negative effectors resulting in accelerated but controlled growth.

GH administration patterns differently regulate epidermal growth factor signaling.

Current GH administration protocols imply frequent s.c. injections, resulting in suboptimal compliance. Therefore, there is interest in developing delivery systems for sustained release of the hormone. However, GH has different actions depending on its continuous or pulsatile plasma concentration pattern. GH levels and circulating concentration patterns could be involved in the regulation of epidermal growth factor receptor (EGFR) expression in liver. Aberrant expression of this receptor and/or its hyperactivation has been associated with the pathogenesis of different types of carcinoma. Considering that one of the adverse effects associated with GH overexpression and chronic use of GH is the increased incidence of malignancies, the aim of this study was to analyze the effects of GH plasma concentration patterns on EGFR expression and signaling in livers of mice. For this purpose, GH was administered by s.c. daily injections to produce an intermittent plasma pattern or by osmotic pumps to provoke a continuously elevated GH concentration. Intermittent injections of GH induced upregulation of liver EGFR content, augmented the response to EGF, and the induction of proteins involved in promotion of cell proliferation in female mice. In contrast, continuous GH delivery in male mice was associated with diminished EGFR in liver and decreased EGF-induced signaling and expression of early genes. The results indicate that sustained delivery systems that allow continuous GH plasma patterns would be beneficial in terms of treatment safety with regard to the actions of GH on EGFR signaling and its promitogenic activity.

El empleo del autoexamen bucal como actividad educativa en estudiantes de Estomatología / The use of oral self-examination as an educational activity in Dentistry students

Fundamento: la prevención del cáncer bucal es un tema de obligatorio conocimiento para los estudiantes de Estomatología. Objetivo: identificar el nivel de preparación de los estudiantes de Estomatología sobre la realización del autoexamen bucal como actividad educativa en la comunidad.Métodos: se realizó una investigación descriptiva con enfoque cualitativo, en la Facultad de Estomatología de la Universidad de Ciencias Médicas de Villa Clara, durante el curso escolar 2013-2014, se trabajó con una población de 179 alumnos de quinto año de la carrera. Los métodos teóricos empleados fueron el analítico-sintético, el inductivo-deductivo, el histórico-lógico. Entre los empíricos: el análisis de documentos (Plan de estudio C y D de la carrera de Estomatología) y la encuesta en forma de cuestionario, dirigida a los estudiantes. Resultados: se constató que los contenidos referentes al autoexamen bucal se limitan al primer año de la carrera y posteriormente no se integran en otras asignaturas. Los estudiantes no utilizan con la frecuencia requerida este procedimiento como actividad educativa, sin embargo, la mayoría conoce cómo hacerlo. Conclusiones: los resultados obtenidos sobre la labor educativa mediante la enseñanza del autoexamen bucal para la prevención de este tipo de cáncer, reclaman de una reflexión por parte de profesores y directivos sobre el manejo y control de esta actividad, como parte del accionar diario de los futuros estomatólogos en el desempeño de la labor de promoción de salud y prevención de enfermedades en la comunidad(AU)

Hepatocellular alterations and dysregulation of oncogenic pathways in the liver of transgenic mice overexpressing growth hormone.

Growth hormone (GH) overexpression throughout life in transgenic mice is associated with the development of liver tumors at old ages. The preneoplastic pathology observed in the liver of young adult GH-overexpressing mice is similar to that present in humans at high risk of hepatic cancer. To elucidate the molecular pathogenesis underlying the pro-oncogenic liver pathology induced by prolonged exposure to elevated GH levels, the activation and expression of several components of signal transduction pathways that have been implicated in hepatocellular carcinogenesis were evaluated in the liver of young adult GH-transgenic mice. In addition, males and females were analyzed in parallel in order to evaluate sexual dimorphism. Transgenic mice from both sexes exhibited hepatocyte hypertrophy with enlarged nuclear size and exacerbated hepatocellular proliferation, which were higher in males. Dysregulation of several oncogenic pathways was observed in the liver of GH-overexpressing transgenic mice. Many signaling mediators and effectors were upregulated in transgenic mice compared with normal controls, including Akt2, NFκB, GSK3ß, ß-catenin, cyclin D1, cyclin E, c-myc, c-jun and c-fos. The molecular alterations described did not exhibit sexual dimorphism in transgenic mice except for higher gene expression and nuclear localization of cyclin D1 in males. We conclude that prolonged exposure to GH induces in the liver alterations in signaling pathways involved in cell growth, proliferation and survival that resemble those found in many human tumors.

Validación de un modelo para la formación del estomatólogo general básico en promoción de salud / Validation of a model for the formation of the basic general stomatologist in health promotion

Se realizó una investigación enmarcada dentro de la metodología para la evaluación curricular, con predominio de los métodos cualitativos, en la Facultad de Estomatología de la Universidad de Ciencias Médicas de Villa Clara, en el curso escolar 2007-2008, con el objetivo de validar un modelo teórico metodológico para la formación del estomatólogo general básico en promoción de salud. Para su desarrollo se aplicaron métodos de nivel teórico y empírico, y el modelo se valida mediante su puesta en práctica a través de un estudio de casos múltiples de tipo transversal. Este estudio demuestra la posibilidad de implementar el modelo y la necesidad de incorporar elementos esenciales que permiten su mejor comprensión y aplicación ulterior(AU)

Language Shift in the United States and Foreign-Born Older Mexican Heritage Individuals: Co-ethnic Context for Language Resistance.

In this study, we investigate individual-level language shift in a population of Mexican origin Latinos/as aged 65 and up. By using data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly, we investigate their English language use as the dependent variable in a hierarchical linear model. The microlevel independent continuous variable is their level of contact with "Anglos"; the macrolevel continuous independent variable is the percentage of Mexicans in tract of residence. After accounting for their generational status, other microlevel social and health covariates, and tract-level attributes, we found a direct relationship between contact with Anglos and a "shift" toward more English language use, where as co-ethnic concentration increases, the influence of contact with Anglos decreases. We frame this article with a discussion on language shifting, and explain how co-ethnic concentration may provide the resources for engaging in a language resistance.

Signal molecules in the peanut-bradyrhizobia interaction.

Main nodulation signal molecules in the peanut-bradyrhizobia interaction were examined. Flavonoids exuded by Arachis hypogaea L. cultivar Tegua were genistein, daidzein and chrysin, the latest being released in lower quantities. Thin layer chromatography analysis from genistein-induced bacterial cultures of three peanut bradyrhizobia resulted in an identical Nod factor pattern, suggesting low variability in genes involved in the synthesis of these molecules. Structural study of Nod factor by mass spectrometry and NMR analysis revealed that it shares a variety of substituents with the broad-host-range Rhizobium sp. NGR234 and Bradyrhizobium spp. Nodulation assays in legumes nodulated by these rhizobia demonstrated differences between them and the three peanut bradyrhizobia. The three isolates were classified as Bradyrhizobium sp. Their fixation gene nifD and the common nodulation genes nodD and nodA were also analyzed.