Stenosis triggers spread of helical Pseudomonas biofilms in cylindrical flow systems

Biofilms are multicellular bacterial structures that adhere to surfaces and often endow the bacterial population with tolerance to antibiotics and other environmental insults. Biofilms frequently colonize the tubing of medical devices through mechanisms that are poorly understood. Here we studied the helicoidal spread of Pseudomonas putida biofilms through cylindrical conduits of varied diameters in slow laminar flow regimes. Numerical simulations of such flows reveal vortical motion at stenoses and junctions, which enhances bacterial adhesion and fosters formation of filamentous structures. Formation of long, downstream-flowing bacterial threads that stem from narrowings and connections was detected experimentally, as predicted by our model. Accumulation of bacterial biomass makes the resulting filaments undergo a helical instability. These incipient helices then coarsened until constrained by the tubing walls, and spread along the whole tube length without obstructing the flow. A three-dimensional discrete filament model supports this coarsening mechanism and yields simulations of helix dynamics in accordance with our experimental observations. These findings describe an unanticipated mechanism for bacterial spreading in tubing networks which might be involved in some hospital-acquired infections and bacterial contamination of catheters.

Spread of Phlebotominae in temperate climates: province of Córdoba, Argentina

We report the presence of the competent vector for Leishmania spp, Migonemyia migonei, and the Evandromyia cortelezzii-sallesi complex south of its known distribution in the central temperate region of Argentina, in the province of Córdoba. The persistence of this phlebotomine in the northern border of the province, its association with a case of cutaneous leishmaniasis, and the new record in the outskirts of the city of Córdoba, the second most populated in the country, strengthens the need for regular vector surveillance and a case detection-sensitive health system in vulnerable regions, even in temperate climates.

Diseño de estratégias de comercialización para la penetración y posicionamiento de los productos de leche de soya, chocolate criollo, salsa inglesa, picante y soya de la empresa Samaritana S.A. de C.V. en los supermercados del municipio de San Salvador.

Actualmente la empresa Samaritana, S.A. de C.V. cuenta con una amplia gama de productos alimenticios que se distribuyen en supermercados y tiendas del país, sin embargo sus productos Leche de soya, Salsas Inglesa, Soya y Picante no están posicionados en mercado y Chocolate en tablilla aún no ha sido introducido. A raíz de lo expuesto anteriormente, se consideró de mucha importancia realizar una investigación que determinara la situación actual de la empresa en estudio. Cuyo objetivo principal es proporcionar una herramienta que oriente a la gerencia en la aplicación de estrategias necesarias para la penetración y posicionamiento de los productos. Para lo anterior se recopiló la información necesaria mediante cuestionarios dirigidos a los consumidores y gerentes de supermercados del Municipio de San Salvador y una entrevista dirigida la Gerente General de Samaritana, S.A. de C.V. Para los efectos de este estudio el tipo de investigación fue el descriptivo, ya que se buscó describir y especificar los elementos, propiedades o característica importantes de los clientes, la competencia, intermediarios, factores internos y externos que afectan a la empresa, para poder describir situaciones y eventos que se presentan en el mercado. Una vez recopilados los datos se tabularon y analizaron con el propósito de elaborar un diagnóstico específico sobre la situación actual de la empresa en mención. Con base al dicho diagnóstico se formularon las conclusiones con sus respectivas recomendaciones; de las cuales se pueden mencionar la más importante: La empresa no cuenta con un plan de comercialización que le permita posicionar y penetrar sus productos en el mercado actual. Los factores que mayormente influyen en la decisión de compra de los consumidores son la calidad y el precio. Los consumidores no conocen la marca Mana en ninguno de los productos en mención. Según la investigación realizada los consumidores no han escuchado el eslogan “Sabor, caído del cielo” Finalmente se desarrolló la propuesta del diseño de un plan estratégico de comercialización con el objetivo de contribuir al posicionamiento de los productos Leche de Soya, Salsas inglesa, Soya y Picante y a la penetración del Chocolate en tablilla; considerando para ello el establecimiento de estrategias de producto, precios, plaza y promoción. Y también la creatividad e innovación en el desarrollo de dicho plan.

The contribution of Angola to the early spread of the HIV-1 epidemic

Poster presented at the 22nd International HIV Dynamics and Evolution. Budapest, Hungary, 13-16 May 2015

Is there a need for “healthy” chocolate? Systematic literature review

Antecedentes: El chocolate tiene propiedades especiales que ayudan a proteger el cuerpo humano de enfermedades cardiovasculares, incrementa el colesterol HDL y reduce la presión sanguínea. El consumo de chocolate también ayuda a reducir el estrés, eleva el ´animo y reduce el cansancio. El propósito de esta revisión es identificar, seleccionar, organizar y resumir estudios que investiguen el chocolate en relación con la salud, las características sensoriales y las actitudes de las personas. Este artículo es parte de la tesis de maestría: Is there a need for “healthy” chocolate? Systematic literature review and consumer research in Belgium and in Denmark (Es necesario el chocolate “saludable”? Revisión sistemática de la literatura y estudio al consumidor en Bélgica y Dinamarca), presentada por la autora en Junio del 2015 a la Universidad de Aalborg en Copenhague. Métodos: Este estudio presenta tres áreas relacionadas con el chocolate: Chocolate y su relación con la salud; características sensoriales y aceptación del chocolate; y actitudes hacia el chocolate. Una revisión sistemática de la literatura fue realizada para identificar, seleccionar, organizar y resumir estudios que investiguen al chocolate en relación con estas tres áreas. Cuatro bases de datos fueron escogidas: PubMed, Science Direct, Scopus y Web of Science por sus extensiones y porque superponen investigaciones interdisciplinarias.Resultados: Se obtuvieron un total de 2062 hits en las cuatro bases de datos. Un total de sesenta artículos cumplieron los criterios y fueron identificados como relevantes. Los artículos fueron clasificados de acuerdo a las tres áreas incluidas en el estudio. En relación a la salud, se ha indicado en muchos estudios que los polifenoles en el chocolate pueden mejorar la salud, especialmente en enfermedades cardiovasculares. De acuerdo a las características sensoriales y aceptación del chocolate, se ha dicho que la forma del chocolate tiene una influencia en la percepción del mismo. Los polifenoles causan astringencia y amargor al chocolate, haciéndolo no muy apetecido para los consumidores; sin embargo, por razones de salud, los polifenoles deben ser conservados. Acerca de las actitudes hacia el chocolate, hay muchos factores que llevan al deseo incontrolable de consumir chocolate. El chocolate es el alimento más apetecido en Norte América, éste influencia el estado anímico y crea una sensación de saciedad. Conclusión: Con base en esta revisión se puede concluir que un chocolate “saludable” puede ser parte de una dieta saludable, a la gente le gusta disfrutar del chocolate, mujeres más que hombres. La literatura respalda las propiedades saludables que tiene el consumo del chocolate, por esto es necesario trabajar en el desarrollo de productos de chocolate.

Elaboración de confitería a base de chocolate con edulcorantes no calóricos

En este trabajo de titulación se detallan los aspectos más relevantes relacionados a la investigación, formulación y elaboración de uno de los placeres más agradables en la vida cotidiana de cualquier persona como lo es el chocolate. Cada uno de los chocolates realizados tiene como particularidad el estar endulzado con edulcorantes no calóricos como: stevia, sucralosa y jarabe de yacón, disminuyendo así el contenido de calorías presentes en los mismos. Entre los tres chocolates elaborados, la mejor formulación fue seleccionada mediante una prueba de cata resultando ganador el chocolate endulzado con jarabe de yacón, debido a que posee las mejores características sensoriales resaltando principalmente el dulzor y el sabor. Para comprobar que la mejor formulación cumple con los estándares de calidad de las normas INEN de chocolates se realizó un análisis físico-químico y se corroboraron estos resultados con un laboratorio certificado por parte del Servicio de Acreditación Ecuatoriano (SAE). Los resultados obtenidos determinaron que el porcentaje de grasa es menor a los chocolates existentes en el mercado. Además se realizaron pruebas de dureza para analizar las propiedades de textura presentes en el chocolate. Destacando que el chocolate endulzado con jarabe de yacón puede ser consumido por personas diabéticas y no diabéticas, al no tener en su formulación sacarosa como endulzante principal.

Una casa ideal : vivienda de chocolate

Fondo Margaritainés Restrepo

Determinantes del spread financiero del sector cooperativo de ahorro y crédito ecuatoriano

Esta investigación analiza los determinantes del spread financiero del sector cooperativo de ahorro y crédito ecuatoriano. La base teórica corresponde al modelo expuesto por Ho y Saunders (1981). Se construyeron variables micro y macroeconómicas para recoger los efectos que estas tienen sobre el margen de intermediación financiera. Se empleó un panel de datos mensuales para el periodo 2007-2014. Las estimaciones fueron realizadas mediante la metodología de errores estándar corregidos para datos de panel. Los resultados explican que el spread financiero del sector cooperativo depende particularmente de los niveles de morosidad, la eficiencia en sus gastos operacionales y el grado de endeudamiento público externo de la economía. Además, la concentración de mercado, los niveles de liquidez y la incertidumbre en los mercados internacionales inciden levemente en la determinación del spread.

Epidemiology and Emergence of Schmallenberg Virus Part 2: Pathogenesis and Risk of Viral Spread

Schmallenberg virus (SBV) is a novel Orthobunyavirus causing mild clinical signs in cows and malformations in aborted and neonatal ruminants in Europe. SBV belongs to the family Bunyaviridae and is transmitted by biting midges. This new virus was identified for the first time in blood samples of cows in the city of Schmallenberg in North-Rhine Westphalia in November 2011. Since then, the virus spread to several European countries. Here, we describe the pathogenesis and the risk of viral spread in the Portuguese territory.

Overlapped Sequence Types (sts) And Serogroups Of Avian Pathogenic (apec) And Human Extra-intestinal Pathogenic (expec) Escherichia Coli Isolated In Brazil.

Avian pathogenic Escherichia coli (APEC) strains belong to a category that is associated with colibacillosis, a serious illness in the poultry industry worldwide. Additionally, some APEC groups have recently been described as potential zoonotic agents. In this work, we compared APEC strains with extraintestinal pathogenic E. coli (ExPEC) strains isolated from clinical cases of humans with extra-intestinal diseases such as urinary tract infections (UTI) and bacteremia. PCR results showed that genes usually found in the ColV plasmid (tsh, iucA, iss, and hlyF) were associated with APEC strains while fyuA, irp-2, fepC sitDchrom, fimH, crl, csgA, afa, iha, sat, hlyA, hra, cnf1, kpsMTII, clpVSakai and malX were associated with human ExPEC. Both categories shared nine serogroups (O2, O6, O7, O8, O11, O19, O25, O73 and O153) and seven sequence types (ST10, ST88, ST93, ST117, ST131, ST155, ST359, ST648 and ST1011). Interestingly, ST95, which is associated with the zoonotic potential of APEC and is spread in avian E. coli of North America and Europe, was not detected among 76 APEC strains. When the strains were clustered based on the presence of virulence genes, most ExPEC strains (71.7%) were contained in one cluster while most APEC strains (63.2%) segregated to another. In general, the strains showed distinct genetic and fingerprint patterns, but avian and human strains of ST359, or ST23 clonal complex (CC), presented more than 70% of similarity by PFGE. The results demonstrate that some zoonotic-related STs (ST117, ST131, ST10CC, ST23CC) are present in Brazil. Also, the presence of moderate fingerprint similarities between ST359 E. coli of avian and human origin indicates that strains of this ST are candidates for having zoonotic potential.

Assessment Of Robustness On Analysis Using Headspace Solid-phase Microextraction And Comprehensive Two-dimensional Gas Chromatography Through Experimental Designs.

Plackett-Burman experimental design was applied for the robustness assessment of GC×GC-qMS (Comprehensive Two-Dimensional Gas Chromatography with Fast Quadrupolar Mass Spectrometric Detection) in quantitative and qualitative analysis of volatiles compounds from chocolate samples isolated by headspace solid-phase microextraction (HS-SPME). The influence of small changes around the nominal level of six factors deemed as important on peak areas (carrier gas flow rate, modulation period, temperature of ionic source, MS photomultiplier power, injector temperature and interface temperature) and of four factors considered as potentially influential on spectral quality (minimum and maximum limits of the scanned mass ranges, ions source temperature and photomultiplier power). The analytes selected for the study were 2,3,5-trimethylpyrazine, 2-octanone, octanal, 2-pentyl-furan, 2,3,5,6-tetramethylpyrazine, and 2-nonanone e nonanal. The factors pointed out as important on the robustness of the system were photomultiplier power for quantitative analysis and lower limit of mass scanning range for qualitative analysis.

Histologic Correlation Of Expression Of Ki-67 In Squamous Cell Carcinoma Of The Glottis According To The Degree Of Cell Differentiation.

Squamous cell carcinoma is the most common neoplasm of the larynx and glottis, and its prognosis depends on the size of the lesion, level of local invasion, cervical lymphatic spread, and presence of distant metastases. Ki-67 (MKI67) is a protein present in the core, whose function is related to cell proliferation. To evaluate the expression of marker Ki-67 in squamous cell carcinoma of the larynx and glottis and its correlation to pathological findings. Experimental study with immunohistochemistry analysis of Ki-67, calculating the percentage of the cell proliferation index in glottic squamous cell carcinomas. Sixteen cases were analyzed, with six well-differentiated and 10 poorly/moderately differentiated tumors. There was a correlation between cell proliferation index and degree of cell differentiation, with higher proliferation in poorly/moderately differentiated tumors. The cell proliferation index, as measured by Ki-67, may be useful in the characterization of histological degree in glottic squamous cell tumors.

High-resolution Transcript Profiling Of The Atypical Biotrophic Interaction Between Theobroma Cacao And The Fungal Pathogen Moniliophthora Perniciosa.

Witches' broom disease (WBD), caused by the hemibiotrophic fungus Moniliophthora perniciosa, is one of the most devastating diseases of Theobroma cacao, the chocolate tree. In contrast to other hemibiotrophic interactions, the WBD biotrophic stage lasts for months and is responsible for the most distinctive symptoms of the disease, which comprise drastic morphological changes in the infected shoots. Here, we used the dual RNA-seq approach to simultaneously assess the transcriptomes of cacao and M. perniciosa during their peculiar biotrophic interaction. Infection with M. perniciosa triggers massive metabolic reprogramming in the diseased tissues. Although apparently vigorous, the infected shoots are energetically expensive structures characterized by the induction of ineffective defense responses and by a clear carbon deprivation signature. Remarkably, the infection culminates in the establishment of a senescence process in the host, which signals the end of the WBD biotrophic stage. We analyzed the pathogen's transcriptome in unprecedented detail and thereby characterized the fungal nutritional and infection strategies during WBD and identified putative virulence effectors. Interestingly, M. perniciosa biotrophic mycelia develop as long-term parasites that orchestrate changes in plant metabolism to increase the availability of soluble nutrients before plant death. Collectively, our results provide unique insight into an intriguing tropical disease and advance our understanding of the development of (hemi)biotrophic plant-pathogen interactions.

The Role Of The Inflammatory Microenvironment In Thyroid Carcinogenesis.

Immune responses against thyroid carcinomas have long been demonstrated and associations between inflammatory microenvironment and thyroid carcinomas repeatedly reported. This scenario has prompted scientists throughout the world to unveil how the inflammatory microenvironment is established in thyroid tumors and what is its influence on the outcome of patients with thyroid carcinoma. Many studies have reported the role of evasion from the immune system in tumor progression and reinforced the weakness of the innate immune response toward thyroid cancer spread in advanced stages. Translational studies have provided evidence that an increased density of tumor-associated macrophages in poorly differentiated thyroid carcinoma (DTC) is associated with an aggressive phenotype at diagnosis and decreased cancer-related survival, whereas well-DTC microenvironment enriched with macrophages is correlated with improved disease-free survival. It is possible that these different results are related to different microenvironments. Several studies have provided evidence that patients whose tumors are not infiltrated by lymphocytes present a high recurrence rate, suggesting that the presence of lymphocytes in the tumor microenvironment may favor the prognosis of patients with thyroid carcinoma. However, the effect of lymphocytes and other immune cells on patient outcome seems to result from complex interactions between the tumor and immune system, and the molecular pattern of cytokines and chemokines helps to explain the involvement of the immune system in thyroid tumor progression. The inflammatory microenvironment may help to characterize aggressive tumors and to identify patients who would benefit from a more invasive approach, probably sparing the vast majority of patients with an indolent disease from unnecessary procedures.

Geographical Distribution Of The Association Between El Niño South Oscillation And Dengue Fever In The Americas: A Continental Analysis Using Geographical Information System-based Techniques.

El Niño South Oscillation (ENSO) is one climatic phenomenon related to the inter-annual variability of global meteorological patterns influencing sea surface temperature and rainfall variability. It influences human health indirectly through extreme temperature and moisture conditions that may accelerate the spread of some vector-borne viral diseases, like dengue fever (DF). This work examines the spatial distribution of association between ENSO and DF in the countries of the Americas during 1995-2004, which includes the 1997-1998 El Niño, one of the most important climatic events of 20(th) century. Data regarding the South Oscillation index (SOI), indicating El Niño-La Niña activity, were obtained from Australian Bureau of Meteorology. The annual DF incidence (AIy) by country was computed using Pan-American Health Association data. SOI and AIy values were standardised as deviations from the mean and plotted in bars-line graphics. The regression coefficient values between SOI and AIy (rSOI,AI) were calculated and spatially interpolated by an inverse distance weighted algorithm. The results indicate that among the five years registering high number of cases (1998, 2002, 2001, 2003 and 1997), four had El Niño activity. In the southern hemisphere, the annual spatial weighted mean centre of epidemics moved southward, from 6° 31' S in 1995 to 21° 12' S in 1999 and the rSOI,AI values were negative in Cuba, Belize, Guyana and Costa Rica, indicating a synchrony between higher DF incidence rates and a higher El Niño activity. The rSOI,AI map allows visualisation of a graded surface with higher values of ENSO-DF associations for Mexico, Central America, northern Caribbean islands and the extreme north-northwest of South America.