Emergencia del virus Chikungunya (chikv) en Chiapas, México: tendencias en patrones epidemiológicos e incriminación de vectores.

El virus chikungunya (CHIKV) es un arbovirus de la familia Togaviridae, género Alphavirus, transmitido principalmente por los mosquitos Aedes aegypti y Aedes albopictus. Esta enfermedad, que en un inicio emergió en Tanzania en 1952, se fue diseminando al resto del mundo hasta que en el año 2013 se reporta el primer caso de esta enfermedad en el continente americano, específicamente en la Isla de San Martín. Ante el avance progresivo hacia Centroamérica y Sudamérica, se mantuvo la alerta en la frontera sur de México ante la eventual entrada del virus a nuestro país. Por esta razón, se tuvo como objetivo estudiar la emergencia de CHIKV en el municipio fronterizo de Suchiate y la región del Soconusco del estado de Chiapas, para encontrar patrones epidemiológicos básicos durante la fase inicial del brote e incriminar qué vectores estuvieron transmitiendo este arbovirus. En el mes de octubre del 2014, se encuentra el primer brote causado por CHIKV en las localidades de Ciudad Hidalgo y el ejido “La Libertad”, donde se analizaron 65 pacientes, siendo positivos a CHIKV 59 (90.8%). Además, se realizaron muestreos de mosquitos en las mismas viviendas de la localidad de Ciudad Hidalgo en el mismo momento donde se muestrearon los casos positivos encontrándose una tasa de infección en Ae. aegypti de 32.26/1,000 mosquitos (IC 95% = 20.06–49.62). Después de comprobar el ingreso de CHIKV a nuestro país e incriminar al vector Ae. aegypti, se prosiguió a realizar un estudio observacional de corte en el hospital “Dr. Roberto Nettel”, en el cual se incluyeron 112 casos probables a fiebre chikungunya, con la finalidad de describir los principales síntomas observados y verificar si existe alguna alteración en los parámetros hemáticos y bioquímicos de los pacientes durante la infección. Luego de confirmar 95 casos (84.8%) los principales síntomas observados fueron fiebre, poliartralgias severas, exantema (rash), dolor de cabeza y nauseas. Adicionalmente, los parámetros de análisis de laboratorio arrojaron que los pacientes presentaron principalmente leucopenia, linfopenia, altos niveles de transaminasas, alta PCR y alta LDH. Este trabajo permitió generar más conocimiento epidemiológico acerca de esta enfermedad emergente que puede mejorar el diagnóstico clínico de ésta y conocer mejor su mecanismo de transmisión en nuestro país. ABSTRACT Chikungunya virus (CHIKV) is an arbovirus belonging to family Togaviridae, genus Alphavius, transmitted mainly by Aedes aegypti and Aedes albopictus mosquitoes. This disease emerged in Tanzania in 1952 and then disseminated worldwide until in 2013 the first case of CHIKV was reported in the American Continent, specifically in the Saint Martin Island. The progressive advance towards Central and South America has alarmed the Mexican south border before the eventual entrance of this arbovirus to our country. For this reason, the aim of this work was study the emergence of CHIKV in the border municipality of Suchiate and Soconusco Region from Chiapas State to find basic epidemiological patterns during the outbreak onset and incriminate the vectors involved during CHIKV transmission. In October 2014 the first CHIKV outbreak was identified in the localities of Ciudad Hidalgo and el ejido “La Libertad” where 65 patients were analyzed being positive 59 (90.8%). In addition, mosquito collections were performed in the same households during the outbreak in Ciudad Hidalgo. An infection rate of 32.26/1,000 mosquitoes (95% IC = 20.06–49.62) was found in Ae. aegypti populations from Ciudad Hidalgo. After proving CHIKV entrance to Mexico and incriminate Ae. aegypti as a CHIKV vector, an observational cross-sectional study was carried out in the hospital “Dr. Roberto Nettel” located in Tapachula which 112 probable cases of CHIKV were included. The aim was describing the main symptoms and verify if any clinical and/or biological feature was altered during CHIKV infection. A total of 95 cases (84.8%) were confirmed to CHIKV infection observing mainly the following symptoms: fever, polyartrhalgia, rash, headache and nausea. Furthermore, the biological features showed that patients exhibited leukopenia, lymphopenia, high levels of transaminases, PCR and LDH. This study contributed to epidemiological knowledge of chikungunya fever and may improve clinical diagnosis of this arboviral disease and know better the transmission mechanism in our country

Influencia de las condiciones de operación en la producción de hidrógeno por reformado de metanol: aproximación numérica

This work describes the unidimensional study of steam reforming of methanol at short pseudo-contact time. Steam reforming process (SRP) is important to hydrogen production as energetic vector. A compressible mathematical model 1-D is developed. Peppley kinetic mechanism (1999) is adopted. The numerical predictions show up the same trend as the experimental ones. A sensitivity analysis of the significant variables of the process is carried out (pressure, CH3OH/H2O ratio and temperature).Este trabajo describe el estudio unidimensional del proceso de reformado de metanol en cortos tiempos modificados de residencia. El proceso Reformado de metanol es importante para la producción de hidrógeno como vector energético. Un modelo matemático 1-D del reactor es desarrollado. Se adopta el mecanismo cinético de Peppley (1999). Las predicciones numéricas muestran la misma tendencia de los datos experimentales. Un análisis de sensibilidad de las variables significativas del proceso es realizado (presión, relación CH3OH/H2O y temperatura)

Influence of operating conditions in the hydrogen production by steam reforming of methanol: numerical approach

This work describes the unidimensional study of steam reforming of methanol at short pseudo-contact time. Steam reforming process (SRP) is important to hydrogen production as energetic vector. A compressible mathematical model 1-D is developed. Peppley kinetic mechanism (1999) is adopted. The numerical predictions show up the same trend as the experimental ones. A sensitivity analysis of the significant variables of the process is carried out (pressure, CH3OH/H2O ratio and temperature)

Simulação de um processo de purificação de biogás utilizando diferentes soluções de aminas

1 recurso en línea (páginas 51-60).The use of biogas generated in landfills has gained importance in developing countries like Colombia. Taking into account that this biogas presents poor combustion properties that make interchangeability with other combustible gases difficult, the elimination of gases and vapors, such as CO2 and H2O, through a cleaning process, in which the biogas is converted to biomethane, improves the biogas properties as a fuel gas for general use. In this work, we simulated the generation of biogas at El Carrasco sanitary landfill in Bucaramanga, using the US EPA (United States Environmental Protection Agency) landfill gas emissions model. Additionally, we simulated the biogas cleaning process to extract the remaining moisture using the ProMax software; for this, we used three different amines (MDEA, MEA, and DEA), followed by a glycol dehydration process. The results showed that the amine MEA produced the largest increase in the concentration of CH4 (90.37 %) for the biogas generated in the landfill. Furthermore, dehydration with glycol was an efficient process to obtain a gas with a high percentage of methane (91.47 %) and low water presence (1.27 %); this would allow the use of biomethane in conventional industrial combustion processes and power generation.La utilización del biogás producido en vertederos de basura ha ganado importancia en países en vía de desarrollo, como Colombia. Teniendo en cuenta que este biogás tiene propiedades pobres de combustión que dificultan el intercambio con otros combustibles, la eliminación de gases y vapores, como el CO2 y el H2O, por medio de procesos de purificación en los que el biogás es convertido a biometano, mejora las propiedades del biogás como combustible para uso general. En este trabajo se simuló la producción de biogás en el vertedero de basura El Carrasco (Bucaramanga), usando el modelo de emisiones de gases en vertederos de la US EPA (United States Environmental Protection Agency). Adicionalmente, se simuló el proceso de purificación del biogás utilizando el software ProMax; el objetivo de este proceso es extraer la humedad del biogás, para lo cual se utilizaron tres aminas diferentes (MDEA, MEA y DEA) y un proceso posterior de deshidratación con glicol. Los resultados mostraron que la purificación con amina MEA logró producir el mayor incremento en la concentración de CH4 (90.37 %) en el biogás generado en el vertedero. Además, la deshidratación con glicol fue un proceso eficiente para obtener gas con un alto porcentaje de metano (91.47 %) y un bajo porcentaje de agua (1.27 %); estos resultados sugieren que el biometano se podría usar en procesos industriales convencionales y en generación de energía.A utilização do biogás produzido em depósitos de lixo tem ganhado importância em países em via de desenvolvimento, como a Colômbia. Tendo em conta que este biogás tem propriedades pobres de combustão que dificultam o intercâmbio com outros combustíveis, a eliminação de gases e vapores, como o CO2 e o H2O, por meio de processos de purificação nos quais o biogás é convertido a biometano, melhora as propriedades do biogás como combustível para uso geral. Neste trabalho simulou-se a produção de biogás no depósito de lixo El Carrasco (Bucaramanga), usando o modelo de emissões de gases em depósitos da US EPA (United States Environmental Protection Agency). Adicionalmente, simulou-se o processo de purificação do biogás utilizando o software ProMax; o objetivo deste processo é extrair a humidade do biogás, para o qual utilizaram-se três aminas diferentes (MDEA, MEA e DEA) e um processo posterior de desidratação com glicol. Os resultados mostraram que a purificação com amina MEA logrou produzir o maior incremento na concentração de CH4 (90.37 %) no biogás gerado no depósito. Além disso, a desidratação com glicol foi um processo eficiente para obter gás com uma alta porcentagem de metano (91.47 %) e uma baixa porcentagem de água (1.27 %); estes resultados sugerem que o biometano poderia ser usado em processos industriais convencionais e em geração de energia.Bibliografía y webgrafía: páginas 59-60

Detection of aedes aegypti mosquitoes infected with dengue virus as a complementary method for increasing the sensitivity of surveillance: identification of serotypes 1, 2, and 4 by rt-pcr in Quintana Roo, Mexico

Abstract. Sensitivity of monitoring Aedes aegypti (L.) populations was determined to identify the distribution of dengue virus (DENV) during epidemics in Quintana Roo. From September to November 2012, we used a motorized aspirator to collect 2,144 female Ae. aegypti from 569 homes. These were grouped into 220 to use semi-nested RT-PCR for DENV, and positive groups were analyzed individually. Five groups (2.27%) were positive for DENV. Individual analysis yielded eight groups that tested positive, six with DENV-2, one DENV-1, and one DENV-4. The latter was not reported by the surveillance system that year. The mean number of female mosquitoes per household was 3.77 ± 5.71, and the rate of viral infection of Ae. aegypti was 0.4%. Most infected mosquitoes (49%) were concentrated in 10% of the houses. Monitoring Ae. aegypti infected with DENV has the potential to complement the current system of clinical and entomological surveillance

A case–control study of infections caused by Klebsiella pneumoniae producing New Delhi metallo-beta-lactamase-1: Predictors and outcomes

IntroductionInfections caused by antimicrobial-resistant bacteria are a significant cause of death worldwide, and carbapenemase-producing bacteria are the principal agents. New Delhi metallo-beta-lactamase-1 producing Klebsiella pneumoniae (KP-NDM-1) is an extensively drug-resistant bacterium that has been previously reported in Mexico. Our aim was to conduct a case–control study to describe the risk factors associated with nosocomial infections caused by K. pneumoniae producing NDM-1 in a tertiary-care hospital in Mexico.MethodsA retrospective case–control study with patients hospitalized from January 2012 to February 2018 at the Hospital Civil de Guadalajara “Fray Antonio Alcalde” was designed. During this period, 139 patients with a culture that was positive for K. pneumoniae NDM-1 (cases) and 486 patients hospitalized in the same department and on the same date as the cases (controls) were included. Data were analyzed using SPSS v. 24, and logistic regression analysis was conducted to calculate the risk factors for KP-NDM-1 infection.ResultsOne hundred and thirty-nine case patients with a KP-NDM-1 isolate and 486 control patients were analyzed. In the case group, acute renal failure was a significant comorbidity, hospitalization days were extended, and significantly more deaths occurred. In a multivariate analysis of risk factors, the independent variables included the previous use of antibiotics (odds ratio, OR = 12.252), the use of a urinary catheter (OR = 5.985), the use of a central venous catheter (OR = 5.518), the use of mechanical ventilation (OR = 3.459), and the length of intensive care unit (ICU) stay (OR = 2.334) as predictors of infection with NDM-1 K. pneumoniae.ConclusionIn this study, the previous use of antibiotics, the use of a urinary catheter, the use of a central venous catheter, the use of mechanical ventilation, and ICU stay were shown to be predictors of infection with NDM-1 K. pneumoniae and were independent risk factors for infection with NDM-1 K. pneumoniae

Field Effectiveness of Drones to Identify Potential Aedes aegypti Breeding Sites in Household Environments from Tapachula, a Dengue-Endemic City in Southern Mexico

Aedes aegypti control programs require more sensitive tools in order to survey domestic and peridomestic larval habitats for dengue and other arbovirus prevention areas. As a consequence of the COVID-19 pandemic, field technicians have faced a new occupational hazard during their work activities in dengue surveillance and control. Safer strategies to monitor larval populations, in addition to minimum householder contact, are undoubtedly urgently needed. Drones can be part of the solution in urban and rural areas that are dengue-endemic. Throughout this study, the proportion of larvae breeding sites found in the roofs and backyards of houses were assessed using drone images. Concurrently, the traditional ground field technician’s surveillance was utilized to sample the same house groups. The results were analyzed in order to compare the effectiveness of both field surveillance approaches. Aerial images of 216 houses from El Vergel village in Tapachula, Chiapas, Mexico, at a height of 30 m, were obtained using a drone. Each household was sampled indoors and outdoors by vector control personnel targeting all the containers that potentially served as Aedes aegypti breeding sites. The main results were that the drone could find 1 container per 2.8 found by ground surveillance; however, containers that were inaccessible by technicians in roofs and backyards, such as plastic buckets and tubs, disposable plastic containers and flowerpots were more often detected by drones than traditional ground surveillance. This new technological approach would undoubtedly improve the surveillance of Aedes aegypti in household environments, and better vector control activities would therefore be achieved in dengue-endemic countries

Revisiting the Crystal Structure of BaCe0.4Zr0.4Y0.2O3-δ Proton Conducting Perovskite and Its Correlation with Transport Properties

Oxides with proton conductivity have a great potential for applications in environmental energy technology. Despite the BaCe0.4Zr0.4Y0.2O3-δ (BCZY) perovskites being well-known proton conductors, it is a challenge to determine the optimal operating temperature range where the energy applications benefit most from this unique property. The protonic transport properties strongly depend on crystal structure and local distortions in the participating cation coordination sphere, according to related temperatures and gas feed. The transport and crystallographic properties of BCZY were simultaneously studied by impedance spectroscopy (IS) and synchrotron X-ray diffraction (S-XRD). A strong correlation between conductivity and the lattice parameter, corresponding in principle to a cubic symmetry, was observed, mainly between 400 and 700 °C. The protonic conductivity range was analyzed by the H/D isotopic effect on the impedance spectra, which helped to identify protonic conduction as the governing transport mechanism below 600 °C, while the transport via oxygen vacancies dominates above this temperature. In order to assess the real crystallographic structure, the simultaneous refinement of laboratory XRD and neutron diffraction (ND) patterns was performed. According to this, BCZY changes from rhombohedral symmetry below 400 °C to cubic at 600 °C in a second-order phase transition. Complementary quasielastic neutron scattering (QENS) enables us to determine a protonic jump length of 3.1 Å, which matches the O-O distances in the octahedral oxygen coordination sphere around the cations. These results support the protonic self-diffusion through proton hopping between intraoctahedral O sites as the main transport mechanism up to 600 °C.Fil: Basbus, Juan Felipe. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Arce, Mauricio Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Napolitano, Federico Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Troiani, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Alonso, José Antonio. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Saleta, Martin Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; Argentina. Centro Nacional de Pesquisa em Energia e Materiais; BrasilFil: González, Miguel A.. Institut Laue Langevin; FranciaFil: Cuello, Gabriel Julio. Institut Laue Langevin; FranciaFil: Fernández Díaz, María Teresa. Institut Laue Langevin; FranciaFil: Pardo Sainz, Miguel. Universidad de Zaragoza. Instituto de Ciencias de Materiales de Aragon; EspañaFil: Bonanos, Nikolaos. Technical University of Denmark; DinamarcaFil: Jimenez, Catalina Elena. Helmholtz-Zentrum; AlemaniaFil: Giebeler, Lars. No especifíca;Fil: Figueroa, Santiago J. A.. Centro Nacional de Pesquisa em Energia e Materiais; BrasilFil: Caneiro, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Serquis, Adriana Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Mogni, Liliana Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; Argentin

Anosmin-1 over-expression increases adult neurogenesis in the subventricular zone and neuroblast migration to the olfactory bulb

New subventricular zone (SVZ)-derived neuroblasts that migrate via the rostral migratory stream are continuously added to the olfactory bulb (OB) of the adult rodent brain. Anosmin-1 (A1) is an extracellular matrix protein that binds to FGF receptor 1 (FGFR1) to exert its biological effects. When mutated as in Kallmann syndrome patients, A1 is associated with severe OB morphogenesis defects leading to anosmia and hypogonadotropic hypogonadism. Here, we show that A1 over-expression in adult mice strongly increases proliferation in the SVZ, mainly with symmetrical divisions, and produces substantial morphological changes in the normal SVZ architecture, where we also report the presence of FGFR1 in almost all SVZ cells. Interestingly, for the first time we show FGFR1 expression in the basal body of primary cilia in neural progenitor cells. Additionally, we have found that A1 over-expression also enhances neuroblast motility, mainly through FGFR1 activity. Together, these changes lead to a selective increase in several GABAergic interneuron populations in different OB layers. These specific alterations in the OB would be sufficient to disrupt the normal processing of sensory information and consequently alter olfactory memory. In summary, this work shows that FGFR1-mediated A1 activity plays a crucial role in the continuous remodelling of the adult OB.This research was supported by grants from the Spanish Ministerio de Economía, Innovación y Competitividad MINECO (SAF2009-07842, ADE10-0010, RD07-0060-2007, RD12-0032-12 and SAF2012-40023 to FdC; and BFU2010-18284 to JMG-V), FISCAM (Gobierno de Castilla-La Mancha, Spain—Grant Number PI2007-66), the Junta de Castilla y León (Spain, to EW), and from the Fundación Eugenio Rodríguez Pascual (Spain) to FdC. DGG and VMB were PhD students hired by Gobierno de Castilla-La Mancha (MOV2010-JI/11 and MOV2007-JI/19, respectively). FdCS is a CSIC staff scientist in special permission hired by SESCAM (Gobierno de Castilla-La Mancha, Spain). PFE was a researcher hired by SESCAM (Gobierno de Castilla-La Mancha) and ADE10-0010.Peer reviewe

Chikungunya Virus as Cause of Febrile Illness Outbreak, Chiapas, Mexico, 2014

Since chikungunya virus (CHIKV) was introduced into the Americas in 2013, its geographic distribution has rapidly expanded. Of 119 serum samples collected in 2014 from febrile patients in southern Mexico, 79% were positive for CHIKV or IgM against CHIKV. Sequencing results confirmed CHIKV strains closely related to Caribbean isolates