43 research outputs found
Insights into the genome and proteome of <i>Sphingomonas paucimobilis</i> strain 20006FA involved in the regulation of polycyclic aromatic hydrocarbon degradation
In order to study the mechanisms regulating the phenanthrene degradation pathway and the intermediate-metabolite accumulation in strain S. paucimobilis 20006FA, we sequenced the genome and compared the genome-based predictions to experimental proteomic analyses. Physiological studies indicated that the degradation involved the salicylate and protocatechuate pathways, reaching 56.3% after 15 days. Furthermore, the strain degraded other polycyclic aromatic hydrocarbons (PAH) such as anthracene (13.1%), dibenzothiophene (76.3%), and fluoranthene. The intermediate metabolite 1-hydroxy2-naphthoic acid (HNA) accumulated during phenanthrene catabolism and inhibited both bacterial growth and phenanthrene degradation, but exogenous-HNA addition did not affect further degradation. Genomic analysis predicted 126 putative genes encoding enzymes for all the steps of phenanthrene degradation, which loci could also participate in the metabolism of other PAH. Proteomic analysis identified enzymes involved in 19 of the 23 steps needed for the transformation of phenanthrene to trichloroacetic-acid intermediates that were upregulated in phenanthrene cultures relative to the levels in glucose cultures.
Moreover, the protein-induction pattern was temporal, varying between 24 and 96 h during phenanthrene degradation, with most catabolic proteins being overexpressed at 96 h—e. g., the biphenyl dioxygenase and a multispecies (2Fe–2S)-binding protein. These results provided the first clues about regulation of expression of phenanthrene degradative enzymes in strain 20006FA and enabled an elucidation of the metabolic pathway utilized by the bacterium. To our knowledge the present work represents the first investigation of genomic, proteomic, and physiological studies of a PAH-degrading Sphingomonas strain.Centro de Investigación y Desarrollo en Fermentaciones Industriale
Insights into the genome and proteome of <i>Sphingomonas paucimobilis</i> strain 20006FA involved in the regulation of polycyclic aromatic hydrocarbon degradation
In order to study the mechanisms regulating the phenanthrene degradation pathway and the intermediate-metabolite accumulation in strain S. paucimobilis 20006FA, we sequenced the genome and compared the genome-based predictions to experimental proteomic analyses. Physiological studies indicated that the degradation involved the salicylate and protocatechuate pathways, reaching 56.3% after 15 days. Furthermore, the strain degraded other polycyclic aromatic hydrocarbons (PAH) such as anthracene (13.1%), dibenzothiophene (76.3%), and fluoranthene. The intermediate metabolite 1-hydroxy2-naphthoic acid (HNA) accumulated during phenanthrene catabolism and inhibited both bacterial growth and phenanthrene degradation, but exogenous-HNA addition did not affect further degradation. Genomic analysis predicted 126 putative genes encoding enzymes for all the steps of phenanthrene degradation, which loci could also participate in the metabolism of other PAH. Proteomic analysis identified enzymes involved in 19 of the 23 steps needed for the transformation of phenanthrene to trichloroacetic-acid intermediates that were upregulated in phenanthrene cultures relative to the levels in glucose cultures.
Moreover, the protein-induction pattern was temporal, varying between 24 and 96 h during phenanthrene degradation, with most catabolic proteins being overexpressed at 96 h—e. g., the biphenyl dioxygenase and a multispecies (2Fe–2S)-binding protein. These results provided the first clues about regulation of expression of phenanthrene degradative enzymes in strain 20006FA and enabled an elucidation of the metabolic pathway utilized by the bacterium. To our knowledge the present work represents the first investigation of genomic, proteomic, and physiological studies of a PAH-degrading Sphingomonas strain.Centro de Investigación y Desarrollo en Fermentaciones Industriale
Presencia de enfermedades en majadas caprinas de las quebradas áridas de Jujuy y Salta
Una encuesta transversal ad hoc se llevó a cabo en 40 unidades productoras familiares (UPF) de las áridas en las provincias de Jujuy y Salta, con el objetivo de describir la presencia de enfermedades en sus majadas caprinas. Se recabaron datos del manejo general y sanitario en particular. Se procesaron sueros para el diagnóstico de brucelosis por las pruebas tamiz del antígeno bufferado en placa (BPA) y confirmadas por polarización fluorecente (FPA), para paratuberculosis (PTBC), artritis-encefalitis (CAEV), chlamydiosis, herpesvirus caprino tipo 1 (CaHV-1), fiebre Q y toxoplasmosis se utilizó ELISA indirecto y para leptospirosis microaglutinación. Se determinaron los valores de Cu2+, Zn2+, Mg2+ y Ca2+ sérico por espectofotómetría de absorción atómica. En heces, se realizó el recuento de huevos de helmintos por gramo (hpg) y la diferenciación de géneros por coprocultivo.Las UPF tuvieron en promedio 91,4±75 caprinos (sin contar cabritos), siendo el 80,9% cabras madres. La cría fue extensiva con encierre nocturno y la alimentación de la majada se basó mayormente en el pastoreo de los cerros y de cultivos y rastrojos. La parición se concentró en dos períodos, uno principal en abril-julio y una segunda parición de menor número de cabras ubicada en octubre-diciembre. El 92,3% de los productores desparasitaba en forma rutinaria toda la majada con ivermectina, albendazole o closantel y el 71,8 % trataba los piojos. En un 61,5% de las UPF se inyectaba mineralizantes-vitamínicos a toda la majada y en solo un 15,4% se vacunaba contra enfermedades clostridiales. El promedio de la tasa de mortalidad anual por majada fue del 14,2±11%. En el 86,4% de las UPF se registró la ocurrencia de abortos, y de estos el 42,9% presentó retención de placenta. El promedio intramajada de abortos comunicados fue del 8,6±8,5%. El 75% de las UPF declaró tener ectima contagioso, aunque solo el 22% dijo que era grave. Se registraron un 30,4% cuadros de muertes agudas probablemente por infecciones clostridiales. En el 72,7% de las UPF se registraron problemas de mastitis. El porcentaje de UPF con seroprevalencia positiva a brucelosis, leptospirosis, paratuberculosis, toxoplasmosis, clamidiosis, CpHV-1, CAEV y fiebre Q fue respectivamente de 0%, 25%, 50%, 42,8%, 88,8%, 85,7%, 12,5% y 0%. Las UPF destacaron la importancia de los piojos (Linognathus spp.: 87%). Los promedios de los hpg fueron en abril-mayo, julio-agosto y septiembre-noviembre respectivamente de 407, 332 y 59 con Haemonchus y en menor medida Trichostrongylus como nematodes predominantes. En el 76% de las UPF se diagnosticó Fasciolosis. El 30,8% de las UPF describió la presencia a la faena de quistes hidatídicos. En un 31% de las majadas se describió bocio. Los promedios por UPF de cobre, zinc, magnesio y calcio séricos fueron respectivamente 0,48 ±0,10 ppm, 0,73±0,16 ppm, 2,4±0,47mg/d y 7,25±2,25 mg/dl. Se describieron casos de timpanismo espumoso (43,5%), muertes (36%) atribuidas por los propietarios a la ingesta de ñusco, mio mio y sunchillo y un 38,1% de las UPF dijeron padecer casos de intoxicación con cegadera (Heterophyllaea pustulata). Un 66,7% de los propietarios declararon tener problemas de pérdidas de animales en el monte a causa mayormente de pumas. Estos primeros resultados en cuanto a mortandad y presencia de enfermedades y zoonosis, muestran la importancia de llevar a cabo estudios más específicos respecto de la salud de las majadas para incrementar la producción y el bienestar general de las familias productoras.Fil: Suarez, V. H.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Dodero, Ana Mariela. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nievas, J. D.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Martinez, G. M.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; ArgentinaFil: Bertoni, E. A.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Salatin, A. O.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Viñabal, A. E.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Grossberger, G.. No especifíca;Fil: Brihuega, Bibiana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Romera, Sonia. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pinto, G.. Instituto Nacional de Tecnología Agropecuaria; Argentin
Examining the generalizability of research findings from archival data
This initiative examined systematically the extent to which a large set of archival research findings generalizes across contexts. We repeated the key analyses for 29 original strategic management effects in the same context (direct reproduction) as well as in 52 novel time periods and geographies; 45% of the reproductions returned results matching the original reports together with 55% of tests in different spans of years and 40% of tests in novel geographies. Some original findings were associated with multiple new tests. Reproducibility was the best predictor of generalizability—for the findings that proved directly reproducible, 84% emerged in other available time periods and 57% emerged in other geographies. Overall, only limited empirical evidence emerged for context sensitivity. In a forecasting survey, independent scientists were able to anticipate which effects would find support in tests in new samples
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data
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Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients (PROBESE): study protocol for a randomized controlled trial
Background: Postoperative pulmonary complications (PPCs) increase the morbidity and mortality of surgery in obese patients. High levels of positive end-expiratory pressure (PEEP) with lung recruitment maneuvers may improve intraoperative respiratory function, but they can also compromise hemodynamics, and the effects on PPCs are uncertain. We hypothesized that intraoperative mechanical ventilation using high PEEP with periodic recruitment maneuvers, as compared with low PEEP without recruitment maneuvers, prevents PPCs in obese patients. Methods/design The PRotective Ventilation with Higher versus Lower PEEP during General Anesthesia for Surgery in OBESE Patients (PROBESE) study is a multicenter, two-arm, international randomized controlled trial. In total, 2013 obese patients with body mass index ≥35 kg/m2 scheduled for at least 2 h of surgery under general anesthesia and at intermediate to high risk for PPCs will be included. Patients are ventilated intraoperatively with a low tidal volume of 7 ml/kg (predicted body weight) and randomly assigned to PEEP of 12 cmH2O with lung recruitment maneuvers (high PEEP) or PEEP of 4 cmH2O without recruitment maneuvers (low PEEP). The occurrence of PPCs will be recorded as collapsed composite of single adverse pulmonary events and represents the primary endpoint. Discussion To our knowledge, the PROBESE trial is the first multicenter, international randomized controlled trial to compare the effects of two different levels of intraoperative PEEP during protective low tidal volume ventilation on PPCs in obese patients. The results of the PROBESE trial will support anesthesiologists in their decision to choose a certain PEEP level during general anesthesia for surgery in obese patients in an attempt to prevent PPCs. Trial registration ClinicalTrials.gov identifier: NCT02148692. Registered on 23 May 2014; last updated 7 June 2016. Electronic supplementary material The online version of this article (doi:10.1186/s13063-017-1929-0) contains supplementary material, which is available to authorized users
Primer aislamiento de Leptospira borgpetersenii de un feto de jabalí (Sus scrofa)
La leptospirosis es una zoonosis mundial y es endémica en muchos países. Esta enfermedad se mantiene en la naturaleza por la infección renal crónica de los animales portadores; los roedores y otros mamíferos pequeños son los reservorios más importantes. Además, otras fuentes importantes de infección para el humano son los animales domésticos, como el ganado y los perros. El jabalí (Sus scrofa) es una especie introducida de Europa que está muy extendida en América y particularmente en el centro y sur de Argentina. Esta especie es muy valorada por los cazadores de la región y su carne se consume con mayor frecuencia. En muchos países del mundo (Europa, EE. UU. y Australia) se han realizado estudios sobre seroprevalencia, la seroreactividad no significa que el jabalí manifieste síntomas clínicos de leptospirosis o que los jabalíes sean reservorios de este patógeno bacteriano. Sin embargo, estos animales han estado en contacto con leptospiras en su entorno en el pasado. Este estudio tiene el objetivo de tipificar molecularmente la cepa aislada obtenida a partir de 4 fetos de jabalíes (Sus scrofa) provenientes de la Patagonia argentina. Se realizaron necropsias de los 4 fetos y se cultivaron muestras de riñones, hígado, bazo y pulmón en medios Fletcher y EMJH. Además, las muestras de hígado, bazo, pulmón y riñón de los fetos se procesaron y analizaron por inmunofluorescencia directa. Se utilizó el análisis de repeticiones en tándem de número variable de locus múltiple (MLVA) para caracterizar la cepa aislada. El perfil genético de la cepa de leptospira fue idéntica al perfil de Leptospira borgpetersenii serovar Castellonis Castellon 3 perteneciente al serogrupo Ballum. Hasta donde sabemos, este es el primer aislamiento de Leptospira spp. de un feto de jabalí
Comprehensive flow cytometric reference intervals of leukocyte subsets from six study centers across Europe
A group of European FOCIS Centers of Excellence adapted panels of the Human Immunophenotyping Consortium (HIPC) for whole blood analysis. Using four core panels [T/regulatory T cell/B/natural killer (T/Treg/B/NK) and myeloid cells] the main leukocyte populations were analyzed in a clinical-diagnostic setting in a harmonized manner across different platforms. As a first step, the consortium presents here the absolute and relative frequencies of the leukocyte subpopulations in the peripheral blood of more than 300 healthy volunteers across six different European centers