Biocide effect against SARS-CoV-2 and ESKAPE pathogens of a noncytotoxic silver-copper nanofilm.

Nanometric materials with biocidal properties effective against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) and pathogenic bacteria could be used to modify surfaces, reducing the risk of touching transmission. In this work, we showed that a nanometric layer of bimetallic AgCu can be effectively deposited on polypropylene (PP) fibers. The virucidal properties of the AgCu nanofilm were evaluated by comparing the viral loads remaining on uncoated and coated PP after contact times between 2 and 24 h. Quantification of virion numbers for different initial concentrations indicated a reduction of more than 95% after 2 h of contact. The bactericidal action of the AgCu nanofilm was also confirmed by inoculating uncoated and coated PP with a pool of pathogenic bacteria associated with pneumonia (ESKAPE). Meanwhile, no cytotoxicity was observed for human fibroblasts and keratinocyte cells, indicating that the nanofilm could be in contact with human skin without threat. The deposition of the AgCu nanofilm on the nonwoven component of reusable cloth masks might help to prevent virus and bacterial infection while reducing the pollution burden related to the disposable masks. The possible mechanism of biocide contact action was studied by quantum chemistry calculations that show that the addition of Ag and/or Cu makes the polymeric fiber a better electron acceptor. This can promote the oxidation of the phospholipids present at both the virus and bacterial membranes. The rupture at the membrane exposes and damages the genetic material of the virus. More studies are needed to determine the mechanism of action, but the results reported here indicate that Cu and Ag ions are good allies, which can help protect us from the virus that has caused this disturbing pandemic.

Fabrication and in vitro behavior of dual-function chitosan/silver nanocomposites for potential wound dressing applications.

We report the synthesis and in vitro evaluation of dual-function chitosan-silver nanoparticles (CTS-AgNPs) films with potential applications as wound dressings. We attempted to formulate nanocomposite films with appropriate AgNPs concentrations to simultaneously display antibacterial activity and suitability for cell culture. Nanocomposites were obtained by CTS-mediated in situ chemical reduction of AgNO3. Circular-shape AgNPs (sizes ca. 7-50 nm) well distributed within the CTS matrices were obtained in concentrations from 0.018 to 0.573 wt%. Efficacy (bacteriostatic and bactericidal properties) of CTS-AgNPs films to decrease planktonic and biofilm bacterial growth was AgNPs concentration- and bacteria strain-dependent. Films showed significant antibacterial activity against Gram-negative E. coli and P. aeruginosa and Gram-positive S. aureus. Antibacterial activity against S. epidermidis was moderated. Films suitability for cell culture was characterized using primary human fibroblasts (HF). HF displayed cell viability higher than 90% and the characteristic fusiform morphology of adhered fibroblast upon culture on films with AgNPs concentration ≤ 0.036 wt%. HF cultured on these films also showed positive expression of tropoelastin, procollagen type I and Ki-67, characteristic proteins of extracellular matrix and proliferative cells, respectively. In vitro assays demonstrated that cytocompatibility/antibacterial properties decreased/increased as silver concentration increased, suggesting that CTS-AgNPS nanocomposite films with ≈0.04-0.20 wt% might be considered as potential temporary dual-function wound dressings.

Análisis bibliométrico de los artículos originales publicados en la revista Ciencia & Trabajo: 1999-2015 / Bibliometric analysis of the original articles published in the journal Ciencia & Trabajo: 1999-2015

INTRODUCCIÓN: La Revista Ciencia y Trabajo (C&T) es editada por la Fundación Científica y Tecnológica de la Asociación Chilena de Seguridad desde 1999, publica trabajos científicos en temas relaciona dos con la seguridad e higiene industrial, salud ocupacional, calidad de vida laboral y otras disciplinas asociadas al trabajo y medio ambiente. OBJETIVO: Analizar la producción científica de los artículos originales publicados en C&T durante el periodo 1999-2015. MATERIAL Y MÉTODOS: Estudio bibliométrico descriptivo, longitudinal y retrospectivo. Se analizaron las características metodológicas y técnicas específicas en pre vención de riesgos laborales para cada uno de los artículos analizados, asimismo, la visibilidad en SciELO Analytics para los últimos años. RESULTADOS: Se publicaron un total de 430 artículos originales en 52 números con una media de 27 ± 8,8 artículos por año y 8 ± 2,6 artícu los por número. Los años con más artículos fueron 2009, 2010 y 2011. El número de autores por artículo oscila entre 1 a 4 (82%), en su mayo ría de universidades de Latinoamérica, destacando Chile, México y Brasil como los países de mayor contribución. La Psicosociología y Medicina del Trabajo son las temáticas más investigadas respecto a otras técnicas específicas en prevención de riesgos laborales como la Seguridad en el Trabajo y Ergonomía, predominando los estudios trans versales de carácter descriptivo-observacional en el idioma español. CONCLUSIONES: Se evidencia la consolidación de la revista a lo largo del tiempo. Por la antigüedad, publicación regular y demás atributos, la Revista C&T puede plantearse la posibilidad de ser indexada en la base de datos Scopus.

BACKGROUND: The journal Science and Work (C&T) has been pub lished by the Scientific and Technological Foundation of the Chilean Security Association since 1999, it publishes scientific papers on issues related to industrial safety and health, occupational health, quality of work life and other disciplines associated with Work and the environment. Objetive: To analyze the scientific production of the original articles published in C&T during the period 1999-2015. MATERIALS-METHODS: Descriptive, longitudinal and retrospective bibliometric study. We analyzed the specific methodological and technical characteristics in occupational risk prevention for each of the analyzed articles, as well as the visibility in SciELO Analytics for the last years. RESULTS: A total of 430 original articles were published in 52 numbers with an average of 27 ± 8.8 articles per year and 8 ± 2.6 articles per number, the years with the most articles were 2009, 2010 and 2011. The number of authors per article ranges from 1 to 4 (82%), mostly from Latin American universities, Chile, Mexico and Brazil being the countries with the highest contribution. Psychosociology and Occupational Medicine are the most researched topics in relation to other specific techniques in the prevention of occupational hazards such as Occupational Safety and Ergonomics, with cross - sectional descriptive - observational studies predominat ing in the spanish language. CONCLUSIONS: It is evident the consolida tion of the journal over time. Due to seniority, regular publication and other attributes, C&T can consider the possibility of being indexed in the Scopus database.

SUSCEPTIBILIDAD ANTIMICROBIANA DE AISLAMIENTOS DE Salmonella entérica PROVENIENTES DE PISOS, EQUIPOS, UTENSILIOS Y PRODUCTO TERMINADO EN PLANTAS DE BENEFICIO PORCINO EN COLOMBIA / ANTIMICROBIAL SUSCEPTIBILITY OF Salmonella enterica STRAINS ISOLATED FROM FLOORS, EQUIPMENT, MACHINERY, AND FINISHED PRODUCT IN PORCINE SLAUGHTERHOUSES IN COLOMBIA

La diseminación de Salmonella spp. resistente a antimicrobianos en las cadenas productivas de alimentos de origen animal es una preocupación de salud pública de carácter mundial. Este estudio describe los patrones de resistencia antimicrobiana de 283 aislamientos de Salmonella enterica procedentes de plantas de beneficio porcino en Colombia. Se evaluó la susceptibilidad antimicrobiana frente a diez antimicrobianos mediante el método de difusión en disco: amoxacilina-ácido clavulánico (30 ug), ampicilina (10 ug), ceftiofur (30 ug), ciprofloxacina (5 ug), cloranfenicol (30 ug), florfenicol (30 ug), gentamicina (10 ug), sulfadiazina/trimetroprim (25 ug), tetraciclina (30 ug) y tilmicosina (15 ug). Los resultados evidenciaron la presencia de 279 aislamientos multirresistentes de Salmonella enterica de origen porcino provenientes del ambiente y del producto terminado en las plantas de beneficio evaluadas (46,64% n: 132). Se detectaron 52 patrones de multiresistencia: el más común fue ceftiofur-tetraciclina-tilmicosina en el 9,89% (n: 28) de los aislamientos. Con referencia a estos antimicrobianos, 96,82% (n: 274) de los aislamientos fueron resistentes a tetraciclina, 73,14% (n: 207) a tilmicosina y 28,27% (n: 80) a ceftiofur. De especial interés fue la alta proporción de aislamientos resistentes a ceftiofur, debido a una posible resistencia cruzada con ceftriaxona. Los resultados obtenidos demuestran la necesidad de promover el diseño e implementación de un Programa oficial Integrado de Vigilancia de la Resistencia Antimicrobiana, además de sistemas de monitoreo voluntario en cada eslabón de la cadena productiva porcina, para contribuir a la prevención y control de la transmisión de microorganismos resistentes de origen alimentario en el marco del sistema de gestión de inocuidad alimentaria en Colombia.

The development and spread of antimicrobial multidrug resistance_of Salmonella spp. from food chain is a public health concern global. This study aimed to describe the antimicrobial resistance patterns of 283 isolates of Salmonella enterica from pork slaughterhouse in Colombia. Antimicrobial susceptibility on ten antimicrobials was evaluated: amoxicillin - clavulanic acid (30 ug), ampicillin (10 ug), ceftiofur (30 ug), ciprofloxacin (5 ug), chloramphenicol (30 ug), florfenicol (30 ug), gentamicin (10 ug), sulfadiazine/trimethoprim (25 ug), tetracycline (30 ug) and tilmicosin (15 ug) using the disc diffusion method. The results showed the high presence of isolates multidrug resistant of Salmonella enterica widespread on environmental of slaughterhouse (46.64% n: 132). 52 multidrug resistance patterns were detected. The most common was ceftiofur - tetracycline - tilmicosin in 9.89% (n = 28) of isolates. These same three antimicrobials were less effective with 96.82 % (n = 274) resistant-isolates against tetracycline, 73.14 % (n = 207) against tilmicosin and 28.27 % (n = 80) against ceftiofur. Of particular concern was the high rate of resistance to ceftiofur due to its cross-resistance to ceftriaxone. The results demonstrate the need to promote and strengthen an official Integrated Program for Antimicrobial Resistance Surveillance and volunteer monitoring systems in each link of the porcine production chain, to contribute to the prevention and control of food-borne infections in the context of safety management system in Colombia.

Biodegradation of paper waste under controlled composting conditions.

The presence of paper in municipal solid waste (MSW) interferes with the efficiency of composting plants. The compost feedstock to these plants is between 12% and 27% paper on a dry weight basis, with an initial C:N ratio ranging from 32:1 to 57:1. Tests of the last aerobic biodegradability (LAB) of the type of paper present in paper and cardboard packaging were carried out, following UNE-EN 14046 standards. The results obtained, measured through the quantity of CO(2) generated over 45 days, compared with the maximum that could be produced (ThCO(2)), showed that the presence of paper retards, to a great degree, the biodegradation of organic material in general. Specifically, the presence of papers with a degradation D (%) >60% at 45 days (white (W) and recycled paper (R)) could be allowed, but always in proportions that did not exceed 27% in dry weight. These results can be achieved with an industrial level process, pre-treated by trituration.

[Mycoplasma genitalium detection and correlation with clinical manifestations in population of the Zulia State, Venezuela]. / Detección de Mycoplasma genitalium y correlación con manifestaciones clínicas en una población del estado Zulia, Venezuela.

Diverse studies demonstrate an association between Mycoplasma genitalium and urogenital pathologies. The aim of this study was to investigate the prevalence of M. genitalium in patients attending gynecological evaluation in private clinics (n = 172). DNA amplification assays of the genes 16S rRNA and MgPa were utilized. The prevalence of M. genitalium in the study population was 7.5%. M. genitalium was detected in 12.1% and 4.1% of the symptomatic and asymptomatic patients, respectively (p = 0.047). The infection was diagnosed in patients with cervicitis (17.2%) and mucopurulent secretion (16.6%) and the highest prevalence of infections was registered in the 31-40 years age group. No significant association between the presence of M.genitalium and individual clinical manifestations or the patients age was showed (p > 0.05). The high prevalence of M. genitalium infections, mostly in patients with clinical manifestations showed in this study, warrants the application of diagnostic strategies in the population to investigate the clinical meaning of these microorganisms and to reevaluate therapeutic schemes against non-gonococcal and non-chlamydial infections.

Detección de Mycoplasma genitalium y correlación con manifestaciones clínicas en una población del estado Zulia, Venezuela / Mycoplasma genitalium detection and correlation with clinical manifestations in population of the Zulia State, Venezuela

Diverse studies demonstrate an association between Mycoplasma genitalium and urogenital pathologies. The aim of this study was to investigate the prevalence of M. genitalium in patients attending gynecological evaluation in private clinics (n = 172). DNA amplification assays of the genes 16S rRNA and MgPa were utilized. The prevalence of M. genitalium in the study population was 7.5 percent. M. genitalium was detected in 12.1 percent and 4.1 percent of the symptomatic and asymptomatic patients, respectively (p = 0.047). The infection was diagnosed in patients with cervicitis (17.2 percent) and mucopurulent secretion (16.6 percent) and the highest prevalence of infections was registered in the 31-40 years age group. No significant association between the presence of M.genitalium and individual clinical manifestations or the patients age was showed (p > 0.05). The high prevalence of M. genitalium infections, mostly in patients with clinical manifestations showed in this study, warrants the application of diagnostic strategies in the population to investigate the clinical meaning of these microorganisms and to reevaluate therapeutic schemes against non-gonococcal and non-chlamydial infections.

Diversos estudios demuestran una asociación entre Mycoplasma genitalium y patologías urogenitales. El objetivo de este trabajo fue investigar la prevalencia de infecciones por M. genitalium en pacientes atendidas en clínicas privadas (n = 172). Se utilizaron ensayos de amplificación de genes 16S rARN y MgPa. La prevalencia de M. genitalium en esta población fue 7,5 por ciento. Mycoplasma genitalium fue detectado en 12,1 y 4,1 por ciento) de las pacientes sintomáticas y asintomáticas, respectivamente (p = 0,047). La infección se diagnosticó en pacientes con cervicitis (17,2 por ciento) y con secreción mucopurulenta (16,6 por ciento) y la mayor prevalencia de infecciones se registró en el grupo etario de 31 a 40 años. No se encontró asociación significativa entre la presencia de M. genitalium y manifestaciones clínicas individuales o edad de las pacientes (p > 0,05). La alta prevalencia de infecciones por M. genitalium, principalmente en pacientes con manifestaciones clínicas demostrada en este estudio, demanda la aplicación de estrategias diagnósticas en la población para investigar el significado clínico de estos microorganismos y reevaluar esquemas terapéuticos contra infecciones no gonocóccicas y no clamidiales.

Estado actual de la formación de residentes de cirugía general en Colombia / Current state of general surgical training programs in Colombia

Introducción: La formación y certificación de Cirujanos es una preocupación creciente en los programas de Cirugía en Colombia, sin embargo no existe un diagnostico de la situación actual que permita un ajuste a los cambios constantes. Describimos en términos de carga académica y laboral el estado actual de los programas de residencia de Cirugía General inicialmente en la ciudad de Bogotá y en una segunda fase extenderlo al resto del país, desde la perspectiva de los residentes. Materiales y métodos: Se aplicó una encuesta a los residentes activos de Cirugía General en Bogotá y se tabularon los resultados en una base de datos Excel. Resultados: Se obtuvo información completa del 97.6 porciento de la población de residentes de Cirugía General en Bogotá, Clasificándola en cuatro variables: Datos sociodemográficos, información asistencial y académica, satisfacción y expectativa laboral. Conclusiones: El análisis de los datos muestra que los residentes de cirugía General se encuentran satisfechos con el programa donde realizan su especialización, sin embargo, no disponen de facilidades para que la investigación clínica termine en publicaciones, y el bienestar de los residentes no es una prioridad.

Magnetic resonance imaging of the intrauterine fetal genitourinary tract: normal anatomy and pathology.

Although ultrasonography (US) remains the most widely used diagnostic imaging modality for routine evaluation of the fetus, magnetic resonance (MR) imaging has become an invaluable complement to US in all cases in which additional information is desirable. While the ability of US to detect fetal abnormalities is limited in cases such as maternal obesity, oligohydramnios, and in certain fetal positions, MR using fast and ultrafast pulse sequences enables high-quality fetal images to be acquired regardless of the mother's physical condition or fetal position. Fetal genitourinary disorders are the most common intrauterine abnormalities detected by US, accounting for approximately 30% of all antenatally detected anomalies. Although they usually occur in isolation, these defects can form part of more complex syndromes or chromosomopathies, and MR is indicated to rule out associated abnormalities. In some severe genitourinary disorders, there is a severe deficit of amniotic fluid; these cases are associated with other fetal anomalies such as pulmonary hypoplasia and very poor prognosis. In other cases, the amniotic fluid is not compromised, yet the further detection, localization, and characterization of prenatal disorders will have an impact on postnatal follow-up. This article reviews the role of fetal MR in urogenital tract disorders.

Donación voluntaria de sangre dentro del ámbito universitario / Voluntary blood donation at the university

En medicina transfusional es importante conocer las actitudes, creencias y motivaciones de la población frente a la donación de sangre; esto ayuda a la captación de nuevos donantes y a retener a los existentes. Se entregaron 3000 encuestas junto con las fichas de salud a cada uno de los alumnos ingresantes a la Universidad Nacional del Sur en diciembre de 2001, recepcionándose las mismas hasta el mes de setiembre de 2002. Se dividió a la población en carreras humanísticas y técnicas, de acuerdo a si tenían o no asignaturas con actividades de laboratorio o manuales. Se confeccionó una base de datos para su posterior análisis estadístico. Entre los resultados obtenidos se halló una moderada predisposición a la donación entre los que nunca donaron ("sesgo de hipótesis") y muy poca predisposición entre los que sí lo hicieron anteriormente ("sesgo estratégico"). Se especula que el bajo número de donantes se debe entre otros motivos, a las carecterísticas etarias de la población estudiada (media de edad: 19 años). Por lo expuesto se considera que el ámbito universitario es un espacio adecuado para lograr el compromiso de los jóvenes con la donación voluntaria de sangre, razón por la cual es necesario implementar campañas de hemodonación.

Plasma thrombin-activatable fibrinolytic inhibitor (TAFI) among healthy subjects and patients with vascular diseases: a validation study.

Thrombin activable fibrinolysis inhibitor antigen levels (TAFI Ag ) exhibit a great inter-individual variability in healthy populations. Our aim is to determine whether variability is due to physiologic variations depending on genetic control or due to validation of the method,in order to allow a better interpretation of the results inpatients with vascular diseases. With this purpose, we performed a strategy validation of specific ELISA method, Zymutest TAFI Ag Hyphen Biomed, base don a commercial monoclonal antibody. After methodology validation we have recently determined plasma TAFI Ag levels in several groups of diseases such as septic patients, menopause and cerebrovascular diseases. TAFI was finally determined in acute ischemic stroke to know its relationship with stroke evolution and response to thrombolytic treatments.

Mitochondrial DNA analysis reveals substantial Native American ancestry in Puerto Rico.

To estimate the maternal contribution of Native Americans to the human gene pool of Puerto Ricans--a population of mixed African, European, and Amerindian ancestry--the mtDNAs of two sample sets were screened for restriction fragment length polymorphisms (RFLPs) defining the four major Native American haplogroups. The sample set collected from people who claimed to have a maternal ancestor with Native American physiognomic traits had a statistically significant higher frequency of Native American mtDNAs (69.6%) than did the unbiased sample set (52.6%). This higher frequency suggests that, despite the fact that the native Taíno culture has been extinct for centuries, the Taíno contribution to the current population is considerable and some of the Taíno physiognomic traits are still present. Native American haplogroup frequency analysis shows a highly structured distribution, suggesting that the contribution of Native Americans foreign to Puerto Rico is minimal. Haplogroups A and C cover 56.0% and 35.6% of the Native American mtDNAs, respectively. No haplogroup D mtDNAs were found. Most of the linguistic, biological, and cultural evidence suggests that the Ceramic culture of the Taínos originated in or close to the Yanomama territory in the Amazon. However, the absence of haplogroup A in the Yanomami suggests that the Yanomami are not the only Taíno ancestors.

Sexual dimorphism in the corpus callosum: methodological considerations in MRI morphometry.

Studies of sexual dimorphism in the corpus callosum (CC) have employed a variety of methodologies for measurement and normalization but have yielded disparate results. The present work demonstrates how in some cases different manipulations of the same raw data, corresponding to different commonly used methodologies, produce discordant results. Midsagittal CC area was measured from magnetic resonance images (MRIs) of 137 young normal volunteers. Three strategies intended to normalize for average differences in brain size between the sexes, as well as five different normalization variables, were contrasted and evaluated. The stereotaxic method normalizes for intersubject differences in overall brain size by scaling MRIs into a standardized space. The ratio method uses one of five different indices of brain size and divides it into CC area. The covariate method uses one of the indices as a covariate in statistical analyses. Male subjects show significantly larger absolute total area, as well as anterior third and posterior midbody. However, in two of three normalization strategies, namely the stereotaxic and ratio methods, females show relatively larger total area, anterior midbody, and splenium. The covariate method did not show any significant differences at the 0.05 level. Results suggest that different approaches to normalization and analysis are not necessarily equivalent and interchangeable.

In search of spatial extremes.

In environmental studies attention increasingly focuses on identification of spatial extremes: locations with observations that are apparently higher than either a preset background threshold or neighbouring observations. We consider various procedures for identifying values and locations of these extremes: extreme value theory, conditionally simulated fields and disjunctive kriging. In a recent research project we studied the distribution of nine environmental pollutants (heavy metals, polyaromatic hydrocarbons and mineral oil) in a large industrial estate in the southern Netherlands. This area is interesting as it is influenced by three contaminating processes: inundation by the river Meuse, anthropogenic heightening with contaminated materials and local industrial activities. Concentrations are measured. In this paper the peaks over threshold method was useful for finding extremes for spatially uncorrelated variables, whereas conditional simulations applied in particular to areas with spatial dependence.

Emotional responses to pleasant and unpleasant music correlate with activity in paralimbic brain regions.

Neural correlates of the often-powerful emotional responses to music are poorly understood. Here we used positron emission tomography to examine cerebral blood flow (CBF) changes related to affective responses to music. Ten volunteers were scanned while listening to six versions of a novel musical passage varying systematically in degree of dissonance. Reciprocal CBF covariations were observed in several distinct paralimbic and neocortical regions as a function of dissonance and of perceived pleasantness/unpleasantness. The findings suggest that music may recruit neural mechanisms similar to those previously associated with pleasant/unpleasant emotional states, but different from those underlying other components of music perception, and other emotions such as fear.

Inhibition of recombinant human mitochondrial aldehyde dehydrogenase by two intermediate metabolites of disulfiram.

Disulfiram is used in aversion therapy for alcoholism. S-Methyl-N,N-diethylthiocarbamate (MeDTC) sulfoxide, a potent inhibitor of the target enzyme mitochondrial aldehyde dehydrogenase (ALDH2), is thought to be the principal active metabolite of disulfiram in vivo. We examined the effects on recombinant human ALDH2 of two intermediate metabolites of disulfiram, S-methyl-N,N-diethyldithiocarbamate (MeDDC) sulfoxide and MeDDC sulfine. MeDDC sulfoxide was a potent inhibitor of ALDH2 with an IC50 of 2.2 +/- 0.5 microM (mean +/- SD, N = 4) after preincubation with enzyme for 30 min. MeDDC sulfine was a relatively weak inhibitor of ALDH2 under the same conditions with an IC50 value of 62 +/- 14 microM. The inhibition of ALDH2 by both compounds was irreversible and did not require the cofactor NAD. The latter finding demonstrates that inactivation of ALDH2 is independent of the dehydrogenase activity of the enzyme. GSH blocked almost completely the inhibition by 20 microM of MeDDC sulfoxide and greatly diminished the inhibition by 200 microM of MeDDC sulfine. Inactivation by MeDDC sulfoxide was time dependent. MeDTC sulfoxide was a more potent inhibitor of recombinant human ALDH2 (IC50 = 1.4 +/- 0.3 microM after preincubation for 15 min) than either of the intermediate metabolites, and its inhibition was unaffected by GSH. Our results suggest that these newer intermediate metabolites of disulfiram, especially the more potent MeDTC sulfoxide, have the potential to inhibit the target enzyme ALDH2 in patients receiving disulfiram. However, until the significance of the interactions of the inhibitors with GSH is more fully understood, the contribution of MeDDC sulfine and MeDDC sulfoxide to the pharmacological effects of disulfiram in vivo is uncertain.