Evaluation of bleach-sedimentation for sterilising and concentrating Mycobacterium tuberculosis in sputum specimens

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Bleach-sedimentation may improve microscopy for diagnosing tuberculosis by sterilising sputum and concentrating Mycobacterium tuberculosis. We studied gravity bleach-sedimentation effects on safety, sensitivity, speed and reliability of smear-microscopy. Methods This blinded, controlled study used sputum specimens (n = 72) from tuberculosis patients. Bleach concentrations and exposure times required to sterilise sputum (n = 31) were determined. In the light of these results, the performance of 5 gravity bleach-sedimentation techniques that sterilise sputum specimens (n = 16) were compared. The best-performing of these bleach-sedimentation techniques involved adding 1 volume of 5% bleach to 1 volume of sputum, shaking for 10-minutes, diluting in 8 volumes distilled water and sedimenting overnight before microscopy. This technique was further evaluated by comparing numbers of visible acid-fast bacilli, slide-reading speed and reliability for triplicate smears before versus after bleach-sedimentation of sputum specimens (n = 25). Triplicate smears were made to increase precision and were stained using the Ziehl-Neelsen method. Results M. tuberculosis in sputum was successfully sterilised by adding equal volumes of 15% bleach for 1-minute, 6% for 5-minutes or 3% for 20-minutes. Bleach-sedimentation significantly decreased the number of acid-fast bacilli visualised compared with conventional smears (geometric mean of acid-fast bacilli per 100 microscopy fields 166, 95%CI 68-406, versus 346, 95%CI 139-862, respectively; p = 0.02). Bleach-sedimentation diluted paucibacillary specimens less than specimens with higher concentrations of visible acid-fast bacilli (p = 0.02). Smears made from bleach-sedimented sputum were read more rapidly than conventional smears (9.6 versus 11.2 minutes, respectively, p = 0.03). Counting conventional acid-fast bacilli had high reliability (inter-observer agreement, r = 0.991) that was significantly reduced (p = 0.03) by bleach-sedimentation (to r = 0.707) because occasional strongly positive bleach-sedimented smears were misread as negative. Conclusions Gravity bleach-sedimentation improved laboratory safety by sterilising sputum but decreased the concentration of acid-fast bacilli visible on microscopy, especially for sputum specimens containing high concentrations of M. tuberculosis. Bleach-sedimentation allowed examination of more of each specimen in the time available but decreased the inter-observer reliability with which slides were read. Thus bleach-sedimentation effects vary depending upon specimen characteristics and whether microscopy was done for a specified time, or until a specified number of microscopy fields had been read. These findings provide an explanation for the contradictory results of previous studies.Peer Reviewe

Los desafíos globales de la larga COVID-19 en adultos y niños

Durante los últimos tres años y medio (2020–2023), la enfermedad por coronavirus 2019 (COVID-19), causada por el síndrome respiratorio agudo severo coronavirus 2 (SARS-CoV-2), generó una emergencia inter-nacional, definida como Emergencia Sanitaria de Preocu-pación Internacional (PHEIC) y posteriormente declarada pandemia por la Organización Mundial de la Salud (OMS)

Infectious diseases prevention and vaccination in migrants in Latin America: The challenges of transit through the treacherous Darien gap, Panama

Carlos Espinal, Jose Brea, Juan-Carlos Navarro, Virgilio Gaston Lezcano, Marielys Otero-Maldonado, Rene Echevarría-Cofiño, Baruch Diaz, Pasesa Pascuala Quispe-Torrez, Rodrigo Nogueira Angerami, Maria L. Avila-Aguero, Roberto Debbag, Maria Eugenia Guevara, Yenddy Carrero, Carlos N. Torres-Martinez, Francisco Javier Membrillo, Jose A. SuarezHuman migration is a dynamic, multifaceted and complex phenomenon shaped by economic, political, social, climatic and environmental factors [1–4]. Migration refers to the relocation of individuals from their habitual residence to a new location, while travel involves journeying between destinations for various purposes [5]. In recent years, migration trends have been shaped by globalisation, technological advancements, climate change, armed conflicts, social and economic disparities and political and religious persecution. Migration poses challenges for individual nations and represents a crucial humanitarian and global health issue requiring coordinated international efforts and long-term planning [6–8].Versión publicad

Colombian consensus recommendations for diagnosis, management and treatment of the infection by SARS-COV-2/ COVID-19 in health care facilities - Recommendations from expert´s group based and informed on evidence

La Asociación Colombiana de Infectología (ACIN) y el Instituto de Evaluación de Nuevas Tecnologías de la Salud (IETS) conformó un grupo de trabajo para desarrollar recomendaciones informadas y basadas en evidencia, por consenso de expertos para la atención, diagnóstico y manejo de casos de Covid 19. Estas guías son dirigidas al personal de salud y buscar dar recomendaciones en los ámbitos de la atención en salud de los casos de Covid-19, en el contexto nacional de Colombia

Impacto del cambio climático en la remoción en masa del municipio de Villavicencio

The landslides is a mountain debris displacement phenomenon due mainly to the gravity force action in these debris, however when the rainy station occur the rainfall affects the mechanical characteristics of the mountain slope because in same time occur in this rainfall, evaporation and increase of permeability in the sediments. In Villavicencio, Colombia, which is a city with eight communes or municipal legality areas, for three of these are high affectation by landslides because to that many of their neighborhoods are over mountain slopes increase of this manner its vulnerability to this natural hazard. The analyzed area in this work correspond to the Commune 2 which have very poor neighborhoods due to illegal soil occupation and that exposes to its inhabitants to this natural hazard.La remoción en masa es el fenómeno de desplazamiento de volúmenes de material de ladera debido básicamente a la acción producida por la fuerza de gravedad en dicho volúmenes, sin embargo cuando ocurren periodos de lluvia, esta precipitación afecta las características mecánicas del talud ya que interactúan los parámetros de precipitación, evaporación e infiltración. El municipio de Villavicencio se divide en ocho comunas de las cuales tres cuentan con barrios ubicados cerca del pie de la cordillera, zonas que presentan grandes pendientes que incrementan su vulnerabilidad a la remoción de masa. La zona analizada aquí corresponde a la comuna 2 la cual presenta asentamientos subnormales por ocupación ilegal, situación que produce alta susceptibilidad a la ocurrencia de este fenómeno

Impacto del cambio climático para el municipio de Villavicencio: una revisión

The climate system is a highly complex system and this has five main elements: atmosphere, hydrosphere, lithosphere, cryosphere, and biosphere. Its complex behavior is due to the interactions between them. The origin of the climate dynamics is in the Sun activity, together with oceanic currents circulation and volcanic activity. This climatological evaluation was realized in the city of Villavicencio taking the data presented between 1983 and 2012 registered by the main weather station (CP) Unillanos located in the Barcelona town near to urban area. As results of this evaluation is found significant changes for climatic variables like precipitation, temperature, sunshine, relative humidity and evaporation.El sistema climático es un sistema altamente complejo integrado por cinco grandes componentes: atmósfera, hidrosfera, litosfera, criósfera, la biosfera y las interacciones entre ellos. La atmósfera con sus componentes principales es forzada desde el espacio exterior y desde la superficie terrestre por distintos procesos internos y externos. Se realizó la evaluación climatológica en el municipio de Villavicencio tomando los registros presentados en la estación climatología principal (CP) Unillanos ubicada en la vereda Barcelona dentro de los años 1983 y 2012 encontrando cambios significativos en las variables climatológicas: precipitación, temperatura, brillo solar, humedad relativa y evaporación

Prototype design of extremely low frequency magnetic radiator for inhibition of in vitro growth of Ralstonia solanacearum

La marchitez bacteriana de la papa, es una enfermedad cuyo agente causal es Ralstonia solanacearum, bacteria Gram negativa. Sus principales hospederos pertenecen al género Solanum,en donde el porcentaje de afección sobre cultivos específicos como los de Solanum tuberosum (papa o patata) es del 100\%. Actualmente las medidas preventivas que se han tomado para evitar su presencia, se han realizado mediante la siembra de semillas sanas, plantación en suelos sin antecedentes de la presencia de Ralstonia solanacearum, uso de aguas de riego sin contaminación, rotación de cultivos entre otros procesos que se le practican al manejo de cultivos (Ica,2011). Cuando se verifica su presencia hace manejo de agroquímicos, los cuales pueden ser perjudiciales para el ecosistema, la salud humana y animal, como es el caso conocido del Metam sodio (Eastman Chemical Company 2005). Se han realizado estudios sobre la implementación de antibióticos para esta bacteria, los cuales tuvieron como resultado resistencia después de 10 días. Teniendo en cuenta lo anterior este proyecto realizó el diseño de un prototipo radiador de campos electromagnéticos. Se realizaron simulaciones en el programa CST studios, el cual permitió visualizar de forma interactiva la formación del campo magnético con las variables de frecuencia e intensidad de corriente estipulados en los requerimiento de la bacteria, además se simuló la interacción del campo magnético con un objeto metálico en el que se determinó que la distancia mínima en la que se debe encontrar el objeto es de 15 cm dentro y fuera del soporte de las bobinas. Al realizar las pruebas de funcionamiento del dispositivo se obtuvo que el campo magnético promedio generado es de 51.48 T, +/- 2.7, utilizando una frecuencia de 50 Hz y una intensidad de corriente de 0.038 A. Adicionalmente, se realizó un protocolo de implementación del dispositivo con microorganismos de forma in vitro el cual permitirá realizar investigaciones sobre los efectos de los campo magnéticos en bacterias Gram negativas, modificando la corriente que pasa por las bobinas además de la frecuencia, dependiendo del organismos que se quiera irradiar.BioingenieroPregradoBacterial wilt is an illness caused by Ralstonia solanacearum as its agent, a Gram-negative bacteria. The main host belongs to the \emph{Solanum} genus, affecting a 100\% of specific crops of Solanum tuberosum (know as potatoes). Currently, this agent has been treated through good farming practices and chemicals which might be harmful to the ecosystem and human health. Studies about this bacteria have been conducted in order to find a new form to treat it using antibiotics, resulting in a reported resistance after 10 days. This project designed a prototype of electromagnetic field radiator. To develop this it was necessary to make a series of simulations using Computer Simulation Technology (CST) Studio Suite, which allowed to visualize the formation of the magnetic field with the variables of frequency and current stipulated in requirements of the bacterium,in addition we simulated the interaction between the magnetic field and a metallic object, it determinates the minimum distance in which the object must to be place is 15 cm inside and outside of the coil holder. Carrying out with the functional tests of the device, we obtained that the average of the magnetic field generated is 51.48 T, +/- 2.7, using a frequency of 50 Hz and current intensity of 0.038A. Additionally, we develop a implementation protocol of the device, which will allow to carry out investigations of the effects of magnetic fields in Gram negative bacteria, modifying the current that passes through the coils, those changes dependence on the organisms that you want to irradiate

Comercial Indurama

Una niña que prepara unos sándwiches está en la cocina acompañando a su mama mientras ella prepara una torta con nevera y estufa Indurama. La mamá termina de alistar la torta y la mete dentro del horno de la estufa Indurama. La niña observa unos ingredientes que hay sobre el mesón, (en este momento la imagen cambia, la luz se calienta un poco y aparece una viñeta difuminada). Con tajadas de pan y ayudándose de algunos vegetales forma la figura de un pez, un barco y una isla.PregradoProfesional en Dirección y producción de medios audiovisuale

Urban Drainage Water Quality Modeling on the SWMM Software, Northeastern Sector, Santa Inés District, Tunja

Objective:This research aimed to design a drainage quality hydrodynamic model of the northeastern sector of Tunja (San-ta Inés neighborhood), Boyacá, Colombia, which was validated and calibrated by means of the mean square error method,where a comparison between the values observed in the field and the simulation results in the model was determined inorder to observe and analyze the effect of precipitation on pollutants before entering the treatment plant.Methodology:For this study, rainfall and water flow equipment were installed in the district. A validated and calibratedurban drainage model was created on the SWMM 5.1 software, which allowed a temporal hydrodynamic modeling of thesystem. In addition, samples were taken to determine the quality of the water arriving at the treatment plant and evaluatethe transportation of pollutants, as well as the possibility of hydrogen sulfide generation in the study area.Results:The results obtained with the model show that all pollutants generate drag in their concentrations. An excess ofthese values is observed within the total flow, which demonstrates the relevance of accumulation, washing, and transportprocesses, in light of the pollutant remnants causing the flow to decrease before the pollutant load.Conclusions:Our sampling indicates that it is necessary to analyze the coliforms present in wastewater discharges, as wellas the sulfate, nitrite, and nitrate values in the case of a specific discharge. The entity in charge of discharge control mustbe then informed.Financing:Universidad Santo Tomas - Tunj