Asociación de desórdenes músculo esqueléticos en región cervical, dorsal y lumbar y factores de riesgo psicosocial en conductores de vehículos de carga en una empresa de transporte terrestre en Bogotá, Colombia.

Este estudio buscó evaluar la asociación de desórdenes músculo esqueléticos en región cervical, dorsal y lumbar identificados mediante el Cuestionario Nórdico en su versión validada al español y los factores de riesgo psicosocial con el Cuestionario del contenido del trabajo (JCQ), en conductores de vehículos de carga de una empresa de transporte terrestre en Bogotá, Colombia; fue un estudio de corte transversal con la participación voluntaria de 125 conductores. Los resultados demostraron mayor prevalencia de trastornos músculo esqueléticos en región lumbar en los últimos 12 meses en el 36% de los participantes y en los últimos tres meses en región cervical con el 17.6%; la prevalencia de factores psicosociales arrojó trabajo de baja tensión en el 29.6%, trabajo activo 26.4%, trabajo con alta tensión 23.2% y trabajo pasivo con el 20.8%. El valor p fue mayor de 0,005 no hallándose asociaciones significativas de desórdenes músculo esqueléticos en región cervical, dorsal y lumbar con factores de riesgo psicosocial.

Prevalencia de síntomas osteomusculares en miembros superiores en trabajadores de un call center de Bogotá – Colombia durante el año 2015

Introducción: Los trastornos del aparato locomotor son una de las principales causas del ausentismo laboral y generan un gasto considerable para el sistema de gestión pública. Objetivo: Determinar la prevalencia de síntomas osteomusculares en miembros superiores y su relación con los factores ocupacionales en trabajadores de un Call Center de Bogotá – Colombia durante el año 2015. Metodología: Estudio de corte transversal donde se evaluó la prevalencia de los síntomas osteomusculares de miembros superiores, se utilizó como instrumento el ERGOPAR validado en España . Resultados: El grupo de estudio lo conformaron 223 trabajadores de un Call Center donde el género femenino fue el más frecuente (66,8%), el grupo etario predominante fue entre 21 y 25 años (30,5%). La prevalencia de los síntomas osteomusculares por molestia estimada, fue mayor en cuello/hombro (57%), seguido del síntoma en manos/muñecas (40,8%) y por ultimo codos (17%); contrario a la prevalencia de síntomas osteomusculares manifestados por dolor ya que fue mayor en manos/muñecas (35%), seguido de cuello/hombros (28,3%) y por último codo (6,7%), esta prevalencia fue mayor en trabajadores de género femenino que en los de género masculino. Respecto a las variables relacionadas con el género, se encontró que la prevalencia por presencia de dolor en cuello/hombro fue mayor en trabajadores de género femenino (p=0,005) de la misma manera que la prevalencia por presencia de dolor en manos/muñecas (p<0,001). Conclusiones: Los síntomas osteomusculares más prevalentes en los trabajadores del Call Center fueron en cuello/hombro y manos/muñeca con mayor frecuencia en los trabajadores del género femenino. Con el fin de eliminar o disminuir la aparición temprana de estos síntomas, se recomienda la implementación de medidas de prevención dirigidas no solo al trabajador sino a todos los factores que hagan parte del desarrollo de su tarea.

Relación de los factores laborales e individuales con la carga mental de los trabajadores de una institución minera (2014)

Objetivo: Establecer la relación de los factores laborales e individuales con la carga mental en los trabajadores del área de contratación y titulación minera y los de seguimiento y control en una institución minera durante el año 2014. Materiales y métodos: Estudio de corte transversal en 298 trabajadores que trabajan en una Institución Minera, en la ciudad de Bogotá. La identificación de los factores laborales e individuales relacionados con la carga mental se hizo mediante la aplicación de un cuestionario autodiligenciado utilizando la guía de Estimación de la carga mental de trabajo: método NASA TLX, en el cual se realizó análisis de medidas de tendencia central y se indagó relación a través de la prueba Chi cuadrado de Pearson, usando nivel de significación del 5%, con el programa SPSS 20. Resultados: La población predominante era de género masculino, donde la mayoría de los trabajadores fueron ingenieros pertenecientes al área de seguimiento y control, se evidenció asociación estadísticamente significativa entre la profesión con la percepción de exigencia física (p ≤ 0,001), de igual modo entre área de trabajo con la percepción de exigencia mental (p ≤ 0,001), en la cual se establece que la carga mental y el factor profesional (técnicos) y el factor laboral (área de seguimiento y control), son determinantes para la aparición de fatiga fisiológica y cognitiva, ya que en estos se evidencia mayor exigencia física en los trabajadores técnicos con un 81,40% y en los trabajadores del área de seguimiento y control con un 99,04%. Conclusión: Se encontró una alta exigencia mental, temporal y esfuerzo en los trabajadores y una relación significativa entre la profesión con la percepción de exigencia física, predominando en los técnicos, seguidos de abogados e ingenieros y entre el área de trabajo con la percepción de exigencia mental, siendo mayor en el área de seguimiento y control.

Prevalencia de los factores de riesgo psicosocial presentes en la población trabajadora de una entidad de salud de segundo nivel en el año 2013

Introducción: Los factores de riesgo psicosocial surgen a partir de una interacción dinámica de las cualidades humanas con el medio ambiente de trabajo, es decir, todas aquellas habilidades, necesidades, expectativas y costumbres de los trabajadores. En efecto, estas interacciones entre las condiciones del medio ambiente laboral y los factores humanos del trabajador, cuando son manejadas de manera negativa, conducen a alteraciones emocionales, problemas de comportamiento y cambios bioquímicos y neurohormonales, que a su vez pueden producir riesgos adicionales de enfermedades mentales y físicas. Objetivo: Determinar las prevalencias de los factores de riesgo psicosocial presentes en la población trabajadora de una entidad de salud de segundo nivel en el año 2013. Metodología: Se llevó a cabo un estudio de corte transversal, utilizando fuentes de datos secundarios de una Empresa de Salud del Estado de nivel II, donde se aplicó el instrumento de la batería de riesgo psicosocial, diseñada por el Ministerio de la Protección Social en asocio con la Pontificia Universidad Javeriana. Durante este período el hospital contaba con la gestión de 155 empleados, de los cuales 54 desempeñaban labores administrativas y 101 prestaban servicios asistenciales. La participación por género se distribuyó así: 104 mujeres y 51 hombres. La prevalencia de los factores de riesgo psicosocial se estimó por medio de los baremos establecidos por el Ministerio de la Protección Social para identificar el nivel de riesgo, los resultados fueron analizados desde estadísticas descriptivas y la aplicación de pruebas estadísticas en la comparación de los puntajes transformados de los dominios y dimensiones de los cuestionarios intra y extralaboral, según las características sociodemográficas y ocupacionales. Resultados: Se identificó una mayor proporción de personas con riesgo psicosocial intralaboral (45,8% riesgo muy alto), mientras que en la evaluación de los factores de riesgo extralaboral el comportamiento fue totalmente opuesto (78.1% sin riesgo), se pudo establecer que una mayor proporción de mujeres ejerce la profesión de la enfermería (71,3% asistencial) y la modalidad de contratación prevalente reportada fue a través de una cooperativa de trabajo asociado (82,2% asistenciales). Se determinó que existen diferencias en la percepción de los factores psicosociales tanto intra como extralaborales en los grupos con diferentes características sociodemográficas y ocupacionales. Conclusión: La investigación evidenció el impacto negativo de los factores de riesgo intralaboral sobre los trabajadores de la E.S.E, condición que afectó la percepción de la vida laboral, la productividad y el nivel de satisfacción de los trabajadores, por lo que se destaca la pertinencia de implementar actividades de intervención y prevención a corto plazo en el marco de un programa de vigilancia epidemiológica.

Las prácticas de recursos humanos y su incidencia en el bienestar laboral de los empleados

El objetivo del presente trabajo es formular, mediante una profunda revisión documental, bibliográfica y empírica, una fundamentación teórica sobre si existe o no incidencia de las prácticas de recursos humanos sobre el bienestar laboral de los empleados, y el que grado en que esta se presenta sobre aspecto como el engagement y la satisfacción laboral. Se realizó la revisión de múltiples estudios empíricos que aportaran evidencia sobre la relación que se presenta entre las principales prácticas de recursos humanos – provisión de personal, formación y desarrollo, promoción de personal, evaluación de desempeño, compensación y pago, y balance trabajo-familia – y el bienestar laboral, representado en el engagement y satisfacción en el trabajo de los empleados. Los resultados de este trabajo indican la existencia de una relación e incidencia de las prácticas de recursos humanos, el bienestar laboral, el engagement y la satisfacción laboral. De igual forma se encontró que estas relaciones son principalmente de carácter positivo, lo cual indica que las organizaciones que desarrollan este tipo de prácticas en su interior, fomentan tanto el desarrollo y la presencia de bienestar laboral en sus empleados, como su perdurabilidad.

Preditores da satisfação no trabalho dos professores do ensino básico e secundário português : remuneração, valores de trabalho e stress

O papel do professor é crucial numa sociedade, e o sucesso da sua missão depende da sua satisfação no trabalho. Este estudo tem como objectivo avaliar a satisfação no trabalho dos professores do ensino público português não superior. Uma amostra de 637 professores respondeu a um questionário online sobre satisfação no trabalho, valores de trabalho, e stress. Verificou-se que os professores, em média, se encontram insatisfeitos com o seu trabalho; que os do sexo masculino se encontram mais insatisfeitos que os do sexo feminino; que a variação da remuneração dentro da profissão não tem impacto sobre a satisfação no trabalho nos professores; que o stress é o principal preditor da satisfação, tendo um claro impacto negativo; e que tanto os valores intrínsecos de locus de controlo interno como os valores sociais influenciam (positivamente) a satisfação de modo independente.

Effects of host plant drought stress on the performance of the bird cherry-oat aphid, Rhopalosiphum padi (L.): a mechanistic analysis

1. The growth (increase in height and leaf number) of four grass species was reduced by a -0.5 MPa drought stress, but the performance of an associated herbivore, Rhopalosiphum padi (L.), was not affected consistently. The intrinsic rate of increase of R. padi was reduced by drought stress on three grass species, including Dactylis glomerata (L.), but was unaffected on Arrhenatherum elatius (L.). Therefore, there is no general relationship in the effect of plant drought on an insect herbivore, even among closely related host plant species. 2. Drought stress increased the quality of plant phloem sap, as indicated by increased sieve element osmotic pressure and essential amino acid concentrations. Thus, diet quality could not account for the reduced performance of R. padi under drought stress. The concentration of essential amino acids in the phloem of well-watered A. elatius was, however, lower than that of well-watered D. glomerata, correlating with the decreased performance of aphids on well-watered A. elatius. 3. There were no differences in aphid feeding duration between watering treatments or plant species but sap ingestion rates were reduced significantly under drought stress. 4. Using the measure of dietary amino acid concentrations and the estimate of sap ingestion, the essential amino acid flux through aphids was calculated. Compared with the flux through aphids feeding on well-watered D. glomerata, there was a reduction in aphids feeding on drought-stressed D. glomerata and drought-stressed A. elatius due to lower sap ingestion rates. The flux through aphids on well-watered A. elatius was also reduced due to low phloem essential amino acid concentrations. Thus, the performance of an aphid is correlated with the availability and accessibility of essential amino acids.

Heat shock protein 27 is the major differentially phosphorylated protein involved in renal epithelial cellular stress response and controls focal adhesion organization and apoptosis

We used two-dimensional difference gel electrophoresis to determine early changes in the stress-response pathways that precede focal adhesion disorganization linked to the onset of apoptosis of renal epithelial cells. Treatment of LLC-PK1 cells with the model nephrotoxicant 1,2-(dichlorovinyl)-L-cysteine (DCVC) resulted in a >1.5-fold up- and down-regulation of 14 and 9 proteins, respectively, preceding the onset of apoptosis. Proteins included those involved in metabolism, i.e. aconitase and pyruvate dehydrogenase, and those related to stress responses and cytoskeletal reorganization, i.e. cofilin, Hsp27, and alpha-b-crystallin. The most prominent changes were found for Hsp27, which was related to a pI shift in association with an altered phosphorylation status of serine residue 82. Although both p38 and JNK were activated by DCVC, only inhibition of p38 with SB203580 reduced Hsp27 phosphorylation, which was associated with accelerated reorganization of focal adhesions, cell detachment, and apoptosis. In contrast, inhibition of JNK with SP600125 maintained cell adhesion as well as protection against apoptosis. Active JNK co-localized at focal adhesions after DCVC treatment in a FAK-dependent manner. Inhibition of active JNK localization at focal adhesions did not prevent DCVC-induced phosphorylation of Hsp27. Overexpression of a phosphorylation-defective mutant Hsp27 acted as a dominant negative and accelerated the DCVC-induced changes in the focal adhesions as well as the onset of apoptosis. Our data fit a model whereby early p38 activation results in a rapid phosphorylation of Hsp27, a requirement for proper maintenance of cell adhesion, thus suppressing renal epithelial cell apoptosis.

Stress-induced changes in the Schizosaccharomyces pombe proteome using two-dimensional difference gel electrophoresis, mass spectrometry and a novel integrated robotics platform

Robotic and manual methods have been used to obtain identification of significantly changing proteins regulated when Schizosaccharomyces pombe is exposed to oxidative stress. Differently treated S. pombe cells were lysed, labelled with CyDye and analysed by two-dimensional difference gel electrophoresis. Gel images analysed off-line, using the DeCyder image analysis software [GE Healthcare, Amersham, UK] allowed selection of significantly regulated proteins. Proteins displaying differential expression were excised robotically for manual digestion and identified by matrix-assisted laser desorption/ionisation - mass spectrometry (MALDI-MS). Additionally the same set of proteins displaying differential expression were automatically cut and digested using a prototype robotic platform. Automated MALDI-MS, peak label assignment and database searching were utilised to identify as many proteins as possible. The results achieved by the robotic system were compared to manual methods. The identification of all significantly altered proteins provides an annotated peroxide stress-related proteome that can be used as a base resource against which other stress-induced proteomic changes can be compared.

Hydroponic isotope labelling of entire plants (HILEP) for quantitative plant proteomics; an oxidative stress case study

Hydroponic isotope labelling of entire plants (HILEP) is a cost-effective method enabling metabolic labelling of whole and mature plants with a stable isotope such as N-15. By utilising hydroponic media that contain N-15 inorganic salts as the sole nitrogen source, near to 100% N-15-labelling of proteins can be achieved. In this study, it is shown that HILEP, in combination with mass spectrometry, is suitable for relative protein quantitation of seven week-old Arabidopsis plants submitted to oxidative stress. Protein extracts from pooled N-14- and N-15-hydroponically grown plants were fractionated by SDS-PAGE, digested and analysed by liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS). Proteins were identified and the spectra of N-14/N-15 peptide pairs were extracted using their m/z chromatographic retention time, isotopic distributions, and the m/z difference between the N-14 and N-15 peptides. Relative amounts were calculated as the ratio of the sum of the peak areas of the two distinct N-14 and N-15 peptide isotope envelopes. Using Mascot and the open source trans-proteomic pipeline (TPP), the data processing was automated for global proteome quantitation down to the isoform level by extracting isoform specific peptides. With this combination of metabolic labelling and mass spectrometry it was possible to show differential protein expression in the apoplast of plants submitted to oxidative stress. Moreover, it was possible to discriminate between differentially expressed isoforms belonging to the same protein family, such as isoforms of xylanases and pathogen-related glucanases (PR 2). (C) 2008 Elsevier Ltd. All rights reserved.

Heat shock protein 27 is the major differentially phosphorylated protein involved in renal epithelial cellular stress response and controls focal adhesion organization and apoptosis

We used two-dimensional difference gel electrophoresis to determine early changes in the stress-response pathways that precede focal adhesion disorganization linked to the onset of apoptosis of renal epithelial cells. Treatment of LLC-PK1 cells with the model nephrotoxicant 1,2-(dichlorovinyl)-L-cysteine ( DCVC) resulted in a > 1.5-fold up- and down-regulation of 14 and 9 proteins, respectively, preceding the onset of apoptosis. Proteins included those involved in metabolism, i.e. aconitase and pyruvate dehydrogenase, and those related to stress responses and cytoskeletal reorganization, i.e. cofilin, Hsp27, and alpha-b-crystallin. The most prominent changes were found for Hsp27, which was related to a pI shift in association with an altered phosphorylation status of serine residue 82. Although both p38 and JNK were activated by DCVC, only inhibition of p38 with SB203580 reduced Hsp27 phosphorylation, which was associated with accelerated reorganization of focal adhesions, cell detachment, and apoptosis. In contrast, inhibition of JNK with SP600125 maintained cell adhesion as well as protection against apoptosis. Active JNK co-localized at focal adhesions after DCVC treatment in a FAK-dependent manner. Inhibition of active JNK localization at focal adhesions did not prevent DCVC-induced phosphorylation of Hsp27. Overexpression of a phosphorylation-defective mutant Hsp27 acted as a dominant negative and accelerated the DCVC-induced changes in the focal adhesions as well as the onset of apoptosis. Our data fit a model whereby early p38 activation results in a rapid phosphorylation of Hsp27, a requirement for proper maintenance of cell adhesion, thus suppressing renal epithelial cell apoptosis.

Free radicals, metals and antioxidants in oxidative stress-induced cancer

Oxygen-free radicals, more generally known as reactive oxygen species (ROS) along with reactive nitrogen species (RNS) are well recognised for playing a dual role as both deleterious and beneficial species. The "two-faced" character of ROS is substantiated by growing body of evidence that ROS within cells act as secondary messengers in intracellular signalling cascades, which induce and maintain the oncogenic phenotype of cancer cells, however, ROS can also induce cellular senescence and apoptosis and can therefore function as anti-tumourigenic species. The cumulative production of ROS/RNS through either endogenous or exogenous insults is termed oxidative stress and is common for many types of cancer cell that are linked with altered redox regulation of cellular signalling pathways. Oxidative stress induces a cellular redox imbalance which has been found to be present in various cancer cells compared with normal cells; the redox imbalance thus may be related to oncogenic stimulation. DNA mutation is a critical step in carcinogenesis and elevated levels of oxidative DNA lesions (8-OH-G) have been noted in various tumours, strongly implicating such damage in the etiology of cancer. It appears that the DNA damage is predominantly linked with the initiation process. This review examines the evidence for involvement of the oxidative stress in the carcinogenesis process. Attention is focused on structural, chemical and biochemical aspects of free radicals, the endogenous and exogenous sources of their generation, the metal (iron, copper, chromium, cobalt, vanadium, cadmium, arsenic, nickel)-mediated formation of free radicals (e.g. Fenton chemistry), the DNA damage (both mitochondrial and nuclear), the damage to lipids and proteins by free radicals, the phenomenon of oxidative stress, cancer and the redox environment of a cell, the mechanisms of carcinogenesis and the role of signalling cascades by ROS; in particular. ROS activation of AP-1 (activator protein) and NF-kappa B (nuclear factor kappa B) signal transduction pathways, which, in turn lead to the transcription of genes involved in cell growth regulatory pathways. The role of enzymatic (superoxide dismutase (Cu. Zn-SOD. Mn-SOD), catalase, glutathione peroxidase) and non-enzymatic antioxidants (Vitamin C, Vitamin E, carotenoids, thiol antioxidants (glutathione, thioredoxin and lipoic acid), flavonoids, selenium and others) in the process of careinogenesis as well as the antioxidant interactions with various regulatory factors, including Ref-1, NF-kappa B, AP-1 are also reviewed. 2006 Elsevier Ireland Ltd. All rights reserved.

Stress-induced changes in the Schizosaccharomyces pombe proteome using two-dimensional difference gel electrophoresis, mass spectrometry and a novel integrated robotics platform

Robotic and manual methods have been used to obtain identification of significantly changing proteins regulated when Schizosaccharomyces pombe is exposed to oxidative stress. Differently treated S. pombe cells were lysed, labelled with CyDye (TM) and analysed by two-dimensional difference gel. electrophoresis. Gel images analysed off-line, using the DeCyder (TM) image analysis software [GE Healthcare, Amersham, UK] allowed selection of significantly regulated proteins. Proteins displaying differential expression were excised robotically for manual digestion and identified by matrix-assisted laser desorption/ionisation - mass spectrometry (MALDI-MS). Additionally the same set of proteins displaying differential expression were automatically cut and digested using a prototype robotic platform. Automated MALDI-MS, peak label assignment and database searching were utilised to identify as many proteins as possible. The results achieved by the robotic system were compared to manual methods. The identification of all significantly altered proteins provides an annotated peroxide stress-related proteome that can be used as a base resource against which other stress-induced proteomic changes can be compared.

Stress relaxation behaviour of frozen sucrose solutions

The stress relaxation behaviour of two frozen sucrose solutions (7% and 19%) during indentation in the temperature range of -20C to -40C were investigated. The stress relaxation is similar to that of pure polycrystalline ice, which is controlled by steady-state creep. The steady state creep rate exponent, m, of 7% and 19% sucrose solutions lies between 2.3 and 3.6. The steady state creep rate constant, B, of 19% sucrose solution is greater than that of 7% sucrose solution. It is suggested that the steady-state creep rate exponent m depends on contributions from the proportions of favourably oriented grains, unfavourably oriented grains and grain boundaries to creep and that these components depend on the value of internal stress which is related to the hardness of samples at the different testing temperatures. The steady-state creep rate constant B depends on the mobility of dislocations in sucrose solutions which, in turn, depends on the temperature and the concentration of sucrose.

Stress relaxation behavior of wheat dough, gluten, and gluten protein fractions

Relaxation behavior was measured for dough, gluten and gluten protein fractions obtained from the U.K. biscuitmaking flour, Riband, and the U.K. breadmaking flour, Hereward. The relaxation spectrum, in which relaxation times (tau) are related to polymer molecular size, for dough showed a broad molecular size distribution, with two relaxation processes: a major peak at short times and a second peak at times longer than 10 sec, which is thought to correspond to network structure, and which may be attributed to entanglements and physical cross-links of polymers. Relaxation spectra of glutens were similar to those for the corresponding doughs from both flours. Hereward gluten clearly showed a much more pronounced second peak in relaxation spectrum and higher relaxation modulus than Riband gluten at the same water content. In the gluten protein fractions, gliadin and acetic acid soluble glutenin only showed the first relaxation process, but gel protein clearly showed both the first and second relaxation processes. The results show that the relaxation properties of dough depend on its gluten protein and that gel protein is responsible for the network structure for dough and gluten.