Attitudes among working professionals toward immigrants and refugees living in Ecuador: Impacts on health and well-being.

OBJECTIVE: To explore attitudes toward immigrants and refugees living in Ecuador. DESIGN AND MEASURES: A transnationalism framework informed this qualitative study, which utilized a semi-structured interview guide to elicit responses from participants about their attitudes toward immigrants and refugees. Interviews were conducted in Spanish, audio-taped, transcribed, coded, and analyzed in Spanish to identify emergent themes. Demographic data were analyzed using SPSS. SAMPLE: Participants (n = 50) were recruited from five sectors that interact with refugees: health care, the press, the police, nongovernmental organizations, and education. Fifty interviews were conducted with adults in Quito, Ecuador, in 2017. RESULTS: Participants reported concerns about the health and well-being of immigrants and refugees, expressed a willingness to assist them, but within limits, noted discrimination and bias against refugees, and cited social policies and human rights as factors that influenced their attitudes. CONCLUSIONS: Our findings indicate that immigrants and refugees face challenges which impact their health and well-being, according to participants in the study. Social policies can influence attitudes, but are also affected by rapidly shifting immigration patterns. Migration flows in South America is an under-studied area of research, with opportunity for further public health nursing inquiry.

Superoxide dismutase 1 (SOD1) is essential for H2O2-mediated oxidation and inactivation of phosphatases in growth factor signaling.

Superoxide dismutase 1 (SOD1) is an abundant copper/zinc enzyme found in the cytoplasm that converts superoxide into hydrogen peroxide and molecular oxygen. Tetrathiomolybdate (ATN-224) has been recently identified as an inhibitor of SOD1 that attenuates FGF-2- and VEGF-mediated phosphorylation of ERK1/2 in endothelial cells. However, the mechanism for this inhibition was not elucidated. Growth factor (GF) signaling elicits an increase in reactive oxygen species (ROS), which inactivates protein tyrosine phosphatases (PTP) by oxidizing an essential cysteine residue in the active site. ATN-224-mediated inhibition of SOD1 in tumor and endothelial cells prevents the formation of sufficiently high levels of H(2)O(2), resulting in the protection of PTPs from H(2)O(2)-mediated oxidation. This, in turn, leads to the inhibition of EGF-, IGF-1-, and FGF-2-mediated phosphorylation of ERK1/2. Pretreatment with exogenous H(2)O(2) or with the phosphatase inhibitor vanadate abrogates the inhibition of ERK1/2 phosphorylation induced by ATN-224 or SOD1 siRNA treatments. Furthermore, ATN-224-mediated SOD1 inhibition causes the down-regulation of the PDGF receptor. SOD1 inhibition also increases the steady-state levels of superoxide, which induces protein oxidation in A431 cells but, surprisingly, does not oxidize phosphatases. Thus, SOD1 inhibition in A431 tumor cells results in both prooxidant effects caused by the increase in the levels of superoxide and antioxidant effects caused by lowering the levels of H(2)O(2). These results identify SOD1 as a master regulator of GF signaling and as a therapeutic target for the inhibition of angiogenesis and tumor growth.

A MET Targeting Antibody-Drug Conjugate Overcomes Gemcitabine Resistance in Pancreatic Cancer.

PURPOSE: Pancreatic cancer is an aggressive disease associated with a poor 5-year overall survival. Most patients are ineligible for surgery due to late diagnosis and are treated primarily with chemotherapy with very limited success. Pancreatic cancer is relatively insensitive to chemotherapy due to multiple factors, including reduced bioavailability of drugs to tumor cells. One strategy to improve drug efficacy with reduced toxicity is the development of antibody-drug conjugates (ADC), which have now been used successfully to treat both solid and liquid tumors. Here, we evaluate the efficacy of TR1801-ADC, a newly developed ADC composed of a MET antibody conjugated to the highly potent pyrrolobenzodiazepine toxin-linker, tesirine. EXPERIMENTAL DESIGN: We first evaluated MET expression and subcellular localization in pancreatic cancer cell lines, human tumors, and patient-derived xenografts (PDX). We then tested TR1801-ADC efficacy in vitro in pancreatic cancer cell lines. Preclinical evaluation of TR1801-ADC efficacy was conducted on PDXs selected on the basis of their MET expression level. RESULTS: We show that MET is highly expressed and located at the plasma membrane of pancreatic cancer cells. We found that TR1801-ADC induces a specific cytotoxicity in pancreatic cancer cell lines and a profound tumor growth inhibition, even in a gemcitabine-resistant tumor. We also noted synergism between TR1801-ADC and gemcitabine in vitro and an improved response to the combination in vivo. CONCLUSIONS: Together, these results suggest the promise of agents such as TR1801-ADC as a novel approach to the treatment of pancreatic cancer.

TR1801-ADC: a highly potent cMet antibody-drug conjugate with high activity in patient-derived xenograft models of solid tumors.

cMet is a well-characterized oncogene that is the target of many drugs including small molecule and biologic pathway inhibitors, and, more recently, antibody-drug conjugates (ADCs). However, the clinical benefit from cMet-targeted therapy has been limited. We developed a novel cMet-targeted 'third-generation' ADC, TR1801-ADC, that was optimized at different levels including specificity, stability, toxin-linker, conjugation site, and in vivo efficacy. Our nonagonistic cMet antibody was site-specifically conjugated to the pyrrolobenzodiazepine (PBD) toxin-linker tesirine and has picomolar activity in cancer cell lines derived from different solid tumors including lung, colorectal, and gastric cancers. The potency of our cMet ADC is independent of MET gene copy number, and its antitumor activity was high not only in high cMet-expressing cell lines but also in medium-to-low cMet cell lines (40 000-90 000 cMet/cell) in which a cMet ADC with tubulin inhibitor payload was considerably less potent. In vivo xenografts with low-medium cMet expression were also very responsive to TR1801-ADC at a single dose, while a cMet ADC using a tubulin inhibitor showed a substantially reduced efficacy. Furthermore, TR1801-ADC had excellent efficacy with significant antitumor activity in 90% of tested patient-derived xenograft models of gastric, colorectal, and head and neck cancers: 7 of 10 gastric models, 4 of 10 colorectal cancer models, and 3 of 10 head and neck cancer models showed complete tumor regression after a single-dose administration. Altogether, TR1801-ADC is a new generation cMet ADC with best-in-class preclinical efficacy and good tolerability in rats.

Copper binding by tetrathiomolybdate attenuates angiogenesis and tumor cell proliferation through the inhibition of superoxide dismutase 1.

PURPOSE: A second-generation tetrathiomolybdate analogue (ATN-224; choline tetrathiomolybdate), which selectively binds copper with high affinity, is currently completing two phase I clinical trials in patients with advanced solid and advanced hematologic malignancies. However, there is very little information about the mechanism of action of ATN-224 at the molecular level. EXPERIMENTAL DESIGN: The effects of ATN-224 on endothelial and tumor cell growth were evaluated in cell culture experiments in vitro. The antiangiogenic activity of ATN-224 was investigated using the Matrigel plug model of angiogenesis. RESULTS: ATN-224 inhibits superoxide dismutase 1 (SOD1) in tumor and endothelial cells. The inhibition of SOD1 leads to inhibition of endothelial cell proliferation in vitro and attenuation of angiogenesis in vivo. The inhibition of SOD1 activity in endothelial cells is dose and time dependent and leads to an increase in the steady-state levels of superoxide anions, resulting in the inhibition of extracellular signal-regulated kinase phosphorylation without apparent induction of apoptosis. In contrast, the inhibition of SOD1 in tumor cells leads to the induction of apoptosis. The effects of ATN-224 on endothelial and tumor cells could be substantially reversed using Mn(III)tetrakis(4-benzoic acid)porphyrin chloride, a catalytic small-molecule SOD mimetic. CONCLUSIONS: These data provide a distinct molecular target for the activity of ATN-224 and provide validation for SOD1 as a target for the inhibition of angiogenesis and tumor growth.

Decline of General Intelligence in Children Exposed to Manganese from Mining Contamination in Puyango River Basin, Southern Ecuador.

Based on ecosystem approaches to health (Ecohealth), this study sought to identify neurobehavioral disorders in children exposed to several levels of toxic metal pollution from gold mining in the Puyango River Basin, Southern Ecuador. Ninety-three children born or living in the study area participated in the study. A neurobehavioral test battery consisting of 12 tests assessing various functions of the nervous system was applied as well as a questionnaire regarding events of exposure of children's mothers to contaminants during perinatal period. Hair samples were taken from children to determine manganese concentrations. Descriptive and inferential statistics were applied in order to examine possible relationships between exposure events, hair manganese, and neurobehavioral disorders. Having controlled co-variables such as age and educational level, it was found that children with elevated levels of hair manganese (over 2 µg/g) had poor performance in the test of general intelligence (Raven's Progressive Color Matrices Scale PCM). The Ecohealth approach helped to identify that children in the lower Puyango Basin with very elevated levels of manganese in the river water (970 µg/L) are the ones who have the highest levels of hair manganese and the worst performance in the intelligence test.

Sending-country violence and receiving-country discrimination: effects on the health of Colombian refugees in Ecuador.

This study explored factors affecting the health and well being of recent refugees from Colombia in Ecuador. Data collection focused on how sending-country violence and structural violence in a new environment affect immigrant health vulnerability and risk behaviors. A qualitative approach included ethnographic observation, media content analysis, focus groups, and individual interviews with refugees (N = 137). The focus groups (5) provided perspectives on the research domains by sex workers; drug users; male and female refugees; and service providers. Social and economic marginalization are impacting the health and well being of this growing refugee population. Data illustrate how stigma and discrimination affect food and housing security, employment and health services, and shape vulnerabilities and health risks in a new receiving environment. Widespread discrimination in Ecuador reflects fears, misunderstanding, and stereotypes about Colombian refugees. For this displaced population, the sequelae of violence, combined with survival needs and lack of support and protections, shape new risks to health and well-being.

Long-range effect of cyanide on mercury methylation in a gold mining area in southern Ecuador.

Small-scale gold mining in Portovelo-Zaruma, Southern Equador, performed by mercury amalgamation and cyanidation, yields 9-10 t of gold/annum, resulting in annual releases of around 0.65 t of inorganic mercury and 6000 t of sodium cyanide in the local river system. The release of sediments, cyanide, mercury, and other metals present in the ore such as lead, manganese and arsenic significantly reduces biodiversity downstream the processing plants and enriches metals in bottom sediments and biota. However, methylmercury concentrations in sediments downstream the mining area were recently found to be one order of magnitude lower than upstream or in small tributaries. In this study we investigated cyanide, bacterial activity in water and sediment and mercury methylation potentials in sediments along the Puyango river watershed, measured respectively by in-situ spectrophotometry and incubation with (3)H-leucine and (203)Hg(2+). Free cyanide was undetectable (<1 µg·L(-1)) upstream mining activities, reached 280 µg·L(-1) a few km downstream the processing plants area and was still detectable about 100 km downstream. At stations with detectable free cyanide in unfiltered water, 50% of it was dissolved and 50% associated to suspended particles. Bacterial activity and mercury methylation in sediment showed a similar spatial pattern, inverse to the one found for free cyanide in water, i.e. with significant values in pristine upstream sampling points (respectively 6.4 to 22 µgC·mg wet weight(-1)·h(-1) and 1.2 to 19% of total (203) Hg·gdry weight(-1)·day(-1)) and undetectable downstream the processing plants, returning to upstream values only in the most distant downstream stations. The data suggest that free cyanide oxidation was slower than would be expected from the high water turbulence, resulting in a long-range inhibition of bacterial activity and hence mercury methylation. The important mercury fluxes resultant from mining activities raise concerns about its biomethylation in coastal areas where many mangrove areas have been converted to shrimp farming.

Estandarización de un ensayo inmunoenzimático para la detección de anticuerpos anti-ADN doble cadena en el lupus eritematoso sistémico / Standardization of an immunoenzymatic assay to detect anti-double-stranded DNA antibodies in systemic lupus erythematosus

Introducción: los anticuerpos anti-ADN doble cadena son un marcador serológico diagnóstico de lupus eritematoso sistémico (LES). El ensayo inmunoenzimático en fase sólida es una técnica rápida y rentable para su detección. Objetivo: estandarizar un ELISA que detecte anti ADN doble cadena para el diagnóstico del lupus. Métodos: los pasos que se siguieron para la estandarización incluyeron la preparación de controles, la sensibilización de la fase sólida, la selección de los amortiguadores y conjugado del ensayo, la evaluación de las condiciones de reacción y la determinación del nivel de corte. Además se realizó el estudio de inespecificidades. Se probaron 5 tipos de placas de poliestireno y se compararon ADN plasmádico de E.coli, pUC19 y ADN genómico humano como antígenos de recubrimiento. Se evaluó el efecto de la poli-L-lisina y la irradiación de la placa con luz ultravioleta, en la fijación del antígeno. El valor de corte del ensayo se determinó por el método del valor límite. Resultados: se observó disociación del antígeno cuando no se utilizó poli-L-lisina en el pretratamiento de la placa y la irradiación con luz UV no favoreció la unión del ADN a la fase sólida. No se encontraron diferencias significativas (p=0,710) entre ambos ADN, en el recubrimiento. El valor de corte (K=3) permitió clasificar como positivas 28 muestras (63,6 porciento) de pacientes con LES. Conclusiones: el método estandarizado, con el empleo de ADN plasmádico, permitió la detección de anticuerpos anti-ADN doble cadena en pacientes con lupus

Introduction: anti-double-stranded DNA antibodies are a diagnostic serological marker for systemic lupus erythematosus (SLE). The solid-phase immunoenzymatic assay is a rapid, cost-effective technique for their detection. Objective: Standardize an ELISA detecting anti-double-stranded DNA for the diagnosis of lupus. Methods: the standardization process included the following steps: preparation of controls, sensitization of the solid phase, selection of buffers and assay conjugate, evaluation of reaction conditions and determination of the cut-off level. A study of unspecificities was also conducted. Five types of polystyrene plates were tested, and a comparison was made of E. coli (pUC19) plasmid DNA and human genomic DNA as coating antigens. An evaluation was conducted of the effect of poly (L-lysine) and irradiation of the plate with ultraviolet light upon antigen fixation. The assay cut-off value was determined by the limit value method. Results: antigen dissociation was observed when poly (L-lysine) was not used in the pretreatment of the plate and UV light irradiation did not foster DNA binding to the solid phase. No significant differences were found (p=0.710) between the two DNA coatings. The cut-off value (K=3) made it possible to classify 28 samples of patients with SLE as positive (63.6 percent). Conclusions: the method standardized with the use of plasmid DNA enabled detection of anti-double-stranded DNA antibodies in patients with lupus

Estabilidad de un suero control multienzimático utilizado como material de referencia en los laboratorios clínicos / Stability of a multienzyme control serum used as reference material in clinical laboratories

Una de las vías fundamentales para garantizar la calidad de los ensayos realizados en los laboratorios clínicos es mediante el uso de materiales de referencia. Una problemática a la que nos enfrentamos es la escasez de estos productos en el mercado nacional dado su alto costo. Objetivo: evaluar la estabilidad de un suero bovino adulto enriquecido con las enzimas alanina aminotransferasa (ALAT/TGP), aspartato aminotransferasa (ASAT/TGP), fosfatasa alcalina (FA) y amilasa. Métodos: se evaluó la estabilidad a tiempo real de la matriz enriquecida con las diferentes enzimas durante 12 meses a 2 temperaturas (refrigeración y congelación). Se evaluó el efecto del glicerol sobre la actividad enzimática de los extractos, así como el efecto de los preservantes propilenglicol y etilenglicol en la estabilidad de las enzimas. Resultados: los extractos enzimáticos obtenidos comenzaron a perder la actividad biológica a partir de los 15 días, independientemente de la temperatura de almacenamiento y de la presencia o no de glicerol. Los resultados del ensayo a tiempo real realizados a la matriz enriquecida, mostraron que la estabilidad varió con el tiempo y con el tipo de enzima, independientemente del preservante ensayado, disminuyendo por debajo de los límites aceptables de actividad enzimática luego de 3 meses de almacenamiento del producto a 4 ºC. Conclusiones: se logró un material de referencia multienzimático estable por un período de 3 meses

A fundamental method to assure the quality of clinical laboratory tests is the use of reference materials. A problem we are faced with is the scarcity of these products in the domestic market, due their high cost. Objective: Evaluate the stability of an adult bovine serum enriched with the enzymes alanine aminotransferase (ALT, GPT), aspartate aminotransferase (AST, GPT), alkaline phosphatase (AP) and amylase. Methods: This enzyme-enriched matrix underwent real-time stability assessment during 12 months at two temperatures (refrigerated and frozen). An evaluation was made of the effect of glycerol on the enzymatic activity of extracts, as well as the effect of the preservatives propylene glycol and ethylene glycol on enzymatic stability. Results: The enzyme extracts obtained began to lose their biological activity at 15 days, irrespective of the storage temperature and the presence or absence of glycerol. The real time assessment of the enriched matrix showed that stability varied with time and enzyme type, irrespective of the preservative tested, and fell below acceptable limits of enzymatic activity after three months of storage at 4 ºC. Conclusions: A multienzyme reference material was obtained which was stable for a period of 3 months

Purificación de ADN genómico humano para el diagnóstico del lupus eritematoso sistémico / Purification of human genomic DNA for the diagnosis of the systemic lupus erythematosus

Fundamento: La molécula de ADN constituye un antígeno necesario en el recubrimiento de un sistema inmunoenzimático destinado al diagnóstico de enfermedades autoinmunes, específicamente del lupus eritomatoso sistémico. Por otra parte, esta molécula se emplea en la obtención de anticuerpos monoclonales anti ADN de doble cadena. Objetivo: Se evaluó la calidad del ADN humano purificado por el método del fenol:cloroformo con fines diagnósticos. La molécula fue obtenida por primera vez en el Centro de Inmunología y Productos Biológicos de Camagüey. Método: El ADN se extrajo a partir de tejido prostático de un paciente con hiperplasia prostática benigna. Se realizó la técnica convencional de fenol: cloroformo/alcohol isoamilico. El tejido fue previamente tratado con Pronasa a 56ºC. La corrida electroforética se realizó en gel de agarosa 0,8 %, y se determinó la relación 260/280nm mediante espectrofotometría, con la finalidad de evaluar la integridad de la macromolécula, así como el grado de pureza de la misma respectivamente. Resultados: No se observó degradación de la molécula de ADN genómico humano, y la relación 260/280 fue de 1,6. La molécula de ADN humana fue ensayada en el recubrimiento de un ELISA destinado al diagnóstico del Lupus, y su comparación con ADN plásmidico no arrojó diferencias significativas (p= 0.710). Conclusiones: El método aquí descrito proporcionó una molécula de ácido nucleico con la calidad requerida para ser utilizada en el sistema inmunoenzimático destinado al diagnóstico del lupus eritematoso sistémico.

Background: The DNA molecule constitutes a necessary antigen in the capping of an immunoenzymatic system dedicated to the diagnosis of autoimmune diseases, specifically of the systemic lupus erythematosus. On the other hand, this molecule is used for obtaining the anti DNA monoclonal antibodies´ of double chain. Objective: The quality of the purified human DNA was evaluated by the phenol method: chloroform with diagnostic purposes. The molecule for the first time was obtained in the Center of Immunology and Biological Products of Camagüey. Method: The DNA was extracted from a patient's prostatic tissue with benign prostatic hyperplasia. The conventional technique of phenol: chloroform / isoamyl alcohol was perfomed. The tissue was previously treated with Pronasa at 56ºC. The agarose gel electrophoresis was performed at 0,8% and the relationship 260/280nm was determined by spectrophotometry, with the purpose of evaluating the integrity of the macromolecule, as well as its grade of purity respectively. Results: It was not observed degradation of the human genomic DNA molecule, and the relationship 260/280 was about 1,6. The human DNA molecule was tested in the capping of an ELISA dedicated to lupus diagnosis, and its comparison with plasmid DNA did not show significant differences (p = 0.710). Conclusions: The described method, provided a nucleic acid molecule with the quality required to be used in the immunoenzymatic system dedicated to the diagnosis of the systemic lupus erythematosus.

Caracterización electroforética y cromatográfica del veneno del alacrán Rhopalurus junceus / Electrophoretic and chromatographic characterization of the Rhopalurus junceus scorpion venom

El veneno del alacrán azul, Rhopalurus junceus es actualmente comercializado con el nombre de Escozul. Este producto natural se emplea en el tratamiento de diferentes patologías, sin embargo en la literatura revisada no aparece información referente a la caracterización bioquímica del extracto de este ejemplar cubano. Objetivo: hacer una caracterización bioquímica preliminar del veneno crudo del alacrán cubano mediante el empleo de dos técnicas destinadas a estos fines. Método: se empleó la electroforesis discontinua de proteínas en gel de poliacrilamida al 15% y la cromatografía de alta presión. Resultados: se identificó un patrón difuso correspondiente a péptidos de talla inferiores a catorce KDa, mientras que por HPLC se determinaron trece picos en el veneno crudo de esta especie. Conclusiones: el veneno del alacrán azul presenta una composición molecular similar a la descrita para otras especies con una mezcla molecular inferior a catorce KDa.

The blue scorpion venom, Rhopalurus junceus is currently marketed with the name of Escozul. This natural product is used in the treatment of different pathologies; however in the revised literature doesn't appear concerning information to the biochemical characterization of the extract of this Cuban specimen. Objective: to make a preliminary biochemical characterization on the crude venom of the Cuban scorpion by means of the employment of two techniques dedicated to these purposes. Method: the discontinuous electrophoresis of proteins was used in polyacrylamide to 15% and the chromatography of high pressure. Results: a diffuse pattern corresponding to inferior size peptides to fourteen KDa was identified, while for HPLC thirteen peaks were determined in the crude venom of this species. Conclusions: the blue scorpion venom presents a similar molecular composition to the one described for other species with an inferior molecular mixture to fourteen KDa.

Evaluación de la toxicidad in vitro del veneno del alacrán Rophalurus junceus a través de un ensayo celular / In vitro toxicity assessment caused by Rophalurus junceus scorpion poison though a cellular assay

El veneno del alacrán azul, Rophalurus junceus es comercializado con el nombre de Escozul. Este producto natural se emplea en el tratamiento de diferentes patologías. Este trabajo evaluó el efecto citotóxico in vitro de este producto en las líneas tumorales P3-X63/AG8/653 y Dunning R3327-G provenientes de mieloma murino y próstata de rata, respectivamente. La citotoxicidad fue evaluada mediante la cinética de crecimiento celular y el daño metabólico. Se utilizaron dosis de 1, 10, 20, 50, 100 y 200 mg/mL. El veneno presentó un efecto citostático dependiente de la línea tumoral en cuestión. Las dosis efectivas variaron entre las líneas celulares ensayadas. Se estudió además la estabilidad del producto almacenado durante 30 días a temperaturas de -20 y 4ºC, se evidenció la pérdida de la actividad biológica. El trabajo demostró la citotoxicidad del veneno crudo del alacrán azul en cultivos celulares.

Poison of blue scorpion (Rophalurus junceus) is marketed as Escozul. This natural product is used in treatment of different pathologies. Present paper evaluated the in vitro cytotoxic effect of this product in P3-X63/AG8/653 and Dunning R3327-G tumor lines from murine myeloma and rat prostate, respectively. Cytotoxic effect was evaluated by means of cellular growing kinetics and the metabolic damage. Doses of 1,10, 20, 50, 100, and 200 ìg/mL. Poison had a cytostatic effect dependent of tumor line at issue. Doses effective varied among the cellular lines assessed. We studied also stability of product stored during 30 days at temperatures of -20° and 4° C, evidenced the loss of biological activity. We showed cytotoxic effect of crude poison of blue scorpion in cellular cultures.

Cambio climático y salud en la región andina / Climate change and health in the andean region

Se presentan de manera resumida las causas fundamentales que contribuyen al calentamiento global y una serie de evidencias de la realidad que nos afecta: aumenta la temperatura de la tierra, se derriten los glaciares, sube el nivel de los océanos y se incrementa la frecuencia e intensidad de los eventos meteorológicos; todo ello como producto de la acumulación inusitada de gases de efecto invernadero, provenientes de la actividad humana. Se plantea las implicaciones que, de forma directa o indirecta, el cambio climático tiene para la salud, en particular para los países andinos: trastornos vinculados con la disponibilidad y calidad del agua y los alimentos, afecciones respiratorias, infecciones de transmisión vectorial, cáncer y enfermedades crónico degenerativas, cuadros asociados con desastres climáticos y temperaturas extremas. Finalmente, se revisa las propuestas y cursos de acción.

We present a short summary of the root causes that contribute to global warming and a host of evidence of the reality that affects us; such as: raising the temperature of the earth, melting glaciers, rising ocean level, increases the frequency and intensity of weather events, all as a result of the unusual accumulation of greenhouse gases, as product of human activity. There are implications that directly or indirectly, the climate change has to health in particular for Andean countries; such as: disorders linked to the availability and quality of water and food, respiratory disease, vector-borne infections, cancer and pathologies chronic degenerative tables associated with climatic disasters and extreme temperatures. Finally we review proposals and courses of action.

Purificación del antígeno específico prostático con alto grado de pureza mediante el método de electroelusión / Purification of prostatic specific antigen of high purity level through the electroelusión method

Se evaluó la utilidad de la técnica de electroelusión en la obtención del antígeno específico prostático con actividad biológica para su empleo en sistemas basados en el reconocimiento antígeno-anticuerpo (ELISA, RIA, SUMA). Para la muestra se partió del semen de pacientes voluntarios, precipitados con sulfato de amonio al 70 por ciento. Las corridas electroforéticas en geles de poliacrilamida no reducidos se llevaron a cabo a 4º C. Se procedió a electroeluir el fragmento de acrilamida cortado en la talla deseada (33 KDa) y para ello se utilizaron marcadores adecuados de peso molecular. La metodología empleada permitió obtener un antígeno con un grado de pureza próximo al 70 por ciento. El método de electroelusión constituye un procedimiento rápido y poco costoso para su uso en laboratorios con bajos recursos. Los resultados aquí obtenidos no mostraron diferencias significativas (p=0.181) con el PSA purificado por el método cromatográfico, lo que sugiere su uso en obtención del antígeno específico prostático y otras moléculas para tales fines

Cambios en la actividad biológica de un antígeno debido a la temperatura generada durante la electroforesis de poliacrilamida / Changes in the biological activity of an antigen due to the temperature generated during the polyacrylamide electrophoresis

Se evaluó el efecto que origina la temperatura sobre la actividad biológica de un antígeno durante la electroforesis en geles no reductores de poliacrilamida, porque en ocasiones la técnica precede a la electroelusión, método empleado en la purificación de determinadas proteínas. Se utilizó el antígeno específico prostático para el ensayo, este se purificó a partir del semen de pacientes voluntarios, precipitado con sulfato de amonio 70 por ciento. Las corridas (3 para cada temperatura), se llevaron a cabo a 4 y 25 °C, y se realizaron a 20 mA. Para cada temperatura ensayada, los fragmentos provenientes de los geles cortados a la talla esperada para el antígeno específico prostático (33 kDa), se electroeluyeron a 4 °C. Mediante la comparación de las concentraciones de proteínas empleando la técnica de Lowry y el método radioinmunoenzimático, se cuantificó la cantidad de proteína biológicamente activa posterior a la electroforesis. Se utilizó un antígeno específico prostático comercial como control. Los resultados indican que el antígeno a 4 °C, conserva 80 por ciento de su actividad biológica, lo que no sucede a 25 °C donde más de 50 por ciento de la proteína es biológicamente inactiva

Saphylococcus aureus y su identificación en los laboratorios microbiológicos: revisión bibliográfica / Staphylococcus aureus and its identification in microbiologic labs: bibliographical review

Se realizó un compendio con más de 30 publicaciones que abordan las nuevas investigaciones sobre los principales elementos que intervienen en el mecanismo de infección y los métodos diagnósticos más utilizados para la detección del Staphylococcus aureus por parte de los laboratorios microbiológicos en el mundo y Cuba. Nuevas moléculas que contribuyeron al proceso infectivo del ente se encuentran en fase de estudio, para algunas de ellas se describió su papel en el mecanismo. El método más difundido en nuestro país es el ensayo de la coagulasa en tubo. Se decidió informar los métodos más utilizados en el diagnóstico de esta entidad, incluyendo los más recientes, aún en fase de estudio y estandarización en algunos casos, así como brindar algunos de los elementos básicos o factores que intervienen en el mecanismo de infección

Plasma equino como sustituto del plasma humano en la identificación del staphylococcus aureus en los laboratorios de microbiología / Equine plasma as a substitute of human plasma in the identification of staphylococcus aureus in microbiology laboratories

Se evaluaron varios plasmas de diferentes especies y se trabajó un total de 106 cepas, por los problemas éticos que impone este plasma, así como la baja sensibilidad en la identificación de cepas de Staphylococcus aureus. Esta se realiza en los laboratorios microbiológicos de la red hospitalaria nacional con plasma de origen humano. Se estudió el efecto de la dilución, del tiempo de incubación, así como la influencia del sexo en la identificación de las cepas positivas (índice de positividad). Se determinaron las condiciones óptimas de trabajo, las cuales no difirieron significativamente de los resultados obtenidos con el plasma de conejo. El plasma humano mostró ser poco efectivo en la identificación de cepas positivas (57,5 por ciento), revelando diferencias significativas con el plasma de conejo y del equino (95,3 y 94,3 por ciento, respectivamente). Los resultados aquí obtenidos sugieren la sustitución del plasma humano por el plasma equino en los laboratorios microbiológicos para la identificación de este microorganismo patógeno. Este plasma mostró ser estable a - 20 ºC por un período de 12 meses

Reflexiones para la investigación de la salud de los trabajadores / Reflections for the health research in workers

Este artículo plantea una reflexión sobre la investigación epidemiológica en salud de los trabajadores y custiona los enfoques convencionales que no permiten un abordaje integral de los problemas de la salud en el trabajo. Se ubica el papel de la salud ocupacional en la política del estado y se analiza el caracter conflictivo y contradictorio de la salud ocupacional debido a su capacidad para revelar el potencial carácter patogénico del trabajo. Se analiza la categoría trabajo y su influencia sobre la salud y la enfermedad de los pueblos, sus limitaciones explicativas y se critican los presupuestos teóricos de la salud ocupacional tradicional. Finaliza con propuestas alternativas que enfatizan la necesidad de desarrollar nuevas categorías de análisis y para impulsar activamente la participación de los trabajadores

Las Nuevas propuestas metodológicas: el debate de lo cualitativo y cuantitativo / A news methodology proposal: qualitative and quantitative debate

Con la expansión del modelo neoliberal, América Latina ha experimentado cambios, cuyas expresiones concretas en las condiciones de trabajo y en la salud de los grupos laborales, es la desmejora notable; lo cual exige de los investigadores en salud de los trabajadores, estudios que permitan formas de intervención que den respuestas a las necesidades más sentidas de los grupos mayoritarios. En esa perspectiva, han surgido formas alternativas de análisis cualitativos como el modelo obrero italiano y la introducción de nuevas categorias como "enfermedades relacionadas con el trabajo", "cargas psíquicas y mentales". A esas propuestas se agrega la triangulación metodológica que permite la utilización de varias técnicas que se complementan para abordar en forma crítica la realidad ubicada en el tiempo y en el espacio