Effects of 2-Deoxy-D-Glucose on In Vitro Cat Carotid Body

Producción CientíficaThe process of chemosensory transduction in the arterial chemoreceptors is not well understood. According to the metabolic hypothesis of chemoreception, a decrease in arterial pO 2 will produce a decrease in the adenosine triphosphate (ATP) content in the chcmosensory type I cells, leading to release of a neurotransmitter and increased sensory neural activity. There is a paucity of direct experimental support for this hypothesis, and in the present work, we have tested the postulates of the metabolic hypothesis in an in vitro preparation of cat carotid body using 2-deoxy-D-glucose as an ATP-depleting agent. This preparation, when superfused with Tyrode containing 5 mM Na+-pyruvate instead of glucose, responds normally to hypoxia, low pH and acetylcholinc, and maintains normal ATP levels. Under these conditions, 2-deoxy-D-glucose is a chemostimulant, i.e. electrical activity in the carotid sinus nerve is increased, with a threshold concentration of 0.25 mM and a maximum response at about 2-4 raM. These concentrations of 2-deoxyglucose evoke a dose-dependent release of [3H]dopamine (synthesized from pH]tyrosine) from the carotid bodies which parallels the electrical activity. The 2-deoxy-D-glucose-evoked release and electrical activity is dependent on the presence of extracellular Ca 2+ . These same concentrations of 2-deoxy-D-glucose significantly reduce the ATP content of the carotid bodies. The events postulated bv the metabolic hypothesis, i.e. decrease in ATP content, release of a putative neurotransminer and activation of the sensory nerve endings are found to occur simultaneously. A possible cause-effect relationship between these three events is discussed

La formación en España de médicos especialistas en Medicina Preventiva y Salud Pública

Producción CientíficaEl modelo moderno de formación médica especializada en España se definió en 19841 y se basa en el programa de Médicos Internos Residentes (MIR). En 1999 se produjo el acceso al título de especialista de buena parte de la gran bolsa de médicos que trabajaban en el sector sin tener título oficial de especialista (denominados médicos especialistas sin título oficial (MESTOS) mediante una convocatoria excepcional del Consejo Nacional de Especialidades Médicas2. Desde entonces, la oferta de formación mediante la convocatoria MIR es el esquema predominante, aunque persiste la vía excepcional y sea factible la homologación de títulos de especialista obtenidos en el extranjero. Este modelo se ha perfeccionado en los últimos tiempos3, destacando la aprobación en 2005 del programa de la especialidad de Medicina Preventiva y Salud Pública(MPySP)4,5, y avanzando en una mayor definición del funcionamiento de las unidades docentes, de las comisiones de docencia, y de los tutores6,7. Al redactar este documento nos proponemos proporcionar algunos elementos de información sobre la oferta de formación médica especializada en MPySP. La información descriptiva se ha extraído de las últimas convocatorias publicadas en el Boletín Oficial del Estado (BOE), correspondientes al periodo 2007-10. El esbozo de elementos para la evaluación procede de reflexiones compartidas por los miembros de la Comisión Nacional de la Especialidad (CNE) a lo largo del período 2010-11, los cuales son especialistas. Independientemente de que puedan darse progresos en la sistematización de la formación especializada de otras profesiones implicadas en la salud pública, algo muy deseable8, nos concentramos aquí en la situación de esta especialidad médic

Correlation Between Adenosine Triphosphate Levels, Dopamine Release and Electrical Activity in the Carotid Body: Support for the Metabolic Hypothesis of Chemoreception

Producción CientíficaAn unsolved issue for the arterial chemoreceptors is the mechanism by which hypoxia and other natural stimuli lead to an increase of activity in the carotid sinus nerve. According to the 'metabolic hypothesis', the hypoxic activation of the carotid body (CB) is mediated by a decrease of the ATP levels in the type I cells, which then release a neurotransmitter capable of exciting the sensory nerve endings. Using an in vitro preparation of cat CB, we report that ATP levels in the CB do in fact decrease when the organs are exposed to moderate, short lasting hypoxia (5 min 20% 02). Additionally, we found that decreases in ATP levels induced by 2-deoxyglucose (2 mM) or sodium cyanide (0.1 raM) are closely correlated with dopamine release from type I cells and electrical activity in the carotid sinus nerve elicited by these agents. The possible cause-effect relationship of these events is discusse

The long-term post-operative electromyographic evaluation of patients who have undergone carpal tunnel decompression

Producción CientíficaWe present the electromyographic (EMG) results ten years after open decompression of the median nerve at the wrist and compare them with the clinical and functional outcomes as judged by Levine's Questionnaire. This retrospective study evaluated 115 patients who had undergone carpal tunnel decompression at a mean of 10.47 years (9.24 to 11.36) previously. A positive EMG diagnosis was found in 77 patients (67%), including those who were asymptomatic at ten years. It is necessary to include both clinical and functional results as well as electromyographic testing in the long-term evaluation of patients who have undergone carpal tunnel decompression particularly in those in whom revision surgery is being considered. In doubtful cases or when there are differing outcomes, self-administered scales such as Levine's Questionnaire should prevail over EMG results when deciding on the need for revision surgery

La edad materna como factor de riesgo obstétrico. Resultados perinatales en gestantes de edad avanzada

Producción CientíficaObjetivo Comparar los resultados perinatales de gestantes mayores de 35 años con un grupo control (< 35 años). Diseño Estudio de cohortes históricas. Lugar Valladolid (España). Método: análisis univariante y estimación de RR. Variables estudiadas relativas a la epidemiología, desarrollo del embarazo y resultados perinatales. Resultados Se analizaron 1455 partos (355 correspondientes al grupo de estudio: 24,39%). Las gestantes de mayor edad presentaron más patología asociada al embarazo (29,2 vs 15,8%, p < 0,001) como diabetes gestacional (6.2%, p < 0.0029), metrorragia del primer trimestre (5.6%, p < 0.01), y amenaza de parto prematuro (3.9%, P < 0.007). Los estados hipertensivos del embarazo aunque fueron también más frecuentes no demostraron significación estadística. Se requirió inducción médica del parto con mayor frecuencia en el grupo de estudio (RR = 1.42; CI 95%:1.08-1.87). En el 47% de las gestantes nulíparas de edad avanzada se indicó una cesárea (RR = 1.63; CI 95%: 1.24-2.15). La tasa de mortalidad perinatal en el grupo de estudio fue 16.5‰ vs 2.77‰ en el grupo control. La morbilidad materna también fue superior en el grupo de edad avanzada (RR 5.98; CI 95% 1.35-26.54), fundamentalmente por complicaciones hemorrágicas. Conclusiones la edad materna avanzada se asocia con mayor frecuencia a patología gestacional y mayor incidencia de inducciones médicas del parto y tasa de cesáreas, especialmente en nulíparas. Todo ello repercute en la morbimortalidad materna y fetal, siendo un grupo poblacional de riesgo obstétrico que requiere una atención prenatal adecuada y trasciende el ámbito de la planificación sanitaria, dado el porcentaje de gestantes de edad avanzada en nuestro medio

Local sclerotherapy with Polydocanol (Aethoxysklerol®) for the treatment of Epistaxis in Rendu-Osler-Weber or Hereditary Hemorrhagic Telangiectasia (HHT): 15 years of experience*

Producción CientíficaHereditary Haemorrhagic Telangiectasia or Rendu-Osler-Weber syndrome is a rare autosomal dominant vascular disease characterized by mucocutaneous and gastrointestinal telangiectases and localized arteriovenous malformations in lung, brain and liver. Epistaxis, due to rupture of telangiectases of the nasal mucosa, is the most frequent clinical manifestation, leading in many cases to severe impairment of the quality of life in the patients. Though several treatments have been used to reduce epistaxis, none have been completely effective, with the exception of polydocanol (Aethoxysklerol®) in submucosal or subpericondrial injections, which was first presented in 2000 with very good results. After fifteen years using polydocanol in submucosal injections on 45 patients and with nearly 300 injections, we have observed that in 95% of all cases, their nose bleeds improved with respect to frequency and quantity without any important side effects. There was just one case of septal perforation, another with increased septal perforation, and one patient who suffered from dizziness and blurred vision for a few minutes. In this paper the results obtained using this technique over a fifteen-year period will be presented and evaluated

Comparison of two-step transient evoked otoacoustic emissions (TEOAE) and automated auditory brainstem response (AABR) for universal newborn hearing screening programs

Producción CientíficaBoth transitory auditory otoemissions (TEOAE) and automated auditory brainstem responses (AABR) are considered adequate methods for universal hearing screening. The goal of this study was to compare the results obtained with each device, applying the same screening procedure. MATERIALS AND METHODS:From 2001 to 2003, all the newborns in our health area (2454 infants) were evaluated with TEOAE (ILO92, otodynamics) and all those born from 2004 to 2006 (3117) were evaluated with AABR (AccuScreen, Fischer-Zoth). The population studied included all well newborns and those admitted to neonatal intensive care units (NICU). The first screening was normally undertaken with well babies during the first 48h of life, before hospital discharge. Infants referred from this first step underwent a second screening after hospital discharge, before they were a month old. RESULTS:The results from each study group were compared and analyzed for significant differences. TEOAE screening yielded 10.2% fail results from the first screening step; AABR gave 2.6%. In the second screening step, 2% of the newborns screened with TEOAE were referred, whereas 0.32% of those screened with AABR were referred. These differences are statistically significant. CONCLUSIONS:Although AABR screening tests involve a slightly higher cost in time and money than TEOAE, the results obtained compensate this difference. AABR gives fewer false positives and a lower referral rate; the percent of infants lost during follow-up is consequently smaller. Therefore, in our environment, universal newborn auditory screening with AABR is more effective than that with TEOAE

Evidence for two types of nicotinic receptors in the cat carotid body chemoreceptor cells

Producción CientíficaCurrent concepts on the location and functional significance of nicotinic receptors in the carotid body rest on a-bungarotoxin binding and autoradiographic studies. Using an in vitro preparation of the cat carotid body whose catecholamine deposits have been labeled by prior incubation with the tritiated natural precursor w3Hxtyrosine, we have found that nicotine induces release of w3Hxcatecholamines in a dose-dependent manner IC50s9.81 mM.. We also found that mecamylamine 50 mM. completely abolished the nicotine-induced release, while a-bungarotoxin 100 nM; f20 times its binding Kd. only reduced the release by 56%. These findings indicate that chemoreceptor cells, and perhaps other carotid body structures, contain nicotinic receptors that are not sensitive to a-bungarotoxin and force a revision of the current concepts on cholinergic mechanisms in the carotid body chemoreception

Health impact assessment of air pollution in Valladolid, Spain

Producción CientíficaTo estimate the attributable and targeted avoidable deaths (ADs; TADs) of outdoor air pollution by ambient particulate matter (PM10), PM2.5 and O3 according to specific WHO methodology. Design: Health impact assessment. Setting: City of Valladolid, Spain (around 300 000 residents). Data sources: Demographics; mortality; pollutant concentrations collected 1999–2008. Main outcome measures: Attributable fractions; ADs and TADs per year for 1999–2008. Results: Higher TADs estimates (shown here) were obtained when assuming as ‘target’ concentrations WHO Air Quality Guidelines instead of Directive 2008/50/EC. ADs are considered relative to pollutant background levels. All-cause mortality associated to PM10 (all ages): 52 ADs (95%CI 39 to 64); 31 TADs (95%CI 24 to 39). All-cause mortality associated to PM10 (<5 years): 0 ADs (95% CI 0 to 1); 0 TADs (95% CI 0 to 1). All-cause mortality associated to PM2.5 (>30 years): 326 ADs (95% CI 217 to 422); 231 TADs (95% CI 153 to 301). Cardiopulmonary and lung cancer mortality associated to PM2.5 (>30 years): ▸ Cardiopulmonary: 186 ADs (95% CI 74 to 280); 94 TADs (95% CI 36 to 148). ▸ Lung cancer : 51 ADs (95% CI 21 to 73); 27 TADs (95% CI 10 to 41).All-cause, respiratory and cardiovascular mortality associated to O3 (all ages): ▸ All-cause: 52ADs (95% CI 25 to 77) ; 31 TADs (95% CI 15 to 45). ▸ Respiratory: 5ADs (95% CI −2 to 13) ; 3 TADs (95% CI −1 to 8). ▸ Cardiovascular: 30 ADs (95% CI 8 to 51) ; 17 TADs (95% CI 5 to 30). Negative estimates which should be read as zero were obtained when pollutant concentrations were below counterfactuals or assumed risk coefficients were below one. Conclusions: Our estimates suggest a not negligible negative impact on mortality of outdoor air pollution. The implementation of WHO methodology provides critical information to distinguish an improvement range in air pollution control. INTRODUCTION Numerous epidemiological studies conducte

Sarcomas de partes blandas. Análisis de 42 casos

El objetivo de este estudio es valorar el pronóstico a largo plazo de una serie de pacientes tratados en nuestro hospital en relación con diversos factores clínicos, diagnósticos y terapéuticos que podrían condicionarlo. Se revisaron 123 pacientes tratado por tumores malignos de partes blandas entre los años 1979 y 1999, de estos solo 42 cumplieron las características para incluirles en nuestro estudio. Se valoró su evolución teniendo en cuenta las variables pronosticas identificadas en trabajos previamente publicados y nuestra propia experiencia y se realizó el estudio estadístico de las mismas. En el análisis estadístico del estudio se utilizó el programa SPSS versión 8.0WIN y se realizó el análisis de supervivencia mediante el método de Kaplan-Meier. El tiempo de supervivencia total descrito según este método para el total de los casos estudiados presenta una mediana de 33 meses con un error estándar de 8 y un intervalo de confianza del 95% de (17,49), el tiempo libre de enfermedad presenta una mediana de 9 meses con un error estándar de 2 y un intervalo de confianza del 95% de (6,12) y el tiempo de aparición de metástasis presenta una mediana de 26 meses con un error estándar de 5 y un intervalo de confianza del 95% de (17,35). A su vez se realizó el análisis bivariante de las múltiples variables pronosticas. El gran número de variables y la dispersión de la muestra hacen aconsejable estudios multicéntricos prospectivos más numerosos para obtener conclusiones definitivas sobre este tipo de tumores.The aim of this study is to evaluate the long-term prognosis of a series of patients treated in our hospital with regard to various clinical, diagnostic and therapeutic factors. A total of 123 patients who had been treated for malignant soft tissue tumours between 1979 and 1999 were reviewed. Of these, only 42 fulfilled the requirements to be included in our study. The outcome was evaluated taking into account prognostic variables identified in previously published studies and our own experience, and a statistical study of these factors as carried out with the Kaplan-Meier survival analysis method. The total survival time for all the cases studied was 33+8 (median + SE) months with a 95% confidence interval of 17.49 months. The time free of illness was 9+2 (median + SE) months with a 95% confidence interval of 6.12 months. The time-period until metastasis appeared was 26+5 (median + SE) months with a 95% confidence interval of 17.35 months. At the same time, the bivariant analysis of the many prognostic variables was performed. The high number of variables and the dispersion of the sample group suggest that it would be advisable to carry out more prospective, multicentric studies to reach definitive conclusions about this type of tumour