RESUMEN
Obesity is a global epidemic, affecting both developed and developing countries. The related metabolic consequences that arise from being overweight or obese are a paramount global health concern, and represent a significant burden on healthcare systems. Furthermore, being overweight or obese during pregnancy increases the risk of offspring developing obesity and other related metabolic complications in later life, which can therefore perpetuate a transgenerational cycle of obesity. Obesity is associated with a chronic state of low-grade metabolic inflammation. However, the role of maternal obesity-mediated alterations in inflammatory processes as a mechanism underpinning developmental programming in offspring is less understood. Further, the use of anti-inflammatory agents as an intervention strategy to ameliorate or reverse the impact of adverse developmental programming in the setting of maternal obesity has not been well studied. This review will discuss the impact of maternal obesity on key inflammatory pathways, impact on pregnancy and offspring outcomes, potential mechanisms and avenues for intervention.
Asunto(s)
Desarrollo Fetal/fisiología , Mediadores de Inflamación/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Complicaciones del Embarazo/metabolismo , Resultado del Embarazo , Femenino , Humanos , Inflamación/diagnóstico , Inflamación/etiología , Inflamación/metabolismo , Resistencia a la Insulina/fisiología , Obesidad/diagnóstico , Embarazo , Complicaciones del Embarazo/diagnósticoRESUMEN
A high-saturated-fat diet (HFD) during pregnancy and lactation leads to metabolic disorders in offspring concomitant with increased adiposity and a proinflammatory phenotype in later life. During the fetal period, the impact of maternal diet on skeletal muscle development is poorly described, despite this tissue exerting a major influence on life-long metabolic health. This study investigated the effect of a maternal HFD on skeletal muscle anabolic, catabolic, and inflammatory signaling in adult rat offspring. Furthermore, the actions of maternal-supplemented conjugated linoleic acid (CLA) on these measures of muscle phenotype were investigated. A purified control diet (CD; 10% kcal fat), a CD supplemented with CLA (CLA; 10% kcal fat, 1% total fat as CLA), a high-fat (HFD; 45% kcal fat from lard), or a HFD supplemented with CLA (HFCLA; 45% kcal fat from lard, 1% total fat as CLA) was fed ad libitum to female Sprague-Dawley rats for 10 days before mating and throughout gestation and lactation. Male offspring received a standard chow diet from weaning, and the gastrocnemius was collected for analysis at day 150. Offspring from HF and HFCLA mothers displayed lower muscular protein content accompanied by elevated monocyte chemotactic protein-1, IL-6, and IL-1ß concentrations. Phosphorylation of NF-κBp65 (Ser(536)) and expression of the catabolic E3 ligase muscle ring finger 1 (MuRF1) were increased in HF offspring, an effect reversed by maternal CLA supplementation. The present study demonstrates the importance of early life interventions to ameliorate the negative effects of poor maternal diet on offspring skeletal muscle development.
Asunto(s)
Dieta Alta en Grasa , Inflamación/prevención & control , Ácidos Linoleicos Conjugados/administración & dosificación , Músculo Esquelético/efectos de los fármacos , Atrofia Muscular/prevención & control , Efectos Tardíos de la Exposición Prenatal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Mediadores de Inflamación/metabolismo , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Atrofia Muscular/patología , Embarazo , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Aumento de PesoRESUMEN
Environmental prenatal stress (EPS) has effects on fetuses that are long-lasting, altering their hormone levels, brain morphology and behavior when they reach maturity. In previous research, we demonstrated that EPS affects the expression of induced maternal behavior (MB), the neuroendocrine system, and morphology of the sexually dimorphic accessory olfactory bulb (AOB) involved in reproductive behavior patterns. The bed nucleus of the accessory olfactory tract (BAOT) is another vomeronasal (VN) structure that plays an inhibitory role in rats in the expression of induced maternal behavior in female and male virgins. In the present study, we have ascertained whether the behavioral, neuroendocrine, and neuromorphological alterations of the AOB found after EPS also appear in the BAOT. After applying EPS to pregnant rats during the late gestational period, in their female offspring at maturity we tested induced maternal behavior, BAOT morphology and plasma levels of testosterone (T), estradiol (E2), progesterone (P), adrenocorticotropic hormone (ACTH) and corticosterone (Cpd B). EPS: a) affected the induction of MB, showed a male-like pattern of care for pups, b) elevated plasma levels of Cpd B and reduced E2 in comparison with the controls, and c) significantly increased the number of BAOT neurons compared to the control females and comparable to the control male group. These findings provide further evidence that stress applied to pregnant rats produces long-lasting behavioral, endocrine and neuroanatomical alterations in the female offspring that are evident when they become mature.
Asunto(s)
Encéfalo/fisiología , Conducta Materna/fisiología , Efectos Tardíos de la Exposición Prenatal/psicología , Estrés Psicológico/fisiopatología , Hormona Adrenocorticotrópica/sangre , Animales , Corticosterona/sangre , Estradiol/sangre , Femenino , Humanos , Masculino , Bulbo Olfatorio/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Progesterona/sangre , Ratas , Ratas Wistar , Caracteres Sexuales , Conducta Sexual/psicología , Estrés Psicológico/psicología , Testosterona/sangreRESUMEN
BACKGROUND AND PURPOSE: Myasthenia gravis (MG) may become life-threatening if patients have respiratory insufficiency or dysphagia. This study aimed to determine the incidence, demographic characteristics, risk factors, response to treatment and outcome of these life-threatening events (LTEs) in a recent, population-based sample of MG patients. METHODS: A retrospective analysis of MG patients who presented with an LTE between 2000 and 2013 was performed. Participants were identified from a neuromuscular diseases registry in Spain that includes 648 patients with MG (NMD-ES). RESULTS: Sixty-two (9.56%) patients had an LTE. Thirty-two were classified as class V according to the MG Foundation of America, and 30 as class IVB. Fifty per cent were previously diagnosed with MG and median duration of the disease before the LTE was 24 months (3-406). The most common related factor was infection (n = 18). All patients received intravenous human immunoglobulin; 11 had a second infusion and six had plasma exchange. Median time to feeding tube removal was 13 days (1-434). Median time to weaning from ventilation was 12 days (3-176), and it was significantly shorter in late onset MG (≥50 years) (P = 0.019). LTEs improved <2 weeks in 55.8% but did not improve until after 1 month in 20% of patients. Four patients died. No other factors influenced mortality or duration of LTEs. CONCLUSIONS: The percentage of LTEs in MG patients was low, particularly amongst those previously diagnosed and treated for the disease. The significant percentage of treatment-resistant LTEs indicates that more effective treatment approaches are needed for this vulnerable sub-population.
Asunto(s)
Trastornos de Deglución/epidemiología , Miastenia Gravis/epidemiología , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Sistema de Registros , Insuficiencia Respiratoria/epidemiología , Adulto , Trastornos de Deglución/terapia , Nutrición Enteral/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Miastenia Gravis/terapia , Intercambio Plasmático/estadística & datos numéricos , Insuficiencia Respiratoria/terapia , Estudios Retrospectivos , Factores de Riesgo , España/epidemiologíaRESUMEN
The present study analyzes the interaction between prenatal stress and mother's behavior on brain, hormonal, and behavioral development of male offspring in rats. It extends to males our previous findings, in females, that maternal care can alter behavioral dimorphism that becomes evident in the neonates when they mature. Experiment 1 compares the maternal behavior of foster mothers toward cross-fostered pups versus mothers rearing their own litters. Experiment 2 ascertains the induced "maternal" behavior of the male pups, derived from Experiment 1 when they reached maturity. The most striking effect was that the males non-exposed to the stress as fetuses and raised by stressed foster mothers showed the highest levels of "maternal" behavior of all the groups (i.e., induction of maternal behavior and retrieving behavior), not differing from the control, unstressed, female groups. Furthermore, those males showed significantly fewer olfactory bulb mitral cells than the control males that were non-stressed as fetuses and raised by their own non-stressed mothers. They also presented the lowest levels of plasma testosterone of all the male groups. The present findings provide evidence that prenatal environmental stress can "demasculinize" the behavior, brain anatomy and hormone secretion in the male fetuses expressed when they reach maturity. Moreover, the nature of the maternal care received by neonates can affect the behavior and physiology that they express at maturity.
Asunto(s)
Conducta Materna/fisiología , Efectos Tardíos de la Exposición Prenatal , Caracteres Sexuales , Diferenciación Sexual/fisiología , Estrés Psicológico/fisiopatología , Animales , Animales Recién Nacidos , Femenino , Masculino , Embarazo , Complicaciones del Embarazo/psicología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Ratas , Ratas Wistar/crecimiento & desarrollo , Estrés Psicológico/complicacionesRESUMEN
BACKGROUND: Salvage and return of unwashed shed blood (USB) after total knee replacement (TKR) is an established blood-saving technique, but some authors question its efficacy and safety and suggest that the shed blood be washed before returning. We evaluated a colloid-based sedimentation method for improving and standardizing the quality of USB collected after TKR without the need for washing. METHODS: Experiments were performed to find the optimal colloid dose and sedimentation time using diluted donated venous blood. USB samples (n=52) were drawn from the reinfusion bag and mixed with hydroxyethyl starch or gelatine solutions (15-30%, colloid solution volume/total volume × 100). USB red blood cells (RBCs) were allowed to settle by gravity for 30 min, supernatant was evacuated from the syringe, and RBC concentrate was analysed. RBC recovery and other blood cell and chemical removal were calculated according to changes in USB volume and haematocrit. Twenty-five samples from leucodepleted packed RBCs were analysed as a comparator group. RESULTS: Mean haemoglobin (Hb) of USB was 10.9 g dl(-1). After colloid treatment, 90% of RBCs were recovered, and USB Hb was similar to that of leucodepleted packed RBCs (n=25) (18.9 vs 19.6 g dl(-1), respectively; P=NS). In addition, the procedure reduced USB content of leucocytes (60%), platelets (48%), total protein (76%), cytokines (70-77%), and plasma-free haemoglobin (53%), without major differences between colloids. CONCLUSIONS: Sedimentation of USB with colloid solutions provides a low-cost alternative for improving and standardizing the quality of salvaged USB after TKR.
Asunto(s)
Artroplastia de Reemplazo de Rodilla , Transfusión de Sangre Autóloga/métodos , Recolección de Tejidos y Órganos/métodos , Pérdida de Sangre Quirúrgica , Sedimentación Sanguínea , Coloides , Citocinas/sangre , Hemodilución/métodos , Humanos , Procedimientos de Reducción del Leucocitos/métodos , Subgrupos Linfocitarios , Cuidados Posoperatorios/métodosRESUMEN
There is extensive evidence in rats that prenatal environmental stress (PES) exposure and early postnatal altered maternal care, as a consequence of stress during gestation, can detrimentally affect the brain and behavioral development of the offspring. In order to separate the effect of PES on the fetuses from that on the behavior of the mother, in the present study, we used a cross-fostering procedure in which PES-fetuses were raised by non-stressed mothers and non PES-fetuses were raised by stressed mothers. In Experiment 1, non-stressed mothers showed significantly more maternal behavior than stressed mothers. In Experiment 2, when the female offspring from Experiment 1 reached maturity, they were tested for: (1) induced maternal behavior (MB), (2) plasma levels of corticosterone (Cpd B), progesterone (P), and estradiol (E(2)), (3) number of accessory olfactory bulb (AOB) mitral cells, and (4) c-fos expression measured in AOB and medial preoptic area (MPOA) neurons. We replicated our previous findings that the PES group reared by their own stressed mothers, when adult, attacked the young, expressed disorganized MB and showed altered Cpd B, P and E(2) levels, plus a male-like neuro-morphological pattern in the AOB, by comparison with the non-PES group, reared by their own non-stressed mothers. By contrast, when adult, the PES group reared by non-stressed mothers showed hormonal and morphological neuronal alterations, but they displayed appropriate (full) MB. The non-PES group raised by stressed mothers also showed altered hormone levels, but showed full MB and no morphological neuronal changes. Significant differences in the AOB and MPOA c-fos activity, related to whether or not MB was expressed, were found in the non-PES groups, but not in the PES group reared by non-stressed mothers. To our knowledge, this is the first study to document that adequate maternal care, early in development, can shape the subsequent expression of induced MB, overcoming neuro-morphological and hormonal alterations that are produced by prenatal environmental stress. We conclude that maternal care during early postnatal development can counteract detrimental effects of prenatal environmental stress, exerting long-lasting effects that modulate the behavioral phenotype of the offspring.
Asunto(s)
Conducta Materna/fisiología , Efectos Tardíos de la Exposición Prenatal/etiología , Estrés Psicológico/complicaciones , Animales , Animales Recién Nacidos , Femenino , Hormonas/sangre , Neuronas/metabolismo , Bulbo Olfatorio/patología , Proteínas Oncogénicas v-fos/metabolismo , Embarazo , Efectos Tardíos de la Exposición Prenatal/patología , Radioinmunoensayo/métodos , Ratas , Ratas WistarRESUMEN
Se presenta paciente de 55 años, sexo femenino politransfundida con falta de respuesta al tratamiento instituído, identificándose un Anti E con técnicas enzimáticas, que no fue detectado en Liss-Coombs. Está bien demostrado desde la literatura internacional que un 35 por ciento de anticuerpos reaccionan sólo con este método y que el 0,5 por ciento del total de los resultados son falsos positivos, se destaca la importancia de trabajar con esta metodología evaluando riesgos-beneficios.
We describe the case of a 55 years old woman that has the history of politransfusion but she hasn't responded to this treatment and it was identified in her serum sample an anti-E antibody that was active only by the enzyme test with gel method. As Literature describe that 35 per cent of alloantibodies only react with this method and 0,5 per cent has false positive result, it is relevant the fact of working with this method testing risk and benefits.
Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Pruebas de Enzimas , Tipificación y Pruebas Cruzadas Sanguíneas/métodos , Anticuerpos/sangre , Prueba de Coombs , Transfusión Sanguínea/métodosRESUMEN
Introduction: Obstructive sleep apnea syndrome (OSAS) is a common disease associated with significant morbidity, including excessive daytime sleepiness, cardiovascular disease and stroke. Method: We studied prospectively the patients sent to our sleep laboratory for polysomnography (PSG) during 6 months. One-hundred patients were interviewed with a sleep questionnaire, 3 of them were ruled out because the lacking of PSG and 2 who no completed the Epworth sleep scale (ESS). Results: Out of the 95 patients, there were 85 men and 10 women, with a mean age of 47.4 +/- 12.5 years, obesity was found in 42.5 percent, an ESS greater than 11 points was found in 56.8 percent, loud snoring in 93.7 percent, breathing cessation in 68.4 percent, excessive daytime somnolence in 57.9 percent. PSG revealed no OSAS in 14.7 percent, slight OSAS in 27.4 percent, moderate OSAS in 21 percent y severe OSAS in 36.8 percent. Body mass index and breathing cessation reported by the couple had the highest discriminative power with a sensibility of 87 percent and specificity of 50 percent for ruled out severe OSAS. Conclusion: A severe OSAS is less probable when there is absence of breathing cessation during sleep reported by the couple and an IMC <30 Kg/m².
Introducción: El SAHOS presenta una alta prevalencia en estudios internacionales, con importantes repercusiones en los sistemas cardio, cerebrovascular y en la calidad de vida de las personas. Método: Estudiamos prospectivamente a los pacientes enviados para Polisomnografia (PSG) a nuestro laboratorio de sueño, en un período de 6 meses. Previo consentimiento informado, se les aplicó la Escala de Somnolencia de Epworth (EE) y un Cuestionario de Sueño. Fueron entrevistados 100 pacientes, excluyéndose 3 por no haberse realizado PSG y 2 que no completaron la EE. Resultados: Se analizaron 95 pacientes, 89,5 por ciento hombres, edad promedio 47,4 +/- 12,5 años, obesidad en 49,5 por ciento, EE mayor de 11 en 56,8 por ciento, ronquido en 93,7 por ciento, pausas respiratorias en 68,4 por ciento, somnolencia diurna excesiva en 57,9 por ciento, cansancio al despertar en 86,3 por ciento. La PSG no demostró SAHOS en 14,7 por ciento, hubo 27,4 por ciento con SAHOS leve, 21 por ciento> moderado y 36,8 por ciento> severo. Las variables presencia de pausas respiratorias observadas por la pareja e índice de masa corporal (IMC) predicen la ausencia de SAHOS severo, con una sensibilidad de 87 por ciento y especificidad de 50 por ciento. Conclusión: En la evaluación de pacientes con sospecha de SAHOS, la no observación de pausas respiratorias durante el sueño por parte de la pareja y el IMC menor de 30 Kg/m² hacen menos probable que exista un SAHOS severo.
Asunto(s)
Humanos , Masculino , Adulto , Femenino , Persona de Mediana Edad , Apnea Obstructiva del Sueño/diagnóstico , Polisomnografía , Encuestas y Cuestionarios , Factores de Edad , Índice de Masa Corporal , Trastornos de Somnolencia Excesiva , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Síndromes de la Apnea del Sueño/diagnósticoRESUMEN
La revisión sistemática y el metaanálisis forman parte de la investigación secundaria, la cual parte del estudio de las pruebas disponibles sobre una determinada intervención sanitaria, con el objeto de responder a cuestiones concretas, siguiendo una metodología explícita y rigurosa. El primer paso en su elaboración es la formulación de la pregunta de investigación, que definirá los criterios de inclusión de los estudios de nuestra revisión: metodología del estudio, participantes, intervenciones, comparaciones a estudiar y medidas de resultado. Estas características marcarán el protocolo de estudio y su correcta definición facilitará el resto del proceso. La siguiente etapa consiste en la búsqueda de estudios en la literatura científica sobre el tema a tratar, y la lectura crítica de los mismos para descartar en ocasiones simplemente con la lectura del título o el abstract y en otras revisando el artículo completo aquellos que no reúnen nuestros criterios de selección y quedarnos con los que finalmente serán incluidos. Estos estudios constituirán nuestra revisión, de ellos se extraerán los datos necesarios y se evaluarán tanto cualitativa como cuantitativamente. En aquellos casos en los que exista homogeneidad entre los estudios incluidos, y al menos dos de ellos presenten datos razonablemente combinables, se realizará un análisis cuantitativo denominado "metaanálisis", generalmente mediante la ayuda de programas estadísticos informatizados que facilitan este trabajo, y que permiten visualizar los resultados gráficamente en los denominados forest plot. La última fase de una revisión, al igual que en el resto de estudios epidemiológicos, consiste en interpretar los resultados obtenidos y extraer las correspondientes conclusiones, que en este tipo de estudios tendrán repercusiones tanto para la investigación, como para la práctica clínica
The systematic review and meta-analysis form a part of secondary research which begins with the study of the evidence available on a certain health care intervention in order to respond to specific questions by means of an explicit and rigorous methodology. The first step in its elaboration is the writing of the research question that will define the inclusion criteria of the studies of our review: study methodology, participants, interventions, comparisons to be studied and measurements of the results. These characteristics will define the study protocol and their correct definition will facilitate the rest of the procedure. The following stage consists in the search for studies in the scientific literature on the subject in question and the critical reading of them to rule out, sometimes only by reading the title or abstract and others by reading the complete article, those that do not fulfill our selection criteria. Finally, those remaining will be included in the study. These studies will make up our review and will be used to obtain the necessary data and to evaluate them both qualitatively and quantitatively. In those cases where there is homogeneity between the studies included and where at least two of them have reasonably combinable data, a quantitative analysis called meta-analysis will be conducted. This is generally done with the help of computerized statistical programs that aid this work and that make it possible to visualize the results graphically in the so-called forest plot. The last phase of the review, as in the rest of the epidemiological studies, consists in interpreting the results obtained and in drawing the corresponding conclusions. In this type of studies, they will have repercussions in both the research and clinical practice
Asunto(s)
Investigación Biomédica/métodos , Metaanálisis , Bases de Datos Bibliográficas , Sesgo , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Medicina Basada en la Evidencia/métodosRESUMEN
La estadística estudia los métodos científicos para recoger, organizar, resumir y analizar datos, permite obtener conclusiones válidas y tomar decisiones razonables basadas en el análisis. La estadística es, por tanto, la ciencia que recoge, clasifica y analiza la información que se presenta habitualmente mediante datos agregados que permiten que las observaciones puedan cuantificarse, medirse, estimarse y compararse utilizando medidas de tendencia central, medidas de distribución, métodos gráficos, etc. La estadística aplicada trata sobre cómo y cuándo utilizar los procedimientos matemáticos (estadística matemática) y cómo interpretar los resultados que se obtienen. Así, la bioestadística es la rama de la estadística que enseña y ayuda a investigar en todas las áreas de las ciencias de la vida donde la variabilidad es la regla. Se divide en dos grandes ramas, la bioestadística descriptiva y la bioestadística analítica o inferencial. La estadística descriptiva resume la información contenida en los datos recogidos y la estadística inferencial demuestra asociaciones y permite hacer comparaciones entre características observadas
Statistics is the study of the scientific methods for collecting, organizing, summarizing, and analyzing data; it makes it possible to reach valid conclusions and make reasonable decisions on the basis of the analysis. Statistics is, therefore, the science of gathering, classifying, and analyzing information that is usually presented through aggregated data that enable observations to be quantified, measured, estimated, and compared using measurements of central tendency, measurements of distribution, graphical methods... Applied statistics deals with how and when to use the mathematical procedures (mathematical statistics) and how to interpret the results that are obtained using these procedures. Likewise, biostatistics is the branch of statistics that teaches and helps the investigator to carry out research in all of the different branches of the life sciences where variability is the rule. Biostatistics can be divided into two main areas: descriptive biostatistics and analytical or inferential statistics. Descriptive statistics summarizes the information contained in the data collected and inferential statistics demonstrates associations and makes it possible to make comparisons among the characteristics observed
Asunto(s)
Epidemiología Descriptiva , Interpretación Estadística de Datos , Investigación Biomédica/métodos , Recolección de Datos/métodos , Factores Epidemiológicos , Análisis de RegresiónRESUMEN
Para realizar un proyecto de investigación debemos obtener datos de la población objetivo, que se define como el conjunto de elementos del cual se quiere conocer cierto aspecto. En algunos estudios cada elemento de la población puede ser medido realmente, lo cual es posible solamente si la población no es muy numerosa y si todos los elementos son accesibles. Pero lo habitual es que el estudio completo de la población sea inviable, ya que el trabajo empírico necesario es costoso e implica mucho tiempo y recursos. Para obtener resultados confiables no es necesario obtener los datos de todos los elementos poblacionales, es suficiente recoger las variables de un subconjunto de elementos denominado muestra. El estudio tendrá la validez y la fiabilidad necesarias si este subconjunto es representativo de la población objetivo y los resultados obtenidos son extrapolables a la misma. Existen distintas técnicas o procedimientos para seleccionar la muestra, dependiendo del tiempo, de los recursos económicos y de la naturaleza de los elementos poblacionales. El conjunto de estas técnicas se denomina muestreo. En el diseño del estudio se debe definir el tamaño muestral necesario; su cálculo está relacionado con ciertos problemas que estudia la Inferencia Estadística y que permitirán extraer conclusiones científicamente válidas a la población
To carry out a research project it is necessary to obtain data from the target population, which is defined as the set of elements about which we aim to find out a certain aspect. In some studies, this aspect can be directly measured in each element of the population; however, this is only possible if the population is not very large and if all of the elements are accessible. In the vast majority of cases, it is not viable to study the entire population because the empirical work necessary is expensive and involves much time and resources. To obtain reliable results, it is not necessary to obtain all of the data from all of the elements of the population; it is sufficient to collect the variables in a subgroup of elements called the sample. Unless this subgroup is representative of the target population, the results of the study cannot be extrapolated and will not be valid or reliable for the target population as a whole. There are different techniques or procedures to select the sample, depending on the time and financial resources available, as well as the nature of the elements of the population. This set of techniques is called sampling. When designing a study, it is necessary to define the necessary sample size, which involves certain problems studied by Inferential Statistics and will enable scientifically valid conclusions to be reached regarding the population
Asunto(s)
Proyectos de Investigación/normas , Investigación Biomédica/métodos , Selección de Paciente , Tamaño de la Muestra , Diseño de Investigaciones Epidemiológicas , Interpretación Estadística de Datos , Estadística como AsuntoRESUMEN
Los estudios analíticos permiten estudiar y verificar hipótesis causales, y los ensayos clínicos, en particular, aportan el mayor nivel de evidencia en la comprobación de estas hipótesis. Un ensayo clínico aleatorio (ECA) es un experimento planificado en el que, de forma prospectiva, se comparan dos o más intervenciones preventivas, curativas o rehabilitadoras, que son asignadas de forma individualizada y aleatoria a un grupo de pacientes para estudiar el efecto de estas intervenciones en el hombre. Para su realización es necesario tener en cuenta una serie de aspectos metodológicos, como la elección de la muestra de sujetos a partir de unos adecuados criterios de selección, asignación aleatoria de los sujetos a los diferentes grupos de intervención, elección del grupo control, enmascaramiento o cegamiento de algunos o todos los sujetos que intervienen en el estudio, y descripción de pérdidas y abandonos para un correcto análisis de los datos. Las características de este tipo de estudios, realizados sobre humanos, implican la necesidad del cumplimiento de unos requisitos éticos y legales que protejan a los participantes, motivo por el cual es imprescindible la obtención de un consentimiento informado, así como el informe favorable de un Comité Ético de Investigación Clínica para su realización
Analytic studies make it possible to study and verify causal hypotheses and clinical studies, specifically contribute the greatest level of evidence in the verification of these hypothesis. A randomized clinical trial (RCT) is a planned experiment in which two or more preventive, curative or rehabilitating interventions, assigned in an individualized and random way to a group of patients to study the effect of these interventions in man, are compared. To do so, a series of methodological aspects must be taken into account, such as the choice of the subject sample based on adequate screening criteria, random allotment of the subjects to the different intervention groups, choice of the control group, masking or blinding of some or all the subjects participating in the study and description of losses and drop-outs for correct analysis of the data. The characteristics of the type of study, conducted in humans, imply the need for the fulfillment of some ethical and legal requirements that protect the participants, reason why it is essential to obtain an informed consent and favorable report from the Ethics Committee for its conduction
Asunto(s)
Recolección de Datos/métodos , Investigación Biomédica/métodos , Ensayos Clínicos como Asunto , 51706 , Sesgo de SelecciónRESUMEN
El diseño de un estudio consiste en un conjunto de procedimientos, métodos y técnicas mediante las cuales el investigador selecciona la variable respuesta, define los criterios de selección de la población en estudio, calcula el número de sujetos necesarios en la(s) muestra(s) y selecciona las variables que deben medirse, con el objetivo de estimar la magnitud del efecto o de la respuesta observada, controlar los factores de confusión e interpretar los resultados. La elección del tipo de diseño dependerá fundamentalmente del objetivo del estudio, de las hipótesis planteadas y de los recursos de los que disponga el grupo de investigación. Los estudios descriptivos permiten analizar cómo son y cómo se manifiestan los fenómenos de salud y permiten al investigador detallar las características más importantes de la enfermedad o del evento en estudio. Por el contrario, los estudios analíticos pretenden encontrar las causas que ocasionan esos fenómenos y estudian la relación entre diferentes variables, generalmente entre una causa y un efecto
The design of the study consists in a combination of procedures, methods and techniques by which the investigator selects the response variable, defines study population selection criteria, calculates the number of subjects needed in this sample(s) and selects the variables that should be measured in order to estimate the magnitude of the effect or of the response observed, to control confounding factors and interpret the results. The choice of the type of design will basically depend on the study objectives, and the hypotheses proposed and on the resources that the research group has. Descriptive studies make it possible to analyze how the health phenomena are manifested and what they are and make it possible for the investigator to detail the most important characteristics of the disease or event under study. On the contrary, analytic studies aim to find the causes of these phenomena and studied the relationship between different variables, generally between a cause and effect
Asunto(s)
Recolección de Datos/métodos , Investigación Biomédica/métodos , Epidemiología Descriptiva , Estudios Epidemiológicos , Observación/métodos , Estudios de Cohortes , Estudios de Casos y ControlesRESUMEN
The most successful therapy for acute liver failure is liver transplantation. However, due to the low number of donors, organ support therapies need to be used as a bridge to liver transplantation. Molecular Adsorbents Recirculating System (MARS) is a dialysis treatment that uses a recirculating dialysate containing albumin. This allows the removal of both hydrosoluble and albumin-related substances. This system improves hepatic encephalopathy, renal dysfunction and some clinical parameters in acute liver failure, but there is no clear decrease in mortality. We report three women aged 23, 21 and 61 years, that were subjected to liver transplantation, in whom this therapy was successfully used.
Asunto(s)
Humanos , Adulto , Femenino , Persona de Mediana Edad , Hígado Artificial , Trasplante de Hígado , Fallo Hepático Agudo , Insuficiencia Hepática/terapiaRESUMEN
The GABAA antagonist bicuculline, intracranially infused into the accessory olfactory bulb (AOB), facilitated the expression of maternal behavior (MB) in virgin Wistar female rats. Behavioral effects were observed 24 hours after infusion and were injection dependent. Pheromonal stimuli, generated by the pups, are thought to exert an inhibitory effect on vomeronasal nuclei involved in MB in virgin rats. The present study investigated the possibility that a decrement in AOB output, resulting from long-term compensatory synaptic changes to chronic bicuculline infusion, would facilitate the expression of MB. The implications of our findings for the mechanisms involved in the induction of MB and the maternal experience effect are discussed.
Asunto(s)
Bicuculina/farmacología , Convulsivantes/farmacología , Bombas de Infusión , Conducta Materna/efectos de los fármacos , Bulbo Olfatorio/efectos de los fármacos , Animales , Bicuculina/administración & dosificación , Convulsivantes/administración & dosificación , Femenino , Ratas , Ratas WistarRESUMEN
Development of sex differences in the locus coeruleus (LC) is investigated. The LC is a sexually dimorphic structure in which the female manifests a larger volume and greater number of neurons than do males. Male and female Wistar rats were sacrificed on prenatal days (E) 16 and 20 and postnatally (P) on days 1, 3, 7, 15, 35, 45, 60, and 90. Male and female rats show a continuous increase in the number of neurons after birth that stops in the males by P45 and in females by P60. These findings point out the existence of different patterns of development in male and female rats and may suggest that sex differences could be established because of the existence of a differential period of neurogenesis in both sexes in the postpubertal period.
Asunto(s)
Envejecimiento/fisiología , Locus Coeruleus/embriología , Locus Coeruleus/crecimiento & desarrollo , Neuronas/citología , Ratas Wistar/embriología , Ratas Wistar/crecimiento & desarrollo , Caracteres Sexuales , Animales , Animales Recién Nacidos/embriología , Animales Recién Nacidos/crecimiento & desarrollo , Apoptosis/fisiología , Recuento de Células , Diferenciación Celular/fisiología , División Celular/fisiología , Ciclo Estral/fisiología , Femenino , Feto , Locus Coeruleus/citología , Masculino , Neuronas/metabolismo , Ratas , Ratas Wistar/metabolismoRESUMEN
In the last two decades, important changes in medical training and care have occurred in Chile. The number of medical schools has been doubled, exceeding the national availability of professors and qualified training fields. The quality assessment and accreditation of medical training and care is insufficient in Chile. A National Autonomous Corporation of Certification of Medical Specialties, has certified more than 4,000 physicians in 44 specialties. The Chilean Association of Faculties of Medicine has accredited training centers during the last four decades. The National Commission of Undergraduate Training Accreditation, has developed a voluntary system for medical school accreditation. The Academy supports these strategies and considers that accreditation does not threaten institutions or individuals. It is rather a mechanism that identifies strengths and weaknesses of institutions and programs. This will finally result in better quality in medical training and patient care.
Asunto(s)
Academias e Institutos , Educación Médica , Calidad de la Atención de Salud , Chile , Humanos , Control de CalidadRESUMEN
It has been demonstrated that the posteromedial cortical amygdaloid nucleus (PMCo), is sexually dimorphic. It is shown (Experiment 1) that male orchidectomy on the day of birth (D1) decreases the volume and number of neurons of the PMCo, while a single injection of propionate testosterone to the female on D1 masculinizes the PMCo in this gender. Since male gonadectomy on D1 (Experiment 2) is counteracted by a single injection of estradiol benzoate in males it has been suggested that the masculinization of the PMCo is due to the aromatization of testosterone to estradiol in this structure. These findings support the hypothesis that the development of sex differences in structures that belong to the vomeronasal system are due to the aromatization of testosterone to estradiol shortly after birth.
Asunto(s)
Amígdala del Cerebelo/efectos de los fármacos , Estradiol/farmacología , Caracteres Sexuales , Amígdala del Cerebelo/citología , Amígdala del Cerebelo/fisiología , Animales , Animales Recién Nacidos , Recuento de Células , Femenino , Masculino , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/fisiología , Orquiectomía , Ratas , Ratas WistarRESUMEN
El Manual de Auto-cuidado del lesionado medular, se presenta como una alternativa de capacitación, promoción e información dirigida fundamentalmente a las personas con lesiones o afectaciones de la médula espinal, así como a los técnicos y profesionales que laboran en el Campo de la Rehabilitación: enfermería, medicina, trabajo social, psicología, fisioterapia, etc. Se pretende que este Manual sea de mucha utilidad para los técnicos y profesionales de rehabilitación integral debido a que ellos tienen la responsabilidad primaria para orientar, adiestrar y capacitar en su auto-cuidados a las personas con lesión medular, desde su llegada a los centros y establecimientos de salud para recibir los primero y más importantes conocimientos después de lesionarse. De igual manera la identificación y tratamiento temprano de las complicaciones de una lesión medular, mejorar la calidad de vida de las personas con discapacidad, por que lo que el papel de los trabajadores de rehabilitación adquiere mayor relevancia...