Etiopathogenesis of drug dependence: an explanatory synthesis from an epigenetic perspective / Etiopatogenia de las drogodependencias: una síntesis explicativa desde una perspectiva epigenética / Etiopatogenia das toxicodependências: uma síntese explicativa a partir de uma perspectiva epigenética

The use of substances with addictive potential is a relevant health problem. Scientific evidence suggests that the underlying mechanisms that regulate behavioral processes in addictions involve a complex interplay between genetic and environmental factors. Therefore, this narrative review aims to provide a framework to synthesize the evidence on gene-environment-agent interactions from the perspective of the natural history of the disease and the stages of the addictive process for alcohol, nicotine, cannabis, psychostimulants, and opioids. In this review, we conducted an exhaustive literature search without time limits in PubMed, Ebsco, Lilacs, and SciELO, reviewing the title and abstract we selected original articles in humans or animals that addressed the etiology of addictions according to the methodological approach of gene-environment (G-E) interaction, including articles in Spanish, English, and Portuguese. Genetic studies have revealed the critical role of epigenetic modifiers (histone acetylation) in maintaining brain homeostasis in pathological conditions and focusing on G-E interactions will also allow characterizing subgroups (based on environmental factors) at high risk for addictive behaviors that can be targeted for specific interventions, Thus, treatment strategies should encompass a combination of psychosocial interventions with gene therapy involving pharmacological manipulations of histones that may contribute to design better therapies and perhaps lead to more successful management of drug dependencies.

El consumo de sustancias con potencial adictivo es un problema relevante de salud. La evidencia científica sugiere que los mecanismos subyacentes que regulan los procesos comportamentales en las adicciones involucran un complejo interjuego entre factores genéticos y ambientales. Por lo tanto, esta revisión narrativa tiene como objetivo aportar un marco de referencia que permita sintetizar la evidencia sobre interacciones genes- ambiente-agente desde la perspectiva de la historia natural de la enfermedad y los estadios del proceso adictivo para: alcohol, nicotina, cannabis, psicoestimulantes y opioides. En esta revisión realizamos una búsqueda exhaustiva de la literatura sin límites de tiempo en PubMed, Ebsco, Lilacs y SciELO, revisando el título y el resumen se seleccionaron artículos originales en humanos o animales que abordaran la etiología de las adiciones según el enfoque metodológico de interacción entre genes y ambiente (G-A), incluyendo artículos en español, inglés y portugués. Los estudios genéticos han revelado el papel crítico de los modificadores epigenéticos (acetilación de las histonas) en mantener la homeóstasis cerebral en condiciones patológicas y enfocarse en las interacciones G-A también permitirá caracterizar subgrupos (basados en los factoresambientales) de alto riesgo para conductas adictivas que pueden ser objeto de intervenciones específicas, por lo que, las estrategias de tratamiento deben englobar una combinación de intervenciones psicosociales con terapia génica que involucren las manipulaciones farmacológicas de las histonas que pueden contribuir a diseñar mejores terapias y tal vez conducir a un manejo más exitoso de las drogodependencias.

O consumo de substâncias com potencial viciante é um relevante problema de saúde. Evidências científicas sugerem que os mecanismos subjacentes que regulam os processos comportamentais em vícios envolvem uma interação complexa entre fatores genéticos e ambientais. Portanto, esta revisão narrativa visa fornecer um quadro de referência que permita sintetizar as evidências sobre interações gene-ambiente-agente sob a perspectiva da história natural da doença e as etapas do processo de dependência para: álcool, nicotina, cannabis, psicoestimulantes e opióides. Nesta revisão, realizamos uma busca exaustiva da literatura sem limites de tempo no PubMed, Ebsco , Lilacs e SciELO, revisando o título e o resumo, foram selecionados artigos originais em humanos ou animais que abordassem a etiologia dos acréscimos de acordo com a abordagem metodológica de interação entre genes e ambiente (GA), incluindo artigos em espanhol, inglês e português. Estudos genéticos revelaram o papel crítico dos modificadores epigenéticos (acetilação de histonas) na manutenção da homeostase cerebral em condições patológicas, e o direcionamento das interações GA também permitirá caracterizar subgrupos (com base em fatores ambientais) de alto risco para comportamentos aditivos que podem ser alvo de ataques específicos. intervenções, portanto, as estratégias de tratamento devem abranger uma combinação de intervenções psicossociais com terapia gênica envolvendo manipulações farmacológicas de histonas que podem contribuir para projetar melhores terapias e talvez levar a um manejo mais bem-sucedido das dependências de drogas.

Agro-food waste employed to design and develop culture media for fungal growth

Aim: Waste from the agricultural and food industries could be used as a source of nutrients in the culture media for fungal growth and thus reduce environmental pollution and the cost of bioprocesses. In this work, it was determined if some agro-food waste can improve the mycelial growth of fungi and laccase production.Methodology: Culture media with agar and vermicompost, vermiwash, calcined pork bones or fish waste for mycelial growth of fungi were elaborated. The laccase activity of each strain grown in all culture media was also estimated. Results: Pleurotus eryngii, Lentinula edodes, Pleurotus ostreatus, Flammulina velutipes, Pleurotus citrinopileatus and Ganoderma lucidum grew in all culture media, except Lentinula edodes, obtaining in general higher biomass and radial growth rate than those observed on potato-dextrose agar. The maximum laccase activity was found in Pleurotus citrinopileatus cultivated in fish waste medium. The C: N ratio, ashes and pH were important factors for the growth of the strains. Interpretation: There were significant differences in biomass concentration and laccase activity in the designed culture media. These results provide an interesting alternative for the use of wastes and metabolites production of industrial interest.

CASO CLÍNICO: INTOLERANCIA A ANTIINFLAMATORIOS NO ESTEROIDES (AINES): INCLUIDO PARACETAMOL

Se presentan dos pacientes con urticaria y angioedema inducidos por reacción cruzada a AINES, incluido el Paracetamol. Los autores realizan una descripción diagnóstica y propuesta terapéutica.

Epidemiología de las meningitis bacterianas en niños en un hospital pediátrico: 2011-2016 / Epidemiology of bacterial meningitis in children at a pediatric hospital: 2011-2016

Introducción: Las meningitis bacterianas en niños son causa de importante morbimortalidad. Los principales agentes etiológicos son Neisseria meningitidis, Streptococcus pneumoniae y Haemophilus influenzae. En los últimos años, luego de la introducción sucesiva de vacunas conjugadas al calendario nacional de inmunizaciones, se ha visto un cambio en la epidemiología de estas infecciones. Objetivo: Describir las características clínicas, epidemiológicas y evolutivas de los niños hospitalizados con meningitis bacteriana confirmada microbiológicamente entre 2011 y 2016 en un hospital de tercer nivel de complejidad. Materiales y métodos: Cohorte retrospectiva. Se incluyeron niños entre 1 mes de vida y 17 años con cuadro clínico compatible con meningitis bacteriana y cultivo positivo y/o PCR en líquido cefalorraquídeo y/o hemocultivos positivos para Neisseria meningitidis, Streptococcus pneumoniae y Haemophilus influenzae b. Se registraron las características demográficas, clínicas y evolutivas hasta los 30 días del egreso. Se utilizó mediana y rango intercuartilo (RIC) para variables continuas y porcentaje para variables categóricas. Se utilizó Stata 10. Resultados: n=65. Edad: mediana de 9 meses (RIC 4-35). Varones: 58% (n=38). Se identificó Neisseria meningitidis en un 48% (n=31), Haemophilus influenzae b en un 26% (n=17) y Streptococcus pneumoniae en un 26% (n=17). El 26% (n=17) de los pacientes presentaba alguna comorbilidad. Tuvieron hemocultivos positivos el 62% (n = 40) de los pacientes y 86% (n=55) de los líquidos cefalorraquídeos. Todos los pacientes recibieron tratamiento antimicrobiano con ceftriaxona tanto como tratamiento empírico como definitivo y 92% (n=60) recibieron corticoides empíricos. La mediana de días de internación fue de 11 (RIC 8-17). El 28% (n=18) requirió cuidados intensivos, y el 8% (n=5) falleció. Durante el período de estudio se observó que la frecuencia de meningitis por Streptococcus pneumoniae disminuyó en el final del estudio (9% en 2016 vs 60% en 2011), mientras que la frecuencia de meningitis por Neisseria meningitidis en 2016 fue mayor que al inicio del período (64% en 2016 vs. 40% en 2011). La frecuencia de identificación de Haemophilus influenzae b se mantuvo estable. Conclusiones: Las meningitis bacterianas confirmadas por Neisseria meningitidis, Streptococcus pneumoniae y Haemophilus influenzae b prevalecieron en niños menores de 12 meses. En esta cohorte se observó un predominio de las infecciones por Neisseria meningitidis en los últimos años, y una disminución en la frecuencia de meningitis por Streptococcus pneumoniae en el período post introducción de la vacuna conjugada 13 valente al calendario nacional de inmunizaciones. (AU)

Introduction: In children, bacterial meningitis is an important cause of morbidity and mortality. The main etiological agents are Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae. Over the last years, the successive introduction of conjugated vaccines in the national immunization calendar has led to a change in the epidemiology of these infections. Objective: To describe the clinical and epidemiological features and outcome of children admitted because of microbiologically confirmed meningitis seen between 2011 and 2016 at a tertiary care hospital. Material and methods: A retrospective cohort study was conducted. Children between 1 month of life and 17 years of age with clinical features compatible with bacterial meningitis and positive cultures and/or PCR in cerebrospinal fluid (CSF) and/or positive blood cultures for Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae b were included. Demographic, clinical, and outcome features were recorded until 30 days after discharge. Median and interquartile range (IQR) were calculated for continuous variables and percentages for categorical variables. The Stata 10 program was used. Results: n=65. Age: median was 9 months (IQR 4-35). Boys: 58% (n=38). Neisseria meningitidis was identified in 48% (n=31), Haemophilus influenzae b in 26% (n=17), and Streptococcus pneumoniae in 26% (n=17). Overall, 26% (n=17) of the patients presented with comorbidities. Positive blood cultures were found in 62% (n = 40) and positive CSF cultures in 86% (n=55) of the patients. All patients received antimicrobial treatment with ceftriaxone both empirically and as final treatment and corticosteroids were empirically started in 92% (n=60). Median hospital stay was 11 days (IQR 8-17). Overall, 28% (n=18) required intensive care and 8% (n=5) of the patients died. The incidence of meningitis due to Streptococcus pneumoniae was observed to diminish at the end of the study period (9% in 2016 vs 60% in 2011), while the incidence of meningitis due to Neisseria meningitidis in 2016 was higher than at the end of the study period (64% in 2016 vs. 40% in 2011). The frequency of identification of Haemophilus influenzae b remained stable. Conclusions: Confirmed bacterial infections due to Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae b were prevalent in infants younger than 12 months of age in this cohort of patients. Infections due to Neisseria meningitidis predominated over the last years and the incidence of meningitis due to Streptococcus pneumoniae diminished after the introduction of the 13 valent conjugated vaccine was introduced in the national immunization calendar.(AU)

Desarrollo de una Interfaz Visual del Metabolismo de Glucosa Basada en Modelos Matemáticos Compartimentales / Development of a Visual Interface of Glucose Metabolism Based on Compartment Mathematical Models

RESUMEN La diabetes es una pandemia mundial cuya incidencia ha aumentado en las últimas décadas. Por tal motivo, es prioritario proponer estrategias para su diagnóstico, tratamiento y seguimiento. Uno de los enfoques recientes en el tratamiento de la diabetes es el monitoreo continuo, el cual permite tener suficiente información sobre el estado metabólico del paciente a lo largo del día. Esta información puede servir para simular pacientes virtuales que sean herramientas para proponer estrategias de tratamiento. Por tanto, el objetivo de esta investigación es proponer una interfaz visual que simule pacientes virtuales, a partir de un conjunto de modelos matemáticos compartimentales que permiten ingresar parámetros del metabolismo y modificaciones en el tratamiento. El desarrollo de la interfaz se realizó en MATLAB® y simula tres tipos de pacientes (sano, diabético tipo I y diabético tipo II). Los resultados muestran una interfaz que presenta de manera ilustrativa el funcionamiento de los modelos matemáticos y permite una visualización del estado metabólico del paciente; así como el manejo de medicamentos e ingesta. Una limitante de esta investigación es la validación de la interfaz con datos experimentales de los tres tipos de pacientes. Una vez validada, esta herramienta aportaría en el desarrollo de tecnología in silico para la generación de pacientes virtuales.

ABSTRACT Diabetes is a pandemic disease whose incident rate has been rising in the last decades. Therefore, it is important to propose strategies for its diagnosis, treatment and monitoring. One of the recent approaches on diabetes treatment is the continuous monitoring, which provides enough information about the metabolic state of the patient throughout the day. This information can be used to simulate virtual patients which are useful tools in treatment strategies. Thus, the objective of this research is to propose a visual interface to simulate virtual patients, this is based on compartmental mathematical models considering changes in metabolic parameters and treatment modifications. The interface was made in MATLAB® and simulates three kinds of patients (healthy, type I diabetic, type II diabetic). The results show an interface that presents the functionality of the mathematical models in an illustrative way and it allows the visualization of the metabolic state of the patient; as well as the medication usage and meal intake. A limitation of this approach is the validation of the interface with experimental data of the three kinds of patients. Once it was validated, this tool could contribute to the development of in silico technology to generate virtual patients.

Seguridad y eficiencia de sedación balanceada con propofol y remifentanil en endoscopia digestiva alta diagnóstica. Una experiencia exitosa / A Successful Experience: Safety and Efficiency of Balanced Sedation with Propofol and Remifentanil in Diagnostic Endoscopy

Resumen La sedación es una técnica anestésica de amplio uso en los procedimientos endoscópicos digestivos actuales dado su claro beneficio en la tolerancia y comodidad para el paciente y el endoscopista. El medicamento de mayor uso en la actualidad para utilizarse como monosedación es el propofol, pero los esquemas balanceados utilizando más de un medicamento ahora son ampliamente usados en endoscopia diagnóstica o terapéutica. La sedación balanceada utilizando propofol y remifentanilo permite la potenciación sinérgica de un sedante con un opioide de ultracorta acción, lo que a su vez favorece la disminución respectiva de cada dosis. Se presenta una serie de 1148 pacientes llevados a endoscopia digestiva alta diagnóstica con dosis promedio de remifentanilo de 0,9 µg/kg de peso y de propofol de 0,47 mg/kg de peso, sin eventos adversos graves, con excelente satisfacción para el endoscopista y con muy bajo costo de la dosis por medicamento, con lo que se infiere que es un esquema seguro y eficiente.

Abstract Sedation is an anesthetic technique that is widely used in current digestive endoscopic procedures because of its clear benefits for patients' tolerance and comfort and for the endoscopist. Propofol is the most commonly used drug in monosedation, but balanced regimens using more than one drug are now widely used in diagnostic and therapeutic endoscopy. Balanced sedation using Propofol and Remifentanil allows synergistic potentiation of a sedative with an ultra-short acting opioid which in turn favors decreases of each dose. This is a series of 1,148 patients who underwent diagnostic endoscopy under balanced sedation with average Remifentanil doses of 0.9 mcg/kg of body weight and average Propofol doses of 0.47 mg/kg of body weight. There were no serious adverse events, endoscopists were highly satisfied with the procedures, and costs per drug dose were very low. This is clearly a safe and efficient scheme.

Mucosa gástrica heterotópica en esófago cervical: presentación de un caso de compromiso circunferencial con estenosis franqueable / A Case Report of Circumferential Presentation with Stricture of Heterotopic Gastric Mucosa in the Cervical Esophagus

La mucosa gástrica heterotópica en esófago cervical (MGHEC) es una condición probablemente subdiagnosticada. La gran mayoría de los pacientes son asintomáticos y su detección es un hallazgo incidental. En los pacientes sintomáticos, las manifestaciones se asocian con cambios no neoplásicos o neoplásicos, que permiten categorizarlos en cinco tipos. A la categoría tipo III corresponde el caso presentado del paciente, con disfagia y globus faríngeo por MGHEC de compromiso circunferencial con estenosis franqueable. Al momento de esta publicación, solo se encontraron siete casos similares en la literatura mundial. La detección de MGHEC (apoyada en nuevas tecnologías de imagen como la cromoendoscopia) puede ser un indicador de calidad en el desempeño endoscópico, similar a la detección de adenomas en colonoscopia.

Heterotopic gastric mucosa in the cervical esophagus is a condition that is probably underdiagnosed. The vast majority of patients are asymptomatic, and detection is an incidental finding. In symptomatic patients, manifestations are associated with non-neoplastic or neoplastic changes that allow categorization into five types. The case presented here is a patient who had Type III with dysphagia and pharyngeal globus due to heterotopic gastric mucosa in the cervical esophagus with circumferential presentation with stenosis. At the time of publication, only seven similar cases could be found in the literature. Detection, supported by new imaging technologies such as chromoendoscopy, may be an indicator of the quality of endoscopic performance in a manner that is similar to detection of adenomas in colonoscopy.

Impacto de 10 años de vigilancia de colonización con enterococos resistentes a vancomicina (ERV) en un hospital pediátrico de alta complejidad / 10 year impact of monotoring colozation with vancomycin resistant enterococci (VRE) in a tertiary care pediatric hospital

Se demostro que la vigilancia activa de colonización con enterococos resistentes a vancomicina (ERV) resulta costo-efectiva y que es capaz de limitar la presencia de esos patógenos en los hospitales. El objetivo de este trabajo fue evaluar el impacto de una forma de vigilancia menos estricta a través de los resultados de los estudios de prevalencia de un día y del número anual de pacientes infectados con ERV. En los cortes de prevalencia, se estudiaron todos los pacientes hospitalizados en días determinados, a través de hisopados rectales cultivados en medio BEAA con 6 ug/ml de vancomicina (VAN). También se estudiaron todos los aislamientos de enterococos provenientes de materiales clinicamente significativos a lo largo de los años. La resistencia a VAN fue confirmada por difusión, Etest y PCR especifica para lo genes vanA, vanB, o van C. La relación clonal fue establecida por electroforesis en campos pulsados cor cortes con la enzima Smal. El porcentaje de colonización rectal de ERV en los cortes de prevanlencia no registró un aumento significativo entre 2002 y 2007 (p > 0.05). La diversidad clonal mostró una baja tendencia hacia la diseminación intrahospitalaria de los ERV. El número de bacteriemias por ERV se mantuvo en niveles aceptables y la mayoria de las infecciones estuvieron localizadas en el tracto urinario. Concluyendo, el número de pacientes colonizados aumentó en forma sostenida pero sin diferencias significativas entre los distintos años. El número de pacientes severamente infectados con ERV hasta el momento ha sido escaso. Esto pareceria indicar que la estrategia elegida ha resultado efectiva.

Sindrome regional doloroso complejo (SRDC): reporte de un caso / Complex regional pain symdrome (CRPS): report of a case

El Síndrome Regional Doloroso Complejo (SRDC) es una enfermedad crónica caracterizada por un dolor intenso acompañado de ardor, cambios de coloración de la piel, sudoración profusa, cambios inflamatorios locales,hiperestesia cutánea y alteraciones óseas. Este síndrome es un trastorno del sistema nervioso simpático que por razones aún desconocidas permanece hiperactivo. Aquí presentamos el caso de una mujer de 28 años de edad que sufrió una fractura en el pie derecho y desarrolló SDRC tipo I y el tratamiento que le fué aplicado

Anemias nutricionales en mujeres lactantes de Costa Rica / Nutritional anemia in nursing women in Costa Rica

It is reported the prevalence, magnitude and determinant factors of nutritional anaemia in a sample of nursing women (NW), collected during the National Nutrition Survey, of Costa Rica done in 1996. Nutritional anaemia was determinate through measurements of haemoglobin, and plasma ferritin, folates, cianocobalamin and retinol. Methodologies used were cianometahaemoglobin, solid phase immunoradiometric assay, solid phase radioimmunoassay and high-pressure liquid chromatography. WHO cut-off points were used. Anaemia was present in 22.1 per cent of the women. Iron and folate deficiency were found in 48.7 and 84.2 per cent NW, respectively. The magnitude of anaemia was mild and iron and folate deficiencies were severe. Vitamin B12 and A deficiencies were 5.3 and 4.9 per cent, respectively and did not represent a public health problem in this group. Prevalent deficiency was mixed (iron and folates, 46.6 per cent) followed by exclusive folates deficiency (32 per cent). Anaemia was caused by a combined deficiency of iron and folates (61.1 per cent) and most iron deficiencies were accompanied by folates (92 per cent). The logistic regression analysis demonstrated that low socio-economic level of NW and their families was the principal factor determining the appearance of nutritional anaemia, and educative interventions to the mother are possibly recommended. In conclusion anaemia in NW is a moderate health problem of nutritional type, that is more important when severe folates and iron deficiencies are present in Costa Rica. These problems have remained constant throughout the last three decades; although recently, possibly an improvement has occurred because the prevalence of neural tube defects in the infant population has reduced, maybe due to food iron and folates fortification public health policies implementation.

Neuralgía esencial del trigémino, estudio retrospectivo de 64 casos / Esential trigeminal neuralgia: restrospective study of 64 cases

The Trigeminal Neuralgia, which is a non odontogenic pain, that takes place in the cranial-maxillofacial area, is a situation that the general dentist and tha maxillofacial surgeon, in particular, has to reconize. This study analizes 64 cases treated in period of 6 year. The epidemiologic results show several coincidences with international studies. They also show some characteristics not mentioned on the universal literature revised. The unique objective of this document is to determine the epidemiologics aspects of this desease, with respect to patients that attend spontaneously and/ or are derived from the others Services

Asimetría en el hiperparatiroidismo secundario renal: una revisión teórico analítica / Renal secundary hyperparathyroidsm: an analytical theorical review

La asimetría del hiperparatiroidismo en la insuficinecia renal crónica es muy infrecuente y está poco estudiado, algunos autores lo atribuyen a inactivación del gen supresor tumoral del cromosoma 11, actividades de oncogénes, modificación en los receptores de vitamina D y otros factores tróficos. A propósito de una revisión teórico-analítica de los archivos de anatomía patológica del Hospital Miguel Pérez Carreño (HMPC), Caracas, Venezuela período 1994-1998. Se encontró de 21.000 biopsias generales, dos casos de esta patología. Se realizó una revisión teórico-analítica para destacar los planteamientos hechos sobre dicho tópico

Limbal stem cell deficiency: concept, aetiology, clinical presentation, diagnosis and management.

Defects in renewal and repair of ocular surface as a result of limbal stem cell deficiency are now known to cause varying ocular surface morbidity including persistent photophobia, repeated and persistent surface breakdown and overt conjunctivalisation of the cornea. Ocular conditions with abnormalities of ocular surface repair include pterygium, limbal tumours, aniridia, severe scarring following burns, cicatricial pemphigoid and Stevens-Johnson Syndrome, sequelae of mustard gas exposure and Herpes simplex epithelial disease, radiation keratopathy, contact lens induced keratopathy, neuroparalytic keratitis and drug toxicity. Restoring ocular health in these eyes has traditionally been frustrating. An understanding of these intricate cell renewal and maintenance processes has spurred the evolution in recent years of new treatment methods for several blinding diseases of the anterior segment; many more exciting modalities are in the offing. However, there is inadequate awareness among ophthalmologists about the current principles of management of ocular surface disorders. The purpose of this article is to help elucidate the important principles and current treatment methods relevant to ocular surface disorders.

Corneal allograft rejection: risk factors, diagnosis, prevention, and treatment.

Recent advances in corneal graft technology, including donor tissue retrieval, storage and surgical techniques, have greatly improved the clinical outcome of corneal grafts. Despite these advances, immune mediated corneal graft rejection remains the single most important cause of corneal graft failure. Several host factors have been identified as conferring a "high risk" status to the host. These include: more than two quadrant vascularisation, with associated lymphatics, which augment the afferent and efferent arc of the immune response; herpes simplex keratitis; uveitis; silicone oil keratopathy; previous failed (rejected) grafts; "hot eyes"; young recipient age; and multiple surgical procedures at the time of grafting. Large grafts, by virtue of being closer to the host limbus, with its complement of vessels and antigen-presenting Langerhans cells, also are more susceptible to rejection. The diagnosis of graft rejection is entirely clinical and in its early stages the clinical signs could be subtle. Graft rejection is largely mediated by the major histocompatibility antigens, minor antigens and perhaps blood group ABO antigens and some cornea-specific antigens. Just as rejection is mediated by active immune mediated events, the lack of rejection (tolerance) is also sustained by active immune regulatory mechanisms. The anterior chamber associated immune deviation (ACAID) and probably, conjunctiva associated lymphoid tissue (CALT) induced mucosal tolerance, besides others, play an important role. Although graft rejection can lead to graft failure, most rejections can be readily controlled if appropriate management is commenced at the proper time. Topical steroids are the mainstay of graft rejection management. In the high-risk situations however, systemic steroids, and other immunosuppressive drugs such as cyclosporin and tacrolimus (FK506) are of proven benefit, both for treatment and prevention of rejection.

Proposición de un modelo prevención de infecciones en la práctica ortodóntica / Proposal of a model of prevention of the infections in the dental practice

Aun cuando la aparición del SIDA ha sensibilizado a la opinión pública y al personal que trabaja en el área de la salud frente al riesgo de infección, se encuentra un alto porcentaje de Ortodoncistas (según encuesta en Santiago) que en los últimos dos años no han realizado ningún tipo de capacitación en normas de prevención en sus clínicas. Sólo un 25 por ciento ha efectuado capacitación a sus auxiliares (8). Por otra parte, el 77 por ciento de los Ortodoncistas encuestados señaló no ser capaz, con anamnesis que realiza en su clínica, de lograr detectar pacientes portadores o enfermos de esta enfermedad (8). Es por esto que creemos que todo esfuerzo por parte del profesional, personnal auxiliar y de laboratorio por aplicar medidas preventivas antes, durante y después de la atención del paciente, representa una disminución del riesgo de infección. Si bien el modelo de atención presentado en el presente trabajo no constituye la única forma de aplicar criterios preventivos en la práctica ortodóntica, creemos que ayudará al profesional a tomar conciencia de la forma cómo se está llevando a cabo la prevención en su lugar de trabajo. De esta forma estaremos contribuyendo a que cada día la atención ortodóntica se realice de la forma menos riesgosa posible para el paciente, profesional, personal auxiliar y de laboratorio.

Defectos congénitos en el Hospital General de México. Frecuencia observada durante 10 años mediante el RYVEMCE / Congenital defects int eh Hospital General de Mexico. Observed frequency during 10 years by RYVEMCE

RYVEMCE, es el sistema de Registro y Vigilancia Epidemiológico de Malformaciones Congénitas Externas iniciado en 1977, que tiene como objetivo detectar y estudiar los diferentes aspectos de las malformaciones congénitas (MC) en los recién nacidos vivos y muertos. En el presente trabajo se realiza un estudio de los casos diagnosticados en el Hospital General de México de enero de 1987 a diciembre de 1996, comparándose con los resultados de los demás hostipates que participan en el RYVEMCE, durante el periodo de 1978 a 1996, encontrándose una marcada concordancia, sin embargo existen diferencias en las prevalencias para algunas MC estudiadas. Los datos revelan una elevada frecuencia de anencefalia en recién nacidos muertos, una menor frecuencia de trisomía 21 y otros datos que difieren con los datos encontrados en la literatura. Se analizan las posibles causas de estos resultados y se proponen nuevas perspectivas

Aspectos epidemiológicos y etiológicos de la hemorragia digestiva alta: estudio multicéntrico en 9 hospitales de Chile, 1980-1990 / Epidemiológicos and etiological features of upper digestive hemorrhage: multicentrico study in 9 hospitals at Chile, 1980-1990

An epidemiological survey about the incidence of upper gastrointestinal bleeding during 3 periods (1980, 1985 and 1990), was performed in 9 chilean hospitals. Its annual incidence decreased in 1990, when compared to 1980. Likewise the etiologies changes, with an increase in the incidence of duodenal ulcers and a decrease in the incidence of erosive gastritis and bleeding of unknown origin in 1990. A seasonal variation with higher bleeding rates in autumn was also recorded

Presencia de helicobacter pylori en el duodeno, antro y fundo de sujetos controles y pacientes con úlcera duodenal, úlcera gástrica, gastritis o duodenitis erosiva: análisis histológico de 357 sujetos / Presence of helicobacter pylori in duodenum, antrum and fundus in control subjects and in patients with duodenal ulcer, gastric ulcer, gastritis or erosive duodenitis: histological analysis of 357 subjects

The prevalence of helicobacter pylori infection was studied in 152 subjects with a normal upper gastrointestinal endoscopy, 125 with duodenal ulcer, 25 with gastric ulcer, 46 with erosive gastritis and 9 with erosive duodenitis. Two biopsies fron duodenum, antrum and fub¿ndus were obtained from each subject during endoscopy for histological diagnosis and Helicobacter pylori search. None of the patients with normal endoscopy and 2 percent of patients with duodenal ulcer had Helicobacter pylori in duodenal biopsies. These last patients had a significantly higher frecuency of Helicobacter pylori in the antrum (71 percent) than the rest of the studied groups. Five percent of subjects with normal endoscopy and 5 percent of those with duodenal ulcer had Helicobacter pylori in the antrum. An active gastritis was demonstrated in almost all patients with Helicobacter infection. Instestinal metaplasia occurred almost exclusively in the abscence of Helicobacter Pylori infection

Prevalencia de síntomas digestivos en mujeres adultas normales y su asociación a la litiasis biliar / Prevalence ofdigestive symptoms in normal adult women and it association with biliary lithiasis

The aim of this work was to study the prevalence of biliary diseases and digestive symptoms in normal adult women. Four hundred nineteen women were chosen; of these 145 were discarded due to previous gastrointestinal disease (20), previous gastrointestinal complaints (38) and previous cholecystectomy (85). Two hundred seventy six women were subjected to abdominal ultrasound examination; of these, 53 had cholelithiasis and in three a gallbladder cancer was suspected (and confirmed by surgery). Considering women with previous cholecystectomy, cholelithiasis and gallbladder cancer, a 33.6 per cent prevalence of biliary diseases can be inferred. An interrogation about gastrointestinal symptoms was performed to women subjected to ultrasound examinations by 2 professionals unware of ultrasound results. A high frequency of pyrosis, food intolerance and constipation was found, not observing differences between women with or without cholelithiasis. However, these last women had a higher frequency of upper abdominal pain. Both groups had also a high rate of previous surgical procedures