Resultados a siete años de la cirugía de reemplazo valvular aórtico en mayores de 80 años / Seven-year results of aortic valve replacement surgery in patients over 80 years of age

Resumen Objetivo: Describir las características clínicas y los resultados operatorios y a siete años del reemplazo valvular aórtico en una cohorte de pacientes mayores de 80 años. Materiales y métodos: Estudio descriptivo retrospectivo de 75 pacientes consecutivos mayores de 80 años, intervenidos de reemplazo valvular aórtico exclusivo entre 2007 y 2019 en el Hospital Guillermo Grant Benavente. Se estudian sus características demográficas, clínicas, ecocardiográficas, riesgo operatorio, cirugías, complicaciones y mortalidad operatoria y supervivencia alejada hasta el 15 de marzo 2021. Resultados: La edad media de la cohorte fue 83,05 ± 2,9 años (rango 80-95) y 43 pacientes eran mujeres (57,3%). La lesión valvular predominante fue la estenosis aórtica (89,3%). 10 pacientes tenían enfermedad coronaria asociada (13,3%) y 2 endocarditis activa. El riesgo de mortalidad operatoria calculado por EuroSCORE aditivo, logístico, II y STS score fue 7,58 ± 1,8; 9,88 ± 6,5%; 3,72 ± 3,5% y 4,27 ± 3,2%, respectivamente. Se utilizó prótesis biológica en 70 (92%) pacientes. Hubo 29 complicaciones operatorias y fallecieron 11 (14,7%) pacientes. El seguimiento promedio fue 7,1 años (rango 2-14), durante el cual fallecen 28 pacientes. La supervivencia a uno, tres y cinco años fue 82, 76, 66 y 48% respectivamente. Conclusiones: La cirugía de reemplazo valvular aórtico en octogenarios en nuestro medio es un procedimiento poco frecuente. La mortalidad observada fue mayor que la estimada por las escalas de riesgo. El reemplazo valvular quirúrgico es una alternativa de tratamiento de la enfermedad de la válvula aórtica en pacientes seleccionados. Se deben evaluar estrategias para mejorar los resultados.

Abstract Objective: To describe the clinical characteristics and operative and 7-year results of aortic valve replacement in a cohort of patients older than 80 years. Materials and methods: Retrospective descriptive study of 75 consecutive patients older than 80 years of age who underwent exclusive aortic valve replacement between 2007 and 2019 at the Guillermo Grant Benavente Hospital. Demographic, clinical, echocardiographic characteristics, operative risk, surgeries, complications and operative mortality and long-term survival until March 15, 2021 are studied. Results: The mean age of the cohort was 83.05 ± 2.9 years (range 80-95) and 43 patients were women (57.3%). The predominant valve lesion was aortic stenosis (89.3%). Ten patients had an associated coronary artery disease (13.3%) and 2 had active endocarditis. The risk of operative mortality calculated by EuroSCORE additive, logistic, II and STS score was 7.58 ± 1.8; 9.88 ± 6.5%; 3.72 ± 3.5% and 4.27 ± 3.2%, respectively. A biological prosthesis was used in 70 (92%) patients. There were 31 operative complications and 11 (14.7%) patients died. The mean follow-up was 7.1 years (range 2-14), during which 28 patients died. Survival at 1, 3, and 5 years was 82, 76, 66 and 48%, respectively. Conclusions: Aortic valve replacement surgery in octogenarians in our setting is a rare procedure. The observed mortality was higher than that estimated by the risk scales. Surgical valve replacement is an alternative treatment for aortic valve disease in selected patients. Strategies to improve results should be evaluated.

Variablilidad de la presión arterial, hipertensión arterial nocturna y su asociación con tabaquismo / Blood pressure variability, nocturnal hypertension and its association with smoking / Variabilidade da pressão arterial, hipertensão arterial noturna e sua associação com o tabagismo

Resumen: Introducción: La hipertensión arterial y el tabaquismo son factores de riesgo independientes para el desarrollo de eventos cardiovasculares. El consumo de tabaco determina una elevación aguda de la presión arterial por acción del sistema simpático. Sin embargo los efectos a largo plazo son contradictorios. El aumento de la variabilidad de la presión arterial y la presencia de hipertensión arterial nocturna se asocia con eventos cardiovasculares adversos independientemente de los niveles de presión arterial. Objetivos: Evaluar la asociación entre tabaquismo e hipertensión arterial diurna, nocturna y variabilidad. Material y Métodos: Estudio analítico, observacional, transversal, multicéntrico, que incluye pacientes hipertensos mayores de 18 años con monitoreo ambulatorio de la presión arterial (MAPA). Resultados: Se incluyeron 391 pacientes, siendo 14.6% fumadores. Se encontraron cifras de presión arterial diurna sistólica y diastólica más elevadas en pacientes tabaquistas (p=0.204, p=0.087, respectivamente). Se observó una asociación significativa entre la hipertensión arterial nocturna y la presencia de diabetes mellitus e índice de masa corporal aumentado. No se encontró asociación entre el consumo de tabaco y los distintos patrones de variabilidad, así como tampoco con la hipertensión arterial nocturna. Conclusiones: El grupo de pacientes fumadores presentó una tendencia a cifras de presión arterial media diurna sistólica y diastólica más elevadas que los no fumadores, lo que podría sugerir que el tabaquismo incide en el control de cifras de presión arterial.

Abstract: Introduction: Hypertension and smoking are independent risk factors for the development of cardiovascular events. Tobacco use causes an acute elevation of blood pressure due to the action of the sympathetic system. However, the long-term effects are contradictory. Increased variability in blood pressure and the presence of nocturnal arterial hypertension are associated with adverse cardiovascular events regardless of blood pressure levels. Objectives: To evaluate the association between smoking and daytime and nighttime arterial hypertension and variability. Material and Methods: Analytical, observational, cross-sectional, multicenter study, which includes hypertensive patients over 18 years of age with ambulatory blood pressure monitoring (ABPM). Results: 391 patients were included, being 14.6% smokers. Higher levels of systolic and diastolic daytime blood pressure were found in smoking patients (p = 0.204, p = 0.087, respectively). A significant association was observed between nocturnal arterial hypertension and the presence of diabetes mellitus and increased body mass index. No association was found between tobacco consumption and the different patterns of variability, as well as with nocturnal arterial hypertension. Conclusions: The group of smoking patients showed a trend towards higher mean daytime systolic and diastolic blood pressure figures than non-smokers, which could suggest that smoking affects the control of blood pressure numbers.

Resumo: Introdução: Hipertensão e tabagismo são fatores de risco independentes para o desenvolvimento de eventos cardiovasculares. O uso do tabaco provoca elevação aguda da pressão arterial devido à ação do sistema simpático. No entanto, os efeitos de longo prazo são contraditórios. O aumento da variabilidade da pressão arterial e a presença de hipertensão arterial noturna estão associados a eventos cardiovasculares adversos, independentemente dos níveis de pressão arterial. Objetivos: Avaliar a associação entre tabagismo e hipertensão arterial diurna e noturna e variabilidade. Materiai e Métodos: Estudo analítico, observacional, transversal, multicêntrico, que inclui hipertensos maiores de 18 anos com monitorização ambulatorial da pressão arterial (MAPA). Resultados: Foram incluídos 391 pacientes, sendo 14,6% tabagistas. Níveis mais elevados de pressão arterial diurna sistólica e diastólica foram encontrados em pacientes fumantes (p = 0,204, p = 0,087, respectivamente). Foi observada associação significativa entre hipertensão arterial noturna e presença de diabetes mellitus e aumento do índice de massa corporal. Não foi encontrada associação entre o consumo de tabaco e os diferentes padrões de variabilidade, bem como com a hipertensão arterial noturna. Conclusões: O grupo de pacientes fumantes apresentou tendência a valores médios de pressão arterial sistólica e diastólica mais elevados do que os não fumantes, o que pode sugerir que o tabagismo afeta o controle dos valores da pressão arterial.

Cigarrillo electrónico y otros sistemas electrónicos de liberación de nicotina: revisión de evidencias sobre un tema controversial / Electronic cigarette and other electronic nicotine delivery systems: a review of evidence on a controversial topic / Cigarro eletrônico e outros sistemas eletrônicos de liberação de nicotina: revisão de evidências sobre um tema controverso

Resumen: Introducción: los cigarrillos electrónicos (CE) son sistemas que liberan aerosol conteniendo nicotina y otras sustancias. Desde su aparición han generado una gran controversia en la comunidad científica dedicada al control de tabaco, existiendo evidencias que los posicionan como una alternativa de tratamiento para la cesación tabáquica y otros estudios que muestran sus daños a la salud, así como convertirlos en la puerta de entrada a los jóvenes a la adicción a nicotina. Objetivo: recopilar evidencia disponible sobre CE con referencia a componentes, riesgos para la salud, cesación de tabaquismo, impacto poblacional y aspectos normativos y regulatorios. Método: revisión narrativa. Se realizó búsqueda bibliográfica en bases PubMed, MEDLINE, SCOPUS, Redalyc, SciELO, LiLACS, Dialnet, ScienceDirect, así como en documentos de la Organización Mundial de la Salud, sociedades científicas, sitios web dedicados a consumidores y legislación nacional e internacional. Resultados: se revisaron 130 documentos, de los cuales se toman los 63 más relevantes. Existen evidencias científicas sobre contenidos tóxicos y carcinógenos en líquidos y aerosoles de los CE, así como de daño a la salud cardiovascular y respiratoria. Se presentan estudios controversiales sobre su eficacia para dejar de fumar. Se presenta evidencia acerca de cómo los CE impactan negativamente en la iniciación de jóvenes al consumo y en la recaída de exfumadores. Se analiza la normativa nacional e internacional para regular los CE. Conclusiones: los profesionales de la salud no deben aconsejar el uso de CE, dado que no son seguros y exponen a los consumidores y a la población en general de los efectos deletéreos directos e indirectos de los CE.

Summary: Introduction: e-cigarettes are systems that produce and release aerosol that contains nicotine and other substances. They have been controversial in the scientific community that works on tobacco control ever since they were created. There is evidence suggesting they are an alternative therapy for tobacco cessation and other studies prove they are harmful to health, and they end up being the door that welcomes young people to the world of nicotine addiction. Objective: to collect evidence on e-cigarette in connection with: components, risks to the health, tobacco cessation, impact on the population and normative and regulatory aspects. Method: Review of the literature. Bibliographic search on PubMed, MEDLINE, SCOPUS, Redalyc, Scielo, LiLACS, Dialnet, ScienceDirect, as well as in other documents of the World Health Organization, scientific societies, websites dedicated to consumers and the national and international laws. Results: 130 documents were reviewed, and the 63 most relevant ones served as the grounds for the study. There is scientific evidence on the toxic and carcinogenic content of liquids and aerosols of e-cigarettes, as well as on their negative effect on cardiovascular and respiratory health. We present controversial studies on its effectiveness to give up smoking, evidence on how e-cigarettes have a negative influence on the initiation of consumption by the young and on ex-smokers relapse. The study also analyses the national and international norms regulating e-cigarettes. Conclusions: health professionals must not recommend the use of e-cigarettes, since they are not safe and expose consumers and the general population to its direct and indirect harmful effects.

Resumo: Introdução: os cigarros eletrônicos (CE) são sistemas que liberam aerossol contendo nicotina e outras substâncias. Desde seu surgimento geraram uma grande controvérsia na comunidade científica dedicada ao controle do tabaco, existindo evidências que os colocam como uma alternativa de tratamento para a cessação do tabagismo e outros estudos que mostram seus danos à saúde, e como se transformam na porta de entrada dos jovens a adição a nicotina. Objetivo: recuperar a evidência disponível sobre CE com referência a: componentes, riscos para a saúde, cessação de tabagismo, impacto populacional e aspectos normativos e regulamentares. Método: revisão narrativa. Fez-se uma pesquisa bibliográfica nas bases PubMed, MEDLINE, SCOPUS, Redalyc, Scielo, LiLACS, Dialnet, ScienceDirect, e também em publicações da Organização Mundial da Saúde, sociedades científicas, sites web dedicados a consumidores e legislação nacional e internacional. Resultados: foram selecionados os 63 documentos mais relevantes dos 130 recuperados. Existem evidências científicas sobre conteúdos tóxicos e carcinogênicos em líquidos e aerossóis dos CE e também dos danos à saúde cardiovascular e respiratória. Apresentam-se estudos controversos sobre sua eficácia para apoiar o abandono do hábito de fumar e evidência de como os CE têm um impacto negativo na iniciação de jovens ao consumo e na recaída de ex- fumantes. Faz-se uma análise das normas nacionais e internacionais para regular os CE. Conclusões: os profissionais de saúde não devem aconselhar o uso de CE por não ser seguros e por que expõem os consumidores e a população em geral aos efeitos deletérios diretos e indiretos de seu uso.

Cesación tabáquica en la salud cardiovascular / Smoking cessation in cardiovascular health

Resumen: La Organización Mundial de la Salud ha determinado que las enfermedades no transmisibles (ENT) constituyen uno de los mayores desafíos del presente siglo, ya que representan el 71% de las muertes que se registran en el mundo. El tabaquismo se considera uno de los principales factores de riesgo modificables que afecta a las ENT. Existe amplia evidencia que relaciona el tabaco con las enfermedades cardiovasculares, en particular con la cardiopatía isquémica. Las Guías de Prevención Cardiovascular de la Sociedad Europea de Cardiología del año 2016 establecen como recomendación clase I, nivel de evidencia A, el dejar de fumar. El efecto de la nicotina genera una fuerte adicción que desencadena un síndrome de abstinencia al intentar el abandono del consumo de tabaco. Por lo tanto, resulta necesario estar familiarizado con las estrategias para el tratamiento de la adicción al tabaco, que comprenden: intervención mínima, recursos cognitivo-conductuales y tratamiento farmacológico como terapia de sustitución nicotínica, bupropión y vareniclina. Hasta el momento no se cuenta con la suficiente evidencia científica para recomendar los dispositivos electrónicos.

Summary: The World Health Organization has determined that Non- communicable Diseases are one of the greatest challenges of this century as they represent 71% of the deaths that occur in the world. Smoking is considered one of the main modifiable risk factors that affect Non-communicable Diseases. There is ample evidence linking tobacco with cardiovascular diseases, particularly with ischemic heart disease. The guidelines for Cardiovascular Prevention of the European Society of Cardiology of 2016, establish as recommendation class I, level of evidence A, the cessation of smoking. The effect of nicotine generates a strong addiction that triggers an abstinence syndrome when trying to quit smoking. Therefore, it is necessary to be familiar with the strategies for the treatment of tobacco addiction that include: minimal intervention, cognitive-behavioral resources and pharmacological treatment such as nicotinic substitution therapy, bupropion and varenicline. So far, there is not enough scientific evidence to recommend electronic devices.

Estudio comparativo de prevalencia del gen de la ECA en muestras de diabéticos y población general / Comparative study on the prevalence of the Angiostatin-converting enzyme gene in diabetic patients and general population samples

Introducción: previamente se ha demostrado que los pacientes diabéticos poseen una incidencia aumentada de patologías micro y macrovasculares. En la exploración de posibles determinantesaparece como candidato atractivo el gen de la enzima convertidora de angiotensina (ECA) el cual presenta de acuerdo al polimorfismo InDel existente, un aumento de la concentración enzimática en sangre asociado a enfermedades vasculares. Objetivo: se plantearon como objetivos establecer la prevalencia del polimorfismo del gen de la ECA, en pacientes diabéticos y comparar las frecuencias con las halladas para la población general demanera de revelar si existe asociación del locus con la diabetes mellitus.Material y método: la población estudiada consistió en 131 individuos con diagnóstico certero de diabetes según criterios de la American Diabetes Association. Se hallaron las frecuencias génicas y genotípicas del polimorfismo InDel del gen de la ECA mediante la técnica de reacción en cadena dela polimerasa (PCR). Resultados: no se encontraron diferencias significativas en la prevalencia del marcador estudiadoentre diabéticos y la población general. Las frecuencias génicas halladas en diabéticos fueron 0,435 para alelo I y 0,565 para alelo D versus 0,440 alelo I y 0,560 alelo D en la población general.Discusión: en suma, este marcador es un factor de riesgo que no está asociado a la diabetes en sí misma, sino que la relación entre este gen y las complicaciones vasculares serían las mismas para diabéticos que para la población general.

Introduction: we have previously demonstrated that diabetic patients have an increased incidence of micro and macrovascular pathologies. Upon exploration of possible determining factors, the ACE gene appears as an attractive factor, since it presents, according to the existing InDelpolymorphism, an increase of the enzyme concentration in blood associated to vascular diseases.Objective: to establish the prevalence of polymorphism of the ACE gene in diabetic patients, and to compare thefrequencies with those found in the general population, in order to find out whether there is a relationship betweenlocus and diabetes mellitus. Method: the population studied consisted of 131 individuals with a certain diagnosis of diabetes, according to criteria of the American Diabetes Population. We determined InDel polymorhism´s genic and genotypic frequencies in the ACE gene through the polymerase chain reaction (PCR). Results: we failed to find meaningful differences in theprevalence of the marker studied between diabetic patients and the general population. Discussion: to sum up, the present marker is a risk factor that is not associated to diabetes itself; hence the relationship between this gene and vascular complications would be the same in diabetic patients and the general population.

Introdução: está demonstrado que os pacientes diabéticos apresentam uma maior incidência de patologias microy macrovasculares. Na pesquisa de possíveis determinantes aparece como candidato possível o gen da ECA queapresenta, de acordo ao polimorfismo Índio existente, um aumento da concentração enzimática no sangue associado a patologias vasculares.Objetivo: estabelecer a prevalência do polimorfismo do gen da enzima convertidora de angiotensina (ECA), empacientes diabéticos e comparar as freqüências encontradas com as determinadas para a população em geral para verificar a existência de uma associação do lócus com a diabetes mellitus. Material e método: a população estudada estava composta por 131 indivíduos com diagnóstico confirmadode diabetes de acordo com os critérios da American Diabetes Association. As freqüências gênicas e genotípicas do polimorfismo InDel do gen da ECA foramdeterminadas pela técnica de reação em cadeia da polimerase (PCR). Resultados: nao se encontraram diferenças significativas na prevalên-cia do marcador estudado entre diabéticose a população em geral. As freqüências gênicas encontradas em diabéticos foram 0,435 para alelo I e 0,565para alelo D e, 0,440 alelo I e 0,560 alelo D na população em geral.Discussão: este marcador é um fator de risco que não está associado à diabetes, porém a relação entre este gen e as complicações vasculares seria a mesma para diabéticos que para a população em geral.

Paladar Hendido, Tratamiento quirúrgico, Injerto óseo combinado con plasma rico en plaquetas

Hace unos años en las décadas 40 y 50 del siglo pasado se realizaron estudios, debido a que se observó hipodesarrollo del tercio medio de la cara como consecuencia del tratamiento quirúrgico en épocas tempranas de la vida del paciente con paladar fisurado. Cirujanos odontólogos comenzaron a utilizar el injerto óseo para conseguir la integridad anatómica del arco alveolar y así facilitar su desarrollo, la erupción dentaria y las funciones intermaxilares. Estas intervenciones son muy cruentas por la toma del transplante en zonas como la tibia, costilla e iliom. En la actualidad existen técnicas menos cruentas y agresivas como la que utiliza el plasma rico en plaquetas mezclado con hueso autógeno medular. Se hace el reporte de un caso.

Some years ago in the 40 and 50 decades of last century were carried out studies, because little development of the half third of the face was observed as consequence of the surgical treatment in early times of the patient’s life with cleft palate. Surgeons dentists began to use bone graft to get the anatomical integrity of the alveolar arch and this way to facilitate their development, the eruption would jag and the intermaxillary’s functions. These interventions are very bloody for the taking of the transplant in areas like the lukewarm one, rib and ilium. At the present time less bloody and aggressive techniques exist as the one that uses the platelet rich plasma in blended platelet with medullary autogenous bone. The repot of a case is made.

Anos a nas décadas 40 e 50 dos estudos do último século foram feitos, porque o hipo-desarrolho de terceiros meios da cara foi observado em conseqüência do tratamento cirúrgico em épocas adiantadas da vida do paciente com paladar fisurado. Os cirurgião dentistas começou a usar o enxerto ósseo poder a integridade anatômica do arco alveolar e facilitar assim seu desenvolvimento, o erupção dental e os intermaxilares das funções. Estes intervenção são muito sangrentos fazer exame do transplante nas zonas como o tibia, reforço e iliom. No tempo atual existem mais técnicas menos sangrentas e agressivas como qual usa o plasma rico nos plaquetas misturado com o osso medular autógeno. O relatório acontece com um caso.

Mecanismos celulares y moleculares de la neurotoxicidad por plomo

resumen está disponible en el texto completo

Abstract: Lead, a heavy metal, has been used by humans for many technological aims, a fact that has determined its actual widespread distribution. Although various actions have been taken to diminish the use and distribution of lead in the environment, it remains a significant health problem. The evolution of technological processes applied in the industry has followed economic interest. Its only in recent times that criteria related to health and ecology have been considered while designing new industries. Particularly susceptible groups are children and workers involved in mining, metallurgy, paint manufacturing and battery recycling. The communities living in areas where those industries are settled have also a higher lead exposure risk. Its high biological toxicity has determined lead to become one of the most significant environmental contaminants with pathogenic potential for humans. The toxic mechanism of lead is essentially due to its capability to substitute other polyvalent cations (particularly divalent cations such as calcium and zinc) into the molecular machinery of living organisms. Thanks to its ionic structure, lead establishes very favorable interactions, usually with higher affinity, with chemical groups that normally coordinate divalent cations in proteins. The coordination of cations in proteins is usually achieved by negatively charged acidic residues. These residues establish ionic interactions with the positively charged ion, resulting in a change in the structure and electric charge of the protein. These interactions determine that lead may affect different biologically significant processes, including metal transporting proteins, ionic channels, cell adhesion molecules, diverse enzymes which have metallic cofactors, signaling molecules such as calmodulin and protein kinase C and DNA binding proteins, among other molecular targets. Lead interactions with the coordinating amino acid residues in proteins may induce an abnormal conformational configuration of proteins, as compared to the conformational structure acquired when interacting with commonly active cations, thus significantly altering its functional properties in the very complex molecular machinery. Among the biologically active sites usually occupied by lead, those related to calcium seem to have the most significant pathological importance for lead toxicity due to their widespread distribution and highly significant functional relevance for the normal cell function. Two of the principal calcium binding motifs in proteins, the EF-hand motif and the C2 motif, have an intrinsic high affinity for lead. In the case of EF-hand motifs, calmodulin is one of the most remarkable targets for lead due its importance in regulating cellular processes, being activated by lead at lower concentrations than required for calcium and displaying an abnormal activity. The C2 motif is expressed mainly in calcium dependent membrane associated proteins such as protein kinase C (PKC) or synaptotagmin. The principal characteristic in these motifs is an electrical change in the protein after the calcium binding, allowing its interaction with biological membranes. In synaptotagmin, according with the electrical characteristics of lead, the interaction of the complex lead-synaptotagmin with biological membranes is similar to the interaction calcium-synaptotagmin with membranes, which is eminently electrical. Hence, the conformation of this complex is probably different to the conformation with calcium, fact evidenced by the failure of lead-synaptotagmin to interact with other proteins of the exocitic machinery. In relation to lead neurotoxicity, membrane ionic channels seem to be among the most relevant molecular targets of lead. In particular, calcium and potassium channel function may be significantly impaired by lead, affecting the activation of calcium activated potassium channels, the inactivation process of calcium channels, and the ionic conductance of calcium channels. As occurs with other heavy metals, lead is capable of blocking the calcium channel, probably at the selectivity filter. The high affinity lead binding to the acidic residues of the filter provokes a slow flux of the metal trough the channel pore, blocking the calcium conductance. The regulation of ionic channels will be significantly altered also. Calmodulin is a common calcium sensing protein for many ionic channels and its alteration by lead could affect the channel operation. Abnormal functioning of regulatory and signaling proteins such as calmodulin, protein kinase C and synaptotagmins, which normally require calcium for its activity, may also display an abnormal functioning, thus determining a widespread metabolic influence of lead poisoning. Lead distributes evenly into the cell thus reaching intracellular organelles, including the endoplasmic reticulum, mitochondria and the cell nucleus. This results in significant alterations of intracellular calcium metabolism and regulation due in part to the malfunctioning of calcium channels and ionic pumps in plasma membrane, endoplasmic reticulum and mitochondria. Inadequate energy generation due to mitochondrial damage and malfunctioning in cation dependent enzymes, alterations in protein folding due to the direct binding of lead to calcium activated reticular chaperones, or indirectly, altering the intrareticular calcium levels, and the disruption of the structure of DNA binding motifs such as zinc fingers, among others, promotes alterations in gene expression and DNA reparation. Lead poisoning is one of the most important chronic environmental illnesses affecting children in modern life. Developing central nervous system is particularly susceptible to lead toxicity. At critical times in development, lead may have a disorganizing influence with long-lasting effects which may continue into teenage and beyond. Mechanisms originating this disorganizing influence in the central nervous system are a consequence of the interaction of lead with various targets as previously described; alterations of cell molecular machinery, at the systems level induce excitotoxic phenomena, interferes with neurotransmission at neurotransmitter synthesis, release and receptor activation levels, alters intracellular signaling and produce cell membrane peroxidative damage. Compared to adult lead poisoning, pediatric lead is most common and its effects may occur at reduced blood levels with subclinical symptoms; thus a high index of suspicion is necessary for physicians when dealing with pediatric patients. Long-term effects of lead may produce cognitive and motor impairment, with behavioral alterations. The particular vulnerability of the immature nervous system to the lead poisoning is probably due to the fact that in this stage of development the establishment of appropriate neural networks is highly dependent on the synaptic activity, which in turn could be altered by lead. Lead poisoning has been considered as a potential co-factor in complex neuropsychological alterations such as schizophrenia. In this sense it is worth to note the possibility that the physical and psychic symptoms of Vincent Van Gogh may have been due to chronic lead poisoning. The following are among the clinical symptoms described by Van Gogh in his autographed letters: initial debilitation, stomatitis with loss of teeth, recurring abdominal pains, anemia (with a "plumbic" skin tone), neuropathy of the radial and saturnine encephalopathy, including epileptic crises, progressive character changes and periods of delirium, all of which meet present criteria for diagnosis of Organic Mental Disorder due to cerebral lesion or somatic illness, and Organic Character Disorder (DSM-IV-R). Apha-thujone, found in absinthe and in many popular herbal medicines, may also have contributed to Van Gogh symptoms since he was a well-known absynthe drinker. Many countries, including Mexico, have implemented politics aimed to eliminate lead from the majority of their industrial processes. This has been carried out with considerable effort, and in some cases, with open confrontations between the scientific community and industrial sector. Although there have been actually significant advances to eliminate lead from many products (gasoline, painting manufacturing, etc.), lead is not degradable, thence once it is released in the environment it remains there for long periods of time. This implies that we should have to deal with lead poisoning in the years to come and to be aware of this diagnostic possibility in any suspicious case. This review is centered in the description of the molecular mechanisms of lead toxicity and its repercussion in the cellular excitability and central nervous system function.

Asociación entre hiperhomocisteinemia, cardiopatía isquémica y diabetes tipo 2

La hiperhomocisteinemia es considerada como un factor de riesgo para las enfermedades vasculares en la población general. Sin embargo, su rol en el desarrollo de la cardiopatía isquémica (CI) no ha sido totalmente dilucidado. El objetivo fue determinar, si existe, en primera instancia una asociación entre la cardiopatía isquémica y los niveles elevados de homocisteína en plasma y posteriormente investigar la posible asociación entre la hiperhomocisteinemia y la diabetes mellitus tipo 2. Se analizó la información de 204 pacientes atendidos en consultorios dependientes del CASMU con una edad promedio de 61,2±10,8 años. Se siguieron los criterios de las guías de Task Force y ADA para el diagnóstico de cardiopatía isquémica y diabetes, respectivamente. Se tomaron valores entre 5-15 µmoles/lt de homocisteína plasmática como normales. Los pacientes fueron clasificados en dos grupos: con cardiopatía isquémica (CCI) y sin cardiopatía isquémica (SCI). En las comparaciones realizadas entre los grupos se observaron diferencias significativas en la distribución de los niveles de homocisteína plasmática entre los individuos CCI y SCI (p<0,001). A su vez, se observó una asociación entre los valores de hiperhomocisteinemia y la CI (OR=2,66). Por otra parte, la ausencia de diferencias significativas entre diabéticos y no diabéticos con CI estaría indicando que la diabetes y la hiperhomocisteinemia serían dos características genéticas independientes o -dicho de otra forma- el hecho de ser diabético no altera la asociación entre la hiperhomocisteinemia y la cardiopatía isquémica.

A high plasmatic level of homocysteine is considered as a risk factor to vascular disease in the general population. However, the role of hyperhomocysteinaemia in the ischaemic heart disease development is not totally elucidated. The aim of our study was to determine in fist place, if in our sample there is an association between homocysteine levels and ischaemic heart disease and subsequently to investigate a possible association of hyperhomocysteinaemia to the presence of diabetes mellitus type 2. We analyzed the information of 204 patients attending to private health centers (depending from CASMU). All patients (61,2 ± 10,8 year olds average) were diagnosed as diabetic type 2 and ischaemic heart disease according to the ADA and Task Force guides criteria respectively. We took 5-15 µmol/l homocysteine plasmatic value as normal. The patients were classified in two groups: with (CCI) and without ischaemic heart disease (SCI). We observed statistical significant differences in the distribution of homocysteine plasmatic levels between: CCI and SCI (p<0,001). We also observed an association between hyperhomocysteinaemia and CI (OR=2,66). In the other hand, non-significant statistical differences between diabetic and non diabetics patient with CI would be indicate that that hyperhomocysteinaemia and diabetes are two independent genetics factors; the diabetes condition do not alter the association between hyperhomocisteinaemia and CI.

Paladar hendido. Tratamiento quirúrgico: reporte de un caso / Cleft palate. Surgical treatment: report of a case

Hace unos doscientos años se practicaron las primeras intervenciones del paladar, las cuales fracasaron por las cruentas disecciones y la poca irrigación de los colgajos que provocaban cicatrices con grandes retracciones. Al pasar los años, cirujanos famosos con sus estudios y tÚcnicas ayudaron a formar la metodologÝa usada en la actualidad. Se presenta una compilación y comentarios de mÚtodos utilizados en el tratamiento quirúrgico del paladar fisurado y se hace el reporte de un caso

Características morfológicas y electrofisiológicas de las neuronas del ganglio vestibular en cultivo / Morphologic and electrophysiologic characteristics of cultured vestibular ganglia neurons

Vestibular afferent neurons have been classified on the basis of their spontaneous activity as regular and irregular; this has been attributed to their synaptic input, but it remains to be defined the participation of some intrinsical properties of the afferent neurons in the determination of their discharge pattern. In this work, we have developed tissue cultures of the rat vestibular ganglia. Isolated cells were plated using poly-D-lysine or collagen as substrates and L-15 or Neurobasal as culture media. After 48 hrs cells in the four experimental conditions give forth neurites of variable longitude. By using antibodies against the neurofilaments 160 kDa the cell structure was studied. Monopolar (30.6), bipolar (63.9) and multipolar (5.5) cells were found. By using the voltage and current clamp procedures the voltage dependence and kinetics of the tetrodotoxin sensitive Na+ current was fully characterized. Cultured cells were shown to generate action potentials under electrical stimulation, and they were capable of repetitive spike discharge under the influence of 4-aminopyridine. These results demonstrate that tissue cultures constitute an excellent system to study the intrinsical properties of vestibular afferent neurons.

Hernia diafragmática en esofagectomía transhiatal / Diaphragmatic hernia in transhiatal esophagectomy

La hernia diafragmática tras una esofagectomía transhatial es una complicación grave, especialmente cuando el diagnóstico es tardío. Presentamos el caso de una paciente que desarrolló una obstrucción completa del intestino delgado por una hernia diafragmática que se presentó tras una esofagectomía transhiatal. Paciente de 55 años, sexo femenino, que presentaba un carcinoma escamoso del tercio distal del esófago. Se realizó esofagectomía transhatial, con gatroplastía tubular transmediastínica posterior. En el 5º día postoperatorio presenta dolor torácico, vómitos, dificultad respiratoria y polipnea. El examen físico demostró clínica de derrame pleural en el hemitórax derecho. La radiografía de tórax mostró imagen de ocupación pleural en el hemitórax derecho y la radiología contrastada gastrointestinal mostró un asa de intestino delgado en hemitórax izquierdo. En la laparotomía exploradora se comprueba hernia a través del orificio hiatal ampliado y en hemitórax izquierdo con estrangulación y perforación de una asa yeyunal. Se realizó reducción del contenido herniario y enterorrafia. Evolución tórpidamente y egresa del hospital en buenas condiciones a los 57 días del postoperatorio

Labio hendido, corrección quirúrgica: reporte de un caso / Cleft lip, surgical correction: report of a case

Hace aproximadamente quinientos años comenzó el tratamiento quirúrgico del labio hendido con diseños sencillos en las técnicas, las cuales traían como consecuencia que en la cicatrización estaba presente la retracción y deformación del labio en forma de silbido. Con el transcurso del tiempo fueron apareciendo métodos hechos por diferentes cirujanos cuyos diseños comenzaron a dividir la incisión en segmentos para compensar la retracción. Presentamos una compilación y comentarios de algunos de ellos