RESUMO
TwinsMX registry is a national research initiative in Mexico that aims to understand the complex interplay between genetics and environment in shaping physical and mental health traits among the country's population. With a multidisciplinary approach, TwinsMX aims to advance our knowledge of the genetic and environmental mechanisms underlying ethnic variations in complex traits and diseases, including behavioral, psychometric, anthropometric, metabolic, cardiovascular and mental disorders. With information gathered from over 2800 twins, this article updates the prevalence of several complex traits; and describes the advances and novel ideas we have implemented such as magnetic resonance imaging. The future expansion of the TwinsMX registry will enhance our comprehension of the intricate interplay between genetics and environment in shaping health and disease in the Mexican population. Overall, this report describes the progress in the building of a solid database that will allow the study of complex traits in the Mexican population, valuable not only for our consortium, but also for the worldwide scientific community, by providing new insights of understudied genetically admixed populations.
Assuntos
Interação Gene-Ambiente , Sistema de Registros , Humanos , México/epidemiologia , Masculino , Feminino , Adulto , Doenças em Gêmeos/genética , Doenças em Gêmeos/epidemiologia , Pessoa de Meia-Idade , Gêmeos Monozigóticos/genética , Gêmeos Dizigóticos/genética , Transtornos Mentais/genética , Transtornos Mentais/epidemiologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/epidemiologiaRESUMO
Gammadelta T lymphocytes have a heterodimeric complex formed by the association of gamma and delta chains as receptor. Proliferation of this lymphocyte population has been observed, when infection by several pathogens such as Mycobacterium tuberculosis and Plasmodium spp. occurs. The New World Monkey Aotus nancymaae has become a very good experimental model for the immunological and physiopathological study of these infectious agents. The A. nancymaae gamma-variable region was characterized from peripheral blood samples by using cDNA and genomic DNA polymerase chain reaction amplification, DNA sequencing, and dot-blot hybridization techniques. Seventeen different T-cell receptor gamma-variable (TCRGV) sequences were obtained. These sequences were distributed among TCRGV subsets 1, 2, or 3, according to human subset classification. Although no subset 4 amplification was obtained, this subset was detected by dot-blot hybridization. The presence of these 4 subsets resembles the behavior displayed by 'gammadelta-low species' (humans and mice), where high diversity among these lymphocytes can be observed. Homologies greater than 70% were found with respect to humans. Sequence convergence between human and A. nancymaae subsets 1 and 3 highlights Aotus as a promising model for studying these lymphocyte functions.
Assuntos
Aotidae/sangue , Aotidae/genética , Genes Codificadores da Cadeia gama de Receptores de Linfócitos T/fisiologia , Sequência de Aminoácidos , Animais , Evolução Molecular , Hibridização Genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
Genetic factors influence alcohol consumption and alcoholism. A number of groups have bred alcohol drinker and non drinker rat strains, but genetic determinants remain unknown. The University of Chile rat lines UChA (low drinkers) and UChB (high drinkers) display differences in the relative K(m) for NAD+ of mitochondrial aldehyde dehydrogenase (ALDH2) but no V(max) differences. The relative K(m) differences may be due to mitochondrial changes or to genetic differences coding for ALDH2. We investigated whether there are differences in the coding regions of ALDH2 cDNA in these lines and whether the Aldh2 genotype predicts the phenotype of alcohol consumption and the K(m) of ALDH2 for NAD+. Liver cDNA was prepared, and the Aldh2 transcript was amplified, cloned and sequenced. Genotyping was conducted by DNA amplification and restriction enzyme digestion. When compared to Aldh21 of Sprague-Dawley, 94% of the UChA (low drinker) rats (n = 61), presented a mutation that changes Gln67 to Arg in the mature enzyme (allele referred to as Aldh22). In UChB (high drinker) rats (n = 69), 58% presented the Aldh21 allele, while 42% presented the Gln67Arg change plus a second mutation that changed Glu479 to Lys (allele Aldh23). The Aldh22 allele was absent in high drinker rats. Rats of different Aldh2 genotypes displayed marked phenotypic differences in both ethanol consumption (g/kg/day; means +/- SE): (Aldh21/Aldh21) = 5.7 +/- 0.2, (Aldh22/Aldh22) = 0.9 +/- 0.2 and (Aldh23/Aldh23) = 4.6 +/- 0.2; and K(m)s for NAD+ of 43 +/- 3 microm, 132 +/- 13 microm and 41 +/- 2 microm, respectively (Aldh22 versus Aldh21 or Aldh23; P < 0.0001 for both phenotypes). Overall, the data show that alleles of Aldh2 strongly segregate with the phenotype of ethanol consumption and the relative K(m) for NAD+ of ALDH2. Bases mutated suggest that non drinker Aldh22 is ancestral with regard to the coding changes in either Aldh21 or Aldh23, variants which would allow ethanol consumption and may provide an evolutionary advantage by promoting calorie intake from fermented products along with carbohydrates.
Assuntos
Aldeído Desidrogenase/genética , Etanol/administração & dosagem , Mitocôndrias Hepáticas/enzimologia , Mutação , Alelos , Animais , Sequência de Bases , Clonagem Molecular , Primers do DNA , RatosRESUMO
BACKGROUND: There are no reliable markers to detect heavy drinking or as a tool to control abstinence compliance in alcoholic treatments. The Mean Corpuscular Volume (MCV), and the gammaglutamyl transpeptidase (GGT), are widely used although their predictive value is somewhat limited due to their low specificity. On the other hand, the Carbohydrate-deficient transferrin (CDT) described in the eighties is highly specific and would be of value in early detection of problem drinking. AIM: To compare the sensitivity and specificity of CDT, GGT, and MCV in order to evaluate their single and combined use as markers for detection of heavy drinking behaviour. PATIENTS AND METHODS: CDT, GGT, and MCV values were determined in blood samples from (a) alcoholics (drinking more than 100 9 alcohol/day; n = 47) and (b) healthy volunteers, teetotalers from the Church of Saints of Later Days (n = 34). At the time of sampling alcoholics were presently drinking or had been abstinent for no more than six weeks. ROC curves were used to determine the best cut-off point for each marker. RESULTS: Sensitivity was found to be similar for all three markers. Specificity was found higher for GGT (90.9%) and CDT (91.0%). The combined use of MCV, GGT and CDT, that is, when at least one of the markers is altered, was shown to detect 83% of the patients. No correlation was observed between the markers and the level of alcohol intake. CONCLUSIONS: CDT could be of value as a marker to detect heavy drinking when used with GGT and MCV values combined. CDT is particularly higher in drinking alcoholics and remains significantly high for at least six weeks after they stop drinking.
Assuntos
Consumo de Bebidas Alcoólicas/sangue , Índices de Eritrócitos , Transferrina/análise , gama-Glutamiltransferase/sangue , Adulto , Alcoolismo/sangue , Alcoolismo/diagnóstico , Biomarcadores/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Fatores de Tempo , Transferrina/análogos & derivadosRESUMO
BACKGROUND: The auto-oxidation of ethanol is likely to proceed via the initial formation of hydroxyethyl radicals (HERs), the one-electron oxidation product. In the laboratory, HERs can be generated by the Fenton reaction (H2O2+ Fe+2) in the presence of ethanol. We report studies on the binding of HERs to serum albumin, generated under Fenton and non-Fenton conditions. METHODS: The generation of HER was determined by electron paramagnetic resonance spectroscopy. The formation of ethanol-derived protein adducts was determined by 14C-ethanol incorporation into serum albumin and by the binding of antibodies raised against HER adducts. RESULTS: We report that serum albumin, used as a model protein, is an effective trapping agent of HERs. In addition, HER radicals covalently bind to albumin to form acid stable adducts. Unexpectedly, we found that under aerobic conditions, the incubation of 50 mM ethanol and phosphate buffer (which contains iron traces) in the absence of the Fenton reagent yields HER radicals as shown by electron paramagnetic resonance spectroscopy and the formation of acid stable protein adducts that are recognized by antibodies raised against HER radical adducts. CONCLUSIONS: Proteins (serum albumin used as a model) are avid trapping agents of HER. There are minimal requirements for the generation of HER, because in the presence of oxygen and a phosphate buffer that contains traces of iron, ethanol readily generates HERs. Thus, HER production is likely to occur in many tissues. The ability of proteins to bind this ethanol radical should be valuable in the diagnosis of alcohol abuse and may be relevant to some of the chronic effects of ethanol.
Assuntos
Etanol/metabolismo , Albumina Sérica/metabolismo , Animais , Radioisótopos de Carbono , Espectroscopia de Ressonância de Spin Eletrônica , Compostos Ferrosos/química , Radicais Livres , Peróxido de Hidrogênio/química , Óxidos de Nitrogênio , Oxirredução , Ligação Proteica , Piridinas , Coelhos , Marcadores de SpinRESUMO
La anemia de Fanconi es un desorden cromosómico caracterizado por una anemia aplástica familiar de carácter autosómico recesivo, que se manifiesta clínicamente con lesiones de piel, anormalidades congénitas de tipo esquelético, genitourinario y neuroocular, de baja prevalencia mundial. Se presenta un caso de anemia de Fanconi diagnósticado en un preescolar masculino de 33 meses de edad, hospitalizado en el Servicio de Pediatría del Hospital General "Patrocinio Peñuela Ruíz" de San Cristóbal. Se analizan los hallazgos clínicos y aspectos diagnósticos y terapéuticos de esta enfermedad
Assuntos
Humanos , Masculino , Pré-Escolar , Análise Química do Sangue/métodos , Anemia Aplástica/patologia , Pré-Escolar , Anemia de Fanconi/diagnóstico , Anemia de Fanconi/genética , Anemia de Fanconi/terapia , Pele/lesõesRESUMO
Se trataron discos de acrílico mediante la inmersión en clorhexidina al 0,5 por ciento y se correlacionó el tiempo de exposición a un buffer con el área de inhibición de S. mutans y C. albicans. 102 discos se trataron mediante inmersión en clorhexidina al 0,5 por ciento durante 16 minutos. Del total de discos, 51 fueron destinados para la realización del antibiograma por difusión en un medio sembrado con S. mutans y 51 en uno sembrado con C.albicans. Para la realización del antibiograma, tres discos se llevaron a cultivo, sin sumergir en el buffer, constituyendo el tiempo cero, los restantes fueron sumergidos en solución buffer y retirados en grupos de tres, a intervalos de treinta minutos, hasta completar un total de 17 períodos de observación (8 horas). En otro grupo de 16 discos tratados, se realizó el antibiograma por difusión en un medio sembrado con S. mutans. Para su realización se introdujo al cultivo, un disco sin sumergir en el buffer, el que constituyó el tiempo cero. Los restantes fueron retirados a intervalos de dos minutos, hasta completar un período de observación de treinta minutos. Durante los primeros treinta minutos, se pudo observar que el tratamiento realizado a los discos, permitió la inhibición in Vitro del desarrollo de S. mutans y C. albicans, con una correlación de 85,4 porciento entre disminución de área de inhibición y tiempo de exposición a la solución buffer. Sin embargo, después de los 30 minutos iniciales, la inhibición in vitro fue independiente de la exposición al buffer. A partir de ese momento, se logra un efecto inhibitorio del desarrollo de S. mutans, pero no de C. albicans
Assuntos
Candida albicans/efeitos dos fármacos , Clorexidina/farmacocinética , Técnicas In Vitro , Streptococcus mutans/efeitos dos fármacosRESUMO
Existe poca información respecto al esmalte aprismático, para hacer una descripción de micromorfología, se utilizaron premolares y molares sanos los que fueron observados con MEB a diferentes aumentos. Se encontró este tipo de esmalte aprismático en fosas, fisuras y en la zona cervical. Se comentan lagunas consideraciones clínicas del grabado ácido del esmalte aprismático o su eliminación previo a restauración de odontología adhesiva
Assuntos
Humanos , Dente Pré-Molar/ultraestrutura , Esmalte Dentário/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Ameloblastos/ultraestrutura , Colagem Dentária , Esmalte Dentário/química , Condicionamento Ácido do Dente/métodos , Dente Molar/ultraestruturaRESUMO
In vitro study was carry out in order to compare the microleakage of two different dentin adhesives SB-2 and SBMP in class V. One hundred class V cavities were designed in the enamel-dentin joint. After restorations they were thermocycled, loaded, stained and sectionated before the microlekage were observed. All the groups showed microleakege. The enamel walls presented better beahvior than roots walls. In roots areas were found significative higher microleakage than enamel walls. Enamel walls of Silux Plus, showed les leakage with SB2, white Z 100 worked better in roots walls with SBMP. Enamel areas of ceramic inlays were less leakage with SB2, and composites restoration always showed better sealed than ceramic inlays with both, SB2 and SBMP
Assuntos
Adesivos/análise , Infiltração Dentária , Retenção de Dentadura/métodos , Cimentos de Ionômeros de Vidro/análise , Resinas Compostas/análise , Análise do Estresse Dentário , Dentística Operatória/instrumentaçãoRESUMO
Se determina mediante MEB el comportamiento de la resina compuesta de cementación, in vitro en restauraciones cerámicas grabadas. Los resultados indican que las microporosidades fueron penetradas por las resinas de cementación. Se obtuvo un espesor promedio de la línea de ementación de 93,7 µm, presentándose mayor desajuste en las zonas marginales. En las 12 piezas estudiadas la resina de cementación mostró un contorno armónico respecto de la restauración cerámica y la pieza dentaria
Assuntos
Ligas Metalo-Cerâmicas/uso terapêutico , Cimentação , Condicionamento Ácido do Dente/métodos , Técnicas In Vitro , Resinas Compostas/uso terapêutico , Restaurações Intracoronárias , Microscopia Eletrônica de Transmissão e Varredura/estatística & dados numéricosRESUMO
Se realizó un estudio comparativo in vitro, entre la técnica químico-mecánica (Caridex) y la técnica convencional en la remoción de caries radiculares. Se evaluó tanto clínica como histológicamente la eficiencia de estos métodos de eliminación de caries. Se observó que ambos procedimientos fueron eficientes en la remoción de caries radicular. La dentina libre de caries, remanente despúes del tratamiento con Caridex, se presenta diferente a la cavidad dentinaria fresada
Assuntos
Aminobutiratos/uso terapêutico , Dentina/química , Técnicas In Vitro , Cárie Radicular/terapia , Polpa Dentária/ultraestrutura , Dentina/ultraestrutura , Infiltração Dentária , Microscopia de Polarização , Porosidade/efeitos dos fármacos , Cárie Radicular/patologia , Resultado do TratamentoRESUMO
A study was made of 71 patients treated by means of surgery in the Department of Periodontology of the Provincial Stomatological Clinic of Santiago de Cuba during the September-November 1983 quarter. Gum samples were taken and preserved in 10% formalin. Forty-eight hours later they were processed in the Department of Pathological Anatomy of the Saturnino Lora Clinica-surgical Hospital, in order to observe the intensity of inflammation and the number of cells, classified as scarce, moderate and severe. Also, the epithelial changes were analyzed. The results achieved reveal that lymphocytes and plasmocytes were observed in a larger percent, whereas acanthosis was the most frequent change in the epithelium.
Assuntos
Doenças Periodontais/patologia , Acantócitos/análise , Adolescente , Adulto , Feminino , Humanos , Contagem de Leucócitos , Linfócitos/análise , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/imunologia , Plasmócitos/análiseRESUMO
A microbiologic study was carried out in 39 patients with periodontal affections, who were surgically treated. A formulary was drawn up for the collection of the following data: age, sex, criteria of Russell periodontal index and microbiologic results. The contents of the periodontal pocket was collected at the time of the surgical procedure, and settled in assay tubes with culture medium to provide bacterial growth. The highest percentage of microorganisms were those of genus Peptostreptococci, and most common severity was caused by parodontitis.
Assuntos
Bolsa Periodontal/microbiologia , Periodontite/microbiologia , Adulto , Feminino , Humanos , Masculino , Peptostreptococcus/isolamento & purificação , Doenças Periodontais/microbiologiaRESUMO
Se efectuó el estudio de las propiedades físicas de 2 aleaciones Plata-Paladio cuyo peso específico fluctuó entre 10-10,5 gr/cm3. Su dureza superficial osciló entre 70-91,2 Rockwell B. Los resultados cualitativos y cuantitativos indicaron la presencia de Ag(65-80%), Pd(15-20%), Zn(3-4%) y Ca(1-1,5%_ en ambas aleaciones, sólo presentó Cu(8-12%) una de ellas. Desde un punto de vista cristalográfico estas aleaciones están compuestas básicamente de un sistema Ag- Pd formando soluciones sólidas de fases heterogéneas