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Introducción: Los casos de tiroides ectópica localizados en la base de la lengua son anormalidades congénitas raras y difíciles de diagnosticar. Razón de presentación del caso. Caso Clínico: El caso corresponde a una mujer de 41 años con tiroides en base de la lengua diagnosticada incidentalmente con tomografía computarizada (TC), con antecedentes de hipotiroidismo y cáncer de mama derecha. Al examen físico de cuello no se palpa glándula tiroidea ni se observa masa o protuberancia en cavidad bucal. Por control del cáncer de mama, se solicita tomografía por emisión de positrones (PET) y ecografía de cuello, reportándose captación del radiofármaco en la región cervical anterior y superior de cuello, y ausencia de tejido glandular tiroideo a nivel habitual, respectivamente. Por cuanto, se realiza TC simple y contrastada observándose a nivel de la raíz de la lengua una imagen nodular hipercaptante que mide 23x20x20 mm, bien definida, contornos regulares, no infiltra tejidos adyacentes, impronta luz de la orofaringe, sin individualizar la glándula tiroides a nivel habitual, corroborando así el diagnóstico de tiroides ectópica lingual. Conclusión: El diagnóstico de tiroides ectópica en paciente adulto hipotiroideo es raro, por lo que debe considerarse la realización de TC si al examen físico y ecográfico no es palpable ni observable
Introduction: Cases of ectopic thyroid located at the base of the tongue are rare and difficult to diagnose congenital abnormalities. Reason for presenting the case. Clinical case: The case corresponds to a 41-year-old woman with thyroid based on the tongue diagnosed incidentally with computed tomography (CT), with a history of hypothyroidism and right breast cancer. On the physical examination of the neck, the thyroid gland is not palpated, and no mass or bump is observed in the oral cavity. For breast cancer control, positron emission tomography (PET) and neck ultrasound are requested, radiopharmaceutical uptake is reported in the anterior and upper cervical neck region, and absence of thyroid glandular tissue at the usual level, respectively. As a simple and contrasted CT scan, a hypercapting nodular image measuring 23x20x20 mm, well defined, regular contours is observed at the root of the tongue, does not infiltrate adjacent tissues, oropharynx light imprint, without individualizing the thyroid gland to usual level, thus corroborating the diagnosis of lingual ectopic thyroid. Conclusion: The diagnosis of ectopic thyroid in an adult hypothyroid patient is rare, so CT should be considered if the physical and ultrasound examination is not palpable or observable.
Assuntos
Humanos , Tomógrafos Computadorizados , Tireoide Lingual , Disgenesia da Tireoide , Doenças da Glândula Tireoide , Doença Crônica , EquadorRESUMO
Easy, economic, precise species authentication is currently necessary in many areas of research and diagnosis in molecular biology applied to conservation studies of endangered species. Here, we present a new method for the identification of three fox species of the Lycalopex genus in Chile. We developed an assay based on high-resolution melt analysis of the mitochondrial cytochrome B gene, allowing a simple, low cost, fast, and accurate species determination. To validate the assay applicability for noninvasive samples, we collected fecal samples in the Atacama Desert, finding unexpectedly one species outside of its known distribution range. We conclude that the assay has a potential to become a valuable tool for a standardized genetic monitoring of the Lycalopex species in Chile.
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To develop new drugs and vaccines for malaria elimination, it will be necessary to discover biological interventions, including small molecules that act against Plasmodium vivax exoerythrocytic forms. However, a robust in vitro culture system for P. vivax is still lacking. Thus, to study exoerythrocytic forms, researchers must have simultaneous access to fresh, temperature-controlled patient blood samples, as well as an anopheline mosquito colony. In addition, researchers must rely on native mosquito species to avoid introducing a potentially dangerous invasive species into a malaria-endemic region. Here, we report an in vitro culture system carried out on site in a malaria-endemic region for liver stage parasites of P. vivax sporozoites obtained from An. darlingi, the main malaria vector in the Americas. P. vivax sporozoites were obtained by dissection of salivary glands from infected An. darlingi mosquitoes and purified by Accudenz density gradient centrifugation. HC04 liver cells were exposed to P. vivax sporozoites and cultured up to 9 days. To overcome low P. vivax patient parasitemias, potentially lower mosquito vectorial capacity, and humid, nonsterile environmental conditions, a new antibiotic cocktail was included in tissue culture to prevent contamination. Culturing conditions supported exoerythrocytic (EEF) P. vivax liver stage growth up to 9 days and allowed for maturation into intrahepatocyte merosomes. Some of the identified small forms were resistant to atovaquone (1 µM) but sensitive to the phosphatidylinositol 4-kinase inhibitor, KDU691 (1 µM). This study reports a field-accessible EEF production process for drug discovery in a malaria-endemic site in which viable P. vivax sporozoites are used for drug studies using hepatocyte infection. Our data demonstrate that the development of meaningful, field-based resources for P. vivax liver stage drug screening and liver stage human malaria experimentation in the Amazon region is feasible.
Assuntos
Técnicas de Cultura de Células/métodos , Hepatócitos/parasitologia , Parasitologia/métodos , Plasmodium vivax/crescimento & desenvolvimento , Animais , Anopheles/parasitologia , Linhagem Celular , Humanos , Peru , Plasmodium vivax/isolamento & purificação , Glândulas Salivares/parasitologiaRESUMO
In vitro culture of Plasmodium vivax liver stages underlies key understandings of the fundamental biology of this parasite, particularly the latent, hyponozoite stage, toward drug and vaccine development. Here, we report systematic production of Plasmodium vivax sporozoites in colonized Anopheles darlingi mosquitoes in the Peruvian Amazon. Human subject-derived P. vivax-infected blood was fed to Anopheles darlingi females using standard membrane feedings assays. Optimizing A. darlingi infection and sporozoite production included replacement of infected patient donor serum with naïve donor serum, comparing anticoagulants in processing blood samples, and addition of penicillin-streptomycin and ATP to infectious blood meals. Replacement of donor serum by naïve serum in the P. vivax donor blood increased oocysts in the mosquito midgut, and heparin, as anticoagulant, was associated with the highest sporozoite yields. Maintaining blood-fed mosquitoes on penicillin-streptomycin in sugar significantly extended mosquito survival which enabled greater sporozoite yield. In this study, we have shown that a robust P. vivax sporozoite production is feasible in a malaria-endemic setting where infected subjects and a stable A. darlingi colony are brought together, with optimized laboratory conditions.
Assuntos
Anopheles/parasitologia , Parasitologia/métodos , Plasmodium vivax/crescimento & desenvolvimento , Esporozoítos/crescimento & desenvolvimento , Animais , Feminino , Trato Gastrointestinal/parasitologia , Peru , Plasmodium vivax/isolamento & purificação , Esporozoítos/isolamento & purificaçãoRESUMO
ResumenLas prácticas del cuidado del embarazo y el parto varían ampliamente entre los países, las instituciones y los diferentes equipos encargados del cuidado obstétrico: en este contexto con prácticas tan diversas, la práctica clínica basada en la evidencia permite que el accionar de los profesionales encargados del cuidado obstétrico se fundamente en la mejor evidencia disponible. El objetivo del presente estudio es analizar la mejor evidencia científica disponible sobre los efectos adversos del uso del balón cervical durante y posterior a la labor de parto, en comparación con el uso de prostaglandinas endocervicales para la inducción del parto en mujeres con embarazo a término. La secuencia de etapas para la recolección de la información se inició con la aplicación del mapa de búsqueda en las bases de datos MEDLINE, PUBMED y COCHRANE LIBRARY, a partir de los siguientes criterios de filtro de información: artículos publicados entre los años 2010 al 2015, mujeres gestantes de cualquier edad, únicamente se incluyó estudios como ensayos aleatorizados controlados, revisiones sistemáticas, meta-análisis o guías de práctica clínica y de preferencia artículos científicos en idioma inglés o portugués. Esta búsqueda y análisis de la evidencia encontrada se realizó durante los meses de abril y mayo del año 2015 por dos revisores. Los resultados obtenidos para el análisis crítico fueron revisados minuciosamente a través de la plataforma informática FCL 2.0 con las plantillas de ensayo clínico y revisión sistemática incluidas en los anexos. Se concluye que la utilización del balón endocervical comparado con el uso de prostaglandinas endocervicales presenta menos efectos adversos de manera específica durante la labor del parto. En relación con los efectos adversos posteriores, no se encuentra mayor diferencia entre uno u otro método.
AbstractPregnancy and childbirth care practices vary widely across countries, institutions, and different obstetrical care teams: in this context with such diverse practices, evidence-based clinical practice allows the Obstetric care is based on the best available evidence. The objective of the present study is to analyze the best available scientific evidence on the adverse effects of cervical balloon use during and after labor, compared to the use of endocervical prostaglandins for induction of labor in women with term pregnancy. The sequence of steps for the collection of information was initiated with the application of the search map in the databases MEDLINE, PUBMED and COCHRANE LIBRARY, based on the following information filter criteria: articles published between the years 2010 to 2015, Pregnant women of any age, only included studies such as randomized controlled trials, systematic reviews, meta-analyzes or guidelines of clinical practice and preferably scientific papers in English or Portuguese. This search and analysis of the evidence found was carried out during the months of April and May of the year 2015 by two reviewers. The results obtained for the critical analysis were carefully reviewed through the FCL 2.0 computer platform with the clinical trial templates and systematic review included in the annexes. It is concluded that the use of the endocervical balloon compared to the use of endocervical prostaglandins presents less adverse effects specifically during labor. In relation to the subsequent adverse effects, no greater difference is found between one or the other method.
ResumoPráticas de cuidados a gravidez eo parto variam amplamente entre os países, instituições e diferentes equipas de cuidados obstétricos; neste contexto como práticas diversas, a prática clínica baseada em evidências permite que as ações dos profissionais responsáveis pela assistência obstétrica é baseada na melhor evidência disponível. O objetivo deste estudo é analisar a melhor evidência científica disponível sobre os efeitos adversos durante e após o parto com o uso de bola cervical em comparação com o uso de prostaglandina endocervical para indução do parto em mulheres com gravidez a termo. A sequência dos passos para a recolha de dados começa com a busca do mapa aplicação em Medline, PubMed e os dados Cochrane Library, onde os seguintes critérios de filtro de informação artigos introduzidos foram seleccionados publicação período entre 2010 e 2015, a população foi delimitada a mulheres grávidas de qualquer idade, digite apenas ensaios estudos clínicos randomizados, revisões sistemáticas, meta-análises ou diretrizes de prática clínica e artigos científicos de preferência em Inglês ou Português foram incluídos. Esta pesquisa e análise da evidência encontrada foi realizado durante os meses de Abril e Maio de 2015, dois colaboradores. Os resultados obtidos para a análise crítica foram cuidadosamente controlados através da plataforma FCL computador 2,0 modelos ensaio clínico e revisão sistemática estão incluídos nos anexos. Concluiu-se que o uso de bola endocervical em comparação com a utilização de prostaglandinas endocervicais tem menos efeitos adversos especificamente durante o trabalho de parto. Em ligação com os efeitos adversos subsequentes não é maior diferença entre qualquer um dos métodos.
Assuntos
Extração Obstétrica/instrumentação , Complicações do Trabalho de Parto , Trabalho de Parto Induzido , Enfermeiros ObstétricosRESUMO
Previous microsatellite analyses of sympatric populations of Plasmodium vivax and Plasmodium falciparum in Brazil revealed higher diversity in the former species. However, it remains unclear whether regional species-specific differences in prevalence and transmission levels might account for these findings. Here, we examine sympatric populations of P. vivax (n=87) and P. falciparum (n=164) parasites from Pursat province, Western Cambodia, where both species are similarly prevalent. Using 10 genome-wide microsatellites for P. falciparum and 13 for P. vivax, we found that the P. vivax population was more diverse than the sympatric P. falciparum population (average virtual heterozygosity [HE], 0.87 vs. 0.66, P=0.003), with more multiple-clone infections (89.6% vs. 47.6%) and larger mean number of alleles per marker (16.2 vs. 11.1, P=0.07). Both populations showed significant multi-locus linkage disequilibrium suggestive of a predominantly clonal mode of parasite reproduction. The higher microsatellite diversity found in P. vivax isolates, compared to sympatric P. falciparum isolates, does not necessarily result from local differences in transmission level and may reflect differences in population history between species or increased mutation rates in P. vivax.
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Variação Genética , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Repetições de Microssatélites/genética , Plasmodium falciparum/genética , Plasmodium vivax/genética , Animais , Anopheles/parasitologia , Camboja/epidemiologia , Feminino , Frequência do Gene , Marcadores Genéticos , Haplótipos , Humanos , Insetos Vetores/parasitologia , Desequilíbrio de Ligação , Malária Falciparum/epidemiologia , Malária Falciparum/transmissão , Malária Vivax/epidemiologia , Malária Vivax/transmissão , Masculino , Prevalência , Especificidade da Espécie , Simpatria/genéticaRESUMO
Microsatellites have been increasingly used to investigate the population structure of malaria parasites, to map genetic loci contributing to phenotypes such as drug resistance and virulence in laboratory crosses and genome-wide association studies and to distinguish between treatment failures and new infections in clinical trials. Here, we provide optimized protocols for genotyping highly polymorphic microsatellites sampled from across the genomes of the human malaria parasites Plasmodium falciparum and P. vivax that have been extensively used in research laboratories worldwide.
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DNA de Protozoário/análise , Repetições de Microssatélites/genética , Plasmodium falciparum/genética , Plasmodium vivax/genética , Reação em Cadeia da Polimerase/métodos , Animais , Primers do DNA , DNA de Protozoário/genética , Genoma de Protozoário , Genótipo , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Plasmodium falciparum/classificação , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/classificação , Plasmodium vivax/isolamento & purificaçãoRESUMO
Emerging resistance to chloroquine (CQ) poses a major challenge for Plasmodium vivax malaria control, and nucleotide substitutions and copy number variation in the P. vivax multidrug resistance 1 (pvmdr-1) locus, which encodes a digestive vacuole membrane transporter, may modulate this phenotype. We describe patterns of genetic variation in pvmdr-1 alleles from Acre and Amazonas in northwestern Brazil, and compare then with those reported in other malaria-endemic regions. The pvmdr-1 mutation Y976F, which is associated with CQ resistance in Southeast Asia and Oceania, remains rare in northwestern Brazil (1.8%) and its prevalence mirrors that of CQ resistance worldwide. Gene amplification of pvmdr-1, which is associated with mefloquine resistance but increased susceptibility to CQ, remains relatively rare in northwestern Brazil (0.9%) and globally (< 4%), but became common (> 10%) in Tak Province, Thailand, possibly because of drug-mediated selection. The global database we have assembled provides a baseline for further studies of genetic variation in pvmdr-1 and drug resistance in P. vivax malaria.
Assuntos
Variações do Número de Cópias de DNA , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium vivax/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único , Proteínas de Protozoários/genética , Animais , Sequência de Bases , Primers do DNA , Variação Genética , Plasmodium vivax/genética , Reação em Cadeia da PolimeraseRESUMO
BACKGROUND: The ideal malaria parasite populations for initial mapping of genomic regions contributing to phenotypes such as drug resistance and virulence, through genome-wide association studies, are those with high genetic diversity, allowing for numerous informative markers, and rare meiotic recombination, allowing for strong linkage disequilibrium (LD) between markers and phenotype-determining loci. However, levels of genetic diversity and LD in field populations of the major human malaria parasite P. vivax remain little characterized. RESULTS: We examined single-nucleotide polymorphisms (SNPs) and LD patterns across a 100-kb chromosome segment of P. vivax in 238 field isolates from areas of low to moderate malaria endemicity in South America and Asia, where LD tends to be more extensive than in holoendemic populations, and in two monkey-adapted strains (Salvador-I, from El Salvador, and Belem, from Brazil). We found varying levels of SNP diversity and LD across populations, with the highest diversity and strongest LD in the area of lowest malaria transmission. We found several clusters of contiguous markers with rare meiotic recombination and characterized a relatively conserved haplotype structure among populations, suggesting the existence of recombination hotspots in the genome region analyzed. Both silent and nonsynonymous SNPs revealed substantial between-population differentiation, which accounted for ~40% of the overall genetic diversity observed. Although parasites clustered according to their continental origin, we found evidence for substructure within the Brazilian population of P. vivax. We also explored between-population differentiation patterns revealed by loci putatively affected by natural selection and found marked geographic variation in frequencies of nucleotide substitutions at the pvmdr-1 locus, putatively associated with drug resistance. CONCLUSION: These findings support the feasibility of genome-wide association studies in carefully selected populations of P. vivax, using relatively low densities of markers, but underscore the risk of false positives caused by population structure at both local and regional levels.
Assuntos
Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação , Plasmodium vivax/genética , Polimorfismo de Nucleotídeo Único , Animais , Genética Populacional , Seleção GenéticaRESUMO
The circumsporozoite protein (CSP) of Plasmodium vivax, a major target for malaria vaccine development, has immunodominant B-cell epitopes mapped to central nonapeptide repeat arrays. To determine whether rearrangements of repeat motifs during mitotic DNA replication of parasites create significant CSP diversity under conditions of low effective meiotic recombination rates, we examined csp alleles from sympatric P. vivax isolates systematically sampled from an area of low malaria endemicity in Brazil over a period of 14 months. Nine unique csp types, comprising six different nonapeptide repeats, were observed in 45 isolates analyzed. Identical or nearly identical repeats predominated in most arrays, consistent with their recent expansion. We found strong linkage disequilibrium at sites across the chromosome 8 segment flanking the csp locus, consistent with rare meiotic recombination in this region. We conclude that CSP repeat diversity may not be severely constrained by rare meiotic recombination in areas of low malaria endemicity. New repeat variants may be readily created by nonhomologous recombination even when meiotic recombination is rare, with potential implications for CSP-based vaccine development.
Assuntos
Evolução Molecular , Epitopos Imunodominantes/genética , Malária Vivax/parasitologia , Plasmodium vivax/genética , Proteínas de Protozoários/genética , Sequências de Repetição em Tandem , Sequência de Bases , Estudos de Coortes , Haplótipos , Humanos , Desequilíbrio de Ligação , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência , Fatores de TempoRESUMO
Clinical trials documented alarming post-treatment Plasmodium vivax recurrence rates caused by recrudescence of surviving asexual blood stages, relapse from hypnozoites, or new infections. Here we describe high rates of P. vivax recurrence (26-40% 180 days after treatment) in two cohorts of rural Amazonians exposed to low levels of malaria transmission after a vivax malaria episode treated with chloroquine-primaquine. Microsatellite analysis of 28 paired acute infection and recurrence parasites showed only two pairs of identical haplotypes (consistent with recrudescences or reactivation of homologous hypnozoites) and four pairs of related haplotypes (sharing alleles at 11-13 of 14 microsatellites analyzed). Local isolates of P. vivax were extraordinarily diverse and rarely shared the same haplotype, indicating that frequent recurrences did not favor the persistence or reappearance of clonal lineages of parasites in the population. This fast haplotype replacement rate may represent the typical population dynamics of neutral polymorphisms in parasites from low-endemicity areas.
Assuntos
Malária Vivax/parasitologia , Parasitemia/parasitologia , Plasmodium vivax/genética , Animais , Antimaláricos/uso terapêutico , Brasil/epidemiologia , Cloroquina/uso terapêutico , Resistência a Medicamentos , Haplótipos , Humanos , Malária Vivax/tratamento farmacológico , Malária Vivax/epidemiologia , Repetições de Microssatélites/genética , Primaquina/uso terapêutico , Recidiva , População Rural , Fatores de TempoRESUMO
Plasmodium vivax parasites with chloroquine resistance (CQR) are already circulating in the Brazilian Amazon. Complete single-nucleotide polymorphism (SNP) analyses of coding and noncoding sequences of the pvmdr1 and pvcrt-o genes revealed no associations with CQR, even if some mutations had not been randomly selected. In addition, striking differences in the topologies and numbers of SNPs in these transporter genes between P. vivax and P. falciparum reinforce the idea that mechanisms other than mutations may explain this virulent phenotype in P. vivax.
Assuntos
Cloroquina/farmacologia , Resistência a Medicamentos/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium vivax/efeitos dos fármacos , Plasmodium vivax/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Protozoários/genética , Animais , Antimaláricos/farmacologia , Brasil , Modelos Biológicos , Dados de Sequência MolecularRESUMO
We used mixtures of genomic DNA from two genetically distinct isolates from Brazil, 42M and 312M, to investigate how accurately 12-locus microsatellite typing describes the overall genetic diversity and characterizes multilocus haplotypes in multiple-clone Plasmodium vivax infections. We found varying PCR amplification efficiencies of microsatellite alleles; for example, from the same 1:1 mixture of 42M and 312M DNA we amplified predominantly 312M-type alleles at 10 loci and 42M-type alleles at 2 loci. All microsatellite alleles were accurately scored in 1:0.5 and 1:0.25 312M:42M DNA mixtures, even when minor peak heights did not meet previously suggested criteria for minor allele detection in multiple-clone infections. Relative proportions of major and minor alleles were unaffected by multiple displacement amplification of template DNA prior to PCR-based microsatellite typing. Although microsatellite typing may detect minor alleles in clone mixtures, amplification biases may lead to inaccurate assignment of predominant haplotypes in multiple-clone P. vivax infections.
Assuntos
DNA de Protozoário/análise , Malária Vivax/parasitologia , Repetições de Microssatélites/genética , Plasmodium vivax/classificação , Plasmodium vivax/genética , Alelos , Animais , Amplificação de Genes , Genoma de Protozoário/genética , Haplótipos/genética , Humanos , Reação em Cadeia da PolimeraseRESUMO
La resistencia insulínica o insulinorresistencia (IR) es una disminución en la función biológica de esta hormona caracterizada por un alto nivel de la insulina plasmática que es requerido para mantener la homeostasis metabólica.Se ha estimado que aproximadamente un 25% de individuos tienen IR. Su estudio ha cobrado gran importancia en los últimos años en el ámbito médico, pues se ha demostrado que la IR conduce al desarrollo de un síndrome de insulinorresistencia (SIR), que comprende un conjunto de alteraciones metabólicas (hiperinsulinismo, obesidad visceral, hipertensión arterial sistólica y diastólica y dislipidemia). Todas estas alteraciones son factores de riesgo conocidos de enfermedad cardiovascular, siendo ésta una de las principales causas de morbilidad y mortalidad a nivel mundial. Fue Reaven quien en 1988 sugirió que la diabetes mellitus, la hipertensión arterial y la dislipemia eran factores que tendían a ocurrir en un mismo individuo en la forma de un síndrome, al que denominó X, en el que la IR constituía el mecanismo fisiopatológico básico.El incremento en la incidencia de enfermedades como la diabetes tipo 2, enfermedad cardiovascular y obesidad, es producido en muchos casos, por el aumento en la prevalencia de IR en la población, lo que podría atribuirse, en parte, a los cambios en el estilo de vida que ha experimentado la sociedad occidental a lo largo de las últimas décadas.
Insulin resistance (IR) is a decrease of the biological function of this hormone characterized by a high level of plasmic insulin which is required for the metabolic homeostasis.It is estimated that approximately 25% of people have IR. Its study has acquired great importance in the last years, because it has been demonstrated to lead to an insulin resistance syndrome (IRS), which includes various metabolic disorders: hiperinsulinesm, visceral obesity, systolic and diastolic hypertension, dislipidemia. All these alterations are well known to be risk factors for coronary heart disease, constituting one of the main causes of morbimortality worldwide.It was reaven who suggested in 1988, that diabetes mellitus, arterial hypertension and dislipidemia are factors which tended to occur in this the same individual as a syndrome, which he demonstrated X, where the IR constituted the basic fisiopathological mechanism.The increase in the incidence of diseases such as DM2, cardiovascular disease, and obesity is due mainly, to the increase in the prevalence of IR among the population, which could be attributed to the life style changes experimented by the occidental society during the last decades.
Assuntos
Masculino , Adulto , Feminino , Resistência à Insulina , Receptor de Insulina , Índice de Massa Corporal , Antagonistas da Insulina , ObesidadeRESUMO
Considerando que no ha sido posible demostrar la efectividad de la profilaxis antibiótica en la prevención de Endocarditis Infecciosa (EI) en seres humanos y que se ha observado un significativo aumento de esta enfermedad en pacientes sin cardiopatía previa, la relación costo/beneficio se inclina progresivamente a la no-recomendación de su uso universal. La posibilidad de desarrollar EI se relaciona con: 1) ciertos procedimientos médicos que se asocian a una alta tasa de bacteremias transitorias; 2) agresividad del germen; 3)cardiopatía previa (hay enfermedades más susceptibles de ser colonizadas por gérmenes); y 4) factores relacionados con el huésped (condiciones predisponentes o favorecedoras de la expresión de esta enfermedad en corazones previamente sanos; hemodiálisis, inmunodepresión, uso de marcapasos definitivos, drogadicción endovenosa, enfermedades inflamatorias crónicas, SIDA y utilización de mayores técnicas endovenosas invasivas en las unidades de cuidados intensivos). Probablemente su utilización futura se limitará a procedimientos con alto porcentaje de invasión y en poblaciones muy específicas (portador de prótesis valvulares, antecedentes de EI previa y congénitos con secuelas hemodinámicas); sin embargo, mientras se acumulan mayores evidencias, es aconsejable mantener las actuales recomendaciones de la AHA sobre prevención de la enfermedad con el ánimo de unificar criterios de manejo, quedando todas estas indicaciones supeditadas a modificaciones aconsejadas por la realidad de cada medio hospitalario.