Niveles de referencia para diagnóstico según PUBMED: ¿es suficiente la información disponible? / Diagnostic reference levels according to PUBMED: is the information available sufficient?

RESUMEN Los Niveles de Referencia para Diagnóstico (NRD) son una herramienta dinámica que gana cada vez una mayor importancia para la optimización de las exposiciones médicas. La disponibilidad de información científica es esencial en este proceso de optimización para Medicina Nuclear (MN) y Radiología Diagnóstica (RD). Este trabajo presenta un estudio de la disponibilidad de información sobre los NRD para MN y RD en la base PubMed, en los últimos 20 años, empleando diferentes palabras clave. Se analizó de forma crítica la información disponible, buscando los cambios principales que se han producido como tendencia en diferentes aspectos del establecimiento de los NRD. Se verificó un desbalance significativo en la disponibilidad de literatura científica en estas dos áreas, aunque se ha incrementado la información para equipos híbridos y de forma general para todas las tecnologías. Este desbalance se hace mayor para estudios de medicina nuclear en pediatría. Se observaron avances en la forma de recolectar datos, la manera de organizar la información y analizarla, en especial con la disponibilidad de sistemas de monitoreo de dosis. Se encontró que, en los estudios TC e intervencionismo, las agrupaciones por localización anatómica están siendo acotadas o restringidas, por indicaciones clínicas que tienen similitudes en los requisitos de calidad de imagen para el diagnóstico adecuado. Similarmente en MN se vislumbra la incorporación de la actividad por peso como NRD en las tecnologías híbridas y estudios pediátricos. Este estudio demuestra que, en general, la literatura científica disponible sobre los NRD es mucho más amplia para pacientes adultos. Se requiere más estudios pediátricos, especialmente en el área de MN

ABSTRACT Diagnostic Reference Levels (DRLs) are a dynamic tool that is gaining more and more importance for the optimization of medical exposures. The availability of scientific information is essential in this optimization process for Nuclear Medicine (NM) and Diagnostic Radiology (DR). This work presents a revision of the information's availability about DRL in the PubMed database, in the last 20 years, using different search combinations. The available information was critically analyzed, looking for the main changes that have occurred as a trend in different aspects of the establishment of the NRD. A significant disparity in the amount of information between the two areas on the subject was verified, although there has been an increase of available scientific papers for hybrid equipment, and in general for all technologies. The disparity becomes greater for NM studies in pediatrics population. The way to collect data, the mode to organize the information and analyze it, has also undergone changes, mainly with radiation dose management systems. In CT and interventional studies, the grouping by anatomical locations is being constrained or modulated by clinical indications with analogous image quality requirements for proper diagnosis. Something similar happens in MN, where the incorporation of activity/patient's weight is envisioned as NRD for hybrid technologies and pediatric studies. In general, the study showed that, the scientific paper's availability about DRL for adult population are much wider. More pediatric studies on these subjects are needed, especially in NM

Classification of different degrees of adiposity in sedentary rats

In experimental studies, several parameters, such as body weight, body mass index, adiposity index, and dual-energy X-ray absorptiometry, have commonly been used to demonstrate increased adiposity and investigate the mechanisms underlying obesity and sedentary lifestyles. However, these investigations have not classified the degree of adiposity nor defined adiposity categories for rats, such as normal, overweight, and obese. The aim of the study was to characterize the degree of adiposity in rats fed a high-fat diet using cluster analysis and to create adiposity intervals in an experimental model of obesity. Thirty-day-old male Wistar rats were fed a normal (n=41) or a high-fat (n=43) diet for 15 weeks. Obesity was defined based on the adiposity index; and the degree of adiposity was evaluated using cluster analysis. Cluster analysis allowed the rats to be classified into two groups (overweight and obese). The obese group displayed significantly higher total body fat and a higher adiposity index compared with those of the overweight group. No differences in systolic blood pressure or nonesterified fatty acid, glucose, total cholesterol, or triglyceride levels were observed between the obese and overweight groups. The adiposity index of the obese group was positively correlated with final body weight, total body fat, and leptin levels. Despite the classification of sedentary rats into overweight and obese groups, it was not possible to identify differences in the comorbidities between the two groups.

Multiple facets of HIV-associated renal disease

HIV infection has a broad spectrum of renal manifestations. This study examined the clinical and histological manifestations of HIV-associated renal disease, and predictors of renal outcomes. Sixty-one (64% male, mean age 45 years) HIV patients were retrospectively evaluated. Clinical presentation and renal histopathology were assessed, as well as CD4 T-cell count and viral load. The predictive value of histological lesion, baseline CD4 cell count and viral load for end-stage renal disease (ESRD) or death were determined using the Cox regression model. The outcomes of chronic kidney disease (CKD) and ESRD or death were evaluated by baseline CD4 cell count. The percent distribution at initial clinical presentation was non-nephrotic proteinuria (54%), acute kidney injury (28%), nephrotic syndrome (23%), and chronic kidney disease (22%). Focal segmental glomerulosclerosis (28%), mainly the collapsing form (HIVAN), acute interstitial nephritis (AIN) (26%), and immune complex-mediated glomerulonephritis (ICGN) (25%) were the predominant renal histology. Baseline CD4 cell count ≥200 cells/mm3 was a protective factor against CKD (hazard ratio=0.997; 95%CI=0.994-0.999; P=0.012). At last follow-up, 64% of patients with baseline CD4 ≥200 cells/mm3 had eGFR >60 mL·min-1·(1.73 m2)-1 compared to the other 35% of patients who presented with CD4 <200 cells/mm3 (log rank=9.043, P=0.003). In conclusion, the main histological lesion of HIV-associated renal disease was HIVAN, followed by AIN and ICGN. These findings reinforce the need to biopsy HIV patients with kidney impairment and/or proteinuria. Baseline CD4 cell count ≥200 cells/mm3 was associated with better renal function after 2 years of follow-up.

Abordagem prática dos distúrbios de ritmo em pediatria / A practical approach to rhythm disorders in pediatrics

As arritmias podem ser causadas por alterações na geração do estímulo elétrico cardíaco, na propagação deste estímulo através do coração ou pela combinação de ambas. Normalmente, não se espera que o pediatra geral seja capaz de identificar e tratar todas as arritmias cardíacas, ficando essa tarefa para o cardiologista. Entretanto, é função do pediatra saber identificar e tratar as arritmias que se manifestam como urgênciaou emergência, ou seja, as que levam à instabilidade hemodinâmica ou choque, pois, nesses casos, a vida do paciente depende da rapidez com que as medidas terapêuticas são tomadas. Visa-se, neste artigo, demonstrar pontos básicos para facilitar a avaliação e abordagem primária das principais arritmias cardíacas pediátricas e orientar os primeiros e principais passos do tratamento.

Arrhythmias may be caused by changes in the generation of cardiac electrical stimulus, in stimulus conduction through the heart, or by a combination of both. The general pediatrician it is not usually expected to be able to identify and treat all cardiac arrhythmias, referring to the cardiologist for this task. However, pediatrician are expected to be able to identify and treat arrhythmias manifested in urgent or emergency care, i.e. those that lead to hemodynamic instability or to shock, given that, in such cases, the patient's life depends on how fast the therapeutic measures are taken. In this article we aim to demonstrate some basic pointers that facilitate the assessment and primary approach to the main pediatric cardiac arrhythmias and to guide in the first and main steps of treatment.

La producción de lo normal y lo anormal: un estudio sobre creencias de género y sexualidad entre docentes de escuelas municipales de Novo Hamburgo/Brasil / The production of normal and abnormal: a study on gender and sexuality beliefs among teachers of public schools in Novo Hamburgo/Brazil

Este artículo integra los resultados de un estudio que tuvo como objetivo examinar creencias sobre género y sexualidad, que fundamentan las prácticas de educación sexual en instituciones escolares de nivel fundamental en Novo Hamburgo (Rio Grande do Sul, Brasil). En primer lugar, rescatamos algunas aportaciones para la comprensión de la educación sexual, específicamente a partir de presupuestos teóricos provenientes de estudios culturales y de género, así como de estudios actuales que abordan el tema. También se presentan resultados cualitativos obtenidos a través de entrevistas realizadas a docentes de las cincuenta y seis escuelas del municipio.

Evaluación de la maloculusión clase III según su morfología: pacientes de ortodoncia interceptiva / Evaluation of Class III malocclusion by morphology: interceptive orthodontic patients

El propósito de este estudio es investigar las características morfológicas de la estructura craneofacial en un grupo de niños venezolanos con maloclusión Clase III. Los registros radiográficos pre-tratamiento de 55 niños con maloclusión Clase I y 79 con maloclusión Clase III, con rango de edades de 3-11, años fueron seleccionados para análisis cefalométrico. Los niños con maloclusión Clase III demostraron diferencias significativas en su morfología craneofacial cuando fueron comparados con el grupo control, manifestándose con una base craneana anterior más corta, el maxilar pequeño y retrusivo; la mandíbula fue de mayor longitud y se encuentra más adelante, manifestaron tendencia a exhibir el tercio facial inferior normal en este grupo de estudio. Los incisivos tanto maxilares como mandibulares no mostraron diferencias significativas sin embargo los incisivos maxilares se presentaron protruidos y los mandibulares ligeramente retroinclindados. El análisis de los distintos componentes de la maloclusión Clase III, confirmó que la mayoría de estos pacientes mostraban un maxilar pequeño y retraído, en un 97%, la mandíbula fue protrusiva en 75% y las alturas faciales antero inferiores estuvieron normales en más de la mitad de los sujetos de este grupo (67%). La combinación más frecuente quedó representada por el 46% de la muestra del grupo de estudio, conformada por un maxilar retruido, la mandíbula prognática y la altura antero inferior de la cara normal. El patrón esquelético es variable en la Clase III

The purpose of this study is to investigate the morphologic characteristics of the craniofacial complex of a group of Venezuelan children with Class III malocclusion. Pre-treatment radiographic records of 55 children with Class I malocclusion and 79 with Class III malocclusion (ages 3 to 11 years) were selected for cephalometric analysis. Class III children showed distinct differences in their craniofacial morphology when compared with control group, exhibiting a significantly shorter anterior cranial base, maxillary length was significantly smaller and retrusive, and the jaw was more posteriorly positioned; the mandibular length was significantly longer, accompanied by a more forward positioning. In this study group, patients with Class III malocclusion tended to exhibit a normal lower facial third. Neither maxillary nor mandibular incisors showed significant differences, however the former were protruded and the latter slightly retruded. Analysis of the different components of Class III malocclusion confirmed that 97% of these patients exhibited a small and retrusive maxilla; 75% showed protrusive maxilla, and in 67% of the patients anteroinferior facial heights were normal. The most frequent combination were represented by 46% of the group study patients exhibiting a retrusive maxilla, prognatic jaw, and a normal anterioinferior facial height. Class III skeletal pattern is variable

Principais causas de condenação de frangos em abatedouro de aves e coelhos no Triangulo Mineiro / Major causes of condemnation of broilers at slaughter of poultry and rabbits in the Triangulo Mineiro

Diversas causas promovem a condenação de frangos em abatedouro avícola. É responsabilidade do Serviço de Inspeção fiscalizar os abatedouros e destinar os seus produtos ao consumo direto, aproveitamento condicional ou a sua condenação quando impróprios ao consumo humano por problemas de ordem sanitária ou higiênica. O objetivo do trabalho foi conhecer e quantificar as principais causas de condenações de frangos, no período de 1999 a 2003, em um Frigorífico de Aves e Coelhos localizado na região do Triângulo Mineiro. A análise dos dados fornecidos pelo SIF apontou como resultado em ordem de ocorrência as principais causas de condenações que foram: contaminação; dermatose; contusão; ave morta; sangria inadequada; escaldagem excessiva; aspecto repugnante; artrite; aerossaculite e caquexia. Esse conhecimento viabiliza a implantação de medidas higiênicas e sanitárias preventivas, com vistas à qualidade do produto e a diminuição dos custos a partir de menores índices de condenações.

Edge effects and landscape matrix use by a small mammal community in fragments of semideciduous submontane forest in Mato Grosso, Brazil / Efeitos de borda e uso da matriz por uma comunidade de pequenos mamíferos em fragmentos de floresta semidecidual submontana no Mato Grosso, Brasil

A community of small mammals was studied in seasonal semideciduous submontane forest in the state of Mato Grosso, Brazil. This study evaluated the use of edge and matrix pasture, by different small mammal species. Overall, 31 areas were studied, with a total sampling effort of 33,800 trap x nights. Only seven of the 25 species captured in the study sites were able to use the pasture matrix; we classified these species as generalists. Fourteen species were found to be intermediate in habits, being able to use forest edges. We found only four species habitat specialists, occurring only on transect lines in the interior of the fragment, at least 150 m from the edge. Transects located in the pasture matrix and 50 m from the edge had significantly lower species richness and abundance than transects located in the fragment edge or in the interior of the fragment. All transects located within the fragment had similar species richness and abundance, but transects located 50 m from the edge had slightly lower, but non-significant, species richness than transects located 100 m apart from edges. Rarefaction curves demonstrated that only medium-sized fragments (100 300 ha) reached an asymptote of species accumulation. The other areas require further sampling, or more sampling transect, before species accumulation curves stabilize, due to a continued increase in species number.

Uma comunidade de pequenos mamíferos foi estudada em fragmentos de floresta estacional semidecidual submontana no Estado de Mato Grosso, Brasil. Nesse estudo, buscou-se avaliar o uso da borda e da matriz de pastagem pelas diferentes espécies. No total, 31 áreas foram estudadas, com um esforço total de 33.800 armadilhas x noite. Apenas sete das 25 espécies capturadas foram capazes de utilizar a matriz de pastagem, sendo estas consideradas generalistas. Quatorze foram consideradas intermediárias no uso do habitat, sendo capazes de utilizar habitats de borda. Encontramos apenas quatro especialistas, ocorrendo somente nas transecções do interior do fragmento, a aproximadamente 150 m da borda. Dentre todas as transecções utilizadas para amostragem, a disposta na matriz de pastagem, a 50 m da borda, demonstrou ser significativamente menos rica e abundante que as dispostas na borda e no interior dos fragmentos. Todas as transecções localizadas dentro do fragmento tiveram riqueza e abundância de espécies similares, porém a transecção localizada a 50 m da borda teve uma tendência a ser menos rica que a transecção a 100 m. Através de ajustes das curvas de rarefação, somente uma das áreas considerada de médio porte, entre 100 a 300 ha., atingiu uma assíntota. As outras áreas necessitam de um maior número de transecções, a fim de se obter uma estabilização das curvas, pois continuaram a acrescentar espécies.

Prevalence and risk factors for human toxoplasmosis in a rural community

Toxoplasma gondii infection may lead to important pathological questions, especially in rural areas, where several sources of infection exist. Therefore, it is important to determine risk factors in order to establish adequate prophylactic measures. The present study aimed to assess the prevalence and risk factors involved in human toxoplasmosis infection in a rural community, in Eldorado, Mato Grosso do Sul State, Brazil. This community was composed of 185 farms - with 671 inhabitants - from which 20 were randomly chosen. In these farms, blood samples were collected from rural workers, who also answered a risk factor questionnaire. Serum samples were analyzed by means of direct agglutination test for the detection of anti-Toxoplasma gondii antibodies. From 73 samples collected, 79.45% were positive. None of the studied variables was significantly associated with the prevalence of the infection. However, among the individuals who reported eyesight impairments, 94.4% had anti-T. gondii antibodies, compared with 74.0% who did not report eyesight changes (p = 0.0594). Moreover, most individuals in the study (68.20%) were older than 18 years and presented 84.44% positivity, compared with 66.67% of positive individuals younger than 18 years old. We were able to conclude that a high prevalence of antibodies did not imply significant associations with the risk factors studied.(AU)

Schistosome/mollusk: genetic compatibility

Schistosomiasis remains one of the most prevalent parasitic infections and has significant economic and public health consequences in many developing countries. Economic development and improvement in standard of living in these countries are dependent on the elimination of this odious disease. For the control of Schistosomiasis, understanding the host/parasite association is important, since the host parasite relationship is often complex and since questions remain concerning the susceptibility of snails to infection by respective trematodes and their specificity and suitability as hosts for continued parasite development. Thus, the long term aim of this research is to learn more about the genetic basis of the snail/parasite relationship with the hope of finding novel ways to disrupt the transmission of this disease. In the current research, genetic variability among susceptible and resistant strains within and between Biomphalaria glabrata and B. tenagophila was investigated using RAPD-PCR. The results indicate great genetic variations within the two snail species using three different primers (intrapopulational variations), while specimens from the same snail species showed few individual differences between the susceptible and resistant strains (interpopulational variation).