Alterações eritrocitárias induzidas pelo exercício físico

Evidências crescentes têm demonstrado que o exercício prejudica a estrutura da membrana eritrocitária, como consequência do aumento do estresse físico e químico. O óxido nítrico (NO) derivado dos eritrócitos afeta a fluidez da membrana e a sua biodisponibilidade depende do equilíbrio entre a sua síntese e eliminação por espécies reativas de oxigênio. Nós investigamos se o exercício realizado em diferentes intensidades afetaria biodisponibilidade do NO eritrocitário e se levaria a um quadro de estresse oxidativo. Dez homens (26 4 anos, VO2pico 44,1 4,3 mL.kg-1.min-1) realizaram um teste cardiopulmonar máximo em esteira e um teste de exercício submáximo a 70% VO2pico durante 30 min. O sangue foi coletado em repouso e imediatamente após os exercícios para isolamento dos eritrócitos. O exercício máximo aumentou a contagem de eritrócitos, hemoglobina e hematócrito, sem levar a qualquer alteração na massa corporal que pudesse sugerir hemoconcentração devido a uma redução do volume plasmático. Observou-se uma diminuição do influxo de L-arginina depois do teste submáximo, mas não no teste máximo. No entanto, a atividade da óxido nítrico sintase, ou seja, a produção de NO, foi aumentada após o teste máximo. Os níveis de GMPc não se alteraram após ambos os teste de exercício. Em relação aos biomarcadores de estresse oxidativo, o exercício submáximo reduziu a oxidação proteica e aumentou a atividade da catalase e a expressão da glutationa peroxidase, enquanto que o exercício máximo levou a uma maior peroxidação lipídica e diminuição da atividade da SOD. Nem a atividade glutationa peroxidase ou a expressão NADPH oxidase foram afetadas pelo exercício. Estes resultados sugerem que o exercício induziu alterações no estresse oxidativo de eritrócitos, que parecem estar mais associadas com a intensidade do que a duração do execicio. Além disso, nas intensidades recomendadas para a promoção da saúde, o exercício mostrou ser protetor, aumentando a atividade e a expressão de enzimas antioxidantes importantes e reduzindo os danos oxidativos.

Eritrograma, metabolismo do ferro e concentração sérica de eritropoetina em fêmeas caprinas da raça Saanen nos períodos de gestação, parto e pós-parto

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Significado da presença de esquizócitos no sangue periférico de gestantes com pré-eclâmpsia

PURPOSE: to evaluate the significance of schizocytes presence in peripheral blood smear of pregnant women with pre-eclampsia, identifying and correlating them with other markers of hemolysis and of the disease severity. METHODS: Seventh six glass slides of peripheral blood smear of pregnant women with pre-eclampsia have been evaluated. After the smear, the slides have been stained with Leishman's dye and stored till they were examined with a Leica, model DLMB microscope, provided with the Qwin Lite 2.5 software that made it possible to record the images of selected fields in CD-ROM. Ten fields with approximately 100 erythrocytes were counted in each glass slide. Schizocytes (irregular fragment or helmet-shaped, bite-shaped or triangular) were considered as present, when their percentage was equal or higher than 0.2%, their presence being correlated with other hemolysis markers (hemoglobin, total bilirubin, lactic desidrogenasis and reticulocytes), pre-eclampsia markers (proteinuria and platelet number). The Statistical Package in Social Science for Windows (SPSS), 10.0 version has been used for statistical analysis, at p<0.05. RESULTS: schizocytes have been present in 31.6% of the pregnant women with pre-eclampsia. In most (75%) of the blood smears there have been three or four schizocytes. There has been no correlation between schizocyte presence and any other hemolysis marker, any pre-eclampsia marker or disease severity. CONCLUSIONS: schizocytes have been identified in a small number and in less than a third of the pregnant women with pre-eclampsia. There has been no correlation with other hemolysis marker parameters or with the disease severity. This way, the presence of schizocytes is not a marker of the clinical evolution of pre-eclampsia.

Avaliação clínico-laboratorial de cães com doença renal crônica sob tratamento com o antioxidante N-acetilcisteína

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variáveis fisiológicas e estresse oxidativo de eqüinos durante campeonato de enduro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Perfil hematológico de búfalas da raça Murrah, criadas ao sol e à sombra, em clima tropical da Amazônia Oriental

Foram avaliadas as respostas hematológicas de 20 búfalas, criadas ao sol (grupo - SS) e à sombra (grupo - CS), em Belém, Pará. Os animais do grupo CS (n = 10) estavam em sistema silvipastoril, com Racosperma mangium e os do SS (n = 10), em piquetes sem sombra, em pastagem de Brachiaria humidicola, água para beber e sal mineral. Foram mensuradas temperatura do ar (TA), umidade relativa do ar (UR) e temperatura de globo negro, em cada tratamento. A coleta de sangue para eritrograma e número total de leucócitos foi realizada a cada 14 dias, às 13 h, durante o ano de 2009. Através da análise de variância constatou-se que em todos os períodos do ano, a TA e índice de temperatura de globo e umidade (ITGU) foram diferentes (P < 0,05), com níveis mais elevados no grupo SS. No período mais chuvoso, o grupo CS apresentou valores elevados de leucócitos, enquanto nos períodos de transição e menos chuvoso, foram maiores no grupo SS. No período menos chuvoso do ano, o grupo SS apresentou maiores valores de hemácias. O teor de hemoglobina teve maiores níveis (P < 0,05) nos períodos de transição e menos chuvoso. Somente a hemoglobina teve correlação significativa e negativa (P < 0,05) com a UR. Conclui-se que as novilhas búfalas Murrah estão sujeitas a um ambiente hostil e o período menos chuvoso é o mais propício a causar estresse térmico.

Valores hematológicos de morcegos hematófagos Desmodus rotundus (E. Geoffroy, 1810) mantidos em cativeiro

Hematological values from captive vampire bats Desmodus rotundus (E. Geoffroy, 1810). Desmodus rotundus is one of the hematophagous bat species that are responsible for significant losses to livestock and has important involvement on public health. The great interest on this bat species made it becomes the target of many investigations a required its maintenance in laboratories. Similarly to others mammals, hematological evaluation has been utilized to assess the health and morbidity state of bats, however there are scarce studies with captive bats. The aim of this study was to investigate the hypothesis that is possible to feed the vampire bat D. rotundus with frozen blood treated with citrate during a long captivity period without hematological dyscrasias. Therefore, complete blood count was performed monthly from 15 adult females kept for 345 days in cages and fed with frozen blood added to citrate. The erythrocyte concentration (9.02 ± 1.43 x1012/L), PCV (0.47 ± 0.08 L/L) and hemoglobin (163.9 ± 31.5 g/L) obtained from free-living bats (immediately after capture) were lower or similar to those obtained after 345 days of captivity, presenting erythrocytes’ count of 11.01 ± 0.82 x1012/L, packed cell volume of 0.50 ± 0.05 L/L and hemoglobin level of 158 ± 10.1 g/L. The total white blood cell (11.09 ± 6.07 x109 /L) and segmented neutrophil counts (9.85 ± 3.5 x109 /L) of free living D. rotundus decreased significantly after 345 days of captivity, with values of 3.98 ± 1.98 and 1.87 ± 978.6 x109 /L respectively, which are similar to bats from temperate regions in hibernation period. This study proved that is possible to feed D. rotundus for long periods of captivity with citrated blood without the occurrence of anemia, erythrocyte or other hematologic dyscrasia

Changes in Complete Blood Count in Patients With Surgically Treated Facial Fractures

The purpose of this prospective study was to verify the changes in the preoperative and postoperative complete blood counts of patients with surgically treated facial fractures. Fifty consecutive patients with a mean age of 34 years who presented facial fractures and underwent surgical treatment were included. A complete blood count was performed, comprising the red and white blood cell count (cells/mu L), hemoglobin (g/dL), and hematocrit (%) levels. These data were obtained preoperatively and postoperatively during a 6-week period. Statistical analyses were performed using the Kruskal-Wallis and Mann-Whitney tests to identify the possible differences among the groups and among the periods of observation using the Friedman and Wilcoxon matched-pairs signed-ranks tests. The most common location of the fractures was the mandible (42.3%), followed by the zygomatic-orbital (36.5%) and associated locations (21.2%). Leukocytosis was associated with neutrophilia in the immediate postoperative period in all of the groups. There were no values below the reference limits of the values of hemoglobin, hematocrit, and erythrocytes, and no values above the reference limits for the remaining white blood cells, although significant differences among periods were observed in most cells, depending on the type of fracture. The primary findings were leukocytosis associated with neutrophilia, verified in the immediate postoperative period in all of the groups, and the influence of the type of fracture on the significant alterations observed among studied periods on the values of hemoglobin, hematocrit, erythrocytes, leukocytes, neutrophils, and lymphocytes.

Differences in the performance of safety performance functions estimated for total crash count and for crash count by crash type

In recent years the development and use of crash prediction models for roadway safety analyses have received substantial attention. These models, also known as safety performance functions (SPFs), relate the expected crash frequency of roadway elements (intersections, road segments, on-ramps) to traffic volumes and other geometric and operational characteristics. A commonly practiced approach for applying intersection SPFs is to assume that crash types occur in fixed proportions (e.g., rear-end crashes make up 20% of crashes, angle crashes 35%, and so forth) and then apply these fixed proportions to crash totals to estimate crash frequencies by type. As demonstrated in this paper, such a practice makes questionable assumptions and results in considerable error in estimating crash proportions. Through the use of rudimentary SPFs based solely on the annual average daily traffic (AADT) of major and minor roads, the homogeneity-in-proportions assumption is shown not to hold across AADT, because crash proportions vary as a function of both major and minor road AADT. For example, with minor road AADT of 400 vehicles per day, the proportion of intersecting-direction crashes decreases from about 50% with 2,000 major road AADT to about 15% with 82,000 AADT. Same-direction crashes increase from about 15% to 55% for the same comparison. The homogeneity-in-proportions assumption should be abandoned, and crash type models should be used to predict crash frequency by crash type. SPFs that use additional geometric variables would only exacerbate the problem quantified here. Comparison of models for different crash types using additional geometric variables remains the subject of future research.

Using data mining to predict road crash count with a focus on skid resistance values

Road crashes cost world and Australian society a significant proportion of GDP, affecting productivity and causing significant suffering for communities and individuals. This paper presents a case study that generates data mining models that contribute to understanding of road crashes by allowing examination of the role of skid resistance (F60) and other road attributes in road crashes. Predictive data mining algorithms, primarily regression trees, were used to produce road segment crash count models from the road and traffic attributes of crash scenarios. The rules derived from the regression trees provide evidence of the significance of road attributes in contributing to crash, with a focus on the evaluation of skid resistance.