Perfis hematológico e bioquímico de ratos (Rattus norvegicus) mantidos sob sistema de ventilação microambiental

Previous studies reported that rats (Rattus norvegicus) kept under microenvironmental ventilation systems (MEV) present better productive and health parameters when compared to animals kept under general diluting ventilation (GDV). The objective of the present research trial was to evaluate hematological and biochemical profiles of rats kept under MVS. In order to achieve this objective, two different trials were designed: Trail 1 (E1), in which it was evaluated the reproductive performance of males and females submitted to two different air speed limits - FV1, from 0.03 to 0.26 m / sec and FV2, from 0.27 to 0.80 m / sec. In Trial 2 (E2) it was evaluated different bed change intervals (3, 5, 7 and 9 days), for males kept under constant air speed (0.5 m / sec). Values for hemogram and biochemical patterns of these animals were compared to those of rats kept under GDV. Results show statistical differences in some of the studied parameters not only for the comparison between GVD and E1 and GVD and E2, but also between both groups submitted to MEV (E1 and E2). However, values found for all studied parameters are inside the normal range reported for this species, what indicates that MEV does not induce important changes in the physiological parameters evaluated.Em estudos anteriores, demonstrou-se que ratos mantidos em sistema de Ventilação Microambiental (VMA) apresentaram parâmetros de produtividade e padrão sanitário melhores do que aqueles mantidos em sistema de Ventilação Geral Diluidora (VGD). Outra etapa dos experimentos foi determinar os parâmetros fisiológicos destes animais. O presente estudo foi realizado para avaliar os perfis hematológico e bioquímico de ratos mantidos sob o sistema de VMA. Para tanto, foram realizados dois experimentos diferentes, com ratos mantidos em VMA, quais sejam: Experimento 1 (E1), no qual foi avaliado o desempenho reprodutivo de machos e fêmeas, sob duas faixas de velocidade de ar (FV1 - de 0,03 a 0,26 m/s, e FV2 - de 0,27 a 0,80 m/s); Experimento 2 (E2), no qual foram avaliados diferentes intervalos de troca de cama (3, 5, 7 e 9 dias), para ratos machos mantidos a uma velocidade de ar constante de 0,5 m/s. Os valores do hemograma e de parâmetros bioquímicos destes animais foram comparados com os valores encontrados em ratos mantidos sob VGD. Os resultados obtidos demonstraram diferenças estatísticas em alguns dos parâmetros observados, tanto entre os sistemas VGD e VMA, como entre os diferentes grupos de VMA. Contudo, os valores encontrados em todos os parâmetros avaliados encontram-se dentro de faixas de variação normal para a espécie estudada, como é descrito na literatura. Isto indica que o emprego do sistema de VMA não induz alterações relevantes nos parâmetros fisiológicos estudados

Pesquisa de hemólise intravascular na forma cutânea de loxoscelismo

Haptoglobin assay, a highly sensitive method to detect intravascular hemolysis was carried out in the sera of 19 patients referred to Hospital Vital Brazil with the cutaneous form of loxoscelism in order to investigate the occurrence of mild intravascular hemolysis. Data from this series did not show decreased levels haptoglobin, ruling out intravascular hemolysis in these patients with cutaneous form of loxoscelism.Dezenove pacientes que apresentaram a forma clínica cutânea do loxoscelismo foram investigados com o propósito de pesquisar hemólise intravascular sub-clínica, lançando mão da dosagem de haptoglobina, um método altamente sensível que permite detectar discreta presença de hemólise intravascular. Não foi encontrada diminuição de haptoglobina, o que descarta uma ação hemolítica do veneno da Loxosceles nestes pacientes

Red cell aspartate aminotransferase saturation with oral pyridoxine intake

CONTEXT AND OBJECTIVE: The coenzyme of aspartate aminotransferase is pyridoxal phosphate, generated from fresh vegetables containing pyridoxine. Vitamin B6-responsive sideroblastic anemia, myelofibrosis and Peyronie’s syndrome respond to high pyridoxine doses. The objective was to investigate the oral pyridoxine oral dose that would lead to maximized pyridoxal phosphate saturation of red cell aspartate aminotransferase. DESIGN AND SETTING: Controlled trial, in Hematology Division of Instituto Adolfo Lutz. METHODS: Red cell aspartate aminotransferase activity was assayed (before and after) in normal volunteers who were given oral pyridoxine for 15-18 days (30 mg, 100 mg and 200 mg daily). In vitro study of blood from seven normal volunteers was also performed, with before and after assaying of aspartate aminotransferase activity. RESULTS: The in vivo study showed increasing aspartate aminotransferase saturation with increasing pyridoxine doses. 83% saturation was reached with 30 mg daily, 88% with 100 mg, and 93% with 200 mg after 20 days of oral supplementation. The in vitro study did not reach 100% saturation. CONCLUSIONS: Neither in vivo nor in vitro study demonstrated thorough aspartate aminotransferase saturation with its coenzyme pyridoxal phosphate in red cells, from increasing pyridoxine supplementation. However, the 200-mg dose could be employed safely in vitamin B6-responsive sideroblastic anemia, myelofibrosis and Peyronie’s syndrome treatment. Although maximum saturation in circulating red cells is not achieved, erythroblasts and other nucleated and cytoplasmic organelles containing cells certainly will reach thorough saturation, which possibly explains the results obtained in these diseases

Is automated platelet counting still a problem in thrombocytopenic blood?

CONTEXT: Reliable platelet counting is crucial for indicating prophylactic platelet transfusion in thrombocytopenic patients. OBJECTIVE: To evaluate the precision and accuracy of platelet counting for thrombocytopenic patients, using four different automated counters in comparison with the Brecher & Cronkite reference method recommended by the International Committee for Standardization in Hematology (ICSH). TYPE OF STUDY: Automated platelet counting assessment in thrombocytopenic patients. SETTING: Hematology Laboratory, Hospital do Servidor Público Estadual de São Paulo, and the Hematology Division of Instituto Adolfo Lutz, São Paulo, SP, Brazil. MAIN MEASUREMENTS: Brecher & Cronkite reference method and four different automated platelet counters. PARTICIPANTS: 43 thrombocytopenic patients with platelet counts of less than 30,000/µl RESULTS: The ADVIA-120 (Bayer), Coulter STKS, H1 System (Technicom-Bayer) and Coulter T-890 automatic instruments presented great precision and accuracy in relation to laboratory thrombocytopenic samples obtained by diluting blood from normal donors. However, when thrombocytopenic patients were investigated, all the counters except ADVIA (which is based on volume and refraction index) showed low accuracy when compared to the Brecher & Cronkite reference method (ICSH). The ADVIA counter showed high correlation (r = 0.947). However, all counters showed flags in thrombocytopenic samples. CONCLUSION: The Brecher & Cronkite reference method should always be indicated in thrombocytopenic patients for platelet counts below 30,000 plt /µl obtained in one dimensional counters

Enzymes and membrane proteins of ADSOL-preserved red blood cells

CONTEXT: The preservative solution ADSOL (adenine, dextrose, sorbitol, sodium chloride and mannitol) maintains red cell viability for blood trans-fusion for 6 weeks. It would be useful to know about its preservation qualities over longer periods. OBJECTIVE: To determine some red cell biochemical parameters for peri-ods of up to 14 weeks in order to determine whether the red cell metabo-lism integrity would justify further studies aiming at increasing red cell preservation and viability. DESIGN: Biochemical evaluation designed to study red cell preservation. SETTING: São Paulo University erythrocyte metabolism referral center. SAMPLE: Six normal blood donors from the University Hospital of the Universidade Federal do Paraná, Curitiba, Brazil. MAIN MEASUREMENTS: Weekly assay of erythrocyte adenosine-5´-triphosphate (ATP), 2,3-diphosphoglycerate (2,3DPG), hexokinase (HX), phosphofructokinase (PFK), pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G-6-PD), 6-phosphogluconic dehydrogenase (6-PGD), glyceraldehyde-3-phosphate dehydrogenase (GAPD), glutathione reduc-tase (GR), glutathione peroxidase (GSHPx), plasma sodium and potas-sium, blood pH, and membrane proteins of red cells preserved in ADSOL were studied during storage for 14 weeks storage. RESULTS: During ADSOL preservation, erythrocyte ATP concentration decreased 60% after 5 weeks, and 90% after 10 weeks; the pH fell from 6.8 to 6.4 by the 14th week. 2,3-DPG concentration was stable during the first week, but fell 90% after 3 weeks and was exhausted after 5 weeks. By the end of the 5th week, an activity decrease of 16-30% for Hx, GAPD, GR, G-6-PD and 6-PGD, 35% for PFK and GSHPx, and 45% for PK were observed. Thereafter, a uniform 10% decay was observed for all enzymes up to the 14th week. The red blood cell membrane pro-teins did not show significant alterations in polyacrylamide gel electro-phoresis (SDS-PAGE) during the 14 weeks. CONCLUSION: Although the blood viability was shown to be poor from the 6th week up to the 14th week of storage due to ATP and 2,3-DPG depletion, the other biochemical parameters remained in fairly good condition for longer storage. As there is a gradual and uniform decay in activity throughout these 14 weeks, it seems that ADSOL-preserved red cells may be used as red cell enzyme standards and membrane proteins as well

Normal erythrocyte calpain I activity on membrane proteins under near-physiological conditions in patients with essential hypertension

CONTEXT: It has been reported that the equilibrium between the erythrocyte protease calpain I and its physiological inhibitor calpastatin is disrupted in patients with essential hypertension. OBJECTIVE: To investigate the activity of non-purified calpain I in hemolysates against the erythrocytic membrane proteins, rather than against other substrates. DESIGN: Evaluation of calpain I red cell activity upon its own physiological substrates in hypertensive patients, in a near-physiological environment. SETTING: LIM-23 and LIM-40 of Hospital das Clinicas of the Faculty of Medicine of USP. SAMPLE: Patients with moderate primary hypertension over 21 years of age who were given amlodipine (n:10) and captopril (n:10) for 8 weeks, plus normal controls (n:10). MAIN MEASUREMENTS: Red cell membrane proteins were incubated with and without protease inhibitors and with and without calcium chloride and underwent polyacrylamide gel electrophoresis. RESULTS: Digestion of bands 2.1 and 4.1 was observed, indicating calpain I acitivity. No statistical differences regarding bands 2.1 and 4.1 were observed before treatment, between the controls and the hypertensive patients, either in ghosts prepared without calcium or with increasing concentrations of calcium. Nor were statistical differences observed after treatment, between the controls and the patients treated with amlodipine and captopril, or between the patients before and after treatment with both drugs. CONCLUSION: The final activity of non-purified calpain I upon its own physiological substrate, which was the approach utilized in this study, may more adequately reflect what happens in red cells. Under such conditions no imbalance favoring calpain I activity increase was observed. The protective factor provided by calpastatin against calpain I activity may diminish under hypertension

Meta-hemoglobinemia associada ao loxoscelismo

Vinte e cinco pacientes que apresentaram a forma cutânea do loxoscelismo foram estudados após a picada, determinando-se a glicose-6-fosfato desidrogenase, glutationa redutase e glutationa peroxidase eritrocitárias, haptoglobina e latico desidrogenase séricas, bilirrubina, reticulócitos e meta-hemoglobina. Não foi observada hemólise aumentada, mas foi detectado aumento da meta-hemoglobina em 54% dos casos: em 7% entre 1,1% e 2%, em 27% variou de 2,1% a 4%, e em 20% de 4,1 a 8%. Amostras de sangue de um indivíduo normal do grupo 0 de uma paciente que exibiu meta-hemoglobina após picada por Loxosceles foram incubadas separadamente com anti-soros contra Loxosceles gancho, Crotalus terrificus e Bothrops jararaca, com veneno de Loxosceles gaucho e fenol a 3%, e não se detectou aumento de meta-hemoglobina depois de 1, 4, 8 e 15 dias em todas as amostras. Por ocasião do 25º dia, todas as amostras, inclusive os controles, exibiram discreta diminuição da atividade da meta-hemoglobina redutase. Os dados sugerem que a meta-hemoglobina que ocorreu em 54% dos pacientes provavelmente decorreu do metabolismo do veneno, uma vez que o veneno in natura não induziu meta-hemoglobinemia.In twenty five patients who presented the cutaneous form of loxoscelism, serum haptoglobin and lactic dehydrogenase, erythrocyte glucose-6-phosphate dehydrogenase, glutathione reductase, glutathione peroxidase, methemoglobin, bilirubin and reticulocytes were investigated after bite. No hemolysis was detected but an increase in methemoglobin was found in 54% of the cases; in 7% it was between 1.1% and 2%, in 27% it ranged from 2.1% to 4%, and in 20% from 4.1% to 8%. Blood samples of a normal, blood group 0 individual and of a patient who exhibited methemoglobinemia after Loxosceles bite were incubated separately with antisera against Loxosceles gaucho, Crotalus terrificus, Bothrops jararaca, with Loxosceles gaucho venom and 0.3% phenol. No methemoglobin was found after 1, 4,8 and 15 days in both sets of samples. At the 25th day all the samples, including the controls, exhibited similar methemoglobin reductase decrease. The data suggest that the methemoglobinemia which occurs in 50% of the patients probably arises from in vivo venom metabolism, inasmuch as the crude venom does not induce methemoglobinemia