Seroepidemiology of Toxoplasma gondii infection in blood donors in a population from the northwestern region of São Paulo state, Brazil.

BACKGROUND: Toxoplasmosis is one of the most common parasitic infections worldwide with varying prevalence between human populations. These variations are mainly associated with human exposure to risk factors. In this article, the seroprevalence of Toxoplasma gondii infection and the risk factors associated with infection in 1729 blood donors from São José do Rio Preto, São Paulo, Brazil were analysed. METHODS: The serological tests for detecting immunoglobulin M (IgM) and immunoglobulin G (IgG) anti-T. gondii were used. The risk factors associated with the infection were identified through the application of an epidemiological questionnaire. RESULTS: The prevalence of T. gondii infection was 48.0%. The following factors were identified in the final model after multiple logistic regression analysis: drinking raw milk (p=0.003; odds ratio [OR] 1.364 [confidence interval {CI} 1.1 to 1.7]), residing in a rural area (p<0.0001; OR 2.764 [CI 1.7 to 4.6]) and receiving a blood transfusion (p=0.015; OR 1.856 [CI 1.1 to 3.0]). CONCLUSIONS: The data obtained in this study showed that the blood donor population is exposed to risk factors related to infection by T. gondii. These data allow the establishment of control programs to contribute to public health in northwestern São Paulo state.

Anti-A and anti-A,B monoclonal antisera with high titers favor the detection of A weak phenotypes.

OBJECTIVES: This study aimed to evaluate the reactivity and the titers of commercial anti-A and anti-A,B antisera in the detection of A weak antigen expression in human red blood cells. BACKGROUND: Commercial monoclonal antisera for ABO phenotyping are useful reagents allowing the identification of the four main ABO phenotypes (A, B, AB, and O). However, the reactivity of these commercial reagents can not be evident when the A or B antigens are weakly expressed, and these antisera have low titers. METHODS/MATERIALS: Six samples from blood donors and five samples from patients with ABO forward and reverse discrepant phenotyping were evaluated. The ABO phenotyping was carried out with different commercial monoclonal anti-A and anti-A,B antisera under different temperatures, using test tubes and gel column agglutination. RESULTS: Monoclonal anti-A antisera with titers less than 256 and anti-A,B with titers less than 128 failed to detect the weak expression of A antigen in 73% and 67% of the A weak phenotypes, respectively. Titres equal to or higher than 2048 (anti-A) and 1024 (anti-A,B) showed better reactivity, independent of the cell clone. CONCLUSION: Our data indicate that anti-A and anti-A,B antisera with high titers give better reactivity with red blood cells carrying A weak antigen expression.

Hematopoietic Chimera in a Male Blood Donor and His Dizygotic Twin Sister.

Twin hematopoietic chimera in humans is a phenomenon that was discovered accidentally and the prevalence of which remains unclear. The resolution of chimera cases requires studying family medical records, data analysis, and investigations of hematopoietic cells and cells from other tissues. The interactions among ABO, Lewis, and secretor histo-blood group systems are explored to resolve cases of hematopoietic chimera. Here we report a rare case of hematopoietic chimera where twins present a mixed field reaction in the ABO, Rh, and Kidd red blood cell phenotyping. Using red blood cells separated from the mixed field as well as molecular approaches and investigations of family members, we identify inconsistent genotypes with the Mendelian inheritance pattern when comparing the peripheral blood with the buccal epithelium of the male twin and his twin sister. Analysis of the ABO, Lewis, and secretor phenotypes, and genomic DNA from buccal epithelium showed the genotypes ABO*A1.01/ABO*B.01 and FUT2*01N.02/ FUT2*01N.02 in the male twin and the genotypes ABO*O.01.01/ABO*O.01.02 and FUT2*01/FUT2*01 in the female twin. The results of the HLA-DRB1 genotyping showed inconsistency between the male and his twin sister. We conclude that the serological analyses combined with molecular approaches used in this study are good tools to resolve cases of hematopoietic chimera.

Genetic and biochemical markers of hydroxyurea therapeutic response in sickle cell anemia.

BACKGROUND: Sickle cell anemia (SCA) presents a complex pathophysiology which can be affected by a number of modifying factors, including genetic and biochemical ones. In Brazil, there have been no studies verifying ßS-haplotypes effect on oxidative stress parameters. This study evaluated ßS-haplotypes and Hb F levels effects on oxidative stress markers and their relationship with hydroxyurea (HU) treatment in SCA patients. METHODS: The studied group was composed by 28 SCA patients. Thirteen of these patients were treated with HU and 15 of them were not. We used molecular methodology (PCR-RFLP) for hemoglobin S genotype confirmation and haplotypes identification. Biochemical parameters were measured using spectrophotometric methods (Thiobarbituric-acid-reactive substances and Trolox equivalent antioxidant capacity levels, catalase and GST activities) and plasma glutathione levels by High-performance liquid chromatography coupled to electrochemical detection. RESULTS: We found the highest frequency of Bantu haplotype (48.2%) which was followed by Benin (32.1%). We observed also the presence of Cameroon haplotype, rare in Brazilian population and 19.7% of atypical haplotypes. The protective Hb F effect was confirmed in SCA patients because these patients showed an increase in Hb F levels that resulted in a 41.3% decrease on the lipid peroxidation levels (r =-0.74, p=0.01). Other biochemical parameters have not shown differential expression according to patient's haplotypes. Bantu haplotype presence was related to the highest lipid peroxidation levels in patients (p < 0,01), but it also conferred a differential response to HU treatment, raising Hb F levels in 52.6% (p = 0.03) when compared with the group with the same molecular profile without HU usage. CONCLUSIONS: SCA patients with Bantu haplotype showed the worst oxidative status. However these patients also demonstrated a better response to the treatment with HU. Such treatment seems to have presented a "haplotype-dependent" pharmacological effect.

Relationship between oxidative stress, glutathione S-transferase polymorphisms and hydroxyurea treatment in sickle cell anemia.

This study evaluated the oxidative stress and antioxidant capacity markers in sickle cell anemia (SCA) patients with and without treatment with hydroxyurea. We assessed GSTT1, GSTM1 and GSTP1 polymorphisms in patients and a control group. The study groups were composed of 48 subjects without hemoglobinopathies and 28 SCA patients, 13 treated with HU [SCA (+HU)], and 15 SCA patients not treated with HU [SCA (-HU)]. We observed a significant difference for GSTP1 polymorphisms in SCA patients with the V/V genotype that showed higher glutathione (GSH) and Trolox equivalent antioxidant capacity (TEAC) (p=0.0445 and p=0.0360), respectively, compared with the I/I genotype. HU use was associated with a 35.2% decrease in the lipid peroxidation levels of the SCA (+HU) group (p<0.0001). Moreover, the SCA (+HU) group showed higher TEAC as compared to the control group (p=0.002). We did not find any significant difference in glutathione-S-transferase (GST) activity between the groups (p=0.76), but the catalase (CAT) activity was about 17% and 30% decreased in the SCA (+HU) and SCA (-HU) groups, respectively (p<0.00001). Whereas the plasma GSH levels were ~2 times higher in the SCA patients than the control group (p=0.0005). HU use has contributed to higher CAT activity and TEAC, and lower lipid peroxidation in patients under treatment. These findings may explain the influence of HU in ameliorating oxidative stress on SCA subjects.

Detecção dos anticorpos regulares abo maternos em recém-nascidos pelo método de tipagem sangüínea reversa estendida até fase de antiglobulina humana / Detection of the mother's abo regulars antibodies in newborns by the reverse blood typing

Neste estudo foram definidos os índices de detecção dos anticorpos regulares ABO maternos em recém-nascidos pelo método de tipagem sangüínea reversa estendida até fase de antiglobulina humana (TRAGH) e a relação destes resultados com os achados de outras metodologias envolvidas no diagnóstico da incompatibilidade materno-fetal pelo sistema ABO (IABO). Foram colhidasamostras sangüíneas para análise imuno-hematológica de 38 recém-nascidos com tipo sangüíneo A ou B, apresentando até 30 dias de vida (sem conhecimento prévio dos fenótipos ABO maternos) e realização dos testes de tipagem ABO direta, TRAGH, Coombs direto e eluato-LUI, visando detectar anti-A e/ou anti-B. Os resultados demonstraram que a TRAGH efetuou a detecção dos anticorpos regulares ABO maternos na maioria das amostras analisadas nas quais foram confirmados os casos de IABO (09 de 15 amostras), constituindo-se, mediante a análise conjunta com os demais dados imuno-hematológicos, em um útil parâmetro laboratorial na adequação imunológica do hemocomponente ao receptor ena confirmação diagnóstica de IABO.

In this study were defined the exponents of the detection of mother’s ABO regulars antibodies in newborns by the reverse blood typing extend up to stage of the antihuman globulin method (RTAGH) and the relacion this results with the faind other methods include in the diagnosis of the ABO maternal-fetal incompatibility (IABO). Samples of blood were picked for immunohematology analysis from 38 newborns with the blood type A our B , with until 30 days of life ( without previous knowing of the ABO mother’s types) and make of the ABO typing direct, RTAGH, Coombs direct and elution by freezing tests, purposing the detection of the anti-A and/our anti-B. The results demonstrate with the RTAGH maked the detection of the mother’s ABO regulars antibodies in the most samples analyses with the were confirmated the cases of the IABO (09 of 15 samples), constitute, trough the completeness analyse with too much tests immunohematology, in the useful laboratory information in the imunology adjust of the hemocomponent to the pacient and in the diagnosis of IABO confirmation.

Atypical chromosome abnormalities in acute myeloid leukemia type M4

This study reports an adult AML-M4 patient with atypical chromosomal aberrations present in all dividing bone marrow cell at diagnosis: t(1;8)(p32.1;q24.2), der(9)t(9;10)(q22;?), and ins(19;9)(p13.3;q22q34) that may have originated transcripts with leukemogenic potential.

Frequency of the BCR/ABL rearrangements and associated alterations detected by FISH during monitoring of patients taking imatinib mesylate in isolation / Freqüência do rearranjo BCR/ABL e alterações associadas detectadas por FISH no monitoramento de pacientes em uso exclusivo do mesilato de imatinibe

The introduction of imatinib mesylate as treatment of chronic myelogenous leukemia has saved many patients, but the success of therapy is hampered by resistance and possible non-destruction of the malignant clone. This article describes the cytogenetic responses and abnormal cytogenetic patterns involving the ABL and BCR genes detected by FISH in patients who use exclusively imatinib. The results showed that other alterations involving the BCR and ABL genes do not seem to be related to resistance to the drug as they occur in low frequencies and can not be associated to the cytogenetic response or to the time of treatment. Moreover, the response to imatinib seems to be individual and unpredictable, independent of the time of treatment and of its initiation after diagnosis.

A introdução do mesilato de imatinibe como tratamento da leucemia mielóide crônica tem salvado muitos pacientes, mas o sucesso da terapia tem sido prejudicado pela resistência e possível não destruição do clone maligno. Este artigo descreve a resposta citogenética e padrões citogenéticos anormais envolvendo os genes ABL e BCR detectados por FISH em pacientes em uso exclusivo de imatinibe. Os resultados mostraram que outras alterações envolvendo os genes BCR e ABL não parecem estar relacionadas à resistência à droga, elas ocorrem em baixas freqüências e podem não estar associadas à resposta citogenética ou ao tempo de tratamento. Contudo, a resposta ao imatinibe parece ser individual e imprevisível, independente do tempo e do início do tratamento após o diagnóstico.

Análise do rearranjo BCR/ABL por bandamento GTG e FISH: comparação das freqüências ao diagnóstico da LMC / Analysis of the BCR/ABL rearrangement by GTG banding and FISH: A comparison of frequencies at diagnosis of CML

A Leucemia Mielóide Crônica (LMC) é uma doença mieloproliferativa clonal caracterizada pela presença do cromossomo Philadelphia (Ph). Este cromossomo é resultante de uma translocação t(9;22) (q34;q11) que justapõe os genes BCR e ABL. A detecção do cromossomo Ph e/ou do rearranjo BCR/ABL, uma vez que este último é submicroscópico em alguns casos, é fundamental, pois não somente contribui para transformação leucêmica, mas também interfere no sucesso do tratamento. Sua detecção é, portanto, fundamental para o diagnóstico, prognóstico e terapêutica. Este trabalho teve como objetivos estudar a freqüência do cromossomo Ph ou rearranjo BCR/ABL nas células da medula óssea de pacientes portadores de LMC ao diagnóstico, com uso das técnicas de bandamento GTG e FISH, e comparar os resultados obtidos com as duas técnicas. O cromossomo Ph e o rearranjo foram observados em 100 dos casos analisados nas diferentes técnicas.Em alguns casos a freqüência do cromossomo Ph, detectado por GTG foi maior do que a do rearranjo molecular BCR/ABL detectada por FISH. A técnica de FISH também identificou alterações inespecíficas envolvendo os genes BCR e/ou ABL. Ambas as técnicas foram fundamentais para os resultados obtidos e, portanto, devem ser usadas como complementares na análise de células da medula óssea de pacientes com LMC ao diagnóstico

Hemofilias e doenças de von Willembrand: aspectos clínicos e marcadores de infecçöes transfusionais / Von Willlebrand's disease and hemophilias: clinical aspects and bloodmarkers of transfusional infections

Estudamos retrospectivamente 48 casos de coagulopatias hereditárias, clientes do ambulatório da Faculdade de Medicina de Sao José do Rio Preto, provenientes da cidade e regiao. Encontramos predominância da deficiência de fator VIII e raros casos diagnosticados como doença de von Willebrand. História familiar está presente numa minoria dos casos. A média das idades foi de 17,9 anos e a do aparecimento das primeiras manifestaçoes hemorrágicas, de 2,3. Hematomas foram a manifestaçao mais frequente. A contaminaçao com Hepatites C, B, HIV e Chagas foi de 56 por cento dos casos, sendo que acima de 50 por cento dos pacientes estao presumivelmente em atividade sexual, colocando seus parceiros sob risco. Sequelas ortopédicas estao presentes em 41,67 por cento dos casos. Como causa de morte, a maioria foi devida a hemorragias maciças, sendo que os cuidados hemoterápicos foram considerados insuficientes. Anemia ferropriva está presente em 20 por cento dos casos, exigindo pronto diagnóstico, tratamento e profilaxia. Um terço dos casos sao crianças abaixo de 10 anos de idade, sem ou com poucas sequelas e soronegativos, exigindo cuidados especiais. Evitar as manifestaçoes presentes nos mais idosos e melhorar a qualidade de vida atrvés do aporte de quantidade adequada de fatores e pessoal treinado para usá-lo corretamente, através de equipe multidisciplinar, é nosso objetivo imediato.

Traço falcêmico associado à hemoglobinúria noturna paroxística / Sickling trace associate with paroxysmal nocturnal hemoglobinuria

Os autores apresentam um caso de falcemia heterozigota (Hb AS) associada a hemoglobinúria noturna paroxística (HNP). Várias patologias podem estar associadas com HNP; nesses ultimos cinco anos a literatura científica relatou apenas um caso de associaçäo entre HNP e hemoglobinopatia - a Hb SS. O caso estudado apresentou anemia grave, pancitopenia, hemoglobinúria e medula hipocelular que mostrou-se responsiva ao ácido fólico. O quadro laboratorial se destaca pela anemia grave (Hb: 5,2 g/dl), hipoferremia, testes de Ham e da glicose positivos, e presença de Hb AS