Marilda de Souza Gonçalves

Prevalence of homozygosity for the deleted alleles of glutathione S-transferase mu (GSTM1) and theta (GSTT1) among distinct ethnic groups from Brazil: relevance to environmental carcinogenesis?

Arruda VR, Grignolli CE, Goncalves MS, Soares MC, Menezes R, Saad STO, Costa FF. Prevalence of homozygosity for the deleted alleles of glutathione S‐transferase mu (GSTMl) and theta (GSTTl) among distinct ethnic groups from Brazil: relevance to enviromental carcinogenesis? Clin Genet 1998: 54: 210–214. 0 Munksgaard, 1998

Frequency of infection of Lutzomyia phlebotomines with Leishmania braziliensis in a Brazilian endemic area as assessed by pinpoint capture and polymerase chain reaction.

Leishmania infected of Lutzomyia spp. are rare in endemic areas. We tested the hypothesis that there is clustering of infected vectors by combining pinpoint capture with sensitive L. braziliensis kDNA minicircle specific PCR/dot blot in an endemic area in the State of Bahia. Thirty out of 335 samples (10 to 20 sand flies/sample; total of 4,027 female sand flies) were positive by PCR analysis and dot blot leading to a underestimated overall rate of 0.4% positive phlebotomines. However, 83.3% of the positive samples were contributed by a single sector out of four sectors of the whole studied area. This resulted in a rate of 1.5% Leishmania positive phlebotomines for this sector, far above rates of other sectors. Incidence of American cutaneous leishmaniasis cases for this sector was about twice that for other sectors. Our results show that there is a non-homogeneous distribution of Leishmania-infected vectors. Such a clustering may have implications in control strategies against leishmaniasis, and reinforces the necessity of understanding the ecological and geographical factors involved in leishmanial transmission.

Hemoglobinopathies in newborns from Salvador, Bahia, Northeast Brazil

Hemoglobinopathies are hereditary disorders of the hemoglobin molecule with a high prevalence worldwide. Brazil has a prevalence of 0.1 to 0.3% of newborns with sickle cell anemia and 20.0 to 25.0% of heterozygous alpha2 thalassemia among African Brazilians. In the present study, we investigated the presence of variant hemoglobins and alpha2(3.7 Kb) and alpha2 (4.2 Kb) thalassemia in newborns from Salvador, Bahia, Brazil. Samples of umbilical cord blood from a total of 590 newborns were analyzed, of which 57 (9.8%) were FAS; 36 (6.5%) FAC; one (0.2%) SF; and five (0.9%) FSC. One hundred fourteen (22.2%) newborns had alpha2(3.7 Kb) thalassemia, of whom 101 (19.7%) were heterozygous and 13 (2.5%) homozygous, showing statistical significance for hematological data between newborns with normal alpha genes and alpha2(3.7 Kb) thalassemia carriers. The alpha2(4.2 Kb) thalassemia was not found. Frequencies found in the present study confirm that hemoglobinopathies are a public health problem in Brazil, emphasizing the need for neonatal screening and genetic counseling programs.

ßS-Haplotypes in sickle cell anemia patients from Salvador, Bahia, Northeastern Brazil

BetaS-Globin haplotypes were studied in 80 (160 betaS chromosomes) sickle cell disease patients from Salvador, Brazil, a city with a large population of African origin resulting from the slave trade from Western Africa, mainly from the Bay of Benin. Hematological and hemoglobin analyses were carried out by standard methods. The betaS-haplotypes were determined by PCR and dot-blot techniques. A total of 77 (48.1%) chromosomes were characterized as Central African Republic (CAR) haplotype, 73 (45.6%) as Benin (BEN), 1 (0.63%) as Senegal (SEN), and 9 (5.63%) as atypical (Atp). Genotype was CAR/CAR in 17 (21.3%) patients, BEN/BEN in 17 (21.3%), CAR/BEN in 37 (46.3%), BEN/SEN in 1 (1.25%), BEN/Atp in 1 (1.25%), CAR/Atp in 6 (7.5%), and Atp/Atp in 1 (1.25%). Hemoglobin concentrations and hematocrit values did not differ among genotype groups but were significantly higher in 25 patients presenting percent fetal hemoglobin (%HbF) > or = 10% (P = 0.002 and 0.003, respectively). The median HbF concentration was 7.54+/-4.342% for the CAR/CAR genotype, 9.88 3.558% for the BEN/BEN genotype, 8.146 4.631% for the CAR/BEN genotype, and 4.180+/-2.250% for the CAR/Atp genotype (P = 0.02), although 1 CAR/CAR individual presented an HbF concentration as high as 15%. In view of the ethnic and geographical origin of this population, we did not expect a Hardy-Weinberg equilibrium for CAR/CAR and BEN/BEN homozygous haplotypes and a high proportion of heterozygous CAR/BEN haplotypes since the State of Bahia historically received more slaves from Western Africa than from Central Africa.

Clinical, hematological, and molecular characterization of sickle cell anemia pediatric patients from two different cities in Brazil.

This study focused on clinical, hematological, and molecular aspects of sickle cell anemia pediatric patients from two different cites in Brazil. Seventy-one patients from São Paulo and Salvador, aged 3 to 18 years, were evaluated. Hematological analyses, betaS globin gene haplotypes, and alpha2 3.7kb-thalassemia were performed. Numbers of hospitalizations due to vaso-occlusive crises, infections, stroke, and cholelithiasis were investigated. São Paulo had more hospitalizations from vaso-occlusion, cholelithiasis, and stroke than Salvador. The Ben/CAR genotype predominated in both cities. Alpha2 3.7kb-thalassemia had a frequency of 28.2% in Salvador, mostly with Ben/CAR genotype (45.0%), while São Paulo had 22.5% with similar frequencies of the Ben/ CAR and CAR/CAR genotypes. Sickle cell anemia patients from São Paulo also had more episodes of stroke, which was observed among CAR/CAR, atypical, and BEN/CAR haplotypes. In Salvador stroke was only observed in the Ben/CAR genotype. Cholelithiasis had similar frequencies in the two cities. These data suggest a milder phenotype among patients in Salvador, possibly due to genetic, environmental, and socioeconomic factors. Further studies are needed to elucidate modulating factors and phenotype association.

Clinical and molecular characteristics of sickle cell anemia in the northeast of Brazil

Beta S-globin gene (βS-globin) haplotypes, markers for severe sickle cell anemia (SCA), and the alpha-thalassemia 2 gene 3.7 kb deletion (-α2 3.7 kb thal) along with demographic and clinical data were investigated in SCA outpatients (n = 125, 63 female and 62 male) in the Brazilian state of Bahia, which has a high prevalence SCA. PCR-RFLP showed that the Central African Republic/Benin (CAR/BEN, 51.2%) haplotype was most frequent, followed by the Benin/Benin (Ben/Ben, 28.8%). At least one CAR haplotype was present in every outpatient with a history of cerebrovascular accident. The Cameroon (Cam), Senegal (Sen) and Arab-India haplotypes occurred in small numbers, as did atypical haplotypes. Fetal hemoglobin (HbF, %) was unevenly distributed. Compared to those > 18 y, those aged ≤ 18 y had had fewer erythrocyte transfusions and high HbF levels (12.3% ± 7.01 to 7.9% ± 4.36) but a higher frequency of spleen sequestration and pneumonia. Compared with normal α - genes carriers values, the outpatients with -α2 3.7 kb thal (determined by PCR analysis) had significantly higher mean hemoglobin concentration (Hb) (8.3 ± 1.34 g/dL, p = 0.018) and packed cell volume (PCV = 27.1% ± 4.26, p = 0.019) but low mean corpuscular volume (MCV = 86.1 fL = 10-15 L ± 9.56, p = 0.0004) and mean corpuscular hemoglobin (MCH = 26.6% ± 4.60, p = 0.039).

Association between the Haptoglobin and Heme Oxygenase 1 Genetic Profiles and Soluble CD163 in Susceptibility to and Severity of Human Malaria

ABSTRACT Intravascular hemolysis is a hallmark event in the immunopathology of malaria that results in increased systemic concentrations of free hemoglobin (Hb). The oxidation of Hb by free radicals causes the release of heme, which amplifies inflammation. To circumvent the detrimental effects of free heme, hosts have developed several homeostatic mechanisms, including the enzyme haptoglobin (Hp), which scavenges cell-free Hb, the monocyte receptor CD163, which binds to Hb-Hp complexes, and heme oxygenase-1 (HO-1), which degrades intracellular free heme. We tested the association between these three main components of the host response to hemolysis and susceptibility to malaria in a Brazilian population. The genetic profiles of the HMOX1 and Hp genes and the plasma levels of a serum inflammatory marker, the soluble form of the CD163 receptor (sCD163), were studied in 264 subjects, including 78 individuals with symptomatic malaria, 106 individuals with asymptomatic malaria, and 80 uninfected individuals. We found that long (GT)n repeats in the microsatellite polymorphism region of the HMOX1 gene, the Hp2 allele, and the Hp2.2 genotype were associated with symptomatic malaria. Moreover, increased plasma concentrations of heme, Hp, HO-1, and sCD163 were associated with susceptibility to malaria. The validation of these results could support the development of targeted therapies and aid in reducing the severity of malaria.

Interleukin 8 as a vaso-occlusive marker in Brazilian patients with sickle cell disease

Sickle cell disease has a worldwide distribution and is a public health problem in Brazil. Although vaso-occlusive crisis (VOC) is one of the most important clinical features of the disease, there are still several steps of its pathogenesis which are unknown. The increase of the chemotactic factor interleukin 8 (IL-8) has been reported to be involved in sickle cell disease crisis, but this has not been demonstrated conclusively. In the present study we analyzed serum IL-8 levels by ELISA and hematological parameters and hemoglobin patterns by standard techniques in 23 (21 SS and 2 SC) Brazilian patients with sickle cell syndromes during VOC caused by different inducing factors, 22 (21 SS and 1 SC) sickle cell patients out of crisis, and 11 healthy controls. Increased IL-8 levels were observed in 19 of 23 VOC patients (79.2%), 3 of them with more than 1,000 pg/ml. Seventeen of 22 (77.3%) non-crisis patients showed low IL-8 levels (less than 15 pg/ml). Healthy controls had low IL-8 levels. A significant difference in serum IL-8 levels was observed between crisis and non-crisis sickle cell patients (P<0.0001). There was no correlation between IL-8 levels and hematological data or hemoglobin patterns. High serum IL-8 levels were observed in VOC patients independently of the crisis-inducing factor. We conclude that in the studied population, IL-8 concentration may be a useful VOC marker, although the mechanism of the pathogenic process of sickle cell VOC syndromes remains unclear.

Tracing the origin of Brazilian HTLV-1 as determined by analysis of host and viral genes.

We compared the genetic diversity of the Brazilian human T-cell lymphotropic virus type 1 isolates with those found in KwaZulu–Natal (KZN), South Africa, and with the genetic background of the hosts. The seroprevalence rate in KZN was 1.7%. All sequences belonged to the A subgroup. The presence of South African sequences in two different clusters from Brazil, and the finding of the βA-globin haplotype in infected hosts are consistent with the transmission of this virus from southern Africa to Brazil.

The beta-globin gene cluster haplotypes in sickle cell anemia patients from Northeast Brazil: a clinical and molecular view.

The βS‐globin haplotypes were studied in 78 sickle cell Brazilian patients from Bahia, Northeast Brazil, that has a large population of African origin. Hemoglobin (Hb) profiles were developed by high‐performance liquid chromatography (HPLC), and βS‐globin gene haplotypes were determined by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) techniques. We identified 44 (55.0%) patients with the CAR/Ben (Central African Republic/Benin) genotype, 16 (20.0%) Ben/Ben, 13 (16.2%) CAR/CAR and seven (8.8%) with other genotypes. Analyses of the phenotypes showed clinical differences related only to Hb F levels and blood transfusion therapy; the presence of − α− 3.7‐thalassemia (thal) demonstrated statistical significance when associated with hematocrit (p = 0.044), MCV (p = 0.0007), MCH (p = 0.012) and spleen sequestration events. The haplotype diversity found in the present study can be justified by information about the origin of the slave traffic period in Bahia during the 19th century. The specific characteristics described among the Bahian sickle cell patients could be confirmed by increasing the number of patients with specific genotypes and further studies of genetic markers.