Consulta: creatorFacets:"Guerreiro,João Farias"
Registros recuperados: 9
Data/hora: 11/06/2024 10:17:05

Prevalence of hereditary risk factors for thrombophilia in Belém, Brazilian Amazon
Provedor de dados: 74
Autores: Yoshioka,France Keiko Nascimento; Araújo,Amélia Góes; Tavella,Marli Haydee; Hamoy,Igor Guerreiro; Guerreiro,João Farias.
Different risk factors for venous thromboembolism (VTE) have been identified, including hereditary abnormalities in the mechanisms of coagulation and fibrinolysis. We investigated five genetic polymorphisms (FVL G1691A, FII G20210A, MTHFR C677T, TAFI A152G and TAFI T1053C) associated with VTE in individuals from the city of Belém in the Brazilian Amazon who had no history of VTE. No significant difference was found between the observed and expected genotype frequencies for the loci analyzed. We found high frequencies of MTHFR C677T (33.9%) and TAFI T1053C (74%) and low frequencies of FVL (1.6%), FII G20210A (0.8%) and TAFI A152G (0.8%). The FVL G1691A, FII G20210A and MTHFR C677T frequencies were similar to those for European populations and populations of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Factor V Leiden; Prothrombin; MTHFR; TAFI; Thrombophilia.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000100007

Genetical-demographic data from two amazonian populations composed of descendants of african slaves: Pacoval and Curiau
Provedor de dados: 74
Autores: Guerreiro,João Farias; Ribeiro-dos-Santos,Ândrea Kely Campos; Santos,Eduardo José Melo dos; Vallinoto,Antonio Carlos Rosário; Cayres-Vallinoto,Izaura Maria Vieira; Aguiar,Gilberto Ferreira de Souza; Santos,Sidney Emanuel Batista dos.
The Amazon region of Brazil includes communities founded by escaped slaves, some of which still remain relatively isolated. We studied two such Afro-Brazilian communities (Pacoval and Curiau), in the rural area of Alenquer, Pará, and in the metropolitan region of Macapá, Amapá, respectively. Among 12 blood loci, alleles considered as markers of African ancestry, such as HBB*S, HBB*C, TF*D1, HP*2M, ABO*B, RH*D-, and CA2*2 were found at frequencies that are expected for populations with a predominantly African origin. Estimates of interethnic admixture indicated that the degree of the African component in Curiau (74%) is higher than that of Pacoval (44%); an Amerindian contribution was not detected in Curiau. Estimated values of African ancestry fit well...
Tipo: Info:eu-repo/semantics/article
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200004

Molecular genotyping of G6PD mutations and Duffy blood group in Afro-descendant communities from Brazilian Amazon
Provedor de dados: 74
Autores: Oliveira,Haiala S. Silva de; Silva,Aylla N. Lima Martins da; Andrade,Gabriela Barreto; Gaia,Karoline Coelho; Costa,Greice de Lemos Cardoso; Santos,Ândrea K. Campos Ribeiro dos; Guerreiro,João Farias.
Abstract Glucose-6-phosphate dehydrogenase deficiency (G6PDd) and Duffy-negative blood group are two red blood cells variants that confer protection against malaria. In this study, the distribution of the most common G6PD variants (G6PD*A-, GGPD*A and G6PD Mediterranean) and the major alleles of the Duffy blood group (FY*A, FY*B and FY*BES) were investigated in an Afro-descendant population from state of Pará, Brazilian Amazon. G6PD variants and Duffy blood group alleles were determined by TaqMan SNP genotyping assay. Overall, molecular genotyping revealed the presence of G6PD variants in 126 (24%) of the individuals studied (5% male and 19% female), and frequencies of the G6PD*A- and G6PD*A alleles were 0.061 and 0.104, respectively. Duffy blood group...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: G6PD mutations; Duffy blood group; Afro-descendants; Brazilian Amazon.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000500758

Origin of the hemoglobin S gene in a northern Brazilian population: the combined effects of  slave trade and internal migrations
Provedor de dados: 74
Autores: Pante-de-Sousa,Gabriella; Mousinho-Ribeiro,Rita de Cassia; Santos,Eduardo José Melo dos; Zago,Marco Antonio; Guerreiro,João Farias.
We analyzed DNA polymorphisms in the &lt;FONT FACE="Symbol"&gt;b&lt;/font&gt;-globin gene cluster of 30 sickle cell anemia patients from Belém, the capital city of the State of Pará, in order to investigate the origin of the &lt;FONT FACE="Symbol"&gt;b&lt;/font&gt;S mutation. Sixty-seven percent of the &lt;FONT FACE="Symbol"&gt;b&lt;/font&gt;S chromosomes were Bantu type, 30% were Benin type, and 3% were Senegal type. The origin of the &lt;FONT FACE="Symbol"&gt;b&lt;/font&gt;S mutation in this population, estimated on the basis of &lt;FONT FACE="Symbol"&gt;b&lt;/font&gt;S-linked haplotypes, contradicts the historical records of direct slave trade from Africa to the northern region of Brazil. Historical records indicate a lower percentage of people from...
Tipo: Info:eu-repo/semantics/article
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000400001

Frequencies of CCR5-D32, CCR2-64I and SDF1-3’A mutations in Human Immunodeficiency Virus (HIV) seropositive subjects and seronegative individuals from the state of Pará in Brazilian Amazonia
Provedor de dados: 74
Autores: Carvalhaes,Fernanda Andreza de Pinho Lott; Cardoso,Greice Lemos; Vallinoto,Antonio Carlos Rosário; Machado,Luiz Fernando; Ishak,Marluisa de Oliveira Guimarães; Ishak,Ricardo; Guerreiro,João Farias.
The distribution of genetic polymorphisms of chemokine receptors CCR5-delta32, CCR2-64I and chemokine (SDF1-3’A) mutations were studied in 110 Human Immunodeficiency Virus type 1 (HIV-1) seropositive individuals (seropositive group) and 139 seronegative individuals (seronegative group) from the population of the northern Brazilian city of Belém which is the capital of the state of Pará in the Brazilian Amazon. The CCR5-delta32 mutation was found in the two groups at similar frequencies, i.e. 2.2% for the seronegative group and 2.7% for the seropositive group. The frequencies of the SDF1-3’A mutation were 21.0% for the seronegative group and 15.4% for the seropositive group, and the CCR2-64I allele was found at frequencies of 12.5% for the seronegative...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: CCR5; CCR2; SDF-1; HIV-1 infection; Allele frequency; Brazilian Amazon.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000500004

Inherited hemoglobin disorders in an Afro-Amazonian community: Saracura
Provedor de dados: 74
Autores: Cardoso,Greice Lemos; Takanashi,Silvania Yukiko Lins; Guerreiro,João Farias.
The most common hemoglobinopathies, viz, hemoglobins S and C, and α-and β-thalassemias, were investigated through the molecular screening of 116 subjects from the community of Saracura, comprising fugitive African slaves from farms of the municipality of Santarém, in the west of Pará State, Brazilian Amazon. The observed frequency of the HBB*S gene (0.9%) was significantly lower than that encountered in other Afro-derived communities in the region. Concomitantly, the absence of the HBB*C allele has been reported for most of the Afro-Amazonian communities thus far studied. As remnant populations of quilombos are generally small, the heterogeneous distribution of HBB*S and HBB*C alleles among them is probably due to genetic drift and/or founder effect. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sickle cell disease; Thalassemias; Afro-Amazonian.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000400002

CYP21 gene mutations in Brazilian patients with 21-hydroxylase deficiency from the Amazon region
Provedor de dados: 74
Autores: Carvalho,Tarcísio André Amorim de; Souza,Izabel Cristina Neves de; Yoshioka,France Keiko Nascimento; Caldato,Milena Coelho Fernandes; Torres,Nilza Nei; Garcia,Lena Stilianidi; Guerreiro,João Farias.
Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (P450c21, CYP21) accounts for about 95% of all CAH cases. The incidence of CYP21 gene mutations has been extensively studied in the last years, but in Brazil it has been investigated only in Southeast Brazilian patients. This study is the first report on the distribution of CYP21 mutations in patients from the Amazon region. Direct sequencing of the CYP21 gene identified at least one mutation in 96% of the studied chromosomes. The most common mutations found were IVS2-13A/C &gt; G (36%), Q318X (12%), V281L (12%), 1760_1761insT (9%), Cluster E6 (7%), and P30L (7%). The worldwide most common mutations were identified among patients from the Amazon region at frequencies that may be expected...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon region; 21-hydroxylase deficiency; DNA sequencing.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000400004

Genetic relationships among native americans based on beta-globin gene cluster haplotype frequencies
Provedor de dados: 74
Autores: Mousinho-Ribeiro,Rita de Cassia; Pante-de-Sousa,Gabriella; Santos,Eduardo José Melo dos; Guerreiro,João Farias.
The distribution of b-globin gene haplotypes was studied in 209 Amerindians from eight tribes of the Brazilian Amazon: Asurini from Xingú, Awá-Guajá, Parakanã, Urubú-Kaapór, Zoé, Kayapó (Xikrin from the Bacajá village), Katuena, and Tiriyó. Nine different haplotypes were found, two of which (n. 11 and 13) had not been previously identified in Brazilian indigenous populations. Haplotype 2 (+ - - - -) was the most common in all groups studied, with frequencies varying from 70% to 100%, followed by haplotype 6 (- + + - +), with frequencies between 7% and 18%. The frequency distribution of the b-globin gene haplotypes in the eighteen Brazilian Amerindian populations studied to date is characterized by a reduced number of haplotypes (average of 3.5) and low...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA polymorphisms; Brazilian Amerindians; Genetic diversity.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300002

Allele frequency distributions of six hypervariable loci (D1S80, APOB, D4S43, vW1, F13A and DYS19) in two African-Brazilian communities from the Amazon region
Provedor de dados: 74
Autores: Vallinoto,Izaura Maria Vieira Cayres; Vallinoto,Antonio Carlos Rosário; Valente,Cristina Maria Duarte; Guerreiro,João Farias.
The allele frequency distributions of three VNTR (D1S80, APOB and D4S43) and three STR (vW1, F13A1 and DYS19) loci were investigated in two Afro-Brazilian populations from the Amazon: Curiau and Pacoval. Exact tests for population differentiation revealed significant differences in allele frequency between populations only for the D1S80 and APOB loci. A statistically significant deviation from the Hardy-Weinberg equilibrium was observed only in the D1S80 locus of the Pacoval sample. A neighbor-joining tree was constructed based on DA genetic distances of allele frequencies in four Afro-Brazilian populations from the Amazon (Pacoval, Curiau, Trombetas, and Cametá), along with those from Congo, Cameroon, Brazilian Amerindians, and Europeans. This analysis...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA polymorphisms; Afro-Brazilians; Hypervariable loci.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300003