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Registros recuperados: 21 | |
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Bahia,Fabianna; Pedroso,Célia; Netto,Eduardo Martins; Figueiredo,Ricardo; Pinto Neto,Lauro; Brites,Carlos. |
We analyzed the first 96 patients tested for HIV resistance to antiretroviral therapy in three Brazilian states. The HIV-1 reverse transcriptase (RT) and protease (PR) were sequenced by using the ABI ViroSeq system. The drugs previously used for each patient were recorded and correlated with the mutations found in the samples. Viral load (VL) and CD4 count were also recorded. Only one patient had the wild type sequence. The most prevalent mutations were: 184V (59%), 41L (47.9%), 63P (53%), 215Y (50%), 36I (46%), 10I (35%), 67N (42%), 77I (37%), 90M (36%) and 210W (33%). A positive correlation between the number of previously used ARVs and the number of mutations was observed (p<0.05). Associations between mutations and ARV drugs were identified at... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: HIV-1; Mutations; Resistance; Antiretrovirals. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702004000400003 |
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Prasad,Polu Giri; Jasmine,Mohammad Shaik; kanta,Kota Neela Mani; Deepthi,Karumanchi; Allam,Uday Sankar. |
ABSTRACT Purpose and objectives Detection of drug resistance plays a crucial role in tuberculosis (TB) treatment and prevention of Mycobacterium tuberculosis (MTB) transmission. The aim of this study was to determine the levels and patterns of resistance of MTB isolates to two key anti-TB drugs (rifampicin, RIF and isoniazid, INH) and the type of mutations in drug resistance genes (rpoB, katG and inhA) of the isolates at the southern coastal region of Andhra Pradesh, India, using commercially available GenoType MTBDRplus assay under the Revised National TB Control Program. Methods GenoType MTBDRplus assay was performed on 2859 sputum smear-positive samples and the mutations in the genes responsible for resistance (rpoB, katG and inhA) were analyzed.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Multidrug resistance; Mycobacterium tuberculosis; MTBDRplus assay; Mutations; Molecular detection. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702019000500281 |
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Tan,You-Wen; Ge,Guo-Hong; Zhao,Wei; Gan,Jian-He; Zhao,Yun; Niu,Zhi-Lin; Zhang,Dong-Jun; Chen,Li; Yu,Xue- Jun; Yang,Li-Jun. |
OBJECTIVE: This study aimed to determine the natural prevalence of variants of tyrosine-methionine-aspartic acid-aspartic acid (YMDD) motif in patients with chronic hepatitis B (CHB), and to explore its relation with demographic and clinical features, hepatitis B virus (HBV) genotypes, and HBV DNA levels. METHODS: A total of 1,042 antiviral treatment naïve CHB patients (including with lamivudine [LAM]) in the past year were recruited from outpatient and inpatient departments of six centers from December 2008 to June 2010. YMDD variants were analyzed using the HBV drug resistance line probe assay (Inno-Lipa HBV-DR). HBV genotypes were detected with polymerase chain reaction (PCR) microcosmic nucleic acid cross-ELISA, and HBV deoxyribonucleic acid (DNA) was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: YMDD; Mutations; Chronic hepatitis B; Anti-viral therapy. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702012000300006 |
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Brites,Carlos; Pinto-Neto,Lauro; Medeiros,Melissa; Nunes,Estevão; Sprinz,Eduardo; Carvalho,Mariana. |
Abstract Background Development of drug-resistance mutations is the main cause of failure in antiretroviral therapy. In Brazil, there is scarce information on resistance pattern for patients failing antiretroviral therapy. Objectives To define the HIV mutational profile associated with drug resistance in Brazilian patients from 5 large cities, after first, second or further failures to antiretroviral therapy. Methods We reviewed genotyping results of 1520 patients failing therapy in five Brazilian cities. Frequency of mutations, mean number of active drugs, viral susceptibility to each antiretrovirals drug, and regional differences were assessed. Results Mean time of antiretrovirals use was 22.7 ± 41.1 months. Mean pre-genotyping viral load was 4.2 ±... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: HIV; Resistance; Brazil; Mutations. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702016000400323 |
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Victoria,Flamir da Silva; Oliveira,Cintia Mara Costa de; Victoria,Marilu Barbieri; Victoria,Cristian Barbieri; Ferreira,Luis Carlos Lima. |
The present study was conducted with 55 patients native from western Brazilian Amazonia, who were HBV-DNA positive after seroconversion of HBeAg. It is a descriptive case study, with the patients separated into two groups: with hepatitis and without hepatitis on histological examination. The aim of the present study was to describe the clinical and molecular characteristics of patients who are chronic carriers of HBsAg. The prevalence of hepatitis was 63.64%, with a predominance of males (41.82%) and a mean age of 42.5 years, occurring mostly in natives of the southeast sub-region (32.73%). Time was a variable proportional to the course of the disease and the most frequent symptoms were: dyspepsia, asthenia and loss of libido with the majority of the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: HBeAg-negative chronic hepatitis B; Western Brazilian Amazonia; Mutations. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702008000100008 |
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C. Neto,E.; Schulte,J.; Rubim,R.; Lewis,E.; DeMari,J.; Castilhos,C.; Brites,A.; Giugliani,R.; Jensen,K.P.; Wolf,B.. |
Biotinidase deficiency is an inherited metabolic disorder characterized by neurological and cutaneous symptoms. Fortunately, it can be treated and the symptoms prevented by oral administration of the vitamin biotin. Using dried blood-soaked filter paper cards, biotinidase activity was determined in the sera of 225,136 newborns in Brazil. Mutation analysis performed on DNA from 21 babies with low serum biotinidase activity confirmed that 3 had profound biotinidase deficiency (less than 10% of mean normal sera biotinidase activity), 10 had partial biotinidase deficiency (10 to 30% of mean normal serum activity), 1 was homozygous for partial biotinidase deficiency, 4 were heterozygous for either profound or partial deficiency, and 3 were normal. Variability... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Newborn screening; Biotinidase deficiency; Biotinidase; Mutations; Enzyme assay. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000300001 |
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Perone,C.; Medeiros,G.S.; del Castillo,D.M.; de Aguiar,M.J.B.; Januário,J.N.. |
The nature and frequency of cystic fibrosis mutations in Brazil is not uniform due to the highly varied ethnic composition of the population. The average frequency of the F508del mutation has been reported to be 48.6%. Other common mutations in Brazil are G542X, R1162X, and N1303K. The aim of this study was to analyze the frequency of 8 mutations (F508del, G542X, R1162X, N1303K, W1282X, G85E, 3120+1G>A, and 711+1G>T) in a sample of 111 newborn patients with cystic fibrosis diagnosed by the Cystic Fibrosis Neonatal Screening Program of Minas Gerais State. The mutations were tested by allele-specific oligonucleotide PCR with specially designed primers. An allele frequency of 48.2% was observed for the F508del mutation, and allele frequencies of 5.41,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: CFTR gene; Cystic fibrosis; Mutations; Neonatal screening; F508del. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010000200003 |
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Morales,M.M.; Capella,M.A.M.; Lopes,A.G.. |
Cystic fibrosis (CF) is a lethal autosomal recessive genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR). Mutations in the CFTR gene may result in a defective processing of its protein and alter the function and regulation of this channel. Mutations are associated with different symptoms, including pancreatic insufficiency, bile duct obstruction, infertility in males, high sweat Cl-, intestinal obstruction, nasal polyp formation, chronic sinusitis, mucus dehydration, and chronic Pseudomonas aeruginosa and Staphylococcus aureus lung infection, responsible for 90% of the mortality of CF patients. The gene responsible for the cellular defect in CF was cloned in 1989 and its protein product CFTR is activated by an increase... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: CFTR; Cystic fibrosis; Chloride channel; Function; Structure; Mutations. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000800013 |
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Esteves,V.F.; Thuler,L.C.S.; Amêndola,L.C.; Koifman,R.J.; Koifman,S.; Frankel,P.P.; Vieira,R.J.S.. |
Of all malignant neoplasias affecting women, breast cancer has the highest incidence rate in Brazil. The objective of the present study was to determine the frequency of genetic modifications in families with medium and high risk for breast and ovarian cancer from different regions of Brazil. An exploratory, descriptive study was carried out on the prevalence of the BRCA1 and BRCA2 mutations in case series of high-risk families for breast and/or ovarian cancer. After heredogram construction, a blood sample was taken and DNA extraction was performed in all index cases. The protein truncation test was used to screen for truncated mutations in exon 11 of the BRCA1 gene and in exons 10 and 11 of the BRCA2 gene. Of the 612 individuals submitted to genetic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Breast cancer; BRCA1; BRCA2; Mutations; Brazil. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000500009 |
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Paiva,J.B.; Penha Filho,R.A.C.; Pereira,E.A.; Lemos,M.V.F.; Barrow,P.A.; Lovell,M.A.; Berchieri Jr,A.. |
Salmonella enterica serovar Gallinarum (SG) is an intracellular pathogen of chickens. To survive, to invade and to multiply in the intestinal tract and intracellularly it depends on its ability to produce energy in anaerobic conditions. The fumarate reductase (frdABCD), dimethyl sulfoxide (DMSO)-trimethylamine N-oxide (TMAO) reductase (dmsABC), and nitrate reductase (narGHIJ) operons in Salmonella Typhimurium (STM) encode enzymes involved in anaerobic respiration to the electron acceptors fumarate, DMSO, TMAO, and nitrate, respectively. They are regulated in response to nitrate and oxygen availability and changes in cell growth rate. In this study mortality rates of chickens challenged with mutants of Salmonella Gallinarum, which were defective in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Salmonella Gallinarum; Anaerobic genes; Poultry; Mutations. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822009000400035 |
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Flores,Mariana Martins; Mazaro,Renata Dalcol; Langohr,Ingeborg Maria; Roy,Alma; Strother,Keith; Fighera,Rafael Almeida. |
ABSTRACT: The use of histologic classification by a 2-tier grading system only, immunohistochemistry (IHC) for KIT and Ki-67 and polymerase chain reaction (PCR) for internal tandem duplications (ITD) on exon 11 has improved the prognostication of canine cutaneous mast cell tumors (CCMTs) particularly in the United States. However, these techniques are not commonly used in most Brazilian laboratories. Likewise, no studies, to date, have investigated the occurrence of ITD in CCMTs from the country. Thus, this study tested the 2-tier grading system, the immunohistochemistry for KIT and Ki-67 and the PCR for exon 11 in a group of Brazilian CCMTs with the goal of investigating the applicability of these tests in a Brazilian laboratory. Of the 39 CCMTs, 69.2%... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Immunohistochemistry; Ki-67; Mutations; PCR; Mast cell tumor.. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016001001804 |
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Lima,Caroline Rocha de Oliveira; Rabelo,Rogério Elias; Vulcani,Valcinir Aloísio Scalla; Cardoso,Lorena Damasio; Sousa,Nicaelle Luan de Moura; Moura,Veridiana Maria Brianezi Dignani de. |
The p53 gene encodes a protein that has molecular weight of 53kD and is also called p53 protein, being constantly studied for its classic concept of "genome guardian". This gene plays a range of essential functions to ensure the cell cycle control, in addition to playing a central role in carcinogenesis. With respect to neoplasias, it prevents the neoplastic transformation through three intricate mechanisms. Depending on the extent of the mutation, different responses may be sent by p53 and those range since the disruption of the cell cycle, the correction of the mutation through the activation of repair proteins or still, the induction of senescence or cell death by apoptosis. This review aims to address the structural and functional aspects of the p53... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mutations; Neoplasia; Gene therapy; P53. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782012000500014 |
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Trovó,Alessandra B.; Goloni-Bertollo,Eny M.; Mancini,Ulises M.; Rahal,Paula; Azevedo Jr.,Walter F. de; Tajara,Eloiza H.. |
Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder caused by mutations in the NF1 gene. In the present study, a total of 55 unrelated NF1 patients were screened for mutations in the GAP-related domain/GRD (exons 20-27a) by single-strand conformation polymorphism (SSCP). Four different mutations were identified and, taken together, they comprise one nonsense substitution (Q1189X), one deletion (3525-3526delAA), one missense substitution (E1356G) and one mutation in the splice acceptor site (c.4111-1G>A). One novel polymorphism (c.4514+11C>G) and other three putative polymorphisms were also found (c.3315-27G>A, V1146I and V1317A). Genotype-phenotype correlations were investigated, but no particular association was detected. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gene NF1; GRD; Neurofibromatosis type 1; Mutations; Polymorphisms. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000300003 |
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Silveira,Zama Messala Luna da; Barbosa,Maria das Vitórias; Fernandes,Thales Allyrio Araújo de Medeiros; Kimura,Elza Miyuki; Costa,Fernando Ferreira; Sonati,Maria de Fátima; Rebecchi,Ivanise Marina Moretti; Medeiros,Tereza Maria Dantas de. |
35 unrelated individuals were studied for characterization as either heterozygous or homozygous for beta-thalassemia. Molecular analysis was done by PCR/RFLP to detect the mutations most commonly associated with beta-thalassemia (β0IVS-I-1, β+IVS-I-6, and β039). In the patients who showed none of these mutations, the beta-globin genes were sequenced. Of the 31 heterozygous patients, 13 (41.9%) had the β+IVS-I-6 mutation, 15 (48.4%) the β0IVS-I-1 mutation, 2 (6.5%) the β+IVS-I-110 mutation and 1 (3.2%) the β+IVS-I-5 mutation. IVS-I-6 was detected in the four homozygotes. The mutation in codon 39, often found in previous studies in Brazil, was not detected in the present case. This is the first study aiming at identifying mutations that determine... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hereditary hemoglobinopathies; Beta-thalassemia; Mutations; PCR-RFLP; Brazilian population. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000300010 |
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Viana,Gustavo M.; Lima,Nathália O. de; Cavaleiro,Rosely; Alves,Erik; Souza,Isabel C.N.; Feio,Raimunda; Leistner-Segal,Sandra; Schwartz,Ida; Giugliani,Roberto; Silva,Luiz C. Santana da. |
Mucopolysaccharidoses (MPS) are rare lysosomal disorders caused by the deficiency of specific lysosomal enzymes responsible for glycosaminoglycan (GAG) degradation. Enzyme Replacement Therapy (ERT) has been shown to reduce accumulation and urinary excretion of GAG, and to improve some of the patients' clinical signs. We studied biochemical and molecular characteristics of nine MPS patients (two MPS I, four MPS II and three MPS VI) undergoing ERT in northern Brazil. The responsiveness of ERT was evaluated through urinary GAG excretion measurements. Patients were screened for eight common MPS mutations, using PCR, restriction enzyme tests and direct sequencing. Two MPS I patients had the previously reported mutation p.P533R. In the MPS II patients, mutation... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mucopolysaccharidosis; Enzyme replacement therapy; Mutations; Glycosaminoglycans. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000300007 |
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Masood,Nosheen; Kayani,Mahmood Akhtar. |
CYP1A1 is the phase I enzyme that detoxifies the carcinogen or converts it into a more electrophilic form, metabolized by phase II enzymes like GSTP1. These detoxifying genes have been extensively studied in association with head and neck cancer (HNC) in different ethnic groups worldwide. The current study was aimed at screening genetic polymorphisms of genes CYP1A1 and GSTP1 in 388 Pakistani HNC patients and 150 cancer-free healthy controls, using PCR-SSCP. No already known variants of either gene were found, however a novel frameshift mutation due to insertion of T (g.2842_2843insT) was observed in the CYP1A1 gene. A statistically significant number (5.4%) of HNC cases, with the mean age of 51.75 (±15.7) years, presented this frameshift mutation in the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: GSTP1; CYP1A1; Head and neck cancer; Polymorphisms; Mutations. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000400001 |
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Oliveira,Raimundo Antonio G.; Oshiro,Marilena; Hirata,Mario H.; Hirata,Rosario D.C.; Ribeiro,Georgina S.; Medeiros,Tereza M.D.; Barretto,Orlando C. de O.. |
In this study, we used red cell glucose-6-phosphate dehydrogenase (G6PD) activity to screen for G6PD-deficient individuals in 373 unrelated asymptomatic adult men who were working with insecticides (organophosphorus and carbamate) in dengue prevention programs in 27 cities in São Paulo State, Brazil. Twenty-one unrelated male children suspected of having erythroenzymopathy who were attended at hospitals in São Paulo city were also studied. Fifteen of the 373 adults and 12 of the 21 children were G6PD deficient. G6PD gene mutations were investigated in these G6PD-deficient individuals by using PCR-RFLP, PCR-SSCP analysis and DNA sequencing. Twelve G6PD A-202A/376G and two G6PD Seattle844C, as well as a new variant identified as G6PD São Paulo, were detected... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glucose-6-phosphate dehydrogenase; Mutations; Polymorphism; Variants. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200007 |
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Registros recuperados: 21 | |
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