Publications by authors named "Angela M Barreto"

The identification of recent HIV infection is important for epidemiological studies and to monitor the epidemic. The objective of this study was to evaluate two rapid tests that are easily available to the Brazilian scientific community for using as markers of recent HIV infection. The Rapid Test - HIV-1/2 Bio-Manguinhos (Bio-Manguinhos/Fiocruz, Brazil) and the Rapid Check HIV 1&2 (NDI-UFES, Center for Infectious Diseases, Universidade Federal do Espírito Santo) were tested, using 489 samples with HIV positive serology, from blood donors, previously classified as recent or long-term infection by serological testing algorithm for recent HIV seroconversion (STARHS) or LS-HIV Vitros assay methods.

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Background: In Brazil it is mandatory to screen donors for human immunodeficiency virus (HIV) antibodies using two immunoassays (IAs) in parallel. Confirmatory testing is performed only on reactive donors who return for counseling. The goal of this analysis was to determine if concordant IA reactivity accurately predicts infection and can be used for HIV incidence and/or prevalence analyses.

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Background: A major problem in Chagas disease donor screening is the high frequency of samples with inconclusive results. The objective of this study was to describe patterns of serologic results among donors to the three Brazilian REDS-II blood centers and correlate with epidemiologic characteristics.

Study Design And Methods: The centers screened donor samples with one Trypanosoma cruzi lysate enzyme immunoassay (EIA).

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Objective: To analyze and compare the mutations in two different regions of the katG gene, which is responsible for isoniazid (INH) resistance.

Methods: We analyzed 97 multidrug-resistant Mycobacterium tuberculosis strains isolated in cultures of sputum samples obtained from the Professor Hélio Fraga Referral Center, in Brasília, Brazil. Another 6 INH-sensitive strains did not present mutations and were included as controls.

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Objective: To analyze the clinical characteristics and evolution of a group of patients with positive sputum cultures for multidrug-resistant (MDR) Mycobacterium tuberculosis and treated at a referral center in the city of Rio de Janeiro, Brazil.

Methods: Based on the positive results in sputum cultures for MDR M. tuberculosis, 50 patients were selected, and their clinical data were obtained from the Brazilian Ministry of Health MDR-TB Database.

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Tubercle bacilli may survive in unstained heat-fixed sputum smears and may be an infection risk to laboratory staff. We compared the effectiveness of 1% and 5% sodium hypochlorite, 5% phenol, 2% glutaraldehyde, and 3.7% formalin in killing Mycobacterium tuberculosis present in smears prepared from 51 sputum samples.

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In order to evaluate the Organon Teknika MB/BacT system used for testing indirect susceptibility to the alternative drugs ofloxacin (OFLO), amikacin (AMI), and rifabutin (RIF), and to the usual drugs of standard treatment regimes such as rifampin (RMP), isoniazid (INH), pyrazinamide (PZA), streptomycin (SM), ethambutol (EMB), and ethionamide (ETH), cultures of clinical specimens from 117 patients with pulmonary tuberculosis under multidrug-resistant investigation, admitted sequentially for examination from 2001 to 2002, were studied. Fifty of the Mycobacterium tuberculosis cultures were inoculated into the gold-standard BACTEC 460 TB (Becton Dickinson) for studying resistance to AMI, RIF, and OFLO, and the remaining 67 were inoculated into Lowenstein Jensen (LJ) medium (the gold standard currently used in Brazil) for studying resistance to RMP, INH, PZA, SM, EMB, and ETH. We observed 100% sensitivity for AMI (80.

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Objective: In 1998, the Brazilian Ministry of Health made it mandatory for all blood banks in the country to screen donated blood for human immunodeficiency virus (HIV) concomitantly using two different enzyme immunoassay (EIA) tests. Concerned with the best use of available resources, our objective with this study was to evaluate the usefulness of conducting two EIA screening tests instead of just one.

Methods: We analyzed data from 1999 through 2001 obtained by testing 698 191 units of donated blood using two EIA HIV screening tests concomitantly at the Pro-Blood Foundation/Blood Center of São Paulo (Fundação Pró-Sangue/Hemocentro de São Paulo), which is a major blood center in the city of São Paulo, Brazil.

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Objectives: To analyze the changes in the proportion of blood units discarded from 1991 through 2001 at the Pro-Blood Foundation/Blood Center of São Paulo (Fundação Pró-Sangue/Hemocentro de São Paulo), which is the largest blood bank in Latin America, and to determine the prevalence of infectious diseases among donors at the Blood Center in November 2001.

Methods: We compiled data concerning the discarding of blood units due to the presence of serological markers for communicable diseases at the Blood Center during the period from 1991 through 2001. To determine the prevalence of infectious diseases, 9 942 screened samples were analyzed in November 2001; all reactive samples underwent confirmatory tests.

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In order to evaluate the direct-method test of sensitivity to drugs used in the principal tuberculosis treatment regimes, in the Organon Teknika MB/BacT system, we tested 50 sputum samples positive to microscopy taken from patients with pulmonary tuberculosis and with clinical indications for an antibiogram, admitted sequentially for examination during the routine of the reference laboratory. The material was treated v/v with 23% trisodium phosphate solution, incubated for 24 h at 35 degrees C, and neutralized v/v with 20% monosodium phosphate solution. The material was then centrifuged and the sediment inoculated into flasks containing Rifampin - 2 micro g/ml, Isoniazid - 0.

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