Comparative performances of seven quantitative Reverse-Transcription Polymerase Chain Reaction assays (RT-qPCR) for detecting SARS-CoV-2 infection in samples from individuals suspected of COVID-19 in São Paulo, Brazil

Objective.To evaluate the emergence and dissemination of metallo-β-lactamase (MBL)–producing Acinetobacter species.Design.All carbapenem-resistant Acinetobacter strains (1 strain per patient) collected during the period 1993–2001 were evaluated.Setting.A Brazilian tertiary care teaching hospital (Hospital São Paulo, São Paulo).Methods.Seventy-three strains of carbapenem-resistant Acinetobacter species were recovered from the organism bank of the hospital. All isolates were tested for antimicrobial susceptibility by broth microdilution methods, and the production of MBL was initially assessed by phenotypic tests (MBL Etest strip and a disk approximation test). The MBL enzymes were identified by polymerase chain reaction using primers for blaIMP’, blaVIM’, and blaSPM’ followed by gene sequencing. Genetic similarity among the carbapenem-resistant strains was evaluated by automated ribotyping.Results.Only colistin and ampicillin-sulbactam showed reasonable in vitro activity against carbapenem-resistant isolates (97% and 74% of isolates susceptible, respectively). More than half of the isolates (55%) had a positive MBL phenotypic test result and a positive polymerase chain reaction result for blaIMP_1 The proportion of IMP-1–producing Acinetobacter isolates among carbapenem-resistant strains increased from 0% in the 1993-1997 period to 29% in 1998 and 100% in the 1999-2001 period. No carbapenem-resistant Acinetobacter isolates that harbored blaVIM or blaSPM were detected. Molecular typing results revealed 20 ribogroups among carbapenem-resistant isolates. During the study period of 1994-2001, we identified 2 major ribogroups, 52-1 (MBL-negative and MBL-positive strains) and 60-7 (MBL-positive strains), that had a coefficient of similarity of 0.85 or higher.Conclusions.Our results indicate that IMP-1–producing strains of Acinetobacter emerged in our institution in 1998. Since then, production of this MBL was detected not only in the major ribogroups of carbapenem-resistant Acinetobacter species but also among isolates that belonged to 17 distinct ribogroups, indicating that this important mechanism of antimicrobial resistance was disseminated among distinct clones.

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Molecular typing of HLA class II antigens in a São Paulo population

Genetics and Molecular Biology ◽

10.1590/s1415-47571998000300001 ◽

1998 ◽

Vol 21 (3) ◽

pp. 301-305 ◽

Cited By ~ 8

Author(s):

A.C. Goldberg ◽

J.M. Chiarella ◽

M.L.C. Marin ◽

C. Rosales ◽

D. Banic ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Normal Population ◽

Sao Paulo ◽

Normal Sample ◽

São Paulo ◽

Chain Reaction ◽

Essential Information ◽

Polymerase Chain ◽

Hla Dqa1 ◽

The City

In the present paper we show data obtained from a normal population with a racially mixed profile typical of the city of São Paulo, State of São Paulo. Data were generated with polymerase chain reaction using sequence specific primers (PCR-SSP) for HLA-DRB and polymerase chain reaction followed by hybridization with sequence specific oligonucleotide probes (PCR-SSO) for HLA-DQA1 and HLA-DQB1 loci. HLA-DRB, DQA1, DQB1 and haplotype frequencies as well as common linkage disequilibria were found. This population was also shown to be in genetic equilibrium according to the Hardy-Weinberg law. HLA-DR typing of a normal sample from the city of Porto Velho, State of Rondonia, highlighted the importance of different sets of HLA profiles found in other regions of the country. This database provides essential information for screening studies of disease associations, forensic analyses and transplants.

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