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1.
Front Microbiol ; 14: 1301374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125564

RESUMO

Introduction: The high recombinogenic potential of HIV-1 has resulted in the generation of countless unique recombinant forms (URFs) and around 120 reported circulating recombinant forms (CRFs). Here we identify through analyses of near full-length genomes (NFLG) a new HIV-1 CRF derived from subtypes B and F1. Methods: HIV-1 protease-reverse transcriptase (Pr-RT) sequences were obtained by RT-PCR amplification from plasma RNA. Near full-length genome sequences were obtained after amplification by RT-PCR in 5 overlapping fragments. Phylogenetic sequence analyses were performed via maximum likelihood. Mosaic structures were analyzed by bootscanning and phylogenetic analyses of genome segments. Temporal and geographical estimations of clade emergence were performed with a Bayesian coalescent method. Results: Through phylogenetic analyses of HIV-1 Pr-RT sequences obtained by us from samples collected in Spain and downloaded from databases, we identified a BF1 recombinant cluster segregating from previously reported CRFs comprising 52 viruses, most from Brazil (n = 26), Spain (n = 11), and Italy (n = 9). The analyses of NFLG genomes of 4 viruses of the cluster, 2 from Spain and 2 from Italy, allowed to identify a new CRF, designated CRF75_BF1, which exhibits a complex mosaic structure with 20 breakpoints. All 4 patients harboring CRF75_BF1 viruses studied by us had CD4+ T-cell lymphocyte counts below 220/mm3 less than one year after diagnosis, a proportion significantly higher (p = 0.0074) than the 29% found in other patients studied in Spain by us during the same period. The origin of the clade comprising CRF75_BF1 and related viruses was estimated around 1984 in Brazil, with subsequent introduction of CRF75_BF1 in Italy around 1992, and migration from Italy to Spain around 1999. Conclusion: A new HIV-1 CRF, designated CRF75_BF1, has been identified. CRF75_BF1 is the 6th CRF of South American origin initially identified in Western Europe, reflecting the increasing relationship of South American and European HIV-1 epidemics. The finding of low CD4+ T-cell lymphocyte counts early after diagnosis in patients harboring CRF75_BF1 viruses warrants further investigation on the virulence of this variant.

2.
Front Microbiol ; 13: 863084, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694315

RESUMO

Circulating recombinant forms (CRFs) are important components of the HIV-1 pandemic. Those derived from recombination between subtype B and subsubtype F1, with 18 reported, most of them of South American origin, are among the most diverse. In this study, we identified a HIV-1 BF1 recombinant cluster that is expanding in Spain, transmitted mainly via heterosexual contact, which, analyzed in near full-length genomes in four viruses, exhibited a coincident BF1 mosaic structure, with 12 breakpoints, that fully coincided with that of two viruses (10BR_MG003 and 10BR_MG005) from Brazil, previously classified as CRF72_BF1. The three remaining Brazilian viruses (10BR_MG002, 10BR_MG004, and 10BR_MG008) previously identified as CRF72_BF1 exhibited mosaic structures highly similar, but not identical, to that of the Spanish viruses and to 10BR_MG003 and 10BR_MG005, with discrepant subtypes in two short genome segments, located in pol and gp120env. Based on these results, we propose that the five viruses from Brazil previously identified as CRF72_BF1 actually belong to two closely related CRFs, one comprising 10BR_MG002, 10BR_MG004, and 10BR_MG008, which keep their CRF72_BF1 designation, and the other, designated CRF122_BF1, comprising 10BR_MG003, 10BR_MG005, and the viruses of the identified Spanish cluster. Three other BF1 recombinant genomes, two from Brazil and one from Italy, previously identified as unique recombinant forms, were classified as CRF72_BF1. CRF122_BF1, but not CRF72_BF1, was associated with protease L89M substitution, which was reported to contribute to antiretroviral drug resistance. Phylodynamic analyses estimate the emergence of CRF122_BF1 in Brazil around 1987. Given their close phylogenetic relationship and similar structures, the grouping of CRF72_BF1 and CRF122_BF1 in a CRF family is proposed.

3.
Sci Rep ; 11(1): 11442, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34075073

RESUMO

Circulating recombinant forms (CRFs) contribute substantially to the HIV-1 pandemic. Among 105 CRFs described in the literature, 16 are BF intersubtype recombinants, most of South American origin, of which CRF12_BF is the most widely spread. A BF recombinant cluster identified in Bolivia was suggested to represent a new CRF_BF. Here we find that it belongs to a larger cluster incorporating 39 viruses collected in 7 countries from 3 continents, 22 of them in Spain, most from Bolivian or Peruvian individuals, and 12 in South America (Bolivia, Argentina, and Peru). This BF cluster comprises three major subclusters, two associated with Bolivian and one with Peruvian individuals. Near full-length genome sequence analyses of nine viruses, collected in Spain, Bolivia, and Peru, revealed coincident BF mosaic structures, with 13 breakpoints, 6 and 7 of which coincided with CRF12_BF and CRF17_BF, respectively. In a phylogenetic tree, they grouped in a clade closely related to these CRFs, and more distantly to CRF38_BF and CRF44_BF, all circulating in South America. These results allowed to identify a new HIV-1 CRF, designated CRF89_BF. Through phylodynamic analyses, CRF89_BF emergence was estimated in Bolivia around 1986. CRF89_BF is the fifth CRF member of the HIV-1 recombinant family related to CRF12_BF.


Assuntos
Variação Genética , Genoma Viral , Infecções por HIV/genética , HIV-1/genética , Filogenia , Recombinação Genética , Adulto , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , América do Sul/epidemiologia
4.
Vet Microbiol ; 168(1): 225-8, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24247021

RESUMO

In Argentina, data on the presence of members of the genus Bartonella is scarce. To increase knowledge about these zoonotic pathogens in this country, the presence and variability of Bartonella spp. was investigated in cats and dogs from Buenos Aires. Bartonella spp. was detected in 17.8% of cats, while all dogs tested negative by PCR and Reverse Line Blot. B. henselae was the most frequent species, being detected in 11.9% (14/101), while B. clarridgeiae was found in only 5.9% (6/101) of the cats. Afterwards, B. henselae isolates and positive blood samples were characterized by Multiple Locus Sequence Typing (MLST) and Multiple Locus Variable Number Tandem Repeats Analysis (MLVA). As result, four different MLST sequence types (ST) and eight MLVA profiles were identified. ST 1 was the most frequent variant found in cats, followed by ST 8. Interestingly, some of the MLVA profiles that were detected in this study have been previously associated with human disease, and represents a potential risk of infection. Veterinarians and physicians should consider the presence of these emerging pathogens in their diagnostic routine.


Assuntos
Infecções por Bartonella/veterinária , Bartonella/classificação , Bartonella/genética , Doenças do Gato/microbiologia , Animais , Argentina , Infecções por Bartonella/microbiologia , Gatos , Cães , Repetições Minissatélites , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase/veterinária
5.
Medicina (B Aires) ; 68(2): 144-6, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18499964

RESUMO

We present the clinical case of a man of 68 years who was admitted for dizziness and sensation of loss of conscience. The clinical examination revealed a body temperature of 37.5 degrees C and a murmur of mitral regurgitation. The echocardiogram showed a severe mitral regurgitation and left cavitie's dilatation; transesophageal echocardiogram showed a vegetation in the anterior leaflet of the mitral valve. In blood cultures grew a Gram-negative bacteria identified as Bartonella spp. A PCR demonstrated that it was a Bartonella quintana. The patient was treated with gentamicin, doxiciclin and ceftriaxone with satisfactory evolution. The remaining mitral insufficiency awaits surgical treatment.


Assuntos
Bartonella quintana/isolamento & purificação , Infecções por Bartonellaceae , Endocardite Bacteriana/microbiologia , Idoso , Antibacterianos/uso terapêutico , Infecções por Bartonellaceae/tratamento farmacológico , Ceftriaxona/uso terapêutico , Endocardite Bacteriana/tratamento farmacológico , Gentamicinas/uso terapêutico , Humanos , Masculino , Insuficiência da Valva Mitral/microbiologia , Reação em Cadeia da Polimerase
6.
Medicina (B.Aires) ; 68(2): 144-146, mar.-abr. 2008. ilus
Artigo em Espanhol | LILACS | ID: lil-633529

RESUMO

Presentamos el caso de un hombre de 68 años que ingresó por mareos y sensación de pérdida de la conciencia. El examen clínico reveló una temperatura de 37.5 °C y un soplo de regurgitación mitral. El ecocardiograma mostró una insuficiencia mitral grave con dilatación de las cavidades izquierdas, y el ecocardiograma transesofágico una vegetación en la valva anterior de la mitral. Los hemocultivos demostraron una bacteria Gram-negativa que luego se identificó como Bartonella spp. La PCR demostró que se trataba de una Bartonella quintana. Se trató con gentamicina, doxiciclina y ceftriaxona, evolucionando satisfactoriamente. La insuficiencia mitral remanente espera el tratamiento quirúrgico.


We present the clinical case of a man of 68 years who was admitted for dizziness and sensation of loss of conscience. The clinical examination revealed a body temperature of 37.5 °C and a murmur of mitral regurgitation. The echocardiogram showed a severe mitral regurgitation and left cavitie's dilatation; transesophageal echocardiogram showed a vegetation in the anterior leaflet of the mitral valve. In blood cultures grew a Gram-negative bacteria identified as Bartonella spp. A PCR demonstrated that it was a Bartonella quintana. The patient was treated with gentamicin, doxiciclin and ceftriaxone with satisfactory evolution. The remaining mitral insufficiency awaits surgical treatment.


Assuntos
Idoso , Humanos , Masculino , Infecções por Bartonellaceae , Bartonella quintana/isolamento & purificação , Endocardite Bacteriana/microbiologia , Antibacterianos/uso terapêutico , Infecções por Bartonellaceae/tratamento farmacológico , Ceftriaxona/uso terapêutico , Endocardite Bacteriana/tratamento farmacológico , Gentamicinas/uso terapêutico , Insuficiência da Valva Mitral/microbiologia , Reação em Cadeia da Polimerase
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