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1.
Clin Infect Dis ; 66(11): 1733-1741, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29211835

RESUMO

Background: In 2014-2015, 242 individuals aged 2-89 years were newly diagnosed with human immunodeficiency virus type 1 (HIV-1) in Roka, a rural commune in Cambodia. A case-control study attributed the outbreak to unsafe injections. We aimed to reconstruct the likely transmission history of the outbreak. Methods: We assessed in 209 (86.4%) HIV-infected cases the presence of hepatitis C virus (HCV) and hepatitis B virus (HBV). We identified recent infections using antibody (Ab) avidity testing for HIV and HCV. We performed amplification, sequencing, and evolutionary phylogenetic analyses of viral strains. Geographical coordinates and parenteral exposure through medical services provided by an unlicensed healthcare practitioner were obtained from 193 cases and 1499 controls during interviews. Results: Cases were coinfected with HCV (78.5%) and HBV (12.9%). We identified 79 (37.8%) recent (<130 days) HIV infections. Phylogeny of 202 HIV env C2V3 sequences showed a 198-sample CRF01_AE strains cluster, with time to most recent common ancestor (tMRCA) in September 2013 (95% highest posterior density, August 2012-July 2014), and a peak of 15 infections/day in September 2014. Three geospatial HIV hotspots were discernible in Roka and correlated with high exposure to the practitioner (P = .04). Fifty-nine of 153 (38.6%) tested cases showed recent (<180 days) HCV infections. Ninety HCV NS5B sequences formed 3 main clades, 1 containing 34 subtypes 1b with tMRCA in 2012, and 2 with 51 subtypes 6e and tMRCAs in 2002-2003. Conclusions: Unsafe injections in Cambodia most likely led to an explosive iatrogenic spreading of HIV, associated with a long-standing and more genetically diverse HCV propagation.


Assuntos
Surtos de Doenças , Infecções por HIV/epidemiologia , Infecções por HIV/etiologia , Injeções/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Camboja/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , HIV-1 , Humanos , Doença Iatrogênica/epidemiologia , Masculino , Pessoa de Meia-Idade , Filogenia , População Rural , Adulto Jovem
2.
Med Hypotheses ; 160: 110775, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35095175

RESUMO

In SARS-CoV-2, at the S1/S2 furin cleavage site, a four amino acid insert (P-R-R-A) not found in closely related corona viruses, has been shown to facilitate entry into respiratory epithelial cells and promote virus transmission, infectivity and virulence. By cupric aerosol treatment, complexation of these four amino acids (-P-R-R-A-), at the spike (S) protein site will lead to a conformational change possibly impeding SARS-CoV-2 replication process in the respiratory track. Since these four amino acids yield strong and stable copper complexes, subsequent to a steric hindrance, this complexation will disturb the furin-like protease cleavage at the spike protein site as it has been recently shown in vitro with copper gluconate. The compilation of stability constants for copper amino-acid complex formation, showing values of the same order of magnitude for all the twenty proteinogenic amino-acids demonstrate thermodynamically that copper amino-acid chelation for SARS-CoV-2 virus will not be affected by mutations leading to amino acid exchanges in the spike protein region. Given its low toxicity, and its very low stability formation constant, copper acetate is proposed rather than copper gluconate for possible cupric aerosol or nasal spray treatments aimed at impeding SARS-CoV-2 multiplication. It will open different medical perspectives, complementary to vaccination, in the fight against COVID 19 native virus, variants and future mutants.

3.
J Clin Microbiol ; 48(9): 3281-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20610669

RESUMO

There is no reliable and simple diagnostic marker available to diagnose recent hepatitis C virus (HCV) infection. It has been shown that the avidity of specific IgG antibody is low in primary viral infection and increases with time. We report the development of an anti-HCV avidity assay derived from a commercially available test. A panel of 117 sera was first examined for IgG avidity. It was composed of samples from patients with recent (group 1, n = 14), chronic (group 2, n = 70), and resolved (group 3, n = 33) HCV infections. Avidity index (AI) values observed in recently infected patients were significantly lower (12.0% +/- 9.2% [mean +/- standard deviation]) than those found in chronic carriers (83.1% +/- 15.2%). Using a threshold of 43.0%, this assay distinguished between groups 1 and 2 with very high sensitivity (98%) and specificity (100%). For group 3, a broader distribution of the AI values was observed (54.8% +/- 27.3%), suggesting that this index would not be useful in HCV RNA-negative patients. Blind validation of the test was carried out with a panel of 36 serum samples from 17 HCV seroconverters. The assay described here is a useful tool to distinguish recent from chronic infection in HCV-viremic patients.


Assuntos
Afinidade de Anticorpos , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , Hepatite C/imunologia , Imunoglobulina G/sangue , Virologia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
4.
J Trace Elem Med Biol ; 39: 50-53, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27908423

RESUMO

In Creutzfeldt Jakob, Alzheimer and Parkinson diseases, copper metalloproteins such as prion, amyloid protein precursor and α-synuclein are able to protect against free radicals by reduction from cupric Cu+2 to cupreous Cu+. In these pathologies, a regional copper (Cu) brain decrease correlated with an iron, zinc or manganese (Mn) increase has previously been observed, leading to local neuronal death and abnormal deposition of these metalloproteins in ß-sheet structures. In this study we demonstrate the protective effect of Cu metalloproteins against deleterious free-radical effects. With neuroblastoma SH-SY5Y cell cultures, we show that bovine brain prion protein in Cu but not Mn form prevents free radical-induced neuronal death. The survival ratio of SH-SY5Y cells has been measured after UV irradiation (free radical production), when the incubating medium is supplemented with bovine brain homogenate in native, Cu or Mn forms. This ratio, about 28% without any addition or with bovine brain protein added in Mn form, increases by as much as 54.73% with addition to the culture medium of native bovine brain protein and by as much as 95.95% if the addition is carried out in cupric form. This protective effect of brain copper protein against free radical-induced neuronal death has been confirmed with Inductively Coupled Plasma Mass Spectrometry Mn and Cu measurement in bovine brain homogenates: respectively lower than detection limit and 9.01µg/g dry weight for native form; lower than detection limit and 825.85µg/g dry weight for Cu-supplemented form and 1.75 and 68.1µg/g dry weight in Mn-supplemented brain homogenate.


Assuntos
Cobre/metabolismo , Neuroblastoma/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Proteínas Priônicas/química , Proteínas Priônicas/metabolismo , Animais , Bovinos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobre/farmacologia , Radicais Livres/antagonistas & inibidores , Radicais Livres/química , Radicais Livres/farmacologia , Humanos , Manganês/metabolismo , Manganês/farmacologia , Proteínas Priônicas/farmacologia , Células Tumorais Cultivadas
5.
Neurotoxicology ; 27(3): 437-44, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16481041

RESUMO

The exchange between copper and seven transition metals is studied in a bovine brain obex homogenate according to the redox status of the medium. In reductive conditions, almost all the studied metals can substitute for copper when it is in the reduced form Cu+. This substitution is reversible, since copper uptake as Cu++ is restored in an oxidizing medium but only Co++, Ni++ and Mn++, in this decreasing order, can substitute perfectly for copper in bovine brain homogenate. To study free radical effects on bovine brain proteins, at first a copper substitution was processed in order to inhibit superoxide dismutase-like protective properties against free radicals in copper metalloproteins. Manganese was selected since a brain copper decrease correlated with a manganese increase is well-known in transmissible spongiform encephalopathies. Results for bovine brain homogenate, initially negative in the Western blot Prionics test, indicate that the substitution of manganese for copper in a reducing medium and exposure to UVA-induced free radicals produce proteinase K resistant prion. These findings suggest that an impairment in brain metal homeostasis leading to oxidative abnormalities may be involved in transmissible spongiform encephalopathies.


Assuntos
Encéfalo/efeitos dos fármacos , Cobre/farmacologia , Radicais Livres/metabolismo , Manganês/farmacologia , Príons/química , Análise de Variância , Animais , Western Blotting , Encéfalo/metabolismo , Bovinos , Diálise/métodos , Substâncias Macromoleculares/química , Metais Pesados , Oxirredução/efeitos dos fármacos , Peptídeo Hidrolases/metabolismo , Raios Ultravioleta/efeitos adversos
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