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1.
NPJ Vaccines ; 8(1): 149, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794010

RESUMO

COVID-19 vaccines were originally designed based on the ancestral Spike protein, but immune escape of emergent Variants of Concern (VOC) jeopardized their efficacy, warranting variant-proof vaccines. Here, we used preclinical rodent models to establish the cross-protective and cross-neutralizing capacity of adenoviral-vectored vaccines expressing VOC-matched Spike. CoroVaxG.3-D.FR, matched to Delta Plus Spike, displayed the highest levels of nAb to the matched VOC and mismatched variants. Cross-protection against viral infection in aged K18-hACE2 mice showed dramatic differences among the different vaccines. While Delta-targeted vaccines fully protected mice from a challenge with Gamma, a Gamma-based vaccine offered only partial protection to Delta challenge. Administration of CorovaxG.3-D.FR in a prime/boost regimen showed that a booster was able to increase the neutralizing capacity of the sera against all variants and fully protect aged K18-hACE2 mice against Omicron BA.1, as a BA.1-targeted vaccine did. The neutralizing capacity of the sera diminished in all cases against Omicron BA.2 and BA.5. Altogether, the data demonstrate that a booster with a vaccine based on an antigenically distant variant, such as Delta or BA.1, has the potential to protect from a wider range of SARS-CoV-2 lineages, although careful surveillance of breakthrough infections will help to evaluate combination vaccines targeting antigenically divergent variants yet to emerge.

2.
Lancet Reg Health Am ; 6: 100123, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34841388

RESUMO

BACKGROUND: Gam-COVID-Vac (SPUTNIK V) has been granted emergency use authorization in 70 nations and has been administered to millions worldwide. However, there are very few peer-reviewed studies describing its effects. Independent reports regarding safety and effectiveness could accelerate the final approval by the WHO. We aimed to study the long-term humoral immune response in naïve and previously infected volunteers who received SPUTNIK V. METHODS: Humoral immune responses, assayed by anti-SARS-CoV-2-spike-RBD IgG ELISA and neutralization assays, were measured in 602 healthcare workers at 0, 14, 28, 60 and 180 days after receiving SPUTNIK V between December 2020 and July 2021 in Tucumán, Argentina. FINDINGS: Seroconversion was detected in 97% of individuals after 28 days post-vaccination (dpv) (N = 405). Anti-RBD titers began to decrease after 60 dpv (N = 328), but remained detectable in 94% at 90 dpv (N = 224). At 180 dpv, anti-RDB titers persisted in 31% (N = 146). Previous infection triggered an increased immune response to the first dose and increased neutralization activity against variants of concern (VOC). Second doses in previously infected individuals further increased titers, even 90 dpv (N = 75). Basal antibody titers had more influence on post-vaccination anti-RBD responses than the time elapsed between diagnosis and vaccination (N = 274). INTERPRETATION: Data presented herein provides essential knowledge regarding the kinetics of antibodies induced by SPUTNIK V up to six months after immunization, and suggests that when considering one-dose vaccination policies for individuals with previous SARS-CoV-2 infection, serological studies to determine basal titers may be important, independent of when diagnosis occurred. FUNDING: Tucumán Public Health System (SIPROSA), Argentinean National Research Council (CONICET), National University of Tucumán (UNT).

3.
Sci Rep ; 11(1): 6044, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723318

RESUMO

Breast cancer is the leading cause of cancer death among women worldwide. Blocking a single signaling pathway is often an ineffective therapy, especially in the case of aggressive or drug-resistant tumors. Since we have previously described the mechanism involved in the crosstalk between Retinoic Acid system and protein kinase C (PKC) pathway, the rationale of our study was to evaluate the effect of combining all-trans-retinoic acid (ATRA) with a classical PCK inhibitor (Gö6976) in preclinical settings. Employing hormone-independent mammary cancer models, Gö6976 and ATRA combined treatment induced a synergistic reduction in proliferative potential that correlated with an increased apoptosis and RARs modulation towards an anti-oncogenic profile. Combined treatment also impairs growth, self-renewal and clonogenicity potential of cancer stem cells and reduced tumor growth, metastatic spread and cancer stem cells frequency in vivo. An in-silico analysis of "Kaplan-Meier plotter" database indicated that low PKCα together with high RARα mRNA expression is a favorable prognosis factor for hormone-independent breast cancer patients. Here we demonstrate that a classical PKC inhibitor potentiates ATRA antitumor effects also targeting cancer stem cells growth, self-renewal and frequency.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Mamárias Experimentais , Proteínas de Neoplasias , Células-Tronco Neoplásicas/enzimologia , Proteína Quinase C beta , Proteína Quinase C-alfa , Animais , Linhagem Celular Tumoral , Feminino , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Proteína Quinase C beta/antagonistas & inibidores , Proteína Quinase C beta/metabolismo , Proteína Quinase C-alfa/antagonistas & inibidores , Proteína Quinase C-alfa/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Tretinoína/farmacologia
4.
N Engl J Med ; 383(23): 2230-2241, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33264545

RESUMO

BACKGROUND: From November 2018 through February 2019, person-to-person transmission of Andes virus (ANDV) hantavirus pulmonary syndrome occurred in Chubut Province, Argentina, and resulted in 34 confirmed infections and 11 deaths. Understanding the genomic, epidemiologic, and clinical characteristics of person-to-person transmission of ANDV is crucial to designing effective interventions. METHODS: Clinical and epidemiologic information was obtained by means of patient report and from public health centers. Serologic testing, contact-tracing, and next-generation sequencing were used to identify ANDV infection as the cause of this outbreak of hantavirus pulmonary syndrome and to reconstruct person-to-person transmission events. RESULTS: After a single introduction of ANDV from a rodent reservoir into the human population, transmission was driven by 3 symptomatic persons who attended crowded social events. After 18 cases were confirmed, public health officials enforced isolation of persons with confirmed cases and self-quarantine of possible contacts; these measures most likely curtailed further spread. The median reproductive number (the number of secondary cases caused by an infected person during the infectious period) was 2.12 before the control measures were enforced and decreased to 0.96 after the measures were implemented. Full genome sequencing of the ANDV strain involved in this outbreak was performed with specimens from 27 patients and showed that the strain that was present (Epuyén/18-19) was similar to the causative strain (Epilink/96) in the first known person-to-person transmission of hantavirus pulmonary syndrome caused by ANDV, which occurred in El Bolsón, Argentina, in 1996. Clinical investigations involving patients with ANDV hantavirus pulmonary syndrome in this outbreak revealed that patients with a high viral load and liver injury were more likely than other patients to spread infection. Disease severity, genomic diversity, age, and time spent in the hospital had no clear association with secondary transmission. CONCLUSIONS: Among patients with ANDV hantavirus pulmonary syndrome, high viral titers in combination with attendance at massive social gatherings or extensive contact among persons were associated with a higher likelihood of transmission. (Funded by the Ministerio de Salud y Desarrollo Social de la Nación Argentina and others.).


Assuntos
Surtos de Doenças , Síndrome Pulmonar por Hantavirus/transmissão , Orthohantavírus , Adolescente , Adulto , Animais , Argentina/epidemiologia , Análise Química do Sangue , Portador Sadio , Feminino , Orthohantavírus/genética , Síndrome Pulmonar por Hantavirus/epidemiologia , Síndrome Pulmonar por Hantavirus/mortalidade , Síndrome Pulmonar por Hantavirus/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Roedores , Carga Viral , Adulto Jovem
5.
Vector Borne Zoonotic Dis ; 5(1): 11-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15815145

RESUMO

Following the occurrence of the first laboratory-confirmed cases of hantavirus pulmonary syndrome (HPS) in Maranhao State, Brazil, rodents were trapped and rodent materials screened by ELISA for antibodies to Sin Nombre and Andes hantaviruses. Antibody-positive samples were tested by RT-PCR, amplified products were sequenced, and phylogenetic trees were constructed for comparison with known hantaviruses. From 104 rodent blood samples collected (40 Bolomys lasiurus, 52 Holochilus sciureus, 12 Oligoryzomys fornesi, and one Proechimys guyannensis), 21 (20.2%) were antibody-positive (one B. lasiurus, five O. fornesi, and 15 H. sciureus). Hantavirus RNA was amplified by PCR from two O. fornesi and four H. sciureus. Viral sequencing identified two hantavirus genotypes. The genotype recovered from O. fornesi, is designated herein as Anajatuba (ANAJ) and the genotype recovered from H. sciureus is designated Rio Mearim (RIME). Phylogenetic analysis of a 643-nucleotide region of the N segment showed both viruses to be most closely related (94-96% nucleotide homology) to Río Mamoré virus, a virus associated with Oligoryzomys microtis in Bolivia and Peru, but not found in northern Brazil. O. fornesi was frequently captured in and around human dwellings. H. sciureus, is a semi-aquatic rodent captured only in remote areas rarely frequented by humans.


Assuntos
Síndrome Pulmonar por Hantavirus/virologia , Orthohantavírus/genética , Roedores/virologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Sequência de Bases , Brasil , DNA Viral/química , DNA Viral/genética , Reservatórios de Doenças/veterinária , Ensaio de Imunoadsorção Enzimática , Genótipo , Orthohantavírus/classificação , Orthohantavírus/imunologia , Orthohantavírus/isolamento & purificação , Síndrome Pulmonar por Hantavirus/transmissão , Humanos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Zoonoses
6.
Mem Inst Oswaldo Cruz ; 98(6): 727-32, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14595446

RESUMO

We studied hantavirus seroprevalence and virus variability in rodent populations in Diego Gaynor, northwest of Buenos Aires province, Argentina. Rodent samplings were conducted in railroads and cropfield borders in March and July 1999, September and December 2000, and March 2001. Antibody detection was performed by an enzyme link immunosorbent assay (ELISA), using the recombinant nucleoprotein of Andes (AND) virus as antigen. Tissue samples were taken from positive antibody individuals in order to confirm the presence of hantavirus genomic material and to identify virus genotypes. Akodon azarae was the most abundant species, followed by Oligoryzomys flavescens, while Calomys laucha and C. musculinus were rarely caught. We found a rate of seroprevalence of 9.3% for a total sample of 291 A. azarae and 13.5% for 37 O. flavescens. After molecular analyses of hantavirus, we confirmed the presence of hantavirus genomic material in 16 individuals with ELISA (+) results and two individuals with ELISA (-). Four amplimers for each species were sequenced and compared to the corresponding sequences of representative hantaviruses. We identified the AND Cent Lec from three O. flavescens, and the Pergamino virus from four A. azarae and from one O. flavescens. A. azarae males had higher seroprevalence than females, and heavier individuals showed higher seroprevalence than lighter ones. We did not find seroprevalence differences according to sex in O. flavescens, although this result may have been produced by the low sample size. The lowest seroprevalence was found in a period of high rodent density, when juveniles prevailed in the population. We found higher seroprevalences than those detected in previous studies for other localities of central Argentina where cases of hantavirus pulmonary syndrome (HPS) have been reported. The presence of AND Cent Lec virus in rodent populations of the study area, which is responsible of HPS cases in central Argentina, suggests that human populations are at risk of HPS disease, although there were not reported cases of this disease until today.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Hantavirus/veterinária , Orthohantavírus/imunologia , Doenças dos Roedores/epidemiologia , Animais , Antígenos Virais/imunologia , Argentina/epidemiologia , Reservatórios de Doenças , Feminino , Orthohantavírus/classificação , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Síndrome Pulmonar por Hantavirus/transmissão , Humanos , Masculino , Prevalência , Doenças dos Roedores/virologia , Roedores/classificação , Roedores/virologia , Estações do Ano
7.
Mem. Inst. Oswaldo Cruz ; 98(6): 727-732, Sept. 2003. ilus, tab, mapas
Artigo em Inglês | LILACS | ID: lil-348338

RESUMO

We studied hantavirus seroprevalence and virus variability in rodent populations in Diego Gaynor, northwest of Buenos Aires province, Argentina. Rodent samplings were conducted in railroads and cropfield borders in March and July 1999, September and December 2000, and March 2001. Antibody detection was performed by an enzyme link immunosorbent assay (ELISA), using the recombinant nucleoprotein of Andes (AND) virus as antigen. Tissue samples were taken from positive antibody individuals in order to confirm the presence of hantavirus genomic material and to identify virus genotypes. Akodon azarae was the most abundant species, followed by Oligoryzomys flavescens, while Calomys laucha and C. musculinus were rarely caught. We found a rate of seroprevalence of 9.3 percent for a total sample of 291 A. azarae and 13.5 percent for 37 O. flavescens. After molecular analyses of hantavirus, we confirmed the presence of hantavirus genomic material in 16 individuals with ELISA (+) results and two individuals with ELISA (-). Four amplimers for each species were sequenced and compared to the corresponding sequences of representative hantaviruses. We identified the AND Cent Lec from three O. flavescens, and the Pergamino virus from four A. azarae and from one O. flavescens. A. azarae males had higher seroprevalence than females, and heavier individuals showed higher seroprevalence than lighter ones. We did not find seroprevalence differences according to sex in O. flavescens, although this result may have been produced by the low sample size. The lowest seroprevalence was found in a period of high rodent density, when juveniles prevailed in the population. We found higher seroprevalences than those detected in previous studies for other localities of central Argentina where cases of hantavirus pulmonary syndrome (HPS) have been reported. The presence of AND Cent Lec virus in rodent populations of the study area, which is responsible of HPS cases in central Argentina, suggests that human populations are at risk of HPS disease, although there were not reported cases of this disease until today


Assuntos
Animais , Humanos , Masculino , Feminino , Anticorpos Antivirais , Antígenos Virais , Orthohantavírus , Infecções por Hantavirus , Doenças dos Roedores , Argentina , Reservatórios de Doenças , Ensaio de Imunoadsorção Enzimática , Orthohantavírus , Infecções por Hantavirus , Síndrome Pulmonar por Hantavirus/transmissão , Prevalência , Doenças dos Roedores , Roedores , Estações do Ano , Estudos Soroepidemiológicos
8.
Medicina (B Aires) ; 62(1): 1-8, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-11965841

RESUMO

This paper analyzed the prevalence and distribution of serological reactivity to hantavirus (antibody against ANDES virus) of human population exposed to hantavirus and rodents trapped in the studied area. This study was developed in Salta (Orán and San Martín Departments), area with the highest incidence for Hantavirus Pulmonary Syndrome (HPS) in Argentina. In December 1997, 453 healthy people were studied by serology and 39 rodents by serology and PCR. The studied individuals were distributed as: 145 farm inhabitants (FI), 212 people living in the same dwelling with healthy individuals (controls) (Cco), 87 people living in the same dwelling with persons undergoing SPH in 1997 (cases) (Cca). Moreover, 19 physicians and nurses who cared for patients with SPH in 1997 were also studied. The prevalence of hantavirus infection among the studied population was 6.3%. The prevalence was 10.3% among FI, 6.9% among Cca and 3.3% among Cco (p < 0.02). There was no serological reactivity among PS. The prevalence in 39 trapped rodents was 10.2%, with infection only for Oligoryzomys chacoensis, O. flavescens and Akodon varius species. The prevalence of human cases with asymptomatic infection in Salta is higher than in other regions of the country, and we are presenting a hypothesis to explain these differences. The analyzed data suggest that in this region up to the time this study was performed, there would not have been person to person transmission of hantavirus. The transmission would be from rodent contact exclusively and mainly in ongoing deforestation areas and domestic habitat surrounding rural dwellings.


Assuntos
Doenças Endêmicas , Síndrome Pulmonar por Hantavirus/epidemiologia , Orthohantavírus/isolamento & purificação , Adolescente , Adulto , Idoso , Animais , Anticorpos Antivirais/sangue , Argentina/epidemiologia , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Reservatórios de Doenças , Feminino , Síndrome Pulmonar por Hantavirus/sangue , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Roedores/virologia , Estudos Soroepidemiológicos
9.
Medicina (B.Aires) ; 62(1): 1-8, 2002. mapas, tab, graf
Artigo em Espanhol | LILACS | ID: lil-314489

RESUMO

This paper analyzed the prevalence and distribution of serological reactivity to hantavirus (antibody against ANDES virus) of human population exposed to hantavirus and rodents trapped in the studied area. This study was developed in Salta (Oran and San Martin Departments), area with the highest incidence for Hantavirus Pulmonary Syndrome (HPS) in Argentina. In December 1997, 453 healthy people were studied by serology and 39 rodents by serology and PCR. The studied individuals were distributed as: 145 farm inhabitants (FI), 212 people living in the same dwelling with healthy individuals (controls) (Cco), 87 people living in the same dwelling with persons undergoing SPH in 1997 (cases) (Cca). Moreover, 19 physicians and nurses who cared for patients with SPH in 1997 were also studied. The prevalence of hantavirus infection among the studied population was 6.3 percent. The prevalence was 10.3 percent among FI, 6.9 percent among Cca and 3.3 percent among Cco (p < 0.02). There was no serological reactivity among PS. The prevalence in 39 trapped rodents was 10.2 percent, with infection only for Oligoryzomys chacoensis, O. flavescens and Akodon varius species.The prevalence of human cases with asymptomatic infection in Salta is higher than in other regions of the country, and we are presenting a hypothesis to explain these differences. The analyzed data suggest that in this region up to the time this study was performed, there would not have been person to person transmission of hantavirus. The transmission would be from rodent contact exclusively and mainly in ongoing deforestation areas and domestic habitat surrounding rural dwellings.


Assuntos
Animais , Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Doenças Endêmicas , Orthohantavírus , Síndrome Pulmonar por Hantavirus/epidemiologia , Anticorpos Antivirais , Argentina , Distribuição de Qui-Quadrado , Reservatórios de Doenças , Síndrome Pulmonar por Hantavirus/sangue , Incidência , Reação em Cadeia da Polimerase , Prevalência , Roedores , Estudos Soroepidemiológicos
10.
Medicina [B Aires] ; 62(1): 1-8, 2002.
Artigo em Espanhol | BINACIS | ID: bin-39264

RESUMO

This paper analyzed the prevalence and distribution of serological reactivity to hantavirus (antibody against ANDES virus) of human population exposed to hantavirus and rodents trapped in the studied area. This study was developed in Salta (Orán and San Martín Departments), area with the highest incidence for Hantavirus Pulmonary Syndrome (HPS) in Argentina. In December 1997, 453 healthy people were studied by serology and 39 rodents by serology and PCR. The studied individuals were distributed as: 145 farm inhabitants (FI), 212 people living in the same dwelling with healthy individuals (controls) (Cco), 87 people living in the same dwelling with persons undergoing SPH in 1997 (cases) (Cca). Moreover, 19 physicians and nurses who cared for patients with SPH in 1997 were also studied. The prevalence of hantavirus infection among the studied population was 6.3


. The prevalence was 10.3


among FI, 6.9


among Cca and 3.3


among Cco (p < 0.02). There was no serological reactivity among PS. The prevalence in 39 trapped rodents was 10.2


, with infection only for Oligoryzomys chacoensis, O. flavescens and Akodon varius species. The prevalence of human cases with asymptomatic infection in Salta is higher than in other regions of the country, and we are presenting a hypothesis to explain these differences. The analyzed data suggest that in this region up to the time this study was performed, there would not have been person to person transmission of hantavirus. The transmission would be from rodent contact exclusively and mainly in ongoing deforestation areas and domestic habitat surrounding rural dwellings.

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