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1.
J Antimicrob Chemother ; 74(3): 722-730, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30517632

RESUMO

OBJECTIVES: To assess the prevalence and patterns of pre-treatment HIV drug resistance (PDR) and HIV-1 subtype in infants from Argentina with exposure to different antiretroviral drugs (ARVs) for the prevention of mother-to-child transmission (PMTCT). PATIENTS AND METHODS: HIV-1 genotyping was performed in 115 infants (median age = 2.3 months) born between 2007 and 2014 to screen for drug resistance mutations (DRMs) before starting first-line ART. HIV-1 subtype was characterized by phylogenetic and recombination analysis. RESULTS: Overall, DRMs were found in 34 of 115 infants (PDR level 30% to any ARV, 3.5% to PIs, 12% to NRTIs and 22% to NNRTIs). Of the 115 infants, 22 (19.1%) were ARV-unexposed. Another 93 were ARV-exposed: 28 (24.3%) to short-course zidovudine monotherapy ARV prophylaxis; 25 (21.7%) to nevirapine-based ARV prophylaxis; 12 (10.4%) to perinatal infant zidovudine prophylaxis + maternal combination ART with NNRTIs; and 28 (24.3%) to perinatal infant zidovudine prophylaxis+maternal combination ART with PIs. Transmitted drug resistance among ARV-unexposed infants was 32% (5% to PIs, 9% to NRTIs and 18% to NNRTIs). ART-exposed infants showed multi-class ARV resistance. Importantly, vertical transmission of a triple-class-resistant virus was confirmed in one case. Patterns of DRMs predicted high-level resistance to NNRTIs in a similar and high proportion (>50%) of infants with at least one DRM independently of ARV exposure. BF recombinants were found in 74%, subtype B in 20%, subtype C in 3% and novel AG and AB recombinants in 3%. CONCLUSIONS: PDR in HIV-1-infected children from Argentina is among the highest reported, jeopardizing successful lifelong suppressive ART as well as the efficacy of current PMTCT regimens.


Assuntos
Farmacorresistência Viral , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Argentina/epidemiologia , Feminino , Genótipo , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , Humanos , Lactente , Masculino , Mutação , Prevalência , Vigilância em Saúde Pública , Fatores de Risco , Produtos do Gene pol do Vírus da Imunodeficiência Humana
2.
Antivir Ther ; 22(7): 625-629, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28234630

RESUMO

BACKGROUND: Rilpivirine-based regimens are now preferred or alternative first-line regimens according to many HIV treatment guidelines. Recently, a surveillance study conducted in Argentina determined that prevalence of pretreatment resistance to first-generation non-nucleoside reverse transcriptase inhibitors (NNRTIs) was 10%. The aim of this study was to analyse the prevalence of resistance mutations to newer generation NNRTIs in the population starting ART in Argentina. METHODS: We analysed the prevalence of resistance mutations to rilpivirine and etravirine (according to the IAS list), obtained through a nationally representative pretreatment HIV-drug resistance (PDR) surveillance study performed in Argentina in 2014-2015. Briefly, 25 ART-dispensing sites throughout the country were randomly chosen to enrol 330 adults starting ART. Samples were processed with Trugene (Siemens)® and analysed using the Stanford algorithm. RESULTS: All 270 samples corresponding to participants with no prior exposure to antiretroviral drugs were included in this analysis. Median (IQR) age was 35 years (28-43); 66.7% were male; median (IQR) CD4+ T-cell count was 284 cells/mm3 (112-489). The prevalence of resistance to any antiretroviral was 16% (±5%) and prevalence of NNRTI RAMs was 13% (±4%). The prevalence of resistance to rilpivirine was 8% (±3%). Prevalence of resistance to etravirine was 4% (±3%). The most frequent mutations conferring resistance to rilpivirine were: E138A (n=6) and G190A (n=4). CONCLUSIONS: This PDR surveillance study showed concerning levels of HIV drug resistance (HIVDR) in Argentina, not only for first-generation NNRTIs but also to rilpivirine. In our setting, performing resistance testing would be necessary before prescription of ART even if a second-generation NNRTI-based regimen was used as first-line therapy.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Argentina/epidemiologia , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Vigilância em Saúde Pública , Carga Viral
3.
Rev. argent. microbiol ; 47(1): 57-61, Mar. 2015.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1171813

RESUMO

La transmisión vertical es la principal vía de contagio del HIV en la edad pediátrica. El diagnóstico de la infección congénita antes de los 18meses se realiza mediante ensayos virológicos: detección de genoma viral como ARN plasmático y ADN proviral. La sensibilidad de estos ensayos varía según la edad del niño, con valores de especificidad mayores al 95%. El objetivo de este trabajo fue evaluar el desempeño del ensayo de carga viral (CV) COBAS Taqman HIV-1 Test, v1.0 (Roche), y su concordancia con una PCR múltiple anidada in-house para la detección del ADN proviral. De 341 muestras procesadas, 15 resultaron positivas y 326 negativas por ambas metodologías. Para la metodología de CV, la sensibilidad general fue del 88,2% y la especificidad del 100%. Nuestros resultados indican que la metodología de CV evaluada puede utilizarse como técnica alternativa para el diagnóstico de infección congénita por HIV


Vertical transmission is the main route of HIV infection in childhood. Because of the persistence of maternal HIV antibodies, virologic assays that directly detect HIV are required to diagnose HIV infection in infants younger than 18months of age. The sensitivity of HIV RNA/DNA assays increases as the child becomes older. These tests have specificity values greater than 95%. The aim of this study was to evaluate the performance of the COBAS Taqman HIV-1 Test, v1.0 assay (Roche) and its concordance with a Multiplex Nested-PCR. Of 341 samples processed, 15 were positive and 326 negative by both methods. Sensitivity and specificity overall values for the viral load assay were 88.2% and 100%, respectively. Our results indicate that the COBAS Taqman assay evaluated could be used as an alternative method to diagnose HIV congenital infection


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Síndrome da Imunodeficiência Adquirida/congênito , Carga Viral/genética , Kit de Reagentes para Diagnóstico/estatística & dados numéricos , Síndrome da Imunodeficiência Adquirida/diagnóstico , Carga Viral/métodos
4.
Rev Argent Microbiol ; 47(1): 57-61, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-25686652

RESUMO

Vertical transmission is the main route of HIV infection in childhood. Because of the persistence of maternal HIV antibodies, virologic assays that directly detect HIV are required to diagnose HIV infection in infants younger than 18 months of age. The sensitivity of HIV RNA/DNA assays increases as the child becomes older. These tests have specificity values greater than 95%. The aim of this study was to evaluate the performance of the COBAS Taqman HIV-1 Test, v1.0 assay (Roche) and its concordance with a Multiplex Nested-PCR. Of 341 samples processed, 15 were positive and 326 negative by both methods. Sensitivity and specificity overall values for the viral load assay were 88.2% and 100%, respectively. Our results indicate that the COBAS Taqman assay evaluated could be used as an alternative method to diagnose HIV congenital infection.


Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas , Sorodiagnóstico da AIDS , Infecções por HIV/virologia , Humanos , Lactente , Recém-Nascido , Reação em Cadeia da Polimerase , Carga Viral
5.
Rev. Argent. Microbiol. ; 47(1): 57-61, 2015 Jan-Mar.
Artigo em Espanhol | BINACIS | ID: bin-133760

RESUMO

Vertical transmission is the main route of HIV infection in childhood. Because of the persistence of maternal HIV antibodies, virologic assays that directly detect HIV are required to diagnose HIV infection in infants younger than 18months of age. The sensitivity of HIV RNA/DNA assays increases as the child becomes older. These tests have specificity values greater than 95


. The aim of this study was to evaluate the performance of the COBAS Taqman HIV-1 Test, v1.0 assay (Roche) and its concordance with a Multiplex Nested-PCR. Of 341 samples processed, 15 were positive and 326 negative by both methods. Sensitivity and specificity overall values for the viral load assay were 88.2


and 100


, respectively. Our results indicate that the COBAS Taqman assay evaluated could be used as an alternative method to diagnose HIV congenital infection.

6.
Rev Argent Microbiol ; 46(3): 196-200, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-25444127

RESUMO

The introduction of nucleic acid amplification techniques (NAT) in blood banks was intended to reduce the residual risk of transfusion-transmitted infections. Co-circulation of a great diversity of HIV-1 variants in Argentina portrays the need to assess the sensitivity of serological and molecular assays available for their detection. In this study, we evaluated the sensitivity of the COBAS AmpliScreen™ HIV-1 Test, version 1.5 (Roche) for the detection of HIV-1 RNA in plasma samples of infected individuals from Argentina. The results of this study reveal that this technique has high sensitivity for the detection of HIV-1 RNA under assay conditions: using mini-pool testing, pools ≥ 50 RNA copies per ml achieved ≥ 92 % sensitivity, whereas in the standard procedure, samples ≥ 207 RNA copies/ml achieved 100 % sensitivity. Moreover, the COBAS AmpliScreen™ HIV-1 Test, version 1.5 (Roche) is suitable for detecting prevailing HIV-1 variants.


Assuntos
Colorimetria/métodos , Infecções por HIV/virologia , HIV-1/isolamento & purificação , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Viremia/virologia , Argentina/epidemiologia , Segurança do Sangue , Técnicas de Genotipagem , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/genética , Humanos , Programas de Rastreamento/métodos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Ultracentrifugação , Carga Viral
7.
Rev. argent. microbiol ; 46(3): 196-200, oct. 2014.
Artigo em Espanhol | LILACS | ID: biblio-1008778

RESUMO

Las técnicas de amplificación de ácidos nucleicos (NAT) se incorporaron en los bancos de sangre para reducir el riesgo residual de transmisión de infecciones por vía transfusional. La cocirculación de distintas variantes del HIV-1 en Argentina indica la necesidad de evaluar la sensibilidad de los ensayos serológicos y moleculares disponibles para su detección. En este trabajo se evaluó la sensibilidad del equipo COBAS AmpliScreenTM HIV-1 Test, versión 1.5 (Roche), para detectar ARN viral en plasmas de individuos infectados con HIV-1 de Argentina. Los resultados demuestran que esta técnica tiene una alta sensibilidad para detectar ARN de HIV-1 en las condiciones ensayadas: para ensayo de mini-pooles (pooles ≥ 50 copias de ARN/ml), la sensibilidad fue ≥ 92 %, y para procedimiento estándar (plasmas ≥ 207 copias de ARN/ml), la sensibilidad fue 100 %. Además, la técnica COBAS AmpliScreenTM HIV-1 Test, versión 1.5 (Roche), es adecuada para la detección de las variantes de HIV-1 prevalentes


The introduction of nucleic acid amplification techniques (NAT) in blood banks was intended to reduce the residual risk of transfusion-transmitted infections. Co-circulation of a great diversity of HIV-1 variants in Argentina portrays the need to assess the sensitivity of serological and molecular assays available for their detection. In this study, we evaluated the sensitivity of the COBAS AmpliScreenTM HIV-1 Test, version 1.5 (Roche) for the detection of HIV-1 RNA in plasma samples of infected individuals from Argentina. The results of this study reveal that this technique has high sensitivity for the detection of HIV-1 RNA under assay conditions: using mini-pool testing, pools ≥ 50 RNA copies per ml achieved ≥ 92 % sensitivity, whereas in the standard procedure, samples ≥ 207 RNA copies/ ml achieved 100 % sensitivity. Moreover, the COBAS AmpliScreenTM HIV-1 Test, version 1.5 (Roche) is suitable for detecting prevailing HIV-1 variants


Assuntos
Humanos , HIV-1/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecções por HIV/sangue
8.
Rev. Argent. Microbiol. ; 46(3): 196-200, 2014 Jul-Sep.
Artigo em Espanhol | BINACIS | ID: bin-133302

RESUMO

The introduction of nucleic acid amplification techniques (NAT) in blood banks was intended to reduce the residual risk of transfusion-transmitted infections. Co-circulation of a great diversity of HIV-1 variants in Argentina portrays the need to assess the sensitivity of serological and molecular assays available for their detection. In this study, we evaluated the sensitivity of the COBAS AmpliScreen HIV-1 Test, version 1.5 (Roche) for the detection of HIV-1 RNA in plasma samples of infected individuals from Argentina. The results of this study reveal that this technique has high sensitivity for the detection of HIV-1 RNA under assay conditions: using mini-pool testing, pools  50 RNA copies per ml achieved  92


sensitivity, whereas in the standard procedure, samples  207 RNA copies/ml achieved 100


sensitivity. Moreover, the COBAS AmpliScreenÔäó HIV-1 Test, version 1.5 (Roche) is suitable for detecting prevailing HIV-1 variants.


Assuntos
Colorimetria/métodos , Infecções por HIV/virologia , HIV-1/isolamento & purificação , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Viremia/virologia , Argentina/epidemiologia , Segurança do Sangue , Técnicas de Genotipagem , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/genética , Humanos , Programas de Rastreamento/métodos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Ultracentrifugação , Carga Viral
9.
Rev Argent Microbiol ; 44(1): 26-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22610294

RESUMO

At the time of influenza A (H1N1) emergency, the WHO responded with remarkable speed by releasing guidelines and a protocol for a real-time RT-PCR assay (rRT-PCR). The aim of the present study was to evalúate the performance of the "Real Time Ready Influenza A/H1N1 Detection Set" (June 2009)-Roche kit in comparison to the CDC reference rRT-PCR protocol. The overall sensitivity of the Roche assay for detection of the Inf A gene in the presence or absence of the H1 gene was 74.5 %. The sensitivity for detecting samples that were only positive for the Inf A gene (absence of the H1 gene) was 53.3 % whereas the sensitivity for H1N1-positive samples (presence of the Inf A gene and any other swine gene) was 76.4 %. The specificity of the assay was 97.1 %. A new version of the kit (November 2009) is now available, and a recent evaluation of its performance showed good sensitivity to detect pandemic H1N1 compared to other molecular assays.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Kit de Reagentes para Diagnóstico , Argentina/epidemiologia , Centers for Disease Control and Prevention, U.S. , Surtos de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Cavidade Nasal/virologia , Proteínas do Nucleocapsídeo , Faringe/virologia , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos , Proteínas do Core Viral/genética
10.
Rev. argent. microbiol ; 44(1): 0-0, mar. 2012. tab
Artigo em Inglês | LILACS | ID: lil-639714

RESUMO

At the time of influenza A (H1N1) emergency, the WHO responded with remarkable speed by releasing guidelines and a protocol for a real-time RT-PCR assay (rRT-PCR). The aim of the present study was to evalúate the performance of the "Real Time Ready Influenza A/H1N1 Detection Set" (June 2009)-Roche kit in comparison to the CDC reference rRT-PCR protocol. The overall sensitivity of the Roche assay for detection of the Inf A gene in the presence or absence of the H1 gene was 74.5 %. The sensitivity for detecting samples that were only positive for the Inf A gene (absence of the H1 gene) was 53.3 % whereas the sensitivity for H1N1-positive samples (presence of the Inf A gene and any other swine gene) was 76.4 %. The specificity of the assay was 97.1 %. A new version of the kit (November 2009) is now available, and a recent evaluation of its performance showed good sensitivity to detect pandemic H1N1 compared to other molecular assays.


Durante la pandemia de influenza A (H1N1), la OMS recomendó algoritmos y protocolos de detección del virus mediante RT-PCR en tiempo real. El objetivo del presente estudio fue evaluar el desempeño del equipo que comercializa la empresa Roche, Real Time Ready Influenza A/H1N1 Detection Set (junio de 2009), en comparación con el protocolo de RT-PCR en tiempo real de los CDC. La sensibilidad global del ensayo de Roche para la detección del gen Inf A en presencia o ausencia del gen H1 fue 74,5 %. La sensibilidad para la detección de muestras positivas solo para el gen Inf A (ausencia del gen H1) fue 53,3 % y la sensibilidad para la detección de muestras positivas para H1N1 (presencia del gen Inf A y cualquier otro gen porcino) fue 76,4 %. La especificidad fue 97,1 %. Existe una nueva versión del equipo (noviembre 2009) que, según se ha descrito, presenta buena sensibilidad en comparación con otros ensayos moleculares para detectar H1N1 pandémica.


Assuntos
Humanos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Kit de Reagentes para Diagnóstico , Argentina/epidemiologia , Centers for Disease Control and Prevention, U.S. , Surtos de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Cavidade Nasal/virologia , Faringe/virologia , Reprodutibilidade dos Testes , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Estados Unidos , Proteínas do Core Viral/genética
11.
Rev. argent. microbiol ; 44(1): 0-0, Mar. 2012. tab
Artigo em Inglês | BINACIS | ID: bin-129554

RESUMO

At the time of influenza A (H1N1) emergency, the WHO responded with remarkable speed by releasing guidelines and a protocol for a real-time RT-PCR assay (rRT-PCR). The aim of the present study was to evalúate the performance of the "Real Time Ready Influenza A/H1N1 Detection Set" (June 2009)-Roche kit in comparison to the CDC reference rRT-PCR protocol. The overall sensitivity of the Roche assay for detection of the Inf A gene in the presence or absence of the H1 gene was 74.5 %. The sensitivity for detecting samples that were only positive for the Inf A gene (absence of the H1 gene) was 53.3 % whereas the sensitivity for H1N1-positive samples (presence of the Inf A gene and any other swine gene) was 76.4 %. The specificity of the assay was 97.1 %. A new version of the kit (November 2009) is now available, and a recent evaluation of its performance showed good sensitivity to detect pandemic H1N1 compared to other molecular assays.(AU)


Durante la pandemia de influenza A (H1N1), la OMS recomendó algoritmos y protocolos de detección del virus mediante RT-PCR en tiempo real. El objetivo del presente estudio fue evaluar el desempeño del equipo que comercializa la empresa Roche, Real Time Ready Influenza A/H1N1 Detection Set (junio de 2009), en comparación con el protocolo de RT-PCR en tiempo real de los CDC. La sensibilidad global del ensayo de Roche para la detección del gen Inf A en presencia o ausencia del gen H1 fue 74,5 %. La sensibilidad para la detección de muestras positivas solo para el gen Inf A (ausencia del gen H1) fue 53,3 % y la sensibilidad para la detección de muestras positivas para H1N1 (presencia del gen Inf A y cualquier otro gen porcino) fue 76,4 %. La especificidad fue 97,1 %. Existe una nueva versión del equipo (noviembre 2009) que, según se ha descrito, presenta buena sensibilidad en comparación con otros ensayos moleculares para detectar H1N1 pandémica.(AU)


Assuntos
Humanos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Kit de Reagentes para Diagnóstico , Argentina/epidemiologia , Centers for Disease Control and Prevention, U.S. , Surtos de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Cavidade Nasal/virologia , Faringe/virologia , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos , Proteínas do Core Viral/genética
12.
Rev. argent. microbiol ; 44(1): 0-0, Mar. 2012. tab
Artigo em Inglês | BINACIS | ID: bin-127730

RESUMO

At the time of influenza A (H1N1) emergency, the WHO responded with remarkable speed by releasing guidelines and a protocol for a real-time RT-PCR assay (rRT-PCR). The aim of the present study was to evalúate the performance of the "Real Time Ready Influenza A/H1N1 Detection Set" (June 2009)-Roche kit in comparison to the CDC reference rRT-PCR protocol. The overall sensitivity of the Roche assay for detection of the Inf A gene in the presence or absence of the H1 gene was 74.5 %. The sensitivity for detecting samples that were only positive for the Inf A gene (absence of the H1 gene) was 53.3 % whereas the sensitivity for H1N1-positive samples (presence of the Inf A gene and any other swine gene) was 76.4 %. The specificity of the assay was 97.1 %. A new version of the kit (November 2009) is now available, and a recent evaluation of its performance showed good sensitivity to detect pandemic H1N1 compared to other molecular assays.(AU)


Durante la pandemia de influenza A (H1N1), la OMS recomendó algoritmos y protocolos de detección del virus mediante RT-PCR en tiempo real. El objetivo del presente estudio fue evaluar el desempeño del equipo que comercializa la empresa Roche, Real Time Ready Influenza A/H1N1 Detection Set (junio de 2009), en comparación con el protocolo de RT-PCR en tiempo real de los CDC. La sensibilidad global del ensayo de Roche para la detección del gen Inf A en presencia o ausencia del gen H1 fue 74,5 %. La sensibilidad para la detección de muestras positivas solo para el gen Inf A (ausencia del gen H1) fue 53,3 % y la sensibilidad para la detección de muestras positivas para H1N1 (presencia del gen Inf A y cualquier otro gen porcino) fue 76,4 %. La especificidad fue 97,1 %. Existe una nueva versión del equipo (noviembre 2009) que, según se ha descrito, presenta buena sensibilidad en comparación con otros ensayos moleculares para detectar H1N1 pandémica.(AU)


Assuntos
Humanos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Kit de Reagentes para Diagnóstico , Argentina/epidemiologia , Centers for Disease Control and Prevention, U.S. , Surtos de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Cavidade Nasal/virologia , Faringe/virologia , RNA Viral/genética , Proteínas de Ligação a RNA/genética , /métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos , Proteínas do Core Viral/genética
13.
Neuropsychopharmacology ; 30(1): 58-66, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15496941

RESUMO

Corticosterone (CS) has been shown to regulate behavior in the learned helplessness (LH) paradigm. Here we provide evidence for a U-shaped relationship between the increasing doses of CS administered and escape failures in the LH model. Replacement with CS (20-400 microg/ml in drinking water) in adrenalectomized (ADX) animals was utilized to examine how the selective activation of mineralocorticoid (MR) and glucocorticoid (GR) receptors is related to the behavioral impairments induced by inescapable shock (IS). Available MR and GR levels were determined in hippocampal cytosol by radioligand binding assays. Non-CS replaced ADX animals showed a high percentage of escape failures assessed 48 h after IS. A CS does of 100 microg/ml given to ADX animals markedly reduced escape failures and resulted in an almost total reduction of available MR associated with a partial reduction of GR. However, the administration of aldosterone (ALDO), a selective MR agonist, was not sufficient to restore normal coping behavior. Moreover, an important role for GR was further shown by means of the specific GR antagonist, RU 38486, which blocked the reduction of LH in ADX rats that were given 100 microg/ml CS. Higher doses of CS given to ADX rats reinstated the LH behavior, and SHAM rats that produced stress CS levels also produced LH behavior. The results indicate a U-shaped dose response function with both negligible and high CS levels being associated with LH behavior. Hence, along with a moderate reduction of available GR level in the cytosol, a large decrease in MR availability seems to be necessary to prevent the acquisition and expression of LH. However, very high reduction of available GR is associated with LH behavior.


Assuntos
Glândulas Suprarrenais/fisiologia , Comportamento Animal/efeitos dos fármacos , Desamparo Aprendido , Esteroides/farmacologia , Aldosterona/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Corticosterona/metabolismo , Corticosterona/farmacologia , Citosol/efeitos dos fármacos , Citosol/metabolismo , Relação Dose-Resposta a Droga , Eletrochoque , Antagonistas de Hormônios/farmacologia , Bombas de Infusão Implantáveis , Masculino , Mifepristona/farmacologia , Antagonistas de Receptores de Mineralocorticoides , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores de Glucocorticoides/antagonistas & inibidores , Estresse Psicológico/psicologia
14.
Nutr Neurosci ; 5(1): 53-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11929198

RESUMO

The present work sought to study the binding properties of central mu-opiate receptors in whole brain and in different central areas in adult rats undernourished at perinatal age. Rats were undernourished with a hypoproteic diet containing 8% casein from day 14 of gestation until 50 days of age. The animals were thereafter fed a balanced commercial chow until 140 days of age. At this time point the experiments started. 3H-D-Ala2, N-Me-Phe4, Gly5-ol-enkephalin (3H-DAMGO) was used to selectively label the mu-receptors. The results obtained demonstrated that perinatal undernutrition induced, in the adult animal, a decreased mu-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in mu-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of mu-opiate receptors in the brain.


Assuntos
Animais Recém-Nascidos , Encéfalo/metabolismo , Proteínas Alimentares/administração & dosagem , Efeitos Tardios da Exposição Pré-Natal , Deficiência de Proteína/complicações , Receptores Opioides mu/metabolismo , Analgesia , Animais , Caseínas/administração & dosagem , Ala(2)-MePhe(4)-Gly(5)-Encefalina/metabolismo , Feminino , Idade Gestacional , Masculino , Gravidez , Ratos , Ratos Wistar , Estresse Fisiológico , Trítio
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