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1.
J Virol Methods ; 323: 114839, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37923063

RESUMO

Studies reporting the expression of hepatitis A virus (HAV) structural proteins, specifically recombinant VP1-2A containing an immunogenic activity, use the Escherichia coli system. Recombinant HAV proteins may represent a source of less expensive antigens for application in different diagnostic platforms. However, the formation of insoluble aggregates is an obstacle to obtaining large amounts of HAV proteins in their native form. To overcome this obstacle, some approaches were applied in this study to improve purification, solubility, and protein expression levels. Critical properties were evaluated. The introduction of another insertion codon to increase the protein concentration and vector activity was observed and verified by SDS-PAGE. The expression was established with 0.4 mM IPTG for 4 h at 37 °C. The VP1 protein was partially soluble at an isoeletric point (pI) of 6.45. The majority of HAV VP1-2A proteins measured 45.19 kDa in size and had a homogeneity of 53.58%. Multi-antigen print immunoassay (MAPIA) showed antigenicity at different HAV VP1-2A concentrations, and microsphere-based immunoassays showed a specificity of 100% and a sensitivity of 84%. HAV VP1-2A was characterized using different sensitivity methods to prove its biological activity, indicating its use as a tool for the diagnosis of Hepatitis A virus infection.


Assuntos
Vírus da Hepatite A , Hepatite A , Humanos , Vírus da Hepatite A/genética , Proteínas Recombinantes , Hepatite A/diagnóstico
2.
Protein Expr Purif ; 207: 106263, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36921810

RESUMO

COVID-19 pandemic was caused by the severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2). The nucleocapsid (N) protein from Sars-CoV-2 is a highly immunogenic antigen and responsible for genome packing. Serological assays are important tools to detect previous exposure to SARS-CoV-2, complement epidemiological studies, vaccine evaluation and also in COVID-19 surveillance. SARS-CoV-2 N (r2N) protein was produced in Escherichia coli, characterized, and the immunological performance was evaluated by enzyme-linked immunosorbent assay (ELISA) and beads-based array immunoassay. r2N protein oligomers were evidenced when it is associated to nucleic acid. Benzonase treatment reduced host nucleic acid associated to r2N protein, but crosslinking assay still demonstrates the presence of higher-order oligomers. Nevertheless, after RNase treatment the higher-order oligomers reduced, and dimer form increased, suggesting RNA contributes to the oligomer formation. Structural analysis revealed nucleic acid did not interfere with the thermal stability of the recombinant protein. Interestingly, nucleic acid was able to prevent r2N protein aggregation even with increasing temperature while the protein benzonase treated begin aggregation process above 55 °C. In immunological characterization, ELISA performed with 233 serum samples presented a sensitivity of 97.44% (95% Confidence Interval, CI, 91.04%, 99.69%) and a specificity of 98.71% (95% CI, 95.42%, 99.84%) while beads-based array immunoassay carried out with 217 samples showed 100% sensitivity and 98.6% specificity. The results exhibited an excellent immunological performance of r2N protein in serologic assays showing that, even in presence of nucleic acid, it can be used as a component of an immunoassay for the sensitive and specific detection of SARS-CoV-2 antibodies.


Assuntos
COVID-19 , Ácidos Nucleicos , Humanos , COVID-19/diagnóstico , Proteínas do Nucleocapsídeo/genética , SARS-CoV-2/genética , Teste para COVID-19 , Pandemias , Sensibilidade e Especificidade , Nucleocapsídeo , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Antivirais , Proteínas Recombinantes/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-30972305

RESUMO

Despite the increasing number of studies concerning insect immunity, Lutzomyia longipalpis immune responses in the presence of Leishmania infantum chagasi infection has not been widely investigated. The few available studies analyzed the role of the Toll and IMD pathways involved in response against Leishmania and microbial infections. Nevertheless, effector molecules responsible for controlling sand fly infections have not been identified. In the present study we investigated the role a signal transduction pathway, the Transforming Growth Factor-beta (TGF-ß) pathway, on the interrelation between L. longipalpis and L. i. chagasi. We identified an L. longipalpis homolog belonging to the multifunctional cytokine TGF-ß gene family (LlTGF-ß), which is closely related to the activin/inhibin subfamily and potentially involved in responses to infections. We investigated this gene expression through the insect development and in adult flies infected with L. i. chagasi. Our results showed that LlTGF-ß was expressed in all L. longipalpis developmental stages and was upregulated at the third day post L. i. chagasi infection, when protein levels were also higher as compared to uninfected insects. At this point blood digestion is finished and parasites are in close contact with the insect gut. In addition, we investigated the role of LlTGF-ß on L. longipalpis infection by L. i. chagasi using either gene silencing by RNAi or pathway inactivation by addition of the TGF-ß receptor inhibitor SB431542. The blockage of the LlTGF-ß pathway increased significantly antimicrobial peptides expression and nitric oxide levels in the insect gut, as expected. Both methods led to a decreased L. i. chagasi infection. Our results show that inactivation of the L. longipalpis TGF-ß signal transduction pathway reduce L. i. chagasi survival, therefore suggesting that under natural conditions the parasite benefits from the insect LlTGF-ß pathway, as already seen in Plamodium infection of mosquitoes.


Assuntos
Interações Hospedeiro-Patógeno , Insetos Vetores/parasitologia , Leishmania infantum/crescimento & desenvolvimento , Psychodidae/parasitologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Perfilação da Expressão Gênica , Imunidade Inata , Insetos Vetores/imunologia , Psychodidae/imunologia , Transdução de Sinais , Análise de Sobrevida
4.
PLoS One ; 11(12): e0167669, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27936034

RESUMO

The use of antibodies in immunodiagnostic kits generally implies the conjugation of these proteins with other molecules such as chromophores or fluorochromes. The development of more sensitive quality control procedures than spectrophotometry is essential to assure the use of better fluorescent conjugates since the fluorescent conjugates are critical reagents for a variety of immunodiagnostic kits. In this article, we demonstrate a new flow cytometric protocol to evaluate conjugates by molecules of equivalent soluble fluorochromes (MESF) and by traditional flow cytometric analysis. We have coupled microspheres with anti-IgG-PE and anti-HBSAg-PE conjugates from distinct manufactures and/or different lots and evaluated by flow cytometry. Their fluorescence intensities were followed for a period of 18 months. Our results showed that there was a great difference in the fluorescence intensities between the conjugates studied. The differences were observed between manufactures and lots from both anti-IgG-PE and anti-HBSAg-PE conjugates. Coefficients of variation (CVs) showed that this parameter can be used to determine better coupling conditions, such as homogenous coupling. The MESF analysis, as well as geometric mean evaluation by traditional flow cytometry, showed a decrease in the values for all conjugates during the study and were indispensable tools to validate the results of stability tests. Our data demonstrated the feasibility of the flow cytometric method as a standard quality control of immunoassay kits.


Assuntos
Anticorpos Imobilizados/química , Citometria de Fluxo/métodos , Corantes Fluorescentes/química , Imunoensaio/métodos , Imunoconjugados/química , Animais , Anticorpos Anti-Idiotípicos/química , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Fluoresceína-5-Isotiocianato/química , Fluorescência , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Imunoconjugados/imunologia , Imunoglobulina G/imunologia , Microesferas , Ficoeritrina/química , Controle de Qualidade
5.
Acta Cir Bras ; 31(7): 434-41, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27487277

RESUMO

PURPOSE: To investigate changes in the serum concentration and renal expression of IL-1 and TNF-α cytokines in rats that received sevoflurane and glibenclamide prior to hemorrhage. METHODS: Two groups of sevoflurane-anesthetized Wistar rats (n=10): G1 (control) and G2 (glibenclamide, 1 µg/g i.v.); hemorrhage of 30% blood volume (10% every 10 min), with replacement using Ringer solution, 5 ml/kg/h. Serum concentrations of IL-1 and TNF-α were studied in the first hemorrhage (T1) and 50 min later (T2), renal expression, at T2. RESULTS: In serum, G1 TNF-α (pg/mL) was T1=178.6±33.5, T2=509.2±118.8 (p<0.05); IL-1 (pg/mL) was T1=148.8±31.3, T2=322.6±115.4 (p<0.05); in G2, TNF-α was T1=486.2±83.6, T2=261.8±79.5 (p<0.05); IL-1 was T1=347.0±72.0, T2= 327.3±90.9 (p>0.05). The expression of TNF-α and IL-1 in the glomerular and tubular cells was significantly higher in the G2 group. CONCLUSIONS: Hemorrhage and glibenclamide elevated TNF-α and IL-1 concentrations in serum and kidneys. High levels of TNF-α already present before the hemorrhage in the glibenclamide group may have attenuated the damages found in the kidneys after the ischemia event.


Assuntos
Glibureto/farmacologia , Hipoglicemiantes/farmacologia , Interleucina-1/metabolismo , Rim/efeitos dos fármacos , Choque Hemorrágico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Anestésicos Inalatórios/administração & dosagem , Animais , Peso Corporal/efeitos dos fármacos , Canais KATP/antagonistas & inibidores , Rim/irrigação sanguínea , Rim/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Éteres Metílicos/administração & dosagem , Modelos Animais , Distribuição Aleatória , Ratos Wistar , Sevoflurano
6.
Acta cir. bras ; 31(7): 434-441, tab, graf
Artigo em Inglês | LILACS | ID: lil-787265

RESUMO

ABSTRACT PURPOSE: To investigate changes in the serum concentration and renal expression of IL-1 and TNF-α cytokines in rats that received sevoflurane and glibenclamide prior to hemorrhage. METHODS: Two groups of sevoflurane-anesthetized Wistar rats (n=10): G1 (control) and G2 (glibenclamide, 1 µg/g i.v.); hemorrhage of 30% blood volume (10% every 10 min), with replacement using Ringer solution, 5 ml/kg/h. Serum concentrations of IL-1 and TNF-α were studied in the first hemorrhage (T1) and 50 min later (T2), renal expression, at T2. RESULTS: In serum, G1 TNF-α (pg/mL) was T1=178.6±33.5, T2=509.2±118.8 (p<0.05); IL-1 (pg/mL) was T1=148.8±31.3, T2=322.6±115.4 (p<0.05); in G2, TNF-α was T1=486.2±83.6, T2=261.8±79.5 (p<0.05); IL-1 was T1=347.0±72.0, T2= 327.3±90.9 (p>0.05). The expression of TNF-α and IL-1 in the glomerular and tubular cells was significantly higher in the G2 group. CONCLUSIONS: Hemorrhage and glibenclamide elevated TNF-α and IL-1 concentrations in serum and kidneys. High levels of TNF-α already present before the hemorrhage in the glibenclamide group may have attenuated the damages found in the kidneys after the ischemia event.


Assuntos
Animais , Choque Hemorrágico/metabolismo , Interleucina-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Glibureto/farmacologia , Hipoglicemiantes/farmacologia , Rim/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Distribuição Aleatória , Ratos Wistar , Anestésicos Inalatórios/administração & dosagem , Modelos Animais , Canais KATP/antagonistas & inibidores , Rim/irrigação sanguínea , Rim/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Éteres Metílicos/administração & dosagem
7.
Parasit Vectors ; 9: 222, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27098567

RESUMO

BACKGROUND: Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Latin America. Sandfly immune responses are poorly understood. In previous work we showed that these vector insects respond to bacterial infections by modulating a defensin gene expression and activate the Imd pathway in response to Leishmania infection. Aspects of innate immune pathways in insects (including mosquito vectors of human diseases) have been revealed by studying insect cell lines, and we have previously demonstrated antiviral responses in the L. longipalpis embryonic cell line LL5. METHODS: The expression patterns of antimicrobial peptides (AMPs) and transcription factors were evaluated after silencing the repressors of the Toll pathway (cactus) and Imd pathway (caspar). AMPs and transcription factor expression patterns were also evaluated after challenge with heat-killed bacteria, heat-killed yeast, or live Leishmania. RESULTS: These studies showed that LL5 cells have active Toll and Imd pathways, since they displayed an increased expression of AMP genes following silencing of the repressors cactus and caspar, respectively. These pathways were also activated by challenges with bacteria, yeast and Leishmania infantum chagasi. CONCLUSIONS: We demonstrated that L. longipalpis LL5 embryonic cells respond to immune stimuli and are therefore a good model to study the immunological pathways of this important vector of leishmaniasis.


Assuntos
Bactérias/imunologia , Proteínas de Insetos/imunologia , Insetos Vetores/imunologia , Leishmania infantum/imunologia , Psychodidae/imunologia , Receptores Toll-Like/imunologia , Leveduras/imunologia , Animais , Linhagem Celular , Humanos , Proteínas de Insetos/genética , Insetos Vetores/embriologia , Insetos Vetores/microbiologia , Insetos Vetores/parasitologia , Leishmania infantum/fisiologia , Leishmaniose Visceral , Psychodidae/embriologia , Psychodidae/microbiologia , Psychodidae/parasitologia , Receptores Toll-Like/genética , Leveduras/fisiologia
8.
Clin Vaccine Immunol ; 18(5): 802-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21346054

RESUMO

Hepatitis C virus (HCV) infection is a major burden to public health worldwide, affecting approximately 3% of the human population. Although HCV detection is currently based on reliable tests, the field of medical diagnostics has a growing need for inexpensive, accurate, and quick high-throughput assays. By using the recombinant HCV antigens NS3, NS4, NS5, and Combined, we describe a new bead-based multiplex test capable of detecting HCV infection in human serum samples. The first analysis, made in a singleplex format, showed that each antigen coupled to an individual bead set presented high-level responses for anti-HCV-positive reference serum pools and lower-level responses for the HCV-negative pools. Our next approach was to determine the sensitivity and specificity of each antigen by testing 93 HCV-positive and 93 HCV-negative sera. When assayed in the singleplex format, the NS3, NS4, and NS5 antigens presented lower sensitivity values (50.5%, 51.6%, and 55.9%, respectively) than did the Combined antigen, which presented a sensitivity of 93.5%. All antigens presented 100% specificity. These antigens were then multiplexed in a 4-plex assay, which resulted in increased sensitivity and specificity values, performing with 100% sensitivity and 100% specificity. The positive and negative predictive values for the 4-plex assay were 100%. Although preliminary, this 4-plex assay showed robust results that, aligned with its small-sample-volume requirements and also its cost- and time-effectiveness, make it a reasonable alternative to tests currently used for HCV screening of potentially infected individuals.


Assuntos
Técnicas de Laboratório Clínico/métodos , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , Virologia/métodos , Antígenos Virais , Hepatite C/virologia , Humanos , Microesferas , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Soro/imunologia
9.
Mem Inst Oswaldo Cruz ; 104 Suppl 1: 136-41, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19753468

RESUMO

A new multiplex assay platform was evaluated to detect Trypanosoma cruzi infection using the recombinant antigens CRA, FRA, CRAFRA fusion and parasite lysate. The antigens presented different sensitivity and specificity in a singleplex test when compared to a serial dilution of two pools comprising 10 positive serum samples and one pool of 10 negative samples. The recombinant protein CRA presented lower sensitivity (55%) in contrast to the 100% specificity and sensitivity of FRA, CRAFRA and T. cruzi lysate. These antigens also showed good results in a duplex test and the duplex test with CRAFRA/T. cruzi lysate showed better performance with 100% specificity and sensitivity, as well as a lower cut-off value in comparison to the other duplex test, FRA/T. cruzi lysate. Hence, when the antigens were used in duplex format, both tests showed decreased cut-off values and no interference between different bead sets, resulting in increasing sensitivity and specificity. The results of these multiplex tests show that they could be an alternative to singleplex detection for Chagas disease, and also indicate the necessity of using multiplex diagnostic tools to increase the sensitivity and specificity for diagnostic tests. Emerging data from the T. cruzi genome and from its ORFeome project will also allow the identification of new antigens for this disease detection application.


Assuntos
Antígenos de Protozoários , Doença de Chagas/diagnóstico , Imunoensaio/métodos , Estudos de Casos e Controles , Humanos , Microesferas , Proteínas Recombinantes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Mem. Inst. Oswaldo Cruz ; 104(supl.1): 136-141, July 2009. graf
Artigo em Inglês | LILACS | ID: lil-520900

RESUMO

A new multiplex assay platform was evaluated to detect Trypanosoma cruzi infection using the recombinant antigensCRA, FRA, CRAFRA fusion and parasite lysate. The antigens presented different sensitivity and specificity in a singleplex test when compared to a serial dilution of two pools comprising 10 positive serum samples and one pool of 10 negative samples. The recombinant protein CRA presented lower sensitivity (55%) in contrast to the 100% specificity and sensitivity of FRA, CRAFRA and T. cruzi lysate. These antigens also showed good results in a duplex test and the duplex test with CRAFRA/T. cruzi lysate showed better performance with 100% specificity and sensitivity, as well as a lower cut-off value in comparison to the other duplex test, FRA/T. cruzi lysate. Hence, when the antigens were used in duplex format, both tests showed decreased cut-off values and no interference between different bead sets, resulting in increasing sensitivity and specificity. The results of these multiplex tests show that they could be an alternative to singleplex detection for Chagas disease, and also indicate the necessity of using multiplex diagnostic tools to increase the sensitivity and specificity for diagnostic tests. Emerging data from the T. cruzi genome and from its ORFeome project will also allow the identification of new antigens for this disease detection application.


Assuntos
Humanos , Antígenos de Protozoários , Doença de Chagas/diagnóstico , Imunoensaio/métodos , Estudos de Casos e Controles , Microesferas , Reprodutibilidade dos Testes , Proteínas Recombinantes , Sensibilidade e Especificidade
11.
Cien Saude Colet ; 13(4): 1153-63, 2008.
Artigo em Português | MEDLINE | ID: mdl-18813614

RESUMO

This article is based on previous studies using triangulation of methods for investigating if violence is obstructing the rights of the elderly. A questionnaire with open and closed questions was applied to a convenience sample of 72 elderly (60 or more years of age) of both sexes. Twenty-two key-informants (elderly people, community leaders and representatives of public institutions) were interviewed. In this survey we investigate the net for protection to the elderly of the city of Rio de Janeiro (institutions, assistance flow, integration, denunciations and measures taken). We analyzed 763 records of occurrences of the Police Department for the Aged and 135 of the NEAPI (Nucleus for Special Assistance for the Aged), taken care of in 2004. We emphasize domestic violence committed by close relatives and point to the need of structuring the formal net through increasing the number of institutions for protection to the aged, professional qualification, communication and integration among the agencies composing the net. We also consider important stimulating the informal nets for support and protection to the elderly.


Assuntos
Geriatria , Apoio Social , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Violência/prevenção & controle
12.
Ciênc. Saúde Colet. (Impr.) ; 13(4): 1153-1163, jul.-ago. 2008. tab
Artigo em Português | LILACS | ID: lil-488816

RESUMO

Partimos de pesquisa anterior que triangulou métodos ao investigar se a violência impede a garantia dos direitos dos idosos. A uma amostra de conveniência de 72 idosos (60 ou mais anos), de ambos os sexos, aplicamos um questionário com questões abertas e fechadas e entrevistamos 22 informantes-chave (idosos, líderes comunitários e representantes de órgãos públicos). Neste recorte, investigamos a rede de proteção ao idoso do município do Rio de Janeiro (instituições, fluxo do atendimento, articulação, denúncias que chegam e medidas tomadas). Analisamos 763 registros de ocorrências da Delegacia do Idoso e 135 do NEAPI, atendidas em 2004. Destacamos a violência doméstica perpetrada por parentes próximos. Apontamos a necessidade de estruturação da rede formal com aumento do número de instituições de proteção ao idoso, capacitação profissional, comunicação e articulação entre os órgãos que a compõem. Julgamos importante estimular as redes informais de apoio e proteção aos idosos.


This article is based on previous studies using triangulation of methods for investigating if violence is obstructing the rights of the elderly. A questionnaire with open and closed questions was applied to a convenience sample of 72 elderly (60 or more years of age) of both sexes. Twenty-two key-informants (elderly people, community leaders and representatives of public institutions) were interviewed. In this survey we investigate the net for protection to the elderly of the city of Rio de Janeiro (institutions, assistance flow, integration, denunciations and measures taken). We analyzed 763 records of occurrences of the Police Department for the Aged and 135 of the NEAPI (Nucleus for Special Assistance for the Aged), taken care of in 2004. We emphasize domestic violence committed by close relatives and point to the need of structuring the formal net through increasing the number of institutions for protection to the aged, professional qualification, communication and integration among the agencies composing the net. We also consider important stimulating the informal nets for support and protection to the elderly.


Assuntos
Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Geriatria , Apoio Social , Brasil , Violência/prevenção & controle
13.
Oral Oncol ; 44(2): 200-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17418613

RESUMO

This study evaluates the influence of genetic polymorphisms at GSTM1, GSTT1 and GSTP1 gene loci on oral cancer susceptibility among Brazilians from Rio de Janeiro. DNA extracted from white blood cells of 231 oral cancer patients and 212 hospital controls was analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. GSTM1 polymorphism distribution was different between cases and controls (P=0.006), with an overrepresentation of GSTM1 A/B genotype in controls. GSTM1 A/B individuals were at decreased oral cancer risk (OR=0.08; 95% CI=0.05-0.62). No statistically significant association was observed for GSTT1 and GSTP1 polymorphisms. Differences in the GSTM1 and GSTT1 null genotype frequencies were observed between individuals of European origin and African origin, but these genotypes do not seem to influence the risk of oral cancer. Therefore, these results do not support the hypothesis of increased risk of GSTP1 G/G, GSTM1 or GSTT1 null genotypes for developing cancer in oral cavity, but the GSTM1 A/B genotype emerged as a protective factor.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Glutationa Transferase/genética , Neoplasias Bucais/enzimologia , Polimorfismo Genético , Adulto , Idoso , Brasil , Carcinoma de Células Escamosas/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Isoenzimas/genética , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Neoplasias Bucais/genética
14.
Ren Fail ; 29(8): 1039-45, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18067053

RESUMO

INTRODUCTION: Hypovolemia from hemorrhage evokes protective compensatory reactions, such as the renin-angiotensin system, which interferes in the clearance function and can lead to ischemia. This study was designed to evaluate the effects of glibenclamide, a K(+)(ATP) channel blocker, on renal function and histology in rats in a state of hemorrhagic shock under sevoflurane anesthesia. MATERIAL AND METHODS: Twenty Wistar rats were randomized into two groups of 10 animals each (G1 and G2), only one of which (G2) received intravenous glibenclamide (1 microg.g(-1)), 60 min before bleeding was begun. Both groups were anesthetized with sevoflurane and kept on spontaneous respiration with oxygen-air, while being bled of 30% of volemia in three stages with 10 min intervals. There was an evaluation of renal function - sodium para-aminohippurate and iothalamate clearances, filtration fraction, renal blood flow, renal vascular resistance - and renal histology. Renal function attributes were evaluated at three moments: M1 and M2, coinciding with the first and third stages of bleeding; and M3, 30 min after M2, when the animals were subjected to bilateral nephrectomy before being sacrificed. RESULTS: Significant differences were found in para-aminohippurate clearance, G1 < G2, and higher renal vascular resistance values were observed in G1. Histological examination showed the greater vulnerability of kidneys exposed to sevoflurane alone (G1) with higher scores of vascular and tubular dilatation. There were vascular congestion and tubular vacuolization only in G1. Necrosis and signs of tubular regeneration did not differ in both groups. CONCLUSION: Treatment with glibenclamide attenuated acutely the renal histological changes after hemorrhage in rats under sevoflurane anesthesia.


Assuntos
Anestésicos Inalatórios/farmacologia , Glibureto/uso terapêutico , Hipoglicemiantes/uso terapêutico , Rim/efeitos dos fármacos , Éteres Metílicos/farmacologia , Choque Hemorrágico/tratamento farmacológico , Animais , Genótipo , Rim/patologia , Testes de Função Renal , Ratos , Ratos Wistar , Sevoflurano , Choque Hemorrágico/patologia
15.
Genet. mol. biol ; 30(1): 1-5, 2007. tab
Artigo em Inglês | LILACS | ID: lil-445674

RESUMO

The enzymes encoded by the polymorphic genes CYP1A1 and CYP2E1 play an important role in the activation and inactivation of xenobiotics. These enzymes have been associated with xenobiotic-induced diseases, such as cancer, therapeutic failure and adverse effects of drugs. The aim of the present study was to determine the allelic and genotypic frequencies of these polymorphisms in a large, ethnically mixed Brazilian population sample from Rio de Janeiro. Polymorphisms CYP1A1 and CYP2E1 were determined in 870 unrelated individuals by PCR-RFLP analysis in peripheral blood DNA. The observed allelic frequencies were 0.90 for CYP1A1*1A and 0.95 for CYP2E1*1A, in the total sample. The allelic frequency of CYP1A1*2C in "pardos" (0.13) and Brazilian whites (0.11) was higher than in Caucasians (0.05), which may be a result of the Amerindian genetic component, that presents the highest frequency of this allele observed up to now. The genotype distributions for both polymorphisms were in Hardy-Weinberg equilibrium and were statistically different between males and females, and among ethnic groups.


Assuntos
Humanos , Masculino , Feminino , Citocromo P-450 CYP1A1 , Citocromo P-450 CYP2E1 , Citocromos a1 , Esteroide 17-alfa-Hidroxilase
16.
Rev. bras. anestesiol ; 56(4): 343-351, set.-ago. 2006. tab
Artigo em Português | LILACS | ID: lil-432386

RESUMO

JUSTIFICATIVA E OBJETIVOS: Existem controvérsias quanto à possibilidade de a analgesia de parto interferir no andamento do trabalho de parto e na vitalidade do recém-nascido. O objetivo deste estudo foi a interação entre analgesia do parto pelas técnicas peridural contínua e duplo bloqueio, com pequena dose de anestésico local, e o tipo de parto ocorrido, pela análise do peso e índice de Apgar do recém-nascido. MÉTODO: Analisaram-se, prospectivamente, os resultados de 168 analgesias de parto (janeiro de 2002 a janeiro de 2003), divididas em quatro grupos: G1 (n = 58) peridural contínua e evolução para parto vaginal; G2 (n = 69) duplo bloqueio e evolução para parto vaginal; G3 (n = 25) peridural contínua e evolução para cesariana; G4 (n = 16) duplo bloqueio e evolução para cesariana. Para G1 foi administrada ropivacaína a 0,125 por cento (12 a 15 mL), para G2, bupivacaína a 0,5 por cento (0,5 a 1 mL), sufentanil (10 mg), por via subaracnóidea. Administrou-se ropivacaína a 0,5 por cento, por via peridural, para o parto vaginal (8 mL) e para cesariana (20 mL). Avaliaram-se idade, peso, altura, índice de massa corpórea (IMC), idade gestacional (IG), paridade e complicações (hipotensão arterial, bradicardia e hipóxia), e, do recém-nascido, peso e índice de Apgar (1°, 5° e 10° min). RESULTADOS: A maioria das parturientes era primigesta, com gestação de termo (uma IG de 28 semanas e nenhum pós-datismo), com peso, G2 < G4, e, IMC, G2 £ G4. Para o peso do RN, G1 < G3 e G2 < G4, e o Apgar do 1° min, G1 > G3. CONCLUSÕES: As técnicas de analgesia, peridural contínua e duplo bloqueio, com pequenas doses de anestésico local, não apresentaram interação com o resultado do parto, se a análise estiver focalizada no peso e no índice de Apgar do recém-nascido.


Assuntos
Feminino , Gravidez , Recém-Nascido , Humanos , Analgesia Epidural , Analgesia Obstétrica , Anestésicos Locais , Índice de Apgar , Parto Obstétrico , Recém-Nascido , Gravidez , Trabalho de Parto
17.
Oral Oncol ; 42(6): 632-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16488179

RESUMO

Xenobiotic metabolizing enzymes are involved in the detoxification of many carcinogens and may be important in modulating cancer susceptibility. CYP1A1, CYP2E1, GSTM3, and NAT2 polymorphisms were determined in peripheral blood DNA of 231 oral cancer patients and 212 hospital controls in Rio de Janeiro, Brazil, using the PCR-RFLP technique. NAT2 polymorphism distribution was different between cases and controls (P=0.035), with an overrepresentation of NAT2( *)11 mutant allele in controls. Risk analysis showed that NAT2 4/4 individuals (OR=1.95, 95% CI=1.05-3.60) and combined GSTM3 and NAT2 heterozygotes (OR=1.94, 95% CI=1.04-3.66) were at increased oral cancer risk. No statistically significant association was observed for CYP1A1 and CYP2E1 polymorphisms. Our results suggest that NAT2 polymorphism, alone or combined with GSTM3, may modulate susceptibility to oral cancer in Rio de Janeiro.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Arilamina N-Acetiltransferase/genética , Glutationa Transferase/genética , Neoplasias Bucais/genética , Polimorfismo Genético , Adolescente , Adulto , Idoso , Brasil , Estudos de Casos e Controles , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP2E1/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/enzimologia , Medição de Risco
18.
Rev Bras Anestesiol ; 56(4): 343-51, 2006 Aug.
Artigo em Português | MEDLINE | ID: mdl-19468579

RESUMO

BACKGROUND AND OBJECTIVES: There are controversies regarding whether labor analgesia can interfere with labor and the vitality of the newborn. The objective of this study was the interaction between labor analgesia, using the continuous epidural and combined spinal-epidural techniques with a small dose of local anesthetic, and the type of delivery analyzing the newborn's weight and Apgar score. METHODS: The results of 168 labor analgesias (from January 2002 to January 2003) were analyzed. They were divided in 4 groups: G1 (n = 58), continuous epidural and evolution to vaginal delivery; G2 (n = 69), combined spinal-epidural and evolution to vaginal delivery; G3 (n = 25), continuous epidural and evolution to cesarean; G4 (n = 16), combined spinal-epidural and evolution to cesarean. G1 received 0.125% ropivacaine (12 to 15 mL), G2 received subarachnoid 0.5% bupivacaine (0.5 to 1 mL) and sufentanil (10 mg). Epidural ropivacaine 0.5% for the vaginal delivery (8 mL) and for cesarean (20 mL). The patient's age, weight, height, body mass index (BMI), gestational age, number of prior pregnancies, and complications (arterial hypotension, bradycardia, and hypoxia) and the newborn's weight and Apgar score (at 1, 5, and 10 minutes) were evaluated. RESULTS: The majority of pregnant women were primiparous and presented with a term pregnancy (one with gestational age of 28 weeks and none post-term pregnancy); weight, G2 < G4; and MBI, G2 pound G4. For the weight of the newborn, G1 < G3 and G2 < G4, and for the Apgar score at 1st minute, G1 > G3. CONCLUSIONS: If the analysis focuses the newborn's weight and Apgar score, the techniques of analgesia, continuous epidural and combined spinal-epidural with small doses of local anesthetic, do not interfere with the result of the delivery.

19.
Rio de Janeiro; s.n; set. 2005. 83 p. ilus, tab.
Tese em Português | LILACS | ID: lil-442787

RESUMO

Lutzomyia longipalpis é o principal vetor de leishmaniose visceral no Brasil. A perspectiva de controlar doenças transmitidas por insetos depende de nossa capacidade em controlar o inseto vetor ou intervir na interação parasito-vetor. Enquanto isto tem sido bem estudado em malária, com o desenvolvimento de mosquitos transgênicos incapazes de transmitir o parasito, muito pouco se conhece entre a interação leishmania-flebotomíneo. Estamos estudando moléculas potencialmente envolvidas na alimentação sanguínea e infecção de L. longipalpis por L. chagasi. Através de DDRT-PCR e sequenciamento de ESTs, previamente identificamos vários genes de interesse, inclusive alguns genes potencialmente envolvidos na resposta imune inata do inseto. Um gene de TGF-? de L. longipalpis foi identificado em cDNA de flebotomíneo alimentado com sangue contendo L. chagasi, indicando um potencial papel desta molécula na resposta imune inata neste vetor. O cDNA de TGF-? de L. longipalpis foi completamente seqüenciado. Este gene contém 7 cisteínas que são conservadas entre os membros da super-família TGF-? e o domínio catalítico típico RXXR. Uma porção conservada de TGF-? de L. longipalpis foi comparada com seqüências análogas de outros membros da família. Membros individuais da super-família foram agrupados com genes ortólogos de insetos, mamíferos, aves, anfíbios e peixes. A presente seqüência parece estar mais relacionada à família das ativinas/inibinas, para as quais foi descrito um possível papel no controle de hormônio folículo estimulante, no desenvolvimento e crescimento. A ativina de L. longipalpis parece estar mais relacionada com a ativina de alguns vertebrados do que com a de D. melanogaster. Entretanto, a possibilidade de haver outras ativinas em L. longipalpis mais parecidas com a de Drosophila não pode ser descartada. Um fragmento do gene foi clonado num vetor de expressão e a proteína recombinante foi utilizada para a produção de anticorpo policlonal. A expressão...


Assuntos
Insetos Vetores , Leishmania , Psychodidae , Fator de Crescimento Transformador beta
20.
Hum Biol ; 76(6): 937-42, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15974302

RESUMO

The GSTM1 and GSTT1 null genotype frequencies were significantly different between 658 nonblack and black healthy blood donors from a Brazilian mixed population (Rio de Janeiro). The GSTM1 phenotype distribution was not in Hardy-Weinberg equilibrium in either group, mainly because of an excess of the GSTM1*A/*B genotype.


Assuntos
População Negra/genética , Frequência do Gene , Genética Populacional , Glutationa Transferase/genética , Polimorfismo Genético , População Branca/genética , Adolescente , Adulto , Alelos , Brasil , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo
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