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1.
Neurotoxicol Teratol ; 88: 107030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506931

RESUMO

Neurogenesis is a process that occurs throughout the life of a vertebrate. Among the different factors that may affect the natural occurrence of neurogenesis, obesity seems to decrease the proliferation capacity of progenitor neuronal cells. Conversely, the phytoestrogen genistein is known to attenuate some obesity effects beyond its neuroprotective action. Aiming to improve the understanding of how obesity and genistein trigger an impact on the neural and retinal progenitor competence of adult zebrafish, fish were exposed to genistein (GEN - 2 µg L-1) alone or combined with two dietary groups (control and overfeed - OFD) for up to 9 weeks. Zebrafish were fed once per day with Artemia sp. in the control and GEN (2% of BW, control diet), and three times per day in the OFD and OFD + GEN groups (12% BW, overfeeding diet). To assess obesity induction, BMI, biometric parameters, and PPAR-γ protein were quantified. Afterwards, qRT-PCR and immunohistochemistry were performed to determine the cell proliferation and the presence of stem cells through PCNA and Sox-2. Our findings proved that overfeeding adult zebrafish increased the general growth and induced the development of fatty liver. However, for OFD + GEN, this effect was assuaged through the anti-adipogenic effect of GEN. This finding suggests that phytoestrogens could be beneficial to reduce the negative effects of obesity. Moreover, OF induced negative effects on retinal and brain homeostasis, decreasing the proliferation capacity of progenitor neuronal cells. With regard to retinal progenitor competence, genistein seems to mitigate the negative impacts of obesity, whereas the effects of obesity on the brain were exacerbated by this phytoestrogen which negatively influenced the homeostasis of zebrafish neural progenitor competence. This study highlighted the fact that the effects of phytoestrogens in adult neural progenitor competence are complex and could exhibit dissimilar effects depending on the tissue.


Assuntos
Dieta/efeitos adversos , Genisteína/farmacologia , Células-Tronco/citologia , Fatores de Tempo , Animais , Dietoterapia/efeitos adversos , Dietoterapia/métodos , Obesidade/fisiopatologia , Fitoestrógenos/farmacologia , Peixe-Zebra
2.
Environ Toxicol Pharmacol ; 86: 103674, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34029728

RESUMO

Copper (Cu) is an essential element for organism's metabolism, being controversially listed as a priority pollutant. Importantly, the toxicity of Cu has been linked to several cell death pathways. Thus, this study aimed to assess if macroautophagic pathways are triggered by Cu in zebrafish gill, the main target of waterborne pollutants. The electron microscopy findings indicated that Cu induced profound impacts on zebrafish gill structure and functions, being this tissue a biomarker sensitive enough to indicate early toxic effects. The findings also support a clear impairment of autophagy, througth the absence of phagossomes and the significant down-regulation mRNA transcript levels of microtubule-associated protein light chain 3 (LC3). The reduction of LC3 levels was often associated to an increase of apoptotic activation, indicating that the inhibition of macroautophagy triggers apoptosis in zebrafish gills. This study highlighted that the autophagic down-regulation might be affected through the activation of other cell death signaling pathway.


Assuntos
Autofagia/efeitos dos fármacos , Cobre/toxicidade , Epitélio/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Epitélio/anatomia & histologia , Epitélio/metabolismo , Epitélio/ultraestrutura , Brânquias/anatomia & histologia , Brânquias/metabolismo , Brânquias/ultraestrutura , Proteínas Associadas aos Microtúbulos/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
3.
Arq Bras Cardiol ; 114(3): 530-537, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32267326

RESUMO

BACKGROUD: The prevalence of obesity has systematically been increased in the population, including children and adolescents, around the world. OBJECTIVES: To describe reference percentile curves for waist circumference (WC) in Brazilian children and provide cut-off values of WC to identify children at risk for obesity. METHODS: A multicenter, prospective, cross-sectional study was performed with children aged from 6 to 10 years old, enrolled in public and private elementary schools from 13 cities of the São Paulo State. Height, weight, and WC were measured in duplicate in 22,000 children (11,199 boys). To establish the WC best cut-off value for obesity diagnosis, ROC curves with children classified as normal weight and obese were calculated, according to BMI curves, stratified by gender and age, and the Youden Index was utilized as the maximum potential effectiveness of this biomarker. A p < 0.05 was considered statistically significant. RESULTS: WC values increased with age in both boys and girls. The prevalence of obesity in each age group varied from 17% (6 years old) to 21.6% (9 years old) among boys, and from 14.1% (7 years old) to 17.3 % (9 years old) among girls. ROC analyses have shown the 75th percentile as a cut-off for obesity risk, and the diagnosis of obesity is classified on the 85th percentile or more. CONCLUSION: Age and gender specific reference curves of WC for Brazilian children and cut-off values for obesity risk may be used for national screening and interventional studies to reduce the obesity burden in Brazil. (Arq Bras Cardiol. 2020; 114(3):530-537).


FUNDAMENTO: A prevalência da obesidade vem aumentando sistematicamente na população, inclusive nas crianças e adolescentes, ao redor do mundo. OBJETIVOS: Descrever curvas percentílicas de referência para a circunferência abdominal (CA) nas crianças brasileiras e fornecer pontos de corte da CA para identificar crianças com risco de obesidade. MÉTODOS: Um estudo multicêntrico, prospectivo, tranversal foi realizado em crianças com idades entre 6 e 10 anos, matriculadas no ensino fundamental de escolas públicas e particulares de 13 cidades do estado de São Paulo. A estatura, o peso e a CA foram medidos em duplicata em 22.000 crianças (11.199 meninos). Para estabelecer o melhor ponto de corte da CA para o diagnóstico da obesidade, foram calculadas curvas ROC com crianças classificadas como com peso normal e obesas, de acordo com as curvas do IMC, estratificadas por gênero e idade, e o índice Youden foi utilizado como a eficácia potencial máxima desse biomarcador. Valores de p < 0,05 foram considerados estatisticamente significativos. RESULTADOS: Os valores da CA aumentaram com a idade, tanto nos meninos quanto nas meninas. A prevalência de obesidade em cada grupo variou de 17% (6 anos de idade) a 21,6 % (9 anos de idade), dentre os meninos, e de 14,1% (7 anos de idade) a 17,3 % (9 anos de idade), dentre as meninas. As análises ROC mostraram o percentil 75 como ponto de corte para o risco de obesidade, e o diagnóstico de obesidade está classificado no percentil 85 ou acima. CONCLUSÃO: Curvas de referência da CA específicas para idade e sexo em crianças brasileiras e pontos de corte para o risco de obesidade podem ser usados em triagem nacional e estudos intervencionais para reduzir a carga da obesidade no Brasil. (Arq Bras Cardiol. 2020; 114(3):530-537).


Assuntos
Obesidade , Estudantes , Índice de Massa Corporal , Brasil , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos , Valores de Referência , Circunferência da Cintura
4.
Arq. bras. cardiol ; 114(3): 530-537, mar. 2020. tab, graf
Artigo em Português | LILACS, Sec. Est. Saúde SP, CONASS, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1088880

RESUMO

Resumo Fundamento A prevalência da obesidade vem aumentando sistematicamente na população, inclusive nas crianças e adolescentes, ao redor do mundo. Objetivos Descrever curvas percentílicas de referência para a circunferência abdominal (CA) nas crianças brasileiras e fornecer pontos de corte da CA para identificar crianças com risco de obesidade. Métodos Um estudo multicêntrico, prospectivo, tranversal foi realizado em crianças com idades entre 6 e 10 anos, matriculadas no ensino fundamental de escolas públicas e particulares de 13 cidades do estado de São Paulo. A estatura, o peso e a CA foram medidos em duplicata em 22.000 crianças (11.199 meninos). Para estabelecer o melhor ponto de corte da CA para o diagnóstico da obesidade, foram calculadas curvas ROC com crianças classificadas como com peso normal e obesas, de acordo com as curvas do IMC, estratificadas por gênero e idade, e o índice Youden foi utilizado como a eficácia potencial máxima desse biomarcador. Valores de p < 0,05 foram considerados estatisticamente significativos. Resultados Os valores da CA aumentaram com a idade, tanto nos meninos quanto nas meninas. A prevalência de obesidade em cada grupo variou de 17% (6 anos de idade) a 21,6 % (9 anos de idade), dentre os meninos, e de 14,1% (7 anos de idade) a 17,3 % (9 anos de idade), dentre as meninas. As análises ROC mostraram o percentil 75 como ponto de corte para o risco de obesidade, e o diagnóstico de obesidade está classificado no percentil 85 ou acima. Conclusão Curvas de referência da CA específicas para idade e sexo em crianças brasileiras e pontos de corte para o risco de obesidade podem ser usados em triagem nacional e estudos intervencionais para reduzir a carga da obesidade no Brasil. (Arq Bras Cardiol. 2020; 114(3):530-537)


Abstract Backgroud The prevalence of obesity has systematically been increased in the population, including children and adolescents, around the world. Objectives To describe reference percentile curves for waist circumference (WC) in Brazilian children and provide cut-off values of WC to identify children at risk for obesity. Methods A multicenter, prospective, cross-sectional study was performed with children aged from 6 to 10 years old, enrolled in public and private elementary schools from 13 cities of the São Paulo State. Height, weight, and WC were measured in duplicate in 22,000 children (11,199 boys). To establish the WC best cut-off value for obesity diagnosis, ROC curves with children classified as normal weight and obese were calculated, according to BMI curves, stratified by gender and age, and the Youden Index was utilized as the maximum potential effectiveness of this biomarker. A p < 0.05 was considered statistically significant. Results WC values increased with age in both boys and girls. The prevalence of obesity in each age group varied from 17% (6 years old) to 21.6% (9 years old) among boys, and from 14.1% (7 years old) to 17.3 % (9 years old) among girls. ROC analyses have shown the 75th percentile as a cut-off for obesity risk, and the diagnosis of obesity is classified on the 85th percentile or more. Conclusion Age and gender specific reference curves of WC for Brazilian children and cut-off values for obesity risk may be used for national screening and interventional studies to reduce the obesity burden in Brazil. (Arq Bras Cardiol. 2020; 114(3):530-537)


Assuntos
Humanos , Masculino , Feminino , Criança , Estudantes , Obesidade , Valores de Referência , Brasil , Índice de Massa Corporal , Estudos Transversais , Estudos Prospectivos , Circunferência da Cintura
5.
Saúde Soc ; 29(2): e181046, 2020. graf
Artigo em Português | LILACS | ID: biblio-1101917

RESUMO

Resumo O objetivo deste artigo é analisar a influência dos determinantes socioambientais da saúde na incidência de malária por Plasmodium vivax na fronteira franco-brasileira. O estudo foi realizado entre 2011 e 2015, no município de Oiapoque (AP), na Amazônia brasileira. Foram incluídos na amostra 253 indivíduos de ambos os sexos, de 10 a 60 anos de idade. Houve predominância de 63,64% (161/253) de casos de malária em adultos do sexo masculino. A faixa etária mais acometida foi de 20 a 29 anos, com 30% (76/253); 84,6% (214/253) dos pacientes não concluíram o ensino médio, e 29,6% (75/253) não concluíram o ensino primário. No aspecto ambiental, houve correlação negativa entre as precipitações pluviométricas e a incidência da malária por P. vivax (p=0,0026). Em termos de mobilidade, constatou-se considerável proporção de migrantes provenientes dos estados do Pará e do Maranhão (55,73%; 141/253). Por fim, os dados apontaram que 31,23% (79/253) dos casos de malária foram importados da Guiana Francesa. Em síntese, a transmissão da malária na fronteira franco-brasileira envolve fatores ecológico-ambientais, biológicos e sociais que se expressam na elevada vulnerabilidade social da população que vive e circula na zona fronteiriça, favorecendo a ocorrência de surtos e a permanência da enfermidade.


Abstract This study analyzes the influence of socio-environmental health determinants on the maintenance of Plasmodium vivax malaria at the borders between French Guiana and Brazil. This study was carried out between 2011 and 2015 in the city of Oiapoque, Amapá, situated in the Brazilian Amazon region. The sample included 253 individuals of both sexes aged between 10 and 60 years. The disease was predominant in 63.64% (161/253) adult males. The most affected age group was 20 to 29 years old, with 30% (76/253). About 84.6% did not complete high school, while 29.6% (75/253) of the cases had not finished the first degree. Concerning the environmental aspect, negative correlation was observed between rainfall and the incidence of P. vivax malaria (p=0.0026). In terms of mobility, there was a considerable influx of migrants from the states of Pará and Maranhão, with 55.73% (141/253). Lastly, the data indicated that 31.23% (79/253) of malaria cases were imported from French Guiana. In summary, the transmission of malaria in these particular borders involved ecological, environmental, biological and social factors, which are expressed in the high social vulnerability of the population living and circulating in the border zone, favoring the occurrence of outbreaks and the maintenance of the disease.


Assuntos
Humanos , Masculino , Feminino , Impactos da Poluição na Saúde/análise , Saúde na Fronteira , Meio Ambiente , Migração Humana , Determinantes Sociais da Saúde , Malária/transmissão , Malária Vivax
6.
Malar J ; 14: 402, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26453152

RESUMO

BACKGROUND: Plasmodium vivax malaria is an important public health issue in the Amazon region, and it accounts for approximately 84 % of cases of the disease. Migration across the border between Brazil and French Guiana contributes to the maintenance of the disease. The aim of this study was to evaluate the therapeutic and parasitological responses of patients with P. vivax malaria treated with chloroquine and primaquine in the socio-environmental context of cross-border interactions between Brazil and French Guiana. The factors controlled were diagnostic agreement, adherence, adjustment of primaquine doses for patient weight, and quality of the drugs used. METHODS: A prospective study was conducted in 2011 with 103 individuals aged 10-60 years with a positive diagnosis of P. vivax treated with chloroquine (10 mg base/kg on the first day, followed by 7.5 mg/kg on the second and third days) and primaquine for 7 days, who were followed for 28 days. The primaquine doses were adjusted for the patients' weight. A number of factors were determined: epidemiological characteristics, origin of patients, signs and symptoms, initial parasitaemia and parasitaemia clearance time, blood concentrations of chloroquine and primaquine, quality of anti-malarial drugs and diagnostic agreement. RESULTS: Ninety-five patients were followed for 28 days. There was a 100 % agreement in microscopic diagnosis between field laboratory and reference centre. The adhesion to the treatment was 100 %. Of these patients, 32.6 % received a weight-adjusted dose of primaquine. The chloroquine and primaquine tablets were consistent with the optimal quality limits for human consumption. The investigated patients achieved optimal blood exposure to anti-malarial drugs. The parasitological and therapeutic response was adequate in 99.0 % of cases. CONCLUSIONS: In the municipality of Oiapoque, the therapeutic regime used for the treatment of P. vivax malaria using chloroquine combined with primaquine remains effective, when external factors are controlled, such as the quality of anti-malarial drugs, the adhesion to the treatment prescribed, the correct diagnostic and the adjustment of primaquine dose for patient body weight.


Assuntos
Antimaláricos/administração & dosagem , Malária Vivax/tratamento farmacológico , Adolescente , Adulto , Brasil/epidemiologia , Criança , Cloroquina/administração & dosagem , Quimioterapia Combinada/métodos , Feminino , Guiana Francesa , Migração Humana , Humanos , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Primaquina/administração & dosagem , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
7.
Cell Death Dis ; 4: e636, 2013 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-23681231

RESUMO

It has been claimed that glutamate excitotoxicity might have a role in the pathogenesis of several retinal degenerative diseases, including glaucoma and diabetic retinopathy. Neuropeptide Y (NPY) has neuroprotective properties against excitotoxicity in the hippocampus, through the activation of Y1, Y2 and/or Y5 receptors. The principal objective of this study is to investigate the potential protective role of NPY against glutamate-induced toxicity in rat retinal cells (in vitro and in an animal model), unraveling the NPY receptors and intracellular mechanisms involved. Rat retinal neural cell cultures were prepared from newborn Wistar rats (P3-P5) and exposed to glutamate (500 µM) for 24 h. Necrotic cell death was evaluated by propidium iodide (PI) assay and apoptotic cell death using TUNEL and caspase-3 assays. The cell types present in culture were identified by immunocytochemistry. The involvement of NPY receptors was assessed using selective agonists and antagonists. Pre-treatment of cells with NPY (100 nM) inhibited both necrotic cell death (PI-positive cells) and apoptotic cell death (TUNEL-positive cells and caspase 3-positive cells) triggered by glutamate, with the neurons being the cells most strongly affected. The activation of NPY Y2, Y4 and Y5 receptors inhibited necrotic cell death, while apoptotic cell death was only prevented by the activation of NPY Y5 receptor. Moreover, NPY neuroprotective effect was mediated by the activation of PKA and p38K. In the animal model, NPY (2.35 nmol) was intravitreally injected 2 h before glutamate (500 nmol) injection into the vitreous. The protective role of NPY was assessed 24 h after glutamate (or saline) injection by TUNEL assay and Brn3a (marker of ganglion cells) immunohistochemistry. NPY inhibited the increase in the number of TUNEL-positive cells and the decrease in the number of Brn3a-positive cells induced by glutamate. In conclusion, NPY and NPY receptors can be considered potential targets to treat retinal degenerative diseases, such as glaucoma and diabetic retinopathy.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Necrose , Neurônios/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Animais , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Masculino , Neurônios/citologia , Neuropeptídeo Y/farmacologia , Ratos , Ratos Wistar , Receptores de Neuropeptídeo Y/agonistas , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Retina/citologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Trans R Soc Trop Med Hyg ; 107(6): 377-83, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23604864

RESUMO

BACKGROUND: Plasmodium vivax is the most prevalent malaria species in Brazil. The parasite-host coevolutionary process can be viewed as an 'arms race', in which adaptive genetic changes in one are eventually matched by alterations in the other. METHODS: Following the candidate gene approach we analyzed the CD40, CD40L and BLYS genes that participate in B-cell co-stimulation, for associations with P. vivax malaria. The study sample included 97 patients and 103 controls. We extracted DNA using the extraction and purification commercial kit and identified the following SNPs: -1C > T in the CD40 gene, -726T > C in the CD40L gene and the -871C > T in the BLyS gene using PCR-RFLP. We analyzed the genotype and allele frequencies by direct counting. We also compared the observed with the expected genotype frequencies using the Hardy-Weinberg equilibrium. RESULTS: The allele and genotype frequencies for these SNPs did not differ statistically between patient and control groups. Gene-gene interactions were not observed between the CD40 and BLYS and between the CD40L and BLYS genes. Overall, the genes were in Hardy-Weinberg equilibrium. Significant differences were not observed among the frequencies of antibody responses against P. vivax sporozoite and erythrocytic antigens and the CD40 and BLYS genotypes. CONCLUSIONS: The results of this study show that, although the investigated CD40, CD40L and BLYS alleles differ functionally, this variation does not alter the functionality of the molecules in a way that would interfere in susceptibility to the disease. The variants of these genes may influence the clinical course rather than simply increase or decrease susceptibility.


Assuntos
Fator Ativador de Células B/genética , Antígenos CD40/genética , Ligante de CD40/genética , Malária Vivax/genética , Plasmodium vivax/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Antígenos de Protozoários/genética , Brasil , DNA de Protozoário/análise , Progressão da Doença , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Modelos Logísticos , Malária Vivax/imunologia , Masculino , Adulto Jovem
9.
J Infect Dev Ctries ; 7(3): 243-52, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23493003

RESUMO

INTRODUCTION: In remote areas of the Amazon Region, diagnosis of malaria by microscopy is practically impossible. This study aimed to evaluate the performance of two rapid diagnostic tests (RDTs) targeting different malaria antigens stored at room temperature in the Brazilian Amazon Region. METHODOLOGY: Performance of the OptiMal Pf/Pan test and ICT-Now Pf/Pan test was analyzed retrospectively in 1,627 and 1,602 blood samples, respectively. Tests were performed over a 15-month period. Kits were stored at room temperature in five community health centres located in the Brazilian Amazon Region. RDT results were compared with thick blood smear (TBS) results to determine sensitivity, specificity, and accuracy of the RDT. RESULTS: The sensitivities of the OptiMal Pf/Pan test were 79.7% for Plasmodium falciparum malaria diagnosis and 85.7% for non-P. falciparum infections. The results showed a crude agreement of 88.5% for P. falciparum, and 88.3% for non-P. falciparum infections (Kappa index = 0.74 and 0.75, respectively). For the ICT-Now Pf/Pan test (CI 95%), the sensitivities were 87.9% for P. falciparum malaria diagnosis and 72.5% for non-P. falciparum infection. Crude agreement between the ICT-Now Pf/Pan test and TBS was 91.4% for P. falciparum and 79.7% for non-P. falciparum infection. The Kappa index was 0.81 and 0.59 for the final diagnosis of P. falciparum and non-P. falciparum, respectively. Higher levels of parasitaemia were associated with higher crude agreement between RDT and TBS. CONCLUSIONS: The sensitivities of RDTs stored at room temperature over a 15-month period and performed in field conditions were lower than those previously reported.


Assuntos
Antígenos de Protozoários/sangue , Testes Diagnósticos de Rotina/métodos , Malária Falciparum/diagnóstico , Plasmodium falciparum/isolamento & purificação , Manejo de Espécimes/métodos , Adolescente , Adulto , Idoso , Brasil , Criança , Pré-Escolar , Feminino , Humanos , Imunoensaio/métodos , Lactente , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/imunologia , Sensibilidade e Especificidade , Temperatura , Fatores de Tempo , Adulto Jovem
10.
Malar J ; 9: 178, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20573199

RESUMO

BACKGROUND: Plasmodium vivax circumsporozoite variants have been identified in several geographical areas. The real implication of the genetic variation in this region of the P. vivax genome has been questioned for a long time. Although previous studies have observed significant association between VK210 and the Duffy blood group, we present here that evidences of this variation are limited to the CSP central portion. METHODS: The phylogenetic analyses were accomplished starting from the amplification of conserved domains of 18 SSU RNAr and Cyt B. The antibodies responses against the CSP peptides, MSP-1, AMA-1 and DBP were detected by ELISA, in plasma samples of individuals infected with two P. vivax CS genotypes: VK210 and P. vivax-like. RESULTS: These analyses of the two markers demonstrate high similarity among the P. vivax CS genotypes and surprisingly showed diversity equal to zero between VK210 and P. vivax-like, positioning these CS genotypes in the same clade. A high frequency IgG antibody against the N- and C-terminal regions of the P. vivax CSP was found as compared to the immune response to the R- and V- repetitive regions (p = 0.0005, Fisher's Exact test). This difference was more pronounced when the P. vivax-like variant was present in the infection (p = 0.003, Fisher's Exact test). A high frequency of antibody response against MSP-1 and AMA-1 peptides was observed for all P. vivax CS genotypes in comparison to the same frequency for DBP. CONCLUSIONS: This results target that the differences among the P. vivax CS variants are restrict to the central repeated region of the protein, mostly nucleotide variation with important serological consequences.


Assuntos
Variação Genética , Proteína 1 de Superfície de Merozoito/genética , Plasmodium vivax/genética , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Citocromos b/genética , Genótipo , Humanos , Malária Vivax/parasitologia , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteína 1 de Superfície de Merozoito/imunologia , Dados de Sequência Molecular , Filogenia , Plasmodium vivax/classificação , Reação em Cadeia da Polimerase , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA
11.
Trans R Soc Trop Med Hyg ; 103(7): 672-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18804827

RESUMO

The circumsporozoite protein (CSP) of the Plasmodium vivax infective sporozoite is considered to be a major target for the development of recombinant malaria vaccines. The Duffy blood group molecule acts as the red blood cell receptor for P. vivax. We review the frequency of P. vivax CSP variants and report their association with the Duffy blood group genotypes from Brazilian Amazon patients carrying P. vivax malaria. Peripheral blood samples were collected from 155 P. vivax-infected individuals from five Brazilian malaria-endemic areas. The P. vivax CSP variants and the Duffy blood group genotypes were assessed using PCR/RFLP. In single infections, the VK210 variant was the commonest followed by the P. vivax-like variant. The typing of P. vivax indicated that the frequency of variants among the study areas was significantly different from one to another. This is the first detection of the VK247 and P. vivax-like variant in single infections in endemic areas of Brazil. Association of the CSP P. vivax variants with the heterozygous Duffy blood group system genotype was significant for VK210 single infection. These observations provide additional data on the Plasmodium-host interactions concerning the Duffy blood group and P. vivax capability of causing human malaria.


Assuntos
Sistema do Grupo Sanguíneo Duffy/genética , Malária Vivax/sangue , Plasmodium vivax , Proteínas de Protozoários/sangue , Animais , Brasil , Feminino , Variação Genética/fisiologia , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos , Proteínas de Protozoários/classificação
12.
Neuroscience ; 152(1): 97-105, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-18249070

RESUMO

Ecstasy (3,4-methylenedioxymethamphetamine; MDMA) has potent CNS stimulant effects. Besides the acute effects of MDMA, such as psychomotor activation, euphoria, decreased appetite, and hyperthermia, long-term damage of dopaminergic and serotonergic nerve terminals in multiple brain areas have also been reported. Although some studies have demonstrated that considerable amounts of MDMA reach the vitreous humor of the eye, and that serious visual consequences can result from MDMA consumption, the toxic effect of MDMA on the retina has not been completely elucidated. Neuropeptide Y (NPY) is present in the CNS, including the retina. The aim of the present study was to evaluate the effect of MDMA on rat retinal neural cell viability and investigate the involvement of 5-HT 2A-receptor (5-HT(2A)) activation. Moreover, the neuroprotective role of NPY on MDMA-induced toxicity was also investigated. MDMA induced necrosis [MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and propidium iodide assays] and apoptosis (immunoreactivity of cleaved caspase-3) in mixed cultures of retinal neural cells (neurons, macroglia and microglia), in a concentration-dependent manner. MDMA-induced toxicity was enhanced at higher temperature (40 degrees C) and was reduced by the 5HT(2A)-receptor antagonist, ketanserin (1 microM). Interestingly, necrotic and apoptotic cell death induced by MDMA was inhibited by NPY (100 nM).


Assuntos
Morte Celular/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Neurônios/efeitos dos fármacos , Neuropeptídeo Y/metabolismo , Serotoninérgicos/toxicidade , Animais , Células Cultivadas , Temperatura Alta , Imuno-Histoquímica , Ketanserina/farmacologia , Neurônios/patologia , Ratos , Ratos Wistar , Receptor 5-HT2A de Serotonina/metabolismo , Retina/efeitos dos fármacos , Retina/patologia , Antagonistas da Serotonina/farmacologia
13.
Malar J ; 6: 167, 2007 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-18093292

RESUMO

BACKGROUND: Duffy blood group polymorphisms are important in areas where Plasmodium vivax predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in P. vivax malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria. METHODS: The P. vivax identification was determined by non-genotypic and genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP in 330 blood donors and 312 malaria patients from four Brazilian Amazon areas. In order to assess the variables significance and to obtain independence among the proportions, the Fisher's exact test was used. RESULTS: The data show a high frequency of the FYA/FYB genotype, followed by FYB/FYB, FYA/FYA, FYA/FYB-33 and FYB/FYB-33. Low frequencies were detected for the FYA/FYX, FYB/FYX, FYX/FYX and FYB-33/FYB-33 genotypes. Negative Duffy genotype (FYB-33/FYB-33) was found in both groups: individuals infected and non-infected (blood donors). No individual carried the FYX/FYB-33 genotype. Some of the Duffy genotypes frequencies showed significant differences between donors and malaria patients. CONCLUSION: The obtained data suggest that individuals with the FYA/FYB genotype have higher susceptibility to malaria. The presence of the FYB-33 allele may be a selective advantage in the population, reducing the rate of infection by P. vivax in this region. Additional efforts may contribute to better elucidate the physiopathologic differences in this parasite/host relationship in regions endemic for P. vivax malaria, in particular the Brazilian Amazon region.


Assuntos
Sistema do Grupo Sanguíneo Duffy/genética , Malária Vivax/genética , Adolescente , Adulto , Alelos , Animais , Doadores de Sangue , Brasil/epidemiologia , Feminino , Genótipo , Humanos , Malária Vivax/sangue , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Polimorfismo de Fragmento de Restrição
14.
Am J Trop Med Hyg ; 77(5): 977-83, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17984363

RESUMO

Antibody responses to malaria invasion ligands and proteins on the merozoite surface have been shown to interfere with red cell invasion and correlate with immunity to malaria. The current study is the first to characterize the antibody responses to EBA-140 and EBA-181, Plasmodium falciparum invasion ligands implicated in the alternative pathways of invasion, in age-matched populations of individuals living in endemic areas in both Brazil and Cameroon. Antibody responses to the proteins screened were different between populations. The African individuals reacted strongly with most fragments of these two EBAs, while the majority of the individuals from Mato Grosso, Brazil, reacted weakly and those from the Amazon had elevated responses to these EBA proteins. When compared with the responses against MSP-1(19) and EBA-175, it appeared that the Brazilian population has a variable ability to recognize P. falciparum invasion ligand proteins and that these responses are distinct from the African population.


Assuntos
Anticorpos Antiprotozoários/imunologia , Malária Falciparum/imunologia , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/imunologia , Adulto , Distribuição por Idade , Animais , Brasil/epidemiologia , Camarões/epidemiologia , Doenças Endêmicas , Regulação da Expressão Gênica , Humanos , Plasmodium falciparum/imunologia , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes/imunologia
15.
Am J Trop Med Hyg ; 76(3): 461-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17360868

RESUMO

Vector incrimination studies were conducted from April 2003 to February 2005 at three riverine villages 1.5 km to 7.0 km apart, along the Matapi River, Amapa State, Brazil. A total of 113,117 mosquitoes were collected and placed in pools of

Assuntos
Anopheles/parasitologia , Insetos Vetores/parasitologia , Malária/transmissão , Plasmodium/isolamento & purificação , Animais , Brasil/epidemiologia , Humanos , Incidência , Mordeduras e Picadas de Insetos , Malária/epidemiologia
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