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1.
Epidemiol Infect ; 146(9): 1184-1193, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781414

RESUMO

Persistent infection with high-risk human papillomavirus (HPV) is the main cause of cervical cancer and the prevalence of HPV types varies depending on the geographic region. Therefore, this study assessed the prevalence of HPV types in women with cervical lesions from Sergipe state, Northeastern Brazil. A cross-sectional study was conducted in women with cervical lesions from March to December 2014. These lesions were investigated by PCR and HPV types were identified by DNA sequencing. 432 patients were included, of which 337 patients tested positive for HPV. Eighteen different HPV types were detected, and high-risk HPV types were detected in 69.2%. HPV 16 (63.4%) was the most prevalent HPV type found, followed by HPV 66 (4.6%), HPV 18 (1.6%) and HPV 45 (1.4%). These results highlight the importance of the high prevalence of HPV 66, which is a possibly carcinogenic virus type not covered by the available vaccines. The prevalence of HPV 16 was high in the studied population, reaffirming the importance of young vaccination. However, the high prevalence of HPV 66 found in this study shows the importance of monitoring the diversity of HPV types in different populations and geographic regions to better understand the impacts of current HPV vaccines.


Assuntos
Alphapapillomavirus/classificação , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Alphapapillomavirus/genética , Alphapapillomavirus/isolamento & purificação , Brasil/epidemiologia , Estudos Transversais , DNA Viral/análise , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Prevalência , Medição de Risco , Fatores de Risco , Adulto Jovem
2.
Analyst ; 142(13): 2451-2459, 2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28574079

RESUMO

Proximal phosphorylation on proteins appears to have functional significance and has been associated with several diseases, including Alzheimer's and cancer. While much remains to be learned about the role of proximal phosphorylation in biological systems, no simple and/or affordable technique is available for its detection. To this end, we have previously developed a ProxyPhos chemosensor, which detects proximally phosphorylated peptides and proteins over mono- and non-phosphorylated motifs in aqueous solutions. In this follow-up work, we performed extensive characterization of peptide and protein ProxyPhos assay conditions to achieve enhanced detection, and further explored the selectivity of ProxyPhos, and its potential off-targets. As a result of characterization studies, selective sensing of proximally phosphorylated over mono-phosphorylated peptides and proteins was achieved. Moreover, studies demonstrated that ProxyPhos was compatible with the detection of all commonly phosphorylated residues (i.e. tyrosine, serine and threonine residues). Under optimized conditions, ProxyPhos efficiently discriminated between peptides derived from the activated (proximally phosphorylated, disease-relevant) and inactive (mono-phosphorylated) forms of JAK2, SYK and MAPK1 kinases. In addition, ProxyPhos can be used to probe phosphatase activity on peptides and proteins via detecting changes in proximal phosphorylation, demonstrating immediate utility of this chemosensing system.


Assuntos
Peptídeos/química , Proteínas/química , Espectrometria de Fluorescência , Corantes Fluorescentes , Fosforilação , Serina , Treonina , Tirosina
3.
Oncogene ; 36(5): 606-617, 2017 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-27775079

RESUMO

Medulloblastoma (MB), the most common malignant paediatric brain tumor, is currently treated using a combination of surgery, craniospinal radiotherapy and chemotherapy. Owing to MB stem cells (MBSCs), a subset of MB patients remains untreatable despite standard therapy. CD133 is used to identify MBSCs although its functional role in tumorigenesis has yet to be determined. In this work, we showed enrichment of CD133 in Group 3 MB is associated with increased rate of metastasis and poor clinical outcome. The signal transducers and activators of transcription-3 (STAT3) pathway are selectively activated in CD133+ MBSCs and promote tumorigenesis through regulation of c-MYC, a key genetic driver of Group 3 MB. We screened compound libraries for STAT3 inhibitors and treatment with the selected STAT3 inhibitors resulted in tumor size reduction in vivo. We propose that inhibition of STAT3 signaling in MBSCs may represent a potential therapeutic strategy to treat patients with recurrent MB.


Assuntos
Antígeno AC133/biossíntese , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Meduloblastoma/tratamento farmacológico , Meduloblastoma/patologia , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Fator de Transcrição STAT3/antagonistas & inibidores , Antígeno AC133/imunologia , Animais , Neoplasias Encefálicas/imunologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Xenoenxertos , Humanos , Masculino , Meduloblastoma/imunologia , Camundongos , Recidiva Local de Neoplasia/imunologia , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Bibliotecas de Moléculas Pequenas/farmacologia , Regulação para Cima
4.
Genet Mol Res ; 15(2)2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27173196

RESUMO

In the present study, we used morphological and behavioral analyses to assess the effects of seasonality and morphoclimatic patterns on the morphology, behavior, and distribution of 71 colonies of Africanized honey bees in 3 distinct ecoregions (Zona da Mata, Agreste, and Sertão) within the State of Sergipe, north-eastern Brazil. We found a high rate of gene flow among the studied colonies. However, there were pronounced morphological differences among localities and ecoregions, and body shape (r = 0.06239; P = 0.05) and size (P < 0.001) varied with altitude. Regional groups were separated by phenotypic plasticity, rather than genetic divergence. We also found a significant difference in the hygienic behavior of these populations between the dry and rainy seasons (P = 0.022; α = 0.05) and between ecoregions (P = 0.001; α = 0.05). The main modulator of hygienic behavior was the influence of temperature (ρ = 0.065; P = 0.471; α = 0.05) and altitude (ρ = -0.294; P = 0.001; α = 0.05) on rainfall (ρ = 0.274; P = 0.002; α = 0.05). This supports the hypothesis that environmental factors influence the expression of hygienic behavior trait. The influence of environmental factors on the morphology, behavior, and distribution of Africanized honey bees, together with the identified polyphenisms, indicate high genetic variability within these populations that can be exploited in future bee handling and breeding programs.


Assuntos
Abelhas/genética , Variação Genética , Estações do Ano , Adaptação Fisiológica , Animais , Abelhas/anatomia & histologia , Abelhas/fisiologia , Comportamento Animal , Tamanho Corporal , Fluxo Gênico , Fenótipo
5.
Braz. j. biol ; 73(4): 887-893, 1jan. 2013. map, ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468158

RESUMO

This study aimed to identify differences in wing shape among populations of Melipona quadrifasciata anthidioides obtained in 23 locations in the semi-arid region of Bahia state (Brazil). Analysis of the Procrustes distances among mean wing shapes indicated that population structure did not determine shape variation. Instead, populations were structured geographically according to wing size. The Partial Mantel Test between morphometric (shape and size) distance matrices and altitude, taking geographic distances into account, was used for a more detailed understanding of size and shape determinants. A partial Mantel test between morphometris (shape and size) variation and altitude, taking geographic distances into account, revealed that size (but not shape) is largely influenced by altitude (r = 0.54 p 0.01). These results indicate greater evolutionary constraints for the shape variation, which must be directly associated with aerodynamic issues in this structure. The size, however, indicates that the bees tend to have larger wings in populations located at higher altitudes.


Este trabalho avaliou a divergência de forma entre populações de Melipona quadrifasciata anthidioides, utilizando caracteres morfométricos em 23 localidades da região semi-árida do estado da Bahia (Brasil). As análises das distâncias de Procrustes entre as formas médias das asas indicaram que não há estruturação populacional para a variação dessa estrutura. Entretanto, nossas análises demonstraram que as populações estavam estruturadas geograficamente pelo tamanho das asas. O teste parcial de Mantel entre matrizes de distâncias morfométricas (forma e tamanho) e altitude, levando em conta as distâncias geográficas, foi utilizado para uma compreensão mais detalhada dos determinantes de tamanho e forma. O teste de Mantel entre as variações morfométricas (forma e tamanho) e altitude, tendo em conta as distâncias geográficas, revelou que o tamanho (mas não a forma) é amplamente influenciado pela altitude (r = 0,54 p 0,01). Tais resultados indicam maiores restrições evolutivas para a variação de forma, o que deve estar diretamente associado às questões aerodinâmicas dessa estrutura. O tamanho, por outro lado, indica que as abelhas estudadas tendem a apresentar asas maiores nas populações localizadas em regiões de maior altitude.


Assuntos
Animais , Abelhas/anatomia & histologia , Altitude , Pesos e Medidas Corporais/veterinária , Brasil
6.
Paediatr Int Child Health ; 33(2): 102-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23925284

RESUMO

BACKGROUND: Rotavirus is an important aetiological agent for severe diarrhoea in infants and young children worldwide. Anti-rotavirus antibodies in human colostrum and milk may interfere with rotavirus vaccination seroconversion. AIMS: To verify the presence of anti-rotavirus secretory IgA antibodies (SIgA) and the neutralizing capacity of 30 colostrum and 30 milk samples from Brazilian women in two different centres and analyze their persistence throughout lactation. METHODS: Colostrum and milk samples from healthy nursing mothers were tested for the presence of anti-rotavirus SIgA using conventional ELISA and their capacity to neutralize rotavirus using MA-104 cell cultures. Total IgA concentrations and anti-rotavirus SIgA levels were measured in samples collected from three mothers during 90 or 240 days of the lactation period. RESULTS: Colostrum samples showed higher levels of anti-rotavirus SIgA and higher neutralizing ability than in milk. However, these antibodies levels were not statistically different. In addition, there was no correlation between antibody levels and the neutralizing activity observed in colostrum and milk samples. Follow-up of three mothers demonstrated the persistence of anti-rotavirus and total IgA levels throughout lactation. CONCLUSIONS: These results support the encouragement of breastfeeding as a mechanism of protection against rotavirus infection in lactating infants. Components other than SIgA antibodies might play an important role in virus neutralization.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Colostro/imunologia , Imunoglobulina A Secretora/imunologia , Leite Humano/imunologia , Rotavirus/imunologia , Anticorpos Neutralizantes/análise , Anticorpos Antivirais/análise , Brasil , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina A Secretora/análise , Testes de Neutralização
7.
Braz J Biol ; 73(4): 887-93, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24789407

RESUMO

This study aimed to identify differences in wing shape among populations of Melipona quadrifasciata anthidioides obtained in 23 locations in the semi-arid region of Bahia state (Brazil). Analysis of the Procrustes distances among mean wing shapes indicated that population structure did not determine shape variation. Instead, populations were structured geographically according to wing size. The Partial Mantel Test between morphometric (shape and size) distance matrices and altitude, taking geographic distances into account, was used for a more detailed understanding of size and shape determinants. A partial Mantel test between morphometris (shape and size) variation and altitude, taking geographic distances into account, revealed that size (but not shape) is largely influenced by altitude (r = 0.54 p < 0.01). These results indicate greater evolutionary constraints for the shape variation, which must be directly associated with aerodynamic issues in this structure. The size, however, indicates that the bees tend to have larger wings in populations located at higher altitudes.


Assuntos
Abelhas/anatomia & histologia , Abelhas/classificação , Asas de Animais/anatomia & histologia , Altitude , Animais , Brasil
8.
Acta cir. bras ; 20(supl.1): 178-184, 2005.
Artigo em Português | LILACS | ID: lil-474168

RESUMO

PURPOSE: To determine the concentration of total secretory IgA and evaluate the repertoire of IgA antibodies to enteropathogenic Escherichia coli and Shigella flexneri antigens in colostrums and milk from mothers in Natal, RN. METHODS: The sample was constituted by 22 healthy clinically women whose babies were born at public hospital in Natal, RN. To determine total secretory IgA a radial immunedifusion tecnique (Mancini et al, 1965), was employed and to detect specific antibodies, immuneenzimatic assays, ELISA was used. RESULTS: The median values of total secretory IgA concentration presented individual variations with high levels in colostrums samples, decreasing during lactation, it was observed a p < 0.001 among the samples from the first day of lactation, to the thirtieth for total IgA concentration. All the donators present in colostrum and milk specific antibodies to Escherichia coli enteropathogenic (EPEC) and Shigella flexneri with titles higer in colostrum. There was parallel and directional pattern between total IgA and IgA anti-EPEC and Shegella flexneri, during period. CONCLUSION: The concentrations of total SIgA and specific antibodies to enteropathogenic Escherichia coli and Shigella flexneri in colostrums and milk in our study do not differ from others accomplished among populations with the same social and econimic features, stressing the importance of human milk as a protector agent against pathogens.


Assuntos
Humanos , Feminino , Gravidez , Lactente , Adolescente , Adulto , Anticorpos Antibacterianos/análise , Colostro/imunologia , Escherichia coli/imunologia , Imunoglobulina A Secretora/análise , Leite Humano/imunologia , Shigella flexneri/imunologia , Brasil , Aleitamento Materno , Diarreia Infantil/microbiologia , Diarreia Infantil/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Fatores Imunológicos/análise , Fezes/microbiologia , Lactação/imunologia , Fatores de Tempo
9.
Braz J Biol ; 64(3B): 563-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15619994

RESUMO

We examined the spatial implications of maximum flight distance for several species of stingless bees. Data suggested that maximum flight distance in Meliponini is a function of body size, especially generalized wing size, which can be estimated through principal component analysis. For six species of stingless bees, flight distances and generalized wing sizes were highly correlated (r = 0.938). This indicates that species of Meliponini occupy an effectively larger area as body size increases, which has important implications in the spatial dynamics of local populations restricted to forest fragments. We also used the fitted linear regression model to estimate the maximum flight distance for 12 other species of Meliponini. The results of this research may provide insights for future studies of biological conservation.


Assuntos
Abelhas/anatomia & histologia , Tamanho Corporal , Voo Animal/fisiologia , Animais , Abelhas/fisiologia , Ecossistema , Modelos Lineares
10.
Braz. j. biol ; 64(3b): 563-568, ago. 2004. tab, graf
Artigo em Inglês | LILACS | ID: lil-393521

RESUMO

Neste trabalho analisamos as implicações espaciais da distância máxima de vôo para algumas espécies de meliponíneos. Os dados sugerem que a distância máxima de vôo em meliponíneos está relacionada ao tamanho do corpo, especialmente ao tamanho generalizado das asas, que pode ser estimado utilizando análises de componentes principais. Uma análise utilizando seis espécies de meliponíneos evidenciou que o tamanho generalizado das asas está fortemente correlacionado à distância de vôo (r = 0,938). Isso sugere que espécies de meliponíneos ocupam área efetivamente maior quanto maior for o tamanho do corpo, trazendo importantes implicações para a dinâmica espacial de populações locais restritas a áreas fragmentadas. Neste trabalho, também utilizamos um modelo de regressão linear a fim de estimar as distâncias máximas de vôo para 12 outras espécies de meliponíneos. Esta pesquisa fornece subsídios para futuros estudos relacionados à conservação da biodiversidade.


Assuntos
Animais , Abelhas , Constituição Corporal , Voo Animal , Ecologia , Modelos Lineares
11.
Angiology ; 34(6): 412-7, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6346961

RESUMO

Aneurysms caused by atherosclerosis are relatively frequent, as a consequence of the high incidence of this degenerative disease of the arteries. Other types of aneurysm, for example, those of infectious etiology, are more uncommon. Bacterias and fungi are able to cause aneurysms in several parts of the arterial tree. Stengel et al (1943), in a review of world literature described 217 cases of mycotic aneurysms. The Stedman's Medical Dictionary refers to a special type of aneurysm observed in horses, caused by intra-vascular migration of a worm, the Strongylus vulgaris. It has been named verminous aneurysm and generally involves the mesenteric arteries. We haven't found in medical literature any similar observations refering to human cases. The purpose of this paper is to describe a case of aneurysm the etiology of which we have imputed to the filaria (Wuchereria bancrofti). This case was observed in Marcilio Dias Naval Hospital, Rio de Janeiro, Brazil.


Assuntos
Aneurisma Infectado/etiologia , Filariose , Adulto , Humanos , Masculino , Wuchereria bancrofti
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