12 research outputs found

    Trypsin-Like Serine Proteases in Lutzomyia longipalpis – Expression, Activity and Possible Modulation by Leishmania infantum chagasi

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    Background: Midgut enzymatic activity is one of the obstacles that Leishmania must surpass to succeed in establishing infection. Trypsins are abundant digestive enzymes in most insects. We have previously described two trypsin cDNAs of L. longipalpis: one (Lltryp1) with a bloodmeal induced transcription pattern, the other (Lltryp2) with a constitutive transcription pattern. We have now characterized the expression and activity of trypsin-like proteases of Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Brazil. Methodology and Principal Findings: In order to study trypsin expression profiles we produced antibodies against peptides specific for Lltryp1 and Lltryp2. The anti-Lltryp1-peptide antibody revealed a band of 28 kDa between 6 and 48 hours. The anti-Lltryp2 peptide antibody did not evidence any band. When proteinaceous substrates (gelatin, hemoglobin, casein or albumin) were co-polymerized in polyacrylamide gels, insect midguts obtained at 12 hours after feeding showed a unique proteolytic pattern for each substrate. All activity bands were strongly inhibited by TLCK, benzamidine and 4-amino-benzamidine, indicating that they are trypsin-like proteases. The trypsin-like activity was also measured in vitro at different time points after ingestion of blood or blood containing Leishmania infantum chagasi, using the chromogenic substrate BArNA. L. longipalpis females fed on blood infected with L. i. chagasi had lower levels of trypsin activity after 12 and 48 hours than non-infected insects, suggesting that the parasite may have a role in this modulation. Conclusions and Significance: Trypsins are important and abundant digestive enzymes in L. longipalpis. Protein production and enzymatic activity followed previously identified gene expression of a blood modulated trypsin gene. A decrease of enzymatic activity upon the parasite infection, previously detected mostly in Old World vectors, was detected for the first time in the natural vector-parasite pair L. longipalpis-L. i. chagasi

    Prevalência de infecção do colo do útero pelo HPV no Brasil: revisão sistemática

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    OBJETIVO: Analisar a prevalência de infecção pelo vírus do papiloma humano (HPV) em mulheres no Brasil. MÉTODOS: Revisão sistemática que incluiu artigos recuperados em busca livre nos portais PubMed e Biblioteca Virtual em Saúde, em abril/2009, utilizando-se os termos "human papillomavirus", "HPV", "prevalence" e "Brazil". Dos 155 artigos identificados, 82 permaneceram após leitura de título e resumo e foram submetidos à leitura integral, sendo selecionados 14 artigos. RESULTADOS: Os artigos sobre o tema foram publicados entre 1989 e 2008. Os 14 artigos representaram estudos de quatro regiões brasileiras (Sudeste 43%, Sul 21,4%, Nordeste 21,4% e Norte 7,1%). Nove artigos relatavam estudos transversais. Em oito utilizaram-se técnicas moleculares para tipagem do HPV e em sete deles utilizou-se captura híbrida para detecção do HPV. As populações estudadas variaram de 49 a 2.329 mulheres. A prevalência geral de infecção do colo do útero pelo HPV variou entre 13,7% e 54,3%, e para as mulheres com citologia normal, variou entre 10,4% e 24,5%. Quatro estudos relataram os tipos de HPV mais freqüentes, segundo resultado de citologia. CONCLUSÕES: As técnicas de citologia disponíveis resultam em diversas classificações e estimativas de prevalência do HPV. Contudo, considerando separadamente os estudos segundo a técnica utilizada, observa-se que a prevalência do HPV tem aumentado. O HPV16 foi o tipo mais freqüente entre as mulheres, independentemente do resultado de citologia. A concentração dos estudos na região Sudeste do País, especialmente nas regiões metropolitanas, mostra que investigações adicionais serão necessárias para aumentar a abrangência das informações disponíveis sobre as mulheres brasileiras.OBJETIVO: Analizar la prevalencia de infección por el virus de papiloma humano en mujeres en Brasil. MÉTODOS: Revisión sistemática que incluyó artículos recuperados en búsqueda libre en las páginas de datos PubMed y Biblioteca Virtual en Salud, en abril/2009, utilizándose los términos "human papillomavirus", "HPV", "prevalence" y "Brazil". De los 155 artículos identificados 82 se mantuvieron luego de leer el título y el resumen y fueron leídos de forma íntegra, siendo seleccionados 14 artículos. RESULTADOS: Los artículos sobre el tema fueron publicados entre 1989 y 2008. Los 14 artículos representaron estudios de cuatro regiones brasileras (Sureste - 43%, Sur - 21,4%, Noreste - 21,4% y Norte - 7,1%). Nueve artículos relatan estudios transversales. En ocho se utilizaron técnicas moleculares para tipaje del HPV e siete de ellos se utilizó captura híbrida para detección del HPV. Las poblaciones estudiadas variaron de 49 a 2.329 mujeres. La prevalencia general de infección de cuello de útero por el HPV varió entre 13,7% y 54,3%, y para las mujeres con citología normal, varió entre 10,4% y 24,5%. Cuatro estudios relataron los tipos de HPV más frecuentes, según resultado de citología. CONCLUSIONES: Las técnicas de citología disponibles resultan en diversas clasificaciones y estimaciones de prevalencia del HPV. Sin embargo, considerando separadamente los estudios según la técnica utilizada, se observa que la prevalencia del HPV ha aumentado. El HPV16 fue el tipo más frecuente entre las mujeres, independientemente del resultado de citología. La concentración de los estudios en la región Sureste del Brasil, especialmente en las regiones metropolitanas, muestra que las investigaciones adicionales serán necesarias para aumentar la amplitud de las informaciones disponibles sobre las mujeres brasileñas.OBJECTIVE: To assess the prevalence of human papillomavirus (HPV) infection in women in Brazil. METHODS: A systematic literature review was conducted with an active search in PubMed and Virtual Health Library databases using the terms "human papillomavirus," "HPV," "prevalence," and "Brazil". Of 155 articles retrieved, 82 were selected after reading their title and abstract. After a thorough examination, 14 articles were included in the study. RESULTS: The 14 articles selected were published between 1989 and 2008 and comprised studies from four Brazilian macroregions (Southeast 43%; South 21.4%; Northeast 21.4%; and North 7.1%). Nine were cross-sectional studies. Eight articles used polymerase chain reaction and seven used hybrid capture for HPV detection. The study samples ranged from 49 to 2,329 women. The overall prevalence of HPV cervical infection was between 13.7% and 54.3%; and women with cytologically normal results had 10% to 24.5% prevalence of HPV cervical infection. Four articles described the most common HPV types. CONCLUSIONS: The cytology techniques available use different classifications leading to different HPV prevalence estimates. However, considering the studies individually according to the detection technique used, the HPV prevalence has increased. HPV16 was the most prevalent type among women, regardless of the cytology result. The concentration of studies in the Southeast region, especially in metropolitan regions, evidences that further investigations are needed to improve information coverage of Brazilian women

    Cloning and characterization of a V-ATPase subunit C from the American visceral leishmaniasis vector Lutzomyia longipalpis modulated during development and blood ingestion

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    Visceral leishmaniasis (VL) is a serious tropical disease that affects approximately 500 thousand people worldwide every year. In the Americas, VL is caused by the parasite Leishmania (Leishmania) infantum chagasi mainly transmitted by the bite of the sand fly vector Lutzomyia longipalpis. Despite recent advances in the study of interaction between Leishmania and sand flies, very little is known about sand fly protein expression profiles. Understanding how the expression of proteins may be affected by blood feeding and/or presence of parasite in the vector's midgut might allow us to devise new strategies for controlling the spread of leishmaniasis. In this work, we report the characterization of a vacuolar ATPase subunit C from L. longipalpis by screening of a midgut cDNA library with a 220 bp fragment identified by means of differential display reverse transcriptase-polymerase chain reaction analysis. The expression of the gene varies along insect development and is upregulated in males and bloodfed L. longipalpis, compared to unfed flies

    Salivary gland proteome of the human malaria vector, Anopheles campestris-like (Diptera Culicidae)

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    Anopheles campestris-like is proven to be a high-potential vector of Plasmodium vivax in Thailand. In this study, A. campestris-like salivary gland proteins were determined and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional gel electrophoresis, and nano-liquid chromatography-mass spectrometry. The total amount of salivary gland proteins in the mosquitoes aged 3-5 days was approximately 0.1 ± 0.05 μg/male and 1.38 ± 0.01 μg/female. SDS-PAGE analysis revealed at least 12 major proteins found in the female salivary glands and each morphological region of the female glands contained different major proteins. Two-dimensional gel electrophoresis showed approximately 20 major and several minor protein spots displaying relative molecular masses from 10 to 72 kDa with electric points ranging from 3.9 to 10. At least 15 glycoproteins were detected in the female glands. Similar electrophoretic protein profiles were detected comparing the male and proximal-lateral lobes of the female glands, suggesting that these lobes are responsible for sugar feeding. Blood-feeding proteins, i.e., putative 5'-nucleotidase/apyrase, anti-platelet protein, long-form D7 salivary protein, D7-related 1 protein, and gSG6, were detected in the distal-lateral lobes (DL) and/or medial lobes (ML) of the female glands. The major spots related to housekeeping proteins from other arthropod species including Culex quinquefasciatus serine/threonine-protein kinase rio3 expressed in both male and female glands, Ixodes scapularis putative sil1 expressed in DL and ML, and I. scapularis putative cyclophilin A expressed in DL. These results provide information for further study on the salivary gland proteins of A. campestris-like that are involved in hematophagy and disease transmission
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