Aspectos de patogenicidade e relacionamento genético de isolados clínicos vaginas e anais de Candida albicans oriundos de pacientes com candidíase vulvovaginal

Vulvovaginal candidiasis (VVC) is one of the most common causes of vaginitis and affects about 75% of women of reproductive age. The majority of cases (80 to 90%) are due to C. albicans, the most virulent species of the genus Candida. Virulence attributes are scarcely investigated and the source of infection remains uncertain. Objective: This study aimed to evaluate the virulence factors and genotypes of clinical isolates of C. albicans sequentially obtained from the anus and vagina of patients with sporadic and recurrent VVC. Materials and methods: We analyzed 62 clinical isolates of C. albicans (36 vaginal and 26 anal strains). Direct examination of vaginal and anal samples and colony forming units (CFU) counts were performed. Yeasts were identified using the chromogenic media CHROMagar Candida® and by classical methodology, and phenotypically characterized regarding to virulence factors, including the ability to adhere to epithelial cells, proteinase activity, morphogenesis and biofilm formation. The genotypes of the strains were investigated with ABC genotyping, microsatellite genotyping with primer M13 and RAPD. Results: We found 100% agreement between direct examination and culture of vaginal samples. Filamentous forms were present in most of the samples of vaginal secretion, which presented CFU counts significantly higher than the samples of anal secretion. There was no statistically significant difference between virulence factors of infecting vaginal isolates and those presented by colonizing anal isolates; as well as for the comparison of the vaginal isolates from patients with different clinical conditions (sporadic or recurrent VVC). There was a decrease in the ability to adhere to HBEC, morphogenesis and biofilm formation of the vaginal isolates during the progress of infection. There was an association between the ability to express different virulence factors and the clinical manifestations presented by the patients. Genotype A was the most prevalent (93.6%), followed by genotype C (6.4%). We found maintenance of the same ABC genotype and greater prevalence of microevolution for the vaginal strains of C. albicans sequentially obtained. Vaginal and anal isolates of C. albicans obtained simultaneously from the same patient presented the same ABC genotype and high genetic relatedness. Conclusion: It is noteworthy that the proliferation of yeast and bud-to-hypha transition are important for the establishment of CVV. The expression of virulence factors is important for the pathogenesis of VVC, although it does not seem to be determinant in the transition from colonization to infection or to the installation of recurrent condition. Genotype A seems to be dominant over the others in both vaginal and anal isolates of patients with VVC. The most common scenario was microevolution of the strains of C. albicans in the vaginal environment. It is suggested that the anal reservoir constituted a possible source of vaginal infection, in most cases assessed

Imunoexpressão das claudinas -1 e -7 em ameloblastomas e germes dentais humanos

We investigated the immunohistochemistry expression of claudins -1 and -7 in ameloblastoma and in human dental germs on the pattern of distribution (focal, regional or diffuse), the cells that expressed (if central or peripheral) and the location of that expression in the cell components recital membrane, cytoplasm and nucleus. Among the 29 cases of ameloblastoma, 24 were type solid and 6 unicystic. In 7 mandibular specimens of human fetuses found dental germs from the stage of bud to the crown. We note that the pattern of expression in the dental germs was variable for claudinas studied according to the cell type and stage of differentiation and was invariate only in the cells of stellate reticulum. In epithelium internal of enamel organ, claudin-1 has been decreasing with the progression of differentiation as to claudina-7 that was found in the cells of the peripheral papilla. For ameloblastoma the expression was more significant than that observed in dental germs. Fisher s exact test no found association between the expression of claudinas cells in central and peripheral and the type of ameloblastoma (solid or unicystic). Thus, in general the claudin-1 was positive in the central cell of 93,1% of the cases and in peripheral cells of 51,7%. The claudin-7 was expressed in the cells of all cases central and peripheral cells from 89,7%. For both claudins the distribution was predominantly diffuse cells both in central and peripheral cells. Given our findings it is suggested that the expression of claudins may be indicative of the involvement of these molecules in morphogenetics events culminating with the dental development and that possibly influence the development of neoplastic ameloblastoma

Caracterização do material particulado e avaliação do risco ocupacional e mecanismos moleculares associados à queima artesanal da castanha de caju

Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.

Caracterização do material particulado e avaliação do risco ocupacional e mecanismos moleculares associados à queima artesanal da castanha de caju

Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.