998 resultados para Entomoftoromicose cutâneo-mucosa


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Many mucosal pathogens invade the host by initially infecting the organized mucosa-associated lymphoid tissue (o-MALT) such as Peyer's patches or nasal cavity-associated lymphoid tissue (NALT) before spreading systemically. There is no clear demonstration that serum antibodies can prevent infections in o-MALT. We have tested this possibility by using the mouse mammary tumor virus (MMTV) as a model system. In peripheral lymph nodes or in Peyer's patches or NALT, MMTV initially infects B lymphocytes, which as a consequence express a superantigen (SAg) activity. The SAg molecule induces the local activation of a subset of T cells within 6 days after MMTV infection. We report that similar levels of anti-SAg antibody (immunoglobulin G) in serum were potent inhibitors of the SAg-induced T-cell response both in peripheral lymph nodes and in Peyer's patches or NALT. This result clearly demonstrates that systemic antibodies can gain access to Peyer's patches or NALT.

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In the present study, we have investigated the anatomic distribution in blood and gut mucosal tissues of memory poxvirus-specific CD4 and CD8 T cells in subjects vaccinated with smallpox and compared it with vector (NYVAC)-specific and HIV insert-specific T-cell responses induced by an experimental DNA-C/ NYVAC-C vaccine regimen. Smallpox-specific CD4 T-cell responses were present in the blood of 52% of the subjects studied, while smallpox-specific CD8 T cells were rarely detected (12%). With one exception, smallpox-specific T cells were not measurable in gut tissues. Interestingly, NYVAC vector-specific and HIV-specific CD4 and CD8 T-cell responses were detected in almost 100% of the subjects immunized with DNA-C/NYVAC-C in blood and gut tissues. The large majority (83%) of NYVAC-specific CD4 T cells expressed α4β7 integrins and the HIV coreceptor CCR5. These results demonstrate that the experimental DNA-C/NYVAC-C HIV vaccine regimen induces the homing of potentially protective HIV-specific CD4 and CD8 T cells in the gut, the port of entry of HIV and one of the major sites for HIV spreading and the depletion of CD4 T cells.

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Se presenta un estudio descriptivo de prevalencia de patología de la mucosa bucal, en una muestra de 1491 pacientes, visitados en la Clínica Odontológica Universitaria de la Facultad de Odontología de la Universidad de Barcelona. Entre los objetivos planteados se persigue conocer la asociación de las lesiones más prevalentes con la patología sistémica y con los hábitos tóxicos. Las lesiones más prevalentes fueron las clasificadas en el grupo de lesiones blancas. No se pudo confirmar una mayor asociación de la patología bucal en general con la patología sistémica, pero sí una mayor prevalencia de patología bucal en pacientes con hábitos tóxicos, particularmente tabaquismo.

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Cervical cancer, the second leading cause of cancer mortality in women worldwide, results from infection with a subset of human papillomaviruses (HPV), HPV-16 being the most prevalent type. The available prophylactic vaccines are an effective strategy to prevent this cancer in the long term. However, they only target 70-80% of all cervical cancers and cannot control existing HPV infections and associated lesions. Therapeutic vaccines are thus necessary for women who cannot benefit from prophylactic vaccination. Induction of protective immune responses in the genital mucosa (GM) may be crucial for efficacy of HPV therapeutic vaccines. We report here that mice that received a single subcutaneous (s.c.) vaccination of an adjuvanted long synthetic HPV16 E7(1-98) polypeptide showed induction of 100% tumor protection against s.c. TC-1 tumors and that tumor regression was mainly provided by CD8 T cells. In vivo cytotoxic assay revealed high E7-specific cytolytic T lymphocytes activity in spleen and in genital draining lymph nodes (LN), and E7-specific CD8 T cells could be detected in GM by tetramer staining. More importantly, high-avidity E7-specific INF-gamma secreting CD8 T cells were induced not only in blood, spleen and LN but also in GM of vaccinated mice, thus providing evidence that a parenteral vaccination may be sufficient to provide regression of genital tumors. In addition, there was no correlation between the responses measured in blood with those measured in GM, highlighting the necessity and relevance to determine the immune responses in the mucosa where HPV-tumors reside.

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Currently a growing interest to improve the pharmacological therapy exists, not only by the production and the appearance of new drugs, but guaranteeing that the uses of those which already exist, become more effective. In fact, the conventional pharmaceutical formulations of different drugs present a few secondary effects due to oral administration. In order to avoid these undesired side effects, the purpose of current therapeutic is the development and research of formulations as an alternative to others routes of administration. Therefore, in spite of the undoubtedly complete parenteral absorption, the transdermal and transbuccal routes appear to be a rather attractive alternative to provide an efficient absorption. In this chapter a new technological, biopharmaceutical and pharmacokinetic approach of strategies for application on skin and buccal mucosa are reported. In the future new transdermal drug delivery systems will emerge to be more effective, equipped with an improved aesthetic appearance, better adherence and greater diffusion. But to reach these aims, it is necessary previous knowledge of histology and physiology of skin, and factors involved in the penetration of drugs through it.

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The bone marrow constitutes a favorable environment for long-lived antibody-secreting plasma cells, providing blood-circulating antibody. Plasma cells are also present in mucosa-associated lymphoid tissue (MALT) to mediate local frontline immunity, but how plasma cell survival there is regulated is not known. Here we report that a proliferation-inducing ligand (APRIL) promoted survival of human upper and lower MALT plasma cells by upregulating expression of the antiapoptotic proteins bcl-2, bcl-xL, and mcl-1. The in situ localization of APRIL was consistent with such a prosurvival role in MALT. In upper MALT, tonsillar epithelium produced APRIL. Upon infection, APRIL production increased considerably when APRIL-secreting neutrophils recruited from the blood infiltrated the crypt epithelium. Heparan sulfate proteoglycans (HSPGs) retained secreted APRIL in the subepithelium of the infected zone to create APRIL-rich niches, wherein IgG-producing plasma cells accumulated. In lower MALT, neutrophils were the unique source of APRIL, giving rise to similar niches for IgA-producing plasmocytes in villi of lamina propria. Furthermore, we found that mucosal humoral immunity in APRIL-deficient mice is less persistent than in WT mice. Hence, production of APRIL by inflammation-recruited neutrophils may create plasma cell niches in MALT to sustain a local antibody production.

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Head and neck cancer patients are at high risk for developing second primary tumors. This is known as field cancerization of the aero-digestive tract. In a previous study, we showed that patients with multiple primary tumors were more likely to have p53 mutations in histologically normal mucosae than patients presenting with an isolated tumor. Based on this observation, we postulated that p53 mutations in normal tissue samples of patients bearing a single primary tumor could have a clinical value as a biomarker for the risk of developing second primary tumors. Thirty-five patients presenting with a single primary tumor were followed-up for a median of 51 months (range 1 month to 10.9 years) after biopsies of histologically normal squamous cell mucosa had been analyzed for p53 mutations with a yeast functional assay at the time of the primary tumor. During this follow-up, recurrences and non-sterilization of the primary tumor, occurrence of lymph node metastases, and of second primary tumors were evaluated. Sixteen (45.7%) patients were found to have p53 mutations in their normal squamous cell mucosa, and 19 (54.3%) patients showed no mutation. No relationship was found between p53 mutations and the occurrence of evaluated events during follow-up. Notably, the rate of second primary tumors was not associated with p53 mutations in the normal squamous mucosa. The correlation between p53 mutations in histologically normal mucosae and the incidence of second primary tumors is generally low. The benefit of analyzing p53 mutations in samples of normal squamous cell mucosa in every patient with a primary tumor of the head and neck is doubtful.

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In adaptive immunity, Th17 lymphocytes produce the IL-17 and IL-22 cytokines that stimulate mucosal antimicrobial defenses and tissue repair. In this study, we observed that the TLR5 agonist flagellin induced swift and transient transcription of genes encoding IL-17 and IL-22 in lymphoid, gut, and lung tissues. This innate response also temporarily enhanced the expression of genes associated with the antimicrobial Th17 signature. The source of the Th17-related cytokines was identified as novel populations of CD3(neg)CD127(+) immune cells among which CD4-expressing cells resembling lymphoid tissue inducer cells. We also demonstrated that dendritic cells are essential for expression of Th17-related cytokines and so for stimulation of innate cells. These data define that TLR-induced activation of CD3(neg)CD127(+) cells and production of Th17-related cytokines may be crucial for the early defenses against pathogen invasion of host tissues.

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OBJECTIVE: An operative technique is described as a salvage treatment for severe subglottic and supraglottic laryngeal stenosis. In addition to expansion of the laryngeal framework with an anterior cartilage graft, as used in a classical laryngotracheal reconstruction, the scar tissue obliterating the airway lumen is excised and a mucosal graft is placed to reconstruct the inner lining of the airway. The graft is harvested from buccal mucosa. METHODS: The operative technique is outlined. Three cases, 2 paediatric and one adult, with complete or near complete laryngeal stenosis are presented where this operative technique was employed. In all patients several surgeries had been performed previously which were unsuccessful. RESULTS: In all 3 patients a patent airway was achieved with decannulation of the tracheostomy in the 2 paediatric patients. CONCLUSIONS: In patients with severe subglottic or supraglottic airway stenosis where other surgeries have failed, excision of endoluminal scar tissue and placement of a buccal mucosal graft, in addition to conventional laryngotracheal reconstruction, is a promising technique. In revision cases of subglottic stenosis cricotracheal resection might not be an option because of scarring from previous surgeries. This operation is an alternative, which allows an increase in the airway lumen by excising the scar tissue then re-lining the exposed internal lumen. The buccal mucosa reduces granulation formation and re-stenosis.

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Human cytomegalovirus-induced lesions resembling malignancies have been described in the gastrointestinal tract and include ulcerated or exophytic large masses. The aim of this study was to review the cases registered in the databases of two academic hospitals and formulate a hypothesis concerning the pathogenic mechanisms responsible for cytomegalovirus-induced pseudotumor development. All the diagnoses of human cytomegalovirus infections of the upper gastrointestinal tract recorded from 1991 to 2013 were reviewed. Cases of mucosal alterations misdiagnosed endoscopically as malignancies were selected. Large ulcers occurring in the stomach (three cases) and an irregular exophytic mass at the gastro-jejunal anastomosis were misdiagnosed endoscopically as malignancies (4 cases out of 53). Histologically, all lesions reflected hyperplastic mucosal changes with a prevalence of epithelial and stroma infected cells, without signs of cell atypia. The hypothesis presented is that the development of human cytomegalovirus-induced pseudotumors may be the morphological expression of chronic mucosa damage underlying long-term infection.

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This study aimed to verify the chloroform-methanol nymphicidal action of extracts of Annona mucosa leaves and seeds and of A. crassiflora seeds on second instar nymphs of rice stalk stink bug, Tibraca limbativentris. For each extract the concentrations of 0.5%, 1.0%, 2.0%, 4.0%, 8.0%, and two control treatments (water and Tween80®) were used. The results show that the seed extracts of A. mucosa and A. crassiflora have insecticidal activity against the T. limbativentris nymphs with statistical significance for all concentrations when compared with controls. The seed extract of A. mucosa showed the higher toxicity with greater than 75% mortality at a concentration of 1.0% in the first 24 h after application. The leaf extract of A. mucosa presented the lowest toxicity with no more than 40% mortality. The seed extract of A. crassiflora showed intermediate toxicity among all the tested extracts, and the nymph's mortality exceeded 80% for the highest concentration after 120 h of application. Considering these results, we were able to observe that the seeds extract of A. mucosa may be an alternative for the control of bed bug nymphs T. limbatriventris, especially for small producers.