958 resultados para class III cells


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The sternal glands of the abdomen of Oxaea flavescens (Klug, 1807) consist of class III glandular cells around a reservoir constituted by branched folds of the intersegmental membrane of segments III, IV and V. The gland cells are rich in rough endoplasmic reticulum and produce a secretion with mucous aspect. The treatment with oxidated osmium and ruthenium red showed numerous Golgi regions in the cell and carbohydrates absorption from the haemolymph, respectively. The high degree of development of the glands suggests an important function to the species, although still unknown.

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The indices found are analysed as a whole and general conclusions are drawn from them which may be of use in understanding many of the problems offered by the local flora (Ilhéus). The first column of the tables presented indicates the biological form of the species, showing the nature of the flora and the constitution of the climax. A total of 200 species of phanerophyta were found; 69 macrophanerophyta (trees), 54 are mesophanerophyta (treelets) and 77 are nanophanerophyta (shrubs). The macrophanerophyta are consequently considered as dominants and the meso-and nanophanerophyta as codominants (the biological forms: chamaephyta, hemicriptophyta, criptophyta, geophyta, therophyta, epiphyta and hydrophyta are subdominants), the more so as the first cover 80% and the others more or less 50%. This points to a climax of trees and a local vegetation mainly composed of trees also. The smaller forms are left out as they are beyond the present scope of this sort of wort in Brazil. The third column of ecological formulae indicates the reaction of the constituent species to light (C = sciophilous, F = photophilous and I = indifferents), the biological types of vegetation (H = hygrophytes, X = xerophytes and M = mesophytes) and the fidelity of the species to the climax. Of the species studied: 25 are pioneers (P. Table I), 63 are accidentals (A. Table II), 35 are companion species (O. Table III), 19 show preferences (E. Table with vitality Vn), 44 are selective (S. Table V) and 13 exclusive species (L. Table VI). This leads to the conclusion that the vegetation of the region is in full reconstitution. As to the ecological characteristics of the 200 species studied, 89 are either pioneers (a class separated by the author) or accidentals; this means that the devastated zones are being reconstituted in the subsere both with members of the prisere and alien species. Of the remaining species, 54 are companion, or accompanying species, which appear in most subclimax, serclímax and quasiclimax associations, and 57 are real constituents of the local climax. As all the species except the pioneers, selectives and exclusives (xerophytes and mesophytes) may be considered as hygrophytes this type evidently predominantes in the region and may constitute a hygrophilous serclimax and quasiclímax. In regard to light 101 are sciophilous, 32 indiferents and 67 photophilous. This leads to the conclusion that the vegetation comprises mainly tolerant species, showing the hygrophilous and mesophilous character of the region with a vegetation composed mostly of trees. The presence a large number of sciophilous species is easy to understand as the hygrophilous and mesophilous habitats and the dominance of trees favour the germination and growth of tolerant species. The last two columns analyse the percentage of individuals present and the occurrent classes to which they belong: 92 species vary between 1 and 9%; 50 between to 10 and 19%; 36 between 20 and 29%; 14 between 30 and 39%; and 8 between 40 and 49%. Only 8 species belong to occurrence class V; 14 to classe IV; 36 to class III; 50 to class II; and 92 to class I. This leads to the conclusion that the local formation is very unsociable and very complex, though the median coverture is 80% and the number of species is very large. The analysis of the data also shows that the climax is being reconstituted in the subsere with elements drawn from the prisere and alien species introduced either by man (following desvastation) or by other consequent factors (such as brusque changes of microclimates due to total or partial destruction). This modifies the subclimax appreciably and apparently also the climax of the local regional subsere. As a final conclusion it is suggested that as in the subsere the pioneer formation is xerophilous, the prisere also beging as a xerosere; but as there are and probably always were hydrophilous formation evolving in the same climate, the local climax is composed of species with medium exactions, that is of relative mesophites.

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Purpose/Objective: Histone deacetylases (HDACs) deacetylate histones and transcriptional regulators thereby affecting numerous biological functions. Seven mammalian sirtuins (SIRT1-7) constitute the NAD-dependent class III subfamily of HDACs. Sirtuins are the center of great interest due to their regulatory role in the control of metabolism, ageing and age-related diseases. Up to now, little is known about the influence of sirtuins on immune responses, and nothing about the role of SIRT2. The aim of the study was to analyze the influence of SIRT2 knockout on immune cell development and innate immune responses in vitro and in vivo. Materials and methods: SIRT2 germline knockout were produced on a C57BL/6J background. The cellularity of thymus and spleen was assessed by flow cytometry (n = 3). Bone marrow derived macrophages (BMDMs) and dendritic cells (BMDCs) and splenocytes were stimulated with LPS, Pam3CSK4 lipopeptide, CpG ODN, E. coli, S. aureus, TSST-1, SEB, anti-CD3+ CD28 and concanavalin A (n = 3_8). TNF, IL-2, IL-6, IL-12p40 and IFNc production, SIRT1_7 and CD40 expression, and proliferation were quantified by real time-PCR, ELISA, flow cytometry and H3-thymidine incorporation. Mice (n = 6_16) were challenged with LPS, TNF/D-galactosamine, E. coli and K. pneumonia titrated to cause either mild or severe infections or shock. Blood was collected to quantify cytokines and bacteria. Mortality was checked regularly. Results: SIRT2 is the most expressed sirtuin in macrophages and myeloid DCs. To test whether SIRT2 impacts on innate immune responses, we generated SIRT2 germline knockout mice. SIRT2-/- mice born at the expected Mendelian ratio and develop normally. The proportions and absolute numbers of DN1-4, DP and SP thymocytes, and of T-cells (DN and SP, naı¨ve and memory), B-cells (immature and mature), DCs (cDCs and pDCs) and granulocytes in the spleen are similar in SIRT2+/+ and SIRT2-/- mice. SIRT2+/+ and SIRT2-/- BMDMs, BMDCs and splenocytes produce cytokines (RNA and protein), upregulate CD40, and proliferate to the same extent. SIRT2+/+ and SIRT2-/- mice respond similarly (cytokine blood levels, bacterial counts and mortality) to non-severe and lethal endotoxemia, E. coli peritonitis, K. pneumonia pneumonia and TNF-induced shock. Conclusions: SIRT2 knockout has no dramatic impact on the development of immune cells and on innate immune responses in vitro and in vivo. Considering that SIRT2 may participate to control metabolic homeostasis, we are currently assessing the impact of SIRT2 deficiency on innate immune responses under metabolic stress.

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OBJECTIVE: To investigate the impact of corticosteroids (CS) on the viral-specific T-cell response, in particular the JC virus (JCV)-specific one, in an attempt to determine the optimal timing of CS in the management of progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome (PML-IRIS). METHODS: A blood draw was performed before and 7 days after the administration of IV CS to 24 patients with relapsing multiple sclerosis (MS). The phenotypic pattern of T cells was determined by CCR7 and CD45RA. To assess the impact of CS treatment on proliferative response of JCV-, influenza-, and Epstein-Barr virus (EBV)-specific T cells, a thymidine incorporation proliferation assay was performed. An intracellular cytokine staining assay was performed to determine the effect of CS treatment on the production of cytokine by virus-specific T cells. JCV T-cell assays were performed only in JCV-infected patients with MS as detected by serologies (Stratify) or detection of JCV DNA in the urine by PCR. RESULTS: CS led T cells, CD4+ and CD8+, toward a less differentiated phenotype. There was a significant decrease of EBV-, influenza-, and JCV-specific T-cell proliferative response upon CS treatment. There was a significant decrease in the frequency of interferon (IFN) γ- and tumor necrosis factor (TNF) α-producing JCV-specific CD8+ T cells, but not EBV- or influenza-specific CD4+ or CD8+ T cells. CONCLUSIONS: CS have a profound impact on the virus-specific T-cell response, especially on JCV, suggesting that when CS are considered, they should not be given before the onset of clinical or radiologic signs of IRIS. Studies addressing directly patients with MS with natalizumab-caused PML are warranted. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that methylprednisolone treatment decreases the frequency of JCV-specific CD8+ T cells producing IFN-γ and TNFα, impairing control of JCV, suggesting this should be used to treat but not to prevent PML-IRIS. No clinical outcomes were measured.

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PURPOSE: The European Organisation for Research and Treatment of Cancer and National Cancer Institute of Canada trial on temozolomide (TMZ) and radiotherapy (RT) in glioblastoma (GBM) has demonstrated that the combination of TMZ and RT conferred a significant and meaningful survival advantage compared with RT alone. We evaluated in this trial whether the recursive partitioning analysis (RPA) retains its overall prognostic value and what the benefit of the combined modality is in each RPA class. PATIENTS AND METHODS: Five hundred seventy-three patients with newly diagnosed GBM were randomly assigned to standard postoperative RT or to the same RT with concomitant TMZ followed by adjuvant TMZ. The primary end point was overall survival. The European Organisation for Research and Treatment of Cancer RPA used accounts for age, WHO performance status, extent of surgery, and the Mini-Mental Status Examination. RESULTS: Overall survival was statistically different among RPA classes III, IV, and V, with median survival times of 17, 15, and 10 months, respectively, and 2-year survival rates of 32%, 19%, and 11%, respectively (P < .0001). Survival with combined TMZ/RT was higher in RPA class III, with 21 months median survival time and a 43% 2-year survival rate, versus 15 months and 20% for RT alone (P = .006). In RPA class IV, the survival advantage remained significant, with median survival times of 16 v 13 months, respectively, and 2-year survival rates of 28% v 11%, respectively (P = .0001). In RPA class V, however, the survival advantage of RT/TMZ was of borderline significance (P = .054). CONCLUSION: RPA retains its prognostic significance overall as well as in patients receiving RT with or without TMZ for newly diagnosed GBM, particularly in classes III and IV.

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Neurofibromatosis type 1 (NF1) is an autosomal dominant cancer predisposition syndrome that affects about 1 in 3500 individuals worldwide. NF1 is caused by mutations in the NF1 gene that encodes the tumor suppressor protein neurofibromin, an inactivator of the Ras oncogene. The hallmarks of NF1 include pigmentary lesions of the skin, Lisch nodules of the iris and cutaneous neurofibromas. Cutaneous neurofibromas are benign tumors composed of all the cell types of normal peripheral nerve. The traditional view of neurofibroma development has been that cutaneous neurofibromas arise from the disruption of the small nerve tributaries of the skin and subsequent proliferation of the resident cells. The second hit mutation in the NF1 gene has been considered as a prerequisite for neurofibroma development. The second hit is detectable in a subpopulation of primary Schwann cells cultured from neurofibromas. This thesis challenges the traditional concept of neurofibroma development. The results show that cutaneous neurofibromas are intimately associated with hair follicular structures and contain multipotent precursor cells (NFPs), suggesting that neurofibromas may arise from the multipotent cells which reside in hair follicles. Furthermore, this study presents that neurofibroma-derived Schwann cells that harbor bi-allelic inactivation in the NF1 gene express HLA class II genes and may act as nonprofessional antigen presenting cells. The CD4- and FoxP3-positive cells detected in cutaneous neurofibromas suggest that these cells may represent regulatory T cells (Tregs) which interact with HLA II –positive cells and aid the tumor cells in hiding from the immune system and are thus mediators of immune tolerance. This thesis also investigated neurofibroma development in the oral cavity and the use of different biomarkers to characterize cellular differentiation in neurofibromas. The results revealed that oral neurofibromas are not rare, but they usually appear as solitary lesions contrary to multiple cutaneous neurofibromas and present high heterogeneity within and between tumors. The use of class III beta-tubulin as a marker for neuronal differentiation led to an unexpected finding showing that multiple cell types express class III beta-tubulin during mitosis. The increased understanding of the multipotency of tumor cells, cellular differentiation and ability to hide from immune system will aid in the development of future treatments. Specifically, targeting Tregs in NF1 patients could provide a novel therapeutic approach to interfere with the development of neurofibromas.

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The aim of this study was to determine if bone marrow mononuclear cell (BMMC) transplantation is safe for moderate to severe idiopathic dilated cardiomyopathy (IDC). Clinical trials have shown that this procedure is safe and effective for ischemic patients, but little information is available regarding non-ischemic patients. Twenty-four patients with IDC, optimized therapy, age 46 ± 11.6 years, 17 males, NYHA classes II-IV, and left ventricular ejection fraction <35% were enrolled in the study. Clinical evaluation at baseline and 6 months after stem cell therapy to assess heart function included echocardiogram, magnetic resonance imaging, cardiopulmonary test, Minnesota Quality of Life Questionnaire, and NYHA classification. After cell transplantation 1 patient showed a transient increase in enzyme levels and 2 patients presented arrhythmias that were reversed within 72 h. Four patients died during follow-up, between 6 and 12 weeks after therapy. Clinical evaluation showed improvement in most patients as reflected by statistically significant decreases in Minnesota Quality of Life Questionnaire (63 ± 17.9 baseline vs 28.8 ± 16.75 at 6 months) and in class III-IV NYHA patients (18/24 baseline vs 2/20 at 6 months). Cardiopulmonary exercise tests demonstrated increased peak oxygen consumption (12.2 ± 2.4 at baseline vs 15.8 ± 7.1 mL·kg-1·min-1 at 6 months) and walked distance (377.2 ± 85.4 vs 444.1 ± 77.9 m at 6 months) in the 6-min walk test, which was not accompanied by increased left ventricular ejection fraction. Our findings indicate that BMMC therapy in IDC patients with severe ventricular dysfunction is feasible and that larger, randomized and placebo-controlled trials are warranted.

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Viral fusion proteins mediate the merger of host and viral membranes during cell entry for all enveloped viruses. Baculovirus glycoprotein gp64 (gp64) is unusual in promoting entry into both insect and mammalian cells and is distinct from established class I and class II fusion proteins. We report the crystal structure of its postfusion form, which explains a number of gp64's biological properties including its cellular promiscuity, identifies the fusion peptides and shows it to be the third representative of a new class (III) of fusion proteins with unexpected structural homology with vesicular stomatitis virus G and herpes simplex virus type 1 gB proteins. We show that domains of class III proteins have counterparts in both class I and II proteins, suggesting that all these viral fusion machines are structurally more related than previously thought.

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Of the three classes of true phosphoinositide (PI) 3-kinases, the class II subdivision, which consists of three isoforms, PI3K-C2alpha, PI3K-C2beta and PI3K-C2gamma, is the least well understood. There are a number of reasons for this. This class of PI 3-kinase was identified exclusively by PCR and homology cloning approaches and not on the basis of cellular function. Like class I PI 3-kinases, class II PI 3-kinases are activated by diverse receptor types. To complicate the elucidation of class II PI 3-kinase function further, their in vitro substrate specificity is intermediate between the receptor activated class I PI 3-kinases and the housekeeping class III PI 3-kinase. The class II PI 3-kinases are inhibited by the two commonly used PI 3-kinase family selective inhibitors, wortmannin and LY294002, and there are no widely available, specific inhibitors for the individual classes or isoforms. Here the current state of understanding of class II PI 3-kinase function is reviewed, followed by an appraisal as to whether there is enough evidence to suggest that pharmaceutical companies, who are currently targeting the class I PI 3-kinases in an attempt to generate anticancer agents, should also consider targeting the class II PI 3-kinases.

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A hemofagocitose reativa ou síndrome de ativação macrofágica (SAM) é uma complicação das doenças inflamatórias sistêmicas, causada por expansão de células T e macrófagos, com produção maciça de citocinas pró-inflamatórias, ocorrendo mais freqüentemente na artrite idiopática juvenil sistêmica e raramente no lúpus eritematoso sistêmico juvenil (LESJ). OBJETIVO: Relatar um caso de LESJ que evoluiu com SAM precipitada por infecção e infarto esplênico, com desfecho fatal. RELATO DE CASO: Uma menina de 7 anos, com diagnóstico de LESJ desde os 5 anos, evoluiu com artrite em atividade, alopecia intensa, citopenias, cefaléia, infecções respiratórias recorrentes e elevação intermitente de transaminases. Os anticorpos anti-DNA e anticardiolipina IgG e IgM foram identificados e a biópsia renal evidenciou glomerulonefrite lúpica de classe III. A paciente foi tratada com pulso de metilprednisolona, prednisona, azatioprina e hidroxicloroquina. Após dois anos, na vigência de pneumonia apresentou abdome agudo e convulsões, evoluindo para o choque hemorrágico fatal após esplenectomia, que evidenciou infarto esplênico e infiltração maciça por macrófagos hemofagocíticos CD163+. CONCLUSÃO: A revisão do desfecho sugere a SAM precipitada por infecção e sobreposta a atividade inflamatória do lúpus com febre persistente, citopenias, disfunção hepática, hepatomegalia e esplenomegalia, como efeitos do excesso de produção de citocinas. Os anticorpos anticardiolipina podem ter tido papel precipitante na coagulopatia, que resultou infarto esplênico e choque hemorrágico.

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O presente estudo avaliou as modificações no perfil facial de 15 pacientes portadores de má oclusão Classe III esquelética que foram submetidos a tratamento ortodôntico pré-cirúrgico e cirurgia ortognática bimaxilar estabilizada com fixação rígida. Oito pacientes foram submetidos à mentoplastia. Foram utilizadas telerradiografias pré-cirúrgicas (T1) e pós-cirúrgicas (T2) com um intervalo mínimo de 6 meses. Foram analisados deslocamentos horizontais e verticais em pontos do tecido ósseo e tecido mole. Foi realizada uma comparação entre os casos tratados com e sem mentoplastia (teste t) mostrando não haver diferenças entre os grupos. A regressão linear múltipla evidenciou uma correlação significante no sentido horizontal para os pontos Pg e Pgm e vertical para os pontos Me e Mem. Foi encontrada baixa correlação para movimentos no sentido horizontal nos pontos Sena e A, e para os pontos Pn, Sn e Ph. No sentido vertical, os deslocamentos mais evidentes foram entre os pontos Pg, Gn e Me e Sena e A, porém com correlações de baixa intensidade.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Este é um primeiro relato sobre a presença de células glandulares no tegumento lateral do mesotórax de abelhas da subfamília Meliponinae. Trata-se de células glandulares de classe III que estão presentes em rainhas, operárias e machos. As glândulas são mais desenvolvidas nas rainhas que nas operárias e nestas mais que nos machos.

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Foram estudadas a ocorrência e a morfologia de glândulas tegumentares presentes no abdome de fêmeas de Melissoptila richardiae. Os resultados mostram que nesta espécie, células glandulares da classe III são encontradas de duas formas: isoladas nos tergitos e esternitos III e IV e formando um aglomerado de unidades glandulares bilateralmente, entre os segmentos III e IV, os quais liberam seu produto de secreção em um reservatório originado a partir da membrana intersegmental. Os resultados sugerem que o produto secretado é lipídico e, provavelmente volátil.

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In the present work, the antitumor effect of fastuosain, a cysteine proteinase from Bromelia fastuosa, was investigated. In the intravenous model of lung colonization in C57Bl/6 mice, fastuosain and bromelain injected intraperitoneally were protective, and very few nodules of B16F10-Nex2 melanoma cells were detected. Tumor cells treated with fastuosain showed reduced expression of CD44 and decreased invasion through Matrigel, lost their cytoplasmic extensions and substrate adherence, and became round and detached, forming strongly bound cell clusters in suspension. Peritoneal cells recruited and activated by fastuosain treatment ( mainly monocytic cells and lymphocytes) migrated to the lung, where pulmonary melanoma metastases grew. Adoptive transference of peritoneal cells recruited by fastuosain had no protective effect against lung metastases in recipient mice. Treatment of green fluorescent protein - chimeric animals with fastuosain did not change the number of cells that migrated to the lung, compared to PBS-injected control mice, but the number of positive major histocompatibility complex class II cells increased with fastuosain treatment. Murine antibodies against fastuosain, bromelain, and cathepsins B and L cross-reacted in ELISA and recognized surface and cytoplasmic components expressed on B16F10-Nex2 cells. Anti-fastuosain antibodies were cytotoxic/lytic to B16F10-Nex2 cells. Antitumor effects of fastuosain involve mainly the direct effect of the enzyme and elicitation of protective antibodies.