992 resultados para morphology factor


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

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Aims: Development of effective immune-based therapies for patients with non-small-cell lung carcinoma (NSCLC) depends on an accurate characterization of complex interactions that occur between immune cells and the tumour environment. Methods and results: Innate and adaptive immune responses were evaluated in relation to prognosis in 65 patients with surgically excised NSCLC. Immunohistochemistry and morphometry were used to determine the abundance and distribution of immune cells. We found low numbers of immune cells and levels of cytokines in the tumour environment when compared with surrounding parenchyma. Smoking was associated inversely with the adaptive immune response and directly with innate immunity. We observed a prominent adaptive immune response in squamous cell carcinomas (SCC) but greater innate immune responses in adenocarcinomas and large cell carcinomas. Cox model analysis showed a low risk of death for smoking <41 packs/year, N-0 tambour stage, squamous carcinoma, CD4(+) > 16.81% and macrophages/monocytes >4.5%. Collectively, the data indicate that in NSCLC there is not a substantive local immune cell infiltrate within the tumour. Conclusion: Although immune cell infiltration is limited in NSCLC it appears to have an impact on prognosis and this may be of relevance for new immunotherapeutic approaches.

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The aim was to analyze the protein expression of apoptotic genes caspase-3, caspase-8 and bcl-2 with the immunohistochemistry technique, correlating with tumor grade (I, II and III) and with the patient survival in order to understand the basic mechanism of tumoral transformation. The immunohistochemistry reactions on 50 samples of squamous cell carcinoma were carried out with the avidin-biotin immunoperoxidase method and antigen recovery. The analyses were made using the graduation method "in crosses" (0 to 4 crosses - no stain to more than 75% of positives cells) and in categories (low, intermediate, high) of the cytoplasm immunoreactivity of the epidermoid penile carcinoma cells. It was observed a statistically significant difference when the expression of caspase-3 were compared with the grades land II of the tumor (p=0.0010) and when comparing the patient survival with the grades I and II of the tumor (p=0.0212). The protein bcl-2 was more expressed than caspase-3 and caspase-8 proteins, suggesting that the apoptotic rate in this carcinoma is low. The higher expression of the anti-apoptotic protein bcl-2 suggests a higher preservation of the tumoral cells.

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The pineal gland, a circumventricular organ, plays an integrative role in defense responses. The injury-induced suppression of the pineal gland hormone, melatonin, which is triggered by darkness, allows the mounting of innate immune responses. We have previously shown that cultured pineal glands, which express toll-like receptor 4 (TLR4) and tumor necrosis factor receptor 1 (TNFR1), produce TNF when challenged with lipopolysaccharide (LPS). Here our aim was to evaluate which cells present in the pineal gland, astrocytes, microglia or pinealocytes produced TNF, in order to understand the interaction between pineal activity, melatonin production and immune function. Cultured pineal glands or pinealocytes were stimulated with LPS. TNF content was measured using an enzyme-linked immunosorbent assay. TLR4 and TNFR1 expression were analyzed by confocal microscopy. Microglial morphology was analyzed by immunohistochemistry. In the present study, we show that although the main cell types of the pineal gland (pinealocytes, astrocytes and microglia) express TLR4, the production of TNF induced by LPS is mediated by microglia. This effect is due to activation of the nuclear factor kappa B (NF-kB) pathway. In addition, we observed that LPS activates microglia and modulates the expression of TNFR1 in pinealocytes. As TNF has been shown to amplify and prolong inflammatory responses, its production by pineal microglia suggests a glia-pinealocyte network that regulates melatonin output. The current study demonstrates the molecular and cellular basis for understanding how melatonin synthesis is regulated during an innate immune response, thus our results reinforce the role of the pineal gland as sensor of immune status.

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Recent research with several species of nonhuman primates suggests sophisticated motor-planning abilities observed in human adults may be ubiquitous among primates. However, there is considerable variability in the extent to which these abilities are expressed across primate species. In the present experiment, we explore whether the variability in the expression of anticipatory motor-planning abilities may be attributed to cognitive differences (such as tool use abilities) or whether they may be due to the consequences of morphological differences (such as being able to deploy a precision grasp). We compared two species of New World monkeys that differ in their tool use abilities and manual dexterity: squirrel monkeys, Saimiri sciureus (less dexterous with little evidence for tool use) and tufted capuchins, Sapajus apella (more dexterous and known tool users). The monkeys were presented with baited cups in an untrained food extraction task. Consistent with the morphological constraint hypothesis, squirrel monkeys frequently showed second-order motor planning by inverting their grasp when picking up an inverted cup, while capuchins frequently deployed canonical upright grasping postures. Findings suggest that the lack of ability for precision grasping may elicit more consistent second-order motor planning, as the squirrel monkeys (and other species that have shown a high rate of second-order planning) have fewer means of compensating for inefficient initial postures. Thus, the interface between morphology and motor planning likely represents an important factor for understanding both the ontogenetic and phylogenetic origins of sophisticated motor-planning abilities.

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Recent research with several species of nonhuman primates suggests sophisticated motor-planning abilities observed in human adults may be ubiquitous among primates. However, there is considerable variability in the extent to which these abilities are expressed across primate species. In the present experiment, we explore whether the variability in the expression of anticipatory motor-planning abilities may be attributed to cognitive differences (such as tool use abilities) or whether they may be due to the consequences of morphological differences (such as being able to deploy a precision grasp). We compared two species of New World monkeys that differ in their tool use abilities and manual dexterity: squirrel monkeys, Saimiri sciureus (less dexterous with little evidence for tool use) and tufted capuchins, Sapajus apella (more dexterous and known tool users). The monkeys were presented with baited cups in an untrained food extraction task. Consistent with the morphological constraint hypothesis, squirrel monkeys frequently showed second-order motor planning by inverting their grasp when picking up an inverted cup, while capuchins frequently deployed canonical upright grasping postures. Findings suggest that the lack of ability for precision grasping may elicit more consistent second-order motor planning, as the squirrel monkeys (and other species that have shown a high rate of second-order planning) have fewer means of compensating for inefficient initial postures. Thus, the interface between morphology and motor planning likely represents an important factor for understanding both the ontogenetic and phylogenetic origins of sophisticated motor-planning abilities. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

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Biodegradable nanoparticles are at the forefront of drug delivery research as they provide numerous advantages over traditional drug delivery methods. An important factor affecting the ability of nanoparticles to circulate within the blood stream and interact with cells is their morphology. In this study a novel processing method, confined impinging jet mixing, was used to form poly (lactic acid) nanoparticles through a solvent-diffusion process with Pluronic F-127 being used as a stabilizing agent. This study focused on the effects of Reynolds number (flow rate), surfactant presence in mixing, and polymer concentration on the morphology of poly (lactic acid) nanoparticles. In addition to looking at the parameters affecting poly (lactic acid) morphology, this study attempted to improve nanoparticle isolation and purification methods to increase nanoparticle yield and ensure specific morphologies were not being excluded during isolation and purification. The isolation and purification methods used in this study were centrifugation and a stir cell. This study successfully produced particles having pyramidal and cubic morphologies. Despite successful production of these morphologies the yield of non-spherical particles was very low, additionally great variability existed between redundant trails. Surfactant was determined to be very important for the stabilization of nanoparticles in solution but appears to be unnecessary for the formation of nanoparticles. Isolation and purification methods that produce a high yield of surfactant free particles have still not been perfected and additional testing will be necessary for improvement.¿

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The receptor tyrosine kinase MET is a prime target in clinical oncology due to its aberrant activation and involvement in the pathogenesis of a broad spectrum of malignancies. Similar to other targeted kinases, primary and secondary mutations seem to represent an important resistance mechanism to MET inhibitors. Here, we report the biologic activity of a novel MET inhibitor, EMD1214063, on cells that ectopically express the mutated MET variants M1268T, Y1248H, H1112Y, L1213V, H1112L, V1110I, V1206L, and V1238I. Our results demonstrate a dose-dependent decrease in MET autophosphorylation in response to EMD1214063 in five out of the eight cell lines (IC50 2-43nM). Blockade of MET by EMD1214063 was accompanied by a reduced activation of downstream effectors in cells expressing EMD1214063-sensitive mutants. In all sensitive mutant-expressing lines, EMD1214063 altered cell cycle distribution, primarily with an increase in G1 phase. EMD1214063 strongly influenced MET-driven biological functions, such as cellular morphology, MET-dependent cell motility and anchorage-independent growth. To assess the in vivo efficacy of EMD1214063, we used a xenograft tumor model in immunocompromised mice bearing NIH3T3 cells expressing sensitive and resistant MET mutated variants. Animals were randomized for the treatment with EMD1214063 (50mg/kg/day) or vehicle only. Remarkably, five days of EMD1214063 treatment resulted in a complete regression of the sensitive H1112L-derived tumors, while tumor growth remained unaffected in mice with L1213V tumors and in vehicle-treated animals. Collectively, the current data identifies EMD1214063 as a potent MET small molecule inhibitor with selective activity towards mutated MET variants.

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Regulation of colonic epithelial cell proliferation and differentiation remains poorly understood due to the inability to design a model system which recapitulates these processes. Currently, properties of "differentiation" are studied in colon adenocarcinoma cell lines which can be induced to express some, but not all of the phenotypes of normal cells. In this thesis, the DiFi human colon adenocarcinoma cell line is utilized as an in vitro model system in which to study mucin production. In response to treatment with tumor necrosis factor-alpha, DiFi cells acquire some properties of mucin-producing goblet cells including altered morphology, increased reactivity to wheat germ agglutinin, and increased mucin production as determined by RNA expression as well as reactivity with the MUC-1 antibodies, HMFG-1 and SM-3. Thus, TNF-treated DiFi cells represent one of the few in vitro systems in which mucin expression can be induced.^ DiFi cells express an activated pp60$\sp{{\rm c}-src},$ as do most colon adenocarcinomas and derived cell lines, as well as an amplified epidermal growth factor (EGF) receptor. To assess potential changes in these enzymes during induction of differentiation characteristics, potential changes in the levels and activities of these enzymes were examined. For pp60$\sp{{\rm c}-src},$ no changes were observed in protein levels, specific activity of the kinase, cellular localization, or phosphorylation pattern as determined by Staphylococcus aureus V8 protease partial proteolytic mapping after induction of goblet cell-like phenotypic changes. These results suggest that pp60$\sp{{\rm c}-src}$ is regulated differentially in goblet cells than in absorptive cells, as down-modulation of pp60$\sp{{\rm c}-src}$ kinase occurs in the latter. Therefore, effects on pp60$\sp{{\rm c}-src}$ may be critical in colon regulation, and may be important in generating the various colonic epithelial cell types.^ In contrast to pp60$\sp{{\rm c}-src},$ EGF receptor tyrosine kinase activity decreased ($<$5-fold) after TNF treatment and at the time in which morphologic changes were observed. Similar decreases in tyrosine phosphorylation of EGF receptor were observed as assessed by immunoblotting with an anti-phosphotyrosine antibody. In addition, ($\sp{125}$I) -EGF cell surface binding was reduced approximately 3-fold following TNF treatment with a concomitant reduction in receptor affinity ($<$2-fold). These results suggest that modulation of EGF receptor may be important in goblet cell differentiation. In contrast, other published studies have demonstrated that increases in EGF receptor mRNA and in ($\sp{125}$I) -EGF binding accompany differentiation toward the absorptive cell phenotype. Therefore, differential regulation of both EGF receptor and pp60$\sp{{\rm c}-src}$ occur along the goblet cell and absorptive cell differentiation pathways. Thus, my results suggest that TNF-treated DiFi cells represent a unique system in which to study distinct patterns of regulation of pp60$\sp{{\rm c}-src}$ and EGF receptor in colonic cells, and to determine if increased MUC-1 expression is an early event in goblet cell differentiation. ^

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Vascular endothelial growth factor and its receptors, FLK1/KDR and FLT1, are key regulators of angiogenesis. Unlike FLK1/KDR, the role of FLT1 has remained elusive. FLT1 is produced as soluble (sFLT1) and full-length isoforms. Here, we show that pericytes from multiple tissues produce sFLT1. To define the biologic role of sFLT1, we chose the glomerular microvasculature as a model system. Deletion of Flt1 from specialized glomerular pericytes, known as podocytes, causes reorganization of their cytoskeleton with massive proteinuria and kidney failure, characteristic features of nephrotic syndrome in humans. The kinase-deficient allele of Flt1 rescues this phenotype, demonstrating dispensability of the full-length isoform. Using cell imaging, proteomics, and lipidomics, we show that sFLT1 binds to the glycosphingolipid GM3 in lipid rafts on the surface of podocytes, promoting adhesion and rapid actin reorganization. sFLT1 also regulates pericyte function in vessels outside of the kidney. Our findings demonstrate an autocrine function for sFLT1 to control pericyte behavior.

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BACKGROUND Finding the right balance between tibial coverage and minimal implant overhang is an important factor in TKA. Another significant cause of failure is component malrotation. METHODS An average master shape of the proximal tibia at TKA resection level was calculated using fine slice computed tomographies of 117 cadaveric knees. To find out whether alternate implant contours would be necessary depending on the patient's body size, we established five subgroups to compare. CAD-Analysis was performed to simulate the overhang produced after ±4°/±7°/±10° rotation. RESULTS A master shape for the tibial resection cut (with a 5° posterior slope, 7 mm under lateral joint line) could be determined. Neither left vs. right knee joint, nor male vs. female nor the size subdivision appears to alter the calculated master shape significantly. The optimized shape allowing for ±4° of rotational freedom was found to be the best variant. CONCLUSIONS Valid methods have been obtained to design a two-dimensional average shape of the tibial plateau. The modifications described in this study might come in useful, when designing future implant designs. CLINICAL RELEVANCE An optimized fit at the tibial plateau and lower rates of component malrotation may result in better outcomes after TKA.

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MicroRNA miR-199a-5p impairs tight junction formation leading to increased urothelial permeability in bladder pain syndrome. Now using transcriptome analysis in urothelial TEU-2 cells we implicate it in the regulation of cell cycle, cytoskeleton remodeling, TGF and Wnt signaling pathways. MiR-199a-5p is highly expressed in the smooth muscle layer of the bladder and we altered its levels in bladder smooth muscle cells (SMC) to validate the pathway analysis. Inhibition of miR-199a-5p with antimiR increased SMC proliferation, reduced cell size and up-regulated miR-199a-5p targets, including Wnt2. Overexpression of Wnt2 protein or treating SMCs with recombinant Wnt2 closely mimicked the miR-199a-5p inhibition, whereas down-regulation of Wnt2 in antimiR-expressing SMCs with shRNA restored cell phenotype and proliferation rates. Overexpression of miR-199a-5p in the bladder SMCs significantly increased cell size and up-regulated SM22, SM alpha-actin and SM myosin heavy chain mRNA and protein levels. These changes, as well as increased expression of ACTG2, TGFB1I1, and CDKN1A were mediated by up-regulation of smooth muscle-specific transcriptional activator myocardin at mRNA and protein levels. Myocardin-related transcription factor (MRTF-A) downstream targets Id3 and MYL9 were also induced. Up-regulation of myocardin was accompanied by down-regulation of Wnt-dependent inhibitory Kruppel-like transcription factor 4 (KLF4) in miR-199a-5p overexpressing cells. In contrast, KLF4 was induced in antimiR-expressing cells following the activation of Wnt2 signaling, leading to repression of myocardin-dependent genes. MiR-199a-5p plays a critical role in the Wnt2-mediated regulation of proliferative and differentiation processes in the smooth muscle and may behave as a key modulator of smooth muscle hypertrophy, relevant for organ remodeling.

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Retinal vein occlusion is a leading cause of visual impairment. Experimental models of this condition based on laser photocoagulation of retinal veins have been described and extensively exploited in mammals and larger rodents such as the rat. However, few reports exist on the use of this paradigm in the mouse. The objective of this study was to investigate a model of branch and central retinal vein occlusion in the mouse and characterize in vivo longitudinal retinal morphology alterations using spectral domain optical coherence tomography. Retinal veins were experimentally occluded using laser photocoagulation after intravenous application of Rose Bengal, a photo-activator dye enhancing thrombus formation. Depending on the number of veins occluded, variable amounts of capillary dropout were seen on fluorescein angiography. Vascular endothelial growth factor levels were markedly elevated early and peaked at day one. Retinal thickness measurements with spectral domain optical coherence tomography showed significant swelling (p<0.001) compared to baseline, followed by gradual thinning plateauing two weeks after the experimental intervention (p<0.001). Histological findings at day seven correlated with spectral domain optical coherence tomography imaging. The inner layers were predominantly affected by degeneration with the outer nuclear layer and the photoreceptor outer segments largely preserved. The application of this retinal vein occlusion model in the mouse carries several advantages over its use in other larger species, such as access to a vast range of genetically modified animals. Retinal changes after experimental retinal vein occlusion in this mouse model can be non-invasively quantified by spectral domain optical coherence tomography, and may be used to monitor effects of potential therapeutic interventions.

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OBJECTIVE: Survivors of premature birth suffer from long term disabilities. Synthetic PreImplantation Factor (sPIF*) modulates inflammatory responses and reverses neuroinflammation. Proteinkinase A (PKA) and protein kinase C (PKC) are crucial signaling molecules. PKA up-regulates IL-10 and brain-derived neurotrophic factor (BDNF) expression, which exert neuroprotective effects. Anti-apoptotic phosphorylation of Bad is mediated by PKA. PKC phosphorylates GAP-43, a marker for neuronal plasticity and structural recovery. We explored sPIF protective role in neuronal (N2a) cells and in a rat model of encephalopathy of prematurity. *proprietary. STUDY DESIGN: Cells were subjected to LPS and treated with sPIF or scrambled sPIF. Neonatal rats (postnatal day 3: P3) were subjected to LPS, ligation of carotid artery, and hypoxia (8% O2, 65min; n¼ 30). sPIF (0.75mg/kg twice daily) was injected (P6-13) and brains harvested at P13. sPIF’s potential and mechanisms were evaluated using immunohistochemistry, ELISA, Western Blot, and qRT-PCR. Data were analyzed using two-tailed Student’s t-test. P<0.05 wasconsidered statistically significant. RESULTS: In vitro sPIF increased PKA/PKC activity in time dependent manner (Fig. 1A). sPIF induced higher IL-10, BDNF, and GAP-43 and lower CASP3, BAD, and TNF-a mRNA levels (Fig. 1B,C). sPIF increased pGap-43/Gap-43 and decreased pBad/Bad ratio while decreasing Bad (Fig. 1 D,E). In brain tissue sPIF treatment resulted in rescued neuronal number (NeuN positive cells) and reduced apoptosis (Casp-3 positive cells) with decreased glial (Iba-1 positive cells) activation (Fig. 2A,B). The Iba-1 morphology changed from predominantly amoeboid to ramified state. Additionally sPIF increased IL-10 mRNA levels (Fig. 2C) and pGap-43/Gap-43 ratio (Fig. 2D). CONCLUSION: sPIF modulates PKA/PKC pathways reducing apoptosis and inflammatory responses while increasing neuronal plasticity and survival. The identified PKA/PKC regulatory axis strengthens the potential of sPIF in reducing the burden of prematurity.