969 resultados para Magnification Factors, Metodo Alpha, torsione


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

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The purpose of this study was to review the literature regarding the action of the cytokines interleukin 10 (IL-10) and tumor necrosis factor-alpha (TNF-α) in pregnancy and to emphasize the factors that are of interest to clinical obstetrics. The literature highlights several actions of IL-10 and TNF-α during pregnancy. The actions of these cytokines seem to be antagonistic and dependent on the balance between them, which is orchestrated by the specific immunosuppressive action of IL-10. TNF-α has a characteristic inflammatory action, and it is an additional diabetogenic factor in pregnancy. The loss of the control of the production of these cytokines, with increase of TNF-α, is related to the risk for developing obstetric complications, particularly recurrent fetal loss, gestational diabetes mellitus, hypertensive syndromes, and fetal growth restriction. However, study results are controversial and are not clearly defined. These issues are attributed to the heterogeneity of the studies, particularly regarding their sample sizes and sources, the evaluation methods, and the multiplicity of factors and conditions that influence cytokine production. These questions are fundamental and should be addressed in future investigations to obtain more consistent results that can be applied to obstetric practice.

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Interferon-alpha (IFN- α ), a type I IFN, is a protein with antiviral, antiproliferative, and immunoregulatory activities, widely used in the treatment of several types of cancers as well as hepatitis B and C. Decrease of libido and erectile dysfunction are commonly reported by male patients during treatment of chronic hepatitis C with IFN- α . However, IFN therapy-associated underlying factors attributed to sexual dysfunction are still not well defined. Currently, there are few studies investigating the effects of IFN on male reproductive system functions. Given that, the aim of the present investigation was to examine effects of subchronic exposure to IFN- α (5 × 10(4) U/kg and 10 × 10(4) U/kg, 30 d) on serum hormones, sperm parameters, fertility, and testicular and epididymal hystopathology and morphometry in adult male Wistar rats. None of the evaluated parameters was markedly altered by IFN- α . Thus, our results suggest that exposure to IFN- α , in this experimental design, did not adversely affect sperm quality and fertile capacity of male rats.

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

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Different types of shed vesicles as, for example, exosomes, plasma-membrane-derived vesicles or microparticles, are the focus of intense research in view of their potential role in cell cell communication and under the perspective that they might be good tools for immunotherapy, vaccination or diagnostic purposes. This review discusses ways employed by pathogenic trypanosomatids to interact with the host by shedding vesicles that contain molecules important for the establishment of infection, as opposed to previous beliefs considering them as a waste of cellular metabolism. Trypanosomatids are compared with Apicomplexa, which circulate parasite antigens bound to vesicles shed by host cells. The knowledge of the origin and chemical composition of these different vesicles might lead to the understanding of the mechanisms that determine their biological function. (C) 2012 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

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Background: Zinc-alpha 2-glycoprotein (ZAG) is a lipid mobilizing factor. Its anti-inflammatory action and expression pattern suggest that ZAG could act by protecting against the obesity-associated disorders. In hemodialysis (HD) patients, ZAG levels were described to be elevated but its effects on markers of inflammation and LDL oxidation are still unclear. We investigated the relationship between ZAG and markers of systemic inflammation and LDL atherogenic modification profile in HD patients. Methods: Forty-three patients regularly on HD were studied and compared to 20 healthy subjects. Plasma ZAG, adiponectin, electronegative LDL [LDL(-)], an atherosclerotic negatively charged LDL subtraction, and anti-LDL(-) autoantibodies levels were measured by ELISA. Markers of inflammation and atherogenic cell recruitment (TNF-alpha, interleukin-6, VCAM-1, ICAM-1, MCP-1 and PAI-1) were also determined. Results: Inflammatory markers and atherogenic cell recruitment were higher in HD patients when compared to healthy subjects. ZAG levels were also higher in HD patients (151.5 +/- 50.1 mg/l vs 54.6 +/- 23.0 mg/l; p<0.0001) and its levels were negatively correlated with TNF-alpha (r= -0.39; p = 0.001) and VCAM-1 (r= -0.52; p<0.0001) and, positively correlated with anti-LDL(-) autoantibodies (r = 038; p = 0.016). On multivariate analyses, plasma ZAG levels were independently associated with VCAM-1 (p = 0.01). Conclusion: ZAG is inversely associated with markers of pro-atherogenic factors linked to systemic inflammation and oxidative stress. Thus, this adipokine may constitute a novel marker of a favorable metabolic profile regarding cardiovascular risk factors in HD population. (C) 2011 Elsevier B.V. All rights reserved.

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Background: Thyroid hormones (THs) are known to regulate protein synthesis by acting at the transcriptional level and inducing the expression of many genes. However, little is known about their role in protein expression at the post-transcriptional level, even though studies have shown enhancement of protein synthesis associated with mTOR/p70S6K activation after triiodo-l-thyronine (T3) administration. On the other hand, the effects of TH on translation initiation and polypeptidic chain elongation factors, being essential for activating protein synthesis, have been poorly explored. Therefore, considering that preliminary studies from our laboratory have demonstrated an increase in insulin content in INS-1E cells in response to T3 treatment, the aim of the present study was to investigate if proteins of translational nature might be involved in this effect. Methods: INS-1E cells were maintained in the presence or absence of T3 (10(-6) or 10(-8) M) for 12 hours. Thereafter, insulin concentration in the culture medium was determined by radioimmunoassay, and the cells were processed for Western blot detection of insulin, eukaryotic initiation factor 2 (eIF2), p-eIF2, eIF5A, EF1A, eIF4E binding protein (4E-BP), p-4E-BP, p70S6K, and p-p70S6K. Results: It was found that, in parallel with increased insulin generation, T3 induced p70S6K phosphorylation and the expression of the translational factors eIF2, eIF5A, and eukaryotic elongation factor 1 alpha (eEF1A). In contrast, total and phosphorylated 4E-BP, as well as total p70S6K and p-eIF2 content, remained unchanged after T3 treatment. Conclusions: Considering that (i) p70S6K induces S6 phosphorylation of the 40S ribosomal subunit, an essential condition for protein synthesis; (ii) eIF2 is essential for the initiation of messenger RNA translation process; and (iii) eIF5A and eEF1A play a central role in the elongation of the polypeptidic chain during the transcripts decoding, the data presented here lead us to suppose that a part of T3-induced insulin expression in INS-1E cells depends on the protein synthesis activation at the post-transcriptional level, as these proteins of the translational machinery were shown to be regulated by T3.

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Background. Intestinal ischemia and reperfusion (I/R) is a documented cause of acute lung injury (ALI) and systemic inflammation. We previously reported that obstruction of thoracic lymphatic flow during intestinal I/R blunts pulmonary neutrophil recruitment and microvascular injury and decreases the systemic levels of tumor necrosis factor. Here, we consider the existence of a gut-lung axis promoting the induction of systemic inflammation, whereby drained intestinal lymph stimulates lung expression of adhesion molecules and matrix components and generation of inflammatory mediators. Material and Methods. Upon administration of anesthesia, male Wistar rats were subjected to occlusion of the superior mesenteric artery for 45 min, followed by 2 h of intestinal reperfusion (I/R); groups of rats were subjected to I/R with or without thoracic lymphatic duct ligation immediately before the procedure. The non-manipulated rats were used to investigate basal parameters. Results. Obstruction of thoracic lymphatic flow before intestinal I/R decreased the ability of cultured lung tissue explants to release IL-1 beta, IL-10, and VEGF. In contrast, lymphatic obstruction normalized the elevated lung expression of PECAM-1 caused by intestinal I/R. On the other hand, lung E-selectin expression was significantly reduced, whereas fibronectin expression and collagen synthesis were not affected. Lymph levels of LTB4 and TXB2 were found to be significantly increased. Conclusions. These data suggest that lymph factors drained from the intestine during ischemic trauma stimulate the lung to generate inflammatory mediators and alter the expression of adhesion molecules. Disturbances in lung homeostasis mediated by lymph might contribute to the spread of inflammatory processes, thereby accounting for the systemic inflammation induced by intestinal I/R. (C) 2012 Elsevier Inc. All rights reserved.

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Objective. The objective of this preliminary study was to evaluate the expression of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs) and growth factors in keratocystic odontogenic tumors (KOTs). Study Design. The expression of MMPs, TIMPs, growth factors, and the extracellular signal-regulated kinase (ERK) 1/2 signaling pathway were assessed by immunohistochemistry in 15 cases of KOT and 4 cases of calcifying cystic odontogenic tumor (CCOT). Results. KOT samples expressed significantly higher amounts of MMPs, TIMPs, growth factors, epidermal growth factor receptor (EGFR), and ERK compared with CCOT samples, with the exception of MMP-2 and TIMP-1. Conclusions. MMP-9, TIMP-2, EGF and transforming growth factor alpha act together and likely regulate the proliferation and aggressiveness of KOT. ERK-1/2 serves as the transducer of signals generated by these proteins, which signal through the common receptor, EGFR. This process may be related to the increased proliferation and aggressiveness observed in KOT. (Oral Surg Oral Med Oral Pathol Oral Radiol 2012;114:487-496)

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Cancer cachexia is a multifaceted syndrome whose aetiology is extremely complex and is directly related to poor patient prognosis and survival. Changes in lipid metabolism in cancer cachexia result in marked reduction of total fat mass, increased lipolysis, total oxidation of fatty acids, hyperlipidaemia, hypertriglyceridaemia, and hypercholesterolaemia. These changes are believed to be induced by inflammatory mediators, such as tumour necrosis factor-alpha (TNF-alpha) and other factors. Attention has recently been drawn to the current theory that cachexia is a chronic inflammatory state, mainly caused by the host's reaction to the tumour. Changes in expression of numerous inflammatory mediators, notably in white adipose tissue (WAT), may trigger several changes in WAT homeostasis. The inhibition of adipocyte differentiation by PPAR gamma is paralleled by the appearance of smaller adipocytes, which may partially account for the inhibitory effect of PPAR gamma on inflammatory gene expression. Furthermore, inflammatory modulation and/or inhibition seems to be dependent on the IKK/NF-kappa B pathway, suggesting that a possible interaction between NF-kappa B and PPAR gamma is required to modulate WAT inflammation induced by cancer cachexia. In this article, current literature on the possible mechanisms of NF-kappa B and PPAR gamma regulation of WAT cells during cancer cachexia are discussed. This review aims to assess the role of a possible interaction between NF-kappa B and PPAR gamma in the setting of cancer cachexia as well as its significant role as a potential modulator of chronic inflammation that could be explored therapeutically. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.

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Bestimmte humane Papillomviren sind an der Entstehung von Zervixkarzinomen beteiligt. In dieser Arbeit wird gezeigt, daß maligne HPV-positive Zellen ihre Fähigkeit zur Induktion von endogenem IFN-beta nach TNF-alpha verloren haben. Durch Infektion mit Encephalomyocarditis Virus (EMCV) oder Vesicular Stomatitis Virus (VSV) wurde die Induzierbarkeit des endogenen IFN-beta durch TNF-alpha in nicht-tumorigenen Zellen bestätigt. Alle malignen Zellinien zeigten eine intakte IFN Signaltransduktion, wenn Typ I oder Typ II Interferone exogen supplementiert wurden. Dies zeigt, daß in tumorigenen Zervixkarzinomzellen die Kommunikation zwischen TNF-alpha und IFN-beta

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AD is the most common age related neurodegenerative disease in the industrialized world. Clinically AD is defined as a progressing decline of cognitive functions. Neuropathologically, AD is characterized by the aggregation of b-amyloid (Ab) peptide in the form of extracellular senile plaques, and hyperphosphorlylated tau protein in the form of intracellular neurofibrillary tangles. These neuropathological hallmarks are often accompanied by abundant microvascular damage and pronounced inflammation of the affected brain regions. In this thesis we investigated several aspects of AD focusing on the genetic aspect. We confirmed that Alpha 1 antichymotrypsin (ACT), an acute phase protein, was associated to AD subjects, being plasma levels higher in AD cases than controls. In addition, in a GWA study we demonstrated that two different gene, Clusterin and CR1 were strongly associated to AD. A single gene association not explain such a complex disease like AD. The goal should be to created a network of genetic, phenotypic and clinical data associated to AD. We used a new algorithm, the ANNs, aimed to map variables and search for connectivity among variables. We found specific variables associated to AD like cholesterol levels, the presence of variation in HMGCR enzyme and the age. Other factors such as the BMI, the amount of HDL and blood folate levels were also associated with AD. Pathogen infections, above all viral infections, have been previously associated to AD. The hypothesis suggests that virus and in particular herpes virus could enter the brain when an individual becomes older, perhaps because of a decline in the immune system. Our new hypothesis is that the presence of SNPs in our GWA gene study results in a genetic signature that might affect individual brain susceptibility to infection by herpes virus family during aging.

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Background: Delirium is defined as an acute disorder of attention and cognition. Delirium is common in hospitalized elderly patient and is associated with increased morbidity, length of stay and patient care costs. Although Delirium can develop at any time during hospitalization, it typically presents early in the post-operative period (Post-Operative Delirium, POD) in the surgery context. The molecular mechanism and possible genetics basis of POD onset are not known, as well as all the risk factors are not completely defined. Our hypothesis is that genetic risk factor involving the inflammatory response could have possible effects on the immunoneuroendocrine system. Moreover, our previous data (inflamm-aging) suggest that aging is associated with an increase of inflammatory status, favouring age-related diseases such as neurodegenerative diseases, frailty, depression among other. Some pro-inflammatory or anti-inflammatory cytokines, seem to play a crucial role in increasing the inflammatory status and in the communication and regulation of immunoneuroendocrine system. Objective: this study evaluated the incidence of POD in elderly patients undergoing general surgery, clinical/physical and psychological risk factors of POD insurgency and investigated inflammatory and genetic risk factors. Moreover, this study evaluated the consequence of POD in terms of institutionalization, development of permanent cognitive dysfunction or dementia and mortality Methods: patients aged over 65 admitted for surgery at the Urgency Unit of S.Orsola-Malpighi Hospital were eligible for this case–control study. Risk factors significantly associated with POD in univariate analysis were entered into multivariate analysis to establish those independently associated with POD. Preoperative plasma level of 9 inflammatory markers were measured in 42 control subjects and 43 subjects who developed POD. Functional polymorphisms of IL-1 α , IL-2, IL-6, IL-8, IL-10 and TNF-alpha cytokine genes were determined in 176 control subjects and 27 POD subjects. Results: A total of 351 patients were enrolled in the study. The incidence of POD was 13•2 %. Independent variables associated with POD were: age, co-morbidity, preoperative cognitive impairment, glucose abnormalities. Median length of hospital stay was 21 days for patients with POD versus 8 days for control patients (P < 0•001). The hospital mortality rate was 19 and 8•4 % respectively (P = 0•021) and mortality rate after 1 year was also higher in POD (P= 0.0001). The baseline of IL-6 concentration was higher in POD patients than patients without POD, whereas IL-2 was lower in POD patients compared to patients without POD. In a multivariate analysis only IL-6 remained associated with POD. Moreover IL-6, IL-8 and IL-2 are associated with co-morbidity, intra-hospital mortality, compromised functional status and emergency admission. No significant differences in genotype distribution were found between POD subjects and controls for any SNP analyzed in this study. Conclusion: In this study we found older age, comorbidity, cognitive impairment, glucose abnormalities and baseline of IL-6 as independent risk factors for the development of POD. IL-6 could be proposed as marker of a trait that is associated with an increased risk of delirium; i.e. raised premorbid IL-6 level predict for the development of delirium.

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Staphylococcus aureus alpha-hemolysin was the first bacterial toxin recognized to form pores in the plasma membrane of eukaryotic cells. It is secreted as a water-soluble monomer that upon contact with target membranes forms an amphiphatic heptameric beta-barrel which perforates the bilayer. As a consequence, red cells undergo colloidosmotic lyses, while some nucleated cells may succumb to necrosis or programmed cell death. However, most cells are capable of repairing a limited number of membrane lesions, and then respond with productive transcriptional activation of NF-kB. In the present study, by using microarray and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), data from a previously performed serial analysis of gene expression (SAGE) were extended and verified, revealing that immediate early genes (IEGs) such as c-fos, c-jun and egr-1 are strongly induced at 2-8 h after transient toxin treatment. Activating protein 1 (AP-1: c-Fos, c-Jun) binding activity was increased accordingly. As IEGs are activated by growth factors, these findings led to the discovery that -toxin promotes cell cycle progression of perforated cells in an EGFR-dependent fashion. Although the amount of c-fos mRNA rose rapidly after toxin treatment, c-Fos protein expression was observed only after a lag of about 3 h. Since translation consumes much ATP, which transiently drops after transient membrane perforation, the suspicion arised that membrane-perforation caused global, but temporary downregulation of translation. In fact, eIF2α became heavily phosphorylated minutes after cells had been confronted with the toxin, resulting in shutdown of protein synthesis before cellular ATP levels reached the nadir. GCN2 emerged as a candidate eIF2α kinase, since its expression rapidly increased in toxin-treated cells. Two hours after toxin treatment, GADD34 transcripts, encoding a protein that targets the catalytic subunit of protein phosphatase 1 (PP1) to the endoplasmic reticulum, were overexpressed. This was followed by dephosphorylation of eIF2α and resumption of protein synthesis. Addition of tautomycetin, a specific inhibitor of PP1, led to marked hyperphosphorylation of eIF2α and significantly reduced the drop of ATP-levels in toxin-treated cells. A novel link between two major stress-induced signalling pathways emerged when it was found that both translational arrest and restart were under the control of stress-activated protein kinase (SAPK) p38. The data provide an explanation for the indispensible role of p38 for defence against the archetypal threat of membrane perforation by agents that produce small transmembrane-pores.

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Hypoxia-inducible factor-1 alpha (HIF-1α) plays a critical role in survival and is associated with poor prognosis in solid tumors. The role of HIF-1α in multiple myeloma is not completely known. In the present study, we explored the effect of EZN2968, an locked nucleic acid antisense oligonucleotide against HIF-1α, as a molecular target in MM. A panel of MM cell lines and primary samples from MM patients were cultured in vitro in the presence of EZN2968 . Under normoxia culture condition, HIF-1α mRNA and protein expression was detectable in all MM cell lines and in CD138+ cells from newly diagnosed MM patients samples. Significant up-regulation of HIF-1α protein expression was observed after incubation with IL6 or IGF-I, confirming that HIF-1α can be further induced by biological stimuli. EZN2968 efficiently induces a selective and stable down-modulation of HIF-1α and decreased the secretion of VEGF released by MM cell. Treatment with EZN2968 gave rise to a progressive accumulation of cells in the S and subG0 phase. The analysis of p21, a cyclin-dependent kinase inhibitors controlling cell cycle check point, shows upregulation of protein levels. These results suggest that HIF-1α inhibition is sufficient for cell cycle arrest in normoxia, and for inducing an apoptotic pathways.. In the presence of bone marrow microenvironment, HIF-1α inhibition blocks MAPK kinase pathway and secretion of pro-surviaval cytokines ( IL6,VEGF,IL8) In this study we provide evidence that HIF-1α, even in the absence of hypoxia signal, is expressed in MM plasma cells and further inducible by bone marrow milieu stimuli; moreover its inhibition is sufficient to induce a permanent cell cycle arrest. Our data support the hypothesis that HIF-1α inhibition may suppress tumor growth by preventing proliferation of plasma cells through p21 activation and blocking pro-survival stimuli from bone marrow microenvironment.