383 resultados para Nicolás Factor Beato, 1520-1583-Retrats-Gravat


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HYPOTHESIS: Recent evidence indicates that tumor response rates after isolated limb perfusion (ILP) are improved when tumor necrosis factor (TNF) is added to the locoregional perfusion of high doses of chemotherapy. Other factors, related to the patient or the ILP procedure, may interfere with the specific role of TNF in the early hemodynamic response after ILP with TNF and high-dose chemotherapy. DESIGN: Case-control study. SETTING: Tertiary care university hospital. PATIENTS: Thirty-eight patients with a locoregionally advanced tumor of a limb treated by ILP with TNF and high-dose chemotherapy (TNF group) were compared with 31 similar patients treated by ILP with high-dose chemotherapy alone (non-TNF group). INTERVENTIONS: Swan-Ganz catheter hemodynamic recordings, patients' treatment data collection, and TNF and interleukin 6 plasma level measurements at regular intervals during the first 36 hours following ILP. MAIN OUTCOME MEASURES: Hemodynamic profile and total fluid and catecholamine administration. RESULTS: In the TNF group, significant changes were observed (P<.006): the mean arterial pressure and the systemic vascular resistance index decreased, and the temperature, heart rate, and cardiac index increased. These hemodynamic alterations started when the ILP tourniquet was released (ie, when or shortly after the systemic TNF levels were the highest). The minimal mean arterial pressure, the minimal systemic vascular resistance index, the maximal cardiac index, the intensive care unit stay, and the interleukin 6 maximal systemic levels were significantly (P<.001 for all) correlated to the log(10) of the systemic TNF level. In the non-TNF group, only a brief decrease in the blood pressure following tourniquet release and an increase in the temperature and in the heart rate were statistically significant (P<.006). Despite significantly more fluid and catecholamine administration in the TNF group, the mean arterial pressure and the systemic vascular resistance index were significantly (P<.001) lower than in the non-TNF group. CONCLUSIONS: Release of the tourniquet induces a blood pressure decrease that lasts less than 1 hour in the absence of TNF and that is distinct from the septic shock-like hemodynamic profile following TNF administration. The systemic TNF levels are correlated to this hemodynamic response, which can be observed even at low TNF levels.

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The purpose of this ex post facto study is to analyze the personality profile of outpatients who met criteria for borderline personality disorder according to the Five-Factor Model of personality. All patients (N = 52) completed the International Personality Disorder Examination (IPDE) Screening Questionnaire, the Big Five Questionnaire (BFQ), the Beck Depression Inventory (BDI), and the Beck Hopelessness Scale (BHS). The results show a high comorbidity with other DSM-IV-TR Axis II disorders, in particular with those from Cluster C. The BFQ average score indicates that the outpatients who met borderline criteria score lower than controls on all five dimensions, and especially on emotional stability. Correlations were computed between the BFQ and the IPDE scales in our sample. These results suggest that specific personality profile are linked to different comorbidity patterns. More than a half of our sample has clinically significant scores on Beck's scales. Surprisingly, depression and hopelessness are neither correlated with the borderline scale, nor have an effect in the relationship between personality and personality disorders.

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The method of instrumental variable (referred to as Mendelian randomization when the instrument is a genetic variant) has been initially developed to infer on a causal effect of a risk factor on some outcome of interest in a linear model. Adapting this method to nonlinear models, however, is known to be problematic. In this paper, we consider the simple case when the genetic instrument, the risk factor, and the outcome are all binary. We compare via simulations the usual two-stages estimate of a causal odds-ratio and its adjusted version with a recently proposed estimate in the context of a clinical trial with noncompliance. In contrast to the former two, we confirm that the latter is (under some conditions) a valid estimate of a causal odds-ratio defined in the subpopulation of compliers, and we propose its use in the context of Mendelian randomization. By analogy with a clinical trial with noncompliance, compliers are those individuals for whom the presence/absence of the risk factor X is determined by the presence/absence of the genetic variant Z (i.e., for whom we would observe X = Z whatever the alleles randomly received at conception). We also recall and illustrate the huge variability of instrumental variable estimates when the instrument is weak (i.e., with a low percentage of compliers, as is typically the case with genetic instruments for which this proportion is frequently smaller than 10%) where the inter-quartile range of our simulated estimates was up to 18 times higher compared to a conventional (e.g., intention-to-treat) approach. We thus conclude that the need to find stronger instruments is probably as important as the need to develop a methodology allowing to consistently estimate a causal odds-ratio.

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Proteins secreted from adipose tissue are increasingly recognized to play an important role in the regulation of glucose metabolism. However, much less is known about their effect on lipid metabolism. The fasting-induced adipose factor (FIAF/angiopoietin-like protein 4/peroxisome proliferator-activated receptor gamma angiopoietin-related protein) was previously identified as a target of hypolipidemic fibrate drugs and insulin-sensitizing thiazolidinediones. Using transgenic mice that mildly overexpress FIAF in peripheral tissues we show that FIAF is an extremely powerful regulator of lipid metabolism and adiposity. FIAF overexpression caused a 50% reduction in adipose tissue weight, partly by stimulating fatty acid oxidation and uncoupling in fat. In addition, FIAF overexpression increased plasma levels of triglycerides, free fatty acids, glycerol, total cholesterol, and high density lipoprotein (HDL)-cholesterol. Functional tests indicated that FIAF overexpression severely impaired plasma triglyceride clearance but had no effect on very low density lipoprotein production. The effects of FIAF overexpression were amplified by a high fat diet, resulting in markedly elevated plasma and liver triglycerides, plasma free fatty acids, and plasma glycerol levels, and impaired glucose tolerance in FIAF transgenic mice fed a high fat diet. Remarkably, in mice the full-length form of FIAF was physically associated with HDL, whereas truncated FIAF was associated with low density lipoprotein. In human both full-length and truncated FIAF were associated with HDL. The composite data suggest that via physical association with plasma lipoproteins, FIAF acts as a powerful signal from fat and other tissues to prevent fat storage and stimulate fat mobilization. Our data indicate that disturbances in FIAF signaling might be involved in dyslipidemia.

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The addition of nerve growth factor (2.5S NGF) to serum-free aggregating cell cultures of fetal rat telencephalon greatly stimulated the developmental increase in choline acetyltransferase activity. Two other neuronal enzymes, acetylcholinesterase and glutamic acid decarboxylase, showed only slightly increased activities after NGF treatment whereas the total protein content of the cultures and the activity of 2',3'- cyclic nucleotide phosphodiesterase remained unchanged. The stimulation of choline acetyltransferase was dependent on the NGF media concentrations, showing a 50% maximum effect (120% increase) at approximately 3 ng/ml (10-10 M 2.5S NGF). NGF treatments during different culture periods showed that the cholinergic neurons remained responsive for at least 19 days. The continued treatment was the most effective; however, an initial treatment for only 5 days still caused a significant stimulation of choline acetyltransferase on day 19. The observed stimulation appeared to be specific to NGF. Univalent antibody fragments (Fab) against 2.5S NGF completely abolished the NGF-dependent increase in choline acetyltransferase activity, whereas Fab fragments of control IgG were ineffective. Furthermore, angiotensin II, added in high amounts to the cultures, showed no stimulatory effect. The present results suggest that certain populations of rat brain neurons are responsive to nerve growth factor.

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Background And Objectives: Isolated limb perfusion with TNF-alpha and melphalan (TM-ILP) is a limb salvage therapy for non-resectable soft tissue sarcomas (STS) of the extremities. It is indicated for patients for whom amputation or debilitating surgery is the only alternative. It can be used either as an exclusive therapy (in palliation) or as a neo-adjuvant treatment, followed by marginal resection of tumor remnants with minimal functional impairment. Methods: Between February 1992 and March 2006, 57 TM-ILPs were performed on 51 patients with 88% high grade and 84% advanced stage tumors. Results: Mean follow-up is 38.9 months (4-159, median 22 months). Twenty-one percent patients had significant early complications, with 3 major re-operations, and 23% suffered long-lasting complications. Complete response was observed in 25%, partial response in 42%, stable disease in 14% and progressive disease in 14%. Resection of the tumor remnants was possible in 65%. A complementary treatment was necessary in 31%, mostly radiation therapy. A local recurrence was observed in 35%, after a mean of 20.3 months (2-78), and distant relapse was seen in 45%, after a mean of 13.4 months (5-196). Mean Disease-free survival was 14.9 months, and overall 5-year-survival 43.5%. Amputation rate at 5 years was 24%. Conclusions: TM-ILP is a conservative treatment with a high complications rate, but it can be successful even for the most severe STS of extremities. As a consequence the limb can be spared from amputation or debilitating surgery on the long term in about 75% of patients

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In the plant-beneficial, root-colonizing strain Pseudomonas fluorescens CHA0, the Gac/Rsm signal transduction pathway positively regulates the synthesis of biocontrol factors (mostly antifungal secondary metabolites) and contributes to oxidative stress response via the stress sigma factor RpoS. The backbone of this pathway consists of the GacS/GacA two-component system, which activates the expression of three small regulatory RNAs (RsmX, RsmY, RsmZ) and thereby counters translational repression exerted by the RsmA and RsmE proteins on target mRNAs encoding biocontrol factors. We found that the expression of typical biocontrol factors, that is, antibiotic compounds and hydrogen cyanide (involving the phlA and hcnA genes), was significantly lower at 35 degrees C than at 30 degrees C. The expression of the rpoS gene was affected in parallel. This temperature control depended on RetS, a sensor kinase acting as an antagonist of the GacS/GacA system. An additional sensor kinase, LadS, which activated the GacS/GacA system, apparently did not contribute to thermosensitivity. Mutations in gacS or gacA were epistatic to (that is, they overruled) mutations in retS or ladS for expression of the small RNAs RsmXYZ. These data are consistent with a model according to which RetS-GacS and LadS-GacS interactions shape the output of the Gac/Rsm pathway and the environmental temperature influences the RetS-GacS interaction in P. fluorescens CHA0.

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Exploratory and confirmatory factor analyses reported in the French technical manual of the WISC-IV provides evidence supporting a structure with four indices: Verbal Comprehension (VCI), Perceptual Reasoning (PRI), Working Memory (WMI), and Processing Speed (PSI). Although the WISC-IV is more attuned to contemporary theory, it is still not in total accordance with the dominant theory: the Cattell-Horn-Carroll (CHC) theory of cognitive ability. This study was designed to determine whether the French WISC-IV is better described with the four-factor solution or whether an alternative model based on the CHC theory is more appropriate. The intercorrelations matrix reported in the French technical manual was submitted to confirmatory factor analysis. A comparison of competing models suggests that a model based on the CHC theory fits the data better than the current WISC-IV structure. It appears that the French WISC-IV in fact measures six factors: crystallized intelligence (Gc), fluid intelligence (Gf), short-term memory (Gsm), processing speed (Gs), quantitative knowledge (Gq), and visual processing (Gv). We recommend that clinicians interpret the subtests of the French WISC-IV in relation to this CHC model in addition to the four indices.

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ATP, released by both neurons and glia, is an important mediator of brain intercellular communication. We find that selective activation of purinergic P2Y1 receptors (P2Y1R) in cultured astrocytes triggers glutamate release. By total internal fluorescence reflection imaging of fluorescence-labeled glutamatergic vesicles, we document that such release occurs by regulated exocytosis. The stimulus-secretion coupling mechanism involves Ca2+ release from internal stores and is controlled by additional transductive events mediated by tumor necrosis factor-alpha (TNFalpha) and prostaglandins (PG). P2Y1R activation induces release of both TNFalpha and PGE2 and blocking either one significantly reduces glutamate release. Accordingly, astrocytes from TNFalpha-deficient (TNF(-/-)) or TNF type 1 receptor-deficient (TNFR1(-/-)) mice display altered P2Y1R-dependent Ca2+ signaling and deficient glutamate release. In mixed hippocampal cultures, the P2Y1R-evoked process occurs in astrocytes but not in neurons or microglia. P2Y1R stimulation induces Ca2+ -dependent glutamate release also from acute hippocampal slices. The process in situ displays characteristics resembling those in cultured astrocytes and is distinctly different from synaptic glutamate release evoked by high K+ stimulation as follows: (a) it is sensitive to cyclooxygenase inhibitors; (b) it is deficient in preparations from TNF(-/-) and TNFR1(-/-) mice; and (c) it is inhibited by the exocytosis blocker bafilomycin A1 with a different time course. No glutamate release is evoked by P2Y1R-dependent stimulation of hippocampal synaptosomes. Taken together, our data identify the coupling of purinergic P2Y1R to glutamate exocytosis and its peculiar TNFalpha- and PG-dependent control, and we strongly suggest that this cascade operates selectively in astrocytes. The identified pathway may play physiological roles in glial-glial and glial-neuronal communication.

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OBJECTIVES: Growth retardation is a frequent complication of paediatric inflammatory bowel disease (IBD). Only a few studies report the final height of these patients, with controversial results. We compared adult height of patients with paediatric IBD with that of patients with adult-onset disease. METHODS: Height data of 675 women 19-44 years of age and 454 men 23-44 years of age obtained at inclusion in the Swiss IBD cohort study registry were grouped according to the age at diagnosis: (a) prepubertal (men≤13, women≤11 years), (b) pubertal (men 13-22, women 11-18 years) and (c) adult (men>22, women>18 years of age), and compared with each other and with healthy controls. RESULTS: Male patients with prepubertal onset of Crohn's disease (CD) had significantly lower final height (mean 172±6 cm, range 161-182) compared with men with pubertal (179±6 cm, 161-192) or adult (178±7 cm, 162-200) age at onset and the general population (178±7 cm, 142-204). Height z-scores standardized against heights of the normal population were significantly lower in all patients with a prepubertal diagnosis of CD (-0.8±0.9) compared with the other patient groups (-0.1±0.8, P<0.001). Prepubertal onset of CD emerged as a risk factor for reduced final height in patients with prepubertal CD. No difference for final height was found between patients with ulcerative or unclassified IBD diagnosed at prepubertal, pubertal or adult age. CONCLUSION: Prepubertal onset of CD is a risk for lower final height, independent of the initial disease location and the necessity for surgical interventions.

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Factor D is an essential enzyme of the alternative pathway of complement. Its catabolism is mainly renal. The concentration of factor D increases with renal failure, and is approximately 10-fold higher in patients with end-stage renal disease. The accumulation of factor D is responsible for an enhancement of alternative pathway activation. Whether this excess of factor D has pathophysiological consequences remains to be determined, however, complement activation might participate in adverse effects during hemodialysis and in the progression of renal injury.

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Transcription initiation at eukaryotic protein-coding gene promoters is regulated by a complex interplay of site-specific DNA-binding proteins acting synergistically or antagonistically. Here, we have analyzed the mechanisms of synergistic transcriptional activation between members of the CCAAT-binding transcription factor/nuclear factor I (CTF/NF-I) family and the estrogen receptor. By using cotransfection experiments with HeLa cells, we show that the proline-rich transcriptional activation domain of CTF-1, when fused to the GAL4 DNA-binding domain, synergizes with each of the two estrogen receptor-activating regions. Cooperative DNA binding between the GAL4-CTF-1 fusion and the estrogen receptor does not occur in vitro, and in vivo competition experiments demonstrate that both activators can be specifically inhibited by the overexpression of a proline-rich competitor, indicating that a common limiting factor is mediating their transcriptional activation functions. Furthermore, the two activators functioning synergistically are much more resistant to competition than either factor alone, suggesting that synergism between CTF-1 and the estrogen receptor is the result of a stronger tethering of the limiting target factor(s) to the two promoter-bound activators.

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Neuropeptides and their receptors are present in human skin, and their importance for cutaneous homeostasis and during wound healing is increasingly appreciated. However, there is currently a lack of understanding of the molecular mechanisms by which their signaling modulates keratinocyte function. Here, we show that δ-opioid receptor (DOPr) activation inhibits proliferation of human keratinocytes, resulting in decreased epidermal thickness in an organotypic skin model. DOPr signaling markedly delayed induction of keratin intermediate filament (KRT10) during in vitro differentiation and abolished its induction in the organotypic skin model. This was accompanied by deregulation of involucrin (IVL), loricrin, and filaggrin. Analysis of the transcription factor POU2F3, which is involved in regulation of KRT10, IVL, and profilaggrin expression, revealed a DOPr-mediated extracellular signal-regulated kinase (ERK)-dependent downregulation of this factor. We propose that DOPr signaling specifically activates the ERK 1/2 mitogen-activated protein kinase pathway to regulate keratinocyte functions. Complementing our earlier studies in DOPr-deficient mice, these data suggest that DOPr activation in human keratinocytes profoundly influences epidermal morphogenesis and homeostasis.

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Macrophage migration inhibitory factor (MIF) is a homotrimeric multifunctional proinflammatory cytokine that has been implicated in the pathogenesis of several inflammatory and autoimmune diseases. Current therapeutic strategies for targeting MIF focus on developing inhibitors of its tautomerase activity or modulating its biological activities using anti-MIF neutralizing antibodies. Herein we report a new class of isothiocyanate (ITC)-based irreversible inhibitors of MIF. Modification by benzyl isothiocyanate (BITC) and related analogues occurred at the N-terminal catalytic proline residue without any effect on the oligomerization state of MIF. Different alkyl and arylalkyl ITCs modified MIF with nearly the same efficiency as BITC. To elucidate the mechanism of action, we performed detailed biochemical, biophysical, and structural studies to determine the effect of BITC and its analogues on the conformational state, quaternary structure, catalytic activity, receptor binding, and biological activity of MIF. Light scattering, analytical ultracentrifugation, and NMR studies on unmodified and ITC-modified MIF demonstrated that modification of Pro1 alters the tertiary, but not the secondary or quaternary, structure of the trimer without affecting its thermodynamic stability. BITC induced drastic effects on the tertiary structure of MIF, in particular residues that cluster around Pro1 and constitute the tautomerase active site. These changes in tertiary structure and the loss of catalytic activity translated into a reduction in MIF receptor binding activity, MIF-mediated glucocorticoid overriding, and MIF-induced Akt phosphorylation. Together, these findings highlight the role of tertiary structure in modulating the biochemical and biological activities of MIF and present new opportunities for modulating MIF biological activities in vivo.