44 resultados para 1047
Resumo:
The aim of the study was to analyse the degree to which gestational age (GA) has been shortened due to prenatal diagnosis of gastrointestinal malformations (GIM). The data source for the study was 14 population-based registries of congenital malformations (EUROCAT). All liveborn infants with GIMs and without chromosomal anomalies, born 1997-2002, were included. The 14 registries identified 1047 liveborn infants with one or more GIMs (oesophageal atresia, duodenal atresia, omphalocele, gastroschisis and diaphragmatic hernia). Median GA at birth was lower in prenatally diagnosed cases for all five malformations, although not statistically significant for gastroschisis. There was little difference in median birthweight by GA for the pre- and postnatally diagnosed infants. The difference in GA at birth between prenatally and postnatally diagnosed infants with GIMs is enough to increase the risk of mortality for the prenatally diagnosed infants. Clinicians need to balance the risk of early delivery against the benefits of clinical convenience when making case management decisions after prenatal diagnosis. Very few studies have been able to show benefits of prenatal diagnosis of congenital malformations for liveborn infants. This may be because the benefits of prenatal diagnosis are outweighed by the problems arising from a lower GA at birth.
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Elevated serum ferritin levels may reflect a systemic inflammatory state as well as increased iron storage, both of which may contribute to an unfavorable outcome of chronic hepatitis C (CHC). We therefore performed a comprehensive analysis of the role of serum ferritin and its genetic determinants in the pathogenesis and treatment of CHC. To this end, serum ferritin levels at baseline of therapy with pegylated interferon-alpha and ribavirin or before biopsy were correlated with clinical and histological features of chronic hepatitis C virus (HCV) infection, including necroinflammatory activity (N = 970), fibrosis (N = 980), steatosis (N = 886), and response to treatment (N = 876). The association between high serum ferritin levels (> median) and the endpoints was assessed by logistic regression. Moreover, a candidate gene as well as a genome-wide association study of serum ferritin were performed. We found that serum ferritin ≥ the sex-specific median was one of the strongest pretreatment predictors of treatment failure (univariate P < 0.0001, odds ratio [OR] = 0.45, 95% confidence interval [CI] = 0.34-0.60). This association remained highly significant in a multivariate analysis (P = 0.0002, OR = 0.35, 95% CI = 0.20-0.61), with an OR comparable to that of interleukin (IL)28B genotype. When patients with the unfavorable IL28B genotypes were stratified according to high versus low ferritin levels, SVR rates differed by > 30% in both HCV genotype 1- and genotype 3-infected patients (P < 0.001). Serum ferritin levels were also independently associated with severe liver fibrosis (P < 0.0001, OR = 2.67, 95% CI = 1.68-4.25) and steatosis (P = 0.002, OR = 2.29, 95% CI = 1.35-3.91), but not with necroinflammatory activity (P = 0.3). Genetic variations had only a limited impact on serum ferritin levels. Conclusion: In patients with CHC, elevated serum ferritin levels are independently associated with advanced liver fibrosis, hepatic steatosis, and poor response to interferon-alpha-based therapy.
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PURPOSE: Quantification of myocardial blood flow (MBF) with generator-produced (82)Rb is an attractive alternative for centres without an on-site cyclotron. Our aim was to validate (82)Rb-measured MBF in relation to that measured using (15)O-water, as a tracer 100% of which can be extracted from the circulation even at high flow rates, in healthy control subject and patients with mild coronary artery disease (CAD). METHODS: MBF was measured at rest and during adenosine-induced hyperaemia with (82)Rb and (15)O-water PET in 33 participants (22 control subjects, aged 30 ± 13 years; 11 CAD patients without transmural infarction, aged 60 ± 13 years). A one-tissue compartment (82)Rb model with ventricular spillover correction was used. The (82)Rb flow-dependent extraction rate was derived from (15)O-water measurements in a subset of 11 control subjects. Myocardial flow reserve (MFR) was defined as the hyperaemic/rest MBF. Pearson's correlation r, Bland-Altman 95% limits of agreement (LoA), and Lin's concordance correlation ρ (c) (measuring both precision and accuracy) were used. RESULTS: Over the entire MBF range (0.66-4.7 ml/min/g), concordance was excellent for MBF (r = 0.90, [(82)Rb-(15)O-water] mean difference ± SD = 0.04 ± 0.66 ml/min/g, LoA = -1.26 to 1.33 ml/min/g, ρ(c) = 0.88) and MFR (range 1.79-5.81, r = 0.83, mean difference = 0.14 ± 0.58, LoA = -0.99 to 1.28, ρ(c) = 0.82). Hyperaemic MBF was reduced in CAD patients compared with the subset of 11 control subjects (2.53 ± 0.74 vs. 3.62 ± 0.68 ml/min/g, p = 0.002, for (15)O-water; 2.53 ± 1.01 vs. 3.82 ± 1.21 ml/min/g, p = 0.013, for (82)Rb) and this was paralleled by a lower MFR (2.65 ± 0.62 vs. 3.79 ± 0.98, p = 0.004, for (15)O-water; 2.85 ± 0.91 vs. 3.88 ± 0.91, p = 0.012, for (82)Rb). Myocardial perfusion was homogeneous in 1,114 of 1,122 segments (99.3%) and there were no differences in MBF among the coronary artery territories (p > 0.31). CONCLUSION: Quantification of MBF with (82)Rb with a newly derived correction for the nonlinear extraction function was validated against MBF measured using (15)O-water in control subjects and patients with mild CAD, where it was found to be accurate at high flow rates. (82)Rb-derived MBF estimates seem robust for clinical research, advancing a step further towards its implementation in clinical routine.
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Trait decoupling, wherein evolutionary release of constraints permits specialization of formerly integrated structures, represents a major conceptual framework for interpreting patterns of organismal diversity. However, few empirical tests of this hypothesis exist. A central prediction, that the tempo of morphological evolution and ecological diversification should increase following decoupling events, remains inadequately tested. In damselfishes (Pomacentridae), a ceratomandibular ligament links the hyoid bar and lower jaws, coupling two main morphofunctional units directly involved in both feeding and sound production. Here, we test the decoupling hypothesis by examining the evolutionary consequences of the loss of the ceratomandibular ligament in multiple damselfish lineages. As predicted, we find that rates of morphological evolution of trophic structures increased following the loss of the ligament. However, this increase in evolutionary rate is not associated with an increase in trophic breadth, but rather with morphofunctional specialization for the capture of zooplanktonic prey. Lineages lacking the ceratomandibular ligament also shows different acoustic signals (i.e. higher variation of pulse periods) from others, resulting in an increase of the acoustic diversity across the family. Our results support the idea that trait decoupling can increase morphological and behavioural diversity through increased specialization rather than the generation of novel ecotypes.
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The effects of bilateral electrolytic lesions of the entorhinal cortex were studied in male adult woodmice. Experiments were designed to allow separate analysis of the basal activity level and exploratory behavior. Activity recording was conducted in three situations: (a) 24-hr wheel running in the home cage pre- and postoperatively; (b) 24-hr activity composition in a large enclosure over 4 days, 5 to 9 days postoperatively; and (c) sequence and duration of visits in a residential plus maze 11 to 14 days postoperatively. Medial entorhinal cortex lesion involving the para- and presubiculum increased the 24-hr amount of movements in the enclosure (b) without increasing wheel running in any situation (a or b). This lesion also enhanced the locomotor reactivity to being introduced into the plus maze and impaired exploratory behavior. This last effect was equally apparent when the whole situation was new or when part of the familiar maze was modified. Lesioned woodmice did notice the new element but did not show active focalization of their behavior on that element. Data showed that lesion induced hyperactivity and changes of exploratory behavior were not necessarily associated. Novelty detection was performed but it is not clear now on what information this discrimination was based.
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Background: Interventional catheterization is being increasingly used for relief of residual lesions in congenital heart disease. Exact anatomical imaging is crucial in the planning of an intervention. This can be provided non-invasively and without radiation by contrast-enhanced MR angiography (CEMRA). Aim: To evaluate the accuracy of the measurements of the vessels obtained by CEMRA in comparison to those obtained by conventional X-ray angiography (CXA). Methods: Retrospective blinded measurement of the diameters of aorta and pulmonary arteries on the CEMRA and CXA images, in the same locations. Comparison of the results by Pearson correlation and by calculating the limits of agreement. Results: Twenty-one children with congenital heart disease, mean age 5.6 +- 5.2 years, weight 21.1 +- 18.4 kg, underwent CEMRA and catheterization for assessment or treatment of a residual lesion. The time interval between the CEMRA and the CXA examination was 2.6 +- 2.3 months. A total of 98 measurements, 37 of the aorta and 61 of the pulmonary arteries were performed on the images obtained by each technique. The correlation between CEMRA and CXA measurements was excellent, r = 0.97, p < 0.0001. The mean difference between the two techniques was 0.018 +- 1.1mm; the limits of agreement were -2.14 and +2.18mm. Similar agreement was found for measures of the aorta (r +- 0.97, mean difference 0.20 = 1.08 mm) and of the pulmonary arteries (r +- 0.97, mean difference 0.048 = 0.89 mm). Conclusions: CEMRA provide accurate quantitative anatomical information, which highly agrees with CXA data, and can therefore be used for planning interventional catheterization.
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We have recently reported that the inhibition of endothelial cell COX-2 by non-steroidal anti-inflammatory drugs suppresses alpha(V)beta(3)- (but not alpha(5)beta(1)-) dependent Rac activation, endothelial cell spreading, migration, and angiogenesis (Dormond, O., Foletti, A., Paroz, C., and Ruegg, C. (2001) Nat. Med. 7, 1041-1047). Here we investigated the role of the COX-2 metabolites PGE(2) and TXA2 in regulating human umbilical vein endothelial cell (HUVEC) adhesion and spreading. We report that PGE(2) accelerated alpha(V)beta(3)-mediated HUVEC adhesion and promoted Rac activation and cell spreading, whereas the TXA2 agonist retarded adhesion and inhibited spreading. We show that the cAMP level and the cAMP-regulated protein kinase A (PKA) activity are critical mediators of these PGE(2) effects. alpha(V)beta(3)-mediated adhesion induced a transient COX-2-dependent rise in cAMP levels, whereas the cell-permeable cAMP analogue 8-brcAMP accelerated adhesion, promoted Rac activation, and cell spreading in the presence of the COX-2 inhibitor NS-398. Pharmacological inhibition of PKA completely blocked alpha(V)beta(3)-mediated adhesion. A constitutively active Rac mutant (L61Rac) rescued alpha(V)beta(3)-dependent spreading in the presence of NS398 or, but did not accelerate adhesion, whereas a dominant negative Rac mutant (N17Rac) suppressed spreading without affecting adhesion. alpha(5)beta(1)-mediated HUVEC adhesion, Rac activation, and spreading were not affected by PGE(2), 8-brcAMP, or the inhibition of PKA. In conclusion, these results demonstrate that PGE(2) accelerates alpha(V)beta(3)-mediated endothelial cell adhesion through cAMP-dependent PKA activation and induces alpha(V)beta(3)-dependent spreading via cAMP- and PKA-dependent Rac activation and may contribute to the further understanding of the regulation of vascular integrins alpha(V)beta(3) by COX-2/PGE(2) during tumor angiogenesis and inflammation.
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This study investigated the influence of two warm-up protocols on neural and contractile parameters of knee extensors. A series of neuromuscular tests including voluntary and electrically evoked contractions were performed before and after running- (R (WU); slow running, athletic drills, and sprints) and strength-based (S (WU); bilateral 90 degrees back squats, Olympic lifting movements and reactivity exercises) warm ups (duration ~40 min) in ten-trained subjects. The estimated overall mechanical work was comparable between protocols. Maximal voluntary contraction torque (+15.6%; P < 0.01 and +10.9%; P < 0.05) and muscle activation (+10.9 and +12.9%; P < 0.05) increased to the same extent after R (WU) and S (WU), respectively. Both protocols caused a significant shortening of time to contract (-12.8 and -11.8% after R (WU) and S (WU); P < 0.05), while the other twitch parameters did not change significantly. Running- and strength-based warm ups induce similar increase in knee extensors force-generating capacity by improving the muscle activation. Both protocols have similar effects on M-wave and isometric twitch characteristics.
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Repetition of environmental sounds, like their visual counterparts, can facilitate behavior and modulate neural responses, exemplifying plasticity in how auditory objects are represented or accessed. It remains controversial whether such repetition priming/suppression involves solely plasticity based on acoustic features and/or also access to semantic features. To evaluate contributions of physical and semantic features in eliciting repetition-induced plasticity, the present functional magnetic resonance imaging (fMRI) study repeated either identical or different exemplars of the initially presented object; reasoning that identical exemplars share both physical and semantic features, whereas different exemplars share only semantic features. Participants performed a living/man-made categorization task while being scanned at 3T. Repeated stimuli of both types significantly facilitated reaction times versus initial presentations, demonstrating perceptual and semantic repetition priming. There was also repetition suppression of fMRI activity within overlapping temporal, premotor, and prefrontal regions of the auditory "what" pathway. Importantly, the magnitude of suppression effects was equivalent for both physically identical and semantically related exemplars. That the degree of repetition suppression was irrespective of whether or not both perceptual and semantic information was repeated is suggestive of a degree of acoustically independent semantic analysis in how object representations are maintained and retrieved.
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Background and aims: More than 30% of cancer patients develop a psychiatric disorder during the evolution of their disease. While evidence exists, that psychotherapy can improve psychological distress, questions, such as the prevalence of patients accepting psychotherapy, treatment indications and effectiveness of psychotherapeutic interventions in the oncology setting remain unanswered. The aims were: (1) To assess the prevalence of newly diagnosed cancer patients motivated to engage in psychotherapeutic interventions; (2) to identify those who benefit; and (3) to evaluate their effectiveness. Methods: Every new patient of the Oncology Service at the University Hospital Lausanne was informed of the possibility of benefitting from psychotherapeutic support. Patients who accepted were randomly assigned to individual psychotherapy or to a 4-month waiting list. Psychotherapies were formalized as psychodynamicoriented short interventions (1-4 sessions) or brief psychodynamic psychotherapies (16 sessions). Patients who refused psychotherapy were asked to participate in an observational group. Socio-demographic and medical data, anxiety, depression, alexithymia and quality of life (SCL- 90, HADS, TAS, EORTC) of all participants were evaluated at base line and at 1, 4, 8 and 12 -months Follow- Up. Results: So far 1047 patients have been approached, 20% were included in the study (intervention n=68, observation n=122), 32% were excluded, 22% could not be contacted and 26% refused to participate. At baseline, patients who accepted psychotherapeutic support showed higher depression and anxiety scores (HADS, SCL-90) compared to controls. 56% benefited from 4 sessions of psychological support, 44% engaged in 16 sessions of brief psychodynamic therapy. Conclusions: The preliminary results of this ongoing trial suggest that a minority of newly cancer patients accept psychotherapeutic intervention. These patients are more depressed than controls. Their motivation for short interventions and for brief psychotherapies is comparable.
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Cyclooxygenase-2 (COX-2), a key enzyme in prostaglandin synthesis, is highly expressed during inflammation and cellular transformation and promotes tumor progression and angiogenesis. We have previously demonstrated that endothelial cell COX-2 is required for integrin alphaVbeta3-dependent activation of Rac-1 and Cdc-42 and for endothelial cell spreading, migration, and angiogenesis (Dormond, O., Foletti, A., Paroz, C., and Ruegg, C. (2001) Nat. Med. 7, 1041-1047; Dormond, O., Bezzi, M., Mariotti, A., and Ruegg, C. (2002) J. Biol. Chem. 277, 45838-45846). In this study, we addressed the question of whether integrin-mediated cell adhesion may regulate COX-2 expression in endothelial cells. We report that cell detachment from the substrate caused rapid degradation of COX-2 protein in human umbilical vein endothelial cells (HUVEC) independent of serum stimulation. This effect was prevented by broad inhibition of cellular proteinases and by neutralizing lysosomal activity but not by inhibiting the proteasome. HUVEC adhesion to laminin, collagen I, fibronectin, or vitronectin induced rapid COX-2 protein expression with peak levels reached within 2 h and increased COX-2-dependent prostaglandin E2 production. In contrast, nonspecific adhesion to poly-L-lysine was ineffective in inducing COX-2 expression. Furthermore, the addition of matrix proteins in solution promoted COX-2 protein expression in suspended or poly-L-lysine-attached HUVEC. Adhesion-induced COX-2 expression was strongly suppressed by pharmacological inhibition of c-Src, phosphatidylinositol 3-kinase, p38, extracellular-regulated kinase 1/2, and, to a lesser extent, protein kinase C and by the inhibition of mRNA or protein synthesis. In conclusion, this work demonstrates that integrin-mediated cell adhesion and soluble integrin ligands contribute to maintaining COX-2 steady-state levels in endothelial cells by the combined prevention of lysosomal-dependent degradation and the stimulation of mRNA synthesis involving multiple signaling pathways.
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Cyclooxygenase-2 (COX-2), a key enzyme in arachidonic acid metabolism, is overexpressed in many cancers. Inhibition of COX-2 by nonsteroidal anti-inflammatory drugs (NSAIDs) reduces the risk of cancer development in humans and suppresses tumor growth in animal models. The anti-cancer effect of NSAIDs seems to involve suppression of tumor angiogenesis, but the underlying mechanism is not completely understood. Integrin alpha V beta 3 is an adhesion receptor critically involved in mediating tumor angiogenesis. Here we show that inhibition of endothelial-cell COX-2 by NSAIDs suppresses alpha V beta 3-dependent activation of the small GTPases Cdc42 and Rac, resulting in inhibition of endothelial-cell spreading and migration in vitro and suppression of fibroblast growth factor-2-induced angiogenesis in vivo. These results establish a novel functional link between COX-2, integrin alpha V beta 3 and Cdc42-/Rac-dependent endothelial-cell migration. Moreover, they provide a rationale to the understanding of the anti-angiogenic activity of NSAIDs.