987 resultados para Covalent cross-link


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A central question in developmental biology is how multicellular organisms coordinate cell division and differentiation to determine organ size. In Arabidopsis roots, this balance is controlled by cytokinin-induced expression of SHORT HYPOCOTYL 2 (SHY2) in the so-called transition zone of the meristem, where SHY2 negatively regulates auxin response factors (ARFs) by protein-protein interaction. The resulting down-regulation of PIN-FORMED (PIN) auxin efflux carriers is considered the key event in promoting differentiation of meristematic cells. Here we show that this regulation involves additional, intermediary factors and is spatio-temporally constrained. We found that the described cytokinin-auxin crosstalk antagonizes BREVIS RADIX (BRX) activity in the developing protophloem. BRX is an auxin-responsive target of the prototypical ARF MONOPTEROS (MP), a key promoter of vascular development, and transiently enhances PIN3 expression to promote meristem growth in young roots. At later stages, cytokinin induction of SHY2 in the vascular transition zone restricts BRX expression to down-regulate PIN3 and thus limit meristem growth. Interestingly, proper SHY2 expression requires BRX, which could reflect feedback on the auxin responsiveness of SHY2 because BRX protein can directly interact with MP, likely acting as a cofactor. Thus, cross-regulatory antagonism between BRX and SHY2 could determine ARF activity in the protophloem. Our data suggest a model in which the regulatory interactions favor BRX expression in the early proximal meristem and SHY2 prevails because of supplementary cytokinin induction in the later distal meristem. The complex equilibrium of this regulatory module might represent a universal switch in the transition toward differentiation in various developmental contexts.

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Although approximately 50% of Down Syndrome (DS) patients have heart abnormalities, they exhibit an overprotection against cardiac abnormalities related with the connective tissue, for example a lower risk of coronary artery disease. A recent study reported a case of a person affected by DS who carried mutations in FBN1, the gene causative for a connective tissue disorder called Marfan Syndrome (MFS). The fact that the person did not have any cardiac alterations suggested compensation effects due to DS. This observation is supported by a previous DS meta-analysis at the molecular level where we have found an overall upregulation of FBN1 (which is usually downregulated in MFS). Additionally, that result was cross-validated with independent expression data from DS heart tissue. The aim of this work is to elucidate the role of FBN1 in DS and to establish a molecular link to MFS and MFS-related syndromes using a computational approach. To reach that, we conducted different analytical approaches over two DS studies (our previous meta-analysis and independent expression data from DS heart tissue) and revealed expression alterations in the FBN1 interaction network, in FBN1 co-expressed genes and FBN1-related pathways. After merging the significant results from different datasets with a Bayesian approach, we prioritized 85 genes that were able to distinguish control from DS cases. We further found evidence for several of these genes (47%), such as FBN1, DCN, and COL1A2, being dysregulated in MFS and MFS-related diseases. Consequently, we further encourage the scientific community to take into account FBN1 and its related network for the study of DS cardiovascular characteristics.

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Contains information about the staff and athletes of the Iowa Hawkeyes Track and Field team for the 1984/85 academic school year. Also includes past year's results, team records, quick facts and schedule.

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Head space gas chromatography with flame-ionization detection (HS-GC-FID), ancl purge and trap gas chromatography-mass spectrometry (P&T-GC-MS) have been used to determine methyl-tert-butyl ether (MTBE) and benzene, toluene, and the ylenes (BTEX) in groundwater. In the work discussed in this paper measures of quality, e.g. recovery (94-111%), precision (4.6 - 12.2%), limits of detection (0.3 - 5.7 I~g L 1 for HS and 0.001 I~g L 1 for PT), and robust-ness, for both methods were compared. In addition, for purposes of comparison, groundwater samples from areas suffering from odor problems because of fuel spillage and tank leakage were analyzed by use of both techniques. For high concentration levels there was good correlation between results from both methods.

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Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting onequarter of the world"s adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk. Methods and results: We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of 1.9 mm Hg [95% confidence interval (CI): 3.4; 0.6] and 2.6 mm Hg (CI: 4.2; 1.0), respectively, and reduced diastolic BP of 1.5 mm Hg (CI: 2.3; 0.6) and 1.9 mm Hg (CI: 2.8; 1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR Z 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR Z 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group. Conclusions: Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.

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Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting onequarter of the world"s adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk. Methods and results: We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of 1.9 mm Hg [95% confidence interval (CI): 3.4; 0.6] and 2.6 mm Hg (CI: 4.2; 1.0), respectively, and reduced diastolic BP of 1.5 mm Hg (CI: 2.3; 0.6) and 1.9 mm Hg (CI: 2.8; 1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR Z 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR Z 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group. Conclusions: Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.

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Objectives: Many drugs, both illicit or for medication, are known to influence driving abilities and increase risks of accidents. We explored the prevalence of psychoactive substances in a random sample of drivers in Switzerland. Methods: Saliva samples from 1078 random drivers were collected at 24 different locations in Western Switzerland from October 2006 to April 2008 for complete toxicological analysis using liquid chromatography/tandem mass spectrometry. Results: Provisional results are available for 437 drivers. 6.2% (CI95% 4.1 to 8.9) were under the influence of illicit drugs and 8.7% under psychoactive medication (CI95% 6.2 to 11.7). 37 drivers (8.5%) were under the influence of alcohol of which 14 (3.2%) were above 0.8 mg/L. 21 drivers (4.8%) were under the combined influence of more than one psychoactive substance; however only 4 drivers (0.9%) were under both the influence of medication and alcohol. Looking more specifically at illicit substances, 22 (5.0%) were positive to cocaine, 5 (1.1%) to cannabis, and 2 (0.5%) to amphetamines ; for psychoactive medication, 17 (3.9%) were positive to benzodiazepines, 16 (3.7%) to antidepressors, 7 (1.6%) to opiates, 7 (1.6%) to neuroleptics, and 3 (0.7%) to other substances influencing driving abilities. 17/21 drivers did not self-report their consumption of drugs whereas only 9/35 failed mentioning their medication. Men drivers were 3.2 times (CI95% 1.1 to 9.5) more likely to be under the influence of illicit drugs than women. Full results will be reported when laboratory data will be available in April. Conclusions: Driving under the influence of psychoactive substances is common. In Western Switzerland, prevention messages could focus on men, driving under medication or cocaine.

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Bone morphogenetic proteins (Bmps) regulate the expression of the proneural gene Atoh1 and the generation of hair cells in the developing inner ear. The present work explored the role of Inhibitor of Differentiation genes (Id1-3) in this process. The results show that Id genes are expressed in the prosensory domains of the otic vesicle, along with Bmp4 and Bmp7. Those domains exhibit high levels of the phosphorylated form of Bmp-responding R-Smads (P-Smad1,5,8), and of Bmp-dependent Smad transcriptional activity as shown by the BRE-tk-EGFP reporter. Increased Bmp signaling induces the expression of Id1-3 along with the inhibition of Atoh1. Conversely, the Bmp antagonist Noggin or the Bmp-receptor inhibitor Dorsomorphin elicit opposite effects, indicating that Bmp signaling is necessary for Id expression and Atoh1 regulation in the otocyst. The forced expression of Id3 is sufficient to reduce Atoh1 expression and to prevent the expression of hair cell differentiation markers. Together, these results suggest that Ids are part of the machinery that mediates the regulation of hair cell differentiation exerted by Bmps. In agreement with that, during hair cell differentiation Bmp4 expression, P-Smad1,5,8 levels and Id expression are downregulated from hair cells. However, Ids are also downregulated from the supporting cells which contrarily to hair cells exhibit high levels of Bmp4 expression, P-Smad1,5,8, and BRE-tk-EGFP activity, suggesting that in these cells Ids escape from Bmp/Smad signaling. The differential regulation of Ids in time and space may underlie the multiple functions of Bmp signaling during sensory organ development.

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Subjective response to neuroleptics is essential to long term observance of treatment and quality of life of patients. Numerous factors (pharmacological, relational and psychopathological) are responsible of this subjective response. Objectives of this study are: (a) to examine psychometric features of the french version of the Drug Attitude Inventory (DAI-30) [13] and (b) to explore pharmacological, relational and psychopathological factors related to this subjective response. Subjects and methods: 78 subjects were rated (self rated response rate 61% (n = 48)) for (a) subjective response to neuroleptics, (b) compliance, (c) therapeutic alliance, (d) symptoms (e) severity of disorder. RESULTS: Factor analysis yielded 2 main clinically relevant factors, similar to the original version: (I) global subjective response and (II) specific subjective response. Internal consistency is high. Correspondance analysis showed two important dimensions in the treatment of schizophrenic patients: (I) Recovery--aggravation, (II) Therapeutic ambition--positive or negative symptoms. CONCLUSION: French version of DAI-30 seems to have a similar structure and psychometric features as the original version. It shows concordance with the degree of compliance. Pharmacological factors are not the only factors implicated in subjective response, but are still to be identified. Limitations of our study are: (a) nonhomogenous indication for treatment, (b) small rate and degree of non compliance in our sample. Relationships between therapeutic ambition, type of symptoms and treatment outcome should be further studied.

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OBJECTIVES: Leptin may be involved in the regulation of body weight, food intake, and energy expenditure. In view of a possible link between leptin concentrations and diabetes that has been suggested in obese rodents, we investigated the potential relationship between serum leptin concentrations and hyperglycaemia in French patients with morbid obesity. SUBJECTS: Fasting leptin concentrations were measured in 241 morbidly obese patients with various degrees of glucose tolerance in a cross-sectional study. RESULTS: Fasting serum leptin concentrations did not differ between normoglycaemia (NG, 61.5 +/- 24.0 ng/ml) and glucose intolerant morbidly obese subjects (IGT, 56.5 +/- 18.5 ng/ml) and were slightly lower in those with controlled diabetes (55.1 +/- 30.3 ng/ml, P = 0.06 when compared to NG subjects). In contrast, leptin concentrations were 30% lower in patients with poorly controlled diabetes (43.0 +/- 22.2 ng/ml, P = 0.001 vs NG subjects). Leptin concentrations were negatively correlated with fasting glucose in all groups combined (p = -0.24, P = 0.0001) and particularly in NIDDM subjects (p = 0.31, P = 0.0054). Although leptin concentrations were higher in women than in men, similar significant correlation with fasting glucose was found when females were analyzed separately. A positive correlation was found with BMI (p = 0.25, P = 0.0001) in all groups. Multivariate analysis revealed that fasting glucose was independently associated with serum leptin concentrations (F = 12.5, P = 0.0005). Sex, age, BMI, waist/hip ratio, fasting glucose and insulin, total cholesterol and triglycerides, tested in the model, explained 42% of the leptin variability in this population. CONCLUSIONS: Poorly controlled diabetes was accompanied by a significant reduction of serum leptin concentrations in morbidly obese subjects. We suggest that a relative leptin deficiency (lower than expected for the BMI) associated with insulin deficiency in this population might contribute to a vicious cycle maintaining (or even worsening) obesity itself and/or its metabolic complications.

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Aim. Several software packages (SWP) and models have been released for quantification of myocardial perfusion (MP). Although they all are validated against something, the question remains how well their values agree. The present analysis focused on cross-comparison of three SWP for MP quantification of 13N-ammonia PET studies. Materials & Methods. 48 rest and stress MP 13N-ammonia PET studies of hypertrophic cardiomyopathy (HCM) patients (Sciagrà et al., 2009) were analysed with three SW packages - Carimas, PMOD, and FlowQuant - by three observers blinded to the results of each other. All SWP implement the one-tissue-compartment model (1TCM, DeGrado et al. 1996), and first two - the two-tissue-compartment model (2TCM, Hutchins et al. 1990) as well. Linear mixed model for the repeated measures was fitted to the data. Where appropriate we used Bland-Altman plots as well. The reproducibility was assessed on global, regional and segmental levels. Intraclass correlation coefficients (ICC), differences between the SWPs and between models were obtained. ICC≥0.75 indicated excellent reproducibility, 0.4≤ICC<0.75 indicated fair to good reproducibility, ICC<0.4 - poor reproducibility (Rosner, 2010). Results. When 1TCM MP values were compared, the SW agreement on global and regional levels was excellent, except for Carimas vs. PMOD at RCA: ICC=0.715 and for PMOD vs. FlowQuant at LCX:ICC=0.745 which were good. In segmental analysis in five segments: 7,12,13, 16, and 17 the agreement between all SWP was excellent; in the remaining 12 segments the agreement varied between the compared SWP. Carimas showed excellent agreement with FlowQuant in 13 segments and good in four - 1, 5, 6, 11: 0.687≤ICCs≤0.73; Carimas had excellent agreement with PMOD in 11 segments, good in five_4, 9, 10, 14, 15: 0.682≤ICCs≤0.737, and poor in segment 3: ICC=0.341. PMOD had excellent agreement with FlowQuant in eight segments and substantial-to-good in nine_1, 2, 3, 5, 6,8-11: 0.585≤ICCs≤0.738. Agreement between Carimas and PMOD for 2TCM was good at a global level: ICC=0.745, excellent at LCX (0.780) and RCA (0.774), good at LAD (0.662); agreement was excellent for ten segments, fair-to-substantial for segments 2, 3, 8, 14, 15 (0.431≤ICCs≤0.681), poor for segments 4 (0.384) and 17 (0.278). Conclusions. The three SWP used by different operators to analyse 13N-ammonia PET MP studies provide results that agree well at a global level, regional levels, and mostly well even at a segmental level. Agreement is better for 1TCM. Poor agreement at segments 4 and 17 for 2TCM needs further clarification.

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This paper evaluates the global welfare impact of observed levels of migration using a quantitativemulti-sector model of the world economy calibrated to aggregate and firm-level data.Our framework features cross-country labor productivity differences, international trade, remittances,and a heterogeneous workforce. We compare welfare under the observed levels ofmigration to a no-migration counterfactual. In the long run, natives in countries that receiveda lot of migration -such as Canada or Australia- are better o due to greater product varietyavailable in consumption and as intermediate inputs. In the short run the impact of migrationon average welfare in these countries is close to zero, while the skilled and unskilled nativestend to experience welfare changes of opposite signs. The remaining natives in countries withlarge emigration flows -such as Jamaica or El Salvador- are also better off due to migration,but for a different reason: remittances. The welfare impact of observed levels of migration issubstantial, at about 5 to 10% for the main receiving countries and about 10% in countries withlarge incoming remittances. Our results are robust to accounting for imperfect transferabilityof skills, selection into migration, and imperfect substitution between natives and immigrants.

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Objectives:To analyse which are the main variables that influence primary care professionals, in the prescription of antibiotics in patients with acute pharyngitis.To analyse which is the diagnosis pattern used by primary care professionals towards cutepharyngitis. To recognize the clinical and analytical criteria that primary care professionals use, to determine antibiotic treatment in acute pharyngitis.To identify the main clinical variables related with the prescription of antibiotics by primary care professionals, in acute pharyngitis treatment. Design: Cross-­‐sectional study Participants:165 primary care professionals from the Sanitary Region of Girona not attending paediatric patients and randomly selected from 29 ABS managed by two of the main health care providers: Insitut Català de la Salut (ICS) and Institut d’Assistència Sanitària (IAS) Main outcome measures: Each participant will fill out a questionnaire with personal and workplace questions, as well as about knowledge and attitude in front of the acute pharyngitis caused by group A streptococci. They will also answer 4 clinical questions about correct treatment and diagnosis of acute pharyngitis caused by group A streptococci

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The ground-penetrating radar (GPR) geophysical method has the potential to provide valuable information on the hydraulic properties of the vadose zone because of its strong sensitivity to soil water content. In particular, recent evidence has suggested that the stochastic inversion of crosshole GPR traveltime data can allow for a significant reduction in uncertainty regarding subsurface van Genuchten-Mualem (VGM) parameters. Much of the previous work on the stochastic estimation of VGM parameters from crosshole GPR data has considered the case of steady-state infiltration conditions, which represent only a small fraction of practically relevant scenarios. We explored in detail the dynamic infiltration case, specifically examining to what extent time-lapse crosshole GPR traveltimes, measured during a forced infiltration experiment at the Arreneas field site in Denmark, could help to quantify VGM parameters and their uncertainties in a layered medium, as well as the corresponding soil hydraulic properties. We used a Bayesian Markov-chain-Monte-Carlo inversion approach. We first explored the advantages and limitations of this approach with regard to a realistic synthetic example before applying it to field measurements. In our analysis, we also considered different degrees of prior information. Our findings indicate that the stochastic inversion of the time-lapse GPR data does indeed allow for a substantial refinement in the inferred posterior VGM parameter distributions compared with the corresponding priors, which in turn significantly improves knowledge of soil hydraulic properties. Overall, the results obtained clearly demonstrate the value of the information contained in time-lapse GPR data for characterizing vadose zone dynamics.

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Antigen receptor-induced NF-kappaB activation depends on receptor-proximal and -distal signaling events. Two papers in this issue of Immunity demonstrate that PKC-dependent phosphorylation of CARMA1 is the critical molecular link that controls the activation of the IKK signalosome and NF-kappaB.