905 resultados para LIMITED ROLE


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Recent theoretical writings suggest that the ineffective regulation of negative emotional states may reduce the ability of women to detect and respond effectively to situational and interpersonal factors that increase risk for sexual assault. However, little empirical research has explored this hypothesis. In the present study, it was hypothesized that prior sexual victimization and negative mood state would each independently predict poor risk recognition and less effective defensive actions in response to an analogue sexual assault vignette. Further, these variables were expected to interact to produce particularly impaired risk responses. Finally, that the in vivo emotion regulation strategy of suppression and corresponding cognitive resource usage (operationalized as memory impairment for the vignette) were hypothesized to mediate these associations. Participants were 668 female undergraduate students who were randomly assigned to receive a negative or neutral film mood induction followed by an audiotaped dating interaction during which they were instructed to indicate when the man had “gone too far” and describe an adaptive response to the situation. Approximately 33.5% of the sample reported a single victimization and 10% reported revictimization. Hypotheses were largely unsupported as sexual victimization history, mood condition, and their interaction did not impact risk recognition or adaptive responding. However, in vivo emotional suppression and cognitive resource usage were shown to predict delayed risk recognition only. Findings suggest that contrary to hypotheses, negative mood (as induced here) may not relate to risk recognition and response impairments. However, it may be important for victimization prevention programs that focus on risk perception to address possible underlying issues with emotional suppression and limited cognitive resources to improve risk perception abilities. Limitations and future directions are discussed.

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Purpose: In juvenile onset systemic lupus erythematosus (JoSLE), evidence for the association between vitamin D status, lupus activity, and bone health is very limited and not conclusive. The aim of this study was, therefore, to assess in JoSLE patients the possible relevance of vitamin D deficiency in disease and bone parameters. Methods: Fifty-seven JoSLE patients were initially compared to 37 age, race and body mass index (BMI) -matched healthy controls. The serum concentration of 25 hydroxyvitamin D (25OHD) was determined by radioimmunoassay. Patients with 25OHD deficiency (acurrency sign20 ng/mL) were compared to those with levels > 20 ng/mL. Disease activity was evaluated by SLE Disease Activity Index (SLEDAI). Bone mineral density (BMD) and body composition (BC) were measured using dual-energy X-ray absorptiometry (DXA). Results: 25OHD levels were similar in patients and controls (21.44 +/- 7.91 vs 22.54 +/- 8.25 ng/mL, p = 0.519), regardless of supplementation (65% of patients and none in controls). Thirty-one patients with 25OHD deficiency (acurrency sign20 ng/mL) were further compared to the 26 JoSLE patients with levels > 20 ng/mL. These two groups were well-balanced regarding vitamin D confounding variables: age (p = 0.100), ethnicity (p = 1.000), BMI (p = 0.911), season (p = 0.502), frequency of vitamin D supplementation (p = 0.587), creatinine (p = 0.751), renal involvement (p = 0.597), fat mass (p = 0.764), lean mass (p = 0.549), previous/current use of glucocorticoids(GC) (p = 1.0), immunosuppressors (p = 0.765), and mean current daily dose of GC (p = 0.345). Patients with vitamin D deficiency had higher SLEDAI (3.35 +/- 4.35 vs 1.00 +/- 2.48, p = 0.018), lower C4 levels (12.79 +/- 6.78 vs 18.38 +/- 12.24 mg/dL, p = 0.038), lower spine BMD (0.798 +/- 0.148 vs 0.880 +/- 0.127 g/cm2, p = 0.037) and whole body BMD (0.962 +/- 0.109 vs 1.027 +/- 0.098 g/cm2, p = 0.024). Conclusion: JoSLE vitamin D deficiency, in spite of conventional vitamin D supplementation, affects bone and disease activity status independent of therapy and fat mass reinforcing the recommendation to achieve adequate levels. Lupus (2012) 21, 1335-1342.

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In the process of creation of the Unified Health System (SUS) as a universal policy seeking to ensure comprehensive care, unscheduled assistance in primary healthcare units (UBS) is an unresolved challenge. The scope of this paper is to analyze the viewpoint of health professionals on the role of primary healthcare units in meeting this demand. It is a transversal study of qualitative data obtained through questionnaires and interviews with 106 medical practitioners from 6 emergency medical services and 190 professionals from 30 units. They explained why people seek emergency care for occurrences pertaining to primary care. The content analysis technique with thematic categories was used for data analysis. Lack of resources and problems with primary health unit work processes (50.8%) were the reasons most frequently cited by emergency care physicians to explain this inadequate demand. Only 33.3% of the health unit professionals agreed that these occurrences should be attended in the primary healthcare services. The limited viewpoint of the role of health services on the unscheduled care, particularly among primary care professionals, possibly leads to restrictive practices for access by the population.

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Aim The study aimed to determine the value of postchemoradiation biopsies, performed after significant tumour downsizing following neoadjuvant therapy, in predicting complete tumour regression in patients with distal rectal cancer. Method A retrospective comparative study was performed in patients with rectal cancer who achieved an incomplete clinical response after neoadjuvant chemoradiotherapy. Patients with significant tumour downsizing (> 30% of the initial tumour size) were compared with controls (< 30% reduction of the initial tumour size). During flexible proctoscopy carried out postchemoradiation, biopsies were performed using 3-mm biopsy forceps. The biopsy results were compared with the histopathological findings of the resected specimen. UICC (Union for International Cancer Control) ypTNM classification, tumour differentiation and regression grade were evaluated. The main outcome measures were sensitivity and specificity, negative and positive predictive values, and accuracy of a simple forceps biopsy for predicting pathological response after neoadjuvant chemoradiotherapy. Results Of the 172 patients, 112 were considered to have had an incomplete clinical response and were included in the study. Thirty-nine patients achieved significant tumour downsizing and underwent postchemoradiation biopsies. Overall, 53 biopsies were carried out. Of the 39 patients who achieved significant tumour downsizing, the biopsy result was positive in 25 and negative in 14. Only three of the patients with a negative biopsy result were found to have had a complete pathological response (giving a negative predictive value of 21%). Considering all biopsies performed, only three of 28 negative biopsies were true negatives, giving a negative predictive value of 11%. Conclusion In patients with distal rectal cancer undergoing neoadjuvant chemoradiation, post-treatment biopsies are of limited clinical value in ruling out persisting cancer. A negative biopsy result after a near-complete clinical response should not be considered sufficient for avoiding a radical resection.

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The reinforcement omission effect (ROE) has been attributed to both motivational and attentional consequences of surprising reinforcement omission. Recent evidence suggests that the basolateral complex of the amygdala is involved in motivational components related to reinforcement value, whereas the central nucleus of the amygdala is involved in the processing of the attentional consequences of surprise. This study was designed to verify whether the mechanisms involved in the ROE depend on the integrity of either the basolateral amygdala complex or central nucleus of the amygdala. The ROE was evaluated in rats with lesions of either the central nucleus or basolateral complex of the amygdala and trained on a fixed-interval schedule procedure (Experiment 1) and fixed-interval with limited hold signaled schedule procedure (Experiment 2). The results of Experiment 1 showed that sham-operated rats and rats with lesions of either the central nucleus or basolateral area displayed the ROE. In contrast, in Experiment 2, subjects with lesions of the central nucleus or basolateral complex of the amygdala exhibited a smaller ROE compared with sham-operated subjects. Thus, the effects of selective lesions of amygdala subregions on the ROE in rats depended on the training procedure. Furthermore, the absence of differences between the lesioned groups in either experiment did not allow the dissociation of attentional or motivational components of the ROE with functions of specific areas of the amygdala. Thus, results did not show a functional double-dissociation between the central nucleus and basolateral area in the ROE.

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Photosynthetic organisms have sought out the delicate balance between efficient light harvesting under limited irradiance and regulated energy dissipation under excess irradiance. One of the protective mechanisms is the thermal energy dissipation through the xanthophyll cycle that may transform harmlessly the excitation energy into heat and thereby prevent the formation of damaging active oxygen species (AOS). Violaxanthin deepoxidase (VDE) converts violaxanthin (V) to antheraxanthin (A) and zeaxanthin (Z) defending the photosynthetic apparatus from excess of light. Another important biological pathway is the chloroplast water-water cycle, which is referred to the electrons from water generated in PSII reducing atmospheric O2 to water in PSI. This mechanism is active in the scavenging of AOS, when electron transport is slowed down by the over-reduction of NADPH pool. The control of the VDE gene and the variations of a set of physiological parameters, such as chlorophyll florescence and AOS content, have been investigated in response to excess of light and drought condition using Arabidopsis thaliana and Arbutus unedo.. Pigment analysis showed an unambiguous relationship between xanthophyll de-epoxidation state ((A+Z)/(V+A+Z)) and VDE mRNA amount in not-irrigated plants. Unexpectedly, gene expression is higher during the night when xanthophylls are mostly epoxidated and VDE activity is supposed to be very low than during the day. The importance of the water-water cycle in protecting the chloroplasts from light stress has been examined through Arabidopsis plant with a suppressed expression of the key enzyme of the cycle: the thylakoid-attached copper/zinc superoxide dismutase. The analysis revealed changes in transcript expression during leaf development consistent with a signalling role of AOS in plant defence responses but no difference was found any in photosynthesis efficiency or in AOS concentration after short-term exposure to excess of light. Environmental stresses such as drought may render previously optimal light levels excessive. In these circumstances the intrinsic regulations of photosynthetic electron transport like xanthophyll and water-water cycles might modify metabolism and gene expression in order to deal with increasing AOS.

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[ES]Despite the rapid growth of new technologies in universities, there is still little empirical evidence on the incidence of certain e-learnings mechanisms on students’ success or failure, particularly among accounting students. According to the cognitive theory of multimedia learning, screencasts are an effective and efficient tool for enhancing students learning, particularly in online accounting education where face-to-face interactions between instructor and students are limited.

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In calcareous soils, which are a large share of agricultural soils worldwide, iron availability is limited. Consequently, the whole plant physiology is affected, because of the key role of iron in redox metabolism, resulting in reduced crop yield and quality. Peach cultivation is economically important in northern Italy, and is easily subjected to iron chlorosis. The management of iron nutrition in peach includes grafting on bicarbonate-tolerant rootstocks; other forms of management may be expensive and environmentally impacting. Four genotypes, used as rootstocks for peach and characterized by different degrees of tolerance to chlorosis, were tested in vitro on optimal and bicarbonate-enriched medium. Their redox status and antioxidant responses were assayed; the production and possible roles of nitric oxide (NO) and related compounds were also studied. The most sensitive genotypes show a stronger reduction of the antioxidant enzymatic activities and an increased oxidative stress. A high production of NO was found to be associated to resistant genotypes, whereas sensitive genotypes reacted to stress by downregulating nitrosoglutathione reductase activity. Therefore, NO is proposed to improve the internal iron availability, or to stimulate iron intake.

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Nowadays the environmental issues and the climatic change play fundamental roles in the design of urban spaces. Our cities are growing in size, many times only following immediate needs without a long-term vision. Consequently, the sustainable development has become not only an ethical but also a strategic need: we can no longer afford an uncontrolled urban expansion. One serious effect of the territory industrialisation process is the increase of urban air and surfaces temperatures compared to the outlying rural surroundings. This difference in temperature is what constitutes an urban heat island (UHI). The purpose of this study is to provide a clarification on the role of urban surfacing materials in the thermal dynamics of an urban space, resulting in useful indications and advices in mitigating UHI. With this aim, 4 coloured concrete bricks were tested, measuring their emissivity and building up their heat release curves using infrared thermography. Two emissivity evaluation procedures were carried out and subsequently put in comparison. Samples performances were assessed, and the influence of the colour on the thermal behaviour was investigated. In addition, some external pavements were analysed. Albedo and emissivity parameters were evaluated in order to understand their thermal behaviour in different conditions. Surfaces temperatures were recorded in a one-day measurements campaign. ENVI-met software was used to simulate how the tested materials would behave in two typical urban scenarios: a urban canyon and a urban heat basin. Improvements they can carry to the urban microclimate were investigated. Emissivities obtained for the bricks ranged between 0.92 and 0.97, suggesting a limited influence of the colour on this parameter. Nonetheless, white concrete brick showed the best thermal performance, whilst the black one the worst; red and yellow ones performed pretty identical intermediate trends. De facto, colours affected the overall thermal behaviour. Emissivity parameter was measured in the outdoor work, getting (as expected) high values for the asphalts. Albedo measurements, conducted with a sunshine pyranometer, proved the improving effect given by the yellow paint in terms of solar reflection, and the bad influence of haze on the measurement accuracy. ENVI-met simulations gave a demonstration on the effectiveness in thermal improving of some tested materials. In particular, results showed good performances for white bricks and granite in the heat basin scenario, and painted concrete and macadam in the urban canyon scenario. These materials can be considered valuable solutions in UHI mitigation.

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Treatment options in patients with persistent or locally recurrent cervical cancer are limited. The aim of this study was to determine the chance of cure and associated morbidity following pelvic exenteration.

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Clinical manifestations of lactase (LCT) deficiency include intestinal and extra-intestinal symptoms. Lactose hydrogen breath test (H2-BT) is considered the gold standard to evaluate LCT deficiency (LD). Recently, the single-nucleotide polymorphism C/T(-13910) has been associated with LD. The objectives of the present study were to evaluate the agreement between genetic testing of LCT C/T(-13910) and lactose H2-BT, and the diagnostic value of extended symptom assessment. Of the 201 patients included in the study, 194 (139 females; mean age 38, range 17-79 years, and 55 males, mean age 38, range 18-68 years) patients with clinical suspicion of LD underwent a 3-4 h H2-BT and genetic testing for LCT C/T(-13910). Patients rated five intestinal and four extra-intestinal symptoms during the H2-BT and then at home for the following 48 h. Declaring H2-BT as the gold standard, the CC(-13910) genotype had a sensitivity of 97% and a specificity of 95% with a of 0.9 in diagnosing LCT deficiency. Patients with LD had more intense intestinal symptoms 4 h following the lactose challenge included in the H2-BT. We found no difference in the intensity of extra-intestinal symptoms between patients with and without LD. Symptom assessment yielded differences for intestinal symptoms abdominal pain, bloating, borborygmi and diarrhoea between 120 min and 4 h after oral lactose challenge. Extra-intestinal symptoms (dizziness, headache and myalgia) and extension of symptom assessment up to 48 h did not consistently show different results. In conclusion, genetic testing has an excellent agreement with the standard lactose H2-BT, and it may replace breath testing for the diagnosis of LD. Extended symptom scores and assessment of extra-intestinal symptoms have limited diagnostic value in the evaluation of LD.

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Whitefish, genus Coregonus, show exceptional levels of phenotypic diversity with sympatric morphs occurring in numerous postglacial lakes in the northern hemisphere. Here, we studied the effects of human-induced eutrophication on sympatric whitefish morphs in the Swiss lake, Lake Thun. In particular, we addressed the questions whether eutrophication (i) induced hybridization between two ecologically divergent summer-spawning morphs through a loss of environmental heterogeneity, and (ii) induced rapid adaptive morphological changes through changes in the food web structure. Genetic analysis based on 11 microsatellite loci of 282 spawners revealed that the pelagic and the benthic morph represent highly distinct gene pools occurring at different relative proportions on all seven known spawning sites. Gill raker counts, a highly heritable trait, showed nearly discrete distributions for the two morphs. Multilocus genotypes characteristic of the pelagic morph had more gill rakers than genotypes characteristic of benthic morph. Using Bayesian methods, we found indications of recent but limited introgressive hybridization. Comparisons with historical gill raker data yielded median evolutionary rates of 0.24 haldanes and median selection intensities of 0.27 for this trait in both morphs for 1948-2004 suggesting rapid evolution through directional selection at this trait. However, phenotypic plasticity as an alternative explanation for this phenotypic change cannot be discarded. We hypothesize that both the temporal shifts in mean gill raker counts and the recent hybridization reflect responses to changes in the trophic state of the lake induced by pollution in the 1960s, which created novel selection pressures with respect to feeding niches and spawning site preferences.

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Members of the BMP and Wnt protein families play a relevant role in physiologic and pathologic bone turnover. Extracellular antagonists are crucial for the modulation of their activity. Lack of expression of the BMP antagonist noggin by osteoinductive, carcinoma-derived cell lines is a determinant of the osteoblast response induced by their bone metastases. In contrast, osteolytic, carcinoma-derived cell lines express noggin constitutively. We hypothesized that cancer cell-derived noggin may contribute to the pathogenesis of osteolytic bone metastasis of solid cancers by repressing bone formation. Intra-osseous xenografts of PC-3 prostate cancer cells induced osteolytic lesions characterized not only by enhanced osteoclast-mediated bone resorption, but also by decreased osteoblast-mediated bone formation. Therefore, in this model, uncoupling of the bone remodeling process contributes to osteolysis. Bone formation was preserved in the osteolytic lesions induced by noggin-silenced PC-3 cells, suggesting that cancer cell-derived noggin interferes with physiologic bone coupling. Furthermore, intra-osseous tumor growth of noggin-silenced PC-3 cells was limited, most probably as a result of the persisting osteoblast activity. This investigation provides new evidence for a model of osteolytic bone metastasis where constitutive secretion of noggin by cancer cells mediates inhibition of bone formation, thereby preventing repair of osteolytic lesions generated by an excess of osteoclast-mediated bone resorption. Therefore, noggin suppression may be a novel strategy for the treatment of osteolytic bone metastases.

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The progression of liver fibrosis in chronic hepatitis C has long been considered to be independent from viral genotypes. However, recent studies suggest an association between Hepatitis C virus (HCV) genotype 3 and accelerated liver disease progression. We completed a systematic review and meta-analysis of studies evaluating the association between HCV genotypes and fibrosis progression. PubMed, Embase and ISI Web of Knowledge databases were searched for cohort, cross-sectional and case-control studies on treatment-naïve HCV-infected adults in which liver fibrosis progression rate (FPR) was assessed by the ratio of fibrosis stage in one single biopsy to the duration of infection (single-biopsy studies) or from the change in fibrosis stage between two biopsies (paired biopsies studies). A random effect model was used to derive FPR among different HCV genotypes. Eight single-biopsy studies (3182 patients, mean/median duration of infection ranging from 9 to 21 years) and eight paired biopsies studies (mean interval between biopsies 2-12 years) met the selection criteria. The odds ratio for the association of genotype 3 with accelerated fibrosis progression was 1.52 (95% CI 1.12-2.07, P = 0.007) in single-biopsy studies and 1.37 (95% CI 0.87-2.17, P = 0.17) in paired biopsy studies. In conclusion, viral genotype 3 was associated with faster fibrosis progression in single-biopsy studies. This observation may have important consequences on the clinical management of genotype 3-infected patients. The association was not significant in paired biopsies studies, although the latter may be limited by important indication bias, short observation time and small sample size.

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Steatosis is a prominent feature of hepatitis C, especially in patients infected with genotype 3. The analysis of genetic polymorphisms influencing steatosis in chronic hepatitis C has been limited by the studies' small sample size, and important single nucleotide polymorphisms (SNPs), such as those in the patatin-like phospholipase family 3 protein (PNPLA3), were never evaluated.