972 resultados para dental treatment
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BACKGROUND: An early response to antipsychotic treatment in patients with psychosis has been associated with a better course and outcome. However, factors that predict treatment response are not well understood. The onset of schizophrenia and related disorders has been associated with increased levels of stress and hyper-activation of the hypothalamic-pituitary-adrenal (HPA) axis. This study examined whether pituitary volume at the onset of psychosis may be a potential predictor of early treatment response in first-episode psychosis (FEP) patients. METHODS: We investigated the relationship between baseline pituitary volume and symptomatic treatment response over 12 weeks using mixed model analysis in a sample of 42 drug-naïve or early treated FEP patients who participated in a controlled dose-finding study of quetiapine fumarate. Logistic regression was used to examine predictors of treatment response. Pituitary volume was measured from magnetic resonance imaging scans that were obtained upon entry into the trial. RESULTS: Larger pituitary volume was associated with less improvement in overall psychotic symptoms (Brief Psychiatric Rating Scale (BPRS) P=0.031) and positive symptoms (BPRS positive symptom subscale P=0.010). Regardless of gender, patients with a pituitary volume at the 25th percentile (413 mm(3)) were approximately three times more likely to respond to treatment by week 12 than those at the 75th percentile (635 mm(3)) (odds ratio=3.07, CI: 0.90-10.48). CONCLUSION: The association of baseline pituitary volumes with early treatment response highlights the importance of the HPA axis in emerging psychosis. Potential implications for treatment strategies in early psychosis are discussed.
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Prolonged maternal deprivation leads to long-term alterations in hypothalamic–pituitary–adrenal (HPA) axis activity, disturbances of auditory information processing and neurochemical changes in the adult brain, some of which are similar to that observed in schizophrenia. Here we report the adult behavioural effects of maternal deprivation (12 h on postnatal days 9 and 11) in Wistar rats on paradigms of auditory information processing (prepulse inhibition), sensitivity to dopamimetics (amphetamine-induced hyper-locomotion) and cognition (T-maze delayed alternation and Morris water-maze). In addition, we examined the long-lasting effect of chronic 21-day corticosterone treatment during the post-pubertal period (i.e., postnatal days 56–76) on each of these behavioural paradigms in maternally deprived and control rats. Behavioural testing commenced 2 weeks after the termination of corticosterone treatment. Maternal deprivation led to a significant reduction in PPI and impaired spatial learning ability in adulthood, but did not affect the behavioural response to amphetamine. Post-pubertal chronic corticosterone treatment did not have any major long-lasting effects on any of the behavioural measures in either maternally deprived or control rats. Our findings further support maternal deprivation as an animal model of specific aspects of schizophrenia.
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A silk protein, fibroin, was isolated from the cocoons of the domesticated silkworm (Bombyx mori) and cast into membranes to serve as freestanding templates for tissue-engineered corneal cell constructs to be used in ocular surface reconstruction. In this study, we sought to enhance the attachment and proliferation of corneal epithelial cells by increasing the permeability of the fibroin membranes and the topographic roughness of their surface. By mixing the fibroin solution with poly(ethylene glycol) (PEG) of molecular weight 300 Da, membranes were produced with increased permeability and with topographic patterns generated on their surface. In order to enhance their mechanical stability, some PEG-treated membranes were also crosslinked with genipin. The resulting membranes were thoroughly characterized and compared to the non-treated membranes. The PEG-treated membranes were similar in tensile strength to the non-treated ones, but their elastic modulus was higher and elongation lower, indicating enhanced rigidity. The crosslinking with genipin did not induce a significant improvement in mechanical properties. In cultures of a human-derived corneal epithelial cell line (HCE-T), the PEG treatment of the substratum did not improve the attachment of cells and it enhanced only slightly the cell proliferation in the longer term. Likewise, primary cultures of human limbal epithelial cells grew equally well on both non-treated and PEG-treated membranes, and the stratification of cultures was consistently improved in the presence of an underlying culture of irradiated 3T3 feeder cells, irrespectively of PEG-treatment. Nevertheless, the cultures grown on the PEG-treated membranes in the presence of feeder cells did display a higher nuclear-to-cytoplasmic ratio suggesting a more proliferative phenotype. We concluded that while the treatment with PEG had a significant effect on some structural properties of the B. mori silk fibroin (BMSF) membranes, there were minimal gains in the performance of these materials as a substratum for corneal epithelial cell growth. The reduced mechanical stability of freestanding PEG-treated membranes makes them a less viable choice than the non-treated membranes.
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A two-dimensional variable-order fractional nonlinear reaction-diffusion model is considered. A second-order spatial accurate semi-implicit alternating direction method for a two-dimensional variable-order fractional nonlinear reaction-diffusion model is proposed. Stability and convergence of the semi-implicit alternating direct method are established. Finally, some numerical examples are given to support our theoretical analysis. These numerical techniques can be used to simulate a two-dimensional variable order fractional FitzHugh-Nagumo model in a rectangular domain. This type of model can be used to describe how electrical currents flow through the heart, controlling its contractions, and are used to ascertain the effects of certain drugs designed to treat arrhythmia.
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Issues Research shows that young people at risk of developing a substance use disorder often use substances to deal with problems, particularly relationship problems and emotional problems. Music listening is a widely available and engaging activity that may help young people address these problem areas. This study was part of a larger project to develop a phone app for young people in which they use music for emotional wellbeing. Approach Three focus groups with young people aged 15–25 years were conducted and the transcripts were analysed by three of the authors using a thematic analysis procedure (Braun & Clarke, 2006). Key Findings: Young people used music in four main ways to achieve wellbeing: relationship building through sharing music; cre- ating an ambience using music; using music to experience an emotion more fully; and using music to modify an emotion. Several mecha- nisms by which music achieved these functions were identified. Par- ticipants also articulated specific times when they would not use music and why. Discussion and Conclusions The information from these focus groups provides many avenues for the development of the app and for understanding how music listening helps young people to achieve wellbeing. These ideas can readily be used with young people at risk of developing substance use problems as it gives them an engaging and low cost alternative for managing their emotions and building relationships.
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Background: To effectively care for people who are terminally ill, including those without decision-making capacity, palliative care physicians must know and understand the legal standing of Advance Care Planning (ACP) in their jurisdiction of practice. This includes the use of advance directives/living wills (ADs) and substitute decision-makers (SDMs) who can legally consent to or refuse treatment if there is no valid AD. Aim: The study aimed to investigate the knowledge, attitudes and practices of medical specialists most often involved in end-of-life care in relation to the law on withholding/ withdrawing life-sustaining treatment (WWLST) from adults without decision-making capacity. Design/participants: A pre-piloted survey was posted to specialists in palliative, emergency, geriatric, renal and respiratory medicine, intensive care and medical oncology in three Australian States. Surveys were analysed using SPSS20 and SAS 9.3. Results: The overall response rate was 32% (867/2702); 52% from palliative care specialists. Palliative Care specialists and Geriatricians had significantly more positive attitudes towards the law (χ242 = 94.352; p < 0.001) and higher levels of knowledge about the WWLST law (χ27 = 30.033; p < 0.001), than did the other specialists, while still having critical gaps in their knowledge. Conclusions: A high level of knowledge of the law is essential to ensure that patients’ wishes and decisions, expressed through ACP, are respected to the maximum extent possible within the law, thereby according with the principles and philosophy of palliative care. It is also essential to protect health professionals from legal action resulting from unauthorised provision or removal of treatment.
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BACKGROUND Law is increasingly involved in clinical practice, particularly at the end of life, but undergraduate and postgraduate education in this area remains unsystematic. We hypothesised that attitudes to and knowledge of the law governing withholding/withdrawing treatment from adults without capacity (the WWLST law) would vary and demonstrate deficiencies among medical specialists. AIMS We investigated perspectives, knowledge and training of medical specialists in the three largest (populations and medical workforces) Australian states, concerning the WWLST law. METHODS Following expert legal review, specialist focus groups, pre-testing and piloting in each state, seven specialties involved with end-of-life care were surveyed, with a variety of statistical analyses applied to the responses. RESULTS Respondents supported the need to know and follow the law. There were mixed views about its helpfulness in medical decision-making. Over half the respondents conceded poor knowledge of the law; this was mirrored by critical gaps in knowledge that varied by specialty. There were relatively low but increasing rates of education from the undergraduate to continuing professional development (CPD) stages. Mean knowledge score did not vary significantly according to undergraduate or immediate postgraduate training, but CPD training, particularly if recent, resulted in greater knowledge. Case-based workshops were the preferred CPD instruction method. CONCLUSIONS Teaching of current and evolving law should be strengthened across all stages of medical education. This should improve understanding of the role of law, ameliorate ambivalence towards the law, and contribute to more informed deliberation about end-of-life issues with patients and families.
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Treatment that will not provide significant net benefit at the end of a person’s life (called futile treatment) is considered by many people to represent a major problem in the health sector, as it can waste resources and raise significant ethical issues. Medical treatment at the end of life involves a complex negotiation that implicates intergroup communication between health professionals, patients, and families, as well as between groups of health professionals. This study, framed by intergroup language theory, analyzed data from a larger project on futile treatment, in order to examine the intergroup language associated with futile treatment. Hospital doctors (N = 96) were interviewed about their understanding of treatment given to adult patients at the end of life that they considered futile. We conducted a discourse analysis on doctors’ descriptions of futile treatment provided by themselves and their in-group and out-group colleagues. Results pointed to an intergroup context, with patients, families, and colleagues as out-groups. In their descriptions, doctors justified their own decisions using the language of logic, ethics, and respect. Patients and families, however, were characterized in terms of wishing and wanting, as were outgroup colleagues. In addition, out-group doctors were described in strongly negative intergroup language.
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Several Eph receptor tyrosine kinases (RTKs) are commonly over-expressed in epithelial and mesenchymal cancers and are recognized as promising therapeutic targets. Although normal interaction between Eph receptors and their ephrin ligands stimulates kinase activity and is generally tumor suppressive, significant Eph over-expression allows activation of ligand- and/or kinase-independent signaling pathways that promote oncogenesis. Single-agent kinase inhibitors are widely used to target RTK-driven tumors but acquired and de novo resistance to such agents is a major limitation to effective clinical use. Accumulating evidence suggests that Ephs can be inhibited by “leaky” or low-specificity kinase inhibitors targeted at other RTKs. Such off-target effects may therefore inadvertently promote ligand- and/or kinase-independent oncogenic Eph signaling, thereby providing a new mechanism by which resistance to the RTK inhibitors can emerge. We propose that combining specific, non-leaky kinase inhibitors with tumor-suppressive stimulators of Eph signaling may provide more effective treatment options for overcoming treatment-induced resistance and clinical failure.
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Background Osteocytes, the most abundant cells in bone, havemultiple functions, including acting as mechanosensors and regulating mineralization. It is clear that osteocytes influence bone remodeling by controlling the differentiation and activity of osteoblasts and osteoclasts. Determining the relationship between titanium implants and osteocytes may therefore benefit our understanding of the process of osseointegration. Purpose The aim of this study was to visualize the ultrastructural relationship between osteocytes and the titanium implant surface following osseointegration in vivo. Materials and Methods Titanium implants were placed in the maxillary molar regions of eight female Sprague Dawley rats, 3 months old. The animals were sacrificed 8 weeks after implantation, and undecalcified tissue sections were prepared. Resin-cast samples were subsequently acid-etched with 37% phosphoric acid prior to examination using scanning electron microscopy. Results Compared with mature bone, where the osteocytes were arranged in an ordered fashion, the osteocytes appeared less organized in the newly formed bone around the titanium implant. Further, a layer of mineralization with few organic components was observed on the implant surface. This study shows for the first time that osteocytes and their dendrites are directly connected with the implant surface. Conclusions: This study shows the direct anchorage of osteocytes via dendritic processes to a titanium implant surface in vivo. This suggests an important regulatory role for osteocytes and their lacunar-canalicular network in maintaining long-term osseointegration.
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Study design Retrospective validation study. Objectives To propose a method to evaluate, from a clinical standpoint, the ability of a finite-element model (FEM) of the trunk to simulate orthotic correction of spinal deformity and to apply it to validate a previously described FEM. Summary of background data Several FEMs of the scoliotic spine have been described in the literature. These models can prove useful in understanding the mechanisms of scoliosis progression and in optimizing its treatment, but their validation has often been lacking or incomplete. Methods Three-dimensional (3D) geometries of 10 patients before and during conservative treatment were reconstructed from biplanar radiographs. The effect of bracing was simulated by modeling displacements induced by the brace pads. Simulated clinical indices (Cobb angle, T1–T12 and T4–T12 kyphosis, L1–L5 lordosis, apical vertebral rotation, torsion, rib hump) and vertebral orientations and positions were compared to those measured in the patients' 3D geometries. Results Errors in clinical indices were of the same order of magnitude as the uncertainties due to 3D reconstruction; for instance, Cobb angle was simulated with a root mean square error of 5.7°, and rib hump error was 5.6°. Vertebral orientation was simulated with a root mean square error of 4.8° and vertebral position with an error of 2.5 mm. Conclusions The methodology proposed here allowed in-depth evaluation of subject-specific simulations, confirming that FEMs of the trunk have the potential to accurately simulate brace action. These promising results provide a basis for ongoing 3D model development, toward the design of more efficient orthoses.
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One hundred seventy-six consecutive patients treated with IV tissue plasminogen activator (tPA) for acute ischemic stroke were examined prospectively, and orolingual angioedema was found in nine (5.1%; 95% CI 2.3 to 9.5). The reaction was typically mild, transient, and contralateral to the ischemic hemisphere. Risk of angioedema was associated with angiotensin-converting enzyme inhibitors (relative risk [RR] 13.6; 95% CI 3.0 to 62.7) and signs on initial CT of ischemia in the insular and frontal cortex (RR 9.1; 95% CI 1.4 to 30.0).