991 resultados para 154-928
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The therapeutic effects induced by serotonin-selective reuptake inhibitor (SSRI) antidepressants are initially triggered by blocking the serotonin transporter and rely on long-term adaptations of pre- and post-synaptic receptors. We show here that long-term behavioral and neurogenic SSRI effects are abolished after either genetic or pharmacological inactivation of 5-HT(2B) receptors. Conversely, direct agonist stimulation of 5-HT(2B) receptors induces an SSRI-like response in behavioral and neurogenic assays. Moreover, the observation that (i) this receptor is expressed by raphe serotonergic neurons, (ii) the SSRI-induced increase in hippocampal extracellular serotonin concentration is strongly reduced in the absence of functional 5-HT(2B) receptors and (iii) a selective 5-HT(2B) agonist mimics SSRI responses, supports a positive regulation of serotonergic neurons by 5-HT(2B) receptors. The 5-HT(2B) receptor appears, therefore, to positively modulate serotonergic activity and to be required for the therapeutic actions of SSRIs. Consequently, the 5-HT(2B) receptor should be considered as a new tractable target in the combat against depression.
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This paper is a discussion of the use of the SOLO (Structure of Observed Learning Outcomes) Taxonomy (Biggs & Collis, 1982, 1989; Biggs, 1991, 1992a, 1992b; Boulton‐Lewis, 1992, 1994) as a means of developing and assessing higher order thinking in Higher Education. It includes a summary of the research into its use to date as an instrument to find out what students know and believe about their own learning, to assess entering knowledge in a discipline, to present examples of structural organization of knowledge in a discipline, to provide models of levels of desired learning outcomes, and in particular to assess learning outcomes. A proposal is made for further research.
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We implemented six different boarding strategies (Wilma, Steffen, Reverse Pyramid, Random, Blocks and By letter) in order to investigate boarding times for Boeing 777 and Airbus 380 aircraft. We also introduce three new boarding methods to find the optimum boarding strategy. Our models explicitly simulate the behaviour of groups of people travelling together and we explicitly simulate the timing to store their luggage as part of the boarding process. Results from the simulation demonstrates the Reverse Pyramid method is the best boarding method for Boeing 777, and the Steffen method is the best boarding method for Airbus 380. For the new suggested boarding methods, aisle first boarding method is the best boarding strategy for Boeing 777 and row arrangement method is the best boarding strategy for Airbus 380. Overall best boarding strategy is aisle first boarding method for Boeing 777 and Steffen method for Airbus 380.
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Purpose:Over the past decade, corneal nerve morphology and corneal sensation threshold have been explored as potential surrogate markers for the evaluation of diabetic neuropathy. We present the baseline findings of a Longitudinal Assessment of Neuropathy in Diabetes using novel ophthalmic Markers (LANDMark). Methods:The LANDMark Study is a 5-year, two-site, natural history (observational) study of individuals with Type 1 diabetes stratified into those with (T1W) and without (T1WO) neuropathy according to the Toronto criteria, and control subjects. All study participants undergo detailed annual assessment of neuropathy including corneal nerve parameters measured using corneal confocal microscopy and corneal sensitivity measured using non-contact corneal esthesiometry. Results:396 eligible individuals (208 in Brisbane and 188 in Manchester) were assessed: 76 T1W, 166 T1WO and 154 controls. Corneal sensation threshold (mbars) was significantly higher in T1W (1.0 ± 1.1) than T1WO (0.7 ± 0.7) and controls (0.6 ± 0.4) (P=0.002); post-hoc analysis (PHA) revealed no difference between T1WO and controls (Tukey HSD, P=0.502). Corneal nerve fiber length (mm/mm2) (CNFL) was lower in T1W (13.8 ± 6.4) than T1WO (19.1 ± 5.8) and controls (23.2 ± 6.3) (P<0.001); PHA revealed CNFL to be lower in T1W than T1WO, and lower in both of these groups than controls (P<0.001). Corneal nerve branch density (branches/mm2) (CNBD) was significantly lower in T1W (40 ± 32) than T1WO (62 ± 37) and controls (83 ± 46) (P<0.001); PHA showed CNBD was lower in T1W than T1WO, and lower in both groups than controls (P<0.001). Alcohol and cigarette consumption did not differ between groups, although age, BMI, BP, waist circumference, HbA1c, albumin-creatinine ratio, and cholesterol were slightly greater in T1W than T1WO (p<0.05). Some site differences were observed. Conclusions:The LANDMark baseline findings confirm that corneal sensitivity and corneal nerve morphometry can detect differences in neuropathy status in individuals with Type 1 diabetes and healthy controls. Corneal nerve morphology is significantly abnormal even in diabetic patients ‘without neuropathy’ compared to control participants. Results of the longitudinal trial will assess the capability of these tests for monitoring change in these parameters over time as potential surrogate markers for neuropathy.
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Introduction The risk for late periprosthetic fractures is higher in patients treated for a neck of femur fracture compared to those treated for osteoarthritis. It has been hypothesised that osteopenia and consequent decreased stiffness of the proximal femur are responsible for this. We investigated if a femoral component with a bigger body would increase the torque to failure in a biaxially loaded composite sawbone model. Method A biomechanical composite sawbone model was used. Two different body sizes (Exeter 44-1 vs 44-4) of a polished tapered cemented stem were implanted by an experienced surgeon, in 7 sawbones each and loaded at 40 deg/s internal rotation until failure. Torque to fracture and fracture energy were measured using a biaxial materials testing device (Instron 8874). Data are non-parametric and tested with Mann-Whitney U-test. Results The mean torque load to fracture was 154.1 NM (SD 4.4) for the 44-1 stem and 229 NM (SD10.9) for the 44-4 stem (p = 0.01). The mean fracture energy was 9.6 J (SD1.2) for the 44-1 stem and 17.2 J (SD2.0) for the 44-4 stem (p = 0.14). Conclusion the use of a large body polished tapered cemented stem for neck of femur fractures increases the torque to failure in a biomechanical model and therefore is likely to reduce late periprosthetic fracture risk in this vulnerable cohort.
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Background. Escherichia coli O25b:H4-ST131 represents a predominant clone of multidrug-resistant uropathogens currently circulating worldwide in hospitals and the community. Urinary tract infections (UTIs) caused by E. coli ST131 are typically associated with limited treatment options and are often recurrent. Methods. Using established mouse models of acute and chronic UTI, we mapped the pathogenic trajectory of the reference E. coli ST131 UTI isolate, strain EC958. Results. We demonstrated that E. coli EC958 can invade bladder epithelial cells and form intracellular bacterial communities early during acute UTI. Moreover, E. coli EC958 persisted in the bladder and established chronic UTI. Prophylactic antibiotic administration failed to prevent E. coli EC958–mediated UTI. However, 1 oral dose of a small-molecular-weight compound that inhibits FimH, the type 1 fimbriae adhesin, significantly reduced bacterial colonization of the bladder and prevented acute UTI. Treatment of chronically infected mice with the same FimH inhibitor lowered their bladder bacterial burden by >1000-fold. Conclusions. In this study, we provide novel insight into the pathogenic mechanisms used by the globally disseminated E. coli ST131 clone during acute and chronic UTI and establish the potential of FimH inhibitors as an alternative treatment against multidrug-resistant E. coli.
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Background This study reviewed the clinical presentation, cytologic findings and the immunophenotype of 69 Merkel Cell Carcinoma (MCC) cases sampled by FNA. Methods Demographic and clinical data, the cytology findings and results of ancillary testing were reviewed. Results Median patient age was 78 years (37 – 104) with a 1:1.8 female to male ratio. The most common FNA sites sampled included lymph nodes in the neck, the axillary region, the inguinal region and the parotid gland. Most patients had a history of MCC (68%) &/or non-MCC malignancy (70%). The common cytologic pattern was a cellular smear with malignant cells arranged in a dispersed pattern with variable numbers of disorganised groups of cells. Cytoplasm was scant or absent and nuclei showed mild to moderate anisokaryosis, stippled chromatin, inconspicuous nucleoli and nuclear molding. Numerous apoptotic bodies were often present. Cell block samples (28 cases) were usually positive for cytokeratins in a perinuclear dot pattern, including 88% of cases with CK20 positivity. CD56 was the most sensitive (95%) neuroendocrine marker on cell blocks and was also positive with flow cytometry in 9 cases tested. Conclusions MCC is most commonly seen in FNA specimens from the head and neck of elderly patients, often with a history of previous skin lesions. Occasional cases present in younger patients and some may be mistaken for other round blue cell tumors, such as lymphoma. CD 56 may be a useful marker in cell block preparations and in flow cytometric analysis of MCC.
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PURPOSE Every health care sector including hospice/palliative care needs to systematically improve services using patient-defined outcomes. Data from the national Australian Palliative Care Outcomes Collaboration aims to define whether hospice/palliative care patients' outcomes and the consistency of these outcomes have improved in the last 3 years. METHODS Data were analysed by clinical phase (stable, unstable, deteriorating, terminal). Patient-level data included the Symptom Assessment Scale and the Palliative Care Problem Severity Score. Nationally collected point-of-care data were anchored for the period July-December 2008 and subsequently compared to this baseline in six 6-month reporting cycles for all services that submitted data in every time period (n = 30) using individual longitudinal multi-level random coefficient models. RESULTS Data were analysed for 19,747 patients (46 % female; 85 % cancer; 27,928 episodes of care; 65,463 phases). There were significant improvements across all domains (symptom control, family care, psychological and spiritual care) except pain. Simultaneously, the interquartile ranges decreased, jointly indicating that better and more consistent patient outcomes were being achieved. CONCLUSION These are the first national hospice/palliative care symptom control performance data to demonstrate improvements in clinical outcomes at a service level as a result of routine data collection and systematic feedback.
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Background Ambulance professionals often address conflicts between ethical values. As individuals’ values represent basic convictions of what is right or good and motivate behaviour, research is needed to understand their value profiles. Objectives To translate and adapt the Managerial Values Profile to Spanish and Swedish, and measure the presence of utilitarianism, moral rights and/or social justice in ambulance professionals’ value profiles in Spain and Sweden. Methods The instrument was translated and culturally adapted. A content validity index was calculated. Pilot tests were carried out with 46 participants. Ethical considerations This study conforms to the ethical principles for research involving human subjects and adheres to national laws and regulations concerning informed consent and confidentiality. Findings Spanish professionals favoured justice and Swedish professionals’ rights in their ambulance organizations. Both countries favoured utilitarianism least. Gender differences across countries showed that males favoured rights. Spanish female professionals favoured justice most strongly of all. Discussion Swedes favour rights while Spaniards favour justice. Both contexts scored low on utilitarianism focusing on total population effect, preferring the opposite, individualized approach of the rights and justice perspectives. Organizational investment in a utilitarian perspective might jeopardize ambulance professionals’ moral right to make individual assessments based on the needs of the patient at hand. Utilitarianism and a caring ethos appear as stark opposites. However, a caring ethos in its turn might well involve unreasonable demands on the individual carer’s professional role. Since both the justice and rights perspectives portrayed in the survey mainly concern relationship to the organization and peers within the organization, this relationship might at worst be given priority over the equal treatment and moral rights of the patient. Conclusion A balanced view on ethical perspectives is needed to make professionals observant and ready to act optimally – especially if these perspectives are used in patient care. Research is needed to clarify how justice and rights are prioritized by ambulance services and whether or not these organization-related values are also implemented in patient care.
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Objective Resilience is 1 of several factors that are thought to contribute to outcome following mild traumatic brain injury (mTBI). This study explored the predictors of the postconcussional syndrome (PCS) symptoms that can occur following mTBI. We hypothesized that a reported recent mTBI and lower psychological resilience would predict worse reported PCS symptomatology. Method 233 participants completed the Neurobehavioral Symptom Inventory (NSI) and the Brief Resilience Scale (BRS). Three NSI scores were used to define PCS symptomatology. A total of 35 participants reported an mTBI (as operationally defined by the World Health Organization) that was sustained between 1 and 6 months prior to their participation (positive mTBI history); the remainder reported having never had an mTBI. Results Regression analyses revealed that a positive reported recent mTBI history and lower psychological resilience were significant independent predictors of reported PCS symptomatology. These results were found for the 3 PCS scores from the NSI, including using a stringent caseness criterion, p < .05. Demographic variables (age and gender) were not related to outcome, with the exception of education in some analyses. Conclusion The results demonstrate that: (a) both perceived psychological resilience and mTBI history play a role in whether or not PCS symptoms are experienced, even when demographic variables are considered, and; (b) of these 2 variables, lower perceived psychological resilience was the strongest predictor of PCS-like symptomatology.
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Diagnosis of articular cartilage pathology in the early disease stages using current clinical diagnostic imaging modalities is challenging, particularly because there is often no visible change in the tissue surface and matrix content, such as proteoglycans (PG). In this study, we propose the use of near infrared (NIR) spectroscopy to spatially map PG content in articular cartilage. The relationship between NIR spectra and reference data (PG content) obtained from histology of normal and artificially induced PG-depleted cartilage samples was investigated using principal component (PC) and partial least squares (PLS) regression analyses. Significant correlation was obtained between both data (R2 = 91.40%, p<0.0001). The resulting correlation was used to predict PG content from spectra acquired from whole joint sample, this was then employed to spatially map this component of cartilage across the intact sample. We conclude that NIR spectroscopy is a feasible tool for evaluating cartilage contents and mapping their distribution across mammalian joint
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Limited treatment options for Castration Resistant Prostate Cancer (CRPC) still remain a major challenge. Despite therapeutic advances, most patients with malignant PCa have a poor prognosis. Since the year 2000, we have rapidly expanded our understanding of the molecular mechanisms underlying CRPC and this has led to an unprecedented number of new drug approvals within a short span of time. Recently, four new agents namely Abiraterone Acetate, Enzalutamide, Cabazitaxel, and Radium-223 have been shown to be effective in the post-chemotherapy setting in CRPC. The continued dependency of CRPC on androgen synthesis has seen the development of a number of new anti-androgen therapies, with abiraterone acetate and Enzalutamide being the most promising discoveries. Immunotherapeutic approaches have also found their niche in PCa with Sipuleucel-T shown to be effective in minimally asymptomatic CRPC. Research focussed on bone-targeting therapies has witnessed the arrival of promising new drugs with Denosumab and Radium-223 displaying improved survival of patients with CRPC. This review briefly discusses the findings and limitations from ongoing and completed clinical trials of novel treatments and regimens. In addition, potential mechanisms of therapy resistance and future challenges are discussed.