852 resultados para Clustering and objective measures


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Background and Objective: Oral mucositis is a dose-limiting and painful side effect of radiotherapy (RT) and/or chemotherapy in cancer patients. The purpose of the present study was to analyze the effect of different protocols of laser phototherapy (LPT) on the grade of mucositis and degree of pain in patients under RT. Patients and Methods: Thirty-nine patients were divided into three groups: G1, where the irradiations were done three times a week using low power laser; G2, where combined high and low power lasers were used three time a week; and G3, where patients received low power laser irradiation once a week. The low power LPT was done using an InGaAlP laser (660 nm/40 mW/6 J cm(-2)/0.24 J per point). In the combined protocol, the high power LPT was done using a GaAlAs laser (808 nm, 1 W/cm(2)). Oral mucositis was assessed at each LPT session in accordance to the oral-mucositis scale of the National Institute of the Cancer-Common Toxicity criteria (NIC-CTC). The patient self-assessed pain was measured by means of the visual analogue scale. Results: All protocols of LPT led to the maintenance of oral mucositis scores in the same levels until the last RT session. Moreover, LPT three times a week also maintained the pain levels. However, the patients submitted to the once a week LPT had significant pain increase; and the association of low/high LPT led to increased healing time. Conclusions: These findings are desired when dealing with oncologic patients under RT avoiding unplanned radiation treatment breaks and additional hospital costs. Lasers Surg.Med. 41:264-270,2009. (C) 2009Wiley-Liss, Inc.

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Background and Objective: Substance P may play a role in the pathogenesis of periodontal disease; however, its mechanisms of modulation are not clear. This study evaluated the effect of two concentrations of Substance P on the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in cultured human gingival fibroblasts. Materials and Methods: Fibroblasts were stimulated for 48 h with 10(-4) or 10(-9) m Substance P; untreated fibroblasts served as controls. The expression of MMP-1, -2, -3, -7 and -11 and of TIMP-1 and -2 was evaluated using real-time polymerase chain reaction and western blotting. Resulsts: There was a significant, concentration-dependent stimulatory effect of Substance P on MMP-1, -2, -3 and -7 and TIMP-2 gene expression (p < 0.05), and a probable effect on MMP-11 (p = 0.06). At the higher concentration (10(-4) m Substance P), MMP-1, -2, -3, -7 and -11 and TIMP-2 showed the greatest up-regulation; at the lower concentration (10(-9) (M) Substance P), MMP-1, -3 and -7 and TIMP-2 exhibited diminished up-regulation, with MMP-2 and -11 showing down-regulation (p < 0.05). Expression of TIMP-1 was not affected by Substance P (p > 0.05). Western blotting confirmed that Substance P up-regulated MMP-1, -2, -3 and -11 and TIMP-2. MMP-1, -3 and -11 and TIMP-2 showed greater up-regulation at the higher Substance P concentration and diminished up-regulation at the lower concentration. MMP-2 was up-regulated to a similar degree at both Substance P concentrations. Conclusion: In gingival fibroblast cells, Substance P at the higher concentration (10(-4) m) induced greater up-regulation of MMP-1, -3 and -11 and TIMP-2 expression, but at the lower concentration (10(-9) (M)) induced diminished up-regulation, which may represent a mechanism for modulating periodontal breakdown.

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Evaluative learning theory states that affective learning, the acquisition of likes and dislikes, is qualitatively different from relational learning, the learning of predictive relationships among stimuli. Three experiments tested the prediction derived from evaluative learning theory that relational learning, but not affective learning, is affected by stimulus competition by comparing performance during two conditional stimuli, one trained in a superconditioning procedure and the other in a blocking procedure. Ratings of unconditional stimulus expectancy and electrodermal responses indicated stimulus competition in relational learning. Evidence for stimulus competition in affective learning was provided by verbal ratings of conditional stimulus pleasantness and by measures of blink startle modulation. Taken together, the present experiments demonstrate stimulus competition in relational and affective learning, a result inconsistent with evaluative learning theory. (C) 2001 Academic Press.

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Objective To obtain information on tick paralysis in dogs, including the nature of disease, host signalment, tick-host relationship, treatment, disease progression and recovery, and preventive measures. Design A prospective survey of 577 dogs affected by tick paralysis was conducted during 1998. Forty-two veterinary clinics along the eastern coast of Australia were instructed to complete survey forms for the first 15 dogs that presented with tick paralysis during September to November. Results Five percent of dogs died from tick paralysis. Younger dogs were more likely to survive. Long coat length was associated with a greater tick burden but not greater tick size, whereas coat thickness had no bearing on either. Dogs with mild disease recovered more quickly from tick paralysis. Respiratory and gait scores reflected disease severity and were good prognostic indicators. The size of the tick did not reflect the severity of the clinical condition it induced in the host. No method of tick removal or in situ treatment improved recovery time or reduced mortality. However, the time spent in hospital was significantly less for dogs from which the live tick was manually removed. Inspiratory strider. evident in some dogs with tick paralysis, was not related to tick attachment on the neck. The use of acepromazine maleate or dexamethasone did not reduce recovery time or mortality. Increasing the dose of tick antitoxin serum (TAS) above 0.1 mL/kg had no effect on mortality or recovery time. Dogs with severe disease that received an additional dose of TAS were significantly less likely to survive. Subcutaneous use of TAS at the site of tick attachment was of no benefit in reducing mortality or time to initial clinical improvement. A registered preventative product had not been used on the majority of dogs. Clipping the coat to search for ticks did not reduce mortality. Conclusions Therapy needs to address cardiopulmonary dysfunction that may be due directly to the effect of tick toxin and not just respiratory compromise caused by progressive respiratory muscle failure.

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A multivariate model using hierarchical clustering and discriminant analysis is used to identify clusters of community opportunity and community vulnerability across Australia's mega metropolitan regions, Variables used in the model measure aspects of structural economic change, occupational change, human capital, income, unemployment, family/household disadvantage, and housing stress. A nine-cluster solution is used to categorise communities across metropolitan space. Significant between-city variations in the incidence of these clusters of opportunity and vulnerability are apparent, suggesting the emergence of marked differentiation between Australia's mega metropolitan regions in their adjustments to changing economic and social conditions. JEL classification: C49, R11, R12.

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Riparian vegetation can be an effective measure for preventing degradation of streambanks and riparian areas. However, riparian revegetation imposes large costs on landholders associated with tree establishment and removal of land from cropping, while providing benefits to downstream landholders, fishers, the local community and environmentalists. Appropriate policy instruments are required to promote sustainable and balanced use of riparian zones. This article analyses the capacity of existing legislation and other instruments to promote restoration of degraded riparian zones on private land. The role of legislation. economic instruments, community engagement and extension programs, in persuading landholders to revegetate riparian areas and improve riparian vegetation cover; is examined in the context ofa small degraded catchment in an intensive farming area in tropical north Queensland. It is found that while legislation and regulations can control undesirable modification of riparian areas, in general they are unable to make a useful contribution to restoration of these areas; incentives and assistance measures appear to offer greater potential.

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Genetic and environmental sources of covariation among the P3(00) and online performance elicited in a delayed-response working memory task, and psychometric IQ assessed by the multidimensional aptitude battery, were examined in an adolescent twin sample. An association between frontal P3 latency and task performance (phenotypic r = -0.33; genotypic r = -0.49) was indicated, with genes (i.e. twin status) accounting for a large part of the covariation ( > 70%). In contrast, genes influencing P3 amplitude mediated only a small part (2%) of the total genetic variation in task performance. While task performance mediated 15% of the total genetic variation in IQ (phenotypic r = 0.22; genotypic r = 0.39) there was no association between P3 latency and IQ or P3 amplitude with IQ. The findings provide some insight into the inter-relationships among psychophysiological, performance and psychometric measures of cognitive ability, and provide support for a levels-of-processing genetic model of cognition where genes act on specific sub-components of cognitive processes.

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The most recent account of Bueckeburgichnus maximus Kuhn 1958, a distinctive theropod dinosaur track from the Lower Cretaceous of Germany, is shown to be based on a referred specimen mistakenly identified as the holotype and the correct name of this taxon is deemed to be Megalosauripus maximus (Kuhn 1958). This minor revision has important consequences for nomenclature of the many European, Asian, North American and Australian dinosaur tracks attributed to megalosaurian theropods. Many of those tracks were named Megalosauripus, but that name has a confusing multiplicity of meanings and it should be restricted to the highly characteristic dinosaur track formerly identified as Bueckeburgichnus. Other tracks named "Megalosauripus”; (in its several other senses) will require new nomenclature, despite their extensive and repeated revision since 1996. It is recommended that future revision should adopt conventions of the International Code of Zoological Nomenclature. Although previous revisions expressed an intention to adhere to those conventions, these were not put into practice, with the unfortunate result of multiplying the problems that surround the nomenclature of megalosaur tracks. Introduction of the name Megalosauripus maximus (Kuhn 1958) eliminates those burgeoning problems and permits the introduction of new and objective nomenclature for presumed megalosaur tracks.

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This study investigated the influence of a concurrent cognitive task on the compensatory stepping response in balance-impaired elders and the attentional demand of the stepping response. Kinetic, kinematic and neuromuscular measures of a forward recovery step were investigated in 15 young adults, 15 healthy elders and 13 balance-impaired elders in a single task (postural recovery only) and dual task (postural recovery and vocal reaction time task) situation. Results revealed that reaction times were longer in all subjects when performed concurrently with a compensatory step, they were longer for a step than an in-place response and longer for balance-impaired older adults compared with young adults. An interesting finding was that the latter group difference may be related to prioritization between the two tasks rather than attentional demand, as the older adults completed the step before the reaction time, whereas the young adults could perform both concurrently. Few differences in step characteristics were found between tasks, with the most notable being a delayed latency and reduced magnitude of the early automatic postural response in healthy and balance-impaired elders with a concurrent task. (C) 2002 Elsevier Science B.V. All rights reserved.

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Background and Purpose Previous research regarding the symmetry of trans-tibial amputees has examined weight distribution and various gait parameters between prosthetic and sound limbs. However, to date, no known research has determined if asymmetry is present in the strength of the hip abductor muscles or if correlations exist between these categories of symmetry. The purpose of the present study was, therefore, to document asymmetry present in stance, strength and gait measures, and to determine the relationship between these variables. Method Twenty-three elderly, unilateral trans-tibial amputees stood on two adjacent forceplates whilst the weight distribution and standard deviation (SD) of the anterior-posterior and the medio-lateral centre of pressure excursion (COPE) under each limb was recorded during four 40 s trials: quiet stance (QS), with eyes open and eyes closed; and even stance (ES), with eyes open and eyes closed. Gait measures (velocity, cadence, step and stride lengths, stance:swing ratio and period of double support) over 10 m of fast, yet safe walking and measures of the strength of hip abductor muscles were also obtained by use of a stride analyser and a dynamometer, respectively. Results No significant differences were found between QS and ES measures. However, significantly more weight was taken on the sound limb than on the amputated limb. Notably, more anterior-posterior movement occurred under the sound limb than the amputated limb, with this becoming more apparent with the eyes closed. Movement in the medio-lateral direction was found to be the same between sides. No differences in muscle strength or gait measures between limbs were demonstrated. However. strong hip abductor muscles were correlated with increased weight-bearing on the amputated limb, improved gait parameters and reduced medio-lateral COPE under the amputated limb. Conclusions This research confirms the asymmetrical nature of amputee stance and demonstrates symmetry of strength and gait measures between limbs. The correlations between hip abductor muscle strength, weight distribution and gait measures illustrates the importance of pre- and postoperative training of these muscles. Copyright © 2002 Whurr Publishers Ltd.

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Eph receptor tyrosine kinases and ephrins regulate morphogenesis in the developing embryo where they effect adhesion and motility of interacting cells. Although scarcely expressed in adult tissues, Eph receptors and ephrins are overexpressed in a range of tumours. In malignant melanoma, increased Eph and ephrin expression levels correlate with metastatic progression. We have examined cellular and biochemical responses of EphA3-expressing melanoma cell lines and human epithelial kidney 293T cells to stimulation with polymeric ephrin-A5 in solution and with surfaces of defined ephrin-A5 densities. Within minutes, rapid reorganisation of the actin and myosin cytoskeleton occurs through activation of RhoA, leading to the retraction of cellular protrusions, membrane blebbing and detachment, but not apoptosis. These responses are inhibited by monomeric ephrin-A5, showing that receptor clustering is required for this EphA3 response. Furthermore, the adapter CrkII, which associates with tyrosine-phosphorylated EphA3 in vitro, is recruited in vivo to ephrin-A5-stimulated EphA3. Expression of an SH3-domain mutated CrkII ablates cell rounding, blebbing and detachment. Our results suggest that recruitment of CrkII and activation of Rho signalling are responsible for EphA3-mediated cell rounding, blebbing and de-adhesion, and that ephrin-A5-mediated receptor clustering and EphA3 tyrosine kinase activity are essential for this response.

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The use of human brain tissue obtained at autopsy for neurochemical, pharmacological and physiological analyses is reviewed. RNA and protein samples have been found suitable for expression profiling by techniques that include RT-PCR, cDNA microarrays, western blotting, immunohistochemistry and proteomics. The rapid development of molecular biological techniques has increased the impetus for this work to be applied to studies of brain disease. It has been shown that most nucleic acids and proteins are reasonably stable post-mortem. However, their abundance and integrity can exhibit marked intra- and intercase variability, making comparisons between case-groups difficult. Variability can reveal important functional and biochemical information. The correct interpretation of neurochemical data must take into account such factors as age, gender, ethnicity, medicative history, immediate ante-mortem status, agonal state and post-mortem and post-autopsy intervals. Here we consider issues associated with the sampling of DNA, RNA and proteins using human autopsy brain tissue in relation to various ante- and post-mortem factors. We conclude that valid and practical measures of a variety of parameters may be made in human brain tissue, provided that specific factors are controlled.

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Background: Congestive heart failure (CHF) is an increasingly prevalent poor-prognosis condition for which effective interventions are available. It is -therefore important to determine the extent to which patients with CHF receive appropriate care in Australian hospitals and identify ways for improving suboptimal care, if it exists. Aim: To evaluate the quality of in-hospital acute care of patients with CHF using explicit quality indicators based on published guidelines. Methods: A retrospective case note review was -performed, involving 216 patients admitted to three teaching hospitals in Brisbane, Queensland, Australia, between October 2000 and April 2001. Outcome measures were process-of-care quality -indicators calculated as proportions of all, or strongly -eligible (ideal), patients who received -specific interventions. Results: Assessment of underlying causes and acute precipitating factors was undertaken in 86% and 76% of patients, respectively, and objective evaluation of left ventricular function was performed in 62% of patients. Prophylaxis for deep venous thrombosis (DVT) was used in only 29% of ideal patients. Proportions of ideal patients receiving pharmacological treatments at discharge were: (i) angiotensin--converting enzyme inhibitors (ACEi) (82%), (ii) target doses of ACEi (61%), (iii) alternative vasodilators in patients ineligible for ACEi (20%), (iv) beta-blockers (40%) and (v) warfarin (46%). Conclusions: Opportunities exist for improving quality of in-hospital care of patients with CHF, -particularly for optimal prescribing of: (i) DVT prophylaxis, (ii) ACEi, (iii) second-line vasodilators, (iv) beta-blockers and (v) warfarin. More research is needed to identify methods for improving quality of in-hospital care.

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Background: The heavy usage of coxibs in Australia far outstrips the predicted usage that was based on the treatment of patients with risk factors for upper gastro-intestinal adverse events from conventional anti--inflammatory agents. This raises questions regarding the appropriateness of prescribing. Aims: To determine: (i) the relationship between prescriptions for cyclooxygenase 2 (COX-2) inhibitors and objective evidence of inflammatory arthritis, (ii) prior experience with paracetamol and/or conventional non-steroidal anti-inflammatory drugs (NSAIDs), and (iii) contraindications to the use of NSAIDs. Methods: Drug utilization evaluation and rheumato-logical assessment was conducted on 70 consecutive patients admitted on COX-2 inhibitors to a 480-bed metropolitan hospital. The main outcome measures were: the indication for COX-2 inhibitor; objective -evidence of inflammatory arthritis; previous trial of -paracetamol or conventional NSAIDs; and patient -satisfaction. Results: Only 11 patients (16%) had symptoms or signs of an inflammatory arthropathy, and met Pharmaceut-ical Benefits Schedule criteria for prescribing a COX-2 inhibitor. Fifty-nine patients (84%) had chronic osteo-arthritis, degenerative spinal disease, injury or malignancy, without overt active inflammation. Fourteen patients (20%) had trialled regular paracetamol prior to using any NSAID treatment. Conventional NSAIDs had been previously used by 51 patients (73%). Eleven patients (16%) reported previous adverse gastrointestinal effects from conventional NSAIDs. On the basis of significant renal impairment (creatinine clearance 5/10). Conclusions: Drug utilization data indicate that COX-2 inhibitors are frequently used first line for degenerative osteoarthritis in the absence of overt inflammation, without prior adequate trial of paracetamol and with disregard for the cautions and contraindications of these agents. These findings may explain the unprecedented Pharmaceutical Benefits Schedule expenditure on COX-2 inhibitors in Australia.

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The aim of this tudy was to evaluate corporal and testicular development in wild boars (Sus scrofa scrofa) from birth to 12 months of age, evaluating body weight, biometric testicular parameters, and gonadosomatic index. Thirty-nine male wild boars from a commercial farm licensed by IBAMA were used in the study. The animals were weighed and assigned to 13 experimental groups. The testes were recovered through unilateral orchiectomy, weighed on an analytical balance and measured for length, width and thickness. Body weight and testicular measures increased with the age, up to 12 months, and were more accelerated in the first and ninth months. Initially the testicular growth pattern, between zero and nine months, followed the body growth, and the gonadosomatic index varied from 0.07 to 0.09%. Between 9 and 11 months, the testicular growth was superior to the body growth, and the gonadosomatic index varied from 0.09 to 0.16%. Finally, after 11 months of age, testicular and body growth had a similar behavior. In conclusion, body weight, testicular biometry, and gonadosomatic index development accelerated in the ninth month.