973 resultados para 6-51


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BACKGROUND: Transcatheter closure of patent foramen ovale (PFO) has rapidly evolved as the preferred management strategy for the prevention of recurrent cerebrovascular events in patients with cryptogenic stroke and presumed paradoxical embolus. There is limited outcome data in patients treated with this therapy particularly for the newer devices. METHODS: Data from medical records, catheter, and echocardiography databases on 70 PFO procedures performed was collected prospectively. RESULTS: The cohort consisted of 70 patients (mean age 43.6 years, range 19 to 77 years), of whom 51% were male. The indications for closure were cryptogenic cerebrovascular accident (CVA) or transient ischemic attack (TIA) in 64 (91%) and peripheral emboli in two (2.8%) patients and cryptogenic ST-elevation myocardial infarction in one (1.4%), refractory migraine in one (1.4%), decompression sickness in one (1.4%), and orthodeoxia in one (1.4%) patient, respectively. All patients had demonstrated right-to-left shunting on bubble study. The procedures were guided by intracardiac echocardiography in 53%, transesophageal echocardiography in 39%, and the remainder by transthoracic echo alone. Devices used were the Amplatzer PFO Occluder (AGA Medical) (sizes 18-35 mm) in 49 (70%) and the Premere device (St. Jude Medical) in 21 (30%). In-hospital complications consisted of one significant groin hematoma with skin infection. Echocardiographic follow-up at 6 months revealed that most patients had no or trivial residual shunt (98.6%), while one patient (1.4%) had a mild residual shunt. At a median of 11 months' follow-up (range 1 month to 4.3 years), no patients (0%) experienced further CVA/TIAs or paradoxical embolic events during follow-up. CONCLUSION: PFO causing presumed paradoxical embolism can be closed percutaneously with a low rate of significant residual shunting and very few complications. Recurrent index events are uncommon at medium-term (up to 4 years) follow-up.

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BACKGROUND: We aimed to determine the prevalence and associations of refractive error on Norfolk Island. DESIGN: Population-based study on Norfolk Island, South Pacific. PARTICIPANTS: All permanent residents on Norfolk Island aged ≥ 15 years were invited to participate. METHODS: Patients underwent non-cycloplegic autorefraction, slit-lamp biomicroscope examination and biometry assessment. Only phakic eyes were analysed. MAIN OUTCOME MEASURES: Prevalence and multivariate associations of refractive error and myopia. RESULTS: There were 677 people (645 right phakic eyes, 648 left phakic eyes) aged ≥ 15 years were included in this study. Mean age of participants was 51.1 (standard deviation 15.7; range 15-81). Three hundred and seventy-six people (55.5%) were female. Adjusted to the 2006 Norfolk Island population, prevalence estimates of refractive error were as follows: myopia (mean spherical equivalent ≥ -1.0 D) 10.1%, hypermetropia (mean spherical equivalent ≥ 1.0 D) 36.6%, and astigmatism 17.7%. Significant independent predictors of myopia in the multivariate model were lower age (P < 0.001), longer axial length (P < 0.001), shallower anterior chamber depth (P = 0.031) and increased corneal curvature (P < 0.001). Significant independent predictors of refractive error were increasing age (P < 0.001), male gender (P = 0.009), Pitcairn ancestry (P = 0.041), cataract (P < 0.001), longer axial length (P < 0.001) and decreased corneal curvature (P < 0.001). CONCLUSIONS: The prevalence of myopia on Norfolk Island is lower than on mainland Australia, and the Norfolk Island population demonstrates ethnic differences in the prevalence estimates. Given the significant associations between refractive error and several ocular biometry characteristics, Norfolk Island may be a useful population in which to find the genetic basis of refractive error.

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In South and Southeast Asia, postharvest loss causes material waste of up to 66% in fruits and vegetables, 30% in oilseeds and pulses, and 49% in roots and tubers. The efficiency of postharvest equipment directly affects industrial-scale food production. To enhance current processing methods and devices, it is essential to analyze the responses of food materials under loading operations. Food materials undergo different types of mechanical loading during postharvest and processing stages. Therefore, it is important to determine the properties of these materials under different types of loads, such as tensile, compression, and indentation. This study presents a comprehensive analysis of the available literature on the tensile properties of different food samples. The aim of this review was to categorize the available methods of tensile testing for agricultural crops and food materials to investigate an appropriate sample size and tensile test method. The results were then applied to perform tensile tests on pumpkin flesh and peel samples, in particular on arc-sided samples at a constant loading rate of 20 mm min-1. The results showed the maximum tensile stress of pumpkin flesh and peel samples to be 0.535 and 1.45 MPa, respectively. The elastic modulus of the flesh and peel samples was 6.82 and 25.2 MPa, respectively, while the failure modulus values were 14.51 and 30.88 MPa, respectively. The results of the tensile tests were also used to develop a finite element model of mechanical peeling of tough-skinned vegetables. However, to study the effects of deformation rate, moisture content, and texture of the tissue on the tensile responses of food materials, more investigation needs to be done in the future.

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Obese (BMI ≥ 26 kg/m 2; n = 51) and lean (BMI <26 kg/m 2; n = 61) Caucasian patients with severe, familial essential hypertension, were compared with respect to genotype and allele frequencies of a HincII RFLP of the low density lipoprotein receptor gene (LDLR). A similar analysis was performed in obese (n = 28) and lean (n = 68) normotensives. A significant association of the C allele of the T→C variant responsible for this RFLP was seen with obesity (χ 2 = 4.6, P = 0.029) in the hypertensive, but not in the normotensive, group (odds ratio = 3.0 for the CC genotype and 2.7 for CT). Furthermore, BMI tracked with genotypes of this allele in the hypertensives (P = 0.046). No significant genotypic relationship was apparent for plasma lipids. Significant linkage disequilibrium was, moreover, noted between the HincII RFLP and an ApaLI RFLP (χ 2 = 33, P<0.0005) that has previously shown even stronger association with obesity (odds ratio 19.6 for cases homozygous for the susceptibility allele and 15.2 for het-erozygotes). The present study therefore adds to our previous evidence implicating LDLR as a locus for obesity in patients with essential hypertension.

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Essential hypertension is a highly hereditable disorder in which genetic influences predominate over environmental factors. The molecular genetic profiles which predispose to essential hypertension are not known. In rats with genetic hypertension, there is some recent evidence pointing to linkage of renin gene alleles with blood pressure. The genes for renin and antithrombin III belong to a conserved synteny group which, in humans, spans the q21.3-32.3 region of chromosome I and, in rats, is linkage group X on chromosome 13. The present study examined the association of particular human renin gene (REN) and antithrombin III gene (AT3) polymorphisms with essential hypertension by comparing the frequency of specific alleles for each of these genes in 50 hypertensive offspring of hypertensive parents and 91 normotensive offspring of normotensive parents. In addition, linkage relationships were examined in hypertensive pedigrees with multiple affected individuals. Alleles of a REN HindIII restriction fragment length polymorphism (RFLP) were detected using a genomic clone, λHR5, to probe Southern blots of HindIII-cut leucocyte DNA, and those for an AT3 Pstl RFLP were detected by phATIII 113 complementary DNA probe. The frequencies of each REN allele in the hypertensive group were 0.76 and 0.24 compared with 0.74 and 0.26 in the normotensive group. For AT3, hypertensive allele frequencies were 0.49 and 0.51 compared with normotensive values of 0.54 and 0.46. These differences were not significant by χ2 analysis (P > 0.2). Linkage analysis of a family (data from 16 family members, 10 of whom were hypertensive), informative for both markers, without an age-of-onset correction, and assuming dominant inheritance of hypertension, complete penetrance and a disease frequency of 20%, did not indicate linkage of REN with hypertension, but gave a positive, although not significant, logarithm of the odds for linkage score of 0.784 at a recombination fraction of 0 for AT3 linkage to hypertension. In conclusion, the present study could find no evidence for an association of a REN HindIII RFLP with essential hypertension or for a linkage of the locus defined by this RFLP in a family segregating for hypertension. In the case of an AT3 Pstl RFLP, although association analysis was negative, linkage analysis suggested possible involvement (odds of 6:1 in favour) of a gene located near the 1q23 locus with hypertension in one informative family.

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The electrochemical formation of highly porous CuTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane) and CuTCNQF4 (TCNQF4 = 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane) materials was undertaken via the spontaneous redox reaction between a porous copper template, created using a hydrogen bubbling template technique, and an acetonitrile solution containing TCNQ or TCNQF4. It was found that activation of the surface via vigorous hydrogen evolution that occurs during porous copper deposition and TCNQ mass transport being hindered through the porous network of the copper template influenced the growth of CuTCNQ and CuTCNQF4. This approach resulted in the fabrication of a honeycomb layered type structure where the internal walls consist of very fine crystalline needles or spikes. This combination of microscopic and nanoscopic roughness was found to be extremely beneficial for anti-wetting properties where superhydrophobic materials with contact angles as high as 177° were created. Given that CuTCNQ and CuTCNQF4 have shown potential as molecular based electronic materials in the area of switching and field emission, the creation of a surface that is moisture resistant may be of applied interest.

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Background Cancer-related malnutrition is associated with increased morbidity, poorer tolerance of treatment, decreased quality of life, increased hospital admissions, and increased health care costs (Isenring et al., 2013). This study’s aim was to determine whether a novel, automated screening system was a useful tool for nutrition screening when compared against a full nutrition assessment using the Patient-Generated Subjective Global Assessment (PG-SGA) tool. Methods A single site, observational, cross-sectional study was conducted in an outpatient oncology day care unit within a Queensland tertiary facility, with three hundred outpatients (51.7% male, mean age 58.6 ± 13.3 years). Eligibility criteria: ≥18 years, receiving anticancer treatment, able to provide written consent. Patients completed the Malnutrition Screening Tool (MST). Nutritional status was assessed using the PG-SGA. Data for the automated screening system was extracted from the pharmacy software program Charm. This included body mass index (BMI) and weight records dating back up to six months. Results The prevalence of malnutrition was 17%. Any weight loss over three to six weeks prior to the most recent weight record as identified by the automated screening system relative to malnutrition resulted in 56.52% sensitivity, 35.43% specificity, 13.68% positive predictive value, 81.82% negative predictive value. MST score 2 or greater was a stronger predictor of nutritional risk relative to PG-SGA classified malnutrition (70.59% sensitivity, 69.48% specificity, 32.14% positive predictive value, 92.02% negative predictive value). Conclusions Both the automated screening system and the MST fell short of the accepted professional standard for sensitivity (80%) or specificity (60%) when compared to the PG-SGA. However, although the MST remains a better predictor of malnutrition in this setting, uptake of this tool in the Oncology Day Care Unit remains challenging.

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Introduction: Mothers’ sleep during the postpartum period is commonly characterised by bouts of sleep across the night, resulting in low sleep efficiency and daytime sleepiness. Understanding of the nature of mothers’ sleep disruption needs to incorporate indices of both sleep quantity and sleep quality, but objective assessment of sleep disturbance experienced during the first postpartum months has not been investigated in great detail. This longitudinal study aimed to objectively measure mothers’ sleep during the first 18 weeks postpartum, to ascertain the level of sleep disturbance experienced. Method: Eleven mothers (Mean age = 29.82, SD = 4.45) from Australia wore Actiwatch-2 devices for up to 7 days and nights at 6, 12 and 18 weeks postpartum. For each night of recording, a number of sleep bouts were identified. Total sleep time (TST) was calculated as the total number of minutes across the night within these bouts. Sleep efficiency was calculated as the percentage of minutes across the night classified as being part of a sleep bout, with higher scores indicating higher efficiency. Sleep quality captured the efficiency of sleep within sleep bouts, and was calculated as the percentage of epochs classified as sleep within sleep bouts, with higher scores indicating higher sleep quality. Results: At 6 weeks postpartum, mean total sleep time was 420.22 minutes (SD = 50.61). Total sleep time did not significantly differ across the assessment; however there was a trend towards an increase over time. Sleep efficiency increased across the time periods (F(2,10) = 10.30, p = .001), with a significant increase between week 12 and week 18. At 6 weeks postpartum, mean sleep quality was 93.15% (SD = 2.68) and scores did not significantly change across the assessment periods. While there was no relationship between sleep efficiency and sleep quality during weeks 6 and 12, a significant positive relationship was observed at week 18, r2 = .52, p = .013. Conclusions: Within this sample, a low level of disruption was consistently shown within the mothers’ night time sleep bouts. However, overall sleep efficiency suggested a significant proportion of time spent awake between sleep bouts. While TST remained stable over time, overall sleep efficiency improved, suggesting the mothers’ sleep was becoming more consolidated. A single sleep bout a night was not often experienced.

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Exogenous prostacyclin is effective in reducing pulmonary vascular resistance in some forms of human pulmonary hypertension (PH). To explore whether endogenous prostaglandins played a similar role in pulmonary hypertension, we examined the effect of deleting cyclooxygenase (COX)-gene isoforms in a chronic hypoxia model of PH. Pulmonary hypertension, examined by direct measurement of right ventricular end systolic pressure (RVESP), right ventricular hypertrophy (n = 8), and hematocrit (n = 3), was induced by 3 weeks of hypobarichypoxia in wild-type and COX-knockout (KO) mice. RVESP was increased in wild-type hypoxic mice compared with normoxic controls (24.4 ± 1.4 versus 13.8 ± 1.9 mm Hg; n = 8; p < 0.05). COX-2 KO mice showed a greater increase in RVESP following hypoxia (36.8 ± 2.7 mm Hg; p < 0.05). Urinary thromboxane (TX)B2 excretion increased following hypoxia (44.6 ± 11.1 versus 14.7 ± 1.8 ng/ml; n = 6; p < 0.05), an effect that was exacerbated by COX-2 gene disruption (54.5 ± 10.8 ng/ml; n = 6). In contrast, the increase in 6-keto-prostacyclin1α excretion following hypoxia was reduced by COX-2 gene disruption (29 ± 3 versus 52 ± 4.6 ng/ml; p < 0.01). Tail cut bleed times were lower following hypoxia, and there was evidence of intravascular thrombosis in lung vessels that was exacerbated by disruption of COX-2 and reduced by deletion of COX-1. The TXA2/endoperoxide receptor antagonist ifetroban (50 mg/kg/day) offset the effect of deleting the COX-2 gene, attenuating the hypoxia-induced rise in RVESP and intravascular thrombosis. COX-2 gene deletion exacerbates pulmonary hypertension, enhances sensitivity to TXA2, and induces intravascular thrombosis in response to hypoxia. The data provide evidence that endogenous prostaglandins modulate the pulmonary response to hypoxia. Copyright © 2008 by The American Society for Pharmacology and Experimental Therapeutics.

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Aims: To report cancer-specific and health-related quality-of-life outcomes in patients undergoing radical chemoradiation (CRT) alone for oesophageal cancer. Materials and methods: Between 1998 and 2005, 56 patients with oesophageal cancer received definitive radical CRT, due to local disease extent, poor general health, or patient choice. Data from European Organization for Research and Treatment of Cancer quality-of-life questionnaires QLQ-30 and QLQ-OES24 were collected prospectively. Questionnaires were completed at diagnosis, and at 3, 6 and 12 months after CRT where applicable. Results: The median follow-up was 18 months. The median overall survival was 14 months, with a 51, 26 and 13% 1-, 3- and 5-year survival, respectively. At 12 months after treatment there was a significant improvement compared with before treatment with respect to dysphagia and pain. Global health scores were not significantly affected. Conclusions: Considering the relatively short long-term survival for this cohort of patients, maximising the quality of those final months should be very carefully borne in mind from the outset. The health-related quality-of-life data reported herein helps to establish benchmarks for larger evaluation within randomised clinical trials. © 2007 The Royal College of Radiologists.

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This paper presents a review of existing and current developments and the analysis of Hybrid-Electric Propulsion Systems (HEPS) for small fixed-wing Unmanned Aerial Vehicles (UAVs). Efficient energy utilisation on an UAV is essential to its functioning, often to achieve the operational goals of range, endurance and other specific mission requirements. Due to the limitations of the space available and the mass budget on the UAV, it is often a delicate balance between the onboard energy available (i.e. fuel) and achieving the operational goals. One technology with potential in this area is with the use of HEPS. In this paper, information on the state-of-art technology in this field of research is provided. A description and simulation of a parallel HEPS for a small fixed-wing UAV by incorporating an Ideal Operating Line (IOL) control strategy is described. Simulation models of the components in a HEPS were designed in the MATLAB Simulink environment. An IOL analysis of an UAV piston engine was used to determine the most efficient points of operation for this engine. The results show that an UAV equipped with this HEPS configuration is capable of achieving a fuel saving of 6.5%, compared to the engine-only configuration.

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Background: Hydroxyurea (HU), an inhibitor of ribonucleotide reductase, may potentiate the activity of 5-fluorouracil (5-FU) and folinic acid (FA) by reducing the deoxyribonucleotide pool available for DNA synthesis and repair. However as HU may inhibit the formation of 5-fluoro-2-deoxyuridine-5- monophosphate (FdUMP), one of the principal active metabolites of 5-FU, the scheduling of HU may be critical. In vitro experiments suggest that administration of HU following 5-FU, maintaining the concentration in the region of I mM for six or more hours, significantly enhances the efficacy of 5-FU. Patients and methods: 5-FU/FA was given as follows: days 1 and 2 - FA 250 mg/m 2 (max. 350 mg) over two hours followed by 5-FU 400 mg/m 2 by intravenous bolus (ivb) over 15 minutes and subsequently 5-FU 400 mg/m 2 infusion (ivi) over 22 hours. HU was administered on day 3 immediately after the 5-FU with 3 g ivb over 15 minutes followed by 12 g ivi over 12 hours. Results: Thirty patients were entered into the study. Median survival was nine months (range 1-51 + months). There were eight partial responses (28%, 95% CI: 13%-47%). The median duration of response was 6.5 (range 4-9 months). Grade 3-4 toxicities included neutropenia (grade 3 in eight patients and grade 4 in five), anaemia (grade 3 in one patient) and diarrhoea (grade 3 in two patients). Neutropenia was associated with pyrexia in two patients. Phlebitis at the infusion site occurred in five patients. The treatment was complicated by pulmonary embolism in one patient and deep venous thrombosis in another. Conclusion: HU administered in this schedule is well tolerated. Based on these results and those of other phase II studies, a randomised phase III study of 5-FU, FA and HU versus 5-FU and FA using the standard de Gramont schedule is recommended.

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Objectives: To assess whether cervical mediastinoscopy is necessary before radical resection of malignant pleural mesothelioma (MPM). Methods: Patients who underwent radical excision of MPM in a 48-month period were prospectively followed for evidence of disease recurrence and death. Histological evidence of extra pleural lymph node metastases was correlated with survival. Lymph node size at intraoperative lymphadenectomy was correlated with the presence of metastatic tumour. Results: The 55 patients who underwent radical resection (51 extra pleural pneumonectomies and 4 radical pleurectomies) comprised 50 men and 5 women with a median age of 58 years, range 41-70. Histological examination revealed 50 epithelioid, four biphasic and one sarcomatoid histology. Postoperative IMIG T stage was stage I 4, II 11, III 30 and IV 10. Postoperatively the 17 patients with metastases to the extra pleural lymph nodes had significantly shorter survival (median 4.4 months, 95% CI 3.2-5.4) than those without (median survival 16.3 months, 95% CI 11.6-21.0) P=0.012 Kaplan-Meier analysis. Seventy-seven extra pleural lymph nodes without metastases were measured with a mean long axis diameter of 16.9 mm (range 4-55) ; 22 positive nodes had a mean long axis diameter of 15.2 mm (range 6-30). In 15 of the 17 patients with positive extra pleural nodes, the nodes could have been biopsied at cervical mediastinoscopy. Conclusions: This study confirms that extra pleural nodal metastases are related to poor survival. Pathological nodal involvement cannot be predicted from nodal dimensions. These data suggest that all patients being considered for radical resection of MPM should preferentially undergo preoperative cervical mediastinoscopy irrespective of radiological findings. © 2003 Elsevier B.V. All rights reserved.

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Background Foot ulcers are a leading cause of avoidable hospital admissions and lower extremity amputations. However, large clinical studies describing foot ulcer presentations in the ambulatory setting are limited. The aim of this descriptive observational paper is to report the characteristics of ambulatory foot ulcer patients managed across 13 of 17 Queensland Health & Hospital Services. Methods Data on all foot ulcer patients registered with a Queensland High Risk Foot Form (QHRFF) was collected at their first consult in 2012. Data is automatically extracted from each QHRFF into a Queensland high risk foot database. Descriptive statistics display age, sex, ulcer types and co-morbidities. Statewide clinical indicators of foot ulcer management are also reported. Results Overall, 2,034 people presented with a foot ulcer in 2012. Mean age was 63(±14) years and 67.8% were male. Co-morbidities included 85% had diabetes, 49.7% hypertension, 39.2% dyslipidaemia, 25.6% cardiovascular disease, 13.7% kidney disease and 12.2% smoking. Foot ulcer types included 51.6% neuropathic, 17.8% neuro-ischaemic, 7.2% ischaemic, 6.6% post-surgical and 16.8% other; whilst 31% were infected. Clinical indicator results revealed 98% had their wound categorised, 51% received non-removable offloading, median ulcer healing time was 6-weeks and 37% had ulcer recurrence. Conclusion This paper details the largest foot ulcer database reported in Australia. People presenting with foot ulcers appear predominantly older, male with several co-morbidities. Encouragingly it appears most patients are receiving best practice care. These results may be a factor in the significant reduction of Queensland diabetes foot-related hospitalisations and amputations recently reported.