939 resultados para Repeated DNAs
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RATIONALE AND OBJECTIVES: Dose reduction may compromise patients because of a decrease of image quality. Therefore, the amount of dose savings in new dose-reduction techniques needs to be thoroughly assessed. To avoid repeated studies in one patient, chest computed tomography (CT) scans with different dose levels were performed in corpses comparing model-based iterative reconstruction (MBIR) as a tool to enhance image quality with current standard full-dose imaging. MATERIALS AND METHODS: Twenty-five human cadavers were scanned (CT HD750) after contrast medium injection at different, decreasing dose levels D0-D5 and respectively reconstructed with MBIR. The data at full-dose level, D0, have been additionally reconstructed with standard adaptive statistical iterative reconstruction (ASIR), which represented the full-dose baseline reference (FDBR). Two radiologists independently compared image quality (IQ) in 3-mm multiplanar reformations for soft-tissue evaluation of D0-D5 to FDBR (-2, diagnostically inferior; -1, inferior; 0, equal; +1, superior; and +2, diagnostically superior). For statistical analysis, the intraclass correlation coefficient (ICC) and the Wilcoxon test were used. RESULTS: Mean CT dose index values (mGy) were as follows: D0/FDBR = 10.1 ± 1.7, D1 = 6.2 ± 2.8, D2 = 5.7 ± 2.7, D3 = 3.5 ± 1.9, D4 = 1.8 ± 1.0, and D5 = 0.9 ± 0.5. Mean IQ ratings were as follows: D0 = +1.8 ± 0.2, D1 = +1.5 ± 0.3, D2 = +1.1 ± 0.3, D3 = +0.7 ± 0.5, D4 = +0.1 ± 0.5, and D5 = -1.2 ± 0.5. All values demonstrated a significant difference to baseline (P < .05), except mean IQ for D4 (P = .61). ICC was 0.91. CONCLUSIONS: Compared to ASIR, MBIR allowed for a significant dose reduction of 82% without impairment of IQ. This resulted in a calculated mean effective dose below 1 mSv.
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As Schistosoma sp. control programs are chiefly based on treatment of infected population, adequate case finding has a crucial role. The available diagnostic methods are far from ideal, since the search for eggs in stools and the detection of circulating antigens lack sensitivity in low prevalence and post-treatment situations and antibody detection lacks specificity. In most endemic foci, repeated treatment of infected people leaves a number of non-diagnosed and consequently non-treated persons, enough to maintain a persistent residue of 5 to 10% prevalence. In an attempt to surpass these diagnostic limitations we have developed a polymerase chain reaction (PCR) for the detection of Schistosoma sp. in feces that, in a first population study, has shown to be more sensitive than three-repeated stool Kato-Katz examination. The PCR may constitute a valuable tool for the diagnosis of the Schistosoma sp. infection in special situations, when high sensitivity and specificity are required and infrastructure is available.
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Ethanolic crude extracts from the roots of Chaptalia nutans, traditionally used in Brazilian folk medicine, were screened against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa by using the disk diffusion test technique. S. aureus with 14 mm inhibition zone was considered susceptible. E. coli and P. aeruginosa without such a zone were considered resistant. As a result of this finding, the ethanolic crude extract was fractionated on silica gel column chromatography into five fractions. The ethyl acetate fraction was active against S. aureus and Bacillus subtilis. Further column chromatography separation of the ethyl acetate fraction afforded 30 fractions, which were assayed against S. aureus. Fractions 16 and 17 showed inhibition zones with S. aureus, indicating the presence of active compounds, and were subjected to purification by repeated preparative thin layer chromatography. The pure compound 7-O-beta-D-glucopyranosyl-nutanocoumarin inhibited B. subtilis and S. aureus at concentrations of 62.5 µg/ml and 125 µg/ml, respectively. The antibacterial property of C. nutans appears to have justified its use for the treatment of wounds, which are contaminated through bacterial infections.
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OBJECTIVE: To determine the psychometric properties of an adapted version of the Falls Efficacy Scale (FES) in older rehabilitation patients. DESIGN: Cross-sectional survey. SETTING: Postacute rehabilitation facility in Switzerland. PARTICIPANTS: Seventy elderly persons aged 65 years and older receiving postacute, inpatient rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: FES questions asked about subject's confidence (range, 0 [none]-10 [full]) in performing 12 activities of daily living (ADLs) without falling. Construct validity was assessed using correlation with measures of physical (basic ADLs [BADLs]), cognitive (Mini-Mental State Examination [MMSE]), affective (15-item Geriatric Depression Scale [GDS]), and mobility (Performance Oriented Mobility Assessment [POMA]) performance. Predictive validity was assessed using the length of rehabilitation stay as the outcome. To determine test-retest reliability, FES administration was repeated in a random subsample (n=20) within 72 hours. RESULTS: FES scores ranged from 10 to 120 (mean, 88.7+/-26.5). Internal consistency was optimal (Cronbach alpha=.90), and item-to-total correlations were all significant, ranging from .56 (toilet use) to .82 (reaching into closets). Test-retest reliability was high (intraclass correlation coefficient, .97; 95% confidence interval, .95-.99; P<.001). Subjects reporting a fall in the previous year had lower FES scores than nonfallers (85.0+/-25.2 vs 94.4+/-27.9, P=.054). The FES correlated with POMA (Spearman rho=.40, P<.001), MMSE (rho=.37, P=.001), BADL (rho=.43, P<.001), and GDS (rho=-.53, P<.001) scores. These relationships remained significant in multivariable analysis for BADLs and GDS, confirming FES construct validity. There was a significant inverse relationship between FES score and the length of rehabilitation stay, independent of sociodemographic, functional, cognitive, and fall status. CONCLUSIONS: This adapted FES is reliable and valid in older patients undergoing postacute rehabilitation. The independent association between poor falls efficacy and increased length of stay has not been previously described and needs further investigations.
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The systematic collection of behavioural information is an important component of second-generation HIV surveillance. The extent of behavioural surveillance among injecting drug users (IDUs) in Europe was examined using data collected through a questionnaire sent to all 31 countries of the European Union and European Free Trade Association as part of a European-wide behavioural surveillance mapping study on HIV and other sexually transmitted infections. The questionnaire was returned by 28 countries during August to September 2008: 16 reported behavioural surveillance studies (two provided no further details). A total of 12 countries used repeated surveys for behavioural surveillance and five used their Treatment Demand Indicator system (three used both approaches). The data collected focused on drug use, injecting practices, testing for HIV and hepatitis C virus and access to healthcare. Eight countries had set national indicators: three indicators were each reported by five countries: the sharing any injecting equipment, uptake of HIV testing and uptake of hepatitis C virus testing. The recall periods used varied. Seven countries reported conducting one-off behavioural surveys (in one country without a repeated survey, these resulted an informal surveillance structure). All countries used convenience sampling, with service-based recruitment being the most common approach. Four countries had used respondent-driven sampling. Three fifths of the countries responding (18/28) reported behavioural surveillance activities among IDUs; however, harmonisation of behavioural surveillance indicators is needed.
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This article examines the existence of a habituation effect to unemployment: Does the subjective well-being of unemployed people decline less if unemployment is more widespread? The underlying idea is that unemployment hysteresis may operate through a sociological channel: if many people in the community lose their job and remain unemployed over an extended period, the psychological cost of being unemployed diminishes and the pressure to accept a new job declines. We analyze this question with individual-level data from the German Socio-Economic Panel (1984-2010) and the Swiss Household Panel (2000-2010). Our fixed-effects estimates show no evidence for a mitigating effect of high surrounding unemployment on the subjective well-being of the unemployed. Becoming unemployed hurts as much when regional unemployment is high as when it is low. Likewise, the strongly harmful impact of being unemployed on well-being does not wear off over time, nor do repeated episodes of unemployment make it any better. It thus appears doubtful that an unemployment shock becomes persistent because the unemployed become used to, and hence reasonably content with, being without a job.
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Laurencetown, Lenaderg & Tullylish Community Association (LLT) manage a community centre which serves the surrounding rural areas. Programmes include: parent & toddler, youth group, older peopleï¿_s group (offering 1-1 support) and supports other outlying rural groups. LLT has completed 3 Level 2 projects in the past.The first 3 projects have helped develop better understanding and promoted better access to pharmacy services etc (3 miles away), have raised the profile of LLT and put health on the agenda and has worked well with a range of specific groups including men, older people, pre schoolers etc and is currently seeking to target teenagers and parents. A good working relationship has developed between the pharmacist and LLT. They want to continue a similar approach developed through their Level 2 applications but with an increased focus on pre-school children and young people (teenagers) with their parents. Year 1 includes a health fair, 6 talks to local groups, 10 consultations for older people, 4 sessions for mothers, 4 sessions for fathers and 3 sessions with young people. Most of these, apart from the Health Fair, will be repeated in Year 2 & 3.
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L'utilisation de l'Internet comme medium pour faire ses courses et achats a vu une croissance exponentielle. Cependant, 99% des nouveaux business en ligne échouent. La plupart des acheteurs en ligne ne reviennent pas pour un ré-achat et 60% abandonnent leur chariot avant de conclure l'achat. En effet, après le premier achat, la rétention du consommateur en ligne devient critique au succès du vendeur de commerce électronique. Retenir des consommateurs peut sauver des coûts, accroître les profits, et permet de gagner un avantage compétitif.Les recherches précédentes ont identifié la loyauté comme étant le facteur le plus important dans la rétention du consommateur, et l'engagement ("commitment") comme étant un des facteurs les plus importants en marketing relationnel, offrant une réflexion sur la loyauté. Pourtant, nous n'avons pu trouver d'étude en commerce électronique examinant l'impact de la loyauté en ligne et de l'engagement en ligne ("online commitment") sur le ré-achat en ligne. Un des avantages de l'achat en ligne c'est la capacité à chercher le meilleur prix avec un clic. Pourtant, nous n'avons pu trouver de recherche empirique en commerce électronique qui examinait l'impact de la perception post-achat du prix sur le ré-achat en ligne.L'objectif de cette recherche est de développer un modèle théorique visant à comprendre le ré-achat en ligne, ou la continuité d'achat ("purchase continuance") du même magasin en ligne.Notre modèle de recherche a été testé dans un contexte de commerce électronique réel, sur un échantillon total de 1,866 vrais acheteurs d'un même magasin en ligne. L'étude est centrée sur le ré-achat. Par conséquent, les répondants sélectionnés aléatoirement devaient avoir acheté au moins une fois de ce magasin en ligne avant le début de l'enquête. Cinq mois plus tard, nous avons suivi les répondants pour voir s'ils étaient effectivement revenus pour un ré-achat.Notre analyse démontre que l'intention de ré-achat en ligne n'a pas d'impact significatif sur le ré-achat en ligne. La perception post-achat du prix en ligne ("post-purchase Price perception") et l'engagement normatif en ligne ("Normative Commitment") n'ont pas d'impact significatif sur l'intention de ré-achat en ligne. L'engagement affectif en ligne ("Affective Commitment"), l'attitude loyale en ligne ("Attitudinal Loyalty"), le comportement loyal en ligne ("Behavioral Loyalty"), l'engagement calculé en ligne ("Calculative Commitment") ont un impact positif sur l'intention de ré-achat en ligne. De plus, l'attitude loyale en ligne a un effet de médiation partielle entre l'engagement affectif en ligne et l'intention de ré-achat en ligne. Le comportement loyal en ligne a un effet de mediation partielle entre l'attitude loyale en ligne et l'intention de ré-achat en ligne.Nous avons réalisé deux analyses complémentaires : 1) Sur un échantillon de premiers acheteurs, nous trouvons que la perception post-achat du prix en ligne a un impact positif sur l'intention de ré-achat en ligne. 2) Nous avons divisé l'échantillon de l'étude principale entre des acheteurs répétitifs Suisse-Romands et Suisse-Allemands. Les résultats démontrent que les Suisse-Romands montrent plus d'émotions durant l'achat en ligne que les Suisse-Allemands. Nos résultats contribuent à la recherche académique mais aussi aux praticiens de l'industrie e-commerce.AbstractThe use of the Internet as a shopping and purchasing medium has seen exceptional growth. However, 99% of new online businesses fail. Most online buyers do not comeback for a repurchase, and 60% abandon their shopping cart before checkout. Indeed, after the first purchase, online consumer retention becomes critical to the success of the e-commerce vendor. Retaining existing customers can save costs, increase profits, and is a means of gaining competitive advantage.Past research identified loyalty as the most important factor in achieving customer retention, and commitment as one of the most important factors in relationship marketing, providing a good description of what type of thinking leads to loyalty. Yet, we could not find an e-commerce study investing the impact of both online loyalty and online commitment on online repurchase. One of the advantages of online shopping is the ability of browsing for the best price with one click. Yet, we could not find an e- commerce empirical research investigating the impact of post-purchase price perception on online repurchase.The objective of this research is to develop a theoretical model aimed at understanding online repurchase, or purchase continuance from the same online store.Our model was tested in a real e-commerce context with an overall sample of 1, 866 real online buyers from the same online store.The study focuses on repurchase. Therefore, randomly selected respondents had purchased from the online store at least once prior to the survey. Five months later, we tracked respondents to see if they actually came back for a repurchase.Our findings show that online Intention to repurchase has a non-significant impact on online Repurchase. Online post-purchase Price perception and online Normative Commitment have a non-significant impact on online Intention to repurchase, whereas online Affective Commitment, online Attitudinal Loyalty, online Behavioral Loyalty, and online Calculative Commitment have a positive impact on online Intention to repurchase. Furthermore, online Attitudinal Loyalty partially mediates between online Affective Commitment and online Intention to repurchase, and online Behavioral Loyalty partially mediates between online Attitudinal Loyalty and online Intention to repurchase.We conducted two follow up analyses: 1) On a sample of first time buyers, we find that online post-purchase Price perception has a positive impact on Intention. 2) We divided the main study's sample into Swiss-French and Swiss-German repeated buyers. Results show that Swiss-French show more emotions when shopping online than Swiss- Germans. Our findings contribute to academic research but also to practice.
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The use of liposomes as carriers for the delivery of biologically active molecules into the eye is of major interest. Indeed, encapsulation of biologically active molecules in liposomes may increase their bioavailability and may induce a sustained release, thus avoiding repeated intraocular injections and reducing side effects. We describe here the fate of rhodamine-conjugated liposomes (Rh-Lip) injected into the vitreous of normal Lewis rats. Twenty-four hours after intravitreal injection fluorescent liposomes were detected in the vitreous, the inner layer of the retina and to a lesser extent in the anterior segment of the eye. In addition, numerous Rh-Lip were also observed in the episclera and conjunctival stroma, in conjunctival lymphatic vessels and cervical lymph nodes (LN) draining the conjunctiva and the eye. In the LN, Rh-Lip were taken up by resident macrophages adjacent to CD4+ and CD8+ T cells. Thus, intravitreal injection of anti-inflammatory drugs loaded in liposomes could modulate the ocular immune microenvironment. In addition the passage of drugs into the cervical LN could alter the immune status of these LN and contribute to the regulation of intraocular inflammation. Our results suggest that this phenomenon should be taken into account to design new therapies based on intraocular drug administration.
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BACKGROUND AND AIMS: little is known regarding the reproducibility of body fat measuring devices; hence, we assessed the between and within-device reproducibility, and the within-day variability of body fat measurements. METHODS: body fat percentage was measured twice on seventeen female students aged between 18 and 20 with a body mass index of 21.9 ± 2.5 kg/m2 (mean ± SD) using seven bipolar bioelectrical impedance devices. Each participant was also measured each hour between 7:00 and 22:00. RESULTS: the correlation between first and second measurements was very high (Spearman r between 0.985 and 1.000, p<0.001), as well as between devices (Spearman r between 0.916 and 0.991, p<0.001). Repeated measurements analysis showed no differences were between devices (p=0.59) or readings (first vs. second: p=0.74). Conversely, significant differences were found between assessment periods throughout the day, measurements made in the morning being lower than those made in the afternoon (F test for repeated values= 6.58, p<0.001). CONCLUSIONS: the between and within-device reproducibility for measuring body fat is high, enabling the use of multiple devices in a single study. Conversely, small but significant changes in body fat measurements occur during the day, urging body fat measurements to be performed at fixed times.
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Objective. Vibration training (VT) is a new exercise method, with good acceptance among sedentary subjects, due to its passive principle: the machine moves the subject, not the opposite. We hypothesize that untrained subjects can benefit from a greater cardiovascular and metabolic stimulation than trained athletes, resembling classical aerobic-type activity, in addition of eliciting strength gains shown in diverse studies. Methods. 3 group of male subjects, inactive (SED), endurance trained athletes (END) and strength trained athletes (STR) underwent fitness (VO2max) and lower-body strength tests (isokinetic). Subjects were submitted to a session of oscillating VT, composed of 3 exercises (isometric half-squat, dynamic squat, dynamic squat with added load), each of 3 minutes duration, and repeated at 3 frequencies. VO2, heart rate and Borg scale were monitored. Results. 27 healthy subjects (10 SED, 9 END and 8 STR), mean age 24.5 (SED), 25.0 (STR) and 29.8 (END) were included. VO2max was significantly different as expected (47.9 vs. 52.9 vs. 63.9 ml/kg/min, resp. for SED, STR and END). Isokinetic dominant leg extensors strength was higher in STR (3.32 Nm/kg vs. 2.60 and 2.74 in SED and END). During VT, peak oxygen consumption (% of VO2max) attained was 59.3 in SED, 50.8 in STR and 48.0 in END (P<0.001 between SED and other subjects). Peak heart rate (% of heart rate max) was 82.7 in SED, 80.4 in STR and 72.4 in END. In SED, dynamic exercises without extra load elicited 51.0% of VO2max and 72.1% of heart rate max, and perceived effort reached 15.1/20. Conclusions. VT is an unconventional type of exercise, which has been shown to enhance strength, bone density, balance and flexibility. Users are attracted by the relative passivity. In SED, we show that VT elicits sufficient cardiovascular response to benefit overall fitness in addition to the known strength effects. VT's higher acceptance as an exercise in sedentary people, compared to jogging or cycling for example, can lead to better adherence to physical activity. Although long-term effects of VT on health are not avalaible, we believe this type of combination of aerobic and resistance-type exercise can be beneficial on multiple health parameters, especially cardiovascular health.
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Whereas during the last few years handling of the transcutaneous PO2 (tcPO2) and PCO2 (tcPCO2) sensor has been simplified, the high electrode temperature and the short application time remain major drawbacks. In order to determine whether the application of a topical metabolic inhibitor allows reliable measurement at a sensor temperature of 42 degrees C for a period of up to 12 h, we performed a prospective, open, nonrandomized study in a sequential sample of 20 critically ill neonates. A total of 120 comparisons (six repeated measurements per patient) between arterial and transcutaneous values were obtained. Transcutaneous values were measured with a control sensor at 44 degrees C (conventional contact medium, average application time 3 h) and a test sensor at 42 degrees C (Eugenol solution, average application time 8 h). Comparison of tcPO2 and PaO2 at 42 degrees C (Eugenol solution) showed a mean difference of +0.16 kPa (range +1.60 to -2.00 kPa), limits of agreement +1.88 and -1.56 kPa. Comparison of tcPO2 and PaO2 at 44 degrees C (control sensor) revealed a mean difference of +0.02 kPa (range +2.60 to -1.90 kPa), limits of agreement +2.12 and -2.08 kPa. Comparison of tcPCO2 and PaCO2 at 42 degrees C (Eugenol solution) showed a mean difference of +0.91 (range +2.30 to +0.10 kPa), limits of agreement +2.24 and -0.42 kPa. Comparison of tcPCO2 and PaCO2 at 44 degrees C (control sensor) revealed a mean difference of +0.63 kPa (range 1.50 to -0.30 kPa), limits of agreement +1.73 and -0.47 kPa. CONCLUSION: Our results show that the use of an Eugenol solution allows reliable measurement of tcPO2 at a heating temperature of 42 degrees C; the application time can be prolongued up to a maximum of 12 h without aggravating the skin lesions. The performance of the tcPCO2 monitor was slightly worse at 42 degrees C than at 44 degrees C suggesting that for the Eugenol solution the metabolic offset should be corrected.
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Random amplified polymorphic DNA analysis was applied to DNAs extracted from Trichuris trichiura eggs recovered from human fecal samples. Four out of 6 primers tested displayed 18 distinct and well defined polymorphic patterns, ranging from 650 to 3200 base pairs. These results, upon retrieval and DNA sequencing of some of these bands from agarose gels, might help in establishing T. trichiura specific genetic markers, not available yet, and an important step to design primers to be used in molecular diagnosis approaches.
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Uveal melanoma metastases occur most commonly in the liver. Given the 50% mortality rate in patients at high risk of developing liver metastases, we tested an adjuvant intra-arterial hepatic (i.a.h.) chemotherapy with fotemustine after proton beam irradiation of the primary tumour. We treated 22 high-risk patients with adjuvant i.a.h. fotemustine. Planned treatment duration was 6 months, starting with four weekly doses of 100 mg/m(2), and after a 5-week rest, repeated every 3 weeks. The survival of this patient group was compared with that of a 3 : 1 matched control group randomly selected from our institutional database. Half of the patients experienced > or =grade 3 hepatotoxicity (one patient developing cholangitis 8 years later). Catheter-related complications occurred in 18%. With a median follow-up of 4.6 years for the fotemustine group and 8.5 years for the control group, median overall survival was 9 years [95% confidence interval (CI) 2.2-12.7] and 7.4 years (95% CI 5.4-12.7; P=0.5), respectively, with 5-year survival rates of 75 and 56%. Treatment with adjuvant i.a.h. fotemustine is feasible. However, toxicities are important. Although our data suggest a survival benefit, it was not statistically significant. Confirming such a benefit would require a large, internationally coordinated, prospective randomized trial.
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In occupational exposure assessment of airborne contaminants, exposure levels can either be estimated through repeated measurements of the pollutant concentration in air, expert judgment or through exposure models that use information on the conditions of exposure as input. In this report, we propose an empirical hierarchical Bayesian model to unify these approaches. Prior to any measurement, the hygienist conducts an assessment to generate prior distributions of exposure determinants. Monte-Carlo samples from these distributions feed two level-2 models: a physical, two-compartment model, and a non-parametric, neural network model trained with existing exposure data. The outputs of these two models are weighted according to the expert's assessment of their relevance to yield predictive distributions of the long-term geometric mean and geometric standard deviation of the worker's exposure profile (level-1 model). Bayesian inferences are then drawn iteratively from subsequent measurements of worker exposure. Any traditional decision strategy based on a comparison with occupational exposure limits (e.g. mean exposure, exceedance strategies) can then be applied. Data on 82 workers exposed to 18 contaminants in 14 companies were used to validate the model with cross-validation techniques. A user-friendly program running the model is available upon request.