983 resultados para Cross-flow
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On the basis of serologic cross-reactivity, three immunoglobulin classes homologous to human IgG, IgM and IgA were identified in two species of acquatic mammal representing the orders Cetacea (dolphin) and Pinnipedea (sea lion). Molecular size was estimated by sucrose density gradient ultracentrifugation and Sephadex G-200 chromatography, indicating a 7S IgG, 19S IgM and heterogeneous serum IgA. Human secretory component was readily bound to the IgM of both species and to an apparently lesser extent to the larger molecular size populations of IgA. No binding was observed with IgG. Several antisera specific for human γ-chains gave a single precipitin line with the sea lion IgG but when made to react with dolphin serum produced two lines, suggesting the presence of two different subclasses of IgG in this species.
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ABSTRACT: BACKGROUND: Although smokers tend to have a lower body-mass index than non-smokers, smoking may favour abdominal body fat accumulation. To our knowledge, no population-based studies have assessed the relationship between smoking and body fat composition. We assessed the association between cigarette smoking and waist circumference, body fat, and body-mass index. METHODS: Height, weight, and waist circumference were measured among 6,123 Caucasians (ages 35-75) from a cross-sectional population-based study in Switzerland. Abdominal obesity was defined as waist circumference>=102 cm for men and >=88 cm for women. Body fat (percent total body weight) was measured by electrical bioimpedance. Age- and sex-specific body fat cut-offs were used to define excess body fat. Cigarettes smoked per day were assessed by self-administered questionnaire. Age-adjusted means and odds ratios were calculated using linear and logistic regression. RESULTS: Current smokers (29% of men and 24% of women) had lower mean waist circumference, body fat percentage, and body-mass index compared with non-smokers. Age-adjusted mean waist circumference and body fat increased with cigarettes smoked per day among smokers. The association between cigarettes smoked per day and body-mass index was non-significant. Compared with light smokers, the adjusted odds ratio (OR) for abdominal obesity in men was 1.28 (0.78-2.10) for moderate smokers and 1.94 (1.15-3.27) for heavy smokers (P=0.03 for trend), and 1.07 (0.72-1.58) and 2.15 (1.26-3.64) in female moderate and heavy smokers, respectively (P<0.01 for trend). Compared with light smokers, the OR for excess body fat in men was 1.05 (95% CI: 0.58-1.92) for moderate smokers and 1.15 (0.60-2.20) for heavy smokers (P=0.75 for trend) and 1.34 (0.89-2.00) and 2.11 (1.25-3.57), respectively in women (P=0.07 for trend). CONCLUSION: Among smokers, cigarettes smoked per day were positively associated with central fat accumulation, particularly in women.
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Fluorescence flow cytometry was employed to assess the potential of a vital dye, hydroethiedine, for use in the detection and monitoring of the viability of hemoparasites in infected erythrocytes, using Babesia bovis as a model parasite. The studies demonstrated that hydroethidine is taken up by B. bovis and metabolically converted to the DNA binding fluorochrone, ethidium. Following uptake of the dye, erythrocytes contamine viable parasites were readily distinguished and quantitated. Timed studies with the parasiticidal drug, Ganaseg, showed that it is possible to use the fluorochrome assay to monitor the effects of the drug on the rate of replication and viability of B. bovis in culture. The assay provides a rapid method for evaluation of the in vitro effect of drugs on hemoparasites and for analysis of the effect of various components of the immune response, such as lymphokines, monocyte products, antibodies, and effector cells (T, NK, LAK, ADCC) on the growth and viability of intraerythrocytic parasites.
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Protein extracts obtained from male and female shistosomes were incubated with a gender-specific gene, F-10, transcribed only in adult females and encoding a major egg-shell protein. The protein/DNA interaction was measured using the band shift, DNase-I-footprinting and UV cross-linking techniques. The results showed a clear band shift when a 302 bp restriction fragment containing the 3'end of the gene was incubated with either female or male proteins. This fragment also contained a putative steroid hormone regulatory element (HRE). In contrast, only the male proteins produced a shift with the 495 bp fragment corresponding to the middle region of the gene. DNase I footprinting showed that proteins from males and females interacted with the F-10 gene by binding to multiple adjacent sites along the DNA, thus generatingrelatively long protected fragments of approximately 100 bp. This result suggested that the adjacent binding of several moles of proteins occured at the 5'end of the gene. UV cross-linking between schistosome proteins and a 21 bp synthetic oligonucleotide the F-10 HRE, evidence proteins having MWS of 30,45 and 65 kDNA. These proteins are presumably involved in the regulation of transcription of the F-10 gene.
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BACKGROUND: According to recent guidelines, patients with coronary artery disease (CAD) should undergo revascularization if significant myocardial ischemia is present. Both, cardiovascular magnetic resonance (CMR) and fractional flow reserve (FFR) allow for a reliable ischemia assessment and in combination with anatomical information provided by invasive coronary angiography (CXA), such a work-up sets the basis for a decision to revascularize or not. The cost-effectiveness ratio of these two strategies is compared. METHODS: Strategy 1) CMR to assess ischemia followed by CXA in ischemia-positive patients (CMR + CXA), Strategy 2) CXA followed by FFR in angiographically positive stenoses (CXA + FFR). The costs, evaluated from the third party payer perspective in Switzerland, Germany, the United Kingdom (UK), and the United States (US), included public prices of the different outpatient procedures and costs induced by procedural complications and by diagnostic errors. The effectiveness criterion was the correct identification of hemodynamically significant coronary lesion(s) (= significant CAD) complemented by full anatomical information. Test performances were derived from the published literature. Cost-effectiveness ratios for both strategies were compared for hypothetical cohorts with different pretest likelihood of significant CAD. RESULTS: CMR + CXA and CXA + FFR were equally cost-effective at a pretest likelihood of CAD of 62% in Switzerland, 65% in Germany, 83% in the UK, and 82% in the US with costs of CHF 5'794, euro 1'517, £ 2'680, and $ 2'179 per patient correctly diagnosed. Below these thresholds, CMR + CXA showed lower costs per patient correctly diagnosed than CXA + FFR. CONCLUSIONS: The CMR + CXA strategy is more cost-effective than CXA + FFR below a CAD prevalence of 62%, 65%, 83%, and 82% for the Swiss, the German, the UK, and the US health care systems, respectively. These findings may help to optimize resource utilization in the diagnosis of CAD.
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Cross-sectional and evolutive studies on schistosomiasis mansoni were carried out before and after mass treatment in the endemic areas of Capitao Andrade and Padre Paraíso, state of Minas Gerais, Riachuelo, state of Sergipe, Alhandra, state of Paraíba, and Aliança, Alegre and Coroatá, lowland of the state of Maranhao, Brazil, in the last eighteen years. The studies included clinical and fecal examination by the Kato-Katz quantitative technique, skin testfor Schistosoma mansoni infection, evaluation of man-water contact and other epidemiological investigations such as infection rate and dynamic of the snail population. Results showed: (1) Higher prevalence of S. mansoni infection, greater egg load elimination and higher and earlier morbidity of the chronic froms of the disease in the southeast areas of Capitao Andrade and Padre Paraíso; (2) The incidence of hepatosplenic form is higher in some family clusters, in whites and mullattos in all the endemic areas but develop earlier in the southeast; (3) The prevalence and morbidity of schistosomiasis are decreasing both in the mass treated northeast and in the untreated southeast areas; (4) The mass treatment reduces rapidily the prevalence of the infection and the morbidity of the disease but can not control it because of the frequent reinfections due to the intensity of man-water contact.
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The endothelin receptor antagonist avosentan may cause fluid overload at doses of 25 and 50 mg, but the actual mechanisms of this effect are unclear. We conducted a placebo-controlled study in 23 healthy subjects to assess the renal effects of avosentan and the dose dependency of these effects. Oral avosentan was administered once daily for 8 days at doses of 0.5, 1.5, 5, and 50 mg. The drug induced a dose-dependent median increase in body weight, most pronounced at 50 mg (0.8 kg on day 8). Avosentan did not affect renal hemodynamics or plasma electrolytes. A dose-dependent median reduction in the fractional renal excretion of sodium was found (up to 8.7% at avosentan 50 mg); this reduction was paralleled by a dose-related increase in proximal sodium reabsorption. It is suggested that avosentan dose-dependently induces sodium retention by the kidney, mainly through proximal tubular effects. The potential clinical benefits of avosentan should therefore be investigated at doses of <or= 5 mg.
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BACKGROUND: As the diversity of the European population evolves, measuring providers' skillfulness in cross-cultural care and understanding what contextual factors may influence this is increasingly necessary. Given limited information about differences in cultural competency by provider role, we compared cross-cultural skillfulness between physicians and nurses working at a Swiss university hospital. METHODS: A survey on cross-cultural care was mailed in November 2010 to front-line providers in Lausanne, Switzerland. This questionnaire included some questions from the previously validated Cross-Cultural Care Survey. We compared physicians' and nurses' mean composite scores and proportion of "3-good/4-very good" responses, for nine perceived skillfulness items (4-point Likert-scale) using the validated tool. We used linear regression to examine how provider role (physician vs. nurse) was associated with composite skillfulness scores, adjusting for demographics (gender, non-French dominant language), workplace (time at institution, work-unit "sensitized" to cultural-care), reported cultural-competence training, and cross-cultural care problem-awareness. RESULTS: Of 885 questionnaires, 368 (41.2%) returned the survey: 124 (33.6%) physicians and 244 (66.4%) nurses, reflecting institutional distribution of providers. Physicians had better mean composite scores for perceived skillfulness than nurses (2.7 vs. 2.5, p < 0.005), and significantly higher proportion of "good/very good" responses for 4/9 items. After adjusting for explanatory variables, physicians remained more likely to have higher skillfulness (β = 0.13, p = 0.05). Among all, higher skillfulness was associated with perception/awareness of problems in the following areas: inadequate cross-cultural training (β = 0.14, p = 0.01) and lack of practical experience caring for diverse populations (β = 0.11, p = 0.04). In stratified analyses among physicians alone, having French as a dominant language (β = -0.34, p < 0.005) was negatively correlated with skillfulness. CONCLUSIONS: Overall, there is much room for cultural competency improvement among providers. These results support the need for cross-cultural skills training with an inter-professional focus on nurses, education that attunes provider awareness to the local issues in cross-cultural care, and increased diversity efforts in the work force, particularly among physicians.
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Treaty Establishing the European Community, operative until December 1st 2009, had already established in its article 2 the mission of the up until then European Community and actual European Union is to promote an harmonious, equilibrated and sustainable development of the economic activities of the whole Community. This Mission must be achieved by establishing a Common Market, an Economic and Monetary Union and the realization of Common Policies. One of the instruments to obtain these objectives is the use of free circulation of people, services and capitals inside the Common and Interior Market of the European Union. The European Union is characterized by the confirmation of the total movement of capitals, services and individuals and legal peoples’ freedom; freedom that was already predicated by the Maastricht Treaty, through the suppression of whatever obstacles which are in the way of the objectives before exposed. The old TEC in its Title III, now Title IV of the Treaty on the Functioning of the European Union, covered the free circulation of people, services and capitals. Consequently, the inclusion of this mechanism inside one of the regulating texts of the European Union indicates the importance this freedom supposes for the European Union objectives’ development. Once stood up the relevance of the free movement of people, services and capitals, we must mention that in this paper we are going to centre our study in one of these freedoms of movement: the free movement of capital. In order to analyze in detail the free movement of capital within the European framework, we are going to depart from the analysis of the existent case law of the Court of Justice of the European Union. The use of jurisprudence is basic to know how Community legislation is interpreted. For this reason, we are going to develop this work through judgements dictated by the European Union Court. This way we can observe how Member States’ regulating laws and the European Common Law affect the free movement of capital. The starting point of this paper will be the Judgement C-67/08 European Court of Justice of February 12th 2009, known as Block case. So, following the argumentation the Luxemburg Court did about the mentioned case, we are going to develop how free movement of capital could be affected by the current disparity of Member States’ legislation. This disparity can produce double taxation cases due to the lack of tax harmonized legislation within the interior market and the lack of treaties to avoid double taxation within the European Union. Developing this idea we are going to see how double taxation, at least indirectly, can infringe free movement of capital.
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The present study was undertaken to examine the cross-sectional vascular compliance at the anastomotic site. METHODS AND MATERIAL: We performed end-to-end anastomosis on the carotid artery of six pigs using continuous 6/0 polypropylene. Four carotid arteries were excised and mounted in a perfusion chamber while the remaining two were left in living animals. We used pulsed ultrasound (NIUS 02) to generate detailed longitudinal profiles of diameter and compliance in the proximity and on the anastomosis. RESULTS: On the anastomosis, the vessel diameter decreases (-1 to -2.6% of diastolic diameter) when blood pressure increases with an exponential correlation (R2 = 0.75). The arterial compliance at the anastomosis was negative: the vessel cross-section reduction for a pulse pressure of 1 up to 32 mmHg was 0.9 to 2% of diastolic vessel cross-section. CONCLUSIONS: Vessel movement generated a dynamic stenosis whose magnitude seems to depend on blood pressure level. Increasing blood pressure causes the retraction of vessel ends which causes vessel lumen reduction. These results suggest that continuous suture does not provide the continuity of mechanical properties of the artery.
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Despite the long tradition for asking about the negative social and health consequences of alcohol consumption in surveys, little is known about the dimensionality of these consequences. Analysing cross-sectional and longitudinal data from the Nordic Taxation Study collected for Sweden, Finland, and Denmark in two waves in 2003 and 2004 by means of an explorative principal component analysis for categorical data (CATPCA), it is tested whether consequences have a single underlying dimension across cultures. It further tests the reliability, replicability, concurrent and predictive validity of the consequence scales. A one-dimensional solution was commonly preferable. Whereas the two-dimensional solution was unable to distinguish clearly between different concepts of consequences, the one-dimensional solution resulted in interpretable, generally very stable scales within countries across different samples and time.
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BACKGROUND: The debate about a possible relationship between aerobic fitness and motor skills with cognitive development in children has recently re-emerged, because of the decrease in children's aerobic fitness and the concomitant pressure of schools to enhance cognitive performance. As the literature in young children is scarce, we examined the cross-sectional and longitudinal relationship of aerobic fitness and motor skills with spatial working memory and attention in preschool children. METHODS: Data from 245 ethnically diverse preschool children (mean age: 5.2 (0.6) years, girls: 49.4%) analyzed at baseline and 9 months later. Assessments included aerobic fitness (20 m shuttle run) and motor skills with agility (obstacle course) and dynamic balance (balance beam). Cognitive parameters included spatial working memory (IDS) and attention (KHV-VK). All analyses were adjusted for age, sex, BMI, migration status, parental education, native language and linguistic region. Longitudinal analyses were additionally adjusted for the respective baseline value. RESULTS: In the cross-sectional analysis, aerobic fitness was associated with better attention (r=0.16, p=0.03). A shorter time in the agility test was independently associated with a better performance both in working memory (r=-0.17, p=0.01) and in attention (r=-0.20, p=0.01). In the longitudinal analyses, baseline aerobic fitness was independently related to improvements in attention (r=0.16, p=0.03), while baseline dynamic balance was associated with improvements in working memory (r=0.15, p=0.04). CONCLUSIONS: In young children, higher baseline aerobic fitness and motor skills were related to a better spatial working memory and/or attention at baseline, and to some extent also to their future improvements over the following 9 months. TRIAL REGISTRATION: clinicaltrials.gov NCT00674544.