91 resultados para Approaches to Nanotechnology and Nanoscience
Resumo:
Background: Most migrant studies have compared health characteristics between migrants and nationals of the host country. We aimed at comparing health characteristics of migrants with nationals from their home country. Methods: Portuguese national health survey (2005-6; 30,173 participants aged 18-75 years) and four national health surveys conducted in Switzerland (2002, 2004, 2007 and 2011, totalling 1,170 Portuguese migrants of the same age range). Self-reported data on length of stay, cardiovascular risk factors, healthcare use and health status were collected. Results: Resident Portuguese were significantly older and more educated than migrants. Resident Portuguese had a higher mean BMI and prevalence of obesity than migrants. Resident Portuguese also reported more frequently being hypertensive and having their blood pressure screened within the last year. On the contrary, migrant Portuguese were more frequently smokers, had a medical visit in the previous year more frequently and self-rated their health higher than resident Portuguese. After adjustment for age, gender, marital status and education, migrants had a higher likelihood smoking, of having a medical visit the previous year, and of self-rating their current health as good or very good than resident Portuguese. Compared to Portuguese residents, cholesterol screening in the previous year was more common only among migrants living in Switzerland for more than 17 years. Conclusion: Portuguese migrants in Switzerland do not differ substantially from resident Portuguese regarding most cardiovascular risk factors. Migrants appear to benefit from higher healthcare accessibility and consider themselves healthier than Portuguese residents.
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Small supernumerary marker chromosomes (sSMCs) are structurally abnormal chromosomes that cannot be characterized by karyotype. In many prenatal cases of de novo sSMC, the outcome of pregnancy is difficult to predict because the euchromatin content is unclear. This study aimed to determine the presence or absence of euchromatin material of 39 de novo prenatally ascertained sSMC by array-comparative genomic hybridization (array-CGH) or single nucleotide polymorphism (SNP) array. Cases were prospectively ascertained from the study of 65,000 prenatal samples [0.060%; 95% confidence interval (CI), 0.042-0.082]. Array-CGH showed that 22 markers were derived from non-acrocentric markers (56.4%) and 7 from acrocentic markers (18%). The 10 additional cases remained unidentified (25.6%), but 7 of 10 could be further identified using fluorescence in situ hybridization; 69% of de novo sSMC contained euchromatin material, 95.4% of which for non-acrocentric markers. Some sSMC containing euchromatin had a normal phenotype (31% for non-acrocentric and 75% for acrocentric markers). Statistical differences between normal and abnormal phenotypes were shown for the size of the euchromatin material (more or less than 1 Mb, p = 0.0006) and number of genes (more or less than 10, p = 0.0009). This study is the largest to date and shows the utility of array-CGH or SNP array in the detection and characterization of de novo sSMC in a prenatal context.
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Via a transcription factor, Foxp3, immunoregulatory CD4(+)CD25(+) T cells (T reg cells) play an important role in suppressing the function of other T cells. Adoptively transferring high numbers of T reg cells can reduce the intensity of the immune response, thereby providing an attractive prospect for inducing tolerance. Extending our previous findings, we describe an in vivo approach for inducing rapid expansion of T reg cells by injecting mice with interleukin (IL)-2 mixed with a particular IL-2 monoclonal antibody (mAb). Injection of these IL-2-IL-2 mAb complexes for a short period of 3 d induces a marked (>10-fold) increase in T reg cell numbers in many organs, including the liver and gut as well as the spleen and lymph nodes, and a modest increase in the thymus. The expanded T reg cells survive for 1-2 wk and are highly activated and display superior suppressive function. Pretreating with the IL-2-IL-2 mAb complexes renders the mice resistant to induction of experimental autoimmune encephalomyelitis; combined with rapamycin, the complexes can also be used to treat ongoing disease. In addition, pretreating mice with the complexes induces tolerance to fully major histocompatibility complex-incompatible pancreatic islets in the absence of immunosuppression. Tolerance is robust and the majority of grafts are accepted indefinitely. The approach described for T reg cell expansion has clinical potential for treating autoimmune disease and promoting organ transplantation.
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OBJECTIVES: To define properly the consequences of oxygen deprivation and readmission for the functioning of the developing heart. METHODS: Spontaneously beating hearts excised from three-day-old chick embryos were loaded with a drop of viscous nontoxic silicone oil and cultured in a special chamber in which variations of PO2 at the tissue level could be strictly controlled. All parts of the hearts were simultaneously submitted to identical changes in PO2. Instantaneous heart rate, myocardial shortening, velocities of contraction and relaxation, and mechanical propagation along the heart tube were determined photometrically. RESULTS: The hearts, submitted to a PO2 ramp (0 to 9.3 kPa) or absolute anoxia, reacted rapidly, reversibly and reproducibly. Under sustained anoxia, ventricular activity stopped after 3.8±0.7 mins (n=4) and then resumed intermittently in the form of tachycardic bursts. Brief anoxia (1 min) provoked tachycardia followed by bradycardia, induced contracture, depressed contractility and retarded atrioventricular propagation. Upon reoxygenation, ventricular contractions ceased suddently for 20±11 s (n=5), whereas a residual atrial activity could persist. The duration of this arrest and the rate of recovery depended on duration of the preceding anoxia. Such a dysfunction constitutes the embryonic analogue of the oxygen paradox observed in adult hearts. Initial impulses, including arrhythmic activity, originated exclusively from the atrium, and no ventricular ectopic beats were detected whatever the conditions of oxygenation. CONCLUSIONS: This in vitro model seems promising for studying the pathophysiological mechanisms associated with hypoxia and reoxygenation in the developing heart.
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Liddle's syndrome is a monogenic form of hypertension caused by mutations in the PY motif of the COOH terminus of beta- and gamma-epithelial Na+ channel (ENaC) subunits. These mutations lead to retention of active channels at the cell surface. Because of the critical role of this PY motif in the stability of ENaCs at the cell surface, we have investigated its contribution to the ENaC response to aldosterone and vasopressin. Mutants of the PY motif in beta- and gamma-ENaC subunits (beta-Y618A, beta-P616L, beta-R564stop, and gamma-K570stop) were stably expressed by retroviral gene transfer in a renal cortical collecting duct cell line (mpkCCDcl4), and transepithelial Na+ transport was assessed by measurements of the benzamil-sensitive short-circuit current (Isc). Cells that express ENaC mutants of the PY motif showed a five- to sixfold higher basal Isc compared with control cells and responded to stimulation by aldosterone (10(-6) M) or vasopressin (10(-9) M) with a further increase in Isc. The rates of the initial increases in Isc after aldosterone or vasopressin stimulation were comparable in cells transduced with wild-type and mutant ENaCs, but reversal of the effects of aldosterone and vasopressin was slower in cells that expressed the ENaC mutants. The conserved sensitivity of ENaC mutants to stimulation by aldosterone and vasopressin together with the prolonged activity at the cell surface likely contribute to the increased Na+ absorption in the distal nephron of patients with Liddle's syndrome.
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OBJECTIVE: Methylphenidate is prescribed for children and adolescents to treat ADHD. As in many Western countries, the increase in methylphenidate consumption is a public concern in Switzerland. The article discusses the authors' assessment of prescription prevalence in 2002 and 2005 for school-aged children in the canton of Vaud. METHOD: Pharmacy prescription information is available from the regional public health authority. Descriptive analyses are conducted on an anonymized database of the years 2002 and 2005. Data for each year are compared to assess trends in methylphenidate prescription prevalence. RESULTS: The findings show an increase from 0.74% to 1.02% in the number of prescriptions for 5- to 14-year-old children, particularly in prescriptions for girls. Data also show important geographical differences in prescription. CONCLUSION: The prevalence of methylphenidate prescription is lower in Switzerland than other Western countries, particularly the United States. However, some aspects of prevalence are similar, including the increase per year, demographics, and geographic characteristics.
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The relationship between blood pressure (BP) and coffee is of major interest given its widespread consumption and the public health burden of high BP. Yet, there is no specific recommendation regarding coffee intake in existing hypertension guidelines. The lack of a definitive understanding of the BP-coffee relationship is partially attributable to issues that we discuss in this review, issues such as acute vs. chronic effects, genetic and smoking effect modifications, and coffee vs. caffeine effects. We also present evidence from meta-analyses of studies on the association of BP with coffee intake. The scope of this review is limited to the latest advances published with a specific focus on caffeine, acknowledging that caffeine is only one among numerous components in coffee that may influence BP. Finally, considering the state of the research, we propose a mechanism by which the CYP1A2 gene and enzyme influence BP via inhibition of the adenosine receptor differentially in smokers and non-smokers.
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The aim of this study was to extract multi-parametric measures characterizing different features of sit-to-stand (Si-St) and stand-to-sit (St-Si) transitions in older persons, using a single inertial sensor attached to the chest. Investigated parameters were transition's duration, range of trunk tilt, smoothness of transition pattern assessed by its fractal dimension, and trunk movement's dynamic described by local wavelet energy. A measurement protocol with a Si-St followed by a St-Si postural transition was performed by two groups of participants: the first group (N=79) included Frail Elderly subjects admitted to a post-acute rehabilitation facility and the second group (N=27) were healthy community-dwelling elderly persons. Subjects were also evaluated with Tinetti's POMA scale. Compared to Healthy Elderly persons, frail group at baseline had significantly longer Si-St (3.85±1.04 vs. 2.60±0.32, p=0.001) and St-Si (4.08±1.21 vs. 2.81±0.36, p=0.001) transition's duration. Frail older persons also had significantly decreased smoothness of Si-St transition pattern (1.36±0.07 vs. 1.21±0.05, p=0.001) and dynamic of trunk movement. Measurements after three weeks of rehabilitation in frail older persons showed that smoothness of transition pattern had the highest improvement effect size (0.4) and discriminative performance. These results demonstrate the potential interest of such parameters to distinguish older subjects with different functional and health conditions.