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1.
Snoring and sleep apnea-hypopnea syndrome (SAHS) are two disorders of considerable relevance due to their high prevalence in the general population and their notable morbidity and mortality, particularly in association with their harmful effects on the cardiovascular system. As well as sex, age, weight, craniofacial malformations, alcohol consumption, and use of hypnotic drugs, it has been suggested that smoking may be a risk factor for developing sleep-disordered breathing. While there is solid evidence for the independent association between snoring and smoking in both children and adults, it is still unclear whether smoking constitutes an independent risk factor for developing SAHS, despite the many studies carried out to assess this link. This is probably because the association, if it exists, is very weak.  相似文献   
2.
BACKGROUND: Executive dysfunctions have been studied as a potential endophenotype associated with the genetic basis of autism. Given that recent findings from clinical and molecular genetic studies suggest that autism and obsessive-compulsive disorder (OCD) could share a common pattern of heritability, we assessed executive functions as a possible common cognitive endophenotype in unaffected family members of individuals with either autism or OCD. METHODS: Five tests assessing executive functions (Tower of London, verbal fluency, design fluency, trail making and association fluency) were proposed to 58 unaffected first-degree relatives (parents and siblings) of probands with autism and 64 unaffected first-degree relatives of OCD patients. Results were compared with those of 47 healthy controls matched for age, sex, and level of education. RESULTS: In the Tower of London test, both groups of unaffected relatives showed significantly lower scores and longer response times compared with controls. No differences were observed between autism and OCD relatives and healthy controls in the four other tasks (verbal fluency, design fluency, trail making test and association fluency). CONCLUSIONS: Our findings show the existence of executive dysfunction in the unaffected first-degree relatives of probands with OCD, similar to those observed in the relatives of patients with autism. These results support and extend previous cognitive studies on probands indicating executive dysfunctions in autism and OCD. Planning and working memory processes could thus represent a common cognitive endophenotype in autism and OCD that could help in the identification of genes conferring vulnerability to these disorders.  相似文献   
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OBJECTIVE: To evaluate the effectiveness of a special course on environmental health and dengue, given to primary school students and intended to promote behavioral changes in the mothers of those students that would lead to the safe handling of water, adequate disposal of trash, and control of household breeding sites of Aedes aegypti, the mosquito vector for dengue. METHODS: In the period from April to November 2002 a community field trial was carried out that included four public schools in the city of Comayaguela, Honduras. Two of the schools formed the intervention group, and the two others made up the comparison or control group. The data collection activities before and after the intervention included knowledge tests for the schoolchildren and the teachers; surveys of the knowledge, attitudes, and practices of the students' mothers; entomological surveys (systematic checking in order to find water containers, to search for mosquito larvae) in the homes of the schoolchildren; in-depth interviews with the students' mothers; observation in the classrooms; and postintervention focus group with the teachers. RESULTS: During the intervention period the largest epidemic of classical dengue ever in the history of Tegucigalpa, the capital of Honduras, occurred. That event prompted the Secretariat of Health to undertake large-scale control activities. In the two intervention schools there was a significant increase in the students' knowledge of the following three variables: dengue caused by a virus, life cycle of the vector, and reduction of breeding sites, which is the most effective measure for controlling the vector (P < 0.0001 for all those increases in knowledge). There were also significant increases in the knowledge of the same variables among the teachers in the intervention schools: dengue caused by a virus (P = 0.03), life cycle of the vector (P = 0.01), and reduction of breeding sites (P = 0.004). Reducing the number of breeding sites as being the best measure for controlling Aedes aegypti was the knowledge variable that showed the greatest change among the mothers in the intervention group (P = 0.02). The values for two of the entomological indices (the House index and the Breteau index) were better in the intervention group than in the control group, but the difference was not statistically significant. However, there was a statistically significant difference in the Breteau index values between the two control group schools and the one intervention school where the education course was implemented more adequately than in the other intervention school. CONCLUSIONS: The application of educational interventions directed to schoolchildren, as a part of a comprehensive plan for controlling Aedes aegypti, is an effective way to raise the awareness of teachers and parents with respect to the problem of dengue, and it also helps in encouraging family members to be involved in reducing breeding sites in the home. In moving to control the dengue vector, this strategy should take into consideration the involvement not only of families but also of civic and public institutions in the community. Given our results, it appears that this approach of using a special course for schoolchildren can constitute a fundamental pillar in the strategy for integrated dengue control.  相似文献   
4.
Androgen insensitivity syndrome (AIS) is an X-linked recessive genetic syndrome that occurs as result of an androgen receptor mutation; it affects the normal masculinization process in chromosomal male patients. More than 900 androgen receptor mutations that can lead to AIS have been identified. The complete androgen insensitivity is characterized by a total lack of response to androgens, usually in patients with 46XY karyotype but with feminine phenotype. Primary amenorrhoea and inguinal swellings in female patients are the main signs that could raise suspicion for this syndrome. Patients with partial androgen insensitivity have ambiguous genitalia at birth and gynecomastia during puberty, whereas those with mild androgen insensitivity present a normal male phenotype but altered spermatogenesis during adulthood and pubertal gynecomastia. The diagnosis of AIS often proves to be a challenge; its management is complex and requires a multidisciplinary approach to meet decision-making challenges in sex assignment, fertility and timing of gonadectomy, psychological outcomes and genetic counselling.  相似文献   
5.
In chronic kidney disease, systemic inflammation and high serum phosphate (P) promote the de-differentiation of vascular smooth muscle cells (VSMC) to osteoblast-like cells, increasing the propensity for medial calcification and cardiovascular mortality. Vascular microRNA-145 (miR-145) content is essential to maintain VSMC contractile phenotype. Because vitamin D induces aortic miR-145, uremia and high serum P reduce it and miR-145 directly targets osteogenic osterix in osteoblasts, this study evaluated a potential causal link between vascular miR-145 reductions and osterix-driven osteogenic differentiation and its counter-regulation by vitamin D. Studies in aortic rings from normal rats and in the rat aortic VSMC line A7r5 exposed to calcifying conditions corroborated that miR-145 reductions were associated with decreases in contractile markers and increases in osteogenic differentiation and calcium (Ca) deposition. Furthermore, miR-145 silencing enhanced Ca deposition in A7r5 cells exposed to calcifying conditions, while miR-145 overexpression attenuated it, partly through increasing α-actin levels and reducing osterix-driven osteogenic differentiation. In mice, 14 weeks after the induction of renal mass reduction, both aortic miR-145 and α-actin mRNA decreased by 80% without significant elevations in osterix or Ca deposition. Vitamin D treatment from week 8 to 14 fully prevented the reductions in aortic miR-145 and attenuated by 50% the decreases in α-actin, despite uremia-induced hyperphosphatemia. In conclusion, vitamin D was able to prevent the reductions in aortic miR-145 and α-actin content induced by uremia, reducing the alterations in vascular contractility and osteogenic differentiation despite hyperphosphatemia.  相似文献   
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ObjectivesTo determine the association between the nuclear respiratory factor 2 (NRF-2) polymorphisms and elite athletic performance.DesignWe compared the genotype and allele frequencies of the NRF-2 A/C (rs12594956), NRF-2 A/G (rs7181866), and NRF-2 C/T (rs8031031) polymorphisms between world-class endurance athletes (n = 89), elite power-oriented athletes (n = 38), and non-athletic controls (n = 110) of the same Caucasian (Spanish) origin.MethodsGenomic DNA was extracted from peripheral EDTA-treated, anti-coagulated blood using a standard protocol. Genotyping was performed using polymerase chain reaction (PCR).ResultsThe frequency of the AA genotype of the NRF-2 A/C (rs12594956) polymorphism was significantly higher in endurance athletes compared with power athletes (P < 0.01) and controls (P < 0.01) (48% vs. 13% and 21%, respectively). The likelihood of having the AA (rs12594956) genotype was higher in elite endurance athletes compared with controls [odds ratio (OR): 3.536, 95% confidence interval (CI): 1.903–6.571] and elite power athletes (OR: 6.170, 95%CI: 2.206–17.253).ConclusionsOur results suggest that the NRF-2 A/C polymorphism might belong to a growing group of polymorphisms associated with endurance performance at the elite level. However, it is important to replicate these findings in other groups of elite athletes using larger sample sizes.  相似文献   
9.
Background  Reversal of ischemia after myocardial infarction by revascularization is worth-while only if viability exists in a sufficiently large portion of the left ventricle. Methods and Results  To determine myocardial hypoperfusion reversibility and its influence on segmental and global function, we studied 50 patients after myocardial infarction. Three technetium 99m-tetrofosmin scintigraphies were performed: 1 at rest, 1 after 0.6 mg sublingual nitroglycerin (NTG), and 1 after injection at peak stress. First-pass multigated radionuclide angiography was obtained at rest and after NTG. Each patient also underwent a stress redistribution-reinjection thallium-201 scintigraphy. During stress 99mTc-tetrofosmin, 104 segments had normal uptake, 51 showed moderately reduced uptake, and 186 had severely reduced uptake. Of these 186 segments, 33 (18%) improved at rest, and 41 (22%) improved only after NTG. Fifty-nine (79%) of these segments with improved uptake were also found to have reversible defects on 201Tl imaging. In the 26 patients with ventricular dysfunction, a 73% agreement was found between the functional and 99mTc-tetrofosmin uptake post-NTG improvement, whereas a 69% agreement was found with thallium reinjection. No significant differences were seen between 99mTc-tetrofosmin and 201Tl imaging. Conclusion  Nitroglycerin administration during 99mTc-tetrofosmin scintigraphy improves the detection of myocardium with reversible hypoperfusion in patients with a previous myocardial infarction.  相似文献   
10.
Staphylococcal scalded skin syndrome (SSSS) is a rare toxin-mediated condition caused by Staphylococcus aureus, which causes blistering and desquamation of the skin. Between November 2005 and April 2006, four children were admitted to critical care beds in the South West Regional Paediatric Burns Unit because of SSSS affecting more than 50% of the body surface area. Details of these cases are presented, highlighting the potential severity of the condition. The cases also illustrate that fluid overload is a common complication of the condition, despite hypovolaemia being the more obvious risk, and that both hyponatraemia and leukopenia are frequent findings. These summaries clearly demonstrate the need for paediatric critical care in a tertiary burns unit for children with SSSS affecting a large proportion of the body surface area. The cluster of admissions prompted us to write a management protocol for children with severe SSSS and a summary of this is provided. Most children with SSSS will initially present to general paediatric units, where mild cases will be managed, but severe cases should be promptly referred to a tertiary paediatric burns unit for multi-disciplinary care in a critical care environment.  相似文献   
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