Citations

The reasons underlying parents' decisions to seek medical evaluations for their mildly ill children are not well understood. This cross-sectional study tracked parents' requests for on-site medical evaluations at a sick child care program. A logistic regression model identified factors associated with parents' decisions to seek medical evaluations for their children based on the data from parent-completed questionnaires. A convenience sample of 196 parents completed all questionnaires; 62 (31.6%) parents sought medical evaluations. Parents were more likely to seek medical evaluations if they were concerned about missing work (odds ratio = 8.6; 95% confidence interval, 3.3-22.0; P = .0001), if they smoked (odds ratio = 3.7; 95% confidence interval, 1.1-12.4; P = .037), or if their spouse's highest educational attainment was some high school (odds ratio = 0.4; 95% confidence interval, 0.1-1.0; P = .044). The data highlight the problems working parents have in accessing health care during usual working hours and the potential value of convenient health care programs.

The National Heart, Lung, and Blood Institute and Office of Rare Diseases at the National Institutes of Health organized a workshop (September 14 to 15, 2006, in Bethesda, Md) to advise on new research directions needed for improved identification and treatment of rare inherited arrhythmias. These included the following: (1) Na + channelopathies; (2) arrhythmias due to K + channel mutations; and (3) arrhythmias due to other inherited arrhythmogenic mechanisms. Another major goal was to provide recommendations to support, enable, or facilitate research to improve future diagnosis and management of inherited arrhythmias. Classifications of electric heart diseases have proved to be exceedingly complex and in many respects contradictory. A new contemporary and rigorous classification of arrhythmogenic cardiomyopathies is proposed. This consensus report provides an important framework and overview to this increasingly heterogeneous group of primary cardiac membrane channel diseases. Of particular note, the present classification scheme recognizes the rapid evolution of molecular biology and novel therapeutic approaches in cardiology, as well as the introduction of many recently described diseases, and is unique in that it incorporates ion channelopathies as a primary cardiomyopathy in consensus with a recent American Heart Association Scientific Statement.

Abstract The rationale behind gene-disease association studies is that genetic variants (polymorphisms) result in alterations in intermediate phenotypes. However, genotype-phenotype correlations have not been established for most polymorphisms. In this study, we correlated genotype data of genes involved in the nucleotide excision repair pathway with mutagen sensitivity phenotype, quantified by benzo(a)pyrene diol epoxide (BPDE)-induced chromatid breaks in peripheral blood lymphocytes in 422 healthy subjects recruited into a twin study that included 138 pairs of monozygotic twins, 51 pairs of dizygotic twins, and 44 siblings. Among a panel of single nucleotide polymorphisms examined, we found that BPDE sensitivity was modified by individual polymorphisms in XPC, RAD23B, and XPA genes. Specific haplotypes and diplotypes of XPC also modified BPDE sensitivity profiles. In addition, a more consistent and stronger correlation was observed between mutagen sensitivity phenotype and the combination of multiple polymorphisms in the nucleotide excision repair pathway. Specifically, when XPC-PAT, XPC Lys939Gln, XPA A23G, and RAD23B Val249Ala were analyzed together, we observed a significant dose-response relationship between increasing mutagen sensitivity with increasing number of adverse alleles: mutagen sensitivity for those carrying zero to two, three to five, and six or more adverse alleles were 0.64, 0.68, and 1.06, respectively (P for trend = 0.008), and the results remained significant after adjusting for multiple comparisons. Using individuals carrying zero to two adverse alleles as the reference group, the risks of being mutagen sensitive (mutagen sensitivity values greater than the median) were 1.05 (95% confidence interval, 0.68-1.64) and 4.48 (95% confidence interval, 1.21-16.61) for those carrying three to five and six or more adverse alleles, respectively. Analyses of the effects of genotype combinations yielded similar results. These findings underscore the importance of assessing the collective effects of a panel of polymorphisms in the same pathway in modulating mutagen sensitivity. As risk assessment for cancer risk is moving toward a multigenic pathway-based approach, future genotype-phenotype correlation studies should also investigate the combined effects of multiple genetic variants. (Cancer Epidemiol Biomarkers Prev 2007;16(10):2065–71)

Mechanical ventilation practice has changed over the past few decades, with tidal volumes (VT) decreasing significantly, especially in patients with acute lung injury (ALI). Patients without acute lung injury are still ventilated with large--and perhaps too large--VT. Studies of ventilator-associated lung injury in subjects without ALI demonstrate inconsistent results. Retrospective clinical studies, however, suggest that the use of large VT favors the development of lung injury in these patients. Side effects associated with the use of lower VT in patients with ALI seem to be minimal. Assuming that this will be the case in patients without ALI/acute respiratory distress syndrome too, the authors suggest that the use of lower VT should be considered in all mechanically ventilated patients whether they have ALI or not. Prospective studies should be performed to evaluate optimal ventilator management strategies for patients without ALI.

Abstract The Janus kinase 2 mutation, JAK2617V>F, is myeloid neoplasm-specific; its presence excludes secondary polycythemia, thrombocytosis, or bone marrow fibrosis from other causes. Furthermore, JAK2617V>F or a JAK2 exon 12 mutation is present in virtually all patients with polycythemia vera (PV), whereas JAK2617V>F also occurs in approximately half of patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF). Therefore, JAK2 mutation screening holds the promise of a decisive diagnostic test in PV while being complementary to histology for the diagnosis of ET and PMF; the combination of molecular testing and histologic review should also facilitate diagnosis of ET associated with borderline thrombocytosis. Accordingly, revision of the current World Health Organization (WHO) diagnostic criteria for PV, ET, and PMF is warranted; JAK2 mutation analysis should be listed as a major criterion for PV diagnosis, and the platelet count threshold for ET diagnosis can be lowered from 600 to 450 × 109/L. The current document was prepared by an international expert panel of pathologists and clinical investigators in myeloproliferative disorders; it was subsequently presented to members of the Clinical Advisory Committee for the revision of the WHO Classification of Myeloid Neoplasms, who endorsed the document and recommended its adoption by the WHO.

We studied the arachidonic acid (AA)-mediated modulation of large-conductance Ca2+-activated K+ (BK) channels in coronary arterial smooth myocytes from lean control and Zucker Diabetic Fatty (ZDF) rats. A total of 1 μmol/l AA enhanced BK current by 274% in lean and by 98% in ZDF rats. After incubation with 10 μmol/l indomethacin, 1 μmol/l AA increased BK currents by 80% in lean and by 70% in ZDF rats. Vasoreactivity studies showed that the dilation of small coronary arteries produced by 1 μmol/l AA was reduced by 44% in ZDF rats. [3H]6-keto-prostagladin F1α ([3H]6-keto-PGF1α,), the stable metabolite of prostacyclin (PGI2), was the major [3H]AA metabolite produced by coronary arteries of lean vessels, but ZDF vessels produced only 15% as much [3H]6-keto-PGF1α. BK channel activation and vasorelaxation by iloprost were similar in lean and ZDF rats. Immunoblots showed a 73% reduction in PGI2 synthase (PGIS) expression in ZDF vessels compared with lean vessels, and there was no change in cyclooxygenase (COX) and BK channel expressions. Real-time PCR studies showed that mRNA levels of PGIS, COX-1, and COX-2 were similar between lean and ZDF vessels. We conclude that PGI2 is the major AA metabolite in lean coronaries, and AA-mediated BK channel activation is impaired in ZDF coronaries due to reduced PGIS activity.

We reviewed the records of pregnant diabetic women attended at Mayo Clinic during the years 1950–79 and matched each nonaborted diabetic pregnancy with two control pregnancies. Abortions occurred in 49 of 277 diabetic pregnancies (17.7%). The relative risk of other adverse outcomes of pregnancy (± 95% confidence interval) in comparison with controls was as follows: perinatal mortality, 7.0 (3.6–13.8); major congenital birth defects, 6.3 (2.8–14.2); and respiratory distress, 9.0 (4.5–17.9). Diabetic ketoacidosis resulted in fetal death in 5 of 18 cases. Patients with mean fasting blood glucose levels of ≤ 140 mg/dl had a perinatal mortality of 81 per 1000 births and an incidence of respiratory distress and congenital birth defects of 18.9% and 9.9%, respectively. Patients with mean blood glucose levels > 140 mg/dl had corresponding rates of 306 per 1000, 20.4%, and 11.2%, respectively. Hydramnios occurred almost exclusively in diabetic women, and its presence was associated with a twofold increase in the frequency of perinatal death. Analysis of diabetic pregnancy outcome by decade showed no appreciable decrease in the occurrence of perinatal mortality, congenital birth defects, or respiratory distress over the 30-yr period.

Epidemiologic studies strongly associate eosinophilia-myalgia syndrome (EMS) with ingestion of tryptophan containing a contaminant ("peak E"). Prior reports have suggested that peak E is the di-tryptophan Nα-animal of acetaldehyde. Spectral and chemical studies now demonstrate that peak E is 1,1′-ethylidenebis[tryptophan]. This novel amino acid may be the etiological agent responsible for EMS, or it may be a marker of a still unidentified causal agent.