We have examined prospectively whether the tolerance-hyperbaric test (THT), combined approach of establishing tolerance intervals for the circadian variability of blood pressure (BP) as a function of gestational age, and then computing the hyperbaric index (HBI, area of BP excess above the upper limit of the interval) by comparison of any patient's BP profile with those intervals, provides high sensitivity for the early identification of pregnant women who subsequently will develop hypertensive complications in pregnancy. We analyzed 2,014 BP series obtained from 176 women with uncomplicated pregnancies and 121 women who developed gestational hypertension or preeclampsia (gestational hypertension and proteinuria, above 300 mg/24 hours in urine). BP was sampled at half-hour intervals during the day and hourly during the night for 48 hours with an ABPM-630 Colin device once every 4 weeks from the first visit to the hospital (mostly before 14 weeks of gestation) until delivery. Circadian 90% tolerance limits for BP were computed as a function of trimester of gestation from 497 series previously sampled from a reference group of 189 normotensive pregnant women [Hermida RC, et al. J Perinat Med 1997;25:237–253]. Sensitivity of the THT was 91% for women sampled during the first trimester of gestation, and increased up to 99% in the third trimester. Specificity for a threshold HBI value for diagnosis of 15 mmHgXhour obtained from previous studies [Hermida RC, et al. Hypertension 1998;31:83–88] was above 99% in all trimesters. The positive and negative predictive values were above 95% in all trimesters. The test provided, on the average, an early identification of gestational hypertension and preeclampsia 23 weeks prior to the clinical confirmation of the disease. The THT, now validated prospectively in women systematically sampled by ambulatory monitoring throughout pregnancy, represents a reproducible, noninvasive, and high sensitivity test for the very early identification of subsequent gestational hypertension and preeclampsia.
Abstract Here, López-Cortegano and Caballero carried out a meta-analysis using records from a database of genome-wide studies in order to investigate the nature of missing heritability in humans... Thousands of genes responsible for many diseases and other common traits in humans have been detected by Genome Wide Association Studies (GWAS) in the last decade. However, candidate causal variants found so far usually explain only a small fraction of the heritability estimated by family data. The most common explanation for this observation is that the missing heritability corresponds to variants, either rare or common, with very small effect, which pass undetected due to a lack of statistical power. We carried out a meta-analysis using data from the NHGRI-EBI GWAS Catalog in order to explore the observed distribution of locus effects for a set of 42 complex traits and to quantify their contribution to narrow-sense heritability. With the data at hand, we were able to predict the expected distribution of locus effects for 16 traits and diseases, their expected contribution to heritability, and the missing number of loci yet to be discovered to fully explain the familial heritability estimates. Our results indicate that, for 6 out of the 16 traits, the additive contribution of a great number of loci is unable to explain the familial (broad-sense) heritability, suggesting that the gap between GWAS and familial estimates of heritability may not ever be closed for these traits. In contrast, for the other 10 traits, the additive contribution of hundreds or thousands of loci yet to be found could potentially explain the familial heritability estimates, if this were the case. Computer simulations are used to illustrate the possible contribution from nonadditive genetic effects to the gap between GWAS and familial estimates of heritability.
Abstract ModelTest-NG is a re-implementation from scratch of jModelTest and ProtTest, two popular tools for selecting the best-fit nucleotide and amino acid substitution models, respectively. ModelTest-NG is one to two orders of magnitude faster than jModelTest and ProtTest but equally accurate, and introduces several new features, such as ascertainment bias correction, mixture and FreeRate models, or the automatic processing of partitioned datasets. ModelTest-NG is available under a GNU GPL3 license at https://github.com/ddarriba/modeltest .
ABSTRACT: Samples of ultra heat‐treated (UHT) milk (whole, semiskimmed, and skimmed milk, whole milk with cinnamon and lemon flavors, and semiskimmed milk with cocoa) were collected. Growth of E. coli O157:H7 was detected in whole milk at 4 °C (generation time 0.89 d) and in all milks at 20 °C during the first 24 h. Growth of nonpathogenice. coli was detected in milk samples without flavors during the same period of time. The fastest death time of E. coli O157:H7 was detected in whole milk with cinnamon and lemon at 4 °C (−1.35 d) The nonpathogenic strain showed the fastest death time in skimmed milk at 20 °C.
Poly(vinylpyrrolidone) (PVP) is a polymer capable of complexing and stabilizing Ag and Au nanoparticles formed through the reduction of Ag+ or AuCl4- ions with N,N-dimethylformamide. The reduction can be efficiently performed both at reflux and under microwave irradiation, but each of these methods leads to different nanoparticle morphology and colloid stability. The use of microwave irradiation provides an extra degree of control of the reduction process. The use of PVP with different polymer chain lengths leads to particles with similar sizes though with a different degree of stability. The colloids are also stable in ethanol for months, but only marginally stable in water.
The clinical prognostic significance of white coat hypertension (WCH) is still controversial. Although recent longitudinal studies have provided preliminary prognostic data on subjects with WCH as compared to patients with sustained hypertension, the possible relation between WCH and vascular risk is still under debate. The purpose ot this study was to compare the circadian pattern of blood pressure (BP) variability between normotensive abd WCH subjects. We studied 917 subjects (495 men and 422 women), 49.5±14.5 (mean±SD) years of age, with diurnal BP mean below 135/85 for systolic/diastolic BP, and hyperbaric index (area of BP excess above a time-specified tolerance interval) below the previously established threshold for diagnosis of hypertension from data obtained by ambulatory BP monitoring [Hypertension. 2000;35:118–125]. Among those subjects, 407 (235 men and 172 women) were diagnosed with WCH (mean from 6 office BP measurements above 140 or 90 mm Hg for systolic or diastolic BP). BP was measured at 20-min intervals from 07:00 to 23:00 hours and at 30-min intervals at night for 48 consecutive hours. Circadian parameters established by population multiple-component analysis [Chronobiol Int. 1998;15:191–204] were compared between normotensive and WCH subjects by nonparametric testing. Patients with WCH are characterized by a significant increase in systolic (3.4 mm Hg; P<0.001) but not in diastolic BP (−0.4 mm Hg, P=0.238 for comparison of 24-hour mean) as compared to normotensive subjects. Although more pronounced during the diurnally active hours, the differences in systolic BP between normotension and WCH were significant throughout the 24 hours of the day. The largest and most significant difference between groups was found around the clock in pulse pressure (3.8 mm Hg in 24-hour mean, P<0.001). In volunteers studied by 48-hour ambulatory monitoring, WCH is characterized by a significant elevation in systolic BP and, especially, in pulse pressure as compared to normotensive subjects. Increased pulse pressure is an independent marker of cardiovascular risk, mainly for myocardial infarction, congestive heart failure, and cardiovascular deaths. Accordingly, WCH could be associated to a long-term worst prognosis in comparison to true normotension, an issue that deserves further prospective investigation. Am J Hypertens (2004) 17, 41A–42A; doi: 10.1016/j.amjhyper.2004.03.099
