Nomograms to predict normal aortic root diameter for body surface area (BSA) in broad ranges of age have been widely used but are limited by lack of consideration of gender effects, jumps in upper ...limits of aortic diameter among age strata, and data from older teenagers. Sinus of Valsalva diameter was measured by American Society of Echocardiography convention in normal-weight, nonhypertensive, nondiabetic subjects ≥15 years old without aortic valve disease from clinical or population-based samples. Analyses of covariance and linear regression with assessment of residuals identified determinants and developed predictive models for normal aortic root diameter. In 1,207 apparently normal subjects ≥15 years old (54% women), aortic root diameter was 2.1 to 4.3 cm. Aortic root diameter was strongly related to BSA and height (r = 0.48 for the 2 comparisons), age (r = 0.36), and male gender (+2.7 mm adjusted for BSA and age, p <0.001 for all comparisons). Multivariable equations using age, gender, and BSA or height predicted aortic diameter strongly (R = 0.674 for the 2 comparisons, p <0.001) with minimal relation of residuals to age or body size: for BSA 2.423 + (age years × 0.009) + (BSA square meters × 0.461) − (gender 1 = man, 2 = woman × 0.267), SEE 0.261 cm; for height 1.519 + (age years × 0.010) + (height centimeters × 0.010) − (gender 1 = man, 2 = woman × 0.247), SEE 0.215 cm. In conclusion, aortic root diameter is larger in men and increases with body size and age. Regression models incorporating body size, age, and gender are applicable to adolescents and adults without limitations of previous nomograms.
Abstract
The Submillimetre Common User Bolometer Array 2 (SCUBA-2) is the James Clerk Maxwell Telescope’s continuum imager, operating simultaneously at 450 and 850
μ
m. SCUBA-2 was commissioned in ...2009–2011, and since that time, regular observations of point-like standard sources have been performed whenever the instrument is in use. Expanding the calibrator observation sample by an order of magnitude compared to previous work, in this paper we derive updated opacity relations at each wavelength for a new atmospheric extinction correction, analyze the Flux Conversion Factors used to convert instrumental units to physical flux units as a function of date and observation time, present information on the beam profiles for each wavelength, and update secondary calibrator source fluxes. Between 07:00 and 17:00 UTC, the portion of the night that is most stable to temperature gradients that cause dish deformation, the total flux uncertainty and the peak flux uncertainty measured at 450
μ
m are found to be 14% and 17%, respectively. Measured at 850
μ
m, the total flux and peak flux uncertainties are 6% and 7%, respectively. The analysis presented in this work is applicable to all SCUBA-2 projects observed since 2011.
Telomeres play a central role in cellular aging, and shorter telomere length has been associated with age-related disorders including diabetes. However, a causal link between telomere shortening and ...diabetes risk has not been established. In a well-characterized longitudinal cohort of American Indians participating in the Strong Heart Family Study, we examined whether leukocyte telomere length (LTL) at baseline predicts incident diabetes independent of known diabetes risk factors. Among 2,328 participants free of diabetes at baseline, 292 subjects developed diabetes during an average 5.5 years of follow-up. Compared with subjects in the highest quartile (longest) of LTL, those in the lowest quartile (shortest) had an almost twofold increased risk of incident diabetes (hazard ratio HR 1.83 95% CI 1.26-2.66), whereas the risk for those in the second (HR 0.87 95% CI 0.59-1.29) and the third (HR 0.95 95% CI 0.65-1.38) quartiles was statistically nonsignificant. These findings suggest a nonlinear association between LTL and incident diabetes and indicate that LTL could serve as a predictive marker for diabetes development in American Indians, who suffer from disproportionately high rates of diabetes.
Abstract Background High rates of posttraumatic stress disorder (PTSD) and depressive symptoms have been observed in earthquake survivors from less developed areas of the world. This study, conducted ...three years after the 2005 Pakistan earthquake, aimed to identify potentially protective psychosocial factors associated with lower PTSD and depressive symptom levels. Methods Adult earthquake survivors ( N =200) were recruited from affected areas in Northwestern Pakistan and completed self-report questionnaires measuring PTSD and depressive symptoms, positive and negative affect, and four psychosocial variables (purpose in life, positive and negative religious coping, and social support). Results Sixty five percent of participants met criteria for probable PTSD. Purpose in life was associated with lower symptom levels and higher positive emotions. A form of negative religious coping (feeling punished by God for one’s sins or lack of spirituality) was associated with higher symptom levels and negative emotions. Higher perceived social support was associated with higher positive emotions. Other significant relationships were also identified. Limitations Limitations include the recruitment of a sample of convenience, a modest sample size, and the cross-sectional nature of the study. Conclusions Findings suggest that some psychosocial factors may be protective across cultures, and that the use of negative religious coping is associated with poorer mental health outcomes in earthquake survivors. This study can inform preventive and treatment interventions for earthquake survivors in Pakistan and other less industrialized countries as they develop mental health care services.
Most protostars have luminosities that are fainter than expected from steady accretion over the protostellar lifetime. The solution to this problem may lie in episodic mass accretion-prolonged ...periods of very low accretion punctuated by short bursts of rapid accretion. However, the timescale and amplitude for variability at the protostellar phase is almost entirely unconstrained. In A James Clerk Maxwell Telescope/SCUBA-2 Transient Survey of Protostars in Nearby Star-forming Regions, we are monitoring monthly with SCUBA-2 the submillimeter emission in eight fields within nearby ( < 500 pc) star-forming regions to measure the accretion variability of protostars. The total survey area of ∼1.6 deg2 includes ∼105 peaks with peaks brighter than 0.5 Jy/beam (43 associated with embedded protostars or disks) and 237 peaks of 0.125-0.5 Jy/beam (50 with embedded protostars or disks). Each field has enough bright peaks for flux calibration relative to other peaks in the same field, which improves upon the nominal flux calibration uncertainties of submillimeter observations to reach a precision of ∼2%-3% rms, and also provides quantified confidence in any measured variability. The timescales and amplitudes of any submillimeter variation will then be converted into variations in accretion rate and subsequently used to infer the physical causes of the variability. This survey is the first dedicated survey for submillimeter variability and complements other transient surveys at optical and near-IR wavelengths, which are not sensitive to accretion variability of deeply embedded protostars.
Dyslipidemia is an important risk factor for hypertension and cardiovascular disease. Standard lipid panel cannot reflect the complexity of blood lipidome. The associations of individual lipid ...species with hypertension remain to be determined in large-scale epidemiological studies, especially in a longitudinal setting.
Using liquid chromatography-mass spectrometry, we repeatedly measured 1542 lipid species in 3699 fasting plasma samples at 2 visits (1905 at baseline, 1794 at follow-up, ~5.5 years apart) from 1905 unique American Indians in the Strong Heart Family Study. We first identified baseline lipids associated with prevalent and incident hypertension, followed by replication of top hits in Europeans. We then conducted repeated measurement analysis to examine the associations of changes in lipid species with changes in systolic blood pressure, diastolic blood pressure, and mean arterial pressure. Network analysis was performed to identify lipid networks associated with the risk of hypertension.
Baseline levels of multiple lipid species, for example, glycerophospholipids, cholesterol esters, sphingomyelins, glycerolipids, and fatty acids, were significantly associated with both prevalent and incident hypertension in American Indians. Some lipids were confirmed in Europeans. Longitudinal changes in multiple lipid species, for example, acylcarnitines, phosphatidylcholines, fatty acids, and triacylglycerols, were significantly associated with changes in blood pressure measurements. Network analysis identified distinct lipidomic patterns associated with the risk of hypertension.
Baseline plasma lipid species and their longitudinal changes are significantly associated with hypertension development in American Indians. Our findings shed light on the role of dyslipidemia in hypertension and may offer potential opportunities for risk stratification and early prediction of hypertension.
Myocardial energetic efficiency (MEE), is a strong predictor of CV events in hypertensive patient and is reduced in patients with diabetes and metabolic syndrome. We hypothesized that severity of ...insulin resistance (by HOMA-IR) negatively influences MEE in participants from the Strong Heart Study (SHS).
We selected non-diabetic participants (n = 3128, 47 ± 17 years, 1807 women, 1447 obese, 870 hypertensive) free of cardiovascular (CV) disease, by merging two cohorts (Strong Heart Study and Strong Heart Family Study, age range 18-93). MEE was estimated as stroke work (SW = systolic blood pressure SBP × stroke volume SV)/"double product" of SBP × heart rate (HR), as an estimate of O
consumption, which can be simplified as SV/HR ratio and expressed in ml/sec. Due to the strong correlation, MEE was normalized by left ventricular (LV) mass (MEEi).
Linear trend analyses showed that with increasing quartiles of HOMA-IR patients were older, more likely to be women, obese and hypertensive, with a trend toward a worse lipid profile (all p for trend < 0.001), progressive increase in LV mass index, stroke index and cardiac index and decline of wall mechanics (all p < 0.0001). In multivariable regression, after adjusting for confounders, and including a kinship coefficient to correct for relatedness, MEEi was negatively associated with HOMA-IR, independently of significant associations with age, sex, blood pressure, lipid profile and central obesity (all p < 0.0001).
Severity of insulin resistance has significant and independent negative impact on myocardial mechano-energetic efficiency in nondiabetic individual from a population study of American Indians. Trial registration number NCT00005134, Name of registry: Strong Heart Study, URL of registry: https://clinicaltrials.gov/ct2/show/NCT00005134 , Date of registration: May 25, 2000, Date of enrolment of the first participant to the trial: September 1988.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We previously demonstrated stronger relations of central vs. brachial blood pressure, particularly pulse pressure, to carotid artery hypertrophy and extent of atherosclerosis. Data regarding the ...relative impacts of central and brachial pressures on left ventricular hypertrophy and geometry are limited.
Echocardiography and radial applanation tonometry were performed in American Indian participants in the 4th Strong Heart Study examination. Left ventricular mass was calculated using an anatomically validated formula and adjusted for height. Brachial blood pressure was measured according to a standardized protocol. Central pressures were derived using a generalized transfer function.
Of 2585 participants in the analysis, 60% were women, 21% had diabetes and 33% were hypertensive; the mean age was 40 +/- 17 years. All blood pressure variables were significantly related to left ventricular absolute and relative wall thicknesses and left ventricular mass index (all P < 0.001), with considerable variation in correlation coefficients (r = 0.135-0.432). Central and brachial systolic pressures were uniformly more strongly related to left ventricular wall thicknesses, diastolic diameter and mass index than their respective pulse pressures (all P < 0.005 by z statistics). Left ventricular relative wall thickness and mass index were more strongly related to central than brachial pressures.
Left ventricular hypertrophy is more strongly related to systolic pressure than to pulse pressure. Furthermore central pressures are more strongly related than brachial pressures to concentric left ventricular geometry. These data suggest that absolute (systolic) pressure is more important in stimulating left ventricular hypertrophy and remodeling, whereas pulsatile stress (pulse pressure) is more important in causing vascular hypertrophy and atherosclerosis.
High arsenic exposure has been related to diabetes, but at low-moderate levels the evidence is mixed. Arsenic metabolism, which is partly genetically controlled and may rely on certain B vitamins, ...plays a role in arsenic toxicity.
We evaluated the prospective association of arsenic exposure and metabolism with type 2 diabetes and insulin resistance.
We included 1,838 American Indian men and women free of diabetes (median age, 36 y). Arsenic exposure was assessed as the sum of inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) urine concentrations (ΣAs). Arsenic metabolism was evaluated by the proportions of iAs, MMA, and DMA over their sum (iAs%, MMA%, and DMA%). Homeostasis model assessment for insulin resistance (HOMA2-IR) was measured at baseline and follow-up visits. Incident diabetes was evaluated at follow-up.
Median ΣAs, iAs%, MMA%, and DMA% was 4.4 μg/g creatinine, 9.5%, 14.4%, and 75.6%, respectively. Over 10,327 person-years of follow-up, 252 participants developed diabetes. Median HOMA2-IR at baseline was 1.5. The fully adjusted hazard ratio 95% confidence interval (CI) for incident diabetes per an interquartile range increase in ΣAs was 1.57 (95% CI: 1.18, 2.08) in participants without prediabetes at baseline. Arsenic metabolism was not associated with incident diabetes. ΣAs was positively associated with HOMA2-IR at baseline but negatively with HOMA2-IR at follow-up. Increased MMA% was associated with lower HOMA2-IR when either iAs% or DMA% decreased. The association of arsenic metabolism with HOMA2-IR differed by B-vitamin intake and
genetics variants.
Among participants without baseline prediabetes, arsenic exposure was associated with incident diabetes. Low MMA% was cross-sectional and prospectively associated with higher HOMA2-IR. Research is needed to confirm possible interactions of arsenic metabolism with B vitamins and
variants on diabetes risk. https://doi.org/10.1289/EHP2566.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
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