216 research outputs found
Bucindolol: A Pharmacogenomic Perspective on Its Use in Chronic Heart Failure
Bucindolol is a non-selective β-adrenergic receptor blocker with α-1 blocker properties and mild intrinsic sympatholytic activity. The Beta-Blocker Evaluation of Survival Trial (BEST), which is the largest clinical trial of bucindolol in patients with heart failure, was terminated prematurely and failed to show an overall mortality benefit. However, benefits on cardiac mortality and re-hospitalization rates were observed in the BEST trial. Bucindolol has not shown benefits in African Americans, those with significantly low ejection fraction and those in NYHA class IV heart failure. These observations could be due to the exaggerated sympatholytic response to bucindolol in these sub-groups that may be mediated by genetic polymorphisms or changes in gene regulation due to advanced heart failure. This paper provides a timely clinical update on the use of bucindolol in chronic heart failure
Arsenic-gene interactions and beta-cell function in the Strong Heart Family Study
We explored arsenic-gene interactions influencing pancreatic beta-cell activity in the Strong Heart Family Study (SHFS). We considered 42 variants selected for associations with either beta-cell function (31 variants) or arsenic metabolism (11 variants) in the SHFS. Beta-cell function was calculated as homeostatic model - beta corrected for insulin resistance (cHOMA-B) by regressing homeostatic model – insulin resistance (HOMA-IR) on HOMA-B and adding mean HOMA-B. Arsenic exposure was dichotomized at the median of the sum of creatinine-corrected inorganic and organic arsenic species measured by high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). Additive GxE models for cHOMA-B were adjusted for age and ancestry, and accounted for family relationships. Models were stratified by center (Arizona, Oklahoma, North Dakota and South Dakota) and meta-analyzed. The two interactions between higher vs. lower arsenic and SNPs for cHOMA-B that were nominally significant at P < 0.05 were with rs10738708 (SNP overall effect −3.91, P = 0.56; interaction effect with arsenic −31.14, P = 0.02) and rs4607517 (SNP overall effect +16.61, P = 0.03; interaction effect with arsenic +27.02, P = 0.03). The corresponding genes GCK and TUSC1 suggest oxidative stress and apoptosis as possible mechanisms for arsenic impacts on beta-cell function. No interactions were Bonferroni-significant (1.16 × 10−3). Our findings are suggestive of oligogenic moderation of arsenic impacts on pancreatic β-cell endocrine function, but were not Bonferroni-significant
Genetic analysis of hsCRP in American Indians: The Strong heart family study
Background Increased serum levels of C-reactive protein (CRP), an important component of the innate immune response, are associated with increased risk of cardiovascular disease (CVD). Multiple single nucleotide polymorphisms (SNP) have been identified which are associated with CRP levels, and Mendelian randomization studies have shown a positive association between SNPs increasing CRP expression and risk of colon cancer (but thus far not CVD). The effects of individual genetic variants often interact with the genetic background of a population and hence we sought to resolve the genetic determinants of serum CRP in a number of American Indian populations. Methods The Strong Heart Family Study (SHFS) has serum CRP measurements from 2428 tribal members, recruited as large families from three regions of the United States. Microsatellite markers and MetaboChip defined SNP genotypes were incorporated into variance components, decomposition-based linkage and association analyses. Results CRP levels exhibited significant heritability (h2 = 0.33 ± 0.05, p<1.3 X 10−20). A locus on chromosome (chr) 6, near marker D6S281 (approximately at 169.6 Mb, GRCh38/hg38) showed suggestive linkage (LOD = 1.9) to CRP levels. No individual SNPs were found associated with CRP levels after Bonferroni adjustment for multiple testing (threshold <7.77 x 10−7), however, we found nominal associations, many of which replicate previous findings at the CRP, HNF1A and 7 other loci. In addition, we report association of 46 SNPs located at 7 novel loci on chromosomes 2, 5, 6(2 loci), 9, 10 and 17, with an average of 15.3 Kb between SNPs and all with p-values less than 7.2 X 10−4. Conclusion In agreement with evidence from other populations, these data show CRP serum levels are under considerable genetic influence; and include loci, such as near CRP and other genes, that replicate results from other ethnic groups. These findings also suggest possible novel loci on chr 6 and other chromosomes that warrant further investigation
Reducing medical device alarms by an order of magnitude: A human factors approach
The intensive care unit (ICU) is one of the most technically advanced environments in healthcare, using a multitude of medical devices for drug administration, mechanical ventilation and patient monitoring. However, these technologies currently come with disadvantages, namely noise pollution, information overload and alarm fatigue—all caused by too many alarms. Individual medical devices currently generate alarms independently, without any coordination or prioritisation with other devices, leading to a cacophony where important alarms can be lost amongst trivial ones, occasionally with serious or even fatal consequences for patients. We have called this approach to the design of medical devices the single-device paradigm, and believe it is obsolete in modern hospitals where patients are typically connected to several devices simultaneously. Alarm rates of one alarm every four minutes for only the physiological monitors (as recorded in the ICUs of two hospitals contributing to this paper) degrades the quality of the patient’s healing environment and threatens patient safety by constantly distracting healthcare professionals. We outline a new approach to medical device design involving the application of human factors principles which have been successful in eliminating alarm fatigue in commercial aviation. Our approach comprises the networked-device paradigm, comprehensive alarms and humaniform information displays. Instead of each medical device alarming separately at the patient’s bedside, our proposed approach will integrate, prioritise and optimise alarms across all devices attached to each patient, display information more intuitively and hence increase alarm quality while reducing the number of alarms by an order of magnitude below current levels
Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events
The - oscillation frequency has been measured with a sample of
23 million \B\bar B pairs collected with the BABAR detector at the PEP-II
asymmetric B Factory at SLAC. In this sample, we select events in which both B
mesons decay semileptonically and use the charge of the leptons to identify the
flavor of each B meson. A simultaneous fit to the decay time difference
distributions for opposite- and same-sign dilepton events gives ps.Comment: 7 pages, 1 figure, submitted to Physical Review Letter
Fine mapping and identification of serum urate loci in American Indians: The Strong Heart Family Study
While studies have reported genetic loci affecting serum urate (SU) concentrations, few studies have been conducted in minority populations. Our objective for this study was to identify genetic loci regulating SU in a multigenerational family-based cohort of American Indians, the Strong Heart Family Study (SHFS). We genotyped 162,718 single nucleotide polymorphisms (SNPs) in 2000 SHFS participants using an Illumina MetaboChip array. A genome-wide association analysis of SU was conducted using measured genotype analysis approach accounting for kinships in SOLAR, and meta-analysis in METAL. Our results showed strong association of SU with rs4481233, rs9998811, rs7696092 and rs13145758 (minor allele frequency (MAF) = 25–44%; P < 3 × 10−14) of solute carrier family 2, member 9 (SLC2A9) and rs41481455, rs2231142 and rs1481012 (MAF = 29%; p < 3 × 10−9) of ATP-binding cassette protein, subfamily G, member 2 (ABCG2). Carriers of G alleles of rs9998811, rs4148155 and rs1481012 and A alleles of rs4481233, rs7696092 and rs13145758 and rs2231142 had lower SU concentrations as compared to non-carriers. Genetic analysis of SU conditional on significant SLC2A9 and ABCG2 SNPs revealed new loci, nucleobindin 1 (NUCB1) and neuronal PAS domain protein 4 (NPAS4) (p <6× 10−6). To identify American Indian-specific SNPs, we conducted targeted sequencing of key regions of SLC2A9. A total of 233 SNPs were identified of which 89 were strongly associated with SU (p < 7.1 × 10−10) and 117 were American Indian specific. Analysis of key SNPs in cohorts of Mexican-mestizos, European, Indian and East Asian ancestries showed replication of common SNPs, including our lead SNPs. Our results demonstrate the association of SU with uric acid transporters in a minority population of American Indians and potential novel associations of SU with neuronal-related genes which warrant further investigation
Effect of lactation stage and concurrent pregnancy on milk composition in the bottlenose dolphin
Although many toothed whales (Cetacea: Odontoceti) lactate for 2–3 years or more, it is not known whether milk composition is affected by lactation stage in any odontocete species. We collected 64 pooled milk samples spanning 1–30 months postpartum from three captive bottlenose dolphins Tursiops truncatus. Milks were assayed for water, fat, crude protein (TN × 6.38) and sugar; gross energy was calculated. Ovulation and pregnancy were determined via monitoring of milk progesterone. Based on analysis of changes in milk composition for each individual dolphin, there were significant increases (P<0.05) in fat (in all three dolphins) and crude protein (in two of three), and a decrease (P<0.05) in water (in two of three) over the course of lactation, but the sugar content did not change. In all three animals, the energy content was positively correlated with month of lactation, but the percentage of energy provided by crude protein declined slightly but significantly (P<0.05). At mid-lactation (7–12 months postpartum, n=17), milk averaged 73.0±1.0% water, 12.8±1.0% fat, 8.9±0.5% crude protein, 1.0±0.1% sugar, 1.76±0.09 kcal g−1 (=7.25 kJ g−1) and 30.3±1.3% protein:energy per cent. This protein:energy per cent was surprisingly high compared with other cetaceans and in relation to the growth rates of calves. Milk progesterone indicated that dolphins ovulated and conceived between 413 and 673 days postpartum, following an increase in milk energy density. The significance of these observed compositional changes to calf nutrition will depend on the amounts of milk produced at different stages of lactation, and how milk composition and yield are influenced by sampling procedure, maternal diet and maternal condition, none of which are known
Selective Exposure to Berita Harian Online and Utusan Malaysia Online: The Roles of Surveillance Motivation, Website Usability and Website Attractiveness
News media allows audiences to be selective in determining both their news sources
and type of news stories they read. This study examined factors influencing selective
exposure to the online editions of two mainstream Malaysian newspapers, Berita
Harian and Utusan Malaysia. Using selective exposure theory as the theoretical
lens, this study compared both newspapers in terms of their audiences’ level of
surveillance motivation, and how audiences rate the newspapers’ websites with respect
to usability and attractiveness. This study used a within-subject experimental research
design that exposed 51 subjects to both Berita Harian and Utusan Malaysia online
newspapers. The results of the experiment indicate that Berita Harian and Utusan
Malaysia online were significantly different in terms of website usability; however,
no significant differences were found in terms of surveillance motivation or website
attractiveness between the two newspapers. Further analysis indicate that the only
significant predictor of selective exposure was website usability. This study highlights
the importance of website usability for online newspapers wanting to harness audience
selectivity
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