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The phenotypic effect of some single nucleotide polymorphisms (SNPs) depends on their parental origin. We present a novel approach to detect parent-of-origin effects (POEs) in genome-wide genotype data of unrelated individuals. The method exploits increased phenotypic variance in the heterozygous genotype group relative to the homozygous groups. We applied the method to >56,000 unrelated individuals to search for POEs influencing body mass index (BMI). Six lead SNPs were carried forward for replication in five family-based studies (of ∼4,000 trios). Two SNPs replicated: the paternal rs2471083-C allele (located near the imprinted KCNK9 gene) and the paternal rs3091869-T allele (located near the SLC2A10 gene) increased BMI equally (beta = 0.11 (SD), P<0.0027) compared to the respective maternal alleles. Real-time PCR experiments of lymphoblastoid cell lines from the CEPH families showed that expression of both genes was dependent on parental origin of the SNPs alleles (P<0.01). Our scheme opens new opportunities to exploit GWAS data of unrelated individuals to identify POEs and demonstrates that they play an important role in adult obesity.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of nicotinamide adenine dinucleotide (NAD) from adenosine monophosphate (AMP)David R. Walt, Victor M. Rios-Mercadillo, Jacques Auge, and George M. WhitesidesCite this: J. Am. Chem. Soc. 1980, 102, 26, 7805–7806Publication Date (Print):December 1, 1980Publication History Published online1 May 2002Published inissue 1 December 1980https://pubs.acs.org/doi/10.1021/ja00546a041https://doi.org/10.1021/ja00546a041research-articleACS PublicationsRequest reuse permissionsArticle Views626Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Semiconductor nanowires and other semiconducting nanoscale materials configured as field-effect transistors have been studied extensively as biological/chemical (bio/chem) sensors. These nanomaterials have demonstrated high-sensitivity from one- and two-dimensional sensors, although the realization of the ultimate pointlike detector has not been achieved. In this regard, nanoscale p–n diodes are attractive since the device element is naturally localized near the junction, and while nanowire p–n diodes have been widely studied as photovoltaic devices, their applications as bio/chem sensors have not been explored. Here we demonstrate that p–n diode devices can serve as a new and powerful family of highly localized biosensor probes. Designed nanoscale axial p–n junctions were synthetically introduced at the joints of kinked silicon nanowires. Scanning electron microscopy images showed that the kinked nanowire structures were achieved, and electrical transport measurements exhibited rectifying behavior with well-defined turn-on in forward bias as expected for a p–n diode. In addition, scanning gate microscopy demonstrated that the most sensitive region of these nanowires was localized near the kinked region at the p–n junction. High spatial resolution sensing using these p–n diode probes was carried out in aqueous solution using fluorescent charged polystyrene nanobeads. Multiplexed electrical measurements show well-defined single-nanoparticle detection, and experiments with simultaneous confocal imaging correlate directly the motion of the nanobeads with the electrical signals recorded from the p–n devices. In addition, kinked p–n junction nanowires configured as three-dimensional probes demonstrate the capability of intracellular recording of action potentials from electrogenic cells. These p–n junction kinked nanowire devices, which represent a new way of constructing nanoscale probes with highly localized sensing regions, provide substantial opportunity in areas ranging from bio/chem sensing and nanoscale photon detection to three-dimensional recording from within living cells and tissue.

An optical waveguide formed by a suspension of dielectric nanoparticles in a microchannel is described. The suspensions, chosen for their guiding and scattering properties, are silica and polystyrene particles that have diameters of 30–900 nm and are dispersed in water with volume fractions up to 10%. Changing the diameter and concentration of the particles causes the suspensions to transition from Rayleigh to Mie scattering and from single to multiple scattering. The threshold for optical guiding in a waveguide core composed of these suspensions is set by the numerical aperture of the effective refractive-index difference introduced by the suspension and not by the average interparticle distance.

No abstract is provided for this article.

Background: Individuals born preterm are at risk of later developmental problems and long‐term morbidities. There is conflicting evidence regarding musculoskeletal pain in young adulthood. We investigated the prevalence of self‐reported musculoskeletal pain in young adults born across the range of preterm birth compared with a term‐born reference group. Methods: From two Finnish birth cohorts, 184 individuals born early preterm (<34 weeks), 350 late preterm (34 to <37 weeks) and 641 at term completed a self‐report questionnaire of musculoskeletal pain at mean age 24.1 (SD: 1.4) years. Group differences were examined by logistic regression models adjusting for sex, age and cohort (Model 1), potential early life confounders (Model 2) and lifestyle factors related to physical (Model 3) and mental health (Model 4). Results: The late preterm group had lower odds for reporting neck pain (0.73; 95% confidence interval (CI): 0.56–0.96), which was further reduced when adjusting for early life confounders and lifestyle factors (Model 4). Odds for reporting peripheral pain were 0.69 (95% CI: 0.48–0.99, Model 4) in the early preterm group. The odds for reporting any pain, shoulder, low back or widespread pain did not differ significantly between groups, although odds for reporting widespread pain were 0.77 (95% CI: 0.58–1.03, Model 4) in the late preterm group. Conclusions: We did not find evidence of increased prevalence of musculoskeletal pain in adults born early or late preterm. In contrast, our results suggest that adults born preterm have a slightly lower risk of reporting musculoskeletal pain, also when we adjusted for lifestyle factors. Significance: Young adults born preterm do not have increased rates of musculoskeletal pain. Our findings rather suggest that these rates may be slightly lower than among those born at term.

Significance Spatial patterns are a prominent and interesting feature of both biological and physical systems. We have discovered that mammalian mitotic chromosomes, which comprise two closely associated sister chromatids, exhibit two interesting spatial patterns. In one pattern, the structural axis of each chromatid acquires sequential partial helices of alternating handedness. In the other, an array of evenly spaced bridges links these two axes. Development of any spatial pattern requires communication within the system. We present a constellation of observations suggesting that these patterns are related and are promoted by a mechanical mechanism in which the communication required for development of patterns arises from redistribution of mechanical stress. Models involving bonded chromatin/axis bilayers and Kirchhoff–Love theory for elastic rods are discussed.

OBJECTIVE—To examine the relationship of obesity, measured as BMI, and weight change to incidence of coronary heart disease (CHD) among women with diabetes. RESEARCH DESIGN AND METHODS—We followed 5,897 women with type 2 diabetes in the Nurses’ Health Study for ≤20 years. Women were aged 40–74 years and had no history of cardiovascular disease or cancer at the beginning of the follow-up period. BMI values from three time points (age 18 years, year 1976, and current) were derived from the reported height (1976) and corresponding reported weight. Weight changes between age 18 years and 1976 and after diagnosis of diabetes were calculated. Women reported diagnoses of diabetes and CHD every 2 years. Incident CHD cases were confirmed by medical record review. RESULTS—During follow-up, we documented 418 incident cases of CHD (236 of nonfatal myocardial infarction and 182 of fatal CHD). After adjustment for age, smoking, and other coronary risk factors, current BMI was strongly associated with increased risk of CHD among diabetic women. The multivariate relative risks across increasing categories of BMI (&amp;lt;23.0, 23.0–24.9, 25.0–26.9, 27.0–29.9, 30.0–34.9, and ≥35.0 kg/m2) were 1.0, 1.58, 1.85, 1.95, 2.80, and 3.21, respectively (P for trend &amp;lt;0.001). Increasing BMI values from age 18 years to 1976, before diagnosis of diabetes, were also positively associated with risk of CHD. Weight gain before the diagnosis of diabetes was related to increased risk of CHD. In contrast, weight change after diagnosis of diabetes was not associated with risk of CHD. CONCLUSIONS—These findings provide strong evidence that obesity and weight gain before diagnosis of diabetes are associated with future risk of CHD among women with type 2 diabetes.

This paper demonstrates a new method for the synthesis of mixed self-assembled monolayers (mixed SAMs) by reaction of a reactive intermediatean interchain carboxylic anhydridewith alkylamines. The interchain anhydride was prepared in high yield from a SAM of 16-mercaptohexadecanoic acid (HS(CH2)15COOH) on gold by treatment with trifluoroacetic anhydride. Alkylamines reacted cleanly with the interchain anhydride to generate a mixed SAM, which comprised a mixture of acids and amides in approximately 1:1 ratio on the surface. The SAMs of the interchain anhydride and the mixed SAM were characterized using polarized infrared external reflectance spectroscopy, X-ray photoelectron spectroscopy, contact angle, and ellipsometry. Control of the wettability of the SAMs was demonstrated by allowing the interchain anhydride to react with alkylamines having different alkyl groups; this model system gave wetting data consistent with earlier studies of mixed monolayers and verified the ability of this method to manipulate interfacial physical properties. In certain circumstances, this method is experimentally simpler as a method to produce mixed SAMs than are conventional methods involving coadsorption of two thiols from a mixture in solution. It also assures two other characteristics of the mixed SAM: that the composition of the SAM is roughly 1:1 in carboxylic acid and amide groups, and that these two groups are well mixed on the surface.