618 research outputs found

    Common and specific impairments in attention functioning in girls with chromosome 22q11.2 deletion, fragile X or Turner syndromes.

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    BACKGROUND: Chromosome 22q11.2 deletion syndrome (22q11.2DS), fragile X syndrome (FXS), and Turner syndrome (TS) are complex and variable developmental syndromes caused by different genetic abnormalities; yet, they share similar cognitive impairments in the domains of numbers, space, and time. The atypical development of foundational neural networks that underpin the attentional system is thought to result in further impairments in higher-order cognitive functions. The current study investigates whether children with similar higher-order cognitive impairments but different genetic disorders also show similar impairments in alerting, orienting, and executive control of attention. METHODS: Girls with 22q11.2DS, FXS, or TS and typically developing (TD) girls, aged 7 to 15 years, completed an attention network test, a flanker task with alerting and orienting cues. Exploration of reaction times and accuracy allowed us to test for potential commonalities in attentional functioning in alerting, orienting, and executive control. Linear regression models were used to test whether the predictors of group and chronological age were able to predict differences in attention indices. RESULTS: Girls with 22q11.2DS, FXS, or TS demonstrated unimpaired function of the alerting system and impaired function of the executive control system. Diagnosis-specific impairments were found such that girls with FXS made more errors and had a reduced orienting index, while girls with 22q11.2DS showed specific age-related deficits in the executive control system. CONCLUSIONS: These results suggest that the control but not the implementation of attention is selectively impaired in girls with 22q11.2DS, TS or FXS. Additionally, the age effect on executive control in girls with 22q11.2DS implies a possible altered developmental trajectory

    Influence of the X-chromosome on neuroanatomy: evidence from Turner and Klinefelter syndromes.

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    Studies of sex effects on neurodevelopment have traditionally focused on animal models investigating hormonal influences on brain anatomy. However, more recent evidence suggests that sex chromosomes may also have direct upstream effects that act independently of hormones. Sex chromosome aneuploidies provide ideal models to examine this framework in humans, including Turner syndrome (TS), where females are missing one X-chromosome (45X), and Klinefelter syndrome (KS), where males have an additional X-chromosome (47XXY). As these disorders essentially represent copy number variants of the sex chromosomes, investigation of brain structure across these disorders allows us to determine whether sex chromosome gene dosage effects exist. We used voxel-based morphometry to investigate this hypothesis in a large sample of children in early puberty, to compare regional gray matter volumes among individuals with one (45X), two (typically developing 46XX females and 46XY males), and three (47XXY) sex chromosomes. Between-group contrasts of TS and KS groups relative to respective sex-matched controls demonstrated highly convergent patterns of volumetric differences with the presence of an additional sex chromosome being associated with relatively decreased parieto-occipital gray matter volume and relatively increased temporo-insular gray matter volumes. Furthermore, z-score map comparisons between TS and KS cohorts also suggested that this effect occurs in a linear dose-dependent fashion. We infer that sex chromosome gene expression directly influences brain structure in children during early stages of puberty, extending our understanding of genotype-phenotype mechanisms underlying sex differences in the brain

    A Turner syndrome neurocognitive phenotype maps to Xp22.3

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    BACKGROUND: Turner syndrome (TS) is associated with a neurocognitive phenotype that includes selective nonverbal deficits, e.g., impaired visual-spatial abilities. We previously reported evidence that this phenotype results from haploinsufficiency of one or more genes on distal Xp. This inference was based on genotype/phenotype comparisons of individual girls and women with partial Xp deletions, with the neurocognitive phenotype considered a dichotomous trait. We sought to confirm our findings in a large cohort (n = 47) of adult women with partial deletions of Xp or Xq, enriched for subjects with distal Xp deletions. METHODS: Subjects were recruited from North American genetics and endocrinology clinics. Phenotype assessment included measures of stature, ovarian function, and detailed neurocognitive testing. The neurocognitive phenotype was measured as a quantitative trait, the Turner Syndrome Cognitive Summary (TSCS) score, derived from discriminant function analysis. Genetic analysis included karyotyping, X inactivation studies, fluorescent in situ hybridization, microsatellite marker genotyping, and array comparative genomic hybridization. RESULTS: We report statistical evidence that deletion of Xp22.3, an interval containing 31 annotated genes, is sufficient to cause the neurocognitive phenotype described by the TSCS score. Two other cardinal TS features, ovarian failure and short stature, as well as X chromosome inactivation pattern and subject\u27s age, were unrelated to the TSCS score. CONCLUSION: Detailed mapping suggests that haploinsufficiency of one or more genes in Xp22.3, the distal 8.3 megabases (Mb) of the X chromosome, is responsible for a TS neurocognitive phenotype. This interval includes the 2.6 Mb Xp-Yp pseudoautosomal region (PAR1). Haploinsufficiency of the short stature gene SHOX in PAR1 probably does not cause this TS neurocognitive phenotype. Two genes proximal to PAR1 within the 8.3 Mb critical region, STS and NLGN4X, are attractive candidates for this neurocognitive phenotype

    Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high-risk, early breast cancer

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    Adjuvant therapy; Breast cancer; OlaparibTerapia adyuvante; Cáncer de mama; OlaparibTeràpia adjuvant; Càncer de mama; OlaparibBackground The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety. Patients and methods One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015. Results With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Δ 3.4%, 95% CI −0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Δ 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Δ 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome. Conclusion With 3.5 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDFS and DDFS with no new safety signals.Funding for this work, which was conducted as a collaborative partnership among the Breast International Group, NRG Oncology, Frontier Science, AstraZeneca, and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, U.S.A. (MSD), was provided by the National Institutes of Health (grant numbers: U10CA 180868, UG1CA 189867, and U10CA 180822) and by AstraZeneca as part of an alliance between AstraZeneca and MSD. Provision of olaparib and placebo was from AstraZeneca

    Evaluation of the American-English Quality of Life in Short Stature Youth (QoLISSY) questionnaire in the United States.

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    BACKGROUND: The European Quality of Life in Short Stature Youth (QoLISSY) is a novel condition-specific instrument developed to assess health related quality of life (HrQoL) in children/adolescents with short stature from patient and parent perspectives. Study objective was to linguistically validate and psychometrically test the American-English version of the QoLISSY instrument. METHODS: Upon conversion of the British-English version to American-English, content validity and acceptance of the questionnaire were examined through focus group discussions with cognitive debriefing in 28 children/adolescents with growth hormone deficiency (GHD) or idiopathic short stature (ISS) and their parents. In the subsequent field test with 51 families and a re-test with 25 families the psychometric performance of the American-English version was examined and compared with the original European dataset. RESULTS: Pilot test results supported the suitability of the American-English version. Good internal consistency with Cronbach\u27s Alpha ranging from 0.84 to 0.97 and high test-re-test reliabilities were observed in the field test. The QoLISSY was able to detect significant differences according to the degree of short stature with higher HrQoL for taller children. Correlations with a generic HrQoL tool support the QoLISSY\u27s concurrent validity. The scale\u27s operating characteristics were comparable to the original European data. CONCLUSION: Results support that the QoLISSY American-English version is a psychometrically sound short stature-specific instrument to assess the patient- and parent- perceived impact of short stature. The QoLISSY instrument is fit for use in clinical studies and health services research in the American-English speaking population

    Proteomic risk markers for coronary heart disease and stroke: validation and mediation of randomized trial hormone therapy effects on these diseases

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    Background: We previously reported mass spectrometry-based proteomic discovery research to identify novel plasma proteins related to the risk of coronary heart disease (CHD) and stroke, and to identify proteins with concentrations affected by the use of postmenopausal hormone therapy. Here we report CHD and stroke risk validation studies for highly ranked proteins, and consider the extent to which protein concentration changes relate to disease risk or provide an explanation for hormone therapy effects on these outcomes. Methods: Five proteins potentially associated with CHD (beta-2 microglobulin (B2M), alpha-1-acid glycoprotein 1 (ORM1), thrombospondin-1(THBS1), complement factor D pre-protein (CFD), and insulin-like growth factor binding protein 1 (IGFBP1)) and five potentially associated with stroke (B2M, IGFBP2, IGFBP4, IGFBP6, and hemopexin (HPX)) had high discovery phase significance level ranking and an available ELISA assay, and were included in case-control validation studies within the Women’s Health Initiative (WHI) hormone therapy trials. Protein concentrations, at baseline and 1 year following randomization, were assessed for 358 CHD cases and 362 stroke cases, along with corresponding disease-free controls. Disease association, and mediation of estrogen-alone and estrogen plus progestin effects on CHD and stroke risk, were assessed using logistic regression. Results: B2M, THBS1, and CFD were confirmed (P <0.05) as novel CHD risk markers, and B2M, IGFBP2, and IGFBP4 were confirmed as novel stroke disease risk markers, while the assay for HPX proved to be unreliable. The change from baseline to 1 year in B2M was associated (P <0.05) with subsequent stroke risk, and trended similarly with subsequent CHD risk. Change from baseline to 1 year in IGFBP1 was also associated with CHD risk, and this change provided evidence of hormone therapy effect mediation. Conclusions: Plasma B2M is confirmed to be an informative risk marker for both CHD and stroke. The B2M increase experienced by women during the first year of hormone therapy trial participation conveys cardiovascular disease risk. The increase in IGFBP1 similarly conveys CHD risk, and the magnitude of the IGFBP1 increase following hormone therapy may be a mediator of hormone therapy effects. Plasma THBS1 and CFD are confirmed as CHD risk markers, and plasma IGFBP4 and IGFBP2 are confirmed as stroke risk markers. Clinical trials registration ClinicalTrials.gov identifier: NCT0000061

    FHL2 inhibits the activated osteoclast in a TRAF6-dependent manner

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    TNF receptor–associated factor 6 (TRAF6) associates with the cytoplasmic domain of receptor activator of NF-κB (RANK). This event is central to normal osteoclastogenesis. We discovered that TRAF6 also interacts with FHL2 (four and a half LIM domain 2), a LIM domain–only protein that functions as a transcriptional coactivator or corepressor in a cell-type–specific manner. FHL2 mRNA and protein are undetectable in marrow macrophages and increase pari passu with osteoclast differentiation in vitro. FHL2 inhibits TRAF6-induced NF-κB activity in wild-type osteoclast precursors and, in keeping with its role as a suppressor of TRAF6-mediated RANK signaling, TRAF6/RANK association is enhanced in FHL2(–/–) osteoclasts. FHL2 overexpression delays RANK ligand–induced (RANKL-induced) osteoclast formation and cytoskeletal organization. Interestingly, osteoclast-residing FHL2 is not detectable in naive wild-type mice, in vivo, but is abundant in those treated with RANKL and following induction of inflammatory arthritis. Reflecting increased RANKL sensitivity, osteoclasts generated from FHL2(–/–) mice reach maturation and optimally organize their cytoskeleton earlier than their wild-type counterparts. As a consequence, FHL2(–/–) osteoclasts are hyperresorptive, and mice lacking the protein undergo enhanced RANKL and inflammatory arthritis–stimulated bone loss. FHL2 is, therefore, an antiosteoclastogenic molecule exerting its effect by attenuating TRAF6-mediated RANK signaling

    Generation of three different fragments of bound C3 with purified factor I or serum. II. Location of binding sites in the C3 Fragments for Factors B and H, complement receptors , and bovine conglutinin

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    The many different recognized functions of C3 are dependent upon the ability of the activated C3 molecule both to bind covalently to protein and carbohydrate surfaces and to provide binding sites for as many as eleven different proteins. The location of the binding sites for six of these different proteins (factors B and H, complement receptors CR(1), CR(2) and CR(3) and conglutinin) was examined in the naturally occurring C3-fragments generated by C3 activation (C3b) and degradation by Factor I (iC3b, C3c, C3d,g) and trypsin (C3d). Evidence was obtained for at least four distinct binding sites in C3 for these six different C3 ligands. One binding site for B was detectable only in C3b, whereas a second binding site for H and CR(1) was detectable in both C3b and iC3b. The affinity of the binding site for H and CR(1) was charge dependent and considerably reduced in iC3b as compared to C3b. H binding to iC3b-coated sheep erythrocytes (EC3bi) was measurable only in low ionic strength buffer (4 mS). The finding that C3c-coated microspheres bound to CR(1), indicated that this second binding site was still intact in the C3c fragment. However, H binding to C3c was not examined. A third binding site in C3 for CR(2) was exposed in the d region by factor I cleavage of C3b into iC3b, and the activity of this site was unaffected by the further I cleavage of iC3b into C3d,g. Removal of the 8,000-dalton C3g fragment from C3d,g with trypsin forming C3d, resulted in reduced CR2 activity. However, because saturating amounts of monoclonal anti-C3g did not block the CR(2)-binding activity of EC3d,g, it appears unlikely that the g region of C3d,g or iC3b forms a part of the CR(2)-binding site. In addition, detergent-solubilized EC3d (C3d-OR) inhibited the CR(2)-binding activity of EC3d,g. Monocytes and neutrophils, that had been previously thought to lack CR(2) because of their inability to form EC3d rosettes, did bind EC3d,g containing greater than 5 × 10(4) C3d,g molecules per E. The finding that monocyte and neutrophil rosettes with EC3d,g were inhibited by C3d-OR, suggested that these phagocytic cells might indeed express very low numbers of CR(2), and that these CR(2) were detectable with EC3d,g and not with EC3d because C3d,g had a higher affinity for CR2 than did C3d. A fourth C3 binding site for CR(3) and conglutinin (K) was restricted to the iC3b fragment. Because of simultaneous attachment of iC3b to phagocyte CR3 and CR(3), the characteristics of iC3b binding to CR3 could only be examined with phagocytes on which the CR(1) had been blocked with anti-CR(1). Inhibition studies with EDTA and N-acetyl-D-glucosamine demonstrated a requirement for both calcium cations and carbohydrate in the binding of EC3bi to CR3 and to K. However, CR(3) differed from K in that magnesium cations were required in addition to calcium for maximum CR(3) binding activity, and NADG produced less inhibition of CR(3) activity than of K activity
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