171 research outputs found
Induction of Activity-Regulated Cytoskeleton-Associated Protein and c-Fos Expression in an Animal Model of Anorexia Nervosa
Anorexia nervosa (AN) is a complex eating disorder characterized by reduced caloric intake to achieve body-weight loss. Furthermore, over-exercise is commonly reported. In recent years, animal models of AN have provided evidence for neuroplasticity changes in specific brain areas of the mesocorticolimbic circuit, which controls a multitude of functions including reward, emotion, motivation, and cognition. The activity-regulated cytoskeleton-associated protein (Arc) is an immediate early gene that modulates several forms of synaptic plasticity and has been linked to neuropsychiatric illness. Since the role of Arc in AN has never been investigated, in this study we evaluated whether the anorexic-like phenotype reproduced by the activity-based anorexia (ABA) model may impact its expression in selected brain regions that belong to the mesocorticolimbic circuit (i.e., prefrontal cortex, nucleus accumbens, and hippocampus). The marker of neuronal activation c-Fos was also assessed. We found that the expression of both markers increased in all the analyzed brain areas of ABA rats in comparison to the control groups. Moreover, a negative correlation between the density of Arc-positive cells and body-weight loss was found. Together, our findings suggest the importance of Arc and neuroplasticity changes within the brain circuits involved in dysfunctional behaviors associated with AN
Protocol for the Northern Manhattan Diabetes Community Outreach Project. A randomised trial of a community health worker intervention to improve diabetes care in Hispanic adults
ObjectiveHispanics in the USA are affected by the diabetes epidemic disproportionately, and they consistently have lower access to care, poorer control of the disease and higher risk of complications. This study evaluates whether a community health worker (CHW) intervention may improve clinically relevant markers of diabetes care in adult underserved Hispanics.Methods and analysisThe Northern Manhattan Diabetes Community Outreach Project (NOCHOP) is a two-armed randomised controlled trial to be performed as a community-based participatory research study performed in a Primary Care Setting in Northern Manhattan (New York City). 360 Hispanic adults with poorly controlled type 2 diabetes mellitus (haemoglobin A1c >8%), aged 35–70 years, will be randomised at a 1:1 ratio, within Primary Care Provider clusters. The two study arms are (1) a 12-month CHW intervention and (2) enhanced usual care (educational materials mailed at 4-month intervals, preceded by phone calls). The end points, assessed after 12 months, are primary = haemoglobin A1c and secondary = blood pressure and low-density lipoprotein-cholesterol levels. In addition, the study will describe the CHW intervention in terms of components and intensity and will assess its effects on (1) medication adherence, (2) medication intensification, (3) diet and (4) physical activity.Ethics and disseminationAll participants will provide informed consent; the study protocol has been approved by the Institutional Review Board of Columbia University Medical Center. CHW interventions hold great promise in improving the well-being of minority populations who suffer from diabetes mellitus. The NOCHOP study will provide valuable information about the efficacy of those interventions vis-à-vis clinically relevant end points and will inform policy makers through a detailed characterisation of the programme and its effects.Clinical trial registration numberNCT00787475 at clinicaltrials.gov
Mild Cognitive Dysfunction Does Not Affect Diabetes Mellitus Control in Minority Elderly Adults
To determine whether older adults with type 2 diabetes mellitus and cognitive dysfunction have poorer metabolic control of glycosylated hemoglobin, systolic blood pressure, and low-density lipoprotein cholesterol than those without cognitive dysfunction
Depression is not associated with diabetes control in minority elderly
We investigated the longitudinal association of depression, with and without cognitive dysfunction, with hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and low-density lipoprotein (LDL) in a predominantly minority cohort
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Polysomy and p16 deletion by fluorescence in situ hybridization in the diagnosis of indeterminate biliary strictures
Background: The diagnosis of indeterminate biliary strictures is limited because of the low sensitivity of cytology. However, an accurate diagnosis of malignancy is critical in the management of patients with suspected biliary malignancy. Testing for chromosomal aneuploidy by fluorescence in situ hybridization (FISH) may increase the yield.
Objective: To evaluate the diagnostic accuracy of FISH in indeterminate biliary strictures and the additional value of including deletion of 9p21 (p16) in the diagnostic criteria of malignant biliary strictures.
Design: Retrospective review.
Setting: Academic medical center.
Patients: This study involved 76 consecutive patients who were seen for the evaluation of indeterminate strictures at our institution. These patients were screened, and 50 patients with either a final pathologic diagnosis or ≥ 12 months' conclusive follow-up were included in the analysis.
Main outcome measurements: Sensitivity, specificity, and area under the curve (AUC) analysis of cytology alone compared with the presence of FISH polysomy versus FISH polysomy and 9p21 deletion.
Results: The presence of increased copy numbers (polysomy) of chromosome 3, 7, or 17 by FISH increased the sensitivity of brush cytology from 21% to 58%, and when the presence of 9p21 deletion was included, the sensitivity increased to 89%. The specificity of FISH was 97% (vs 100% for cytology). The accuracy of cytology combined with FISH polysomy (AUC = 0.93) or p16 deletion was significantly greater than the accuracy of cytology alone (AUC 0.6; P < .001) or even cytology combined with FISH polysomy (AUC = 0.77; P ≤ .05).
Limitations: Sample size. There is a relatively high incidence of malignant biliary strictures in the entire cohort but low incidence among primary sclerosing cholangitis patients, and the majority of cancers are cholangiocarcinomas (as opposed to pancreatic).
Conclusion: FISH significantly improves the diagnostic accuracy of brush cytology in indeterminate biliary strictures. In our series, the addition of 9p21 deletion to FISH polysomy and cytology further improved sensitivity. This suggests that 9p21 deletion may be added to the diagnostic criteria in indeterminate strictures
Genetic association analysis highlights new loci that modulate hematological trait variation in Caucasians and African Americans
Red blood cell, white blood cell, and platelet measures, including their count, sub-type and volume, are important diagnostic and prognostic clinical parameters for several human diseases. To identify novel loci associated with hematological traits, and compare the architecture of these phenotypes between ethnic groups, the CARe Project genotyped 49,094 single nucleotide polymorphisms (SNPs) that capture variation in ~2,100 candidate genes in DNA of 23,439 Caucasians and 7,112 African Americans from five population-based cohorts. We found strong novel associations between erythrocyte phenotypes and the glucose-6 phosphate dehydrogenase (G6PD) A-allele in African Americans (rs1050828, P < 2.0 × 10−13, T-allele associated with lower red blood cell count, hemoglobin, and hematocrit, and higher mean corpuscular volume), and between platelet count and a SNP at the tropomyosin-4 (TPM4) locus (rs8109288, P = 3.0 × 10−7 in Caucasians; P = 3.0 × 10−7 in African Americans, T-allele associated with lower platelet count). We strongly replicated many genetic associations to blood cell phenotypes previously established in Caucasians. A common variant of the α-globin (HBA2-HBA1) locus was associated with red blood cell traits in African Americans, but not in Caucasians (rs1211375, P < 7 × 10−8, A-allele associated with lower hemoglobin, mean corpuscular hemoglobin, and mean corpuscular volume). Our results show similarities but also differences in the genetic regulation of hematological traits in European- and African-derived populations, and highlight the role of natural selection in shaping these differences
Population Structure of Hispanics in the United States: The Multi-Ethnic Study of Atherosclerosis
Using ∼60,000 SNPs selected for minimal linkage disequilibrium, we perform population structure analysis of 1,374 unrelated Hispanic individuals from the Multi-Ethnic Study of Atherosclerosis (MESA), with self-identification corresponding to Central America (n = 93), Cuba (n = 50), the Dominican Republic (n = 203), Mexico (n = 708), Puerto Rico (n = 192), and South America (n = 111). By projection of principal components (PCs) of ancestry to samples from the HapMap phase III and the Human Genome Diversity Panel (HGDP), we show the first two PCs quantify the Caucasian, African, and Native American origins, while the third and fourth PCs bring out an axis that aligns with known South-to-North geographic location of HGDP Native American samples and further separates MESA Mexican versus Central/South American samples along the same axis. Using k-means clustering computed from the first four PCs, we define four subgroups of the MESA Hispanic cohort that show close agreement with self-identification, labeling the clusters as primarily Dominican/Cuban, Mexican, Central/South American, and Puerto Rican. To demonstrate our recommendations for genetic analysis in the MESA Hispanic cohort, we present pooled and stratified association analysis of triglycerides for selected SNPs in the LPL and TRIB1 gene regions, previously reported in GWAS of triglycerides in Caucasians but as yet unconfirmed in Hispanic populations. We report statistically significant evidence for genetic association in both genes, and we further demonstrate the importance of considering population substructure and genetic heterogeneity in genetic association studies performed in the United States Hispanic population
Combined admixture mapping and association analysis identifies a novel blood pressure genetic locus on 5p13: contributions from the CARe consortium
Admixture mapping based on recently admixed populations is a powerful method to detect disease variants with substantial allele frequency differences in ancestral populations. We performed admixture mapping analysis for systolic blood pressure (SBP) and diastolic blood pressure (DBP), followed by trait-marker association analysis, in 6303 unrelated African-American participants of the Candidate Gene Association Resource (CARe) consortium. We identified five genomic regions (P< 0.001) harboring genetic variants contributing to inter-individual BP variation. In follow-up association analyses, correcting for all tests performed in this study, three loci were significantly associated with SBP and one significantly associated with DBP (P< 10−5). Further analyses suggested that six independent single-nucleotide polymorphisms (SNPs) contributed to the phenotypic variation observed in the admixture mapping analysis. These six SNPs were examined for replication in multiple, large, independent studies of African-Americans [Women's Health Initiative (WHI), Maywood, Genetic Epidemiology Network of Arteriopathy (GENOA) and Howard University Family Study (HUFS)] as well as one native African sample (Nigerian study), with a total replication sample size of 11 882. Meta-analysis of the replication set identified a novel variant (rs7726475) on chromosome 5 between the SUB1 and NPR3 genes, as being associated with SBP and DBP (P< 0.0015 for both); in meta-analyses combining the CARe samples with the replication data, we observed P-values of 4.45 × 10−7 for SBP and 7.52 × 10−7 for DBP for rs7726475 that were significant after accounting for all the tests performed. Our study highlights that admixture mapping analysis can help identify genetic variants missed by genome-wide association studies because of drastically reduced number of tests in the whole genome
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Genome-Wide Association of Body Fat Distribution in African Ancestry Populations Suggests New Loci
Central obesity, measured by waist circumference (WC) or waist-hip ratio (WHR), is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS) of fat distribution among those of predominantly African ancestry (AA). We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in AA individuals using meta-analyses of GWA results for WC and WHR (stage 1). Overall, 25 SNPs with single genomic control (GC)-corrected p-values<5.0×10−6 were followed-up (stage 2) in AA with WC and with WHR. Additionally, we interrogated genomic regions of previously identified European ancestry (EA) WHR loci among AA. In joint analysis of association results including both Stage 1 and 2 cohorts, 2 SNPs demonstrated association, rs2075064 at LHX2, p = 2.24×10−8 for WC-adjusted-for-BMI, and rs6931262 at RREB1, p = 2.48×10−8 for WHR-adjusted-for-BMI. However, neither signal was genome-wide significant after double GC-correction (LHX2: p = 6.5×10−8; RREB1: p = 5.7×10−8). Six of fourteen previously reported loci for waist in EA populations were significant (p<0.05 divided by the number of independent SNPs within the region) in AA studied here (TBX15-WARS2, GRB14, ADAMTS9, LY86, RSPO3, ITPR2-SSPN). Further, we observed associations with metabolic traits: rs13389219 at GRB14 associated with HDL-cholesterol, triglycerides, and fasting insulin, and rs13060013 at ADAMTS9 with HDL-cholesterol and fasting insulin. Finally, we observed nominal evidence for sexual dimorphism, with stronger results in AA women at the GRB14 locus (p for interaction = 0.02). In conclusion, we identified two suggestive loci associated with fat distribution in AA populations in addition to confirming 6 loci previously identified in populations of EA. These findings reinforce the concept that there are fat distribution loci that are independent of generalized adiposity
Admixture Mapping of Coronary Artery Calcified Plaque in African Americans With Type 2 Diabetes Mellitus
The presence and severity of coronary artery calcified plaque (CAC) differs markedly between individuals of African and European descent, suggesting that admixture mapping (AM) may be informative for identifying genetic variants associated with subclinical cardiovascular disease (CVD)
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