Ralph B. D'Agostino

Bio: Ralph B. D'Agostino is an academic researcher from Wake Forest University. The author has contributed to research in topics: Framingham Heart Study & Framingham Risk Score. The author has an hindex of 226, co-authored 1287 publications receiving 229636 citations. Previous affiliations of Ralph B. D'Agostino include VA Boston Healthcare System & University of Illinois at Urbana–Champaign.

Diabetes in non-Hispanic white youth: prevalence, incidence, and clinical characteristics: the SEARCH for Diabetes in Youth Study.

Abstract: OBJECTIVE—To investigate the incidence, prevalence, and clinical characteristics of diabetes among U.S. non-Hispanic white (NHW) youth. RESEARCH DESIGN AND METHODS—Data from the SEARCH for Diabetes in Youth Study (SEARCH study), a multicenter study of diabetes among youth aged 0–19 years, were examined. Incidence rates were calculated per 100,000 person-years across 4 incident years (2002–2005), and prevalence in 2001 was calculated per 1,000 youths. Information obtained by questionnaire, physical examination, and blood and urine collection was analyzed to describe the characteristics of youth who completed an in-person visit. RESULTS—The prevalence of type 1 diabetes (at ages 0–19 years) was 2.00/1,000, which was similar for male (2.02/1,000) and female (1.97/1,000) subjects. The incidence of type 1 diabetes was 23.6/100,000, slightly higher for male compared with female subjects (24.5 vs. 22.7 per 100,000, respectively, P = 0.04). Incidence rates of type 1 diabetes among youth aged 0–14 years in the SEARCH study are higher than all previously reported U.S. studies and many European studies. Few cases of type 2 diabetes in youth aged 40% had elevated LDL cholesterol, and 10 years met current recommendations for intake of saturated fat. Among youth aged ≥15 years, 18% with type 1 and 26% with type 2 diabetes were current smokers. CONCLUSIONS—The SEARCH study is one of the most comprehensive studies of diabetes in NHW youth. The incidence of type 1 diabetes in NHW youth in the U.S. is one of the highest in the world. While type 2 diabetes is still relatively rare, rates are several-fold higher than those reported by European countries. We believe efforts directed at improving the cardiometabolic and behavioral risk factor profiles in this population are warranted.

Metabolic and Inflammation Variable Clusters and Prediction of Type 2 Diabetes: Factor Analysis Using Directly Measured Insulin Sensitivity

Abstract: Factor analysis, a multivariate correlation technique, has been used to provide insight into the underlying structure of the metabolic syndrome. The majority of previous factor analyses, however, have used only surrogate measures of insulin sensitivity; very few have included nontraditional cardiovascular disease (CVD) risk factors such as plasminogen activator inhibitor (PAI)-1, fibrinogen, and C-reactive protein (CRP); and only a limited number have assessed the ability of factors to predict type 2 diabetes. The objective of this study was to investigate, using factor analysis, the clustering of metabolic and inflammation variables using data from 1,087 nondiabetic participants in the Insulin Resistance Atherosclerosis Study (IRAS) and to determine the association of these clusters with risk of type 2 diabetes at follow-up. This study includes information on directly measured insulin sensitivity (S(i)) from the frequently sampled intravenous glucose tolerance test among African-American, Hispanic, and non-Hispanic white subjects aged 40-69 years. Principal factor analysis of data from nondiabetic subjects at baseline (1992-1994) identified three factors, which explained 28.4, 7.4, and 6% of the total variance in the dataset, respectively. Based on factor loadings of >or= 0.40, these factors were interpreted as 1) a "metabolic" factor, with positive loadings of BMI, waist circumference, 2-h glucose, log triglyceride, and log PAI-1 and inverse loadings of log S(i) + 1 and HDL; 2) an "inflammation" factor, with positive loadings of BMI, waist circumference, fibrinogen, and log CRP and an inverse loading of log S(i) + 1; and 3) a "blood pressure" factor, with positive loadings of systolic and diastolic blood pressure. The results were similar within strata of ethnicity, and there were only subtle differences in sex-specific analyses. In a prospective analysis, each of the factors was a significant predictor of diabetes after a median follow-up period of 5.2 years, and each factor remained significant in a multivariate model that included all three factors, although this three-factor model was not significantly more predictive than models using either impaired glucose tolerance or conventional CVD risk factors. Factor analysis identified three underlying factors among a group of inflammation and metabolic syndrome variables, with insulin sensitivity loading on both the metabolic and inflammation variable clusters. Each factor significantly predicted diabetes in multivariate analysis. The findings support the emerging hypothesis that chronic subclinical inflammation is associated with insulin resistance and comprises a component of the metabolic syndrome.

Loss of XIST in Breast Cancer Activates MSN-c-Met and Reprograms Microglia via Exosomal miRNA to Promote Brain Metastasis

Abstract: Up to 30% of patients with metastatic breast cancer eventually develop brain metastasis, yet the pathologic mechanism behind this development remains poorly understood. Here, we profiled long noncoding RNAs in brain metastatic tumors from patients with breast cancer and found that the X-inactive-specific transcript (XIST) was significantly downregulated in these tissues. XIST expression levels inversely correlated with brain metastasis, but not with bone metastasis in patients. Silencing of XIST preferentially promoted brain metastatic growth of XISThigh cells in our xenograft models. Moreover, knockout of XIST in mice mammary glands accelerated primary tumor growth as well as metastases in the brain. Decreased expression of XIST stimulated epithelial-mesenchymal transition and activated c-Met via MSN-mediated protein stabilization, which resulted in the promotion of stemness in the tumor cells. Loss of XIST also augmented secretion of exosomal miRNA-503, which triggered M1-M2 polarization of microglia. This M1-M2 conversion upregulated immune suppressive cytokines in microglia that suppressed T-cell proliferation. Furthermore, we screened an FDA-approved drug library and identified fludarabine as a synthetic lethal drug for XISTlow breast tumor cells and found that fludarabine blocked brain metastasis in our animal model. Our results indicate that XIST plays a critical role in brain metastasis in breast cancer by affecting both tumor cells and the tumor microenvironment and that the XIST-mediated pathway may serve as an effective target for treating brain metastasis.Significance: These findings describe mechanisms of how loss of the lncRNA XIST promotes brain metastasis in breast cancer and identify fludarabine as a potential therapeutic agent that specifically eliminates XISTlow tumor cells in the brain. Cancer Res; 78(15); 4316-30. ©2018 AACR.

The Appropriateness of Some Common Procedures for Testing the Equality of Two Independent Binomial Populations

Abstract: For testing the equality of two independent binomial populations the Fisher exact test and the chi-squared test with Yates's continuity correction are often suggested for small and intermediate size samples. The use of these tests is inappropriate in that they are extremely conservative. In this article we demonstrate that, even for small samples, the uncorrected chi-squared test (i.e., the Pearson chi-squared test) and the two-independent-sample t test are robust in that their actual significance levels are usually close to or smaller than the nominal levels. We encourage the use of these latter two tests.

Maximum likelihood estimation for interval-censored data using a Weibull-based accelerated failure time model

Abstract: The accelerated failure time regression model is most commonly used with right-censored survival data. This report studies the use of a Weibull-based accelerated failure time regression model when left- and interval-censored data are also observed. Two alternative methods of analysis are considered. First, the maximum likelihood estimates (MLEs) for the observed censoring pattern are computed. These are compared with estimates where midpoints are substituted for left- and interval-censored data (midpoint estimator, or MDE). Simulation studies indicate that for relatively large samples there are many instances when the MLE is superior to the MDE. For samples where the hazard rate is flat or nearly so, or where the percentage of interval-censored data is small, the MDE is adequate. An example using Framingham Heart Study data is discussed.

G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences

Abstract: G*Power (Erdfelder, Faul, & Buchner, 1996) was designed as a general stand-alone power analysis program for statistical tests commonly used in social and behavioral research. G*Power 3 is a major extension of, and improvement over, the previous versions. It runs on widely used computer platforms (i.e., Windows XP, Windows Vista, and Mac OS X 10.4) and covers many different statistical tests of thet, F, and χ2 test families. In addition, it includes power analyses forz tests and some exact tests. G*Power 3 provides improved effect size calculators and graphic options, supports both distribution-based and design-based input modes, and offers all types of power analyses in which users might be interested. Like its predecessors, G*Power 3 is free.

The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 report.

Abstract: "The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure" provides a new guideline for hypertension prevention and management. The following are the key messages(1) In persons older than 50 years, systolic blood pressure (BP) of more than 140 mm Hg is a much more important cardiovascular disease (CVD) risk factor than diastolic BP; (2) The risk of CVD, beginning at 115/75 mm Hg, doubles with each increment of 20/10 mm Hg; individuals who are normotensive at 55 years of age have a 90% lifetime risk for developing hypertension; (3) Individuals with a systolic BP of 120 to 139 mm Hg or a diastolic BP of 80 to 89 mm Hg should be considered as prehypertensive and require health-promoting lifestyle modifications to prevent CVD; (4) Thiazide-type diuretics should be used in drug treatment for most patients with uncomplicated hypertension, either alone or combined with drugs from other classes. Certain high-risk conditions are compelling indications for the initial use of other antihypertensive drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, β-blockers, calcium channel blockers); (5) Most patients with hypertension will require 2 or more antihypertensive medications to achieve goal BP (<140/90 mm Hg, or <130/80 mm Hg for patients with diabetes or chronic kidney disease); (6) If BP is more than 20/10 mm Hg above goal BP, consideration should be given to initiating therapy with 2 agents, 1 of which usually should be a thiazide-type diuretic; and (7) The most effective therapy prescribed by the most careful clinician will control hypertension only if patients are motivated. Motivation improves when patients have positive experiences with and trust in the clinician. Empathy builds trust and is a potent motivator. Finally, in presenting these guidelines, the committee recognizes that the responsible physician's judgment remains paramount.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure

Abstract: The National High Blood Pressure Education Program presents the complete Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Like its predecessors, the purpose is to provide an evidence-based approach to the prevention and management of hypertension. The key messages of this report are these: in those older than age 50, systolic blood pressure (BP) of greater than 140 mm Hg is a more important cardiovascular disease (CVD) risk factor than diastolic BP; beginning at 115/75 mm Hg, CVD risk doubles for each increment of 20/10 mm Hg; those who are normotensive at 55 years of age will have a 90% lifetime risk of developing hypertension; prehypertensive individuals (systolic BP 120-139 mm Hg or diastolic BP 80-89 mm Hg) require health-promoting lifestyle modifications to prevent the progressive rise in blood pressure and CVD; for uncomplicated hypertension, thiazide diuretic should be used in drug treatment for most, either alone or combined with drugs from other classes; this report delineates specific high-risk conditions that are compelling indications for the use of other antihypertensive drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, calcium channel blockers); two or more antihypertensive medications will be required to achieve goal BP (<140/90 mm Hg, or <130/80 mm Hg) for patients with diabetes and chronic kidney disease; for patients whose BP is more than 20 mm Hg above the systolic BP goal or more than 10 mm Hg above the diastolic BP goal, initiation of therapy using two agents, one of which usually will be a thiazide diuretic, should be considered; regardless of therapy or care, hypertension will be controlled only if patients are motivated to stay on their treatment plan. Positive experiences, trust in the clinician, and empathy improve patient motivation and satisfaction. This report serves as a guide, and the committee continues to recognize that the responsible physician's judgment remains paramount.