Citations

Introduction: Estrogens have been associated with risk of stroke in both men and women. Estradiol and estrone are synthesized from testosterone via the aromatase enzyme in both men and postmenopausal women. Genetic variation affecting function of the aromatase gene (CYP19A1) has been linked to elevated estradiol levels. We tested the hypothesis that these variants, as well as a modifying gene, are associated with ischemic stroke in three cohorts: the Vitamin Intervention for Stroke Prevention trial (VISP), Women’s Health Initiative (WHI), and Genetic Susceptibility to Early-Onset Stroke study (GEOS). Methods: Genomic data for individuals of European descent with ischemic stroke was compared against an equal number of controls: VISP (1723 cases - 65% men), WHI (436 cases - all postmenopausal women), GEOS (557 cases - all men age <55). Genotyping was funded through the Genomics and Randomized Trials Network (GARNET) and Gene Environment Association Studies (GENEVA) consortia. All cohorts used the Illumina Omni1-Quad chip for genotyping with imputation as needed. Eight candidate single nucleotide polymorphisms (SNPs) in CYP19A1 on chromosome 15 and an additional regulatory SNP in a modifier locus on chromosome 8 were chosen for analysis due to coding status or previous association with estradiol levels. Analyses were adjusted for age, hormone therapy use (women), and the top three principal components. Association results were determined as odds ratios for individual SNPs (effect allele = minor), with significance level of p<0.05. Results: GWAS results are tabulated. There were no significant differences in allele frequency for four SNPs in CYP19A1 among stroke patients and controls. The additional four SNPs were monomorphic in all three populations. The modifier gene SNP (rs1864729) was less common among young men with prior stroke in GEOS, but not men in VISP or in women. Conclusions: Aromatase genetic variation was not associated with risk of stroke in these three cohorts. One SNP that modifies aromatase function was less common among young, but not older men with stroke. Replication in other studies is necessary.

BACKGROUND: Recent genome-wide association studies (GWAS) have identified a number of novel SNPs associated with blood pressure and hypertension-related traits although studies were very large (approaching 80K participants) and effect sizes were modest with per allele effect sizes as small variants as a single millimeter of mercury difference in blood pressure. However, because hypertension is the most potent modifiable risk factor for ischemic stroke, lowering blood pressure by a few mm Hg can translate into measurable decrease in stroke risk. METHODS: We investigated 22 hypertension (HTN) associated SNPs in a case-control analysis of ischemic stroke in multiple stroke studies including the Siblings With Ischemic Stroke Study (SWISS), the Ischemic Stroke Genetics Study (ISGS), the Bio-Repository of DNA in Stroke (BRAINS), the Vitamin Intervention for Stroke Prevention (VISP) trial, and the Women's Health Initiative (WHI). SWISS/ISGS/BRAINS were analyzed together and included subtype information. Genotyping was funded through the individual studies, the Genomics and Randomized Trials Network (GARNET) consortium, and the SHARe (SNP Health Association Resource). All studies had both raw and imputed GWAS data. Analyses included the following phenotypes: all ischemic stroke, stroke subtypes, and age-at-stroke-onset and were stratified by race. Analyses were minimally adjusted for age, sex and principal components 1 & 2. Alpha was set at 0.05. RESULTS: Eleven of the SNPs from the HTN GWAS were associated with ischemic stroke in European ancestry from one or more of the study populations. Two SNPs on chromosome 12 and one on chromosome 21 were associated in multiple European ancestry cohorts. No SNP was associated in all studies. A SNP previously associated with HTN in African ancestry populations was associated with stroke in African-Americans. Analysis of subtypes found associations with small vessel disease and cardioembolic stroke but not large artery disease. The case-only age-at-stroke-onset analysis also found associations for the two SNPs on chromosome 12. CONCLUSION: These data suggest that candidate SNPs from a HTN GWAS may be associated with ischemic stroke and warrant further investigation. Racial differences were observed. Replication in populations from the other SiGN (Stroke Genetics Network), GENEVA (Gene Environment Association Studies) consortium, and the ISGC (International Stroke Genetics Consortium) studies are underway.

Introduction: The metabolic syndrome (MetS) leads to cardiac vascular injury, which may reflect in increased retention of endothelial progenitor cells (EPC). Coronary endothelial cell (EC) mitochondria partly regulate vascular function and structure. We hypothesized that chronic mitoprotection would preserve EC mitochondria and attenuate coronary vascular injury and dysfunction in swine MetS. Methods: Pigs were studied after 16 weeks of diet-induced MetS, MetS treated for the last 4 weeks with the mitochondria-targeted peptide elamipretide (ELAM, 0.1mg/kg SC q.d), and lean controls (n=6 each). Coronary artery and sinus blood samples were collected. EC mitochondrial density (electron microscopy), endothelial nitric oxide (eNOS) immunoreactivity (staining), myocardial microvascular density (3D micro-CT), and coronary endothelial function (organ bath) were assessed ex-vivo. The number and arteriovenous gradient of CD34+/KDR+ EPC was calculated by FACS (a negative gradient indicating EPC retention). Results: MetS and MetS+ELAM pigs developed similar MetS (obesity, hyperlipidemia, insulin resistance, and hypertension). EC mitochondrial density decreased in MetS compared to lean, but normalized in MetS+ELAM. ELAM also improved eNOS immunoreactivity, subendocardial microvascular density, and coronary endothelial function. ELAM-induced vasculoprotection was reflected in decreased coronary retention of EPCs. Conclusions: These observations underscore the role of mitochondria in regulating the cardiac circulation in experimental MetS, and the benefits of mitoprotection to preserve EC myocardial microvascular integrity.

Introduction: Transcatheter mitral valve replacement (TMVR) using aortic transcatheter heart valves (THV) is developing as an alternative to surgery for patients with severe mitral valve disease due to degenerated mitral bioprostheses or failed surgical rings who are poor surgical candidates. Outcomes of off-label procedures in the United States are being collected in the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy (STS/ACC TVT) Registry. A comprehensive analysis of mitral Valve-in-Valve (VIV) versus Valve-in-Ring (VIR) outcomes has not previously been performed. Objectives: To evaluate in-hospital and 30-day clinical outcomes of mitral VIV and VIR procedures in the United States. Methods: Retrospective analysis of data from the STS/ACC TVT Registry on patients who underwent mitral VIV or VIR procedures. Results: 587 patients underwent TMVR VIV (n=494) or VIR (n=93) procedures between January 2013 and December 2016 at 144 hospitals. Median age was 76 (VIV) and 73 (VIR) years, (p=0.024), 60.9% (VIV) and 44.1% (VIR) were female (p=0.003), median left ventricular ejection fraction was 55% in VIV and 50% in VIR (p <0.001), and median STS score was 10.5% (VIV) and 9.2% (VIR), p=0.131. Transseptal access was utilized in 35% VIV and 46.2% VIR procedures, p=0.081. Procedural success was achieved in 74.4% of VIV and 57.8%VIR (p=0.239). Left ventricular outflow tract (LVOT) obstruction was more common in VIR (5.4%) vs VIV (0.06%), p=0.003. Post-procedure median mean mitral valve gradient was 4mmHg in both groups. 95.7% of VIV and 86% of VIR patients had post-procedure mitral regurgitation ≤1(+), p<0.001. In-hospital mortality was 6.9% for VIV and 9.7% for VIR (p=0.343). 30-day mortality was 9% for VIV and 12% for VIR (p=0.387). At 30-day follow up, 85.6% of VIV and 77.7% of VIR patients were in New York Heart Association class I or II (p=0.398). Conclusions: TMVR VIV and VIR using aortic transcatheter heart valves in high surgical risk patients are associated with similar in-hospital and 30-day mortality and symptom benefit. LVOT obstruction post-TMVR and residual mitral regurgitation ≥2 (+) were more frequent in VIR procedures. The long-term effect of these procedures is not known and requires further evaluation.

Abstract: The liver is exposed to several harmful substances that bear the potential to cause excessive liver damage ranging from hepatitis and non-alcoholic fatty liver disease to extreme cases of liver cirrhosis and hepatocellular carcinoma. Liver ailments have been effectively treated from very old times with Chinese medicinal herbal formulations and later also applied by controlled trials in Japan. However, these traditional practices have been hardly well characterized in the past till in the last decades when more qualified studies have been carried out. Modern advances have given rise to specific molecular targets which are specifically good candidates for affecting the intricate mechanisms that play a role at the molecular level. These therapeutic regimens that mainly affect the progression of the disease by inhibiting the gene expression levels or by blocking essential molecular pathways or releasing cytokines may prove to play a vital role in minimizing the tissue damage. This review, therefore, tries to throw light upon the variation in the therapies for the treatment of benign and malignant liver disease from ancient times to the current date. Nonetheless, clinical research exploring the effectiveness of herbal medicines in the treatment of benign chronic liver diseases as well as prevention and treatment of HCC is still warranted.

Approximately one‐third of patients with metastatic castration‐resistant prostate cancer (CRPC) exhibited primary abiraterone resistance. To identify alternative treatment for abiraterone nonresponders, we performed drug discovery analyses using the L1000 database using differentially expressed genes identified in tumor biopsies and patient‐derived xenograft (PDX) tumors between abiraterone responders and nonresponders enrolled in PROMOTE trial. This approach identified 3 drugs, including topoisomerase II (TOP2) inhibitor mitoxantrone, CDK4/6 inhibitor palbociclib, and pan‐CDK inhibitor PHA‐793887. These drugs significantly suppressed the growth of abiraterone‐resistant cell lines and PDX models. Moreover, we identified 11 genes targeted by all 3 drugs that were associated with worse outcomes in both the PROMOTE and Stand Up To Cancer cohorts. This 11‐gene panel might also function as biomarkers to select the 3 alternative therapies for this subgroup of patients with CRPC, warranting further clinical investigation.

Abstract Background: The etiology of colorectal cancer is not fully understood. Methods: Using genetic variants and metabolomics data including 217 metabolites from the Framingham Heart Study (n = 1,357), we built genetic prediction models for circulating metabolites. Models with prediction R2 &gt; 0.01 (Nmetabolite = 58) were applied to predict levels of metabolites in two large consortia with a combined sample size of approximately 46,300 cases and 59,200 controls of European and approximately 21,700 cases and 47,400 controls of East Asian (EA) descent. Genetically predicted levels of metabolites were evaluated for their associations with colorectal cancer risk in logistic regressions within each racial group, after which the results were combined by meta-analysis. Results: Of the 58 metabolites tested, 24 metabolites were significantly associated with colorectal cancer risk [Benjamini–Hochberg FDR (BH-FDR) &lt; 0.05] in the European population (ORs ranged from 0.91 to 1.06; P values ranged from 0.02 to 6.4 × 10−8). Twenty one of the 24 associations were replicated in the EA population (ORs ranged from 0.26 to 1.69, BH-FDR &lt; 0.05). In addition, the genetically predicted levels of C16:0 cholesteryl ester was significantly associated with colorectal cancer risk in the EA population only (OREA: 1.94, 95% CI, 1.60−2.36, P = 2.6 × 10−11; OREUR: 1.01, 95% CI, 0.99−1.04, P = 0.3). Nineteen of the 25 metabolites were glycerophospholipids and triacylglycerols (TAG). Eighteen associations exhibited significant heterogeneity between the two racial groups (PEUR-EA-Het &lt; 0.005), which were more strongly associated in the EA population. This integrative study suggested a potential role of lipids, especially certain glycerophospholipids and TAGs, in the etiology of colorectal cancer. Conclusions: This study identified potential novel risk biomarkers for colorectal cancer by integrating genetics and circulating metabolomics data. Impact: The identified metabolites could be developed into new tools for risk assessment of colorectal cancer in both European and EA populations.

Introduction: Teleneonatology (TN) allows remote neonatologists to provide real-time audio-video telemedicine support to community hospitals when neonates require advanced resuscitation or critical care. Currently, there are no published economic evaluations of U.S. TN programs. Objective: To evaluate the cost of TN from the perspective of the health care system. Methods: We constructed a decision tree comparing TN to usual care for neonates born in hospitals without a neonatal intensive care unit (NICU) who require consultation. Our outcome of interest was total cost per patient, which included the incremental cost of a TN program, the cost of medical transport, and the cost of NICU or non-NICU hospitalization. We performed threshold sensitivity analyses where we varied each parameter to determine whether the base-case finding reverted. Results: For neonates requiring consultation after birth in a hospital without a NICU, TN was less costly ($16,878) than usual care ($28,047), representing a cost-savings of $11,168 per patient. Sensitivity analyses demonstrated that at least one of the following conditions would need to be met for TN to no longer be cost saving compared to usual care: transfer rate with usual care <12% (base-case = 82%), TN reducing the odds of transfer by <8% (base-case = 52%), or TN cost exceeding $12,989 per patient (base-case = $1,821 per patient). Conclusions: Economic modeling from the health system perspective demonstrated that TN was cost saving compared to usual care for neonates requiring consultation following delivery in a non-NICU hospital. Understanding the cost savings associated with TN may influence organizational decisions regarding implementation, diffusion, and retention of these programs.