Genome-Wide Association Study of Young-Onset Hypertension in the Han Chinese Population of Taiwan

Young-onset hypertension has a stronger genetic component than late-onset counterpart; thus, the identification of genes related to its susceptibility is a critical issue for the prevention and management of this disease. We carried out a two-stage association scan to map young-onset hypertension susceptibility genes. The first-stage analysis, a genome-wide association study, analyzed 175 matched case-control pairs; the second-stage analysis, a confirmatory association study, verified the results at the first stage based on a total of 1,008 patients and 1,008 controls. Single-locus association tests, multilocus association tests and pair-wise gene-gene interaction tests were performed to identify young-onset hypertension susceptibility genes. After considering stringent adjustments of multiple testing, gene annotation and single-nucleotide polymorphism (SNP) quality, four SNPs from two SNP triplets with strong association signals (−log10(p)>7) and 13 SNPs from 8 interactive SNP pairs with strong interactive signals (−log10(p)>8) were carefully re-examined. The confirmatory study verified the association for a SNP quartet 219 kb and 495 kb downstream of LOC344371 (a hypothetical gene) and RASGRP3 on chromosome 2p22.3, respectively. The latter has been implicated in the abnormal vascular responsiveness to endothelin-1 and angiotensin II in diabetic-hypertensive rats. Intrinsic synergy involving IMPG1 on chromosome 6q14.2-q15 was also verified. IMPG1 encodes interphotoreceptor matrix proteoglycan 1 which has cation binding capacity. The genes are novel hypertension targets identified in this first genome-wide hypertension association study of the Han Chinese population

Identification of IGF1, SLC4A4, WWOX, and SFMBT1 as Hypertension Susceptibility Genes in Han Chinese with a Genome-Wide Gene-Based Association Study

Hypertension is a complex disorder with high prevalence rates all over the world. We conducted the first genome-wide gene-based association scan for hypertension in a Han Chinese population. By analyzing genome-wide single-nucleotide-polymorphism data of 400 matched pairs of young-onset hypertensive patients and normotensive controls genotyped with the Illumina HumanHap550-Duo BeadChip, 100 susceptibility genes for hypertension were identified and also validated with permutation tests. Seventeen of the 100 genes exhibited differential allelic and expression distributions between patient and control groups. These genes provided a good molecular signature for classifying hypertensive patients and normotensive controls. Among the 17 genes, IGF1, SLC4A4, WWOX, and SFMBT1 were not only identified by our gene-based association scan and gene expression analysis but were also replicated by a gene-based association analysis of the Hong Kong Hypertension Study. Moreover, cis-acting expression quantitative trait loci associated with the differentially expressed genes were found and linked to hypertension. IGF1, which encodes insulin-like growth factor 1, is associated with cardiovascular disorders, metabolic syndrome, decreased body weight/size, and changes of insulin levels in mice. SLC4A4, which encodes the electrogenic sodium bicarbonate cotransporter 1, is associated with decreased body weight/size and abnormal ion homeostasis in mice. WWOX, which encodes the WW domain-containing protein, is related to hypoglycemia and hyperphosphatemia. SFMBT1, which encodes the scm-like with four MBT domains protein 1, is a novel hypertension gene. GRB14, TMEM56 and KIAA1797 exhibited highly significant differential allelic and expressed distributions between hypertensive patients and normotensive controls. GRB14 was also found relevant to blood pressure in a previous genetic association study in East Asian populations. TMEM56 and KIAA1797 may be specific to Taiwanese populations, because they were not validated by the two replication studies. Identification of these genes enriches the collection of hypertension susceptibility genes, thereby shedding light on the etiology of hypertension in Han Chinese populations

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Reduction of circulating endothelial progenitor cell level is associated with contrast-induced nephropathy in patients undergoing percutaneous coronary and peripheral interventions.

OBJECTIVES: Reduced number and impaired function of circulating endothelial progenitor cells (EPCs) in patients with chronic kidney disease have been reported. However, there is little data about the association between circulating EPC levels and risk of contrast-induced nephropathy (CIN). The aim of this study was to investigate the relationship between circulating EPCs and CIN in patients after angiography. METHODS AND RESULTS: A total of 77 consecutive patients undergoing elective percutaneous coronary intervention (PCI) and percutaneous transluminal angioplasty (PTA) were enrolled. Flow cytometry with quantification of EPC markers (defined as CD34+, CD34+KDR+, and CD34+KDR+CD133+) in peripheral blood samples was used to assess EPC number before the procedure. CIN was defined as an absolute increase ≧0.5 mg/dl or a relative increase ≧25% in the serum creatinine level at 48 hours after the procedure. Eighteen (24%) of the study subjects developed CIN. Circulating EPC levels were significantly lower in patients who developed CIN than in those without CIN (CD34+KDR+, 4.11±2.59 vs. 9.25±6.30 cells/105 events, P<0.001). The incidence of CIN was significantly greater in patients in the lowest EPC tertile (CD34+KDR+; from lowest to highest, 52%, 15%, and 4%, P<0.001). Using univariate logistic regression, circulating EPC number (CD34+KDR+) was a significant negative predictor for development of CIN (odds ratio 0.69, 95% CI 0.54-0.87, P = 0.002). Over a two-year follow-up, patients with CIN had a higher incidence of major adverse cardiovascular events including myocardial infarction, stroke, revascularization of treated vessels, and death (66.7% vs. 25.4%, P = 0.004) than did patients without CIN. CONCLUSIONS: Decreased EPC level is associated with a greater risk of CIN, which may explain part of the pathophysiology of CIN and the poor prognosis in CIN patients

The Phenoxyphenol Compound 4-HPPP Selectively Induces Antiproliferation Effects and Apoptosis in Human Lung Cancer Cells through Aneupolyploidization and ATR DNA Repair Signaling

Lung cancer is a leading cause of cancer death worldwide, and non-small-cell lung cancer (NSCLC) accounts for 85% of lung cancer, which is highly metastatic, leading to the poor survival rate of patients. We recently reported that 4-[4-(4-hydroxyphenoxy)phenoxy]phenol (4-HPPP), a phenoxyphenol, exerts antihepatoma effects by inducing apoptosis and autophagy. In this study, we further examined the effect of 4-HPPP and its analogs on NSCLC cells. Colony formation assays showed that 4-HPPP exerts selective cytotoxicity against NSCLC H1299 cells; furthermore, the inhibitory effect of 4-HPPP on the proliferation and migration of NSCLC cells was validated using an in vivo zebrafish-based tumor xenograft assay. The flow cytometry-based dichlorofluorescein diacetate (DCF-DA) assays indicated that 4-HPPP caused an increase in reactive oxygen species (ROS) in NSCLC cells, and Western blot assays showed that the major ROS scavenging enzymes superoxide dismutases- (SODs-) 1/2 were upregulated, whereas peroxidase (PRX) was downregulated. Furthermore, 4-HPPP caused both aneuploidization and the accumulation of γH2AX, a sensor of DNA damage, as well as the activation of double-strand break (DSB) markers, especially Ataxia-telangiectasia-mutated and Rad3-related (ATR) in NSCLC cells. Our present work suggests that the antiproliferative effects of 4-HPPP on lung cancer cells could be due to its phenoxyphenol structure, and 4-HPPP could be a candidate molecule for treating NSCLC by modulating ROS levels and lowering the threshold of polyploidy-specific cell death in the future

Sleep apnea and risk of aortic dissection: A nonrandomized, pair-matched cohort study

Background: Sleep apnea (SA) was associated with increased prevalence of aortic dissection (AD) in studies that were criticized for either their small sample size or lack of prospective observation. Using a considerably larger nationwide, population-based database and a long-term prospective cohort design, our study strived to explore the relationship between SA and the subsequent development of AD. Methods: From 2000 to 2007, we gathered a study cohort consisting of 15,848 newly diagnosed cases of SA from Taiwan’s National Health Insurance Research Database. For the control group, another 39,826 individuals without SA were matched for age, sex, and comorbidity. The two cohorts were followed-up to observe the occurrence of AD. Results: During an average 3.59 ± 2.41 years of follow-up, we observed 33 cases of new AD occurrence [non-SA (22, 0.1%) vs. SA (11, 0.1%), p=0.669], and the incidence of AD was similar for both groups. After adjusting for age, sex, and comorbidity, only age [hazard ratio (HR) 1.03; 95% confidence interval (CI), 1.01–1.06; p=0.006], male gender (HR 2.49; 95% CI, 1.07–5.79; p=0.034), and hypertension (HR 6.28; 95% CI, 2.36–16.67; p<0.001) were independently associated with AD diagnosis. Conclusion: SA was not associated with an increased risk of AD using a large nationwide cohort database. Nonetheless, larger prospective studies or meta-analyses are recommended to confirm our findings

Evaluating the Accuracy of Morphological Identification of Larval Fishes by Applying DNA Barcoding

<div><p>Due to insufficient morphological diagnostic characters in larval fishes, it is easy to misidentify them and difficult to key to the genus or species level. The identification results from different laboratories are often inconsistent. This experiment aims to find out, by applying DNA barcoding, how inconsistent the identifications can be among larval fish taxonomists. One hundred morphotypes of larval fishes were chosen as test specimens. The fishes were collected with either larval fish nets or light traps in the northern, southern and northwestern waters of Taiwan. After their body lengths (SL) were measured and specimen photos were taken, all specimens were delivered, in turn, to five laboratories (A–E) in Taiwan to be identified independently. When all the results were collected, these specimens were then identified using COI barcoding. Out of a total of 100 specimens, 87 were identified to the family level, 79 to the genus level and 69 to the species level, based on the COI database currently available. The average accuracy rates of the five laboratories were quite low: 80.1% for the family level, 41.1% for the genus level, and 13.5% for the species level. If the results marked as “unidentified” were excluded from calculations, the rates went up to 75.4% and 43.7% for the genus and species levels, respectively. Thus, we suggest that larval fish identification should be more conservative; i.e., when in doubt, it is better to key only to the family and not to the genus or species level. As to the most misidentified families in our experiment, they were Sparidae, Scorpaenidae, Scombridae, Serranidae and Malacanthidae. On the other hand, <em>Mene maculata</em> and <em>Microcanthus strigatus</em> were all correctly identified to the species level because their larvae have distinct morphology. Nevertheless, barcoding remains one of the best methods to confirm species identification.</p> </div

Association between previous history of gout attack and risk of deep vein thrombosis - a nationwide population-based cohort study

[[abstract]]Although the association of hyperuricemia and cardiovascular diseases is well established by previous research studies, the relationship between gout and deep vein thrombosis (DVT) remains unclear. We conducted a nationwide longitudinal cohort study to investigate the relationship between gout and DVT. We used the Taiwan National Health Insurance Research Database to identify patients with gout diagnosed in Taiwan during 2000-2011, and we followed up these patients to determine the incidence of DVT among them. The association between gout and DVT was analyzed by cox proportional hazard model. The study cohort included 35,959 patients with history of gout attack and 35,959 matched controls without gout attack. During the median follow-up of 7.5 +/- 3.6 years, the incidence rate of DVT was significantly higher in patients with gout than that in control group (13.48 versus 9.77 per 10(4) person-years, p < 0.001). Kaplan-Meier analysis revealed a tendency toward DVT development in gout patients (log rank test, p < 0.001). In a Cox model, patients with gout were found to have a 1.38-fold (95% confidence interval [CI], 1.18 to 1.62, p < 0.001) higher risk of developing DVT. Hyperuricemia with gout attack could be a possible risk predictor for DVT, but these findings need to be confirmed in future clinical and experimental studies

Prediction of vascular dementia and Alzheimer's disease in patients with atrial fibrillation or atrial flutter using CHADS2 score

Background: Atrial fibrillation (AF) is associated with an increased risk of dementia. However, limited data are available on the predictors of dementia in patients with AF. This study aimed to evaluate whether the CHADS2 score could be a useful tool for risk stratification with regard to dementia occurrence among patients with AF. Methods: AF patients were identified from the National Health Insurance sampling database, which has accumulated a total of 1,000,000 participants since 2000. After excluding patients diagnosed with dementia prior to the index day of enrollment, CHADS2 score was measured to investigate its association with the occurrence of dementia, including vascular dementia and Alzheimer's disease. Results: During the mean follow-up period of 3.71 ± 2.78 years, 1135 dementia cases (7.36%) were identified, including 241 cases of vascular dementia and 894 cases of Alzheimer's disease. In multivariate analysis, an increase of 1 point in the CHADS2 score was independently associated with a 54% increase in the risk of vascular dementia (hazard ratio = 1.54; 95% confidence interval, 1.41–1.69; p < 0.001) and a 40% increase in Alzheimer's disease (hazard ratio = 1.40; 95% confidence interval, 1.34–1.46; p < 0.001). Conclusion: CHADS2 score is a useful predictor for the development of vascular dementia as well as Alzheimer's disease in patients with AF

The two specimens of three morphotypes (No. 12, 83, and 90) were identified as different species or families, but were proven to be identical species through barcoding.

<p>Shown here: <i>Katsuwonus pelamis</i> 4.8 and 4.2 mm SL (12a and 12b); Tripterygiidae 9.5 and 9.3 mm (83a and 83b); and <i>Abudefduf vaigiensis</i> 2.8 and 3.0 mm (90a and 90b).</p