Association of elevated inflammatory and endothelial biomarkers with prehypertension among Mongolians in China

Chronic inflammation and endothelial dysfunction may be associated with hypertension and cardiovascular disease. We examined associations between inflammatory and endothelial dysfunction biomarkers and the risk of prehypertension among Mongolians. A cross-sectional study was conducted among 2589 Mongolians aged 20 years and older in Inner Mongolia, China. Three blood pressure measurements, body weight, height and lifestyle factors were obtained for all participants. Overnight fasting blood samples were obtained to measure the biomarkers, including C-reactive protein (CRP), soluble intercellular adhesion molecule-1 (sICAM-1), soluble E-selectin (sE-selectin) and angiotensin II. The average levels of CRP (7.43 vs. 5.86), sICAM-1 (339.38 vs. 328.05), sE-selectin (19.11 vs. 18.32) and angiotensin II (52.00 vs. 47.00) were all significantly higher in hypertensives than that in prehypertensives (all P<0.05); prehypertensives had higher levels of CRP (5.86 vs. 4.85) and sICAM-1 (328.05 vs. 314.14) compared with normotensives (both P<0.05). Hypertension (odds ratio (OR): 1.50, 95% confidence interval (CI): 1.07, 2.11) and prehypertension (OR: 1.38, 95% CI: 1.02, 1.85) were positively and significantly associated with elevated CRP adjusted for multivariable. Hypertension (OR: 1.56, 95% CI: 1.18, 2.06) and prehypertension (OR: 1.32, 95% CI: 1.02, 1.71) were also positively and significantly associated with higher sICAM-1 adjusted for age and gender. Elevated CRP and sICAM-1 were associated with prehypertension among Mongolian population. This study suggests that inflammation and endothelial dysfunction may have a role in the development of hypertension.

Prehypertension and insulin resistance among Mongolian people, Inner Mongolia, China

BACKGROUND

There is little knowledge on association of prehypertension with insulin resistance among Mongolian people. The purpose of the present study is to explore whether there are phenomena of insulin resistance in the phase of prehypertension in the Mongolian population.

METHODS

2553 Mongolian people were included in the present analysis. Data on demographic characteristics, lifestyle risk factors, family history of hypertension and medical history were obtained, blood pressure, body weight, height and waist circumference measured, fasting blood samples collected and blood lipids, fast plasma glucose and insulin determined for all individuals.

RESULTS

Among participants who are overweight, the means of the homeostatic model assessment of insulin resistance (HOMA-IR) were significantly higher in prehypertensives than those in normotensives. Prehypertension was significantly associated with the higher levels of HOMA-IR after multivariate adjustment. Compared with HOMA-IRs < 1.64, multivariate-adjusted ORs (95% CI) for HOMA-IRs of 1.64-2.32, 2.33-2.84, 2.85-3.76 and ≥3.76 were 1.056 (0.786-1.418), 1.565 (1.158-2.116), 1.381 (1.020-1.870) and 1.435 (1.046-1.970), respectively.

CONCLUSIONS

Prehypertension was significantly associated with insulin resistance in the Mongolian population, and this study suggest that insulin resistance may play an important role in development of hypertension.

Functional analysis of multiple genomic signatures demonstrates that classification algorithms choose phenotype-related genes

Gene expression signatures of toxicity and clinical response benefit both safety assessment and clinical practice; however, difficulties in connecting signature genes with the predicted end points have limited their application. The Microarray Quality Control Consortium II (MAQCII) project generated 262 signatures for ten clinical and three toxicological end points from six gene expression data sets, an unprecedented collection of diverse signatures that has permitted a wide-ranging analysis on the nature of such predictive models. A comprehensive analysis of the genes of these signatures and their nonredundant unions using ontology enrichment, biological network building and interactome connectivity analyses demonstrated the link between gene signatures and the biological basis of their predictive power. Different signatures for a given end point were more similar at the level of biological properties and transcriptional control than at the gene level. Signatures tended to be enriched in function and pathway in an end point and model-specific manner, and showed a topological bias for incoming interactions. Importantly, the level of biological similarity between different signatures for a given end point correlated positively with the accuracy of the signature predictions. These findings will aid the understanding, and application of predictive genomic signatures, and support their broader application in predictive medicine.

Genomic indicators in the blood predict drug-induced liver injury

Genomic biomarkers for the detection of drug-induced liver injury (DILI) from blood are urgently needed for monitoring drug safety. We used a unique data set as part of the Food and Drug Administration led MicroArray Quality Control Phase-II (MAQC-II) project consisting of gene expression data from the two tissues (blood and liver) to test cross-tissue predictability of genomic indicators to a form of chemically induced liver injury. We then use the genomic indicators from the blood as biomarkers for prediction of acetaminophen-induced liver injury and show that the cross-tissue predictability of a response to the pharmaceutical agent (accuracy as high as 92.1%) is better than, or at least comparable to, that of non-therapeutic compounds. We provide a database of gene expression for the highly informative predictors, which brings biological context to the possible mechanisms involved in DILI. Pathway-based predictors were associated with inflammation, angiogenesis, Toll-like receptor signaling, apoptosis, and mitochondrial damage. The results show for the first time and support the hypothesis that genomic indicators in the blood can serve as potential diagnostic biomarkers predictive of DILI.

A comparison of batch effect removal methods for enhancement of prediction performance using MAQC-II microarray gene expression data

Batch effects are the systematic non-biological differences between batches (groups) of samples in microarray experiments due to various causes such as differences in sample preparation and hybridization protocols. Previous work focused mainly on the development of methods for effective batch effects removal. However, their impact on cross-batch prediction performance, which is one of the most important goals in microarray-based applications, has not been addressed. This paper uses a broad selection of data sets from the Microarray Quality Control Phase II (MAQC-II) effort, generated on three microarray platforms with different causes of batch effects to assess the efficacy of their removal. Two data sets from cross-tissue and cross-platform experiments are also included. Of the 120 cases studied using Support vector machines (SVM) and K nearest neighbors (KNN) as classifiers and Matthews correlation coefficient (MCC) as performance metric, we find that Ratio-G, Ratio-A, EJLR, mean-centering and standardization methods perform better or equivalent to no batch effect removal in 89, 85, 83, 79 and 75% of the cases, respectively, suggesting that the application of these methods is generally advisable and ratio-based methods are preferred.

Fiber optical parametric oscillator for sub-50 fs pulse generation: optimization of fiber length

We demonstrate generation of 48fs pulses with linear chirp using a short (27mm) fiber optical parametric oscillator (FOPO), which is synchronously pumped by a mode-locked ytterbium-doped fiber laser. We also study the pulse quality for both the short- and long-wavelength operation where the fiber length inside of the oscillator varies from 17 to 61mm. The optimal pulse duration is observed only in the short-wavelength operation. Furthermore, we model the FOPO system as a single-pass parametric amplifier including dispersive pulse broadening and walk-off between the pump and output. The optimal condition arises from the minimization of the walk-off and dispersion. When walk-off is large, the parametric amplification process is most efficient over some reduced effective fiber length, leading to an upper limit in the amount of the observed pulse broadening.

Effects of cigarette smoking on blood pressure stratified by BMI in Mongolian population, China

BACKGROUND

The relationship between smoking and hypertension is still unclear and controversial; we examine effects of smoking on blood pressure stratified by body mass index (BMI) in the Mongolian population.

METHODS

A total of 2589 Mongolians aged 20 years or more were recruited as study subjects. Demographic data, lifestyle factors, family history of hypertension, blood pressure measurements, physical examination and blood sample were obtained and analyzed for all subjects.

RESULTS

Among subjects with BMI<25 kg/m(2), adjusted mean diastolic blood pressure in all smokers (82, 83 and 82 mmHg for subjects who smoke 1-9, 10-19 and >20 cigarettes/day, respectively) were lower than that in non-smokers (84 mmHg), all p-values <0.05; among subjects with BMI>25 kg/m(2), mean systolic blood pressure (137 mmHg for non-smokers, 141, 135 and 132 mmHg for subjects who smoke 1-9, 10-19 and >20 cigarettes/day, respectively) decreased with amount of smoking and linear trend was statistically significant, p<0.05. Multivariate adjusted odds ratios of hypertension for three smoking groups were all not statistically significant.

CONCLUSIONS

This study did not provide support that smoking was a risk factor of hypertension and elevated blood pressure.

Biomarkers of inflammation, endothelial dysfunction and insulin resistance in adults of Inner Mongolia, China

BACKGROUND

Low-grade chronic inflammation and endothelial dysfunction have been hypothesized to underlie the constellation of cardiometabolic risk factors, possibly by inducing insulin resistance. In the present study, we investigated associations between inflammation, endothelial dysfunction biomarkers and insulin resistance [measured by homeostasis model assessment of insulin resistance (HOMA-IR)] in a large community population.

METHODS

We conducted a cross-sectional study among 2589 participants aged 20 years and older in Inner Mongolia, China. Overnight fasting blood samples were obtained to measure the plasma glucose, serum insulin and biomarkers including C-reactive protein (CRP), soluble inter-cellular adhesion molecule-1 (sICAM-1), soluble E-selectin (sE-selectin) and angiotensin II.

RESULTS

Among the residents of Inner Mongolia, levels of C-reactive protein (7.58 versus 5.63), soluble E-selectin (20.69 versus 17.93) and angiotensin II (51.80 versus 48.00) were all significantly higher in individuals with a higher HOMA-IR than in those with lower HOMA-IR. Higher HOMA-IR was also positively and significantly (p < 0.05) associated with higher C-reactive protein (odds ratio 1.47, 95% confidence interval 1.19, 1.82), and higher soluble E-selectin (odds ratio 1.53, 95% confidence interval 1.24, 1.88), adjusted for multivariables.

CONCLUSIONS

Elevated C-reactive protein and soluble E-selectin were associated with higher HOMA-IR among residents of Inner Mongolia. This study suggests that inflammation and endothelial dysfunction may relate to insulin resistance.

Impaired fasting glucose and cardiovascular risk factor clustering among Mongolian population in rural and animal husbandry area, Inner Mongolia, China

AIMS

The aims of this study is to assess whether and to what extent there is clustering of cardiovascular risk factors in the IFG phase in the Mongolian population, China.

METHODS

Total 2589 Mongolians aged 20 years or more were recruited as study subjects. Data on demographic characteristics, lifestyle risk factors, family history of hypertension, medical history and fasting plasma glucose were obtained, and relationship between clustering of cardiovascular risk factors and risk of IFG and diabetes analyzed for all individuals.

RESULTS

The proportions of 3 risk factors clustering were higher in diabetes than in IFG, and higher in IFG than in normal FPG (both P<0.01). After adjustment for age and sex, both IFG and diabetes were associated with mutually clustering of 6 risk factors; odds ratio (OR) of IFG associated with 1, 2 and >or=3 factors was 1.43 (1.02, 1.99), 2.22 (1.58, 3.12) and 4.49 (3.24, 6.22), respectively, and OR of diabetes associated with 1, 2 and >or=3 factors was 2.01 (0.70, 5.76), 5.47 (2.03, 14.71) and 14.30 (5.55, 36.83), respectively.

CONCLUSIONS

There was clustering of risk factors in the phase of IFG among Mongolian people, so intervention measures should be taken to prevent diabetes and other cardiovascular diseases among the individuals with IFG.

Assessing sources of inconsistencies in genotypes and their effects on genome-wide association studies with HapMap samples

The discordance in results of independent genome-wide association studies (GWAS) indicates the potential for Type I and Type II errors. We assessed the repeatibility of current Affymetrix technologies that support GWAS. Reasonable reproducibility was observed for both raw intensity and the genotypes/copy number variants. We also assessed consistencies between different SNP arrays and between genotype calling algorithms. We observed that the inconsistency in genotypes was generally small at the specimen level. To further examine whether the differences from genotyping and genotype calling are possible sources of variation in GWAS results, an association analysis was applied to compare the associated SNPs. We observed that the inconsistency in genotypes not only propagated to the association analysis, but was amplified in the associated SNPs. Our studies show that inconsistencies between SNP arrays and between genotype calling algorithms are potential sources for the lack of reproducibility in GWAS results.

Some features of the photonic crystal fiber temperature sensor with liquid ethanol filling

We introduce a novel photonic crystal fiber (PCF) temperature sensor that is based on intensity modulation and liquid ethanol filling of air holes with index-guiding PCF. The mode field, the effective refractive index and the confinement loss of PCF were all found to become highly temperature-dependent when the thermo-optic coefficient of the liquid ethanol used is higher than that of silicon dioxide and this temperature dependence is an increasing function of the d/Lambda ratio and the input wavelength. All the experiments and simulations are discussed in this paper and the temperature sensitivity of transmission power was experimentally determined to be 0.315 dB/ degrees C for a 10-cm long PCF.

High order resonances between core mode and cladding supermodes in long period fiber gratings inscribed in photonic bandgap fibers

High order resonances between fundamental core mode and cladding LP(01) supermodes are demonstrated in long period fiber gratings (LPFGs) inscribed in all-solid photonic bandgap fibers for the first time to our knowledge. The resonance wavelengths of the LPFGs calculated by way of photonic bandgap theory agree with the experimental results. The temperature responses of these resonance peaks have been theoretically and experimentally investigated. In addition, the mechanism of LPFG formation has been researched deeply through coupled-mode theory (CMT) and the cutback experiments.

Photonic crystal fiber based Mach-Zehnder interferometer for DPSK signal demodulation

We demonstrate a novel fiber-based in-line DPSK demodulator using an in-fiber Mach-Zehnder interferometer (MZI). The device is fabricated by mismatch splicing of a photonic crystal fiber (PCF) with standard single mode fibers. The spectral characteristics at different PCF lengths are analyzed. The envelope of the interference fringes show a period that is inversely proportional to the PCF length, and is attributed to the periodic coupling between the core mode and the cladding mode. Error free demodulations of 10-Gb/s RZ- and NRZ-DPSK signals have been demonstrated using the in-fiber PCF-MZI demodulator with only 3-m PCF to introduce 91-ps delay. Wideband DPSK demodulation has also been achieved.

Effects of bone morphogenetic protein-2 on proliferation and angiogenesis in oral squamous cell carcinoma

Experimental data and limited patient experience suggest that rhBMP-2 can be used to regenerate bone in acquired segmental defects of the mandible. Most of these defects are caused by resection of oral squamous cell carcinoma (OSCC) and the biologic effects of rhBMP-2 on these carcinoma cells are unknown. The objective of this study was to determine whether rhBMP-2 produces adverse effects on proliferation and angiogenesis in OSCC, two biologic processes critical to tumor formation. In vitro studies included treating OSCC cells with rhBMP-2 or an adenoviral vector containing the cDNA for BMP-2. In vivo studies involved co-transplantation of OSCC cells with bone marrow stromal cells genetically modified to over express BMP-2, to mimic a clinically relevant scenario for regenerating bone using cell-based therapy in a wound containing microscopic residual disease. Proliferation, as measured by a MTT assay in vitro and tumor growth in vivo was not affected by treatment with BMP-2. Angiogenesis, measured by secretion of the proangiogenic molecules VEGF and IL-8 in vitro and microvessel density in vivo, was not affected. Exposure of OSCC cells to BMP-2 does not stimulate proliferation or angiogenesis. Further studies are needed before using rhBMP-2 for bone tissue engineering in oral cancer-related defects.

Diabetes and impaired fasting glucose in Mongolian population, Inner Mongolia, China

AIMS

The aims of this study is to assess the prevalence of diabetes and IFG and compare the risk factors between diabetes and IFG in the Mongolian population, China.

METHODS

Data on demographic characteristics, lifestyle risk factors, family history of hypertension, medical history and fasting plasma glucose were obtained and analyzed for all individuals.

RESULTS

Total 2589 Mongolians aged 20 years or more were recruited as study subjects. The overall prevalence of diabetes and IFG was 3.7% (males 3.9%; females 3.5%) and 18.5% (males 17.7%; females 19.0%), respectively. Multivariate logistic analysis showed that diabetes was significantly associated with age (odds ratio: 1.26), overweight (1.86), high triglycerides (1.96), family history of hypertension (1.86), heart rate (1.05) and high C-reactive protein (3.59), and IFG significantly associated with age (odds ratio: 1.11), low high-density lipoprotein-cholesterol (1.80), family history of hypertension (1.60), heart rate (1.03) and high C-reactive protein (2.73).

CONCLUSIONS

IFG were common among Mongolian people living in the northeast of China. IFG has partly same risk factors as diabetes, and prevalence of some cardiovascular risk factors and number of risk factor in diabetes were higher than that in IFG.

Admission blood pressure indexes and risk of in-hospital death and dependency among acute hemorrhagic stroke patients, Inner Mongolia, China

PURPOSE

To study the association between blood pressure (BP) SBP, DBP, mean arterial pressure (MAP) and pulse pressure (PP) and clinical outcome in acute hemorrhagic stroke patients in the Chinese population.

METHODS

1,760 hemorrhagic stroke patients admitted to six hospitals from January 1, 2003 to December 31, 2005 were included in the study. BP and other variables were collected within the first 24-hr of admission. Clinical outcomes at discharge were evaluated by neurologists. Multivariate-adjusted odds ratios associated with increment of 1 standard deviation (SD) mmHg in four BP were determined by multiple logistic regression analysis.

RESULTS

The four BP indexes at admission were positively associated with death and SBP, DBP, MAP were associated with dependency. Adjusted odds ratios (95% confident interval) of death associated with increment of 1 SD mmHg were 1.74 (1.44,2.12), 1.39 (1.15,1.69),1.61 (1.32,1.96) and 1.66 (1.39,1.99) for SBP, DBP, MAP and PP, respectively (all P < 0.01), and adjusted odds ratio of dependency associated with increment of 1 SD mmHg was 1.15 (1.03,1.27), 1.21 (1.09,1.34) and 1.19 (1.07,1.32) for SBP, DBP and MAP, respectively (all P < 0.05).

CONCLUSION

Increased SBP, DBP, MAP and PP at admission were all associated with in-hospital mortality, and increased SBP, DBP and MAP were associated with dependency at discharge among hemorrhagic stroke patients.

Toluene diisocyanate enhances human bronchial epithelial cells' permeability partly through the vascular endothelial growth factor pathway

BACKGROUND

Toluene diisocyanate (TDI) is a recognized chemical asthmogen; yet, the mechanisms of its toxicity have not been elucidated.

OBJECTIVE

To investigate the influence of TDI on the permeability of human bronchial epithelial cell (HBE; HBE135-E6E7) monolayers in vitro, and the expression of vascular endothelial growth factor (VEGF) in these cells.

METHODS

TDI-human serum albumin (HSA) conjugates were prepared by a modification of Son's method. Fluorescein isothiocyanate-labelled dextran and transmission electron microscopy were used to evaluate the effects of TDI-HSA on HBE135-E6E7 permeability. RT-PCR and ELISA were used to evaluate VEGF gene expression and protein release from HBE135-E6E7 cells stimulated by TDI-HSA. A VEGF-neutralizing antibody was used in monolayer permeability experiments to determine the role of the VEGF pathway in this process.

RESULTS

TDI-HSA significantly increased the permeability coefficients of HBE135-E6E7 monolayers (P<0.01). TDI-HSA treatment significantly increased the expression of VEGF165 and VEGF189 genes (P<0.01). ELISA showed that TDI significantly induces VEGF release from HBE135-E6E7 cells. Cells treated with TDI-HSA and VEGF-neutralizing antibody had significantly lower permeability coefficients than cells treated with TDI-HSA only (P<0.01), but still significantly higher than control cells (P<0.01). Cells treated with TDI-HSA had fewer tight junctions (TJs) than control and HSA-treated cells, and addition of the anti-VEGF antibody did not restore the original number of TJs.

CONCLUSION

TDI increases the permeability of HBE cell monolayers, partly through a VEGF-mediated pathway. This suggests the importance of VEGF in TDI-induced pulmonary diseases, but shows that other pathways may be involved in the pathogenic process.

Prehypertension and cardiovascular risk factor clustering among Mongolian population in rural and animal husbandry area, Inner Mongolia, China

BACKGROUND

It is unclear whether and to what extent there is clustering of cardiovascular risk factors in the prehypertension phase among Mongolians in the rural and animal husbandry area of Inner Mongolia, China.

METHODS AND RESULTS

The 2,589 Mongolian people aged > or=20 years served as subjects. Demographic data, lifestyle factors and family history of hypertension, blood pressure measurements, physical examination and blood samples were obtained and analyzed for all individuals. The proportions of 2 and > or =3 risk factors clustering were higher in hypertensives than in prehypertensives, and higher in prehypertensives than in normotensives (both P<0.01). After adjustment for age, sex and family history of hypertension, both prehypertension and hypertension were associated with mutually clustering of 5 risk factors; odds ratio (OR) of prehypertension with 1, 2 and > or =3 factors was 1.30 (1.02, 1.65), 1.93 (1.40, 2.67) and 2.44 (1.62, 3.68), respectively, and for hypertension the OR were 1.75 (1.31, 2.35), 3.84 (2.68, 5.48) and 6.95 (5.04, 10.63), respectively.

CONCLUSIONS

There is clustering of risk factors in the phase of prehypertension among Mongolian people, so intervention measures should be taken to prevent progression to hypertension and other cardiovascular diseases.