Tumor characterization with dynamic contrast-enhanced MRI using MR contrast agents of various molecular weights

Dynamic contrast-enhanced MR imaging was used to measure the kinetics of enhancement in three different animal tumor models (Walker 256, R3230 AC, MCF7) using three different Gd complexes (Gd-DTPA, Gd-DTPA-24-cascade-polymer 30 kD, and polylysine-Gd-DTPA 50 kD). The three tumor models varied in growth rate, with the most rapid growth demonstrated by Walker 256 cells and the slowest growth occurring in the MCF7 cells. For each tumor, the kinetics of enhancement using polylysine-Gd-DTPA was analyzed using a pharmacokinetic model to estimate the vascular volume of the tumor. The rate of entry of the contrast agent into the interstitial space served as the measure of vascular permeability. The smallest molecular-weight agent, Gd-DTPA, could not provide information about vascular permeability. The intermediate and the largest agents both demonstrated that the faster-growing Walker 256 tumor had greater vascular permeability than did the slower-growing R3230 AC tumor. The degree of vascular permeability in the MCF7 tumor could not be assessed fairly due to insufficient statistics. The current study provides evidence supporting the hypothesis that more rapidly growing tumors have higher vascular permeability than do tumors that grow more slowly.

Prevalence and Influencing Factors of Metabolic Syndrome among Adults in China from 2015 to 2017

The prevalence and influencing factors of metabolic syndrome (MetS) in Chinese residents aged 20 or older were investigated. The data were collected from China Nutrition and Health Surveillance (2015–2017), which used a stratified, multistage, random sampling method. A total of 130,018 residents aged 20 years or older from 31 provinces were included in this study. The National Cholesterol Education Programme Adult Treatment Panel III (NCEP ATP III) criteria were used to define MetS. The standardised prevalence of high waist circumference, high blood pressure and low high-density lipoprotein cholesterol were 40.8%, 49.4% and 41.1%, respectively. The following factors were associated with a higher prevalence of MetS: female [odds ratio (OR) = 1.773, 95% CI = 1.709–1.840]; older age (OR = 1.037, 95% CI = 1.036–1.039); living in north China (OR = 1.087, 95% CI = 1.058–1.117); high body mass index (OR = 1.402, 95% CI = 1.395–1.408); higher income [OR (95% CI): 1.044 (1.007–1.083), 1.083 (1.044–1.124) and 1.123 (1.078–1.170) for moderate, high, and very high income, respectively]; family history of hypertension (OR = 1.237, 95% CI = 1.203–1.273); family history of diabetes (OR = 1.491, 95% CI = 1.426–1.558) and current smoking status (OR = 1.143, 95% CI = 1.098–1.191). Living in the countryside (OR = 0.960, 95% CI = 0.932–0.988), moderate alcohol consumption (OR = 0.917, 95% CI = 0.889–0.946) and being physically active (OR = 0.887, 95% CI = 0.862–0.913) were associated with a lower prevalence of MetS. The prevalence of MetS among residents aged 20 years or older in China is increasing, especially among women, people aged 45 years or older and urban residents. Preventive efforts, such as quitting smoking and engaging in physical activity, are recommended to reduce the risk of MetS.

Short-term effects of the 2008 cold spell on mortality in three subtropical cities in Guangdong Province, China

BACKGROUND

Few studies have been conducted to investigate the impact of extreme cold events on mortality in subtropical regions.

OBJECTIVE

In the present study we aimed to investigate the effects of the 2008 cold spell on mortality and the possibility of mortality displacement in three subtropical cities in China.

METHODS

Daily mortality, air pollution, and weather data were collected from 2006 to 2009 in Guangzhou, Nanxiong (no air pollutants), and Taishan. We used a polynomial distributed lag model (DLM) to analyze the relationship between the 2008 cold spell and mortality. To observe the mortality displacement of the cold spell, we estimated the cumulative effects at lag0, lag0-6, lag0-13, lag0-20, and lag0-27 separately.

RESULTS

During the 2008 cold spell, the cumulative risk of nonaccidental mortality increased significantly in Guangzhou [relative risk (RR) = 1.60; 95% CI: 1.19, 2.14] and Taishan (RR = 1.60; 95% CI: 1.06, 2.40) when lagged up to 4 weeks after the cold spell ended. Estimated effects at lag0-27 were more pronounced for males than for females, for respiratory mortality than for cardiovascular mortality, and for the elderly (≥ 75 years of age) than for those 0-64 years of age. Most of the cumulative RRs increased with longer lag times in Guangzhou and Taishan. However, in Nanxiong, the trend with cumulative RRs was less consistent, and we observed no statistically significant associations at lag0-27.

CONCLUSION

We found associations between the 2008 cold spell and increased mortality in the three subtropical cities of China. The lag effect structure of the cold spell varied with location and the type of mortality, and evidence of short-term mortality displacement was inconsistent. These findings suggest that extreme cold is an important public health problem in subtropical regions.

Low doses of diagnostic energy X-rays protect against neoplastic transformation in vitro

PURPOSE

To investigate the effect of low doses of 60 kVp X-rays on in vitro transformation frequency.

MATERIALS AND METHODS

HeLa x skin fibroblast human hybrid cells were used to assay transformation from the non-tumorigenic to the tumorigenic phenotype. Subconfluent cultures of cells were exposed to a range of doses of 60 kVp X-rays and seeded for assay of transformation after 24 h post-irradiation holding. Experiments were repeated at least three times and the data pooled for analysis. Transformation frequencies were compared with those of sham-irradiated controls.

RESULTS

At doses < 1 cGy, the observed transformation frequencies were significantly less than those seen in unirradiated cells.

CONCLUSION

Low doses (< 1 cGy) of 60 kVp X-rays protect HeLa x skin fibroblast human hybrid cells against neoplastic transformation in vitro.

The effect of heat waves on mortality and effect modifiers in four communities of Guangdong Province, China

BACKGROUND

Heat waves have been reported to be associated with increased mortality; however, fewer studies have examined the effect modification by heat wave characteristics, individual characteristics and community characteristics.

METHODS

This study investigated the effect of extreme heat on mortality in 2 urban and 2 rural communities in Guangdong Province, China during 2006-2010. The effect of extreme heat was divided into two parts: main effect due to high temperature and added effect due to prolonged heat for several consecutive days. A distributed lag non-linear model was used to calculate the relative risk with consideration of lag days and potential confounding factors. Separate models were further fit by individual characteristics (cause of death, age and gender) and heat wave characteristics (intensity, duration and timing), and potential effect modification of community characteristics was examined using a meta-regression, such as educational levels, percentage of the elderly, Gross Regional Domestic Product (GDP).

RESULTS

The overall main effects (ER=8.2%, 95% CI: 3.4%, 13.2%) were greater than the added effects (ER=0.0%, 95% CI: -3.8%, 4.0%) on the current day. The main effect peaked at lag0-2, and was higher for the two rural areas compared to the two cities, for respiratory compared to cardiovascular mortality, for those ≥75 years old and for females. The modifying effects of heat wave characteristics and community characteristics on mortality were not statistically significant.

CONCLUSION

This study suggests the effects of extreme heat were mainly driven by high temperature, which can be modified by some individual characteristics.

Parity and the metabolic syndrome in older Chinese women: the Guangzhou Biobank Cohort Study

OBJECTIVE

To examine whether parity or gravidity contributes to the development of the metabolic syndrome (MS).

METHODS

The first phase of the Guangzhou Biobank Cohort Study recruited 7352 women and 3065 men aged 50-93 years in 2003-4. Data on the number of live births and pregnancies, other reproduction-associated factors and socioeconomic and lifestyles factors were collected by standardized interview. The MS components were determined through physical examination and measurement of fasting blood samples. MS was identified if waist circumference was >or= 90 cm for men or >or= 80 cm for women, plus any two of: (a) raised triglyceride (TG) level (1.7 mmol/l) or specific treatment for this lipid abnormality; (b) reduced high density lipoprotein (HDL)-cholesterol (< 1.03 mmol/l in males or < 1.29 mmol/l in females) or specific treatment for this lipid abnormality; (c) raised blood pressure (BP, systolic BP >or= 130 mmHg or diastolic BP >or= 85 mmHg) or hypertension therapy; and (d) raised fasting glucose (>or= 5.6 mmol/l) or previously diagnosed type 2 diabetes.

RESULTS

Before adjustment for potential confounders, we found associations between the number of births and lifestyle and socioeconomic factors in both sexes. However, in women, but not in men, body mass index (BMI), waist-hip ratio, triglyceride and glucose were positively associated with the number of birth after adjusting for a range of potential confounders. The age-adjusted prevalence of the MS increased with the number of births and pregnancies in women, but the gradient for birth was steeper than that for pregnancies [odds ratio change per birth 1.16, 95% confidence interval (CI) 1.11-1.22, P < 0.001; odds ratio change per pregnancy 1.11, 95% CI 1.06-1.16, P < 0.001], although attenuating the association adjustment did not affect the significance of these findings. There was no association in men with regard to the number of their partners' live births given the same analysis and similar shared living background with the women.

CONCLUSION

Higher parity or gravidity was associated with a consistent increase in the risk of MS in Chinese women. As the association persisted after adjustment for lifestyle factors and there was no association between the risk of MS and the number of births associated with the partners of the males, the association in women may represent a biological response to pregnancy.

A Global Trend Analysis of Kidney Cancer Incidence and Mortality and Their Associations with Smoking, Alcohol Consumption, and Metabolic Syndrome

BACKGROUND

Kidney cancer is a major urological disease globally, with more than 400 000 new cases diagnosed every year.

OBJECTIVE

To investigate incidence and mortality trends for kidney cancer and their associations with modifiable risk factors for kidney cancer.

DESIGN, SETTING, AND PARTICIPANTS

The most up-to-date figures on kidney cancer incidence and mortality were collected from the GLOBOCAN database and the Cancer Incidence in Five Continents (CI5). Data on total alcohol consumption and the prevalence of smoking, overweight, diabetes, and hypertension were extracted from the World Health Organization Global Health Observatory data repository.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Age-standardized rates (ASRs) for incidence and mortality and their correlations with potential risk factors for kidney cancer were investigated. Multivariable linear regression analysis was also conducted. The 10-yr temporal patterns for incidence are presented as the average annual percent change with 95% confidence interval using joinpoint regression analysis.

RESULTS AND LIMITATIONS

Globally, there is wide variation in kidney cancer incidence and mortality. There were positive correlations between rates of smoking, alcohol consumption, and overweight and ASRs of kidney cancer incidence and mortality. Multivariable regression analysis revealed that alcohol consumption and overweight were significant risk factors for kidney cancer incidence, while smoking and alcohol consumption were significant risk factors for kidney cancer mortality. There was an increasing trend for the incidence of kidney cancer globally, with a particularly prominent trend for European countries. Of note, increasing incidence of kidney cancer is evident even for younger individuals aged <50 yr. However, cancer registries vary by country and period and there is a lack of data regarding the severity of risk factors and disease characteristics such as the distribution of histological groups, tumor grading, and staging.

CONCLUSIONS

There is an increasing trend for kidney cancer incidence globally, particularly in European countries and the younger population. Modifiable risk factors for kidney cancer incidence and mortality have been identified. The increasing incidence of kidney cancer among younger individuals is worrying and warrants early action on possible preventive measures.

PATIENT SUMMARY

The incidence of kidney cancer has been increasing globally, particularly in European countries and the younger population. Risk factors include smoking, alcohol consumption, overweight, and hypertension, and these factors are all modifiable.

Characterization of N-ethyl-N-nitrosourea-induced malignant and benign breast tumors in rats by using three MR contrast agents

A carcinogen (N-ethyl-N-nitrosourea)-induced animal tumor model was established to grow malignant and benign breast tumors. In each tumor the pharmacokinetic characteristics were measured by using three contrast agents, gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA; <1 kD), Gadomer-17 (35 kD), and albumin-Gd-DTPA (70-90 kD). Infiltrating ductal carcinomas (IDC) with low, medium, and high Scarf-Bloom-Richardson grades and fibroadenomas (FA) were analyzed. We found that Gd-DTPA could differentiate between FA and malignant tumors, but not between malignant tumors of low and high grades. In contrast, the intermediate size agent Gadomer-17 could differentiate between high-grade and low-grade IDC, but not between low-grade IDC and FA due to their similar enhancement patterns (despite their different origins). The largest agent, albumin-Gd-DTPA, was capable of differentiating both, but the low contrast-to-noise ratio was its major technical concern. The results in this breast tumor model suggest that macromolecular agents provide useful information for differential diagnosis among IDCs of various grades, but they do not provide superior information than Gd-DTPA for differential diagnosis between IDC and FA.

Disease Burden, Risk Factors, and Recent Trends of Liver Cancer: A Global Country-Level Analysis

BACKGROUND

This study aimed to evaluate the updated disease burden, risk factors, and temporal trends of liver cancer based on age, sex, and country.

METHODS

We estimated the incidence of liver cancer and its attribution to hepatitis B virus (HBV) and hepatitis C virus (HCV) in 2018 based on the Global Cancer Observatory and World Health Organization (WHO) Cancer Causes database. We extracted the prevalence of risk factors from the WHO Global Health Observatory to examine the associations by weighted linear regression. The trend analysis used data from the Cancer Incidence in Five Continents and the WHO mortality database from 48 countries. Temporal patterns of incidence and mortality were calculated using average annual percent change (AAPC) by joinpoint regression analysis.

RESULTS

The global incidence of liver cancer was (age-standardized rate [ASR]) 9.3 per 100,000 population in 2018, and there was an evident disparity in the incidence related to HBV (ASR 0.2-41.2) and HCV (ASR 0.4-43.5). A higher HCV/HBV-related incidence ratio was associated with a higher level of alcohol consumption (β 0.49), overweight (β 0.51), obesity (β 0.64), elevated cholesterol (β 0.70), gross domestic product (β 0.20), and Human Development Index (HDI; β 0.45). An increasing trend in incidence was identified in many countries, especially for male individuals, population aged ≥50 years, and countries with a higher HCV/HBV-related liver cancer incidence ratio. Countries with the most drastic increase in male incidence were reported in India (AAPC 7.70), Ireland (AAPC 5.60), Sweden (AAPC 5.72), the UK (AAPC 5.59), and Norway (AAPC 4.87).

CONCLUSION

We observed an overall increasing trend of liver cancer, especially among male subjects, older individuals, and countries with a higher prevalence of HCV-related liver cancer. More efforts are needed in enhancing lifestyle modifications and accessibility of antiviral treatment for these populations. Future studies should investigate the reasons behind these epidemiological changes.

Lymphocyte DNA damage in cigarette factory workers measured by the Comet assay

To investigate whether there were separate and combined effects of occupational exposure to tobacco dust and smoking on lymphocyte DNA damage, 148 workers from a cigarette manufacturing factory (107 occupationally exposed to tobacco dust from the production department and 41 unexposed controls who were managerial workers) were included in the study. The Tail Moment (TM) of Comet assay was used to measure DNA damage. The two groups had similar mean age, mean duration of work and smoking prevalence. The exposed workers had a larger TM than that of the controls (mean+/-S.D.: 43.43+/-13. 77 vs. 38.89+/-8.98, p<0.05). Smokers had significantly larger TM than non-smokers (47.25+/-14.02 vs. 38.90+/-10.75, p<0.001). Analysis of variance after adjustment for age and gender showed that occupational exposure and smoking had a significant and independent effect on Tail Moment (p=0.025 and p=0.002, respectively) and there was a significant positive two way interaction between the two factors (p=0.019). Age and gender had no significant effect on TM. The present study suggests that smoking and tobacco dust exposure can induce lymphocyte DNA damage and there is a synergistic effect of tobacco dust exposure and smoking on DNA damage.

Snoring and vascular risk factors and disease in a low-risk Chinese population: the Guangzhou Biobank Cohort Study

STUDY OBJECTIVE

Snoring is a common condition, but data describing the relationship between snoring and vascular disease is very limited in Asian populations. We therefore describe the association between snoring and vascular disease and associated risk factors.

DESIGN

Cross-sectional study of baseline data from the Guangzhou Biobank Cohort Study.

SETTING

Community-based elderly association from Guangzhou, China.

PARTICIPANTS

10413 Chinese subjects (50-85 years of age).

MEASUREMENTS

Self-reported snoring status and frequency and frequency of daytime tiredness were collected by questionnaire, as were demographic and socioeconomic data, disease histories, and potential confounders, such as smoking and alcohol consumption. Anthropometry, blood pressure, and fasting glucose and lipid profile were also measured.

RESULTS

Self-reported snoring frequency was identified in 8325 (80.0%) subjects, with 51.6% reporting that they snored, of whom 15.5% were daily snorers. Increasing prevalence of snoring showed a clear positive relationship with cardiovascular risk factors, including age, obesity, blood pressure, and lipid levels (p < .001 for all). The prevalence of self-reported vascular-disease history was low but significantly associated with increasing snoring frequency. Logistic regression showed that snoring frequency was an independent predictor of vascular-disease history (odds ratios [95% confidence intervals] 1.68 [1.32-2.13] for daily snorers compared with the never-snorer reference group), of the metabolic syndrome (2.16 [1.88-2.49]) and each of its components (hypertension [1.37 (1.20-1.56)], and of dyslipidemia [1.22 (1.07-1.40)], central obesity [2.39 (2.08-2.76)], and diabetes [1.30 (1.09-1.56)]) after adjustment for potential confounders.

CONCLUSION

Increasing snoring frequency was associated with an increasing prevalence of risk factors and self-reported vascular disease. Snoring may a useful marker for increased risk of vascular disease.

Height, its components, and cardiovascular risk among older Chinese: a cross-sectional analysis of the Guangzhou Biobank Cohort Study

OBJECTIVES

Better childhood conditions, inferred from height and specifically leg length, are usually protective against ischemic heart disease and its risk factors in Western countries. In other geoethnic populations, height is less clearly protective, casting doubt on there being a biological etiology. To clarify the role of childhood conditions, we examined the associations of height and its components with cardiovascular risk among older Chinese people.

METHODS

We used multivariable regression to examine the associations of height and its components with blood pressure, lipid profile, and diabetes in 10413 older Chinese adults (mean age=64.6 years).

RESULTS

After we adjusted for age, gender, socioeconomic status, and lifestyle habits, greater sitting height was associated with diabetes and dyslipidemia. Longer legs were associated with lower pulse pressure and lower low-density lipoprotein cholesterol.

CONCLUSIONS

We provide indirect anthropometric evidence for the role of pre-pubertal and pubertal exposures on cardiovascular risk. Pubertal exposures are stronger than are prepubertal exposures but may be influenced by osteoporotic decline in old age. Further research should establish whether the observed relations are ethnically specific or relate to the stage or trajectory of socioeconomic development.

Reproducibility and Validity of a Food Frequency Questionnaire for Assessing Dietary Consumption via the Dietary Pattern Method in a Chinese Rural Population

Objective

This study was conducted to assess the reproducibility and validity of a food frequency questionnaire (FFQ) that was developed to assess the overall dietary consumption via dietary pattern method in a rural population in southwest China.

Methods

A total of 179 participants aged between 40 and 70 years old were included in this study. Participants administered FFQ at baseline (FFQ1) and one year later (FFQ2) to assess the reproducibility. Six 3-day 24-hour recalls (24HRs) were completed between the administrations of two FFQs to determine the validity. Dietary patterns from three separate dietary sources were derived by using principle component factor analysis. Comparisons between dietary pattern scores were made by using Pearson or intraclass correlation coefficient, cross-classification analysis, weighted kappa (κ) statistic and Bland-Altman analysis. The de-attenuated method was adopted to correct the monthly and seasonally variation and the partial correlation analysis was used correct the influence by total energy intake.

Results

Two major dietary factors, labeled as prudent pattern and processed food pattern, were identified. The prudent pattern was characterized by higher factor loadings of wheat, rice, fresh vegetables, bean products, nuts, red meat, white meat and fresh eggs; and the processed food pattern was characterized by higher factor loadings of pickled vegetables, preserved vegetables and salted meat. Between Two FFQs, intraclass correlation coefficients were 0.57 for prudent pattern and 0.55 for processed food pattern, partial Pearson correlation coefficients were 0.51 for the prudent pattern and 0.56 for the processed food pattern; weighted κ statistic ranged from 0.45 (for the prudent pattern) to 0.56 (for the processed food pattern). Between FFQs and 24HRs, de-attenuated correlation coefficients ranged from 0.54 to 0.78 for the prudent pattern and from 0.55 to 0.61 for the processed food pattern; partial Pearson correlation coefficients ranged from 0.41 to 0.56 for the prudent pattern and from 0.42 to 0.44 for the processed food pattern; weighted κ statistic ranged from 0.42 to 0.46 for prudent pattern and from 0.43 to 0.60 for processed food pattern. The Bland-Altman plots and limits of agreement indicated that the deviation/divergence was not obvious for both of the patterns between FFQ1 and FFQ2 and between FFQs and 24HRs.

Conclusion

The study suggests that the FFQ is reasonably reproducible and valid to assess the overall dietary consumption via dietary pattern methods in the Chinese rural population.

Spatiotemporal mapping and assessment of daily ground NO2 concentrations in China using high-resolution TROPOMI retrievals

Nitrogen dioxide (NO2) is an important air pollutant that causes direct harms to the environment and human health. Ground NO2 mapping with high spatiotemporal resolution is critical for fine-scale air pollution and environmental health research. We thus developed a spatiotemporal regression kriging model to map daily high-resolution (3-km) ground NO2 concentrations in China using the Tropospheric Monitoring Instrument (TROPOMI) satellite retrievals and geographical covariates. This model combined geographically and temporally weighted regression with spatiotemporal kriging and achieved robust prediction performance with sample-based and site-based cross-validation R2 values of 0.84 and 0.79. The annual mean and standard deviation of ground NO2 concentrations from June 1, 2018 to May 31, 2019 were predicted to be 15.05 ± 7.82 μg/m3, with that in 0.6% of China's area (10% of the population) exceeding the annual air quality standard (40 μg/m3). The ground NO2 concentrations during the coronavirus disease (COVID-19) period (January and February in 2020) was 14% lower than that during the same period in 2019 and the mean population exposure to ground NO2 was reduced by 25%. This study was the first to use TROPOMI retrievals to map fine-scale daily ground NO2 concentrations across all of China. This was also an early application to use the satellite-estimated ground NO2 data to quantify the impact of the COVID-19 pandemic on the air pollution and population exposures. These newly satellite-derived ground NO2 data with high spatiotemporal resolution have value in advancing environmental and health research in China.

Association between whole grain intake and breast cancer risk: a systematic review and meta-analysis of observational studies

Background

Epidemiological studies have found that high whole grain intake may be associated with a reduced risk of breast cancer. However, the evidence has not been consistent. We conducted a meta-analysis to quantitatively assess the association between whole grain intake and breast cancer risk.

Methods

Relevant observational studies were identified by searching PubMed, Embase, Cochrane library databases, and Google Scholar through April 2017. Summary relative risk (RR) estimates were calculated using random-effects meta-analysis.

Results

A total of 11 studies, including 4 cohort and 7 case-control studies and involving 131,151 participants and 11,589 breast cancer cases, were included in the current meta-analysis. The pooled RR of breast cancer for those with high versus low whole grain intake was 0.84 (95% confidence interval [CI]: 0.74 to 0.96, p = 0.009; I² = 63.8%, p_{for heterogeneity} = 0.002). Subgroup analysis by study design found a significant inverse association in the case-control studies (RR: 0.69; 95% CI: 0.56 to 0.87, p = 0.001; I² = 58.2%, p _{for heterogeneity} = 0.026), but not in the cohort studies (RR, 0.96; 95% CI: 0.82 to 1.14, p = 0.69; I² = 66.7%, p for heterogeneity = 0.029). In addition, stratified analysis suggested that sample size could be a potential source of heterogeneity.

Conclusions

Results of the current meta-analysis suggest that high intake of whole grains might be inversely associated with a reduced risk of breast cancer, and the inverse association was only observed in case-control but not cohort studies. More large-scale cohort studies are needed to confirm the inverse association observed.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0394-2) contains supplementary material, which is available to authorized users.

Correlation between genetic variations in Hox clusters and Hirschsprung's disease

Interactions between migrating neural crest cells and the environment of the gut are crucial for the development of the enteric nervous system (ENS). A key signalling mediator is the RET-receptor-tyrosine-kinase which, when defective, causes Hirschprung's disease (HSCR, colon aganglionosis). RET mutations alone cannot account for the variable HSCR phenotype, invoking interactions with as yet unknown, and probably inter-related, loci involved in ENS development. Homeobox (HOX) genes have a major role in gut development as depicted by the enteric Hox code. We investigated whether DNA alterations in HOX genes, either alone or in combination with RET, are implicated in HSCR. Genotyping effort was minimized by applying the HapMap data on Han Chinese from Beijing (CHB). 194 HSCR patients and 168 controls were genotyped using Sequenom technology for 72 tag, single nucleotide polymorphisms (SNPs) distributed along the HOX clusters. The HapMap frequencies were compared to those in our population and standard statistics were used for frequency comparisons. The multifactor-dimensionality-reduction method was used for multilocus analysis, in which RET promoter SNP genotypes were included. Genetic interactions were found between two HOX loci (5'-HOXA13 and 3'UTR-HOXB7) and the RET loci tested. Minor allele frequencies (MAF) of the SNPs tested in our sample were not significantly different from those reported by HapMap when the sample sizes of the populations compared were considered. This is the first evaluation of the HOX genes in HSCR and the first application of HapMap data in a Chinese population. The interacting HOX loci may affect the penetrance of the RET risk allele. HapMap data for the CHB population correlated well with the general Chinese population.

Sporophytic self-incompatibility genes and mating system variation in Arabis alpina

BACKGROUND AND AIMS

Sporophytic self-incompatibility (SI) prevents inbreeding in many members of the Brassicaceae, and has been well documented in a variety of high-profile species. Arabis alpina is currently being developed as a model system for studying the ecological genetics of arctic-alpine environments, and is the focus of numerous studies on population structure and alpine phylogeography. Although it is highly inbreeding throughout most of its range, populations in central Italy have been identified that show inbreeding coefficients (F(IS)) more typical of self-incompatible relatives. The purpose of this study was to establish whether this variation is due to a functioning SI system.

METHODS

Outcrossing rate estimates were calculated based on 16 allozyme loci and self-compatibility assessed based on controlled pollinations for six Italian populations that have previously been shown to vary in F(IS) values. Putative SRK alleles (the gene controlling the female component of SI in other Brassicaceae) amplified from A. alpina were compared with those published for other species. Linkage of putative SRK alleles and SI phenotypes was assessed using a diallel cross.

KEY RESULTS

Functional avoidance of inbreeding is demonstrated in three populations of A. alpina, corresponding with previous F(IS) values. The presence is described of 15 putative SRK-like alleles, which show high sequence identity to known alleles from Brassica and Arabidopsis and the high levels of synonymous and nonsynonymous variation typical of genes under balancing selection. Also, orthologues of two other members of the S-receptor kinase gene family, Aly8 (ARK3) and Aly9 (AtS1) are identified. Further to this, co-segregation between some of the putative S-alleles and compatibility phenotypes was demonstrated using a full-sibling cross design.

CONCLUSIONS

The results strongly suggest that, as with other species in the Brassicaceae, A. alpina has a sporophytic SI system but shows variation in the strength of SI within and between populations.

Is leg length a biomarker of childhood conditions in older Chinese women? The Guangzhou Biobank Cohort Study

OBJECTIVE

In developed western populations longer legs have been shown to be a biomarker of better early childhood conditions. It was hypothesised that in transitioning populations better childhood conditions may bring forward puberty and thus decrease leg length, counteracting the overall positive effect of a favourable childhood environment on leg growth.

DESIGN

Structural equation modelling was used to assess the interrelationship of age, education, father's job, age of menarche and leg length in a cross-sectional sample of 7273 Chinese women aged at least 50 years from the Guangzhou Biobank Cohort Study.

RESULTS

Leg length had no significant association with education or father's occupation on bivariable testing. After including age of menarche in the model, education was associated with longer legs (0.45 cm longer per 10 years of education, 95% CI 0.20 to 0.71). Education was also associated with younger age of menarche (1.21 years younger per 10 years of education, 95% CI 1.09 to 1.34), which was in turn associated with shorter legs (0.23 cm shorter per year of menarche earlier, 95% CI 0.18 to 0.27).

CONCLUSIONS

In older Chinese women leg length is not a universal biomarker of childhood conditions, when proxied by her educational level and father's occupation. Nutritionally driven epigenetic influences operating over generations may constrain growth in very recently developed populations. Given the impact of childhood conditions on health, and the dearth of long-term records outside the industrialised world, a greater understanding of the influences on growth in the developing world is required.

Dietary patterns and the risk of esophageal squamous cell carcinoma: A population-based case-control study in a rural population

BACKGROUND & AIMS

Few studies were available in exploring the roles of dietary patterns in the development of esophageal cancer, especially in China. This study aimed to investigate the roles of dietary patterns in the risk of esophageal squamous cell carcinoma (ESCC) in a Chinese rural population.

METHODS

A population-based cases-control study was designed and conducted in Yanting County, Sichuan Province of China during two years (between June 2011 and May 2013). A total of 942 pairs of ESCC cases and controls were recruited. A food frequency questionnaire was adopted to collect information of dietary consumption. Dietary patterns were extracted by using principle component and factor analysis based on 24 dietary groups. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated by using logistic regression model, with adjustment for possible confounding variables.

RESULTS

Four major dietary patterns were identified, which were labeled as "prudent", "vegetable and fruits", "processed food" and "alcohol drinking". In comparison of the highest with the lowest quartiles of pattern scores, the processed food pattern (OR: 2.84, 95% CI: 2.13-3.80) and alcohol drinking pattern (OR: 2.69, 95% CI: 1.95-3.71) were significantly associated with an increased risk of ESCC, while the vegetable and fruit pattern (OR: 0.70, 95% CI: 0.53-0.92) was associated with reduced risk by 30%. The prudent pattern was associated with a reduced risk by 33% (OR: 0.67, 95% CI: 0.50-0.88) in a multivariate logistic regression model, but no statistical significance was reached in a composite model.

CONCLUSIONS

The results suggest an important role of dietary patterns in ESCC. Diets rich in vegetables and fruits may decrease the risk of ESCC, whereas diets rich in processed food and drinking alcohol may increase the risk.

A comparison of the quality of hypertension management in primary care between Shanghai and Shenzhen: a cohort study of 3196 patients

Strong primary care is in urgent need for the management and control of hypertension. This study aimed to compare the quality of hypertensive care delivered by community health centers (CHCs) in Shanghai and Shenzhen. Multistage random sampling method was used to select 4 CHCs in each city as study settings. A cohort of hypertensive patients under the hypertensive management program in the CHCs was selected from the electronic information system by using a systematic random sampling method. Binary logistic regression models were constructed for comparison between the 2 cities. A total of 3196 patients' records were assessed. The proportions of hypertensive patients who received advice on smoking cessation (33.8 vs 7.7%, P < 0.001), increasing physical activity (52.4 vs 16.8%, P < 0.001), low-sodium diet (72.0 vs 64.1%, P < 0.001), and regular follow-up (37.8 vs 8.6%, P < 0.001) were higher in Shenzhen than in Shanghai. However, the drug treatment rate in Shenzhen was lower than that in Shanghai (74.2 vs 95.2%, P < 0.001). The hypertension control rate in Shenzhen was lower than that in Shanghai (76.3 vs 83.2%, P < 0.001). Better performance in the process of hypertensive care in terms of increasing physical activity advice, low-sodium diet advice, regular follow-up, and drug prescription was associated with a higher rate of hypertension control. The study indicates that primary care is effective in managing hypertension irrespective of management and operation models of CHCs in urban China. Our study suggests that improvements in the process of hypertensive care may lead to better hypertension control.

Association of the metabolic syndrome with vascular disease in an older Chinese population: Guangzhou Biobank Cohort Study

OBJECTIVE

To assess the prevalence of the metabolic syndrome (MS) and relative associations with vascular disease in an older Chinese population using the US National Cholesterol Education Program: Adult Treatment Panel (NCEP: ATP III) and International Diabetes Federation (IDF) definitions.

DESIGN

Cross-sectional study.

SUBJECTS

A total of 3035 men and 7291 women aged 50 to 85 yr recruited from Guangzhou, China.

MEASUREMENTS

All participants received a full medical check-up including measurement of blood pressure, obesity indices, fasting total, LDL-, HDL-cholesterol, triglycerides (TG) and glucose levels. Demographic information and self-reported history of physician-diagnosed coronary heart disease (CHD), stroke and myocardial infarction (MI) were collected through standardized interview.

RESULTS

The estimates under the two definitions differed substantially, with the age standardized prevalence of MS 15.57% using the NCEP: ATP III definition and 25.81% using the IDF definition. Among all participants, 80.23% were similarly classified using both definitions. The association between self-reported CHD, stroke and MI and the MS defined by the IDF definition was stronger than that by the NCEP: ATP III.

CONCLUSIONS

The IDF compared to the ATP III definition shows a stronger association with the MS and associated vascular disease in Chinese. The prevalence of the MS is alarmingly high in this older Chinese population. Comprehensive strategies are needed for prevention and treatment of the MS to reduce the increased societal burden of cardiovascular disease in China.

The impact of particulate matter air pollution (PM2.5) on atherosclerosis in modernizing China: a report from the CATHAY study

BACKGROUND

Air pollution has been associated with an increase in cardiovascular diseases incidence. To evaluate whether air pollution can accelerate atherogenic processes, we assessed the effects of air pollution on important surrogate markers of atherosclerosis [brachial flow-mediated dilation (FMD) and carotid intima-media thickness (IMT)].

METHODS

A total of 1656 Han Chinese (mean age 46.0 + 11.2 years; male 47%) in Hong Kong, Macau, Pun Yu, Yu County and the 3-Gorges Territories (Yangtze River) were studied between 1996 and 2007 [Chinese Atherosclerosis in the Aged and Young Project (the CATHAY Study)]. Cardiovascular risk profiles were evaluated. Particulate matter with an aerodynamic diameter <2.5 µm (PM2.5) parameters were computed from satellite sensors. Brachial FMD and carotid IMT were measured by ultrasound.

RESULTS

Health parameters [age, gender, body mass index, waist : hip ratio (WHR) and glucose)] were similar in lowest and highest PM2.5 exposure tertiles, systolic and diastolic blood pressures and triglycerides were higher (P < 0.001) and low-density cholesterol (LDL-C) was lower in the top PM2.5 tertile (P < 0.001). Brachial FMD [7.84 ± 1.77, 95% confidence interval (CI) 7.59-8.10%, vs 8.50 ± 2.52, 95% CI 8.23-8.77%, P < 0.0001) was significantly lower and carotid IMT (0.68 ± 0.13 mm, 95% CI 0.67-0.69 mm vs 0.63 mm ± 0.15 mm 95% CI 0.62-0.64 mm; P < 0.0001) was significantly thicker in the top PM2.5 tertile compared with the lowest tertile. On multiple regression, FMD was inversely related to PM2.5 (beta = 0.134, P = 0.015) independent of gender, age and blood pressure (model R2 = 0.156, F-value = 7.6, P < 0.0001). Carotid IMT was significantly correlated with PM2.5 exposure (beta = 0.381, P < 0.0001) independent of age, location, gender, WHR, blood pressure and LDL-C (model R2 = 0.408, F-value = 51.4, P-value <0.0001).

CONCLUSIONS

Air pollution is strongly associated with markers of early atherosclerosis, suggesting a potential target for preventive intervention.

c-Reactive protein and the metabolic syndrome in older Chinese: Guangzhou Biobank Cohort Study

OBJECTIVE

To examine the association between serum c-reactive protein (CRP) concentration and the metabolic syndrome (MS) using the International Diabetes Federation Metabolic Syndrome Guidelines (April, 2005) definition in an older Chinese population.

METHODS

Three thousand and fourteen men and 7275 women aged 50-85 years were recruited and received a full medical check-up including measurement of blood pressure, obesity indices, fasting total, LDL-, HDL-cholesterol, triglycerides, glucose and c-reactive protein. Data describing socioeconomic and lifestyle factors was also collected.

RESULTS

Vascular risk factors including waist circumference, weight gain and waist gain since the age of 18, body mass index, waist-hip-ratio, triglyceride, HDL-cholesterol, and systolic and diastolic blood pressures were positively associated with CRP in both men and women (p from <0.001 to 0.016). Compared to those without MS components, adjusted odds ratios for having elevated CRP increased in those with the MS or its components compared those without MS or components (all p<0.001), except for the low HDL-cholesterol in both genders and raised fasting glucose in men. Similarly, the risk of elevated CRP increased with escalating MS components even after adjustment of a range of potential confounders.

CONCLUSIONS

There is a strong relationship between CRP and the constellation of MS components and associated vascular risk in this older Chinese population.