Association between whole blood essential trace elements and cognitive function in older adults.

BACKGROUND: Essential trace elements (ETEs) are essential nutrients for keeping the nervous system functioning. Associations between ETEs and cognitive function are still inconclusive and limited. OBJECTIVES: We aimed to investigate the individual and joint associations between ETEs and cognitive function among older adults. METHODS: A population (N = 2181) at an average age≥ 65 from Yiwu cohort in China was available for this study. Whole blood chromium (Cr), selenium (Se), manganese (Mn), and copper (Cu) concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). Cognitive function was assessed using the Mini-Mental State Examination (MMSE), consisting of five specific cognitive domains: orientation, registry, attention and calculation, recall, and language and praxis. Linear regression, restricted cubic spline (RCS) analysis, and Bayesian kernel machine regression (BKMR) were used to analyze the individual and joint associations between ETEs and cognitive function. RESULTS: The association between Cr and MMSE score presented an inverted-U shape (Q3 versus Q1: ß = 0.774, 95 % CI: 0.297, 1.250; Q4 versus Q1: ß = 0.481, 95 % CI: 0.006, 0.956); and Cr was especially associated with the registry, recall, and language and praxis. Per IQR (36.32 µg/L) increase of Se was positively associated with the MMSE score (ß = 0.497, 95 % CI: 0.277, 0.717) and all five cognitive domains. The BKMR showed that the dose-response association between Se and cognitive function increased initially and then decreased with increasing Se concentration when fixed the other ETEs in median. ETEs mixture was positively associated with cognitive function, and Se (posterior inclusion probabilities, PIPs = 0.915) was the most important contributor within the ETEs mixture. CONCLUSIONS: The nonlinear association between Cr and cognitive function suggested further exploration of an appropriate concentration range for ETEs. A positive association between mixed ETEs and cognitive function is a reminder that their joint association should be considered. Further prospective studies or intervention studies are warranted to validate our findings in the future.

HDL-C, longitudinal change and risk of mortality in a Chinese cohort study.

BACKGROUND AND AIMS: High-density lipoprotein cholesterol (HDL-C) concentration and variability are both important factors of cardiovascular disease (CVD) and mortality. We aimed to explore the associations of HDL-C and longitudinal change in HDL-C with risk of mortality. METHODS AND RESULTS: We recruited a total of 69,163 participants aged ≥40 years and had medical examination records of HDL-C during 2010-2014 from the Yinzhou District, Ningbo, China. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression models. We observed a non-linear association of HDL-C with risks of non-accidental and CVD mortality. Compared with the moderate concentration group (1.4-1.6 mmol/L), HDL-C <1 mmol/L was associated with a higher risk of non-accidental mortality (HR: 1.13 (95% CI: 1.01-1.27)) and both HDL-C <1 mmol/L and ≥2 mmol/L were associated with a higher risk of CVD mortality (HRs: 1.23 (95% CI: 1.01-1.50) and 1.37 (95% CI: 1.03-1.82), respectively). Compared with the stable group ([-0.1, +0.1 mmol/L]), a large decrease ([-0.5, -0.3 mmol/L]) and very large decrease (<-0.5 mmol/L) in HDL-C were associated with a higher risk of non-accidental mortality (HRs: 1.40 (95% CI: 1.21-1.63) and 1.78 (95% CI: 1.44-2.20), respectively). Similar results were observed for CVD mortality and cancer mortality. CONCLUSION: Extremely low or high HDL-C and a large decrease or very large decrease in HDL-C were associated with a higher risk of cause-specific mortality. Monitoring of HDL-C may have utility in identifying individuals at higher risk of mortality.

Effect of COVID-19 on hospital visits in Ningbo, China: an interrupted time-series analysis.

OBJECTIVE: Unprecedented rigorous public health measures were implemented during the coronavirus disease 2019 (COVID-19) epidemic, but it is still unclear how the intervention influenced hospital visits for different types of diseases. We aimed to evaluate the impact of the intervention on hospital visits in Yinzhou District, Ningbo, Zhejiang province, China. METHODS: We conducted an interrupted time-series analysis from 1 January 2017 to 6 September 2020 based on the Yinzhou Health Information System in Ningbo, Zhejiang province. The beginning of the intervention was on 23 January 2020, and thus, there were 160 weeks before the intervention and 32 weeks after the implementation of the intervention. Level changes between expected and observed hospital visits in the post-intervention period were estimated using quasi-Poisson regression models. RESULTS: Compared with the expected level, there was an estimated decrease of -22.60% (95% confidence interval (CI): -27.53%, -17.36%) in the observed total hospital visits following the intervention. Observed hospital visits for diseases of the respiratory system were found to be decreased dramatically (-62.25%; 95% CI: -65.62%, -58.60%). However, observed hospital visits for certain diseases were estimated to be increased, including diseases of the nervous system (+11.17%; 95% CI: +3.21%, +19.74%); diseases of pregnancy, childbirth and the puerperium (+27.01%; 95% CI: +17.89%, +36.85%); certain conditions originating in the perinatal period (+45.05%; 95% CI: +30.24%, +61.56%); and congenital malformation deformations and chromosomal abnormalities (+35.50%; 95% CI: +21.24%, +51.45%). CONCLUSIONS: Our findings provided scientific evidence that cause-specific hospital visits evolve differently following the intervention during the COVID-19 epidemic.

Regression-based normative data for social health scale for the elderly (short version) in eastern China.

BACKGROUNDS: Social Health Scale for the Elderly short version (SHSE-S) is a psychometrically sound instrument that comprehensively assesses the social health status of older adults in China. The aim of the present study was to establish continuous normative data of SHSE-S. METHODS: We conducted a multicenter cross-sectional study among 31 communities in eastern China. Older adults aged 60 years and above were invited to participate in the study. Each participant was interviewed in-person to finish a structured questionnaire. The SHES-S score was calculated and standardized for each participant. We split the sample into generation and validation datasets and compared the distribution of SHSE-S score between two datasets. Multivariable linear regression was used to assess the SHSE-S score and demographic variables. Regression-based norms were built using a four-step process. RESULTS: A total of 6089 participants (51.2% females) aged 60 years old and above (mean age = 71.3, SD = 8.0) were enrolled as the normative sample. No significant difference was found between the distribution of SHSE-S standardized score in the generation (N = 2392) and validation (N = 3697) datasets. Multivariable linear regression showed that females, higher education levels were positive indicators while aging, living alone, divorced or never married, multimorbidity were negative factors. The regression-based norm which taking demographic factors into account was established and a user-friendly worksheet was also provided to facilitate the scoring and norming of the SHSE-S. CONCLUSIONS: The population-based regression norm of SHSE-S can be a useful tool for assessing the social health status of the Chinese elderly population.

[Association between H-ras and L-myc gene polymorphisms and susceptibility to colorectal cancer].

OBJECTIVE: To explore the association between the polymorphisms of oncogenes H-ras and L-myc and colorectal cancer risk, and the interaction of those genes. METHODS: The genotypes of H-ras and L-myc genes were determined by polymerase chain reaction-based restriction fragment length polymorphism analysis. Stratified analysis and logistic model were used to detect the gene-gene interaction. The gene-gene interaction was validated by multifactor dimensionality reduction (MDR) analysis. RESULTS: The single SNP model showed that the polymorphisms of H-ras and L-myc genes were not significantly related with colorectal cancer risk (P > 0.05). Stratified analysis revealed that among the L-myc LS + SS genotype carriers, those with H-ras TC + CC genotype showed significantly increased risk of rectal cancer than those with TT genotype (OR = 1.81, P = 0.005). The positive interaction between L-myc and H-ras was detected by logistic regression model. The OR of the interaction effect was 2.74 (P = 0.024). This result was confirmed in the MDR model, with 54.83% testing balanced accuracy and 10/10 cross-validation consistency, and the model was still significant after the 1000 times permutation test (P = 0.001). CONCLUSION: Our findings suggest that the polymorphism of H-ras and L-myc genes is not related to colorectal cancer risk, but there is a synergy between H-ras and L-myc polymorphisms in the development of rectal cancer.

[Association of CASP3 and CASP9 polymorphisms with genetic susceptibility to stomach cancer].

OBJECTIVE: To investigate the association between the apoptosis genes CASP3(rs12108497) and CASP9 (rs4646018) polymorphisms and the risk of developing stomach cancer. METHODS: In this population-based case-controlstudy, 278 cases with stomach cancer and 278 age (± 5 years), gender, and residential area matched controls were recruited. The genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The unconditional Logistic regression analysis was utilized to calculate the odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The individuals with TC, CC genotypes of rs12108497 locus had significantly increased risk of stomach cancer in comparison to those carrying TT genotype (OR= 1.45, 95% CI: 1.01-2.07 for TC; OR= 2.17, 95%CI: 1.15-4.08 for CC). However, the rs4646018 locus of CASP9 gene polymorphism was not related to stomach cancer risk. Compared with the subjects carrying the both low-risk genotypes, those carrying 1 or 2 high-risk genotypes had a noteworthy increased risk of stomach cancer (OR= 1.60, 95% CI: 1.12-2.30). The combined high-risk genotypes appeared to be more evident in subjects of male (OR= 1.62, 95% CI: 1.05-2.49), ever-smokers (OR= 1.87, 95%CI: 1.12-3.12), ever-drinkers (OR= 1.92, 95%CI: 1.02-3.65) and no family history of cancer (OR= 1.78, 95%CI: 1.18-2.68). CONCLUSION: The current findings suggest that the polymorphism of CASP3 rs12108497 might be associated with the risk of stomach cancer. However, the CASP9 rs4646018 polymorphism may not be related to the stomach cancer risk.

[Association of CASP3 polymorphisms and its haplotypes with susceptibility of breast cancer].

OBJECTIVE: To investigate the association of Caspase3 (CASP3) polymorphisms with susceptibility of breast cancer in Chinese Han population. METHODS: In this population-based case-control study, 251 cases with breast cancers and 251 matched controls in terms of habitation and age (±5 years) were recruited. Rs4647693, rs2696056, rs4647610 were selected as TagSNPs in CASP3 gene and genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The haplotype distribution was estimated and compared by PHASE software. RESULT: There was significant association between menarche age and breast cancer (P=0.007), as well as the early pregnancy age and breast cancer (P=0.002). No significant differences were detected in the distribution of CASP3 genotype and haplotype frequencies between breast cancer patients and controls. The GGA was the most common haplotype both in cases and controls. CONCLUSION: CASP3 polymorphisms and its haplotypes were not related to the susceptibility of breast cancer.

[Expression of caspase apoptosis pathway genes mRNA in colorectal cancer and polyps].

OBJECTIVE: To investigate mRNA expression of caspase apoptosis pathway genes in colorectal cancer, polyps and normal mucosa. METHODS: Nineteen patients with colorectal cancer, 86 patients with polyps and 10 normal controls were enrolled from 2008 to 2010. Fluorescence quantitative RT-PCR was performed to detect the mRNA expression of caspase apoptosis pathway genes (caspase-2,-3,-6,-7,-8,-9 and -10) in colorectal cancer, polyps and normal mucosa. RESULT: There were no statistically significant differences of demographic characteristics between patients with colorectal cancer, patients with polyps and normal controls. Compared with normal control group, the mRNA expression of all selected genes except for caspase-3 were lower; however, the P values did not reach statistic significance. Highly positive correlations were observed between mRNA expression of all selected genes except caspase-9. CONCLUSION: There are no significant changes in mRNA expression levels of caspase apoptosis pathway genes from normal mucosa to polyps to cancer. The mRNA expressions of most caspase pathway genes are highly correlated with each other.

[Association of miR-605 and miR-149 genetic polymorphisms with related risk factors of lung cancer susceptibility].

OBJECTIVE: To explore association of miR-149 and miR-605 polymorphisms with other risk factors of lung cancer susceptibility among Chinese population. METHODS: Two hundred and forty-four patients with lung cancer and 243 cancer-free controls matched by age and sex were enrolled from 2002 to 2008. Peripheral venous blood samples were collected from all subjects. Single nucleotide polymorphisms (SNPs) of miR-149 and miR-605 were genotyped by PCR-RFLP. Multiple-variable logistic regression model was used to assess the association of SNPs and cancer related risk factors for lung cancer. RESULT: There was not significant association of SNPs of miR-149 and miR-605 with lung cancer. A marginal significance was observed while the males with at least one G allele of miR-605 had higher risk of lung cancer (OR=1.5, 95% CI:1.0-2.3) than those with AA genotype. Increased frequency of smoking was associated with lung cancer risk. Compared with no-smoker, the subjects with <20 and >20 cigarettes/day had higher risk of lung cancer: OR (95%CI)=1.7(1.0-3.0) for <20 cigarettes, OR (95%CI)=4.2(2.3-7.6) for >20 cigarettes. There was no interaction between two genes and smoking on lung cancer. CONCLUSION: miR-149 polymorphisms may not affect lung cancer susceptibility. miR-605 gene mutant might be increase the risk of lung cancer among males. Cigarette smoking increased a risk of lung cancer, but there were not interactive effects between two gene and smoking on lung cancer.

Low LDL-C levels are associated with risk of mortality in a Chinese cohort study.

BACKGROUND AND AIMS: Although low-density lipoprotein cholesterol (LDL-C) has been considered as a risk factor of atherosclerotic cardiovascular disease, limited studies can be available to evaluate the association of LDL-C with risk of mortality in the general population. This study aimed to examine the association of LDL-C level with risk of mortality using a propensity-score weighting method in a Chinese population, based on the health examination data. METHODS: We performed a retrospective cohort study with 65,517 participants aged 40 years or older in Ningbo city, Zhejiang. LDL-C levels were categorized as five groups according to the Chinese dyslipidemia guidelines in adults. To minimize potential biases resulting from a complex array of covariates, we implemented a generalized boosted model to generate propensity-score weights on covariates. Then, we used Cox proportional hazard regression models with all-cause and cause-specific mortality as the dependent variables to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs). RESULTS: During the 439,186.5 person years of follow-up, 2403 deaths occurred. Compared with the median LDL-C group (100-130 mg/dL), subjects with extremely low LDL-C levels (group 1) had a higher risk of deaths from all-cause (HR = 2.53, 95% CI:1.80-3.53), CVD (HR = 1.84, 95% CI: 1.28-2.61), ischemic stroke (HR = 2.29, 95% CI:1.32-3.94), hemorrhagic stroke (HR = 3.49, 95% CI: 1.57-7.85), and cancer (HR = 2.12, 95% CI: 1.04-4.31) while the corresponding HRs in LDL-C group 2 were relatively lower than that in group 1. CONCLUSIONS: Low LDL-C levels were associated with an increased risk of all-cause, CVD, ischemic stroke, hemorrhagic stroke, and cancer mortality in the Chinese population.

Short-term associations between ambient fine particulate matter pollution and hospital visits for chronic obstructive pulmonary disease in Yinzhou District, China.

Ambient particulate matter is one of the main risk factors of chronic obstructive pulmonary disease (COPD) in developing countries. However, the studies were scant in China concerning the health effects of the fine particulate matter (PM2.5; particulate matter ≤ 2.5 µm in diameter) on hospital visits for COPD. We applied a generalized additive model (GAM) to calculate relative risks (RRs) with 95% confidence intervals (CIs) for the associations between hospital visits for COPD and an interquartile range (24.50 µg/m3) increment of ambient PM2.5 concentrations in Yinzhou District between 2016 and 2018. The ambient PM2.5 concentration was positively associated with hospital visits for COPD at a distributed lag of 0-7 days (RR = 1.073, 95% CI, 1.016, 1.133). In the stratified analysis, we found that the association between ambient PM2.5 and COPD was stronger during the warm season (April to September) than that during the cold season (October to March), but we did not observe statistically significant differences in age groups (< 60 years and ≥ 60 years) or gender groups (male and female) related to the effects of PM2.5. The associations between ambient PM2.5 and COPD became partially attenuated after the adjustment for gaseous pollutants in subgroups. Our findings could provide evidence that regulations for controlling both PM2.5 and gaseous pollutants should be implemented to protect the overall population.

[Association between HRE-2 gene polymorphism at codon 655 and genetic susceptibility of colorectal cancer].

OBJECTIVE: To explore the distribution of HER-2 genetic polymorphism at codon 655 and its association with susceptibility of colorectal cancer in Chinese. METHODS: A population-based case-control study was carried out. 292 patients with colorectal cancer and 842 healthy controls were interviewed. Meanwhile, the genetic polymorphism of HRE-2 was detected using polymerase chain reaction-restriction fragment length polymorphism. RESULTS: The frequencies of Ile/Val+Val/Val genotypes and Val allele were both higher in cases (25.34% and 13.36%) than those in controls (18.41% and 9.74%) (P<0.05). Compared with Ile/Ile genotype, Ile/Val+Val/Val genotypes were significantly associated with colorectal cancer [ORadjusted=1.54, 95% CI: 1.11-2.14]. The adjusted odds ratio of interactions between this polymorphism and smoking, alcohol drinking were 1.43 (95%CI: 0.88-2.30) and 1.29 (95%CI: 0.73-2.29), respectively. CONCLUSION: The present findings suggest that HER-2 genetic polymorphism at codon 655 may be associated with the risk of colorectal cancer in Chinese. In addition, there are no interactions between this polymorphism and smoking, alcohol drinking, respectively.

Association between CPR-related genetic variants and risk of ischemic stroke: a nested case-control study.

Background: Serum C-reactive protein (CRP) has been reported to be associated with risk of ischemic vascular disease including ischemic stroke. Genome-wide association studies have revealed several gene variants related to CRP concentration. Methods: We investigated genetic variants in CRP-related genes associated with ischemic stroke in a nested case-control study with 138 ischemic stroke cases and 276 controls. We sequenced the whole coding region of six CPR-related genes and selected eligible SNPs. Three genetic models (additive, dominant and recessive) were calculated by a multivariable conditional logistic regression to estimate the association between SNPs and risk of ischemic stroke. We also calculated gene-environment interactions by using a crossover analysis. Results: Three out of 10 eligible SNPs were shown to be associated with risk of ischemic stroke. rs1800947 in CRP gene (additive model: OR = 2.08, 95% CI: 1.00-4.23) and rs1169288 in HNF1A gene (additive model: OR = 1.45, 95% CI: 1.03-2.06) were associated with an increased risk of ischemic stroke. rs440446 in APOE gene (additive model: OR = 0.63, 95%CI: 0.44-0.88) was associated with a decreased risk of ischemic stroke. Genetic risk scores models including SC-GRS and OR-GRS both showed a significant association with risk of ischemic stroke. These three SNPs interacted with smoking and red meat intake. Conclusions: Our study showed genetic variants of CRP-related genes were associated with risk of ischemic stroke. Our findings could provide useful data for the etiology of ischemic stroke.

Association of Visit-to-Visit Variability of Blood Pressure with Cardiovascular Disease among Type 2 Diabetes Mellitus Patients: A Cohort Study.

BACKGROUND: Increasing evidence has shown that visit-to-visit variability (VVV) of blood pressure (BP) is associated with an increased risk of cardiovascular disease (CVD). The objective of this study was to evaluate the impact of VVV of systolic blood pressure (SBP) and diastolic blood pressure (DBP) on the risk of CVD among patients with type 2 diabetes mellitus (T2DM) in China. METHODS: We conducted a retrospective cohort study of 10,163 T2DM patients who were not previously diagnosed with CVD from January 2008 to December 2012 in Ningbo, China. The VVV of BP was calculated using five metrics, including standard deviation (SD), coefficient of variation (CV), variation independent of mean, average real variability, and successive variability (SV) of measurements, obtained over a 24-month measurement period. Hazard ratios and 95% confidence intervals (CIs) were estimated by Cox proportional hazards regression models for the associations of variability in BP with risk of CVD. RESULTS: A total of 894 CVD events were observed during a median follow-up of 49.5 months. The hazard ratio in the highest quintile of SD of SBP was 1.24 (95% CI, 1.01 to 1.52) compared with patients in the lowest quintile. The association between higher VVV of DBP and risk of CVD was not consistent across different metrics and sensitivity analyses. CONCLUSION: Higher VVV of SBP was associated with an increased risk of CVD, irrespective of the mean SBP level. Future studies are needed to confirm these findings.

Effects of air pollution on hospital visits for pneumonia in children: a two-year analysis from China.

Although the effect of air pollution on respiratory health has been identified, few studies can be available to evaluate the association of air pollution with hospital visits for children's pneumonia in China. To explore whether high concentrations of air pollutants (including PM2.5, PM10, NO2, and SO2) are related to hospital visits for pneumonia in children, we conducted a population-based time-series study in Ningbo, China, from January 1st, 2014 to November 1st, 2015. We used a generalized additive Poisson regression model to calculate risk ratios and 95% confidence intervals for the associations of air pollutants and hospital visits for pneumonia in children and found that these four pollutants were associated with the increased hospital visits for pneumonia in children (1.3% for PM2.5, 1.0% for PM10, 2.9% for NO2, 5.0% for SO2 per 10-µg/m3 increase in PM2.5, PM10, NO2, and SO2, respectively). Stronger associations were observed in the cold seasons and among children under 5 years.

Association between short-term exposure to ambient air pollution and daily mortality: a time-series study in Eastern China.

Few studies were conducted to evaluate health effects of acute exposure to PM2.5 and daily mortality in Asian countries due to lack of large-scale PM2.5 monitoring data. We conducted a time-series study to examine the associations of short-term exposure to four common air pollutants (PM2.5, PM10, NO2, and SO2) and daily mortality in Ningbo, Zhejiang, China. We used generalized addictive model (GAM) to estimate relative risks (RRs) and 95% confidence intervals (CIs) for the association of these four air pollutants with daily mortality. The study included 9365 people in the 2-year study period from 2014 to 2015. SO2 were significantly associated with risk of NAD, RD, and CD mortality with RRs of 1.034 (95% CI 1.004, 1.064), 1.067 (95% CI 1.010, 1.127), and 1.049 (95% CI 1.001, 1.098), respectively.PM2.5 and PM10 were significantly associated with risk of death from NAD mortality in warm season. Similar associations were observed for PM10 (RR = 1.056, 95% CI 1.004, 1.111) and risk of CD mortality. The study provides further evidence that short-term exposure to PM2.5, PM10, NO2, and SO2 are associated with increased risk of daily mortality.

Acute effect of fine and coarse particular matter on cardiovascular visits in Ningbo, China.

Although a growing number of epidemiological studies have been conducted on size-specific health effects of particulate matter in China, results remain inconsistent. In this study, we investigated acute effect of fine and coarse particular matter on cardiovascular hospital visits in Ningbo, China. We used generalized additive models to examine short-term effects of PM2.5 and PM10-2.5 on cardiovascular hospital visits by adjustment for temporal, seasonal, and meteorological effects. Subgroup analyses were conducted by age, sex, and season. We also examined the stability of their effects in multi-pollutant models. We found that PM2.5 were associated with cardiovascular hospital visits (RR = 1.006; 95% CI 1.000, 1.011) and results remained similar after adjustment for PM10-2.5 (RR = 1.005; 95% CI 0.998, 1.013). There was a borderline association between PM10-2.5 and cardiovascular hospital visits (RR = 1.007; 95% CI 0.997, 1.016), which disappeared after controlling for PM2.5 (RR = 1.000; 95% CI 0.988, 1.013). The associations appeared to be stronger in the cold season and among the elderly (≥ 75 years). The findings of this study suggested significant adverse effects of PM2.5, but no independent effects of PM10-2.5 on cardiovascular hospital visits. Additional studies are needed to confirm these findings.

[Association of p53 polymorphisms and its haplotypes with susceptibility of breast cancer].

OBJECTIVE: To investigate the association of p53 polymorphisms with susceptibility to breast cancer in Chinese Han population. METHODS: In this population-based case-control study, 84 cases with breast cancers and 168 controls, matched to the cases in terms of gender, habitation and age (5 years), were genotyped for codon 72, intron 3, and intron 6 polymorphisms in p53 gene by polymerase chain reaction-restriction-fragment length polymorphism (PCR-RFLP) methods. The haplotype distribution was estimated and compared by EH linkage software 1. 2. RESULTS: The distributions of age, alcohol drinking, family history of cancer in first and second relatives were not significantly different between cases and controls. There was significant association between cigarette smoking and breast cancer (chi(2)=6.455, P=0.018), the percentage of ever or current smokers was significantly higher in cases (7.1 %) than that in controls (1.2%). The distributions of allelotype and genotype of codon72, intron 3, and intron 6 were also not significantly different between cases and controls (P>0.05). No significant association was found between the risk of breast cancer and p53 polymorphisms. The genetic linkage disequilibrium existed in these three polymorphic sites in controls, and the Arg-A-G and Pro-A-G were the most common haplotypes both in cases and controls. There was no significant association of p53 haplotype with risk of breast cancer. CONCLUSION: p53 codon72, intron 3, and intron 6 polymorphisms may not be associated with the susceptibility of breast cancer. The Arg-A-G and Pro-A-G haplotypes are the most common haplotypes in Chinese Han population.

Air pollution and hospital visits for acute upper and lower respiratory infections among children in Ningbo, China: A time-series analysis.

Acute upper and lower respiratory infections are main causes of mortality and morbidity in children. Air pollution has been recognized as an important contributor to development and exacerbation of respiratory infections. However, few studies are available in China. In this study, we investigated the short-term effect of air pollution on hospital visits for acute upper and lower respiratory infections among children under 15 years in Ningbo, China. Poisson generalized models were used to estimate the associations between air pollution and hospital visits for acute upper and lower respiratory infections adjusted for temporal, seasonal, and meteorological effects. We found that four pollutants (PM2.5, PM10, NO2, and SO2) were significantly associated with hospital visits for acute upper and lower respiratory infections. The effect estimates for acute upper respiratory infections tended to be higher (PM2.5 ER = 3.46, 95% CI 2.18, 4.76; PM10 ER = 2.81, 95% CI 1.93, 3.69; NO2 ER = 11.27, 95% CI 8.70, 13.89; SO2 ER = 15.17, 95% CI 11.29, 19.19). Significant associations for gaseous pollutants (NO2 and SO2) were observed after adjustment for particular matter. Stronger associations were observed among older children and in the cold period. Our study suggested that short-term exposure to outdoor air pollution was associated with hospital visits for acute upper and lower respiratory infections in Ningbo.

[Association between genetic polymorphisms in folate metabolic enzyme genes and colorectal cancer: a nested case-control study].

OBJECTIVE: To investigate the interrelationship of genetic polymorphisms in folate metabolic enzymes (MTHFRC677T, MTHFRA1298C, MTRA2756G and MTRRA66G) and their combinative effects with colorectal cancer (CRC). METHODS: A nested case-control study was designed and carried out. 140 CRC patients and 343 control subjects were included in this study. Polymorphisms of folate metabolic enzyme genes were genotyped by PCR-restriction fragment length polymorphism method. Risk of CRC was estimated by unconditional logistic model, and P value for interaction was calculated by likelihood test. RESULTS: The allele of MTR2756G showed a positive association with CRC (OR = 2.04, 95% CI = 1.22 - 3.40). Those with MTHFR1298AA and MTR 2756AG/GG genotypes had an elevated risk with CRC (OR = 2.57, 95% CI, 1.42 -4.65), and their combinative effect showed a significant association with CRC (P = 0.04). CONCLUSION: MTR2756G allele may be a risk factor of CRC, and interaction may exsit between polymorphisms of MTHFRA1298C and MTRA2756G. Further studies with larger sample and in different ethnic groups are needed.