Menopause modified the association of blood pressure with osteoporosis among gender: a large-scale cross-sectional study.

Purpose: This study aimed to assess the potential association between blood pressure and osteoporosis in a rural population with limited resources. Existing evidence on this association is limited, particularly in such settings. Methods: Data from 7,689 participants in the Henan Rural Cohort study were analyzed. Four blood pressure indicators [systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP)] were measured. The logistic regression model and restricted cubic spline plots were used to assess the relationship between blood pressure indicators and osteoporosis prevalence. Results: Positive trends were noted between blood pressure indicators and osteoporosis prevalence in the entire group and women (P trend < 0.05 for SBP, MAP, and PP). Women with higher SBP and PP exhibited elevated odds of osteoporosis compared with those with the lowest SBP and PP (ORs ranging from 1.15 to 1.5 for SBP and 1.06 to 1.83 for PP). No such associations were found in men. These relationships were only evident in postmenopausal women. Dose-response analysis confirmed these findings. Excluding participants taking hypertension medication did not alter the results. Conclusion: In resource-limited settings, higher SBP and PP are associated with the increased prevalence of osteoporosis in women, potentially influenced by menopause-related factors. This indicates that potential gender-based differences and social inequalities may affect bone health. Clinical trial registration: The Henan Rural Cohort Study has been registered at the Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699) http://www.chictr.org.cn/showproj.aspx?proj=11375.

Association of nocturnal sleep duration and sleep midpoint with osteoporosis risk in rural adults: a large-scale cross-sectional study.

BACKGROUND: Evidence has suggested the linkage between sleep habits and several metabolic diseases, but the association of sleep factors with bone health remains unclear, especially in regions with low economic levels. Thus, this study aimed to investigate the relationship of nocturnal sleep duration and sleep midpoint with the osteoporosis risk in a rural population. METHOD: Eligible subjects were derived from the Henan Rural Cohort Study. The Pittsburgh Sleep Quality Index was applied to collect sleep information including sleep initiating time and wake-up time. The bone mineral density of the calcaneus was measured by the ultrasonic bone density apparatus. Multivariable logistic regression models and restricted cubic splines were utilized to evaluate the odds ratio (OR) and 95% confidence intervals (95% CI). RESULTS: For 8033 participants, 1636 subjects suffered from osteoporosis. Compared with the reference group (7 ~ h group), the ORs and 95% CI of osteoporosis associated with duration of nocturnal sleep were 1.32 (1.10, 1.56), 1.59 (1.25, 2.01), and 1.82 (1.25, 2.65) in the 8 ~ h, 9 ~ h, and ≥ 10 h group, respectively. Additionally, the adjusted ORs and 95% CI were 1.20 (1.01, 1.44) in the early sleep midpoint group and 1.09 (0.92, 1.29) in the intermediate sleep midpoint, compared with the late. Furthermore, there was a joint effect of long duration of nocturnal sleep and the early sleep midpoint on osteoporosis. CONCLUSION: Long duration of nocturnal sleep and early sleep midpoint were independently and jointly associated with higher risk of osteoporosis in rural areas. TRIAL REGISTRATION: The Henan Rural Cohort Study has been registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 06 July 2015. http://www.chictr.org.cn/showproj.aspx?proj=11375.

Effect modification of socioeconomic status on the association of exposure to famine in early life with osteoporosis in women.

BACKGROUND: The present study aimed to explore the effect of modification of socioeconomic status (SES) on the association between famine exposure in early life and osteoporosis in adulthood via the baseline data from the Henan Rural cohort study. METHODS: A total of 2669 exposed to famine participants were selected from the Henan Rural cohort, and the questionnaires, physical examination and bone mineral density measurement were completed. Specific birth years were used to define five groups: the fetal exposed group, early-childhood exposed group, mid-childhood exposed group, late-childhood exposed group and unexposed group. And the age-matched control group was a combination of the unexposed group and late-childhood exposed group. Multivariable logistic regression models were utilised to analyse the association of famine exposure in early life with osteoporosis in adulthood. RESULTS: The prevalence rates of osteoporosis of participants exposed to famine during the fetal period, early-childhood, mid-childhood and the age-matched group were 21.67%, 25.76%, 23.90% and 18.14%, respectively. The adjusted odds ratios (95% confidence interval) of participants suffering from famine during the fetal period, early-childhood and mid-childhood versus age-matched group were 1.19 (0.82-1.73), 1.40 (1.04-1.88) and 1.57 (1.16-2.13), respectively. The female participants yielded consistent results. The risk of osteoporosis was higher in more severe famine eara. Moreover, an attenuated effect of early life famine exposure on osteoporosis was observed in female participants with high SES. CONCLUSIONS: Exposure to famine in early life showed a sex-specific association with an increased risk of osteoporosis in adulthood and the severity of famine may exacerbate this association. In addition, the risk could be modified by SES.

A cell penetrating peptide-modified magnetic/fluorescent probe for in vivo tracking of mesenchymal stem cells.

Difficulty in precise tracking of the in vivo distribution and migration of transplanted stem cells in a noninvasive way is a great hurdle in regenerative medicine research. Paramagnetic element-doped upconversion nanoparticles (UCNPs) emerge as a kind of promising dual-modal imaging agents owing to the possibility in combining strong contrast of MR imaging and high efficiency of fluorescence imaging. Herein a kind of Mn-doped NaYF4-based UCNPs (NaYF4: 20%Yb, 2%Er, 30%Mn) was developed and then hydrophilized by various coatings, including cell penetrating peptide, DNA, and SiO2 . The UCNPs were denoted as Pep/UCNPs, DNA/UCNPs, and SiO2 /UCNPs, respectively. Their potential in cell labeling and in vivo tracking applications was comprehensively explored. The results show that the Mn-doped UCNPs possess high biocompatibility, high cell labeling efficiency, high MR resolution, and importantly a single emission at 660 nm, within optical window for in vivo imaging of biological targets. Particularly, mesenchymal stem cells (MSCs) pre-labeled by cell penetrating peptide-modified UCNPs (Pep/UCNPs) can be precisely monitored in terms of their distribution in mice over a long period of time by simultaneous MR and fluorescent imaging, which provided a noninvasive and double-checking tool for investigating the destination of stem cells in tissue regeneration.

Long-term exposure to air pollution might increase prevalence of osteoporosis in Chinese rural population.

OBJECTIVES: The associations of long-term exposure to air pollution with osteoporosis are rarely reported, especially in rural China. This study aimed to explore the association among rural Chinese population. METHODS: A total of 8033 participants (18-79 years) derived from the Henan Rural Cohort Study (n = 39,259) were included in this cross-sectional study. Exposure to air pollutants was estimated using machine learning algorithms with satellite remote sensing, land use information, and meteorological data [including particulate matter with aerodynamic diameters ≤1.0 µm (PM1), ≤2.5 µm (PM2.5), and ≤10 µm (PM10), and nitrogen dioxide (NO2)]. The bone mineral density of each individual was measured by using ultrasonic bone density apparatus and osteoporosis was defined based on the T-score ≤ -2.5. Multiple logistic regression models were used to examine the association of air pollution and osteoporosis prevalence. RESULTS: We observed that per 1 µg/m3 increase in PM1, PM2.5, PM10 and NO2 were associated with a 14.9%, 14.6%, 7.3%, and 16.5% elevated risk of osteoporosis. Compared with individuals in the first quartile, individuals in the fourth quartile had higher odds ratio (OR) of osteoporosis (P-trend < 0.001), the ORs (95% confidence interval) were 2.08 (1.72, 2.50) for PM1, 2.28 (1.90, 2.74) for PM2.5, 1.93 (1.60, 2.32) for PM10, and 2.02 (1.68, 2.41) for NO2. It was estimated that 20.29%-24.36% of osteoporosis cases could be attributable to air pollution in the rural population from China. CONCLUSIONS: Long-term exposure to air pollutants were positively associated with high-risk of osteoporosis, indicated that improving air quality may be beneficial to improve rural residents health.

Adiposity reduces the risk of osteoporosis in Chinese rural population: the Henan rural cohort study.

BACKGROUND: Adiposity plays a crucial role in the risk of osteoporosis. However, the impact of body fat distribution on the skeleton is contentious. The study was designed to explore the association of various adiposity indices with estimated bone mineral density (BMD) and the risk of osteoporosis based on body mass index (BMI), body fat percentage (BFP), waist circumference (WC), waist to hip ratio (WHR), waist to height ratio (WHtR), and visceral fat index (VFI). METHODS: A total of 8475 subjects derived from the Henan Rural Cohort Study were analyzed. The estimated BMD of study participants were measured by calcaneal quantitative ultrasound (QUS). Linear regression and binary logistic regression were performed to estimate the association of adiposity and the outcomes. RESULTS: The mean age of the study participants was 55.23 ± 11.09 years and 59.61% were women. The crude and age-standardized prevalence of high osteoporosis risk was 16.24 and 11.82%. Per unit increment in adiposity indices was associated with 0.005-0.021 g/cm2 increase in estimated BMD. The adjusted odds ratios (95% confidence interval) for high osteoporosis risk in per 1 SD increase of WC, WHR, WHtR, BMI, BFP, and VFI were 0.820 (0.748, 0.898), 0.872 (0.811, 0.938), 0.825 (0.765, 0.891), 0.798 (0.726, 0.878), 0.882 (0.800, 0.972), and 0.807 (0.732, 0.889), respectively. Stratified analyses indicated greater effects on individuals aged 55 years or older. CONCLUSIONS: The adiposity indices have an inverse association with the risk of osteoporosis among Chinese rural population, especially in the elderly.

Gender-specific prevalence and influencing factors of osteopenia and osteoporosis in Chinese rural population: the Henan Rural Cohort Study.

OBJECTIVE: The aims of this study were to describe distributions of the prevalence of osteopenia and osteoporosis and identify the potential risk factors by gender in a Chinese rural population. DESIGN: A cross-sectional survey. SETTING AND PARTICIPANTS: A total of 8475 participants (18-79 years) were obtained from the Henan Rural Cohort Study. Bone mineral density (BMD) of the calcaneus for each individual was measured by ultrasonic bone density apparatus. Logistic regression models were used to evaluate associations of potential risk factors with prevalence of osteopenia and osteoporosis. Furthermore, a meta-analysis of prevalence of osteoporosis which included eight studies was conducted to confirm this study results. RESULTS: The mean of BMD were 0.42 and 0.32 g/cm2 for men with osteopenia and osteoporosis (p<0.001), as well as 0.40 and 0.30 g/cm2 (p<0.001) for women with osteopenia and osteoporosis, respectively. The overall age-standardised prevalence of osteopenia and osteoporosis were 42.09% and 11.76% in all participants. The age-standardised prevalence of osteopenia in men (45.98%) was significantly higher than that in women (39.73%), whereas the age-standardised prevalence of osteoporosis in men (7.82%) was lower than that in women (14.38%). Meta-analysis results displayed pooled prevalence of osteoporosis of 18.0% (10.1%-25.8%) in total sample, 7.7% (5.7%-9.7%) in men and 22.4% (17.1%-27.6%) in women. Multivariable logistic regression models showed that ageing, women, low education level or income, drinking or underweight was related to increased risk for osteopenia or osteoporosis. CONCLUSIONS: About one-sixth of the participants suffered osteoporosis in rural China, and the prevalence in women was higher than men. Although the results were lower than that of meta-analysis, osteoporosis still accounts for huge burden of disease in rural population due to limited medical service and lack of health risk awareness rather than urban area. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR-OOC-15006699; Pre-results).

Epidemiology and prevalence of hyperuricemia among men and women in Chinese rural population: The Henan Rural Cohort Study.

Objective: The aim of this study was to explore the latest prevalence of hyperuricemia and influencing factors in Chinese rural population.Methods: A survey was conducted from July 2015 to September 2017. A total of 38,855 (15,371 men and 23,484 women) subjects were recruited from the Henan Rural Cohort Study. Hyperuricemia was defined as a serum urate level of >7.0 mg/dL for men and >6.0 mg/dL for women. A meta-analysis of 19 studies that focused on hyperuricemia prevalence was performed to validate the result of the cross-sectional survey.Results: The crude and age-standardized prevalence of hyperuricemia was 10.24% and 12.60%, respectively. The prevalence of hyperuricemia decreased in men with increasing age, but the opposite trend was observed in women. The results of meta-analysis demonstrated that hyperuricemia prevalence in Chinese rural areas was 11.7%, consistent with the result of current survey. Multivariate logistic regression revealed that overweight or obesity, hypercholesterolemia, hypertriglyceridemia, hypoalphalipoproteinemia and high serum creatinine level could increase the risk of hyperuricemia, while high physical activity and fasting plasma glucose were associated with a lower risk of hyperuricemia in all participants.Conclusion: The latest prevalence of hyperuricemia is high in rural China and is associated with multiple factors, indicating that prevention and control strategies for hyperuricemia are needed urgently.

Contribution of serum lipids as effect modifiers to a relationship between mean arterial pressure and coronary heart disease in Chinese rural population: the Henan Rural Cohort Study.

OBJECTIVES: The aim of this study was to evaluate the relationship between mean arterial pressure (MAP) and coronary heart disease (CHD) in Chinese rural population. In addition, we hypothesised that this relationship might be mediated by some degree of serum lipids. DESIGN: This is a cross-sectional study. SETTING: The participants were from the Henan Rural Cohort Study, initiated in five rural areas (Tongxu county of Kaifeng city, Yima county of Sanmenxia city, Suiping county of Zhumadian city, Xinxiang county of Xinxiang city and Yuzhou county of Xuchang city) in Henan Province, China, during July 2015 and September 2017. PARTICIPANTS: The study included 39 020 subjects aged 18-79 years as current research population. OUTCOME MEASURES: Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using an electronic sphygmomanometer. MAP was calculated by one-third SBP plus two-thirds DBP. The study used restricted cubic splines and logistic regression models to evaluate the ORs and 95% CIs. Mediation analysis using bootstrap was performed to examine the contribution of serum lipids to MAP-related CHD. RESULTS: The adjusted OR (95% CI) for the highest MAP quartile with the risk of CHD was 1.45 (1.24 to 1.69) compared with the lowest quartile. Simultaneously, each 1-SD increment in MAP was significantly associated with a 12% increased risk of CHD. A linear dose-response relationship between MAP and CHD was found (p value for non-linear=0.1169) in the fully adjusted model. We further reported that 36.07% of proportion explained risk of CHD was mediated through serum lipids. CONCLUSIONS: Increased MAP was a significant marker of CHD in Chinese rural population. Meanwhile, the relationship was mediated by some degree of serum lipids, and triglyceride was the strongest mediator. TRIAL REGISTRATION NUMBER: Henan Rural Cohort study has been registered at Chinese Clinical Trial Register (ChiCTR-OOC-15006699) and the stage it relates to is Post-results.

Optimization of the Gal4/UAS transgenic tools in zebrafish.

The Gal4/UAS system provides a powerful tool to analyze the function of genes. The system has been employed extensively in zebrafish; however, cytotoxicity of Gal4 and methylation of UAS can hinder future applications of Gal4/UAS in zebrafish. In this study, we provide quantitative data on the cytotoxicity of Gal4-FF and KalTA4 in zebrafish embryos. A better balance between induction efficiency and toxicity was shown when the injection dosage was 20 pg for Gal4-FF and 30 pg for KalTA4. We tested the DNA methylation of UAS in different copies (3×, 5×, 7×, 9×, 11×, and 14×), and the results showed, for the first time, that the degree of UAS methylation increases with the increase in the copy number of UAS. We detected insertions of the Tol2-mediated transgene in the Gal4 line and found as many as three sites of insertion, on average; only about 20% of individuals contained single-site insertion in F1 generation. We suggested that the screening of Gal4 lines with single-site insertion is essential when Tol2-mediated Gal4 transgenic lines are created. Moreover, we designed a novel 5 × non-repetitive UAS (5 × nrUAS) to reduce the appeal of multicopy UAS as a target for methylation. Excitingly, the 5 × nrUAS is less prone to methylation compared to 5 × UAS. We hope the results will facilitate the future application of the Gal4/UAS system in zebrafish research.

Independent and combined effects of resting heart rate and pulse pressure with metabolic syndrome in Chinese rural population: The Henan Rural Cohort study.

BACKGROUND: We examined the independent and cumulative associations of resting heart rate and pulse pressure with metabolic syndrome in Chinese rural population based on epidemiological research. METHODS: A total of 38,708 participants were derived from the Henan Rural Cohort study. Restricted cubic splines and logistic regression model were used to estimate the odds ratios and 95% confidence intervals of metabolic syndrome risk in relation to resting heart rate and pulse pressure. RESULTS: After adjusting for potential confounders, the odds ratio (95% confidence intervals) of resting heart rate and pulse pressure in the highest quartile with the risk of metabolic syndrome were 1.59 (1.48-1.70) and1.81 (1.67-1.95), respectively. Simultaneously, the cumulative effect analysis indicated that the adjusted the odd ratio of resting heart rate and pulse pressure in the highest quartile was 2.89 (2.40-3.47). Furthermore, there was a significantly additive interaction between resting heart rate and pulse pressure on the risk of metabolic syndrome. CONCLUSION: Increased resting heart rate and pulse pressure are associated with the higher risk of metabolic syndrome as well as the influences of resting heart rate with pulse pressure might cumulatively increase the risk of metabolic syndrome. However, the potential clinical application remains to be determined.

Sex-specific associations of serum uric acid with metabolic syndrome in Chinese rural population: The RuralDiab study.

BACKGROUND: We explored the association between serum uric acid (SUA) and metabolic syndrome (MetS) in Chinese rural adults. METHODS: A total of 16,577 subjects (6354 men and 10,223 women) were from the RuralDiab study. SUA concentration was measured by the enzymatic colorimetric method. A meta-analysis including 12 eligible studies focused on SUA and MetS was preformed to confirm the findings of the cross-sectional study. RESULTS: After adjustment for age, educational level, and other covariates, the odds ratio (ORs) for MetS increased smoothly with the increasing SUA concentration in both sexes (P for no-linear trend > 0.05). The adjusted ORs of MetS comparing the fourth and firstly quartiles were 3.11 [95% CI: 2.58-3.74] in men and 3.64 [95% CI: 3.22-4.11] in women (Ptrend < 0.001). In continuous analysis, each 1 mg/dl increment in SUA concentration was significantly associated with a 41% increased risk of MetS in men and 62% in women. The meta-analysis validated the positive association between SUA and MetS (pooled OR: Men, 1.80 [95% CI: 1.57-2.07]; Women, 2.46 [95% CI: 1.95-3.12]). CONCLUSION: SUA concentration was positively with the prevalence of MetS in Chinese rural population, and more studies are needed to explore the mechanisms of the relationship. WHAT IS ALREADY KNOWN ON THIS TOPIC?: Previous studies have explored the association between serum uric acid and metabolic syndrome, but evidence on the strength and consistency of the association remains uncertain and limited, especially in rural population. In addition, the epidemiological research and meta-analysis on the association have not been reported. WHAT DOES THIS STUDY ADD?: The results of this study showed that serum uric acid was significantly associated with metabolic syndrome and its components in Chinese rural population. Furthermore, the findings demonstrated that the significant associations varied across sex. In addition, the results of epidemiological research were similar with the meta-analysis, which demonstrates the credible of the results of the epidemiology research.

Independent and cumulative effects of resting heart rate and pulse pressure with type 2 diabetes mellitus in Chinese rural population.

The purpose was to explore the effects of resting heart rate (RHR) and pulse pressure (PP) independently as well as their cumulative effects on the risk of type 2 diabetes mellitus (T2DM) through cross-sectional study plus meta-analysis. A total of 8276 subjects aged 35-74 years from the Rural Diabetes, Obesity and Lifestyle (RuralDiab) study were included in the study. Meanwhile, two meta-analyses were conducted to validate the results of the epidemiological research. The results showed that RHR and PP were associated with higher risk of T2DM, and the corresponding adjusted OR(95%CI) for each quartiles were 1.00, 0.99(0.68-1.42), 1.58(1.13-2.20), 2.93(2.15-3.98) and 1.00, 1.06(0.75-1.48), 1.11(0.79-1.56), 1.45(1.03-2.03), respectively. The cumulative effect analysis indicated that the adjusted OR(95%CI) in the fast RHR-high PP were 3.36(2.26-4.99), 2.60(1.47-4.59), and 3.60(2.09-6.20) compared with the slow RHR-low PP for total population, male and female, respectively. Meta-analysis showed that the pooled effect values for RHR and PP were 1.94(1.64-2.31) and 1.25(1.04-1.51), respectively. This study demonstrated that elevated RHR and PP are independently associated with the risk of T2DM as well as the influences of conventional confounders, and fast RHR with high PP might cumulatively increase the risk of T2DM. However, the potential clinical application remains to be determined.

Expression of nucleostemin, epidermal growth factor and epidermal growth factor receptor in human esophageal squamous cell carcinoma tissues.

OBJECTIVE: To determine the expression of nucleostemin (NS), epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) mRNA in human esophageal squamous cell carcinoma (ESCC) tissues and their association in a human ESCC cell line. METHODS: The expression of NS, EGF and EGFR mRNA was determined in paired normal esophageal and ESCC tissues of 62 patients using in situ hybridization. The association between NS and EGF or EGFR was examined using immunoblotting and real time polymerase chain reaction in a human ESCC cell line transfected with NS siRNA or treated with a selective EGFR inhibitor. RESULTS: In normal esophageal and ESCC tissues, the positive detection rates were 21.0% (13/62) and 69.4% (43/62) for NS mRNA staining, 40.3% (25/62) and 77.4% (48/62) for EGF mRNA staining, and 30.6% (19/62) and 75.8% (41/62) for EGFR mRNA staining, respectively. These results indicated that NS, EGF and EGFR mRNA expression was upregulated mostly in ESCC tissues. Moreover, the expression of NS, EGF and EGFR mRNA was positively correlated with tumor grade, invasion and lymphatic metastasis of ESCC cells. NS mRNA was co-expressed with EGF and EGFR mRNA in ESCC tissues. The in vitro studies using a human ESCC cell line showed that knockdown of NS with NS siRNA significantly reduced EGF and EGFR expression. However, inhibition of the EGFR kinase activity with a specific EGFR kinase inhibitor had minimal effect on NS expression. CONCLUSION: The upregulation of NS, EGF and EGFR mRNA frequently occurs in ESCC tissues and is associated with malignancy of human esophageal squamous tumors. NS is required for EGF and EGFR expression.

[Expression of nucleostemin mRNA and protein in the esophageal squamous cell carcinoma].

OBJECTIVE: To investigate the mRNA and protein expression of nucleostemin (NS) in human esophageal squamous cell carcinoma. METHODS: The mRNA and protein expression of NS were detected in 31 mucosal atypical hyperplasia specimens, 62 esophageal squamous cell carcinoma specimens and the matched normal esophageal mucosa samples by RT-PCR and immunohistochemistry method, respectively. RESULTS: The positive expression rate of NS protein in normal esophageal mucosa, atypical hyperplasia and esophageal squamous cell carcinoma was 17.7% (11/62), 41.9% (13/31) and 69.4% (43/62), respectively. There was a significant difference among the above three groups (chi2 = 33.676, P < 0.01). The expression levels of NS mRNA in esophageal squamous cell carcinoma (0.971 +/- 0.121) was significantly higher than that in the atypical hyperplasia (0.913 +/- 0.085) and also in the normal esophageal mucosa (0.866 +/- 0.103; F = 14.829, P < 0.01). The expression level of both NS protein and mRNA was positively correlated with histological grade, infiltration depth, and lymph node metastasis (P < 0.05), but not with age, gender or pathological type (P > 0.05). CONCLUSION: Our results indicate that nucleostemin mRNA and protein are over-expressed in human esophageal squamous cell carcinoma, and it may be related with its oncogenesis.

[mRNA expression level of nucleostemin in esophageal squamous cell carcinoma tissue].

OBJECTIVE: To investigate the mRNA expression levels of nucleostemin (NS) in human esophageal squamous cell carcinoma tissue. METHODS: Real-time PCR was used to quantify the mRNA expression of NS in the samples of esophageal squamous cell carcinoma tissue and their matched normal esophageal mucosa tissue from 62 patients, 36 males and 26 females, aged (61 +/- 10) (38-75). The relationship between NS mRNA expression level and clinical pathological features was analyzed. RESULTS: The NS mRNA expression level of the 62 cases of esophageal squamous cell carcinoma tissue was(4.5 +/- 2.1), significantly higher than that of the matched normal esophageal mucosa tissue [(2.1 +/- 1.3), t = -5.045, P = 0.000]. The mRNA expression level of NS was associated with tumor grade, depth of infiltration, and lymph node metastasis (all P < 0.05), but not with gender, age, and pathological type (all P > 0.05). Multiple linear regression analysis revealed that clinical and pathological features influenced the NS mRNA expression level (P = 0. 000), and the depth of infiltration and lymph node metastasis were important influencing factors for NS mRNA expression level(both P < 0.05). CONCLUSION: NS may play an important role in the progression and proliferation of esophageal squamous cell carcinoma.

[Construction and identification of a eukaryotic expression vector for the small interfering RNA targeting nucleostemin gene].

OBJECTIVE: To construct a eukaryotic expression vector for the small interfering RNA (siRNA) targeting nucleostemin (NS) gene. METHODS: The siRNA targeting NS gene was designed according to the sequence of NS mRNA available in GenBank. Three siRNA sequences were obtained, and the corresponding cDNAs were synthesized and inserted into plasmid pRNAT-U6.1 for constructing the recombinant plasmids, which were transformed into E.coli DH5alpha strain. The plasmids, after identification by PCR and DNA sequencing, were transfected into EC9706 cell line via liposome, and the mRNA and protein expressions of NS gene in the cells were determined by RT-PCR and Western blotting, respectively. RESULTS: Three recombinant plasmids were identified by PCR and sequence analysis, the results of which showed correct insertion of the designed sequences in the plasmids. RT-PCR and Western blotting showed substantially decreased mRNA and protein expressions of NS gene in the transfected cells. CONCLUSION: The recombinant plasmid expressing the siRNA targeting NS gene has been successfully constructed, which provides the basis for studying RNA interference of the NS gene.

[Detection of methylation of hMSH2 gene promoter region of esophageal cancer].

OBJECTIVE: To detect methylation in promoter region of hMSH2 gene in esophageal cancer. METHODS: Specimens of cancer and normal tissues freshly removed from 32 cases of esophageal cancer patients without previous radiotherapy, chemotherapy or other treatment were preserved at -80 degrees C within 30 min. Methylation specific PCR (MSP) was used to detect methylation of mismatch repair gene (MMR) hMSH2 in promoter region in esophageal cancer and normal esophageal tissues. RESULTS: The frequencies of methylation of hMSH2 gene in promoter region of cancer and normal esophageal tissues were 32.4% (11/32) and 0/30 (0%), respectively, and significant difference was found between the two groups (P < 0.01). The frequency of methylation in elder patients (> or = 70 years old) was significantly higher than that in younger patients (< 70 years old) (P < 0.05). Methylation was less frequently found in grade I-II (18.2%) than in grade III-IV (70.0%) (P < 0.05). CONCLUSION: Methylation of hMSH2 gene in promoter region is related to patients' age and histopathological grade of the esophageal cancer.

[Expression of hMSH2 gene in esophageal cancer].

OBJECTIVE: To observe the expression of DNA mismatch repair gene hMSH2 mRNA in esophageal cancer tissues. METHODS: This study included 32 esophageal cancer patients who received no previous radiotherapy, chemotherapy or other treatments. Within 30 min following surgical removal of the tumor tissues, specimens of the tumor, the tissue adjacent to the tumor and normal tissue at the esophageal stump (1 cmx1 cmx1 cm in size for each specimen) were obtained for examining hMSH2 expression with hMSH2 ISH detection kit. RESULTS: The positivity rate of hMSH2 was 46.88% in the esophageal cancer tissues, 53.12% in the adjacent tissues, and 84.38% in normal tissues at the esophageal stump, showing significant difference of the former two tissues from the normal tissue (P<0.05). No significant correlation was noted between the positivity rate of hMSH2 and such factors as the patients' age, sex, tumor size, tumor location, pathological type, histological grade, lymphatic metastasis or degree of tumor invasion (P>0.05). CONCLUSION: The deletion of hMSH2 is an early event in the development of esophageal cancer.