Characteristics of flight delays during solar flares

Solar flares are one of the severest solar activities that have important effects on near-Earth space. Previous studies have shown that flight arrival delays increase as a result of solar flares, but the intrinsic mechanism behind this relationship is still unknown. In this study, we conducted a comprehensive analysis of flight departure delays during 57 solar X-ray events by using a huge amount of flight data (~ 5 × 10⁶ records) gathered over a 5-year period. It is found that the average flight departure delay time during solar X-ray events increased by 20.68% (7.67 min) compared to quiet periods. Our analysis also revealed apparent time and latitude dependencies, with flight delays being more serious on the dayside than on the nightside and longer (shorter) delays tending to occur in lower (higher) latitude airports during solar X-ray events. Furthermore, our results suggest that the intensity of solar flares (soft X-ray flux) and the Solar Zenith Angle directly modulate flight departure delay time and delay rate. These results indicate that communication interferences caused by solar flares directly affect flight departure delays. This work expands our conventional understanding of the impacts of solar flares on human society and provides new insights for preventing or coping with flight delays.

Can the parental socio-economic status promote the children to participate in physical exercise? An empirical study based on the survey data of CGSS 2017

OBJECTIVE

This paper discusses the promotion effect and mechanism of the parental socio-economic status (SES) on their offspring's participation in physical exercise and provides direction and guidance for the formulation of sports public policies.

MATERIALS AND METHODS

7,965 data were obtained from the 2017 Chinese General Social Survey (CGSS) dataset. To investigate the effect and mechanism of parental SES in encouraging offspring to engage in physical activity, this paper used a binary logistic regression model and an ordinal logistic regression model. The moderating effects of urban-rural variables and birth cohorts were explored through hierarchical regression analysis and regression coefficient difference test. Robustness tests were performed by sample screening and model replacement.

RESULTS

After controlling for related variables, the parental SES can improve the possibility of children's participation in physical exercise (OR = 1.134, p < 0.01). Part of this promotion effect is realized by improving their children's education level (19.87%) and social communication (2.56%), and the promotion effect increases gradually with the passage of time and social changes. The robustness test results show that the empirical research results are reliable.

CONCLUSIONS

The parental SES can promote their children to participate in physical exercise.

[Progress in cohort study of lung cancer in high-risk population in communities]

The cohort study of lung cancer in high-risk population in communities in China was a part of Lung Cancer Cohort Study initiated in 2017 and funded by Precision Medicine Research of National Key Research and Development Program. Around 50 000 participants from the communities were enrolled from 7 cities in 7 regions in China. Information about the risk factors for lung cancer were collected and the populations at high risk for lung cancer were identified. Then, low-dose CT (LDCT) screening of lung cancer was conducted in the populations at high risk, and further information about the diagnosis of lung cancer cases and death cases were collected. Therefore, a community population-based cohort was established for lung cancer risk factor exposure survey, high risk population evaluation, LDCT screening and lung cancer case and death follow up. Meanwhile, biological samples were collected from all the participants in the cohort to support the future precision medicine research of lung cancer.

[Total cholesterol and the risk of primary liver cancer in Chinese males: a prospective cohort study]

Objective: To investigate the association between total cholesterol (TC) and primary liver cancer in Chinese males. Methods: Since May 2006, all the male workers, including the employees and the retirees in Kailuan Group were recruited in the Kailuan male dynamic cohort study. Information about demographics, medical history and TC levels was collected at the baseline interview, as well as information on newly-diagnosed primary liver cancer cases during the follow-up period. A total of 110 612 males were recruited in the cohort by 31 December 2015. TC levels were divided into four categories by quartile (<4.27, 4.27-4.90, 4.90-5.56 and ≥5.56 mmol/L), with the first quartile group serving as the referent category. Cox proportional hazards regression model was used to evaluate the association between TC levels and primary liver cancer risk. Results: By December 31, 2015, a follow-up of 861 711.45 person-years was made with a median follow-up period of 8.83 years. During the follow-up, 355 primary liver cancer cases were identified. Compared with the first quartile, the HR of incident primary liver cancer among participants with the second, third and highest quartile TC levels were 0.76 (95%CI: 0.58-1.01), 0.59 (95%CI: 0.43-0.79), and 0.36 (95%CI: 0.25-0.52), respectively after adjusting for age, educational level, income level, smoking status, drinking status, body mass index, and HBsAg status (P_{for trend}<0.001). Subgroup analyses found that the association between TC levels and primary liver cancer was robust (all P_{for trend}<0.05). The results didn't change significantly after exclusion of newly-diagnosed cases within the first 2 years, males with history of cirrhosis or subjects who took antihyperlipidemic drugs, participants with higher TC levels had a lower risk of primary liver cancer (all P_{for trend}<0.05) and HR(95%CI) of incident primary liver cancer among participants with the highest quartile TC levels were 0.41 (0.28-0.61), 0.36 (0.25-0.53) and 0.38 (0.26-0.54), respectively. Conslusion: In this large prospective study, we found that baseline TC levels were inversely associated with primary liver cancer risk, and low TC level might increase the risk of primary liver cancer.

[The development and validation of risk prediction model for lung cancer: a systematic review]

Objective: To systematically understand the global research progress in the construction and validation of lung cancer risk prediction models. Methods: "lung neoplasms" , "lung cancer" , "lung carcinoma" , "lung tumor" , "risk" , "malignancy" , "carcinogenesis" , "prediction" , "assessment" , "model" , "tool" , "score" , "paradigm" , and "algorithm" were used as search keywords. Original articles were systematically searched from Chinese databases (CNKI, and Wanfang) and English databases (PubMed, Embase, Cochrane, and Web of Science) published prior to December 2018. The language of studies was restricted to Chinese and English. The inclusion criteria were human oriented studies with complete information for model development, validation and evaluation. The exclusion criteria were informal publications such as conference abstracts, Chinese dissertation papers, and research materials such as reviews, letters, and news reports. A total of 33 papers involving 27 models were included. The population characteristics of all included studies, study design, predicting factors and the performance of models were analyzed and compared. Results: Among 27 models, the number of American-based, European-based and Asian-based model studies was 12, 6 and 9, respectively. In addition, there were 6 Chinese-based model studies. According to the factors fitted into the models, these studies could be divided into traditional epidemiological models (11 studies), clinical index models (6 studies), and genetic index models (10 studies). 15 models were not validated after construction or were cross-validated only in the internal population, and the extrapolation effect of models was not effectively evaluated; 8 models were validated in single external population; only 4 models were verified in multiple external populations (3-7); the area under the curve (AUC) of models ranged from 0.57 to 0.90. Conclusion: Research on risk prediction models for lung cancer is in development stage. In addition to the lack of external validation of existing models, the exploration of potential clinical indicators was also limited.

[Progress in epidemiologic research of association between anthropometric indicators and risk for gastric cancer]

Gastric cancer is one of the most common cancer. Studies have been conducted to evaluate the association between anthropometric indicators and gastric cancer, but the results were inconsistent. Therefore, a literature retrieval was conducted by using PubMed and Wanfang databases to summarize the latest research progress in the cohort study of the association between anthropometric indicators and the risk for gastric cancer. It was found that both general obesity and abdominal obesity might increase the risk for gastric cancer, while the association between underweight and gastric cancer needs further study. This paper summarizes the progress in the cohort study of association between anthropometric indicators for the risk for gastric cancer in order to provide evidence for the prevention and control of gastric cancer.

[Progress in construction and verification of colorectal cancer risk prediction models: a systematic review]

Objective: To systematically review available risk prediction models evidence on construction and verification of colorectal cancer risk prediction models. Methods: "Colorectal neoplasms", "risk assessment", "colorectal cancer", "colorectal tumor", "colon cancer", "colon tumor", "rectal cancer", "rectal tumor", "anal cancer", "anal tumor", "risk prediction", "malignancy", "carcinogenesis", "model" were used as search keywords. Journal papers and grey literature were searched from Chinese electronic databases (CNKI and Wanfang) and English electronic databases (PubMed and Embase) from their inception to 30 Apr 2018. The language of literature was restricted to Chinese and English. The inclusion criteria were human-oriented researches with complete information for model construction,verification and evaluation. The exclusion criteria were informal publications such as conference abstracts, Chinese disertation papers, and non-primary research materials such as reviews,letters,and news reports. Descriptive characteristics,targeted population, study design, model construction method and prediction results were extracted. A total of 36 papers involving 27 models were included. The population characteristics of all included studies,the type of research, the method of model construction and the prediction results of the model were analyzed. Results: As for model construction,there were 13 European and American population based model studies,14 Asian population based model studies,including 7 Chinese mainland based model studies. According to the factors selected into the model, these models can be divided into traditional epidemiological models (17 models), clinical index combined models (4 models),and genetic susceptibility index combined models (6 models). As for model verification,only 9 models were cross-verified in the internal population after model construction, and the extrapolation of model prediction effect was not effectively evaluated; 17 models were verified in an external population; there was only one model verified in two external populations in terms of risk prediction effect; the area under the curve of 27 models was 0.56-0.85. Conclusion: The risk prediction model of colorectal cancer is in the development stage. The external evaluation of model prediction effect is less and the prediction ability is not good, and the existing models have limited exploration of clinical indicators.

[The relationship between inflammatory markers and the risk of lung cancer: a prospective cohort study]

Objective: To investigate whether elevated levels of C-reactive protein (CRP) and neutrophil (NE) in the blood is associated with an increased risk of lung cancer incidence. Methods: From 2006 to 2007, all employees and retirees from Kailuan (Group) Limited liability Corporation were included in this Kailuan Cohort study. The last follow-up date was December 2015. Data on new cases of lung cancer were collected, and multivariable Cox proportional hazards regression models were used to the relationship between baseline CRP and NE at baseline and risk of lung cancer. Results: A total of 92 735 participants were enrolled in this study. During the follow-up, 850 new cases of lung cancer were identified. All subjects were divided into four groups according to the combination level of CRP and NE at baseline: CRP≤3 mg/L and NE≤4×10(9)/L(Group A), CRP≤3 mg/L and NE>4×10(9)/L(Group B), CRP>3 mg/L and NE≤4×10(9)/L(Group C), CRP>3 mg/L and NE>4×10(9)/L(Group D). The cumulative incidence of lung cancer were 950/100 000, 1 030/100 000, 1 081/100 000 and 1 596/100 000 in these four groups, respectively (P<0.001). Multivariate Cox proportional risk model showed that participants from Group D had an significantly increased 72% risks of lung cancer when compared to Group A (95% CI: 1.40~2.12, P<0.001). Stratified analyses gender showed that males in Group D had higher risk of lung cancer when compared with participants in Group A (HR=1.73, 95% CI: 1.40~2.15, P<0.001). Conclusion: Elevated levels of CRP and NE might increase the risk of lung cancer.

CX3CR1 participates in pulmonary angiogenesis in experimental hepatopulmonary syndrome mice through inhibiting AKT/ERK signaling pathway and regulating NO/NOS release

OBJECTIVE

Hepatopulmonary syndrome (HPS) is a kind of pulmonary microvascular disease and occurs in 15%-30% cirrhosis. This study aimed to investigate the effects of pulmonary CX3CR1 on angiogenesis and associated mechanisms in HPS animal models.

MATERIALS AND METHODS

CX3CR1GFP/GFP mice were constructed by replacing CX3CR1 with GFP. Common bile duct ligation (CBDL) mouse model was established with surgery. Release of nitric oxide (NO) was evaluated. Hematoxylin-eosin (HE) staining was employed to examine the inflammation of lung tissues. CD31 expression was detected with immunohistochemistry assay. Western blotting was used to evaluate the expression of CX3CL1, CX3CR1, phosphorylated-AKT (p-AKT), phosphorylated-ERK (p-ERK). Quantitative Real Time-PCR (qRT-PCR) assay was used to examine VEGF, PDGF, iNOS, eNOS, and HO-1 expression.

RESULTS

CX3CR1-deficiency (CX3CR1GFP/GFP-sham or CX3CR1GFP/GFP-CBDL mice) significantly reduced NO release compared to wide type (WT)-mice or WT-CBDL mice (p<0.05). CX3CR1-deficiency significantly alleviated inflammation compared to wide type (WT)-mice or WT-CBDL mice (p<0.05). CX3CR1-deficiency significantly reduced CD31 expression compared to WT-sham and WT-CBDL mice, respectively (p<0.05). CX3CR1 also participated in anti-angiogenesis efficacy of Bevacizumab. CX3CR1-deficiency significantly down-regulated the ratio of p-AKT/AKT and p-ERK/ERK and inhibited the secretion of VEGF and PDGF compared to WT-mice (p<0.05). CX3CR1-deficiency significantly reduced iNOS, eNOS, and HO-1 expression compared to WT-mice (p<0.05).

CONCLUSIONS

CX3CR1 deficiency reduced VEGF and PDGF production, inhibited p-AKT, and p-ERK activation and down-regulated iNOS, eNOS, and HO-1 expression. Therefore, CX3CR1 participates in pulmonary angiogenesis in the experimental HPS mice via inhibiting AKT/ERK signaling pathway and regulating NO/NOS release. These findings would provide a potential insight for clarifying the pathological mechanisms of HPS.

[Systematic review of the methodology quality and reporting quality in colorectal cancer screening guidelines]

Objective: To systematically review the quality and reporting quality of colorectal cancer screening guidelines, and to provide reference for the update of colorectal cancer screening guidelines and colorectal cancer screening in China. Methods: "Colorectal cancer", "colorectal tumor", "screening", "screening", "guide", "consensus", "Colorectal cancer", "Colorectal neoplasms", "Screening", "Early Detection of Cancer", "Guideline" and "recommendation" were used as search keywords. The literature retrieval for all the Chinese and English guidelines published before April 2018 was conducted by using PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, China Biology Medicine disc (CBMdisc), Cochrane Library, Guideline International Network, China Guidelines Clearinghouse (CGC) and the official website of the US Preventive Services Task Force (USPSTF), the American Cancer Society (ACS), International Agency for Research on Cancer (IARC), Australia Cancer Council (ACC) and Association of Coloproctology of Great Britain & Ireland (ACPGBI). The inclusion criteria were independent guidance documents for colorectal cancer screening. The language is limited to Chinese and English. The exclusion criteria were literature on interpretation, evaluation, introduction, etc., as well as the translated version of the guide and old guides. The quality and reporting norms of colorectal cancer screening guidelines were compared and evaluated using the European Guideline Research and Assessment Tool (AGREE Ⅱ) and the Practice Guideline Reporting Standard (RIGHT). Results: A total of 15 guides were included. The results of the AGREE Ⅱ quality evaluation showed that the overall quality of 15 guides was high. Among them, there were 9 guides with an overall score of 50 or more, 10 with a recommendation level of "A", and 2 with a rating of "B". There were 3 guides for "C"; each guide scores higher in scope and purpose, and clarity, and scores vary greatly in the areas of participants, rigor, applicability, and independence. The results of the RIGHT evaluation showed that 15 guides were insufficient in six areas except for background information, evidence, recommendations, reviews and quality assurance, funding and conflict of interest statements and management, and other aspects. Conclusion: The overall quality of included guidelines for colorectal cancer screening is high, but the normative nature needs to be strengthened.

[Association between total cholesterol and risk of lung cancer incidence in men: a prospective cohort study]

Objective: To assess the association and intensity of baseline TC level with the incidence of lung cancer in men in China. Methods: Since May 2006, all the male workers, including the employees and the retirees in Kailuan Group were recruited in the Kailuan male dynamic cohort study. Information about demographics, medical history, anthropometry and TC level were collected at the baseline interview, as well as the information of newly-diagnosed lung cancer cases during the follow-up period. According to guidelines for blood lipids in Chinese adults and the distribution in the population, TC level was classified into five groups as followed: <160, 160-, 180-, 200- and ≥240 mg/dl, with the second quintile group (160- mg/dl) serving as the referent category. Cox proportional hazards regression model and restricted cubic spline (RCS) model were used to evaluate the association and the nonlinear association between baseline TC level and the risk of lung cancer in the men. Results: By December 31, 2014, for the 109 884 men, a follow up of 763 819.25 person-years was made with a median follow-up period of 7.88 years. During the follow up, 808 lung cancer cases were identified. After adjustment for age, education level, income level, smoking status, alcohol consumption level, history of dust exposure, FPG level and BMI, HR (95%CI) of lung cancer for men with lower TC level (<160 mg/dl) and higher TC level (≥240 mg/dl) were 1.34 (1.04- 1.72) and 1.45 (1.09-1.92), respectively, compared with men with normal TC level (160- mg/dl). The results didn't change significantly after exclusion of newly diagnosed cancer cases within 2 years of follow up and subjects with the history of hyperlipidemia. Conclusion: Our results showed that TC might be associated with higher risk of lung cancer. Men with lower TC level or higher TC level had higher risk for lung cancer. Keep moderate TC level might be one of the effective precaution for the prevention of lung cancer.

[Alcohol consumption and the risk of lung cancer in males: a prospective cohort study]

Objective: To investigate the association between alcohol consumption and lung cancer risk in Chinese males. Methods: Information on alcohol consumption and outcomes were collected on a biennial basis among males in Kailuan Cohort (2006-2015). In addition, electronic databases of hospitals affiliated to Kailuan Community, Insurance Systems of Kailuan Community and Tangshan were also used for supplementary information retrieval. Cox proportional hazards regression models were used to evaluate the hazard ratio (HR) and 95%CI of baseline frequency and type of alcohol consumption associated with lung cancer risk in males. Non-drinkers were used as control group. Results: A total of 101 751 males were included and 913 new lung cancer cases were identified in the Kailuan male cohort study, with a total follow-up time of 808 146.56 person-years and a median follow-up time of 8.88 years by 31 December 2015. After adjusting for potential confounding factors, the HR of former drinkers, occasional drinkers (<1/day) and drinkers (≥1/day) were 1.30 (95%CI: 0.90-1.88), 0.80 (95%CI: 0.64-1.01) and 1.04 (95%CI: 0.85-1.27), respectively, compared with non-drinkers. In addition, drinking beer/red wine (HR=0.91, 95%CI: 0.69-1.20) and white wine (HR=0.99, 95%CI: 0.83-1.19) showed no significant association with lung cancer. The results were similar when stratified analysis were conducted. Conclusion: Our study results don't support the hypothesis that alcohol consumption is significantly associated with the risk of lung cancer in males.

[Relationship between inflammatory markers and the risk of colorectal cancer in Kailuan male cohort]

Objective: To investigate whether elevated levels of high sensitivity C-Reactive Protein (hsCRP) and neutrophil (NE) at baseline are associated with an increased risk of colorectal cancer in Kailuan male cohort. Methods: Since May 2006, males from Kailuan cohort were included in this study. Information on demographics, medical history, anthropometry, hsCRP and NE were collectedat baseline for all subjects. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios (HR) of association between baseline hsCRP and NE and colorectal cancer risk. Results: By December 31, 2015, a total of 73 869 participants were enrolled in this study. During the follow-up, 336 incident colorectal cancer cases were identified. All participants were divided into three groups according to the level of hsCRP (<1 mg/L, 1-3 mg/L and >3 mg/L). The cumulative incidence of colorectal cancer were 456/10(5,) 510/10(5) and 746/10(5) in these 3 groups, respectively (χ(2)=10.79, P=0.005). Compared with participants with lower hsCRP levels (<1 mg/L), individuals with the highest hsCRP (>3 mg/L) levels had significant increased risks of colorectal cancer (HR=1.38, 95%CI: 1.05-1.81, P=0.020)after adjusting for age, gender, smoking, drinking, BMI, diabetes and income. Furthermore, subjects were divided into two groups according to the level of NE (≤ 4.08×10(9)/L and > 4.08×10(9)/L). Multivariable Cox proportional hazards regression models indicated that there is no statistical significance of association between NE and colorectal cancer. Conclusions: Elevated levels of hsCRP at baseline might increase the risk of colorectal cancer in males.

[Relation between waist circumference and risk of male lung cancer incidence: a prospective cohort study]

Objective: To investigate the association between waist circumference and risk of male lung cancer incidence. Methods: Since May 1, 2006, all the male employees including the retirees in Kailuan Group had been recruited into a Chinese Kailuan Male Cohort study. Information on anthropometries including body weight, height and waist circumference were collected at the baseline investigation, as well as information on newly-diagnosed lung cancer cases during the follow-up period. Waist circumference was grouped by quintiles of the population waist circumference distribution and categorized into the following five groups: <80, 80-, 85-, 90- and ≥95 cm, with the relevant normal group, the second quintile group (80-cm), serving as the referent category. Multivariable Cox proportional hazards regression models were used to evaluate the association between levels of waist circumference and risk of lung cancer. Results: A total of 105 386 males were recruited in the study, with 739 651.13 person-years of follow-up and an average follow-up period of 7.00 years. By the end of 2014, a total of 707 lung cancer cases were identified in the cohort study. Compared with males having the 80-cm of waist circumference, the hazard ratio (HR) and 95% confidence intervals (CI) of lung cancer were 1.17(0.90-1.52), 0.96(0.74-1.23), 0.94(0.72-1.21) and 0.80(0.63-1.03) for the <80, 85-, 90- and ≥95 cm of waist circumference, after adjustment for potential confounding factors including age, education level, smoking status and pack-year amount, alcohol consumption, physical activities, environment for working place and the prevalence on diabetes. The inverse association existed in smokers (≥95 cm compared to 80-cm of waist circumference: HR=0.69, 95%CI: 0.48-0.99) and alcohol drinkers (≥95 cm compared to 80-cm of waist circumference: HR=0.65, 95%CI: 0.45-0.94) when analysis was conducted in subgroups stratified by smoking or alcohol drinking status. Conclusion: Waist circumference might be inversely associated with male lung cancer risk.

[A prospective follow-up study on the association between serum level of C-reactive protein and risk of digestive system cancers in Chinese women]

Objective: It has been reported by some prospective studies that C-reactive protein (CRP) is associated with cancer risk. However, the correlation between CRP and digestive system cancers has not been evaluated in Chinese females. We conducted a large population-based cohort study to investigate whether elevated level of CRP in serum is associated with an increased risk of digestive system cancers in Chinese women. Methods: From the Chinese Kailuan Female Cohort, 19, 437 women were enrolled in this study in July 2006, and all of the subjects were followed up through 2014. At the baseline investigation, the serum levels of high-sensitivity CRP (hsCRP) were tested for all subjects, and demographic information and risk factor data were collected. Multivariable Cox proportional hazards regression model was used to calculate the hazard ratios (HR) and 95% confidence intervals (95% CI) for the baseline levels of hsCRP after adjusting for age, marital status, smoking, drinking, body mass index (BMI), diabetes and physical activity, and risk of digestive system tumors (including colorectal cancer, stomach cancer, pancreas cancer, liver and gallbladder cancer, and other cancers). Results: By Dec 31, 2014, a total of 100 incident cancer cases were observed, including 47 colorectal cancers, 17 stomach cancers, and altogether 29 pancreas, liver and gallbladder cancers. All the subjects investigated were divided into three groups according to the level of hsCRP (<1 mg/L, 1-3 mg/L and >3 mg/L). The 8-year cumulative incidence of digestive system cancers were 405/100 000, 520/100 000 and 787/100 000 in these 3 groups, respectively (Log rank test χ² = 8.37, P=0.015). Compared to those with lower hsCRP levels (<1 mg/L), the women with higher hsCRP (>3 mg/L) had a significantly increased risk of pancreas, liver and gallbladder cancers (HR = 2.70, 95% CI = 1.06-6.91; P_trend = 0.036). Conclusions: Elevated levels of hsCRP at baseline may be associated with increased risk of certain digestive system cancers.

[Association between body mass index and risk of lung cancer in non-smoking males: a prospective cohort study]

Objective: To assess the association between baseline body mass index (BMI) and risk of lung cancer in non-smoking males. Methods: A dynamic non-smoking male cohort was established on May, 2006. Baseline information on demography, lifestyle, such as smoking status and alcohol consumption, anthropometry, such as body height and weight, were collected during the baseline interview, and the information of newly-diagnosed lung cancer cases were also collected during the follow-up period. Multivariable Cox proportional-hazards regression model was used to analyze the association between baseline BMI and lung cancer in non-smoking males. Results: By December 31, 2011, a total of 48 799 male non-smokers had been assessed in the study and there were 214 620.18 person-years of follow-up and 4.40 years of average follow-up period. During follow-up, 198 lung cancer cases were identified among the 48 799 non-smoking males. Compared with those with normal BMI (kg/m²) (18.5≤BMI<24.0), the hazard ratio (95%CI) of lung cancer were 1.14(0.53-2.45), 0.57(0.41-0.78) and 0.61(0.38-0.97) for underweight (BMI<18.5), overweight (24.0≤BMI<28.0) and obese males (≥28.0), respectively, after adjustment for potential confounding factors, including age, education level, alcohol consumption, physical activity, history of diabetes and work environment. Baseline BMI was negatively associated with the risk of lung cancer in non-smoking males and the risk would be reduced by 22% (HR=0.78, 95% CI: 0.64-0.95) for per 5 kg/m² BMI increase. The negative association between BMI and risk of lung cancer was significant among non-smoking males who aged ≥50 years, and in those who had physical exercise <4 times/week, never drunk and worked above the coal mine, and for per 5 kg/m² BMI increase, the risk of lung cancer would be reduced by 26%(HR=0.74, 95%CI: 0.60-0.92), 24%(HR=0.76, 95%CI: 0.62-0.95), 20% (HR=0.80, 95%CI: 0.65-1.00) and 23% (HR=0.77, 95%CI: 0.61-0.97), respectively. The result was similar after excluding the cancer patients newly diagnose within 1-year and their contribution person years. Conclusion: Baseline BMI might be negatively associated with risk of lung cancer in non-smoking males.

[Body mass index and the risk of lung cancer incidence in smokers: a prospective cohort study]

OBJECTIVE

To investigate the effect of baseline body mass index (BMI) on the risk of lung cancer incidence in male smokers.

METHODS

All the male employees and retirees of the Kailuan Group were recruited in the Chinese Kailuan Male Cohort Study, and they had been experienced routine physical examinations every two years since May, 2006. Up to 31st December 2011, a total of 3 rounds physical examinations had been completed. A total of 42 718 male smokers candidates from the Chinese Kailuan Male Cohort Study were enrolled in the present study. The date of entering this study was defined as that of taking first check-up, and the date of end-of-observation was defined as that of cancer diagnosis, death or end of follow-up (31 December 2011). Information on demographics, lifestyle such as smoking, alcohol consumption, anthropometries such as height and weight, as well as the information of newly-diagnosed cancer cases, were collected at the baseline investigation. Multivariable Cox proportional hazards regression models were used to investigate the association between levels of the baseline BMI and risk of lung cancer.

RESULTS

Of the 42 718 male smokers, there were 181 998.09 person-years of follow-up, taking 4.26 years of average follow-up period. During follow-up, 234 new lung cancer cases were identified among the 42 718 male smokers and the crude incidence density was 128.57/100 000. After the factors adjustment for age, education level, alcohol consumption, physical activity, work environment and cumulative smoking levels (pack-years), compared with subjects of normal BMI group, hazard ratio and 95% confidence intervals of lung cancer for subjects of underweight, overweight, and obesity were 1.63 (0.79-3.37), 0.79 (0.57-1.09) and 0.50 (0.27-0.91), respectively. After the facotors adjustment for age, education level, alcohol consumption, physical activity, work environment and cumulative smoking levels (pack-years), compared with subjects of normal BMI, hazard ratio and 95% confidence intervals of lung cancer for subjects of obesity among subjects who aged 50 years or above, smoked more than 20 pack-years, and exercised less than 4 times per week were 0.33 (0.15-0.71), 0.27 (0.10-0.75), and 0.44 (0.20-0.96), respectively. Obesity subjects who worked above the well had decreased risk of lung cancer (HR=0.38, 95% CI: 0.15-0.96) compared with normal BMI ones who worked above the well.

CONCLUSION

BMI was negatively correlated with the risk of lung cancer in male smokers. As for male smokers, one of the most effective approaches to prevent and control the lung cancer has been shown to quit smoking and keep fit.

1,25(OH)2D3 prolongs islet graft survival by inflammatory inhibition

OBJECTIVE

This study aimed to determine the protective effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) against islet graft loss.

METHODS

Proliferation of tumor necrosis factor (TNF)-α-induced macrophages was determined in vitro after treatment with different concentrations of 1,25-(OH)2D3. Intraportal islet transplantation (IPIT) was performed with islets harvested from the Sprague-Dawley rats and transplanted to the diabetic rats. The transplanted rats were assigned to receive 1,25-(OH)2D3 or propylene glycol (control). Islet graft survival; inflammatory cytokine (TNF-α and interleukin [IL]-1); numbers and percentages of macrophages, CD4(+), and CD8(+) T cells in bloods; and expression of nuclear factor (NF)-κB and TNF-α were analyzed. Hematoxylin and eosin staining was performed.

RESULTS

We found 100 mg/mL 1,25-(OH)2D3 per day to have the strongest inhibitory effect on macrophages. Survival time of islet grafts significantly increased in the rats receiving 1,25-(OH)2D3. There were fewer infiltrated inflammatory cells in both islet graft and adjacent tissue in the drug-treated rats with lower serum IL-1 and TNF-α. Furthermore, percentage of macrophages and expression of p-NF-κB p65 and TNF-α in graft sites were significantly lower in the treated rats.

CONCLUSION

Our results demonstrated that 1,25(OH)2D3 prolongs islet graft survival by decreasing nonspecific inflammation in syngeneic IPIT through inhibiting TNF-α/NF-κB pathway and macrophage infiltration.

Detection of autoantibodies to a panel of tumor-associated antigens for the diagnosis values of gastric cardia adenocarcinoma

To evaluate the diagnostic values of using autoantibodies in sera to a panel of eight tumor-associated antigens (TAAs) of P53, Koc, P62, C-myc, IMP1, Survivn, P16 and Cyclin B1 full-length recombinant proteins for early detection of patients with gastric cardia adenocarcinoma (GCA) and high-risk subjects screening. Enzyme-linked immunosorbent assay was used to detect autoantibodies against the eight selected TAAs in 383 sera samples from four groups, including 140 subjects with normal gastric cardia epithelia (NOR), 76 patients with chronic atrophic gastritis (CAG), 79 patients with gastric cardia dysplasia (DYS) and 88 patients with GCA. In addition, the expression of the eight antigens was analyzed in gastric cardia tissues by immunohistochemical method. The individual autoantibodies to six TAAs (P53, P62, IMP1, Survivn P16 and Cyclin B1) were significantly higher in sera from patients with GCA than that in normal subjects (P < 0.05). When autoantibody assay successively accumulated to seven TAAs (P53, Koc, P62, C-myc, IMP1, Survivn and P16), a stepwise increased detection frequency of autoantibodies was found in the four sera groups (13% in NOR, 39% in CAG, 46% in DYS, and 64% in GCA, respectively), the risks to CAG, DYS and GCA steadily increased about 4.4-, 5.7- and 12.0-fold. The sensitivity and the specificity for autoantibodies against the seven TAAs in diagnosing GCA reached up to 64% and 87%, respectively. The area under the receiver operating characteristic curve for the seven anti-TAA autoantibodies was 0.73 (95%CI: 0.68-0.78) No more increase in sensitivity was found with the addition of new anti-TAA autoantibodies. A combination detection of autoantibodies to TAAs might be helpful to distinguish GCA patients from normal subjects and the patients with gastric cardia precancerous lesions. In addition, further studies in patients with GCA and precancerous lesions using enlarged TAA panels might improve the sensitivity and specificity of cancer detection and high-risk subjects screening.

Decreasing loss of cryopreserved-thawed rat islets by coculture with Sertoli cells

OBJECTIVE

Cryopreserved-thawed rat islets were cocultured with Sertoli cells to examine whether they could decrease the loss and improve islet function.

METHODS

Islets and Sertoli cells were harvested from the pancreas and the testis of Sprague-Dawley rats, respectively. Cryopreserved, stored islets were thawed and divided into groups of coculture with Sertoli cells versus single cells. We measured islets recovery rate and function. Apoptotic-related proteins and gene expressions were detected by Western blot and reverse-transcriptase polymerase chain reaction. Soluble factors secreted by Sertoli cells in to the supernate were detected by enzyme-linked immunosorbent assay. We compared islet graft survival times in diabetic mice.

RESULTS

In contrast to the single culture controls, thawed islets cocultured with Sertoli cells exhibited improved morphology. Recovery rates and insulin secretion were significantly higher among coculture cells. Four soluble factors were detected in supernates from Sertoli cell cultures including transforming growth factor-β, insulin-like growth factor-1, epidermal growth factor, and basic fibroblast growth factor. Expression of proapoptotic Bax and caspase 3, 7 were down-regulated while that of antiapoptotic Bcl-2 was up-regulated. Cotransplantation with Sertoli cells significantly prolonged islet graft survival.

CONCLUSION

These results suggested that coculture with Sertoli cells significantly improved islet yields and function after thawing and depressed islet apoptosis.

Detection and clinical significance of lymph node micrometastasis in gastric cardia adenocarcinoma

OBJECTIVES

Lymph node micro metastasis was investigated in gastric cardia adenocarcinoma (GCA) patients without lymph node metastasis on routine pathological examination. The relationship between micrometastasis and clinicopathological features was also evaluated.

METHODS

A total of 349 lymph nodes were obtained from 45 patients with GCA. Micrometastases were detected by immunohistochemical staining for the markers cytokeratin 19 (CK19) and CD44 variant 6 (CD44v6).

RESULTS

A total of 33 lymph nodes (9.5%) from 15 patients (33.3%) were positive for CK19. Of these, 27 lymph nodes (7.7%) from 12 patients (26.7%) were also positive for CD44v6. Micrometastasis was significantly related to depth of tumour invasion and Lauren classification (intestinal or diffuse). The recurrence rate was significantly higher and 2-year survival rate significantly lower in patients with than in those without lymph node micrometastasis, showing the necessity of detecting micrometastasis in GCA patients who test negative for lymph node metastasis on routine examination.

CONCLUSION

CK19 and CD44v6 were shown to be good markers for micrometastasis detection.

Effects of astragalosides on cultured islets after cryopreservation in rats

OBJECTIVE

To explore the effects of AST (astragalosides) on cultured rat islet yield, purity, and function after cryopreservation in rats.

METHODS

Pancreatic islets were isolated from 30 Sprague-Dawley rats using the standard technique of collagenase P digestion and discontinuous Ficoll gradient purification. After thaw, the islets were randomly divided into AST group and control group (n=15). Next, the islet cells were cultured in AST-containing medium or standard medium for 7, 14, and 21 days after cryopreservation and thaw. The quantity, purity, and survival rate were calculated in the two groups before and after culture. Then the in vitro and in vivo function was observed in diabetic rats after islet transplantation.

RESULTS

The quantity and purity of islets had no difference between the two groups before culture (P>.05) while the difference after culture was significantly (P<.05). The survival rate of islets was 48% in AST group and 32% in the control group 21 days after thaw (P<.05). After 3 days, there was significantly a higher simulation index in the AST group than in the control group (P<.05). There was a significant difference in blood glucose and insulin concentrations between the groups after 3 days (P<.05).

CONCLUSION

AST can be added to the culture medium to reduce the loss of islet cryopreservation and be intravenously injected to improve culture islet function in vitro and prolong islet graft survival in diabetic rats.

Effects of soy isoflavone and endogenous oestrogen on breast cancer in MMTV-erbB2 transgenic mice

OBJECTIVE

Soy isoflavone is associated with modification of breast cancer risk. Effects of dietary isoflavone on breast tissue carcinogenesis under varying endogenous oestrogen contexts were investigated.

METHODS

Five-week-old mouse mammary tumour virus (MMTV)-erbB2 female transgenic mice (n = 180) were divided into three equal groups: low-, normal- and high-oestrogen groups. Each group was then subdivided into an experimental group (given soybean feed) and a control group (given control feed).

RESULTS

In the high-oestrogen environment, breast cancer incidence was significantly lower in the experimental versus the control group, whereas in the low-oestrogen environment, breast cancer incidence was significantly higher in the experimental versus the control group. There were no between-group differences in mean breast tumour latency, mean largest tumour diameter and breast tumour tissue vascular endothelial growth factor levels.

CONCLUSIONS

Dietary soy isoflavones promote breast cancer at low oestrogen levels but inhibit breast cancer at high oestrogen levels. This effect may only occur during the initiation stage of breast cancer.

Energetic electrons associated with magnetic reconnection in the magnetic cloud boundary layer

Here is reported in situ observation of energetic electrons (∼100-500 keV) associated with magnetic reconnection in the solar wind by the ACE and Wind spacecraft. The properties of this magnetic cloud driving reconnection and the associated energetic electron acceleration problem are discussed. Further analyses indicate that the electric field acceleration and Fermi-type mechanism are two fundamental elements in the electron acceleration processes and the trapping effect of the specific magnetic field configuration maintains the acceleration status that increases the totally gained energy.

Improved islet survival and funtion with rat endothelial cells in vitro co-culture

OBJECTIVE

Pancreatic islet transplantation is an emerging therapy for type 1 diabetes. To preserve its function, transplanted islets must be revascularized because arterial and venous connections are disrupted during islet isolation. The current paradigm is that islet revascularization originates from the transplant recipient. This study was designed to test whether the function of isolated islets can be retained by co-culture with thoracic aorta endothelial cells in vitro.

METHODS

Sprague-Dawley rats were used in this study. The endothelial cells (ECs) were isolated from the thoracic aorta. The viability of the isolated islets was assessed by acridine orange/propidium iodide (AO/PI) double staining. The islets were either placed in standard cultures (group A) or in co-cultures with ECs (group B). Islet viablity was assessed by an insulin release assay.

RESULTS

The islets in group B exhibited normal morphology with >90% staining positive as detected by AO/PI with 7 days. Insulin release assays showed a significantly higher simulation index (SI) in group B compared with group A (P < .05) except on the first day.

CONCLUSION

This study suggested that co-cultrue of freshly isolated rat islets with ECs improves postculture survival and islet function in vitro.

Comparative genomic hybridization: comparison between esophageal squamous cell carcinoma and gastric cardia adenocarcinoma from a high-incidence area for both cancers in Henan, northern China

Esophageal squamous cell carcinoma (SCC) remains the leading cause of cancer related deaths in Linzhou (formerly Linxian), the highest incidence area for esophageal cancer (EC) in Henan, northern China. In China, gastric cardia adenocarcinoma (GCA) shares very similar geographic distribution with SCC, suggesting the possibility of similar risk factors involved in SCC and GCA carcinogenesis in these areas. However, the underlying genetic alterations for esophageal and gastric cardia carcinogenesis, especially for the molecular difference between SCC and GCA, are largely unknown. The present study was thus undertaken to determine the difference in chromosomal aberrations in SCC (n = 37) and GCA (n = 31) using the comparative genomic hybridization method (CGH). All the patients were from Linzhou, Henan, a high-risk geographic region for both SCC and GCA. CGH results showed that chromosomal aberrations with different degrees were identified both in SCC and GCA. In SCC, chromosomal profile of DNA copy number was characterized by most frequently detected gains at 8q (29/37, 78%), 3q (24/37, 65%) and 5p (19/37, 51%); and frequently detected losses at 3p (21/37, 57%), 8p and 9q (14/37, 38%). In GCA, the frequently detected gains were identified at 20q (13/31, 42%), 6q (12/31, 39%) and 8q (11/31, 35%); the DNA copy number losses in GCA occurred frequently at 17p (17/31, 55%), 19p (15/31, 48%) and 1p (14/31, 45%). Statistically, there were evident differences between SCC and GCA in DNA copy number gains at 8q, 3q, 5p and 20q (P < 0.05) and in losses at 3p, 8p, 5q, 17p and 18q (P < 0.05). Gains at 8q were frequently observed in both SCC and GCA. Gains at 3q and 8p were frequently observed in TNM stage III of both SCC and GCA. The present CGH results provide candidate regions that may contain specific related genes involved in SCC and GCA in the Linzhou population. Gains at 8q, 3q and 5p and losses at 3p, 8p and 9q were specifically implicated in SCC; gains at 20q, 6q and 8q and losses at 17p, 19p and 1p were specifically implicated in GCA; gains at 8q were implicated in both SCC and GCA.

Effect of leachate recycle and inoculation on microbial characteristics of municipal refuse in landfill bioreactors

Population development of key groups of anaerobic and aerobic bacteria involved in municipal refuse decomposition under laboratory landfill bioreactors with and without leachate recycle and inoculation was measured since modeling municipal refuse was landfilled in bioreactors for about 210 days. Hydrolytic fermentative bacteria (HFB), hydrogen-producing acetogenic bacteria (HPAB), methane-producing bacteria (MPB), sulfate-reducing bacteria (SRB), anaerobic and aerobic cellulolytic bacteria and denitrabacteria were enumerated by the most probable number technique. The results showed that the dominant microorganism groups were the methanogenic bacteria including hydrolytic fermentative, hydrogen-producing acetogenic and methane-producing bacteria. They were present in fresh refuse but at low values and positively affected by leachate recycle and refuse inoculation. The amounts of HFB or HPAB in digesters D4 and D5 operated with inoculation and leachate recycle reached their maximum values of 10(10)-10(12) cells/g dry refuse for HFB or 10(5)-10(6) cells/g dry refuse for HPAB on day 60, in digester D3 operated with leachate recycle on day 120 for HFB (10(9) cells/g dry refuse) or on day 90 for HPAB (10(5) cells/g dry refuse), and in digesters D1 and D2 on day 210 for HFB (10(9) cells/g dry refuse) or on day 90 for HPAB (10(4)-10(6) cells/g dry refuse). The population of methane-producing bacteria in digesters D4 and D5 sharply increased on days 60 and 90 respectively, however in digesters D1, D2 and D3 on day 120. Leachate recycle and inoculation changed the cellulolytic microorganisms composition of refuse ecosystem, the higher amounts of anaerobic cellulolytic bacteria were measured in digesters D4 and D5 (10(7) cells/g dry refuse), followed by digesters D3 (10(6) cells/g dry refuse), D2 or D1(10(4) cells/g dry refuse). However, the amounts of aerobic cellulolytic bacteria were much lower than that of anaerobic cellulolytic bacteria. And it was higher in digester D3 than those in digesters D1, D2, D4 and D5. The amounts of SRB and denitrabacteria were also higher in digester D5 than those in digesters D1, D2, D3 and D4. Refuse decomposition could be accelerated by leachate recycle and inoculation in the view of microorganism development.

[The design of measure and control system for composite treating instrument of gastrointestinal cancer]

This paper introduced a composite method of treating gastrointestinal tract cancer-thermo-chemotherapy. A complete set of intelligentialized real-time measure and control system was well designed. The experiment result showed that this system has a stable performance and good real-time.

Protease-activated receptor 1 (PAR-1) is required and rate-limiting for thrombin-enhanced experimental pulmonary metastasis

Thrombin-treated tumor cells induce a metastatic phenotype in experimental pulmonary murine metastasis. Thrombin binds to a unique protease-activated receptor (PAR-1) that requires N-terminal proteolytic cleavage for activation by its tethered end. A 14-mer thrombin receptor activation peptide (TRAP) of the tethered end induces the same cellular changes as thrombin. Four murine tumor cells (Lewis lung, CT26 colon CA, B16F10 melanoma, and CCL163 fibroblasts) contain PAR-1, as detected by reverse transcriptase-polymerase chain reaction (RT-PCR). B16F10 cells did not contain the two other thrombin receptors, PAR-3 and glycoprotein Ib. TRAP-treated B16F10 tumor cells enhance pulmonary metastasis 41- to 48-fold (n = 17). Thrombin-treated B16F10 cells transfected with full-length murine PAR-1 sense cDNA (S6, S7, S14, and S22) enhanced their adhesion to fibronectin 1.5- to 2.4-fold (n = 5, P <.04), whereas thrombin-treated wild-type cells do not. S6 (adhesion index, 1.5-fold) and S14 (index, 2.4-fold) when examined by RT-PCR and Northern analysis showed minimal expression of PAR-1 for S6 over wild-type and considerable expression for S14. Immunohistochemistry showed greater expression of PAR-1 for S14 compared with wild-type or empty-plasmid transfected cells. In vivo experiments with the thrombin-treated S14 transfectant showed a fivefold to sixfold increase in metastases compared with empty-plasmid transfected thrombin-treated naive cells or S6 cells (n = 20, P =.0001 to .02). Antisense had no effect on thrombin-stimulated tumor mass. Thus, PAR-1 ligation and expression enhances and regulates tumor metastasis.

[Experimental studies of embolization of different hepatotropic blood vessels using Bletilla striata in dogs]

Bletilla striata and gelfoam were used as embolizing agents for the embolization of various hepatotropic vessels in dogs. The results proved that Bletilla striata was superior to gelfoam. The mechanisms of embolization by Bletilla striata are attributable to following factors: non--absobent property, mechanical obstruction; effects on coagulative and anticoagulative systems and secondary obstruction resulted from the injury to wall of blood vessels.

The effect of ligation of portal branch on the growth of implanted tumor of the liver in rats

Small masses of Walker 2 56 carcinosarcoma were implanted into the liver lobe of wistar rats. And at same time, a branch of the portal vein of the involved liver lobe was ligated. After 18 days, the growth of implanted tumor in ligation group was much slower than that in control group, namely, the diameter and wet weight of implanted tumor in ligation group were much smaller and lighter than those in control group. Furthermore, there were no ascites and lung metastases in ligation group. These results suggested that simple ligation of portal branch could apparently inhibit the growth and development of implanted tumor in the liver.

[In vivo antitumor activities of polyethylene glycol modified recombinant interleukin 2 (PEG-rIL-2) against murine hepatoma]

Recombinant human interleukin 2 purified from Escherichia coli has a limited solubility at neutral pH and a short circulatory half-life. This recombinant interleukin 2 was chemically modified by an active ester of polyethylene glycol. The modified interleukin 2 presented in this paper showed an increased antitumor potency in murine hepatoma model, which included prolonging the survival of tumor-bearing mice (from 16.0 +/- 1.8 d to 20.2 +/- 0.9 d, P < 0.01), reducing the lung metastases of hepatoma (from 14.0 +/- 0.7 nodules to 7.5 +/- 1.8 nodules, P < 0.01) and inhibiting the subcutaneous tumor growth (P < 0.01). The results demonstrate that the polyethylene glycol modified interleukin 2 has a higher antitumor activity than unmodified interleukin 2 in vivo and is a potential immunological agent in the adoptive immunotherapy of hepatoma.

Experience with resection of segment VIII of liver for hepatocellular carcinoma

Hepatic segment VIII is located at the dome of the right liver lobe, next to the intrahepatic inferior vena cava (IVC) and is situated between the right and the middle hepatic veins. Its close relation to the IVC inferior medially makes liver cancer resection in this particular segment extremely difficult and hazardous. A personal series of 32 cases of segment VIII resection for hepatocellular carcinoma performed during the period January 1970-May 1992 is being presented. Most resections could be performed with occlusion of the porta hepatis only but some cases required total hepatic vascular exclusion. Since segment VIII is surrounded by major vessels, the extent of resection is limited in this region. Furthermore, tumor cells are easily disseminated along the vascular route. The long-term results are far from ideal. One-, 3-, and 5-year survival rates were 93.33%, 57.14%, and 28.5%, respectively. However, eight patients in this series have survived 180, 168, 104, 78, 53, 43, 43, and 36 months, respectively, and some of them have returned to work. Therefore, despite the technical difficulties involved in segment VIII resection, it is still worthwhile adopting an aggressive operative approach to this group of patients.

Antitumor effects of new-type recombinant interleukin-2

Two new human recombinant interleukin-2 (rIL-2), 125-Ser-rIL-2, and 125-Ala-rIL-2, were generated by protein engineering technique. Both of them maintained the proliferation of natural killer (NK) cells, CTLL-2 cells and their long-term propagations. The mutated new rIL-2 also enhanced the bioactivity of NK cells and the cytotoxicity of tumor-infiltrating lymphocytes (TIL) against the target tumor cells. The above results were all compared with that of the native rIL-2 and a similarity between them was found, which indicates that new type rIL-2 could be used for adoptive immunotherapy of malignant diseases.