Objective To establish a method for the simple and rapid extraction and detection of nitrosodipropulamine(NDPA).Methods NDPA at levels of?g /L grade in chemical industrial wastewater was enriched efficiently using the purge and trap(P&T)method with a Trap3tube under the standard program,including the flow rate of purge gas(40ml/min),the time of purge(11min),the temperature of desorb(225℃),the time of desorb(4min),the temperature of bake(230℃)and the time of bake(10min).The NDPA concentrations were determined by gas chromatography-mass spectroscopy(GC-MS )and chemical ionization(CI )and select ion mode(uSIS)coupled with the purge and trap(P&T)(P&T/GC-MS/CI /uSIS)method Results The detection limit,recovery rates and relative standard deviation(RSD)of the method were3?g /L,62.60%-96.31%and7.5%respectively.The linearity of method was good in the5-30?g /L range with the correlation coefficient 0.978.Conclusion The P&T/GC-MS/CI /uSIS method could be used to detect semi-volatile NDPA in chemical industrial wastewater.

Objective To evaluate the relationship between 5,10-Methylenetetrahydrofolate reductase(MTHFR) gene polymorphisms and colorectal cancer(CRC).Methods Studies were selected based on the criteria for inclusion.The Meta-analysis software,REVMAN 4.2,was applied for checking the heterogeneity across the studies and calculating the pooled OR.The results were evaluated by the analyses of publication bias and sensitivity.Results A total of 9 787 cases and 12 986 controls from 18 studies for C677T and a total of 4 422 cases and 5 819 controls from 9 studies for A1 298C were included.No heterogeneity among the studies was found.For codon 677,the frequencies of CC,CT and TT genotypes were 46.48%,43.81% and 9.71% in cases,and 45.03%,43.08% and 11.89% in controls,respectively.The pooled OR of TT vs.CT+CC was 0.80(95%CI 0.74～0.87).For codon 1 298,the frequencies of AA,AC and CC genotypes were 53.60%,39.39% and 7.01% in cases,and 53.31%,38.67% and 8.03% in controls,respectively.The pooled OR of CC vs.AC+AA was 0.84(95%CI 0.72～0.97).Conclusions MTHFR 677TT is at lower risk of developing CRC and 1 298CC genotypes might be associated with the decreased risk of developing CRC.

Objective To explore the expressions and distributions of glial cell line -derived neurotrophic factor (GDNF)and itstyrosine kinase receptor RET in the terminal rectums of fetal rats with congenital anorectal malfor-mations (ARM)at different gestationalage,and to explore their effects on the enteric nervous system in the terminal rectum of ARMfetal rats.Methods Thirty -five SD pregnancy rats were divided into a saline group (n =1 0)and an ethylenethiourea experiment group (n =25)by simple randomized study.The fetal rats were removed from the pregnant rats at the gestational 1 6 d,1 8 d and 20 d.The fetal rats were divided into the saline control group,the ethylenethiourea control group (fetal rats without ARM)and the ethylenethiourea malformation group (ARM fetal rats)by the naked eye and dissecting microscope.HE staining was used to observe the morphology and the intestinal ganglion cells in the terminal rectum were counted.The immunohistochemical staining and Western blot methods were used to observe the distributions of GDNF and RET in the rectum at the gestational 1 6 d,1 8 d and 20 d.The quantitative real -time poly-merase chain reaction (qRT -PCR)was used to detect the expression of GDNF mRNA in the fetal rats in the terminal rectum at the gestational 1 6 d,1 8 d and 20 d.Results HE staining:the development of anorectal terminal in 3 groups of fetal rats was unclear at the gestational 1 6 d.A small amount of scattered nerve plexuses were observed in the muscu-lar layer.The nuclei were small and sparse.The axons and cytoplasms were less.The serosal layer,muscular layer,sub-mucosa,mucosal layer and glands in the terminal rectum were gradually clear in the saline control group and the ethyle-nethiourea control group at the gestational 1 8 d and 20 d.The intermuscular submucosal nerve plexuses increased gra-dually (1 1 .400 ±3.1 34 and 1 1 .200 ±3.425 at the gestational 1 8 d;66.1 00 ±4.954 and 67.600 ±5.481 at the gesta-tional 20 d).While,the layer was unclear in the ethylenethiourea malformation group and the nerve plexus was less (7.800 ±1 .989 at the gestational 1 8 d,and 25.200 ±3.048 at the gestational 20 d),and the difference was statistical-ly significant compared with 2 control groups (F =7.591 ,271 .833,all P <0.05).Immunohistochemistry satning:the expressions of GDNF and RET in all layers of the intestinal wall in the 3 groups of fetal rats were unclear at the gesta-tional 1 6 d and only a few positive cells were observed.The GDNF and RET were expressed in the mucosal layer and submucosa of the terminal rectum as well as intermuscular nerve plexus in the saline control group and the ethylene-thioured control group at the gestational 1 8 d and 20 d.With the continuous development of the embryo,their expression intensities were gradually increased.The expressions of GDNF and RET positive cells were decreased gradually in the ethylenethiourea malformation group.The difference was significant statistically compared with 2 control groups (all P <0.05).qRT -PCR:the expressions of GDNF mRNA showed no statistical difference among 3 groups at the gestational 1 6 d (P >0.05);the expressions of GDNF and RET protein were 1 03.624 ±27.533 and 1 05.1 84 ±1 9.634 at the ges-tational 1 8 d;1 51 .496 ±33.622 and 1 50.738 ±21 .423 at the gestational 20 d in 2 control groups.Compared with the ethylenethiourea malformation group (79.1 69 ±1 1 .697 at the gestational 1 8 d;94.873 ±1 1 .309 at the gestational 20 d),and the difference were statistically significant (all P <0.05).Conclusions The expressions of GDNF and its tyrosine kinase receptor RET had a certain temporal correlation in the terminal rectum of normal fetal rats at different gestational ages and ARM.Moreover,the abnormal expressions of GDNF and its tyrosine kinase receptor RET in the dis-tal rectum of ARMfetal rats can affect the development of enteric nervous system.

Objective: To investigate the factors influencing the development of gastric cancer in Chinese populations, so as provide insights into creating a model for predicting gastric cancer incidence among Chinese populations. Methods: The case-control and cohort studies pertaining to factors affecting the development of gastric cancer were retrieved in electronic Chinese and English databases, including CNKI, Wanfang Data, VIP, PubMed, Web of Science and Embase from their inception until September 30, 2021. A meta-analysis was performed using R package version 4.1.0. Sensitivity analysis was performed using the “leave-one-out” evaluation procedure, and the publication bias was evaluated using the Egger regression test and the trim-and-fill procedure. Results: A total of 5 301 publications were screened and 116 eligible studies were included in the final analysis, including 103 case-control studies and 13 cohort studies, which covered approximately 3.23 million study subjects. A total of 45 factors affecting the development of gastric cancer were collected, and there were less than 4 publications reporting 7 factors, which were only qualitatively described. There were 38 factors included in the final meta-analysis. A total of 21 factors were identified as risk factors of gastric cancer, including a history of gastrointestinal diseases (pooled OR=4.85, 95%CI: 3.74-6.29), H. pylori infection (pooled OR=3.18, 95%CI: 2.35-4.32), binge eating and drinking (pooled OR=2.88, 95%CI: 2.09-3.97) and a family history of tumors (pooled OR=2.78, 95%CI: 2.17-3.56), and 10 factors as protective factors, including vegetable intake (pooled OR=0.48, 95%CI: 0.38-0.61), tea consumption (pooled OR=0.55, 95%CI: 0.47-0.64), administration of aspirin (pooled OR=0.53, 95%CI: 0.31-0.92) and administration of statins (pooled OR=0.59, 95%CI: 0.44-0.80). Sensitivity analyses of eating moldy food frequently, white meat intake, favoring spicy food and administration of sulfonylureas were not robust. Following correction with the trim-and-fill procedure, there was still a publication bias pertaining to high income, diabetes, administration of stains, alcohol consumption, tea consumption and white meat intake. Conclusions The development of gastric cancer is associated with a medical history of gastrointestinal disease, H. pylori infection, family history of tumors and poor dietary habits. Risk and protective factors of gastric cancer are recommended to be included in models used to predict gastric cancer incidence among Chinese populations.

Objective This study aimed to describe the sex disparities on cancer incidence and mortality in Jiashan population.Methods All data concerning incident and death cases of cancers were gathered from the database of Cancer Registry in Jiashan county.Data from the 2010 China census was used as the standard population.Sex-specific age-standardized incidence rates (ASIRs),mortality rates (ASMRs) per 100 000 persons for all cancers and types of each cancer were calculated for the years of 1990 to 1999,2000 to 2009,2010 to 2014,and 1990 to 2014.In addition,the corresponding male-to-female incidence rate ratios (IRRs) and mortality rate ratios (MRRs) were also calculated.Results The ASIR of all cancers was 226.13/105 for the whole period of 1990 to 2014,with 266.04/105 for males and 187.22/105 for females,respectivcly.The corresponding IRR was 1.42 (95％CI:1.39-1.46),with significant difference noticed in the incidence rates between males and females (P＜0.05).The ASMR of all cancers was 155.39/105,with 206.55/105 for males and 104.98/105 for females,respectively.The corresponding MRR was 1.97 (95％ CI:1.91-2.03),with significant difference between males and females (P＜0.05).Among all the cancer types,only gallbladder cancer and thyroid cancer showed female predominance in both incidence and mortality,with male predominance in all the remaining cancers.Conclusion Finding from our study suggested that a male predominance in both incidence and mortality for a majority of cancers in Jiashan population.

Epidemiology is one of main courses for undergraduate students majoring in preventive medicine.There are some limitations in the traditional epidemiology teaching,which is usually characterized in indoctrinated education:"lectured by the teachers and listened by the students." In Zhejiang University,staff of the epidemiology division tried to explore a new teaching mode as ‘student-centered,teacher-leading,question-based,and combining with literature discussion and course practice.'After practicing for two years,students were inspired in learning initiatives,with teaching effectiveness obviously improved.

This article systematically analyzes the historical evolution of the name， origin， producing area， quality evaluation， harvesting and processing， clinical efficacy of Pyrrosiae Folium by consulting the ancient materia medica， medical books and prescription books， combined with modern literature， in order to provide a reference for the development of famous classical formulas containing this herb. After herbal textual research， it was found that the names of Pyrrosiae Folium in the past dynasties were mostly derived from its color， shape and efficacy. And there were other nicknames such as Shizhe， Shipi and Shilan. Song， Yuan dynasties and before the period， the main origin of Pyrrosiae Folium was Pyrrosia petiolosa， in the Ming dynasty， the main origins were P. petiolosa and P. sheareri， during the Qing dynasty to the present， the main origins were P. sheareri， P. petiolosa and P. lingua. Anciently， the respected Dao-di production area of Pyrrosiae Folium was the area of Lianyungang city， Jiangsu province. In modern times， Anhui and Zhejiang provinces are the main producing areas of P. sheareri， Fujian and Taiwan provinces are the main producing areas of P. lingua， and Guizhou and Hubei provinces are the main producing areas of P. petiolosa. In ancient and modern times， Pyrrosiae Folium with large leaves and thick texture is considered to be the best， the medicinal part is the leaves， and the harvesting and processing methods recorded in the past dynasties were mainly shade-drying after harvesting in the February and July of the lunar calendar， while the modern ones are mostly harvested throughout the year. The processing methods of the past dynasties mainly included removing fuzz by scraping， lightly roasted， frying， fat-fried. However， in modern times， it is mostly used the raw products as a medicine after cleaning， cutting and drying. In ancient times， Pyrrosiae Folium was thought to have a neutral nature with slightly sweet and bitter taste， while in modern times， it is thought to have a slightly cold nature with slightly sweet and bitter taste， and the main effects in ancient and modern times are diuretic， clearing lung-heat， hemostasis and so on. Based on the research results， it is suggested that P. sheareri， P. petiolosa and P. lingua can be used as the medicinal base， processing method can be according to the requirements of formulas， and if the processing requirements are not indicated， the raw products can be selected as the medicine.

In this paper， the name， origin， medicinal parts， producing area， harvesting， processing methods and efficacy of Equiseti Hiemalis Herba（EHH） in famous classical formulas were examined by reviewing related ancient and modern literature. Through textual research， Muzei was first appeared in Zhenyuan Guanglifang（《贞元广利方》）， and used as a mainstream name by later generations. It is also known by other names， such as Cuocao and Bigancao. The main origin of ancient EHH was Equisetum hyemale， which was mixed with E. ramosissimum during the Qing dynasty. The medicinal part was the above-ground part of EHH. In ancient times， the genuine producing area was considered to be Qinzhou， which is now Tianshui city， Gansu. In modern times， EHH produced in Liaoning province is believed to be of higher quality. Currently， the main producing area of EHH circulating in the market is the northeast region in China. EHH with stems that are thick and long， a green color， a thick texture， and clearly visible edges and roughness， but without any easily separating joints being considered the best. The processing methods of the past dynasties mainly included filing， removing knots， stir-baked the crude drugs into black on outside and brown in inside， urine soaking， sun drying and shade drying. In modern times， the main processing method is to first moisturize the plant material， and then cut it into sections before drying. In terms of medicinal properties， EHH is considered by both ancient and modern medicine to have a neutral nature， a slightly sweet and bitter taste， and is non-toxic. Its primary therapeutic effects are related to treating eye diseases， intestinal wind bleeding and uterine bleeding. Based on the research， it is suggested that the dried above-ground part of E. hiemale be used in the development and utilization of famous classical formulas. For the processing requirements are not indicated， it is suggested using raw decoction pieces as medicine， and the processing method refers to the 2020 edition of Chinese Pharmacopoeia. If it is clearly stated that fried charcoal is required， it is recommended to refer to general requirements 0213 of the 2020 edition of Chinese Pharmacopoeia， if it is clearly stated that removing knots is required， it is recommended to follow the ancient method.

To explore the association between particulate matter (PM) and daily hospital visits of coronary heart diseases in Ningbo.Daily data of hospital visits from January 2014 to June 2015 (516 days in total) were obtained from the Yinzhou Health Information System in Ningbo. Daily air pollution data for PM and meteorological data were collected from the database of Ningbo Environmental Monitoring Center and Ningbo Meteorological Bureau. Time-series analysis by quasi-Poisson generalized additive model was used to examine the association between air pollution and hospital visits for coronary heart diseases by adjustment of long-term trends, seasonal patterns and meteorological variables (temperature, humidity), and day of week.An increase of an IQR of PMaccounted for 1.98% (95%:-0.59%-4.63%) increase of hospital visits for coronary heart diseases. The associations between PMand hospital visits for coronary heart diseases among female and the elderly (≥75 years) were stronger (=2.70%,95%:0.01%-5.47%;=3.35%, 95%0.12%-6.69%). The effects of PMattenuated after adjustment for PMPMhad short-term effects on daily hospital visits for coronary heart diseases in Ningbo, and such association was stronger among female and the elderly.
Age Factors ; Aged ; Air Pollutants ; adverse effects ; Air Pollution ; adverse effects ; statistics & numerical data ; China ; epidemiology ; Coronary Artery Disease ; epidemiology ; Female ; Hospitals ; utilization ; Humans ; Humidity ; adverse effects ; Male ; Middle Aged ; Particulate Matter ; adverse effects ; Seasons ; Sex Factors ; Temperature ; Time Factors