Five commonly used traditional Chinese medicine formulas in the treatment of ulcerative colitis:A network meta-analysis

BACKGROUND Currently,traditional Chinese medicine(TCM)formulas are commonly being used as adjunctive therapy for ulcerative colitis in China.Network meta-analysis,a quantitative and comprehensive analytical method,can systematically compare the effects of different adjunctive treatment options for ulcerative colitis,providing scientific evidence for clinical decision-making.AIM To evaluate the clinical efficacy and safety of commonly used TCM for the treatment of ulcerative colitis(UC)in clinical practice through a network metaanalysis.METHODS Clinical randomized controlled trials of these TCM formulas used for the adjuvant treatment of UC were searched from the establishment of the databases to July 1,2022.Studies that met the inclusion criteria were screened and evaluated for literature quality and risk of bias according to the Cochrane 5.1 standard.The methodological quality of the studies was assessed using ReviewManager(RevMan)5.4,and a funnel plot was constructed to test for publication bias.ADDIS 1.16 statistical software was used to perform statistical analysis of the treatment measures and derive the network relationship and ranking diagrams of the various intervention measures.RESULTS A total of 64 randomized controlled trials involving 5456 patients with UC were included in this study.The adjuvant treatment of UC using five TCM formulations was able to improve the clinical outcome of the patients.Adjuvant treatment with Baitouweng decoction(BTWT)showed a significant effect[mean difference=36.22,95%confidence interval(CI):7.63 to 65.76].For the reduction of tumor necrosis factor in patients with UC,adjunctive therapy with BTWT(mean difference=−9.55,95%CI:−17.89 to−1.41),Shenlingbaizhu powder[SLBZS;odds ratio(OR)=0.19,95%CI:0.08 to 0.39],and Shaoyao decoction(OR=−23.02,95%CI:−33.64 to−13.14)was effective.Shaoyao decoction was more effective than BTWT(OR=0.12,95%CI:0.03 to 0.39),SLBZS(OR=0.19,95%CI:0.08 to 0.39),and Xi Lei powder(OR=0.34,95%CI:0.13 to 0.81)in reducing tumor necrosis factor and the recurrence rate of UC.CONCLUSION TCM combined with mesalazine is more effective than mesalazine alone in the treatment of UC.

Ecological Networks of Allometric Growth,Feeding Behavior and Gut Microbiota in Chinese Alligator Hatchlings

Chinese alligator hatchlings in captivity are fragile and have a high mortality rate within first year.The body mass gain of reptile animals is closely related to their feeding behavior and gut microbiota.This study analyzed the intrinsic factors influencing the allometric growth of Chinese alligator hatchlings based on their body mass gain,feeding behavior,and gut microbiota.This information would enhance the health management of Chinese alligator hatchlings.There was a significant correlation between the total distance moved,the average number of conspecifics nearby,and body mass gain.Chinese alligator hatchlings with a greater growth rate showed greater activity and more independent behavior during feeding than those with a lower growth rate.Moreover,after feeding started,some functions of the gut microbiota showed significant relationships with growth rate and feeding activity.Chinese alligator hatchlings with a greater growth rate showed greater levels of heme biosynthesis than those with a lower growth rate,and feeding activity was inhibited by long-chain fatty acid biosynthesis.These results elucidate the relationships between health,feeding behavior,and the gut microbiota of Chinese alligator hatchlings.Understanding the intrinsic factors of their health and feeding behavior can improve the health management of Chinese alligator hatchlings in captivity for conservation.

Comparative efficacy and safety of Chinese patent medicines of iron deficiency anemia during pregnancy:A network meta-analysis

BACKGROUND Iron deficiency anemia(IDA)is a prevalent nutritional disorder during pregnancy.Clinical studies indicate that incorporating Chinese patent medicines(CPMs)with oral iron(OI)in treating IDA in pregnancy can reduce adverse effects and improve clinical outcomes.Nonetheless,the comparative efficacy of different CPMs remains unclear.AIM To assess the safety and effectiveness of different CPMs for treating IDA during pregnancy using network meta-analysis.METHODS We conducted a search for randomized controlled trials(RCTs)that combined CPM and OI for IDA treatment in pregnancy,spanning from 2013 to the present.Data analysis was performed using Rev Man 5.3 and Stata 14.0 on literature that satisfied the quality criteria.RESULTS The analysis included 45 RCTs,encompassing 4422 pregnant patients with IDA.Six CPMs were examined,including Shengxuebao Mixture,Shengxuening Tablets(SXN),Yiqi Weixue CPMs(YQWX),Jianpi Shengxue CPMs(JPSX),Yiqi Buxue Tablets,and Compound Hongyi Buxue Oral Liquid(FFHY).Findings indicated that FFHY+OI significantly improved the clinical effective rate.SXN+OI was most effective in boosting red blood cells counts and hemoglobin levels.YQWX+OI showed superior results in improving serum ferritin,and SXN+OI was most effective in increasing serum iron levels.JPSX+OI was optimal in reducing adverse pregnancy outcomes,while YQBX+OI effectively minimized adverse events.A cluster analysis suggested that SXN+OI could be the potentially optimal therapeutic regimen for IDA in pregnancy.CONCLUSION This study demonstrates that the combination of OI with CPMs offers better outcomes than OI alone.Based on clinical efficacy and other measured outcomes,SXN+OI emerges as the most effective treatment modality for improving the health of pregnant patients with IDA.

A U-Shaped Network-Based Grid Tagging Model for Chinese Named Entity Recognition

Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information extraction.Most previous research has focused on individually studying flat CNER,overlapped CNER,or discontinuous CNER.However,a unified CNER is often needed in real-world scenarios.Recent studies have shown that grid tagging-based methods based on character-pair relationship classification hold great potential for achieving unified NER.Nevertheless,how to enrich Chinese character-pair grid representations and capture deeper dependencies between character pairs to improve entity recognition performance remains an unresolved challenge.In this study,we enhance the character-pair grid representation by incorporating both local and global information.Significantly,we introduce a new approach by considering the character-pair grid representation matrix as a specialized image,converting the classification of character-pair relationships into a pixel-level semantic segmentation task.We devise a U-shaped network to extract multi-scale and deeper semantic information from the grid image,allowing for a more comprehensive understanding of associative features between character pairs.This approach leads to improved accuracy in predicting their relationships,ultimately enhancing entity recognition performance.We conducted experiments on two public CNER datasets in the biomedical domain,namely CMeEE-V2 and Diakg.The results demonstrate the effectiveness of our approach,which achieves F1-score improvements of 7.29 percentage points and 1.64 percentage points compared to the current state-of-the-art(SOTA)models,respectively.

Networking Observation and Applications of Chinese Ocean Satellites

This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural launch in 2002,China has achieved substantial advancements in ocean satellite technology,forming an observation system composed of the HY-1,HY-2,and HY-3 series satellites.These satellites are integral to global ocean environmental monitoring due to their high resolution,extensive coverage,and frequent observations.Looking forward,China aims to further enhance and expand its ocean satellite capabilities through ongoing projects to support global environmental protection and sustainable development.

The Making of a Health Profession:How Chinese Medicine Became a Nationally Registered Allied Health Profession in Australia

In 2012, traditional Chinese medicine(TCM) practitioners in Australia became nationally-registered allied health professionals in three categories: acupuncturist, Chinese herbal medicine practitioner, and Chinese herbal medicine dispenser. Australia was the first Western country to introduce national registration for Chinese medicine, followed by Portugal and, recently, New Zealand. The practice of TCM in Australia can be traced back to the beginning of Chinese immigration to Australia during the Victorian Gold Rush which began in the 1850s. The process which led to national registration commenced in the early 1970s with the establishment of the first acupuncture courses. Decades of gradual development of courses from unaccredited part-time diplomas to accredited bachelor degrees, and the development, by the profession, of national consensus on educational standards were essential elements in the process which led to registration. Professional associations, such as the Australian Acupuncture and Chinese Medicine Association Ltd.(AACMA), also developed a framework of professional selfregulation, including Codes of Ethics, Codes of Conduct, ongoing professional development requirements and Infection Control Guidelines, and provided leadership in the development of the profession. After decades of tribalism and division within the TCM profession, the National Academic Standards Committee brought almost all stakeholders together to reach a consensus on the Australian Guidelines for Traditional Chinese Medicine Education which were published by AACMA in 2001. Professional associations also collaborated on joint submissions to the government in support of registration, which was introduced first in the state of Victoria in 2000, and subsequently became national in 2012. Despite national registration, some barriers still remain, and professional associations continue to lobby the federal government for inclusion in Medicare, chronic disease management scheme, and Veterans Affairs.

An Exploration of How Practitioners Make Meaning in a Chinese Medicine Consultation and Treatment

In Chinese medicine, practitioners assess patients’ complaints, analyze their underlying problems, identify causes and come to a diagnosis, which then directs treatment. What is not obvious and not recorded in a consultation is the clinical reasoning process that practitioners use. The research filmed three practitioners in the UK while they conducted a consultation and treatment on new patients. The practitioners and researchers viewed the films and used them as aide-memoirs while the reasoning process throughout was discussed. In order to determine the pattern, practitioners used the four examinations to gather information from the patient in an iterative process;their aesthetic reasoning was highly developed. Through triangulation they checked the information they received against a detailed understanding of the qi-dynamic. They used highly analytical strategies of forward(inductive) and backward(deductive) reasoning against the prototypes of the signs and symptoms that indicate a specific Zheng. This was achieved through an abductive process that linked description with explanation and causal factors with pathological mechanisms. The feedback loop with the patient continued through the consultation and into the treatment. A process of translation and interpretation was needed to turn the patient’s story into the practitioner’s story of qi-dynamics that then directed the treatment. Awareness of our clinical reasoning process will mitigate against biases, improve our diagnoses and treatment choices and support the training of students.

Cohort study on the treatment of BRAF V600E mutant metastatic colorectal cancer with integrated Chinese and western medicine

BACKGROUND Patients with BRAF V600E mutant metastatic colorectal cancer(mCRC)have a low incidence rate,poor biological activity,suboptimal response to conventional treatments,and a poor prognosis.In the previous cohort study on mCRC conducted by our team,it was observed that integrated Chinese and Western medicine treatment could significantly prolong the overall survival(OS)of patients with colorectal cancer.Therefore,we further explored the survival benefits in the population with BRAF V600E mutant mCRC.AIM To evaluate the efficacy of integrated Chinese and Western medicine in the treatment of BRAF V600E mutant metastatic colorectal cancer.METHODS A cohort study was conducted on patients with BRAF V600E mutant metastatic colorectal cancer admitted to Xiyuan Hospital of China Academy of Chinese Medical Sciences and Traditional Chinese Medicine Hospital of Xinjiang Uygur Autonomous Region from January 2016 to December 2022.The patients were divided into two cohorts.RESULTS A total of 34 cases were included,with 23 in Chinese-Western medicine cohort(cohort A)and 11 in Western medicine cohort(cohort B).The median overall survival was 19.9 months in cohort A and 14.2 months in cohort B,with a statistically significant difference(P=0.038,hazard ratio=0.46).The 1-3-year survival rates were 95.65%(22/23),39.13%(9/23),and 26.09%(6/23)in cohort A,and 63.64%(7/11),18.18%(2/11),and 9.09%(1/11)in cohort B,respectively.Subgroup analysis showed statistically significant differences in median OS between the two cohorts in the right colon,liver metastasis,chemotherapy,and first-line treatment subgroups(P<0.05).CONCLUSION Integrated Chinese and Western medicine can prolong the survival and reduce the risk of death in patients with BRAF V600E mutant metastatic colorectal cancer,with more pronounced benefits observed in patients with right colon involvement,liver metastasis,combined chemotherapy,and first-line treatment.

How Phonetic Is Written Chinese?

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Genetic diversity and matrilineal structure in Chinese tree shrews inhabiting Kunming,China

Due to their special phylogenetic position in the Euarchontoglires and close affinity to primates,tree shrews have been proposed as an alternative experimental animal to primates in biomedical research.However,the population genetic structure of tree shrews has largely remained unknown and this has hindered the development of tree shrew breeding and selection.Here we sampled 80 Chinese tree shrews（Tupaia belangeri chinensis） in Kunming,China,and analyzed partial mtDNA control region sequence variation.Based on our samples and two published sequences from northern tree shrews（T.belangeri）,we identified 29 substitutions in the mtDNA control region fragment（～ 604 bp） across 82 individuals and defined 13 haplotypes.Seventeen samples were selected for sequencing of the cytochrome b（Cyt b;1134 bp） gene based on control region sequence variation and were analyzed in combination with 34 published sequences to solidify the phylogenetic pattern obtained from control region data.Overall,tree shrews from Kunming have high genetic diversity and present a remarkable long genetic distance to the two reported northern tree shrews outside China.Our results provide some caution when using tree shrews to establish animal models because of this apparent genetic difference.In addition,the high genetic diversity of Chinese tree shrews inhabiting Kunming suggests that systematic genetic investigations should be conducted before establishing an inbred strain for medical and biological research.

Genetic Screening of the Lipoprotein Lipase Gene for Mutations in Chinese Subjects with or without Hypertriglyceridemia

Objective： To investigate the association between the mutations in lipoprotein lipase gene and hypertriglyceridemia （HTG）. Methods： The lipoprotein lipase （LPL） gene was screened for mutations in 386 Chinese subjects with （108 cases in the HTG group） or without HTG （278 cases in the control group）, by single-strand conformation polymorphism （SSCP） analysis and DNA sequencing. Results： One novel silent mutation L103L, one missense mutation P207L, three splicing mutations Int3/3＇ -ass/C（-6）→T, and the common S447X polymorphism has been identified in the whole coding region and exon-intron junctions of the LPL gene were examined. Heterozygous P207L found in the HTG group was the first case reported in Asia and subsequently another P207L heterozygote was found in the proband＇s family, all of which suggested that P207L was one of the causes of familial combined hyperlipidemia, but was not so prevalent as that in French Canadian. Int3/3＇-ass/C（-6）→T was found in both groups in the present study although it was regarded as a pathogenic variant to HTG earlier on. Moreover about the beneficial polymorphism S447X, there was also some supportive evidence that the levels of triglycerides （TG） in S447X carriers were significantly lower than noncarders in the subjects without HTG. Conclusions： The association between the LPL variants and HTG is quite complicated and versatile, genotyping of LPL in a larger-scale screening should be necessary and justifiable.

Population genetic diversity and regional differentiation of Chinese forest frog s (Rana chensinensis) in Heilongjiang Province

The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on.

Characterization of Genetic Polymorphism of Novel MHC B-LBⅡ Alleles in Chinese Indigenous Chickens

Genetic polymorphism of the major histocompatibility complex （MHC） B-LBⅡ gene was studied by amplification of exon 2 using PCR, followed by cloning and DNA sequencing in eight indigenous Chinese chicken populations. To reveal the genetic variation of the B-LB Ⅱ gene, 37 types of patterns detected by PCR-SSCP were investigated first, which would be used to screen novel B-LB Ⅱsequences within the breeds. The types of PCR-SSCP patterns and final sequencing allowed for the identification of 31 novel MHC B-LBⅡ alleles from 30 unrelated individuals of Chinese chickens that were sampled. These are the first designators for the alleles of chicken MHC B-LBⅡ gene based on the rule of assignment for novel mammalian alleles. Sequence alignment of the 31 B-LB Ⅱ alleles revealed a total of 68 variable sites in the fragment of exon 2, of which 51 parsimony informative and 17 singleton variable sites were observed. Among the polymorphic sites, the nucleotide substitutions in the first and second positions of the codons accounted for 36.76% and 35.29%, respectively. The sequence similarities between the alleles were estimated to be 90.6%-99.5%. The relative frequencies of synonymous and nonsynonymous nucleotide substitutions within the region were 2.92%±0.94% and 14.64%±2.67%, respectively. These results indicated that the genetic variation within exon 2 appeared to have largely arisen by gene recombination and balancing selection. Alignment of the deduced amino acid sequences of the β1 domain coded by exon 2 revealed 6 synonymous mutations and 27 nonsynonymous substitutions at the 33 disparate sites. In particular, the nonsynonymous substitutions at the putative peptide-binding sites are considered to be associated with immunological specificity of MHC B-LB Ⅱ molecule in Chinese native chickens. These results can provide a molecular biological basis for the study of disease resistance in chicken breeding.

Effects of Ultrasonication on Genetic Transformation via the Pollen-Tube Pathway in Chinese Cabbage

[Objective] This research aimed to explore the method to increase conversion rate of pollen-tub pathway in Chinese cabbage.[Method] Chinese cabbage varieties Yuqing and No.03 were used as materials for the selection of germination buffer and parameters for ultrasonication.[Result] The optimal buffer for pollen germination of Chinese cabbage was 200 g/L sucrose ＋ 100 mg/L boric acid ＋ 200 mg/L calcium nitrate,the preferred ultrasonic processing power was 150 W,processing time was 5 s,interval time was 5 s and processing frequency was 8.Three T1-generation plants were obtained through selection with 200 mg/L kanamycin.[Conclusion] This research laid foundation for the further genetic transformation of Chinese cabbage.

How to Create a Low-anxiety Environment for Chinese Learners of EFL to Enhance Oral Proficiency in Speaking Lessons

The goal of teaching English speaking is to improve students' communicative efficiency, or make students speak the target language clearly, coherently, accurately and fluently (Xu, 2005). However, in China, a number of students in an English speaking class tend to be passive and reluctant to speak out or be singled out publicly mainly due to their high anxiety, which, of course, becomes a significant constraint on improving their English proficiency. Therefore, how to create a relaxed atmosphere with a sense of security in the English speaking class to alleviate Chinese learners' anxiety and to provide them with as many opportunities as possible to practice speaking English and improve their English proficiency is one of the central tasks for language teachers.his paper will firstly outline my teaching context in China in physical, pedagogical, institutional and personal aspects. This will be followed by the definition and classification of language learning anxiety, and the analysis of various factors contributing to foreign language learners' anxiety as well as some suggestions of how to reduce the learners' anxiety in the oral class according to the current literature. Finally, some applications will be presented in my teaching context in the hope of decreasing Chinese students' anxiety to enhance their English speaking proficiency.

English Phonetics Problems under the Chinese Mother-tongue and Dialect Cultures and its Countermeasures

Many people do believe that the pronunciation just related to the phonetic transcription, if we can master it, then we have good pronunciation. However, during the process of language study, we can found that the phonetics is affected by many factors. The consonants problems or vowels problems or during the process of learning, their phonetics is also affected by their mother tongue and local dialect.

Pharmacokinetics of traditional Chinese syndrome and recipe:a hypothesis and its verification(Ⅰ)

AIM To propose a hypothesis defining theabsorption,distribution,metabolism andelimination of traditional Chinese recipe（TCR）-component in blood of healthy subjects andpatients,and estimate its correctness.METHODS The pharmacokinetics（PK）of samedose of drug was studied in the animal model oftraditional Chinese syndrome（S）and healthyanimals.The classification,terminology,concept and significance of the hypothesis wereset forth with evidence provided in the presentstudy.The hypotheses consisted of traditionalChinese syndrome PK（S-PK）and traditionalChinese recipe PK（R-PK）.Firstly,the observedtetramethylpyrazine（TMP）PK in healthy,chronically reserpinized rats（rat model ofspleen deficiency syndrome,RMSDS）andRMSDS treated with Sijunzi decoction（SJZD）forconfirmation were used to verify S-PK; secondly,the ferulic acid（FA）PK in healthy andhigh molecular weight dextran（HMWD）-inducedrabbit model with blood stasis syndrome（RDBSS）was also used to verify S-PK;andlastly,TMP PK parameters in serum of healthyrats after orally taken Ligusticum wallichii（LW）,LW and Salvia miltiorrhiza（LW&SM）decoctions were compared to verify R-PK.RESULTS The apparent first-order absorption[Ka,（13.61±2.56）h-1,area under the blooddrug concentration-time curve[AUC,（24.88±9.76）μg.h-1mL-1],maximum drug concentration[Cmax,（4.82±1.23）μg·mL-1]of serum TMP inRMSDS were increased markedly（P【0.05）compared with those[Ka=（5.41±1.91）h-1,AUC=（5.20±2.57）μg·h-1·mL-1,Cmax=（2.33±1.77）μg·mL-1]of healthy rats（HR）.Theapparent first-order rate constant for α and βdistribution phase[α=（0.38±0.09）h-1,β=（0.06±0.03）h-1,the apparent first-orderintercompartmental transfer rate constants[K10=（0.24±0.07）h-1,K12=（0.11±0.02）h-1,K21=（0.11±0.02）h-1]of serum TMP in RMSDS weredecreased significantly（P【0.01）comparedwith those[K10=（0.88±0.20）h-1,K12=（1.45±0.47）h-1,K21=（0.72±0.22）h-1]of HR.However,no apparent differences occurredbetween HR and RMSDS treated with SJZD.Theserum FA concentration and its AUC[（5.6690±2.3541）μg·h-1·mL-1] in RMBSS were also higherthan those[AUC=（2.7566±0.8232）μg·h-1·mL-1]of healthy rabbits（P【0.05）.The Ka（11.51±2.82）h-1,AUC（0.84±0.17）μg·h-1·mL-1of LW & SM-derived TMP in serum weremuch lower（P【0.05）than those[Ka=（19.58±4.14）h-1,AUC=（1.27±0.26）μg·h-1·mL-1]ofLW-derived TMP in serum after oral decoctions.CONCLUSION The SDS and blood stasissyndrome state could affect significantly thepharmacokinetic parameters of drugs and theabnormal SDS pharmacokinetic parameters couldbe normalized by SJZD.The combination ofChinese medicine in TCR could reciprocallyaffect the pharmacokinetic parameters of othercomponents absorbed into the systemiccirculation.These results support the S-and R-PK hypothesis.

Microsatellite analysis of genetic diversity and population structure of Chinese mitten crab (Eriocheir sinensis)

Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and population structure of the crabs in different water systems, two stocks and two farming populations were assessed with 25 polymorphic microsallite loci available in public GenBank. Basic statistics showed that the average observed heterozygosity （Ho） amongst populations ranged from 0.5789 to 0.6824. However, a remarkable presence of inbreeding and heterozygote deficiencies were observed. To analyze population structure, pairwise FST coefficients explained only -10.3% variability from the subdivision of mitten crab populations, the remaining variability stems from the subdivision within subpopulations. Although the four populations had slight differentiation, different allelic frequencies resulted in distinct population structures. Two stocks and one farming population were clustered together to the phylogenetic branch of Yangtze crab, with an approximate membership of 95%. Whereas, another farming population was clustered singly to the phylogenetic branch of the Liaohe crab, with a membership of 97.1%. The tests for individual admixture showed that Yangtze crab had probably been contaminated with individuals from other water systems. Genetic relationships between populations also supported the conclusion that Yangtze crab and Liaohe crab had different gene pools in spite of the origins of the same species.

An Empirical Study on Chinese City Network Pattern Based on Producer Services

Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China's urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development.

Association between PPARG genetic polymorphisms and ischemic stroke risk in a northern Chinese Han population: a case-control study

Two common polymorphisms of the peroxisome proliferator-activated receptor gamma(PPARG) gene, rs1801282 and rs3856806, may be important candidate gene loci affecting the susceptibility to ischemic stroke. This case-control study sought to identify the relationship between these two single-nucleotide polymorphisms and ischemic stroke risk in a northern Chinese Han population. A total of 910 ischemic stroke participants were recruited from the First Hospital of China Medical University, Shenyang, China as a case group, of whom 895 completed the study. The 883 healthy controls were recruited from the Health Check Center of the First Hospital of China Medical University, Shenyang, China. All participants or family members provided informed consent. The study protocol was approved by the Ethics Committee of the First Hospital of China Medical University, China on February 20, 2012(approval No. 2012-38-1). The protocol was registered with the Chinese Clinical Trial Registry(registration number: ChiCTR-COC-17013559). Plasma genomic DNA was extracted from all participants and analyzed for rs1801282 and rs3856806 single nucleotide polymorphisms using a SNaPshot Multiplex sequencing assay. Odds ratios(ORs) and 95% confidence intervals(CIs) were calculated using unconditional logistic regression to estimate the association between ischemic stroke and a particular genotype. Results demonstrated that the G allele frequency of the PPARG gene rs1801282 locus was significantly higher in the case group than in the control group(P < 0.001). Individuals carrying the G allele had a 1.844 fold increased risk of ischemic stroke(OR = 1.844, 95% CI: 1.286–2.645, P < 0.001). Individuals carrying the rs3856806 T allele had a 1.366 fold increased risk of ischemic stroke(OR = 1.366, 95% CI: 1.077–1.733, P = 0.010). The distribution frequencies of the PPARG gene haplotypes rs1801282-rs3856806 in the control and case groups were determined. The frequency of distribution in the G-T haplotype case group was significantly higher than that in the control group. The risk of ischemic stroke increased to 2.953 times in individuals carrying the G-T haplotype(OR = 2.953, 95% CI: 2.082–4.190, P < 0.001). The rs1801282 G allele and rs3856806 T allele had a multiplicative interaction(OR = 3.404, 95% CI: 1.631–7.102, P < 0.001) and additive interaction(RERI = 41.705, 95% CI: 14.586–68.824, AP = 0.860;95% CI: 0.779–0.940;S = 8.170, 95% CI: 3.772–17.697) on ischemic stroke risk, showing a synergistic effect. Of all ischemic stroke cases, 86% were attributed to the interaction of the G allele of rs1801282 and the T allele of rs3856806. The effect of the PPARG rs1801282 G allele on ischemic stroke risk was enhanced in the presence of the rs3856806 T allele(OR = 8.001 vs. 1.844). The effect of the rs3856806 T allele on ischemic stroke risk was also enhanced in the presence of the rs1801282 G allele(OR = 2.546 vs. 1.366). Our results confirmed that the G allele of the PPARG gene rs1801282 locus and the T allele of the rs3856806 locus may be independent risk factors for ischemic stroke in the Han population of northern China, with a synergistic effect between the two alleles.