Metagenomics ( metagenome) obtained all the microorganisms genome in specific biological environment from DNA samples directly from soil, water and skin, body cavity of human and animals.The metagenomic library was constructed by cloning them into alternative host cells using the vector, which is a discipline of screening new active substances and new genes by high-throughput sequencing.Therefore,using metagenomics not only can effectively detect the composition of microbial community of specific environment,but also greatly expanded the utilize the space of the microbial resources, developed of the next sequencing, enriched the content of bioinformatics. Based on the advantages of metagenomics,we summarized the major advances of metagenomics in human and animal pathogenic microorganisms in recent years,which might be used for the investigation and analysis of microbial pathogens of laboratory animal, animal epidemic monitoring and diagnosis of biological safety.

Objective To study the effect of drinking water at different pH on intestinal microbial diversity in SPF mice.Methods Ninety 21-day-old SPF mice were randomly divided into three groups: drinking acidified water (pH 3.0), neutral water (pH 7.0) and alkaline water (pH 9.0), respectively, for 3 months, 30 mice in each group.10 mice were sacrificed at the end of 4, 8 and 12 weeks in each group.Bacteria, virus and parasites in serum were detected according to the national standard for SPF.Then, primer sequences were designed according to the conservativeness of bacteria 16S rRNA, and libraries were constructed.Subsequently, the ileocecal contents were subjected to high-throughput sequencing (Illumina).10 G data were obtained and analyzed.Results The sequencing results revealed that the intestinal microbial abundance of the mice receiving pH 3.0 drinking water was moderate with a high stability.Conclusions Under the conditions of large-scale breeding, the mice receiving pH 3.0 drinking water can maintain the intestinal microbial diversity for a long time, and reach a stable platform.This study provides theoretical and technical support for the stable long-term maintenance of animal quality production.It is also a specific application of gastrointestinal macrogenomics in animal quality control.

Non-alcoholic fatty liver disease (NAFLD) has become one of the major metabolic diseases.In view of the defects of traditional animal models, this study was the first to establish the NAFLD model of Mongolian gerbil (Meriones unguiculatus) with simple feed formula which is similar to human (from simple fatty liver to steatohepatitis, fibrosis,Liver cirrhosis).This study discussed the mechanism of rapid fatty liver deposition in Mongolian gerbil, revealed its molecular mechanism,main regulatory target and network function of fatty liver susceptibility.We provide a new animal model of NAFLD with relatively clear background and less time-consuming for clinical treatment and new drug development.The theoretical and practical basis for the breeding of inbred strain NAFLD gerbil was established.

Objective To discuss the curative efficacy of locking compression plate (LCP) in the treatment of elderly femoral intertrochanteric fracture. Methods A total of 94 patients with femoral intertrochanteric fracture were assigned to two groups. 29 patients were given DHS internal fixation as DHS group, and 65 patients were given LCP fixation as LCP group. Postoperative hip joint functions in the two groups of patients were assessed. Results There was no signifi-cant difference of general conditions compared between the two groups of patients during the surgery. As for the post-operative complications, LCP group was better than DHS group. As for postoperative Harris curative effects of joint hip and the treatment of A3 type of fractures, the total curative effect in LCP group was better than that in DHS group. Conclusion DHS and LCP are effective internal fixation methods in the treatment of femoral intertrochanteric fracture. They both have merits and demerits. LCP in the treatment of elderly femoral intertrochanteric fracture is better than DHS, and LCP should be the first choice for A3 type of elderly fractures.

Objective To investigate influencing factors of brucellosis infection in occupational population in Gansu Province.Methods In Jingyuan County of Gansu Province,using the case-control method,the cases were collected through "National Disease Surveillance Information Reporting Management System",the case group was confirmed as brucellosis professionals after laboratory tests were positive in 2013-2015 (203 cases),and the control group was confmmed as occupations without brucellosis (809 cases) in the same periods.Information on general sociological characteristics and occupational exposure characteristic was collected,non-conditional Logistic regression analysis was used for analyzing influence factors of brucellosis.Results A total of 1 012 questionnaires were collected,among them,203 were case group and 809 were control group.Logistic regression analysis showed that,captive (OR =1.971,95％CI:1.193-3.256),type of water source (lage,OR =1.610,95％CI:1.392-1.950),often stripping the dead lamb (OR =2.027,95 ％ CI:1.272-3.231),processing abortion material (throwing away,feeding the dog,stripping;OR =2.120,1.176,2.160;95％CI:1.274-3.731,1.148-2.134,1.548-4.671),often eating dead meat (OR =2.497,95％CI:1.438-4.339),Hui nationality (OR =1.202,95％CI:1.061-1.995),household income less than 10 000 yuan (OR =3.857,95％CI:1.593-9.336),work experience 1-4 years (OR =2.892,95％CI:1.838-4.552) were major risk factors for occupational persons suffering from brucellosis.Livestock was sheep or sheep and goats (OR =0.412,0.277,95％CI:0.217-0.782,0.107-0.720),married(OR =0.124,95％CI:0.016-0.979),wearing gloves and mask when exposed to livestock or livestock lambing (OR =0.455,95％CI:0.230-0.899),and livestock vaccination (OR =0.283,95％CI:0.107-0.747) were protective factors for occupational infection of brucellosis.Conclusions The poor living habits and behaviors of professional people in Jingyuan County of Gansu Province are the main causes of the disease.Among them,captive,often stripping the dead lamb,processing abortion material,eating dead meat are the risk factors for brucella infection.Wearing masks and gloves when livestock lambing,and livestock vaccination are important means in avoiding brucellosis infection.

Objective To identify the Brucella strains isolated from sheep blood in Jingyuan County Gansu Province,and to provide scientific basis for Brucellosis control and prevention.Methods In 2016,blood samples from suspected cases of sheep were collected in the home of Brucellosis patient of Jingyuan County,and cultured with vaccination double blood bottles via the enrichment method,and the Brucella strains isolated from sheep were identified by traditional bio-typing,genus specific Brucella surface protein 31 PCR (BSCP31-PCR) and Brucella abortus,Brucella melitensis,Brucella ovis,Brucella suis species-specific PCR (AMOS-PCR),respectively.Results The isolated strain was identified using the traditional biological classification method,bacteria could grow in thionine and fuchsin dyes,A and M factors serum agglutination tests were positive,Bk2 phage lysis test was positive,but Tb and Wb phage lysis tests were negative;and the results of BSCP31-PCR of tested strain was 223 bp band same to Brucella;the results of AMOS-PCR was 731 bp band same to Brucella melitensis.Conclusion Conventional bio-typing test assisted with molecular techniques has confirmed that the isolated Brucella strain from sheep blood is Brucella melitensis type 3 in Jingyuan County Gansu Province.

Objective:To explore the epidemiological characteristics of geriatric hip fractures in Beijing so as to provide evidence for effective prevention and control measures.Methods:This multicenter study was conducted in 3 urban (Beijing Jishuitan Hospital, Beijing Hospital and Beijing Anzhen Hospital) and 3 suburban hospitals (Beijing Shunyi District Hospital, Beijing Changping District Hospital and Beijing Liangxiang Hospital) in Beijing from November 2018 to November 2019. Eligible patients were those aged ≥ 65 years with hip fracture confirmed by X-ray and being admitted to hospital within 21 days of injury. To explore the epidemiological characteristics of geriatric hip fractures in Beijing, such data were collected as patients' age, gender, comorbidities, as well as type, site, time and cause of the fracture.Results:① A total of 2,071 patients were included in this suevey. They were 653 males and 1,418 females (M∶F=1∶2.17). Their age ranged from 65 to 102 years (average, 79.8 years). The patients aged from 75 to 84 years were the most common, accounting for 44.81% (928/2,071). ② Femoral neck fractures accounted for 43.41% (899/2,071), and intertrochanteric fractures accounted for 56.59% (1,172/2,071). The age of the patients with femoral neck fracture was (78.6±7.7) years, which was significantly younger than that of those with intertrochanteric fracture [(80.7±7.4) years] ( P<0.05). ③ 94.69% of the hip fractures (1,961/2,071) were caused by falling, and 71.27% fractures (1,476/2,071) happened at home. ④ Approximately 83.00% of the patients (1,719/2,071) had one or more comorbid conditions. Hypertension was the most prevalent disease (57.89%, 1,199/2,071), followed by diabetes (27.09%, 561/2,071), and coronary atherosclerotic heart disease (22.02%, 456/2,071). Conclusions:In Beijing, significantly more geriatric females sustain a hip fracture than males, and the proportion of those aged from 75 to 84 year is the largest. The proportion of intertrochanteric fractures increases with age. Falls are the leading cause for geriatric hip fractures. Most of the patients have one or more chronic comorbid conditions. Corresponding prevention and intervention measures should be formulated according to the distribution characteristics of elderly hip fractures in Beijing.

Objective To analyze the etiological characteristics of human Brucella strains isolated, and to improve the precision in control and prevention of brucellosis. Methods In 2016, blood samples were collected from patients in Jingyuan County Gansu Province, and tested via the Rose-Bengal Plate Agglutination Test (RBPT) and the tube agglutination test methods,and serological positive blood samples were inoculated to bidirectional blood culture bottle for culturing, and further identified by traditional biological classification method and the Brucella abortus, Brucella melitensis, Brucella ovis, and Brucella suis species-specific PCR (AMOS-PCR). Multiple-locus variable number tandem repeat sequence analysis (MLVA) -16 was used to detect molecular typing and do cluster analysis. Results The isolated strain was identified by the traditional biological classification method, bacteria could grow in thionine and reddened dye, A and M factors agglutination tests were positive, Bk2phage treatment of bacterial strain cracking, but Tb, Wb phages were not cracked. AMOS-PCR amplification result showed a 731 bp band, which was a strain of Brucella melitensis. The results of MLVA-16 showed that there was a difference in the number of repeats on some Variaable Number of Tandem Repeat(VNTR)sites of the isolated strain. Clustering analysis showed that, the isolated strain was clusted into the same clade with the clustering of Brucella melitensis type 3 from GS-201605 in Gansu. And the clustering was similar compared with that of Zhejiang, Guangdong, Fujian and Yunnan. Conclusion Human brucellosis is a inputting transmission in Gansu Province, there is a genetic variation of genotype 3 sheep Brucella between Gansu Province and other domestic provinces.