Objective Portal hypertension and ischemia/reperfusion (I/R) have been implicated in small-for-size liver graft dysfunction. Matrix metalloproteinases-2 (MMP-2) and MMP-9 are critically involved in hepatic I/R injury. The goal of this study was to investigate the role of MMP-2 and MMP-9 in acute small-for-size graft injury. Methods 108 rats were divided into three groups:100 % (full-size), 50 % (half-size) and 25 % (quarter-size) liver transplantation groups. Blood and liver samples were collected to assess liver function, hepatic malondialdehyde (MDA) content, tissue myeloperoxidase (MPO) activity and histological changes. ELISA, real-time PCR, gelatin zymography, and immunohistochemistry were used to determine the expression pattern of MMP-2 and MMP-9 in liver grafts. Results The expression levels of MMP-9 were significantly higher in quarter-size and half-size grafts than those in full-size liver grafts 6, 12, and 24 h after reperfusioa And theelevated levels of MMP-9 were related to graft size inversely. However, MMP-2 was expressed and remained in all groups invariably. MMP-9 overexpression was accompanied by extensive liver I/R injury, as evidenced by significant increases in hepatic microscopic damage scores, MDA content,MPO activity and liver function levels. Furthermore, MMP-9 was found mainly to locate around periportal area. The presence of the active form of MMP-9 was significantly higher in small-for-size grafts, which was correlated with sinusoidal dilatation, congestion and hemorrhage. Conclusion These results support critical function of MMP-9 in acute small-for-size liver graft injury. Moreover,portal hypertension may be a crucial trigger for expression and activation of MMP-9.

Objective To compare the value of ERCP plus EST and laparotomy in the treatment of common bile duct stones.Methods 56 cases of common bile duct stones were treated with ERCP and EST in our hospital from June 2012 to June 2013 (endoscopy group),78 cases were treated with laparotomy and common bile duct exploration (laparotomy group).The two groups were compared on success rate of stone removal,operation time,intraoperative bleeding volume,incidence of infection and pancreatitis and hyperamylasemia,common bile duct stone recurrence rate,hospital stays,hospital costs.Results Operation time,intraoperative bleeding volume and infection rate in endoscopic group was lower than the laparotomy group,the incidence of hyperamylasemia,hospital costs in the endoscopic group was higher than laparotomy group.The success rate of stone removal and the recurrence rate of common bile duct stone in the endoscopic group was lower than the laparotomy group,incidence of pancreatitis in the endoscopic group was higher than the laparotomy group,though the differences were not statistically significant.Conclusions ERCP and EST is a time saving procedure fast relieving the bile duct obstruction,less traumative,spelling lower infection rate,less hospital stays,though causing higher incidence of hyperamylasemia and hospital costs.

BACKGROUND: Our former studies have shown that bone marrow mesenchymal stem cells (BMMSCs) can be induced differentiation to vascular smooth muscle-like cells (VSMLCs) and vascular endothelium-like cells (VELCs), which are compatible with collagen-embedded polyglycolic acid scaffolds. OBJECTIVE: To investigate the possibility of constructing small diameter tissue-engineered blood vessels via subcutaneous implantation. METHODS: The cells-scaffold complex was produced by separately seeding VSMLCs and VELCs derived from BMMSCs on polyglycolic acid collagen scaffolds. The two layers were separated by ECMgel. The cells-scaffold complex was subcutaneous implanted into small diameter tissue-engineered blood vessels.RESULTS AND CONCLUSION: Histological analysis of the small diameter tissue-engineered blood vessel walls revealed a typical artery structure, which was similar to natural vessels. The tissue-engineered blood vessels were not broken down under a force of 26.6 kPa. Eight weeks after implantation, the Brdu-labeled seed cells were found in the three layers of the vessel walls. The results revealed that the subcutaneous tissue was a good bioreactor to construct small diameter tissue-engineered blood vessels.

Purpose To investigate the relevance between the expression of miR-339-5p and the clinicopathological characteristics in diffuse large B-cell lymphoma (DLBCL). Methods The level of miR-339-5p expression was detected in 123 cases of diffuse large B-cell lymphoma tissues and 20 cases of reactive lymphoid hyperplasia tissues by chromogenic in situ hybridization ( CISH) technique. The expression of Ki-67 and BCL-6 protein was examined in diffuse large B-cell lymphoma tissues by immunohistochemical technique (IHC) (EnVision two-steps), and the correlation between the expression of miR-339-5p and BCL-6 and the clinicopathological param-eters was also analyzed. Results The positive rates of miR-339-5p were 39. 8% (49/123) in DLBCL tissues, which was significantly lower than that in RH tissues (90%, 18/20). The positive rates of miR-339-5p were 31. 0% (22/71) for germinal center B-cell-like (ABC type) DLBCL, which was significantly lower than that in activated B-cell-like (GCB type) DLBCL (27/52, 51. 9%). The low-er expression of miR-339-5p in DLBCL was correlated with late Ann Arbor staging and high-risk group of international prognostic index (P<0. 05). The survival rates of miR-339-5p negative patients of ABC type and GCB type of DLBCL were significantly lower than that of the positive patients (P<0. 01). The levels of miR-339-5p expression in DLBCL were negatively correlated with the levels of BCL-6 expression in DLBCL (P<0. 01). Conclusion The low expression of miR-339-5p might be relatived with the progression and poor prognosis of DLBCL.

Objective: To quantitatively compare five occupational health risk assessment models in assessing silica dust hazard risk in small open pits, so as to provide the reference for the research of occupational health risk assessment methodology Methods : Seven small open pits were selected as the evaluation sites. The models from Singapore, the United Kingdom's Control of Substances Hazardous to Health Essentials ( COSHH Essentials ), Australia, Romania, and the International Council on Mining and Metals ( ICMM ) were applied to assessing the occupational health risk of the workers exposed to silica dust. The risk ratios ( RRs ) were calculated, and the parallelism, accuracy and correlation of the evaluation results of the five models were compared. Results : The RRs of the Singaporean model, COSHH model, Romanian model, Australian model and ICMM model were 0.8, 1.0, 0.4, 0.6 and 0.8, respectively. The Singaporean model and the Australian model were able to distinguish transport drivers from sprinkler drivers in the health risk exposed to silica dust, which was consistent with the actual risk of the two posts. Except for COSHH model, the RRs of the other four models were positively correlated ( P<0.05 ); the RRs were all positively correlated with concentration ratios ( CRs ) ( P<0.05 ), and the correlation coefficient between RRs and CRs of the Singaporean model was the largest (0.801). Conclusion Among the five models, the Singaporean model can more accurately evaluate the hazard risk of silica dust in posts of open pits, and has a good correlation with the other models.

VEGF nanoparticle (VEGF-NP) was prepared by a multi-emulsification technique using a biodegradable poly-dl-lactic-co-glycolic (PLGA) as matrix material. The nanoparticles were characterized for size, VEGF loading capacity, and in vitro release. VEGF-NP and naked VEGF plasmid were intramuscularly injected into the ischemia site of the rabbit chronic hindlimb ischemia model and the efficiency of VEGF-NP as gene delivery carrier for gene therapy in animal model was evaluated. Gene therapuetic effect was assessed evaluated by RT-PCR, immunohistochemistry and angiography assay. The average size of VEGF-NP was around 300 nm. The encapsulation efficiency of VEGF was above 96%. Loading amount of VEGF in the nanoparticles was about 4%. In vitro, nanoparticles maintained sustained-release of VEGF for two weeks. Two weeks post gene injection the capillary density in VEGF-NP group (81.22 per mm2) was significantly higher than that in control group (29.54 mm2). RT-PCR results showed greatly higher VEGF expression in VEGF-NP group (31.79au * mm) than that in naked VEGF group (9.15 au * mm). As a carrier system for gene therapy in animal model, VEGF-NP is much better than naked DNA plasmid. The results demonstrate great possibility of using NP carrier in human gene therapy.
Animals ; Disease Models, Animal ; Gene Transfer Techniques ; Genetic Therapy ; Genetic Vectors ; chemistry ; Lactic Acid ; chemistry ; Nanoparticles ; chemistry ; Plasmids ; Polyglycolic Acid ; chemistry ; Rabbits ; Vascular Endothelial Growth Factor A ; genetics

Objective:To investigate and analyze the radioactivity levels of 90Sr and 137Cs in drinking water and 137Cs in food after the installation of the first AP1000 nuclear power unit in China. Methods:From 2012 to 2019, four drinking water monitoring points around AP1000 nuclear power unit located at Sanmen nuclear power plant site were collected during the wet season and dry season, 90Sr and 137Cs and radioactivity concentrations were determined in drinking water. Local rice, cabbage, crucian and mullet were collected to determine the radioactivity concentration of 137Cs. Results:From 2012 to 2019, the radioactivity concentrations of 90Sr and 137Cs in drinking water were 1.2-9.8 mBq/L and 0.2-8.1 mBq/L, respectively. The radioactivity concentration of 137Cs in food were 1.1×10 -2-2.8×10 -1 Bq/kg, lower than the limits specified in the Limited concentrations of radioactive materials in foods (GB 14882-94). Conclusions:After the installation of the first AP1000 nuclear power unit in China, the radioactivity levels of 90Sr and 137Cs in drinking water and 137Cs in foods are stable, without environmental impact identified.

Objective:To investigate the levels of gross radioactivity in drinking water and of 90Sr in food around Sanmen nuclear power plant (NPP) before and after operation. Methods:From 2012 to 2019, 7 drinking water monitoring sites were selected around the Sanmen NPP to collect source water, factory water and peripheral water, respectively, in order to measure and analyze the total radioactivity level in drinking water. Based on the dietary habits of local residents, 4 kinds of food such as grains, vegetables, freshwater fish and marine fish grown locally were sampled to measure and analyze the activity concentration of 90Sr. Results:Before the operation of Sanmen NPP, the total α radioactivity and total β radioactivity in drinking water around the NPP were 0.001-0.063 Bq/L and 0.019-0.210 Bq/L, respectively. After operation, the total α radioactivity and total β radioactivity were 0.001-0.084 Bq/L and 0.025-0.079 Bq/L, respectively. Both were lower than the national standard value given in the GB 5749-2006 " Sanitary standards for drinking water" . There was no significant change in the radioactivity level of source water, factory water and peripheral water during the wet and dry periods. The activity concentration of 90Sr in these four types of food ranged from 0.037 to 1.216 Bq/kg before operation and from 0.049 to 0.692 Bq/kg after operation, all lower than the standard value of " Standard for the concentration in radioactive substances in food" (GB 14882-94). Conclusions:Before and after the operation of Sanmen NPP, the total α and total β radioactivity in drinking water and 90Sr activity concentration in food are stable, below the national standard limit.

Objective: To investigate the epidemiological characteristics of norovirus clustering and outbreaks in schools and kindergartens in China, so as to provide references for prevention and control of outbreaks. Methods: A descriptive epidemiological method was used to analyze outbreaks of Norovirus in schools and kindergartens in China during 2014-2018 , the indicators which was analyzed and compared including attack rate, duration of the outbreak, reporting interval. Results: A total of 832 Norovirus outbreaks were reported by schools and kindergartens in China from 2014 to 2018. The total number of outbreaks showed an upward trend with an average annual growth rate of 58%. The number of reported cases was 40 445 but there was no death. Norovirus outbreaks mainly occurred in primary schools (42%), followed by kindergartens and middle schools (both 24%), university (6%) and 77 outbreaks (4%) were reported in universities and other schools. The peak seasons were March to May, November and December each year. Jiangsu Province and Guangdong Province (both 22%) reported the largest number of outbreaks. The main transmission of norovirus outbreaks was through direct person contact (72%), foodborne (4%) and waterborne (3%) caused fewer outbreaks than direct person contact. The duration of the epidemic was positively correlated with the reporting interval (r=0.63, P<0.05) and the number of cases per outbreak (r=0.51, P<0.05). Conclusion Disinfection treatment of vomitus should be standardized in schools and kindergartens. Timely detection, reporting, disposal of the epidemic can effectively control the spread of norovirus outbreaks.

OBJECTIVE： To analyze the effect of the national designated production pilot policy for drug in shortage in China. METHODS： Taking 2 batches of drugs from 7 designated production manufacturers in Chongqing from Sept. 2012 to Sept. 2018 as an example， the overall supply situation of designated production （using the average satisfaction rate of medical institution’s order as index）， the changes of drug supply （average satisfaction rate of order） before and after the implementation of national designated production policy （during designated production period and non-designated production period） were all analyzed. According to the level of medical institutions and the order quantity of medical institutions （three sections： small amount， suitable， big amount）， the classification analysis was carried out. At the same time， telephone interview was conducted among the business personnel of related pharmaceutical production enterprises to understand and summarize the reasons for the supply problems of these drugs. RESULTS： Except for the average satisfaction rate of drug order was 0 in one designated production manufacturers， the satisfaction rate of drug order in the other 6 designated production manufacturers ranged from 58.05％ to 92.31％. During the designated production period， the satisfaction rate of drug order was increased significantly， compared with non-designated production period. However， after the expiration of the designated production of drugs， the order satisfaction rate mostly declined， and satisfaction rate of some drug orders were even lower than that before designated production. Average satisfaction rate of drug order in third level medical institution was higher than those of second level， first level or primary medical institutions. During designated production period， the average satisfaction rate of drug order in designated production manufacturers to medical institutions at all levels was higher than during non-designated production period or in non-designated production enterprises. There are 5 kinds of reasons for supply problem of designated production and drug with same specification： the limited price is lower than the cost； the production is stopped due to raw material； the production is stopped because of enterprise； the medical insurance payment price is far lower than the supply price； the hospital demand is small. CONCLUSIONS： The designated production pilot policy has played a significant role in improving the shortage of drug supply， but it still needs to be improved by establishing a dynamic adjustment mechanism for the scope， price and duration of designated drug production.