Objective: To rapidly construct bone-implant complex finite element model series using worksheet-driven CAD and finite element analysis software. Methods: The alveolar ridge and implant models were constructed by CAD software separately. Based on those models, the CAD models of different compositions of cancellous and compact bone and different implants were built and assembled. Electronic form software was utilized to drive the change of dimension in the process. All the models were imported into finite element analysis software and converted to finite element models after installation of different parts in the CAD software. Results: A total of 300 finite element models for different alveoli-implants were obtained through activating different versions of models. The models were of high quality and had no interference with each other. Conclusion: Our modeling method is rapid and highly effective. The series of models basically covers all types of alveoli,which provides a tool for studying the biomechanical characters of implants.

Carcinogens ; Carcinogens, Environmental ; Retrospective Studies ; Threshold Limit Values

Objective To investigate the expression and correlation of hypoxia-inducible factor-1?(HIF-1?),vascular endothelial growth factor(VEGF)and sFlt-1 in the preeclampsia placenta,and discuss their significance in the pathogenesis of preeclampsia.Methods Placentas were collected from 20 pregnant women with preeclampsia as study group and 15 normal pregnant women as control group.The expressions of HIF-1?,VEGF and sFlt-1 protein were semi-quantitatively analyzed with immunohistochemical assay and mRNA level was determined using reverse transcription polymerasc chain reaction(RT-PCR)technique. Results(1)the expression of HIF-1?and sFlt-1 protein in preeclampsia group obviously increased.Strong (+++)positive expression was observed in 9 and 11 cases respectively,significantly higher than in control group(2 and 3 cases)(P＜0.05),however,VEGF expression obviously reduced in preeclampsia group(P＜0.01).(2)the level of HIF-1?and sFlt-1 mRNA in preeclamptic placenta was 0.604?0.013, 0.898?0.041,significantly higher than 0.208?0.007 and 0.559?0.244 in normal placenta(P＜0.05). Although the level of VEGF mRNA increased in preeclampsia placenta,it was not significantly different from that in normal placenta(P＞0.05).The ratio of VEGF mRNA/sFlt-1 mRNA obviously reduced in preeclampsia group and was significantly lower than in control group(P＜0.05).(3)in preeclampsia group,HIF-1?mRNA expression was positively correlated with the expression of sFlt-1 mRNA(r=0.577, P＜0.05),and negatively correlated with the ratio of VEGF mRNA/sFlt-1 mRNA(r=-0.376,P＜0.05).Conclusion Abnormal high HIF-1?expression in preeclampsia placenta indicates that HIF-1?might play an important role in the pathogenesis of preeclampsia,possibly through affecting the cytotrophoblastic invasion and placental vascular reconstruction via the modulation of VEGF and sFlt-1 gene transcription.

· AIM :To investigate the role of pericytes in growth of retinal microvascular endothelial cells with a co-culture system in order to understand some mechanism of angiogenesis in hypoxia induced retinal neovascular disorders.(RMECs) were isolated by a modified protocol using CD31 coated Dynabeads, and identified by immunocytochemical staining with anti-Factor Ⅷ and CD31 antibodies. Rat retinal pericytes were isolated and characterized by immunofluorescent staining with PDGFR-β; and desmin antibodies. Pericytes and RMECs were cultured in a contact co-culture system both under normoxia and hypoxia by Millicell chamber. RMECs proliferation was evaluated by MTT and cell cycle assay with flow cytometry. RT-PCR was used to detect the alteration of KDR/Flk-1 mRNA level in RMECs under normoxia or hypoxia in the co-culture system.harvested with the modified isolating method. The two cell types were identified by positive Factor Ⅷ, CD31 and PDGFR-β, desmin cytochemical staining respectively.RMECs proliferated significantly under hypoxia from 3 to 9d with a maximal rate on day 6 (24.9%, P ＜ 0.01) by MTT. In the co-culture system, the proliferation of RMECs was inhibited by pericytes. After 6d exposure to hypoxia,the fraction of S-phase RMECs number was greatly increased by 43.9% (P ＜ 0.01). In the co-culture system,RMECs proliferation was inhibited by pericytes through decreasing the fraction of S-phase cell number both under normoxia (3.6%, P＜0.05) and under hypoxia (15.1%,P＜0.01). KDR/Flk-1 mRNA level in single cultured RMECs was shown to increase approximately 1.3-fold when exposed to hypoxia. Compared with single cultured RMECs, co-culture with pericytes could decrease KDR/Flk-1 mRNA by 45.1% (P＜0.05) and 27.7% (P ＜ 0.05) under normoxia and hypoxia condition respectively.pericytes could inhibit proliferation of RMECs under both normoxia and hypoxia. The inhibition effects of pericytes maybe, at least in part, due to downregulation of KDR/Flk-1 of RMECs. These findings confirm that pericytes could be a potential inhibitor in the pathogenesis of retinal neovascularization.

Objective To master the implementing progress of preventive measures for control of endemic arsenicosis,to observe the dynamic changes and provide the basis for prevention of national drinking-water-born endemic arsenicosis.Methods The surveillance was strictly carried out according to “The Monitoring Project for the National Drinking-Water-Born Endemic Arsenicosis(trial implementation)” in 2010.According to the results of previous investigation,11 provinces and Xinjiang Production and Construction Corps were selected as the surveillance provinces; eighty six endemic arsenicosis villages which had exposed population over 100 persons were chosen as surveillance villages in each province; forty eight potential endemic arsenicosis villages were recognized as the monitoring villages which had over 100 exposed people too.We investigated the surveillance counties and villages about the running state of water-improving projects,the arsenic content in water from resident house in potential endemic arsenicosis villages and the survey on endemic arsenicosis status based on the residents who lived in the surveillance villages.Results ①Total of 219 water-improving projects in 32 counties were monitored and 1673 villages were covered,benefiting 69.07 million population.②Total of 134 villages with high level of water arsenic were investigated.Water quality improved villages was 86,accounting for 64.18％.Normal working projects accounted for 91.86％ (79/86),intermittentl y working accounted for 4.65％ (4/86) and abandoned projects accounted for 3.49％(3/86).Passing rate of water arsenic of the projects was 91.86％(79/86).Total of 48 villages without water-improving project were investigated,and families with excessive level of water arsenic was 35.04％ (356/1016).③Total of 20 885 persons were examined in villages with improved water,incidence of endemic arsenicosis was 4.44％ (928/20 885).Among them,patients with mild arsenicosis was 3.27％ (682/20 885),with moderate was 0.80％(167/20 885) and serious patients was 0.37％(78/20 885),and detection of skin cancer 1 person.Totally 6166 persons were checked in the villages without water-improvement,incidence of endemic arsenicosis was 3.08％ (189/6166).Among them,mild patients was 2.69％ (166/6166),moderate was 0.28％ (17/6166) and the serious was 0.10％ (6/6166); 20 new cases were diagnosed,and they came from Shanxi province.Conclusions The morbidity in water-improved villages remains higher than the water-unimproved.We should establish and perfect the long-term mechanism of surveillance as soon as possible,and strengthen the management and maintenance of water-improving projects.

Objective To study the role of hematopoietic growth factor(HGF)of placenta chorionic villus in fetal hematopoiesis during embryo ontogeny by observation of the appearance time and the content changes with the fetal growth, which was compared with HGF in cord blood. Methods Thirty embryo villus (2 g each) and 30 cord blood (2 mL each) were collected separately from early pregnant stage(6- 8 weeks), middle pregnant stage(16-22 weeks)and late pregnant stage (37-42 weeks). The levels of HGF were detected by enzyme - linked immunosorbent assay. Results HGF were produced on the early pregnant stage and the content of FL-T3,IL-3 increased gradually.There were significantly differences at different stages(P

OBJECTIVETo study the population structure and ecological distribution of the rhizosperic microorganisms of Angelica sinensis.

METHODThe isolation, culture and identification of microorganisms were studied by the biological methods, and the achieved data were analyzed by the statistical methods for analysis of species diversity.

RESULTWith the growing stages of A. sinensis from Min county of Gansu province, Heqing of Yunnan province and Baoxing of Sichuan province, the quantity of rhizosperic microorganisms increased; and it had reduced since October. In the area of Min county Gansu province, the number ratio of bacteria and fungi was higher than that in the other two areas. In addition, the population diversity and dynamic change were different in three areas. In the area of Min county Gansu province, the number of dominant microbial populations and the population diversities of bacteria, actinomyces and fungi in the rhizosphere were greater than those in the other two areas.

CONCLUSIONThe microecological system and microbial population structure in the rhizosphere of Min county Gansu province were stable. And it was suitable for the growth of A. sinensis in this area.

Angelica sinensis ; microbiology ; Bacteria ; classification ; isolation & purification ; Biodiversity ; Fungi ; classification ; isolation & purification ; Plant Roots ; microbiology ; Soil Microbiology

Objective To evaluate the differentiation-inducing effect of phenylacetate on pancreatic carcinoma cells and underlying mechanism of RNA editing deaminase in cell proliferation and differentiation. Methods The effect of phenylacetate on cell proliferation and cell cycle were investigated in cultured pancreatic carcinoma BXPC-3 cell lines by methylthiazoletetrazolium( MTT) assay, and flow cytometry. The effect of phenylacetate on the expression of RNA editing deaminase (ADAR2 mRNA) in BXPC-3 cells and fresh pancreatic carcinoma specimen was evaluated by RT-PCR. Results ADAR1 mRNA expression was positive in human pancreatic carcinoma tissues and BXPC-3 cell lines. After application of 1.0 and 2.0 mmol/L phenylacetate for 24 h and 72 h, BXPC-3 cell growth inhibition rate increased, G0/G1 phase cells decreased, S phase cells increased, ADAR2 mRNA expression decreased ( P < 0.01 ). Conclusion ADAR2 mRNA played a vital role of regulation in the process of pancreatic carcinoma cells growth and differentiation. Phenylacetate could regulate the proliferation and differentiation of pancreatic carcinoma cells through the regulation of ADAR2 mRNA expression.