Objective To screen antarctic bacteria producing EPA and analyse its composition of fatty acids.Methods Two hundred strains of bacteria were isolated from ice and soil of the Antarctic.The total lipid was extracted by using a modified one-phase Bligh and Dyer extraction,and screened by means of GC using fish oil as standard.In the end,eight strains of bacteria were screened which had high content of EPA or DHA.Among them,one bacterium(NJ136) which had the highest content of EPA was obtained,its total lipid was extracted by means of Soxhlet extractor,and the compositions of fatty acids were analysed by means of GC-MS.Results and conclusion The relative contents of EPA and total unsaturated fatty acids of NJ136 were 6.66% and(51.92%) respectively,the content of total fat,EPA and unsaturated fatty acids of dry bacteria weight were 7.94%,5.3 mg?g~(-1) and 41.2 mg?g~(-1),respectively.

Objective To explore the effect of different cold ischemia (CI) time on the changes of early intragraft cytokines (TNF-α and IL-6) and their correlation with regeneration after small-for-size (30% standard volume) liver transplantation (LT) in rats. Methods A model of Lewis rat 30% standard volume liver transplantation was established. The rats were divided into 3 groups: 1 h CI group, 8 h CI group and 16 h CI group (n= 20 in each group) according to the CI time of donor livers stored in UW solution. Survival rate at day 7 after LT in each group was recorded and specimens were collected at predetermined intervals from 90 min, 1, 2, 4 h and 7 day post-reperfusion. Expression patterns of TNF-αand IL-6 were determined and compared in 30% liver grafts with different CI time following transplantation. Progression of DNA synthesis of hepatocytes was confirmed by BrdU uptake. Morphological assessment of the liver grafts was also made. Results Operative success rate of LT was 100% in all groups. Mean survival rate in 1 h and 8 h CI group was 100% respectively (＞ 7 day). Mean survival rate in 16 h CI group was low, and no recipient animals survived on the postoperative day 7. Compared with 1 h CI group, IL-6 expression in 30% liver grafts stored for 8 h and 16 h was markedly increased post-transplantation (F=184.12, P<0.05). TNF-α expression in 30% liver grafts in 8 h and 16 h CI groups was markedly increased post-reperfusion (F=58.81, P< 0.05). There was no statistically significant difference in the expression of TNF-α and IL-6 between 8 h CI and 16 h CI groups. Number of positively stained nuclei in 1 h CI group was greater than that in 8 h CI group at 24 h after transplantation (t=5.59, P<0.05). At 24 h after transplantation histology showed mild injury in grafts of CI 1 h group. CI 8 h led to mild sinusoidal dilatation and inflammation.Grafts stored for 16 h demonstrated focal congestion, hepatocyte collapse and necrosis. Conclusion At the early stage of small-for-size liver transplantation, up-regulation of cytokines (TNF-α and IL-6) is an important factor in the liver regeneration. The early initiating signals for the regenerative response are present in the small-for-size liver grafts with different CI time.

Objective To explore the molecular mechanisms involved in liver regeneration after different cold ischemic (CI) times for the liver graft in 30% volume rat liver transplantation. Methods A model of 30% volume Lewis to lewis rat liver transplantation with hepatic artery reconstruction was established. Rats were grouped as follows: 1 h CI group (n =25), 8 h CI group (n =25) and 16h CI group (n = 25). Survival rate of rats in each group and liver regeneration were observed. Specimen were collected at predetermined intervals from 90 min, 1,4 and 7 d post-reperfusion. TNF-α and IL-6 expression, STAT3 activation were determined in liver grafts. Expression of cyclin D1 and hepatocyte replication with BrdU uptake were studied by immunohiatochemistry. Statistical analysis was used to compare BrdU positively stained hepatoeytes at 1 d post- reperfusion in each group. Results 30% liver transplantation was performed in a total of 75 rats. Compared with rats in 1 h CI group, TNF-α and IL-6 expression in 8 h CI and 16 h CI groups were markedly increased after 30% liver transplantation. STAT3 activity in 8 h CI and 16 h CI groups was significantly increased. Cyclin D1 expression in 8 CI group was demonstrated with cytoplasmic and nuclear staining. Grafts in 16 h CI group showed large areas with no cyclin D1 expression. Number of hepatoeytes with positively stained neclei in 1 h CI group was more than that in 8 h CI group at 1 d after transplantation (t = 6.14, P < 0.05). Conclusion Liver regeneration following 30% liver graft transplantation may be through TNF-α/IL-6/STAT3/ Cyclin D1/DNA synthesis pathways. The reason for 30% liver graft failure with significant cold ischemic injury is that hepatocytes may not respond to initiating signals for liver graft regeneration.

Objective:To study the influence of occlusal force change on apoptosis of periodontal ligament fibroblast(PDLF) and expression of proliferating nuclear antigen(PCNA) in the fibroblasts,so as to explore the possible mechanism for remodeling of periodontal ligament.Methods:Animal model of occlusal force change was established by extracting the right first,second and third maxillary molars in male SD rats.The rats were sacrificed at 6,12 hours and day 1,2,3,5,7,14,and 28 d after extracting the teeth(n=6),and their alveolar bone tissues were harvested.H-E staining was used to observe the morphologic changes of the alveolar bone tissues.TUNEL method and immunohistochemistry were used to detect apoptosis and PCNA expression in PDLF.The rats with normal occlusal forces were used as control(n=6).The results were assigned a mean score based on the percentage and the intensity of cells positively stained for TUNEL and PCNA.Results:Animal model of occlusal force change was successfully established.H-E staining showed that the control group had more pycnotic periodontal ligament,orderly fibres,and flatter alveolar bone than the model group.TUNEL result showed that the cell apoptosis reached its peak at 12 h after extracting the teeth(252.67?6.62),significantly higher than that of control group(7.17?2.32,P

Objective To observe the effects of intrathymic islet transplantation or renal subcapsule islet transplantation on the graft survival.Methods C57BL/6 mice were used as recipients and BALB/c as donors The recipients receiving intrathymic or renal subcapsule islet transplantation were divided into simple transplantation groups and the group intraperitoneally receiving rabbit antithymocyte serum(ATS) at the time of islet transplantation.Results The median survival time (MST) of simple intrathymic allografts were 19.5 days,longer than that of allografts implanted beneath the renal capsule.Administration of ATS at the time of islet transplantation delayed rejection of islets transplanted to the renal subcapsute(MST,43.0 days),and intrathymic allografts were superior(MST,93.8 days).Six of 8 intrathymic grafts with administration of ATS survived permanently.especially a state of donor-specific unresponsiveness was induced.Conclusion The thymus may be an immunoprivileged site for islet transplantation and may play an important role during the induction of immune tolerance.

Objective To identify the molecular characteristics on nucleotide and amino acid in E gene through the comparative analysis of differences between genotype 3 Japanese encephalitis virus(JEV)in China and the live attenuated vaccine(SA14-14-2).Methods Obtained the E gene nucleotide sequence of Japanese encephalitis virus from GenBank.Multiple alignment and amino acid(AA)analysis were carried out by Clustal X(1.81),DNAStar and GENEDOC(3.2).According to the ribbon diagram of the E protein structure based on the model of the soluble fragment of tick-borne encephalitis virus(TBEV)as a template for Japanese encephalitis virus E protein amino acid sequence analysis.Results Compared different regions and different host genotype 3 JEV with SA14-14-2 the nucleotide sequence homology was,up 96%and 95% and the amino acid homology was up 95%and 94%,respectively.The nucleotide and amino acid homology was higher among the same area and the same host.Ten common amino acid variations and five special variations(E160 in domain Ⅰ,E123 and E227 in domain Ⅱ,E441 and E487 in non-structural domain)were found between genotype 3 JEV and SA14-14-2.Conclusion The homology in E gene was higher between genotype 3 JEV in China and SA14-14-2.Five special amino acid differences were found in genotype 3 JEV.The existing live attenuated vaccine strain is theoretically possible to protect genotype 3 JEV in China.

Tumor is still an unresolved health problem for human.The main obstacle for tumor cure is that precise diagnosis of tumor at the early stage can't be realized,which leads to the mortality increased year by year due to missing the best time of the treatment.Furthermore,lack of targeted ability and serious side effects of the medicine used for tumor treatment also limit the clinical application.Therefore,it is urgent to design and develop a novel targeted drug delivery vehicle.Recent studies show that targeted nanomaterials are superior on tumor-specific diagnosis and target therapy.This review will highlight the current advances in the targeted nanomaterials effect on tumor diagnosis and treatment in recent years and prospect the foreground of future development.

early lithagogue rate.

Objective: To study the influence of occlusal force changes on apoptosis related gene Bcl-2 and Bax in rat periodontal ligament fibroblasts (PDLF). Furthermore, to explore the possible mechanism in remodeling of periodontal ligaments. Methods: Animal model of occlusal force changes was established by extracting the right first, second and third maxillary molars in male SD rats. Rats were sacrificed at 6,12 hours and 1, 2, 3, 5, 7, 14 and 28 days after teeth extraction(n=6), and their alveolar bone tissues were harvested. HE staining was used to observe the morphologic changes of alveolar bone tissues and immunohistochemistry were used to detect Bcl-2 and Bax expressions in PDLF. The rats of normal occlusal forces were used as control(n=6). The results were assigned a mean score based on the expressions and the intensity of cell positively stained for Bcl-2 and Bax. Results: Animal model of occlusal force changes was successfully established. HE staining showed that the control group had more pycnotic periodontal ligament, orderly aligned fibres, and flatter alveolar bone than model group. Immunohistochemical staining showed that expression of Bax reached its peak at 12 h after extracting the teeth(267.00?7.82), significantly higher than that of control group(25.67?4.97,P

14 d).Compared with 1 h CI,TNF-? expressions in whole liver grafts with 8 h and 16 h CI were markedly increased at 90 min after reperfusion(P