The diversity in Tibetan kefir grains and dynamics of the microbial community during the fermentation of Tibetan kefir by PCR-DGGE fingerprinting technique were studied.The results showed that bacterial community of Tibetan kefir grains was more complex than that of yeast.The bacteria communities between different Tibetan kefir grains showed 78%～84% similarity, and yeast 80%～92%.Bands B, E and N of DGGE profiles of the microbial community during fermentation of Tibetan kefir were present throughout the fermentation.Analysis of sequence date showed the majority of the DGGE bands of bacteria community corresponded to LAB, and the most intense band (band E) was completely homology to Lactococcus lactis.

AIM: To study p42/p44 mitogen - activated protein kinases ( MAPK ) signal transduction pathway effect on vascular endothelial growth factor ( VEGF ) expression induced by elevated glucose concentration in cultured human retinal pigment epithelium ( hRPE) .
METHODS:hRPE cells were cultured and divided into four groups:normal glucose group (NG) (5. 6mmol/L), high glucose group ( HG1:15mmol/L D-glucose, HG2:20mmol/L D - glucose, HG3:30mmol/L D - glucose ), PD98059 group: hRPE cells were treated by an efficient and selective inhibitor PD98059 (20μmol/L) of p42/p44MAPK signal transduction pathway and solvent dimethyl sulfoxide group ( DMSO group) . The expression of VEGF and pigment epithelium derived factor ( PEDF ) mRNA was detected by RT-PCR. VEGF protein expression in cultured hRPE supernatants was detected by enzyme-linked immumosorbent assay ( ELISA) .
RUSULTS: VEGF mRNA and protein expression induced by elevated glucose concentration increased significantly. VEGF mRNA and protein expression were restrained in PD98059 group. Ratio of ( VEGF/β-actine)/( PEDF/β - actine ) in PD98059 group decreased significantly compare with that in high glucose group.
CONCLUSION: p42/p44MAPK signal transduction pathway might play a part in VEGF expression induced by elevated glucose concentration in cultured hRPE cells.

Objective To construct an expression system to produce the virus-like particles containing a part of the sequence of PSA mRNA, which are ribonuclease-resistant due to the encapsulation of the mRNA by bacteriophage MS2 coat proteins. Methods The PCR products of PSA cDNA fragments were cloned to TA vector pBS-T, then the targeted segments could be obtained when the pBS-T-PSA were digested by restriction endonuclease Hind Ⅲ and cloned to prokaryocytic expression vector pNCCL1. The recombinant plasmids named PNCCL1-PSA were transfected into E. Coli BL21-DE3 and induced to express with IPTG. Results The recombinant plasmids were successfully constructed. The bacteriophage MS2 coat protein which expressed in BL21 can self- assemble to form ribonuclease resistant virus-like particles and the PSA mRNA was encapsulated into virus-like particles. Conclusions The virus-like particle containing PSA mRNA can be expressed in prokaryocyte and it can be used as standard and control in detecting PSA mRNA. It provides a new, stable and ribonuclease-resistant RNA standard in RNA detection.

Objective:To evaluate the clinical application of 64-slice spiral computer tomography pulmonary angiography (CTPA)in diagnosis of pulmonary embolism(PE).Methods:Sixty-two patients suspected of PE were examined by 64-slice spiral CTPA.The image findings combined with their clinical data were retrospectively analyzed.Results:Twenty-four of the 62 patients were confirmed to have PE by clinical data,laboratory examination and follow-up examination.64-slice spiral CTPA discovered 152 involved branches in the 24 PE patients,including 4 branches in left and right pulmonary trunk,52 in lobar pulmonary arteries,82 in segmental pulmonary arteries,and 14 in subsegmental arteries.Four types of PE were detected in our group,including eccentric filling defect in 58 branches,central filling defect in 49 branches,total occlusion of the pulmonary arteries in 21 branches,and mural embolism of host artery in 24 branches.The diagnosis accuracy of 64-slice spiral CTPA in the present group of patients was 100%,with no missed diagnosis and misdiagnosis.Besides,64-slice spiral CTPA could reflect the location,morphology,involvement and degrees of PE.Conclusion:64-slice spiral CTPA is a rapid,accurate and non-invasive diagnostic approach for PE.It is the first choice in clinical screening of PE and may serve as a gold standard for diagnosis of pulmonary embolism.

Mycelial morphology are exploited a great influnence to the metabolites of fungi. The effect of the mycelial morphology on producing lycopene by Blakeslea tripora was investigated. The results indicated that pellets has little role on fermentation when adding kerosene and triton-x100, However, The content of lycopene in the medium reached to 98.6mg/L by adding Ig/L span-20, forming dispersed mycelia, which is 3 times of the control experiments.

To examine the effects of heterologous expression of ZrGPD1 (encoding glycerol 3-phosphate dehydrogenase ) cloned from osmotolerant yeast Zygosacharomyces rouxii on glycerol production in wild Pichia farinosa,the URA3 gene was amplified from P. farinosa as the homology integrative region. A recombinant plasmid (pUR-ZG) was constructed then transformed into P. farinosa by electroporation. The transformant pfa-gu was obtained by the selectable marker Zeocin TM . Primary results showed that the biomass of pfa-gu was higher than the wild type in the flask and after 72h fermentation the concentration of glycerol of pfa-gu was 37g/L enhanced 30% in comparison with the wild type. It is concluded that heterologous expression of ZrGPD1 is useful for increasing glycerol production and the ability of osmoregulation in P. farinosa.

In industrial glutamate fermentation, intermitted feeding glucose with the help of off-line glucose measurement is generally necessary. This kind of feeding strategy could cause large variations in glucose concentration so that it is not favorable for the achievement of efficient and stable glutamate fermentation. Glutamate fermentation is characterized with typical non-growth association behavior, and during glutamate production phase glucose consumption is closely correlated with ammonia consumption. In this study, glucose concentration was controlled at various pre-determined levels by predicting glucose consumption amount and thus its concentration with the aid of on-line monitoring ammonia consumption. When glucose concentration was controlled around a lower level of 5 g/L~10 g/L, the final glutamate concentration could reach a relatively higher level of 80 g/L. In this way, the huge osmotic stress change due to the large glucose concentration variation with the intermitted feeding method could be avoided and the glutamate fermentation performance enhancement be expected.

The role of general practitioners in the UK was analyzed and we found that in the UK, there was normalized general medical education system, perfect general practitioner training sys-tem, specific responsibilities and assessment index, close liaison group between primary and secondary care, strong economic supporting measures and high degree of recognition. Therefore, to deepen med-ical reform and improve basic medical service, we must accelerate general practitioners training, im-prove practice ability of general practitioners, establish the first-treatment system in community, reit-erate role of gatekeeper, enhance the payment of general practitioner and increase their sense of iden-tity. At the same time, we must strengthen the informatization construction, set up the first-treatment in the community and the patency of two-way referral system.

Objective To analyze the pathological and clinical characteristics of patients with idiopathic IgA nephropathy accompanied by vasculitic/crescentic lesion (IgA-V/C). Methods Data of 222 patients diagnosed as idiopathic IgA nephropathy by renal biopsy, among them 87 cases with vasculitic/crescenlic (V/C)lesion, from our department in 2004 were analyzed retrospectively. Clinical and pathological data from patients with IgA-V/C were compared to those of non-IgA-V/C patients and of lupus nephritis (LN) patients with V/C lesion. Results Vasculitic/crescentic lesion was found in 39.19% (87/222) patients with idiopathic IgA nephropathy.And about( 14.08?12.75)% of the glomeruli was affected. It should be taken into account that there was no significant differences of clinical manifestations including blood pressure, urinary protein excretion between IgA-V/C group and non-IgA-V/C group .except serum creatinine(Scr)level which was significantly higher in IgA-V/C group. In addition, only 37.9% of IgA-V/C patients presented high Scr level,thus the lesion of V/C in idiopathic IgA nephropathy was easily overlooked. Patients with idiopathic IgA nephropathy were found to have higher percentage of glomerular sclerosis (64.86% vs 40.00%) and ratio of sclerostic glomeruli to total glomeruli [ (26.98 ?24.68)% vs (16.10 ?18.80)% ]as compared to LN group, which further predicated the progressing characteristics of IgA nephropathy. Conclusions Vasculitic/crescentic lesion is a quite common finding in idiopathic IgA nephropathy and often associated with no dramatically symptoms. It is possible for vasculitic/crescentic lesion to induce unmarked lose of nephron slowly and continually, so as to accelerate IgA nephropathy progression to end-stage renal failure.

Objective To determine the correlation between mouse maerophage metalloelastase (MME)and vascular endothelial growth factor(VEGF)expression involved in angiogenesis of colon cancer.Methods A eDNA fragment coding for domainsⅠandⅡof MME was transfected into murine CT-26 colon cancer cells that were MME deficient.The enzymatic activity of recombinant MME was confirmed by cleavage of native substrate in vitro.An orthotopic implantation model was established by using MME-transfected cells and control cells.Tumor samples were subjected to in situ hybridization (ISH)and immunohistochemical staining(IHC)to detect expressions of MME and VEGF.The microvessel counting was used to assess angiogenesis of murine colon tumors.Results It was demon- strated that the tumor growth was significantly inhibited in MME-transfected group compared with pcDNA3.1 transfected and nontransfected groups(P＜0.001).It was also found that,compared with pcDNA3.1-transfected and nontransfected groups,the microvessel formation in MME transfected group was significantly reduced(P＜0.001).The expression of VEGF mRNA and protein was significantly lower in MME-transfected group than those in the controls,as demonstrated by ISH(MME-transfected group versus pcDNAa.1-transfected group,P=0.028;and versus nontransfected group,P=0.003) and by IHC(MME-transfected group versus pcDNA3.1-transfected group,P=0.025;and versus non- transfected group,P=0.008).Conclusions The MME gene transfected into murine colon cancer cells can effectively suppress the growth of orthotopic tumors by inhibition of vaseularity.Both MME and VEGF gene expression is highly associated with the vascularity of tumors,which may depend on a hal- ance between MME and VEGF expression.