As one of the most sensitive cells of endoplasmic reticulum stress,pancreatic βcells have an abundance of endoplasmic reticulum .It is the adaptive response of pancreatic β cells under Endoplasmic reticulum stress conditions.Internal and external factors in the environment such as oxidative damage,lipid toxicity and the effect of cytokines in the endoplasmic reticulum could breake the steady-state,resulting in barriers to folding or misfolding of protein,thereby to trigger endoplasmic reticulum stress.Serious and lasting stress will lead to β cell apoptosis,involved in a variety of metabohc diseases as well as a variety of diseases.This article gives a review on the injury effects of multi-factor induced endoplasmic reticulum stress on the pancreatic β-cell

Objective To study the immunogenicity of Streptococcus pneumoniae pneumolysin DNA vaccine in Rhesus macaques. Methods The deletion of the gene sequence encoding for the 11 amino acids at the carboxyl terminal of pneumolysin (PN) from its wild type gene (pn) by PCR resulted in a mu-tant pneumolysin gene (pnd). The wild type pn gene encoding PN and the mutant gene (pnd) encoding PND were cloned into pVAX1 vector respectively and then tested as Ppn and Ppnd DNA vaccines. The PN and PND proteins were purified from recombinant E. coli. Rhesus macaques were immunized by intramuscu-larly (i.m.) injection of Ppn or Ppnd DNA vaccine with electroporation (EP). Results Because of the deletion of the gene sequence encoding for the eleven amino acids at the carboxyl terminal of the PN from pn gene, the recombinant PND antigen lost its hemolytic activity while its antigenicity was remained. The spe-cific humoral immunity against pneumolysin was induced by injecting monkey with 500 μg DNA followed by EP. Boosting the Ppn or Ppnd DNA/EP primed animals with corresponding recombinant protein, PN or PND, evoked strong immune response at about 4 fold increase in the antibody titer. Conclusion Specific antibody responses were induced in the monkeys by DNA vaccination and electroporation. The immunogenic-ity of the DNA vaccines were significantly enhanced when PN or PND protein boost was applied 10 d after third DNA vaccination.

To investigate the mechanism of electroacupuncturein treating chronic fatigue syndrome(CFS) in term of the neuro-endocrine system by observing the regulative effect of EA on hypothalamic-pituitary-adrenal index (HPA index) and corticotropin releasing hormone mRNA (CRH mRNA) in CFS model rats. Methods: The rats were randomly divided into control group, model group, and electroacupuncture group. Model and electroacupuncture groups were forced to swim in cold water to make CFS model, while rats in electroacupuncture group were treated with electroacupuncture treatment at the same time. Electroacupuncture group was given at Baihui(GV 20) and Zusanli(ST 36). Evaluation of the model was processed according to the behavior changes of the rats. Hypothalamic, pituitary, and adrenal were weighted to calculate HPA index. CRH mRNA in hypothalamic was measured by fluorescence quantitative polymerase chain reaction (FQPCR). Results: The model rats had behavior changes,and both physical and mental fatigue was observed. HPA index raised and expression of CRH mRNA in hypothalamus increased in CFS rats. After electroacupuncture treatment, the physical and mental fatigue was improved, and the hypothalamic index and CRH mRNA decreased significantly, while the pituitary and adrenal index only had little decrease. Conclusion: Cold water swim press could mimic the pathogenesis and make similar manifestations in rats with the common clinical symptoms. CFS has close relationship with increase of HPA index and CRH mRNA expression. Electroacupuncture can regulate the function of HPA axis to deal with CFS.

Objective To prepare the chitosan-potD nanoparticles and to evaluate its protective efficacy against pneumococcal nasopharyngeal colonization. Methods potD gene was amplificated from pneumococcal genome and was inserted into pVAX1 expression vectors to construct pVAX1-potD recombinant plasmid which was then transfected into 293T cell using LipofectAMINE 2000 to analyze transient potD gene expression in vitro by RT-PCR and Western blot. Chitosan-potD nanoparticles were freshly prepared by coacervation methods at each time and the characterizations of the nanoparticles were then evaluated. BALB/c mice were immunized with chitosan-potD, naked potD DNA or pVAX1 for 4 times at two-week intervals. Anti-PotD IgG, IgG1 and IgG2a levels in serum and IgA levels in nasal washes, bronchoalveolar lavage fluids (BALF) and middle ear lavages(MEL) were detected by indirect enzyme-linked immunosorbent assay (ELISA). IL-17A, IL-4 and IFN-γ levels in splenocytes were determined by double sandwich ELISA. Mice were intrannsally challenged with Streptococcus pneumoniae ATCC6303, and Pneumococci were recovered from the nasopharyngeal niche at the fifth day after challenge. Results potD gene was successfully amplificated by PCR and the sequence was confimed to be consistent with that in the Genbank. The pVAX1-potD recombinant plasmid was successfully constructed and was expressed in eukaryocytes in vitro. The mean size and zeta potential of chitosan-potD nanoparticles was 430 nm and + 20.5 mv, respectively. Chitosan-potD nanoparticles were not digested by DNase Ⅰ , while naked potD DNA was completely digested. The levels of antibodies inculding IgG, IgG1, IgG2a, IgA and cytokines including IL-17A, IL-4 and IFN-γ were significantly higher in mice immunized with chitosan-potD nanoparticles than mice with naked potD or pVAX1 ( P <0.05) only. More importantly, much less Pneumococci were recovered from mice immunized with chitosan-potD nanoparticles than the other groups(P <0.05). Conclusion Chitosan-potD nanoparticles significantly enhanced the immunogenicity and protection efficacy of DNA vaccines by intranasal immunization and could be used as a potential mucosal vaccine to prevent pneumococcal infection.

Objective To evaluate in vitro anti tumor effect of host lymphocyte primed by CalmetteGuerin bacillus (CGB) activated dendritic cells (DC) based PANC1 lysate. Methods DCs were obtained from peripheral blood mononuclear cells of healthy volunteer and cuitured by rhGM CSF and rhIL 4. DC vaccines for pancreatic cancer were loaded with PANC1 tumor lysate (TL) and were further maturated by CGB.CD1a, CD83, CD86 and HLA-DR phenotype was characterized by flow cytometer, and IL-12p70 and TNF-α concentration in DC culture supernatant were measured by ELISA. Autologous mixed lymphocyte proliferation and the cytotoxicity of cytotoxic T lymphocytes primed by activated DCs to PANC1, PaTu8988 and SCG7901 tumor cells was measured by CCK 8 test. Results When DCs based PANC1 lysate were activated by CGB,the expression rates of CD83 and CD86 were increased from (3.7±0.3)% and (38.6±5.0)% to (16.5±0.6)% and (76.6±2.5)% (P ＜0.05 ). The concentrations of cytokines ILpl2p70 and TNF-α were increased from (20.18±2.06 ) pg/mland (61.38±1.19) pg/mlto (62.48±3.80) pg/mland (592.53±17.96)pg/ml (P＜0. 01 ). When co-cultured with CGB activated DCs based PANC1 lysate in proportion of 0.40)% , (3.39±1.05)% , (2.82±0.39)% significantly increased to (55.38±3.58)% , (75.0±2.54) % , (77.07±3.4)% , (99.07±2.4)% (P＜0.01) , respectively. The killing effects of lymphocytes 2.77)%, (19.03±3.04) %; but the killing effects on PaTu8988 and SCG7901 were significantly decreased.Conclusions DC vaccines for pancreatic cancer could be more maturated when activated by CGB, and could show a high capability of anti-tumor in vitro.

Aim To investigate the effect of ginkgolide B on TLR4 expression in glucose-treated endothelial cells.Methods Human umbilical vein endothelial cells (HUVECs)were stimulated by high concentra-tion of glucose.TLR4,inflammatory protein expression and Akt phosphorylation were analyzed by Western blot.Transcription factor NF-κB nuclear translocation was analyzed by immunofluorescence.Results The expression of TLR4 and PAF receptor was increased in high glucose-treated HUVECs. In contrast, both ginkgolide B and CV3988 dose-dependently decreased TLR4 and PAF receptor expression in high glucose-treated cells,respectively.Ginkgolide B decreased in-flammatory protein ICAM-1 ,VCAM-1 expression.Mo-reover,ginkgolide B potently abolished Akt phospho-rylation and NF-κB p65 nuclear translocation.Conclu-sion Ginkgolide B can reduce TLR4,PAF receptor, ICAM-1 and VCAM-1 expression in high dose of glu-cose-treated HUVECs,the mechanism might be linked to inhibition of Akt phosphorylation and NF-κB activa-tion.

OBJECTIVE To prepare pneumolysin(Pn)by genetic engineering and thereby establish the basis for the study of vaccines against otitis media. METHODS A pair of primers including two restriction sites was designed based on the pneumolysin gene sequence reported by Walker in 1987. The pneumolysin gene was PCR-amplified from pneumococcal DNA. The resulting fragment, digested by restriction enzymes, was ligated into the vector PET-28a and then transformed into host cell E.coli JM109(DE3). RESULTS The sequence of the inserted pneumolysin gene was confirmed by DNA sequencing. CONCLUSION The pneumolysin gene was successfully cloned into the host cell.

Obiective To investigate the molecular characteristics of heteroresistant vancomycinintermediate Staphylococcus aureus(hVISA)in China and analyze the differences of the molecular characteristics between hVISA and VSSA(vancomycin-susceptible Staphylococcus aureus)isolates.Methods A total of 3 15 non-repetitive MBSA were collected from the national surveillance program in China in 2007.The isolates of hVISA were confirmed by modified population analysis profile-area under the curve(PAP-AUC).The genotypes of agr and SCCmec were determined by multiplex PCR,and spa typing was performed bv PCR and DNA sequencing.The pvl gene was detected bv PCR Results The prevalence of hVISA was 9.5%(30/315).Among 315 MRSA,SCCmec Ⅲ was the most popular type,which was found in 234 isolates(234/315,74.3%),followed by SCCmec Ⅱ,which was identified in 56 isolates (56/315,17.8%).The rate of SCCmec Ⅱ in hVISA(46.7%)was significantly hisher than in VSSA (14.7%,X~2=18.93,P＜0.001).The most prevalent agr type among 315 MRSA was agr 1 accounting for 73.6%(232/315).The agr 2 accounted for 18.7%(59/315),and agr 3 and agr 4 were very rare in clinical isolates.It was different in agr types between the two groups.The rate of agr 2 in hVISA(53.4%)was higher than in VSSA(15.1%).X~2 value was 26.08 and P value was less than 0.001 through X~2 test.There was a statistical significance in the result.There were 4 spa types in hVISA isolates,including t002 (13 isolates),t037(9 isolates),t030(6 isolates),and 1548(2 isolates).The pvl positive MRSA isolates were very low,accounting for 1.6%(5/315).Conclusions The prevalence of hVISA was relatively higher in China.Compared to VSSA,the majority(53.4%)of the hVISA strains were agr 2,which was obviously different from VSSA.hVISA isolates were more diverse by spa typing,

Objective To evaluate the clinical efficacy and safety of endoscopic mucosal resection (EMR) assisted with magnifying chromoendoscopy in treatment of colorectal neoplasms. Methods Patients who met criteria for EMR including appropriate flat or depressed type and sessile lesions were enrolled. The association of morphology of colorectal lesions with histopathology was observed and the accuracy of estimation of invasive depth by magnifying chromoendoscopy was evaluated. Results Ninety lesions of 81 patients were reseeted by EMR (25 being sessile and 65 being flat or depressed). The histological results revealed low-grade dysplasia (LGD) in 58 lesions, high-grade dysplasia (HGD) in 20 lesions, and adenocarcinoma in 12 lesions. The average size of lesions was (1.4±0.5) cm in HGD, (1.6±0.5) cm in cancer and (1.0±0.4) cm in LGD with no significant difference (P> 0.05). It was shown that the flat and depressed lesions were more likely to be HGD or cancer as compared to sessile lesions, but with no statistical difference [41.5 % (27/65)vs. 20.0% (5/25), P= 0.084]. Moreover, the lesion with central depression was more likely to be HGD or cancer as compared to those without depressed surface [51.0% (25/49) vs. 17.1 % (7/41), P<0.01)]. The accuracy of estimating invasive depth by magnifying chromoendoscopy was 97.8% (86/90). Complete resection was confirmed histologically in 95.8% (88/90) of all lesions. Conclusions Colorectal lesions of depressed and flat types with central depression are more likely to be malignant. Estimation of invasive depth of colorectal neoplasia by magnifying chromoendoscopy in EMR treatment makes it more effective and safer.

BACKGROUND: Exosomes are nano-scale vesicles that can be secreted by almost all types of cells in the body, which can participate in multiple cell signaling pathways by transporting signal molecules, such as proteins, lipids and miRNAs to perform intercellular communication, immune responses, and antigen presentation. Therefore, exosomes have a great value in the clinical diagnosis and treatment of diseases. Of the cell types known to produce exosomes, mesenchymal stem cells are currently the most prolific producer closely related to the occurrence and development of neurodegenerative diseases. OBJECTIVE: To review the origin and biological characteristics of mesenchymal stem cell-derived exosomes, the isolation and identification methods of exosomes, and the progress of mesenchymal stem cell-derived exosomes in the treatment of neurodegenerative diseases. METHODS: The literature search was performed in PubMed and CNKI databases, and the keywords were "mesenchymal stem cells; exosomes; MSC-exosomes; neurodegenerative diseases" in Chinese and English, respectively. RESULTS AND CONCLUSION: A total of 61 eligible literatures were enrolled. Mesenchymal stem cell-derived exosomes have low immunogenicity and long-circulating half-life and can carry small molecular substances across the blood-brain barrier, which can promote nerve cell growth and neuronal differentiation. Mesenchymal stem cell-derived exosomes help damaged nervous system function and enhance vascular neurogenesis, which is becoming an emerging treatment for neurodegenerative diseases.