目的:使用反相高效液相色谱法测定色盐杆菌新种ST307的DNAG+Cmol%含量。方法:以Escherichia coli DH5α为标准菌株,采用90%重蒸水10%甲醇为流动相,检测波长260nm,流速1ml.min-1,在VenusilM P C18柱上对四种碱基进行分离。结果:DNA碱基...目的:使用反相高效液相色谱法测定色盐杆菌新种ST307的DNAG+Cmol%含量。方法:以Escherichia coli DH5α为标准菌株,采用90%重蒸水10%甲醇为流动相,检测波长260nm,流速1ml.min-1,在VenusilM P C18柱上对四种碱基进行分离。结果:DNA碱基分离效果好,以外标法计算得到标准菌株DH5α的DNAG+Cmol%含量为50.3%,待测菌株ST307的DNAG+Cmol%含量为60.5%。结论:采用反向高效液相色谱法测定色盐杆菌的DNAG+Cmol%含量准确可靠。展开更多
AIM: To investigate dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin(DC-SIGN) expression in intestinal epithelial cells(IECs) in inflammatory bowel disease(IBD).METHODS: The expression o...AIM: To investigate dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin(DC-SIGN) expression in intestinal epithelial cells(IECs) in inflammatory bowel disease(IBD).METHODS: The expression of DC-SIGN in IECs was examined by immunohistochemistry of intestinal mucosal biopsies from 32 patients with IBD and 10 controls.Disease activity indices and histopathology scores were used to assess the tissue lesions and pathologic damage.Animal studies utilized BALB/c mice with dextran sodium sulfate(DSS)-induced colitis treated with anti-P-selectin lectin-EGF domain monoclonal antibody(PsL-EGFmA b).Controls,untreated and treated mice were sacrificed after 7 d,followed by isolation of colon tissue and IECs.Colonic expression of DC-SIGN,CD80,CD86 and MHC Ⅱ was examined by immunohistochemistry or flow cytometry.The capacity of mouse enterocytes or dendritic cells to activate T cells was determined by coculture with naive CD4+ T cells.Culture supernatant and intracellular levels of interleukin(IL)-4 and interferon(IFN)-γ were measured by enzyme-linked immunosorbent assay and flow cytometry,respectively.The ability of IECs to promote T cell proliferation was detected by flow cytometry staining with carboxyfluorescein diacetate succinimidyl ester.RESULTS: Compared with controls,DC-SIGN expression was significantly increased in IECs from patients with Crohn's disease(P < 0.01) or ulcerative colitis(P < 0.05).DC-SIGN expression was strongly correlated with disease severity in IBD(r = 0.48; P < 0.05).Similarly,in the DSS-induced colitis mouse model,IECs showed upregulated expression of DC-SIGN,CD80,CD86 and MHC,and DC-SIGN expression was positively correlated with disease activity(r = 0.62: P < 0.01).IECs from mouse colitis stimulated naive T cells to generate IL-4(P < 0.05).Otherwise,dendritic cells promoted a T-helper-1-skewing phenotype by stimulating IFN-γ secretion.However,DC-SIGN expression and T cell differentiation were suppressed following treatment of mice with DSS-induced colitis with Ps L-EGFm Ab.The proliferation cycles of CD4+ T cells from mice with DSS-induced colitis appeared as five cycles,which was more than in the control and treated groups.These results suggest that IECs can promote T cell proliferation.CONCLUSION: IECs regulate tissue-associated immune compartments under the control of DC-SIGN in IBD.展开更多
The corrosion inhibition effect of Capsella bursa-pastoris extracts(CBE) for Q235 carbon steels in 1 mol·L-1hydrochloric acid solution was studied using electrochemical methods, environmental scanning electron mi...The corrosion inhibition effect of Capsella bursa-pastoris extracts(CBE) for Q235 carbon steels in 1 mol·L-1hydrochloric acid solution was studied using electrochemical methods, environmental scanning electron microscopy(SEM) and Raman microscopy analysis. The polarization plots indicate that CBE serves as an effective, mixedtype inhibitor. Linear polarization resistance shows that increasing CBE concentration and temperature results in increased inhibition ef ficiency. The highest inhibition ef ficiency can reach 97% when adding 60 mg·L-1CBE,which is better than some reported plant extracts under the similar environment. The adsorption of CBE molecules is found to obey the Langmuir adsorption isotherm. Some thermodynamic and kinetic parameters for the adsorption process, such as the adsorption equilibrium constant(K), free energy of adsorption(ΔG ads), activation energy of corrosion reaction(E a) and the heat of adsorption(Q ads), are calculated and discussed. SEM and Raman microscopy analysis also demonstrate the formation of a CBE inhibition film on the metal surface.展开更多
文摘目的:使用反相高效液相色谱法测定色盐杆菌新种ST307的DNAG+Cmol%含量。方法:以Escherichia coli DH5α为标准菌株,采用90%重蒸水10%甲醇为流动相,检测波长260nm,流速1ml.min-1,在VenusilM P C18柱上对四种碱基进行分离。结果:DNA碱基分离效果好,以外标法计算得到标准菌株DH5α的DNAG+Cmol%含量为50.3%,待测菌株ST307的DNAG+Cmol%含量为60.5%。结论:采用反向高效液相色谱法测定色盐杆菌的DNAG+Cmol%含量准确可靠。
基金Supported by Grants from the National Natural Science Foundation of China No.81000163,No.81070567,and No.81170363
文摘AIM: To investigate dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin(DC-SIGN) expression in intestinal epithelial cells(IECs) in inflammatory bowel disease(IBD).METHODS: The expression of DC-SIGN in IECs was examined by immunohistochemistry of intestinal mucosal biopsies from 32 patients with IBD and 10 controls.Disease activity indices and histopathology scores were used to assess the tissue lesions and pathologic damage.Animal studies utilized BALB/c mice with dextran sodium sulfate(DSS)-induced colitis treated with anti-P-selectin lectin-EGF domain monoclonal antibody(PsL-EGFmA b).Controls,untreated and treated mice were sacrificed after 7 d,followed by isolation of colon tissue and IECs.Colonic expression of DC-SIGN,CD80,CD86 and MHC Ⅱ was examined by immunohistochemistry or flow cytometry.The capacity of mouse enterocytes or dendritic cells to activate T cells was determined by coculture with naive CD4+ T cells.Culture supernatant and intracellular levels of interleukin(IL)-4 and interferon(IFN)-γ were measured by enzyme-linked immunosorbent assay and flow cytometry,respectively.The ability of IECs to promote T cell proliferation was detected by flow cytometry staining with carboxyfluorescein diacetate succinimidyl ester.RESULTS: Compared with controls,DC-SIGN expression was significantly increased in IECs from patients with Crohn's disease(P < 0.01) or ulcerative colitis(P < 0.05).DC-SIGN expression was strongly correlated with disease severity in IBD(r = 0.48; P < 0.05).Similarly,in the DSS-induced colitis mouse model,IECs showed upregulated expression of DC-SIGN,CD80,CD86 and MHC,and DC-SIGN expression was positively correlated with disease activity(r = 0.62: P < 0.01).IECs from mouse colitis stimulated naive T cells to generate IL-4(P < 0.05).Otherwise,dendritic cells promoted a T-helper-1-skewing phenotype by stimulating IFN-γ secretion.However,DC-SIGN expression and T cell differentiation were suppressed following treatment of mice with DSS-induced colitis with Ps L-EGFm Ab.The proliferation cycles of CD4+ T cells from mice with DSS-induced colitis appeared as five cycles,which was more than in the control and treated groups.These results suggest that IECs can promote T cell proliferation.CONCLUSION: IECs regulate tissue-associated immune compartments under the control of DC-SIGN in IBD.
基金Supported by the National Natural Science Foundation of China(51101066)
文摘The corrosion inhibition effect of Capsella bursa-pastoris extracts(CBE) for Q235 carbon steels in 1 mol·L-1hydrochloric acid solution was studied using electrochemical methods, environmental scanning electron microscopy(SEM) and Raman microscopy analysis. The polarization plots indicate that CBE serves as an effective, mixedtype inhibitor. Linear polarization resistance shows that increasing CBE concentration and temperature results in increased inhibition ef ficiency. The highest inhibition ef ficiency can reach 97% when adding 60 mg·L-1CBE,which is better than some reported plant extracts under the similar environment. The adsorption of CBE molecules is found to obey the Langmuir adsorption isotherm. Some thermodynamic and kinetic parameters for the adsorption process, such as the adsorption equilibrium constant(K), free energy of adsorption(ΔG ads), activation energy of corrosion reaction(E a) and the heat of adsorption(Q ads), are calculated and discussed. SEM and Raman microscopy analysis also demonstrate the formation of a CBE inhibition film on the metal surface.
