Sodium-glucose co-transporters are a family of glucose transporter found in the intestinal mucosa of the small intestine (SGLT-2) and the proximal tubule of the nephron (SGLT-1 and SGLT-2). They contribute to renal glucose reabsorption and most of renal glucose (about 90%) is reabsorbed by SGLT-2 located in the proximal renal tubule. Selectively inhibiting activity of SGLT-2 is an innovative therapeutic strategy for treatment of type 2 diabetes by enhancing urinary glucose excretion from the body. Therefore SGLT-2 inhibitors are considered to be potential antidiabetic drugs with an unique mechanism. This review will highlight some recent advances and structure-activity relationships in the discovery and development of SGLT-2 inhibitors including O-glycoside, C-glycoside, C, O-spiro glycoside and non glycosides.

Objective To clone and express the outer surface protein C ( OspC) from a Chinese Borrelia afzelli FP1 strain and to evaluate the immune protectivity of the recombinant OspC protein ( rOspC) . Methods The gene encoding OspC protein of Borrelia afzelli FP1 strain was amplified by polymerase chain reaction (PCR) and then inserted into pET-30a plasmid to construct the recombinant expression plasmid pET-30a-OspC. The transformed E. coli BL21 strains carrying pET-30a-OspC plasmid were induced by IPTG to express OspC protein. The expressed proteins were purified by Ni-IDA resin chromatography and analyzed by SDS-PAGE and Western blot assay. Indirect immunofluorescence assay ( IFA) was performed to detect anti-rOspC protein antibodies in serum samples from rabbits immunized with rOspC protein. In vitro neutral-ization test was performed for evaluation the immune protectivity of rOspC protein. Results The recombi-nant expression plasmid pET-30a-OspC was successfully constructed and highly expressed in E. coli BL21. A strong antigen-antibody reaction between the rOspC protein and polyclonal antibody against Borrelia afzelli FP1 strain was detected by Western blot assay. The titers of IgG in serum samples from rabbits immunized with rOspC protein were significantly elevated. The in vitro neutralization test indicated that 106/ml of Borre-lia afzelli FP1 strains were neutralized by every anti-OspC protein serum sample from the experiment group. Conclusion The rOspC protein showed a strong immune protectivity against Borrelia afzelli, which could be used in the development of polyvalent subunit vaccine against lyme disease.

Objective To predict the potential geographic distribution of Lyme disease in Qinghai by using Maximum Entropy model (MaxEnt).Methods The sero-diagnosis data of Lyme disease in 6 counties (Huzhu,Zeku,Tongde,Datong,Qilian and Xunhua) and the environmental and anthropogenic data including altitude,human footprint,normalized difference vegetation index (NDVI) and temperature in Qinghai province since 1990 were collected.By using the data of Huzhu Zeku and Tongde,the prediction of potential distribution of Lyme disease in Qinghai was conducted with MaxEnt.The prediction results were compared with the human sero-prevalence of Lyme disease in Datong,Qilian and Xunhua counties in Qinghai.Results Three hot spots of Lyme disease were predicted in Qinghai,which were all in the east forest areas.Furthermore,the NDVI showed the most important role in the model prediction,followed by human footprint.Datong,Qilian and Xunhua counties were all in eastern Qinghai.Xunhua was in hot spot area Ⅱ,Datong was close to the north of hot spot area Ⅲ,while Qilian with lowest sero-prevalence of Lyme disease was not in the hot spot areas.The data were well modeled in MaxEnt (Area Under Curve=0.980).Conclusions The actual distribution of Lyme disease in Qinghai was in consistent with the results of the model prediction.MaxEnt could be used in predicting the potential distribution patterns of Lyme disease.The distribution of vegetation and the range and intensity of human activity might be related with Lyme disease distribution.