Structural characterizations andα-glucosidase inhibitory activities of four Lepidium meyenii polysaccharides with different molecular weights

Four polysaccharides(MCPa,MCPb,MCPc,MCPd)were obtained from Lepidium meyenii Walp.Their structures were characterized by chemical and instrumental methods including total sugar,uronic acid and protein content determi-nation,UV,IR and NMR spectroscopy,as well as monosaccharide composition determination and methylation analy-ses.Four polysaccharides were a group of glucans with different molecular weights ranging from 3.12 to 14.4 kDa,and shared a similar backbone chain consisting of(1→4)-glucose linkages with branches attached to C-3 and C-6.Furthermore,bioactivity assay showed that MCPs had concentration-dependent inhibitory activity onα-glucosidase.MCPb(Mw=10.1 kDa)and MCPc(Mw=5.62 kDa)with moderate molecular weights exhibited higher inhibitory activ-ity compared with MCPa and MCPd.

Four undescribed pyrethrins from seeds of Pyrethrum cinerariifolium and their aphidicidal activity

Four undescribed pyrethrins C-F(1-4)as well as four known pyrethrins(5-8)were isolated from seeds of Pyrethrum cinerariifolium Trev.The structures of compounds 1-4 were elucidated by UV,HRESIMS,and NMR(^(1)H and ^(13)C NMR,^(1)H-^(1)H COSY,HSQC,HMBC and ROESY),among which the stereostructure of compound 4 was determined by calcu-lated ECD.Furthermore,compounds 1-4 were evaluated for their aphidicidal activities.The insecticidal assay results showed that 1-4 exhibited moderate aphidicidal activities at the concentration of 0.1 mg/mL with the 24 h mortality rates ranging from 10.58 to 52.98%.Among them,pyrethrin D(2)showed the highest aphidicidal activity,with the 24 h mortality rate of 52.98%,which was slightly lower than the positive control(pyrethrin II,83.52%).

Intraoperative ultrasonography in hepatobiliary surgery

Objective: To assess the value of intraoperative ultra- sonography in hepatobiliary surgery. Methods: Aloka-650 and Aloka-500 with a 3.5 MHz probe were used in preoperative uitrasonography and those with 5 MHz or 7.5 MHz probes in intraopera- tive ultrasonography. All patients with carcinoma were confirmed pathologically. Results: In 44 patients with liver cancer (76 tumors), the diagnostic rate of intraoperative ultra- sonography was 97% (74/76), which was markedly higher than 84% (64/76) of preoperative ultra- sonography (P<0.05). The diagnostic rate (92%; 22/24) of intraoperative ultrasonography for tumors ≤2 cm in diameter was markedly higher than that (54%; 13/24) of preoperative ultrasonography (P< 0.01). The diagnostic rate (94%; 16/17) of intra- operative ultrasonography for tumor embulus of the vein was also markedly higher than that (53%; 9/ 17) of preoperative ultrasonography (P<0.01). The diagnostic rates of intraoperative and preoperative ultrasonography for cholelithiasis were 99% (108/ 109) and 97% (106/109) respectively (P>0.05). Yet the diagnostic rate (100%; 12/12) of intraopera- tive ultrasonography for gallbladder carcinoma was markedly higher than that (66.7%; 8/12) of pre- operative ultrasonography (P<0.05). The diagnos- tic rates of intraoperative ultrasonography for chole- docholith and biliary tract cancer were all 100%, markedly higher than those (83%; 20/24 and 75%; 12/16) of preoperative ultrasonography (P<0.05). Conclusions: Intraoperative ultrasonography can raise the detective rate of the liver occupying lesions comparing with that of preoperative untrasonogra- phy. It is of valuable in selecting operative scheme and locating small lesions.