Nuclepore polycarbonate membrane filtration was applied for the purification of tacky-zoites in the peritoneal exudate and the saline peritoneal washing from infected mice with Toxoplasma gondii RH strain or Beverley strain. The recovery rate of tackyzoites by this method was 65. 8% and the purity of the protozoa in the filtrated suspension was as high as 98. 87%, while the protozoa in 98. 4% of the host leucocytes and 85. 2% of host erythrocytes were elimina ted respectively. The ratio of host cells to the protozoa in filtrated suspension was both lower than 1 : 100. Stain of tackyzoites with fluorescent dyes showed that more than 99% of the protozoa were alive after filtration and the re-infection of mice with the purified tackyzoites suggested that the viability, toxicity and infectivity of the tackyzoites were not affected apparently. This method was shown to be a harmless, highly efficiency, time-saving, simple, and ease method for the purification of T. gondii tackyzoites.

Objective To investigate the effect of sterol regulating element binding protein (SREBP1c) and its ac-tive form (SREBP1cm) on human protein kinase R-like endoplasmic reticulum kinase (PERK).Methods Re-porter victors of PERK promoter and its truncations were constructed with pGL 3-basic and co-transfected with internal reference pRL-SV40 into cell and luciferase activity was detected .pcDNA3.1 ( -)-SREBP1c or pcDNA3.1 ( -)-SREBP1cm was co-transfected with PERK promoter transcriptional activity core regions and the detection of dual -lu-ciferase reporter gene was used to analyze the regulation of SREBP 1c/1cm on PERK promoter transcriptional activity . The expression level of PERK mRNA and protein were detected by RT-PCR and Western blot .Results PERK pro-moter and truncations were successfully constructed into pGL 3-basic, and PERK promoter core area of transcription-al activity had determined;Dual-luciferase report gene showed that SREBP 1c inhibited PERK promoter transcrip-tional activity and SREBP1cm promoted PERK promoter transcriptional activity .RT-PCR and Western blot showed that SREBP1c decreased PERK mRNA and protein expression , but SREBP1cm increased PERK mRNA and protein expression, which was consistent with the detection of dual-luciferase report gene .Conclusions SREBP1c and SREBP1cm have a opposite regulation effect on PERK promoter transcriptional activity and its expression .

Objective To assess the longitudinal mitral annular plane systolic excursion ( M APSE) of different directions in normal fetuses during mid‐late pregnancy based on two‐dimensional speckle tracking imaging ( ST I) . Methods Seventy‐six normal fetuses during middle and late pregnancy were selected at 26－32 weeks of gestation . T he peak M APSE was measured by free angle M‐mode echocardiography ( FAM ) perpendicular to the lateral annulus in the mitral annular plane . The time‐displacement curves of interventricular septal mitral annulus in three different directions including points A ,B and C through transverse level of apex were recorded by STI . T he peak M APSE of interventricular septal mitral annulus ( SEPT‐M APSE‐A ,SEPT‐M APSE‐B ,SEPT‐M APSE‐C) in three different directions including points A ,B and C and the time to peak ( T T P :SEPT‐T T P‐A ,SEPT‐T T P‐B ,SEPT‐T T P‐C) were recorded respectively . T he time‐displacement curves of lateral mitral annulus in three different directions including points A ,B and C through transverse level of apex were recorded by STI . T he peak M APSE of lateral mitral annulus ( LAT‐M APSE‐A ,LAT‐MAPSE‐B ,LAT‐MAPSE‐C) in three different directions including points A ,B and C ,the time to peak( LA T‐T T P‐A ,LA T‐T T P‐B ,LA T‐T T P‐C) were recorded respectively . Finally ,the data were analyzed statistically . Results T he peak M APSE of the lateral mitral annulus in 3 different directions including points A ,B and C[ LA T‐M APSE‐A ( 3 .62 ± 1 .01) mm ,LA T‐M APSE‐B ( 3 .95 ± 1 .04) mm ,LAT‐M APSE‐C ( 4 .45 ± 1 .05) mm ] were greater than those of the interventricular septum mitral annulus[ SEPT‐MAPSE‐A (3 .41 ± 0 .63)mm ,SEPT‐MAPSE‐B (3 .07 ± 0 .50) mm ,SEPT‐MAPSE‐C (2 .82 ± 0 .51) mm] . LAT‐M APSE‐C and SEPT‐M APSE‐A were the largest longitudinal excursions of mitral annulus . T he differences were statistically significant in points B and C ( P ＜0 .05) . T here was no significant difference in point A ( P ＞0 .05) . LA T‐M APSE‐C was less than FAM‐M APSE [ ( 6 .06 ± 1 .35 ) mm ] . T here was a significant difference between them ( P ＜0 .05 ) . Strong correlation was found between them ( r ＝0 .896 , P＜0 .05) . T here were no significant differences in the time to peak of interventricular septal mitral annulus [ SEPT‐T T P‐A ( 0 .210 ± 0 .008 ) s ,SEPT‐T T P‐B ( 0 .213 ± 0 .008 ) s ,SEPT‐T T P‐C ( 0 .210 ± 0 .005 ) s] in directions including points A ,B ,C ( P＞ 0 .05 ) . T here were no significant differences in time to peak of lateral mitral annulus [ LAT‐T T P‐A ( 0 .210 ± 0 .008 ) s , LAT‐T T P‐B ( 0 .213 ± 0 .006 ) s , LAT‐T T P‐C ( 0 .210 ± 0 .007) s] in directions inclucling points A ,B ,C ( P ＞0 .05) . Conclusions Longitudinal systolic motion of fetal left ventricular wall during mid‐late pregnancy has good synchronization . Longitudinal motion of fetal mitral annulus is a comprehensive movement of multiple directions and different degrees of displacement ,with the movement perpendicular to the annulus as the maximum displacement direction . T he displacement parameters of mitral annulus measured by ST I can reflect the left ventricular longitudinal systolic function and have clinical application value in evaluating the left ventricular longitudinal systolic function of fetuses .

Objective: To assess the longitudinal mitral annular plane systolic excursion (MAPSE) of different directions in normal fetuses during mid-late pregnancy based on two-dimensional speckle tracking imaging (STI). Methods: Seventy-six normal fetuses during middle and late pregnancy were selected at 26-32 weeks of gestation. The peak MAPSE was measured by free angle M-mode echocardiography (FAM) perpendicular to the lateral annulus in the mitral annular plane. The time-displacement curves of interventricular septal mitral annulus in three different directions including points A, B and C through transverse level of apex were recorded by STI. The peak MAPSE of interventricular septal mitral annulus (SEPT-MAPSE-A, SEPT-MAPSE-B, SEPT-MAPSE-C) in three different directions including points A, B and C and the time to peak (TTP: SEPT-TTP-A, SEPT-TTP-B, SEPT-TTP-C) were recorded respectively. The time-displacement curves of lateral mitral annulus in three different directions including points A, B and C through transverse level of apex were recorded by STI. The peak MAPSE of lateral mitral annulus (LAT-MAPSE-A, LAT-MAPSE-B, LAT-MAPSE-C) in three different directions including points A, B and C, the time to peak(LAT-TTP-A, LAT-TTP-B, LAT-TTP-C) were recorded respectively. Finally, the data were analyzed statistically. Results: The peak MAPSE of the lateral mitral annulus in 3 different directions including points A, B and C[LAT-MAPSE-A (3.62±1.01)mm, LAT-MAPSE-B (3.95±1.04)mm, LAT-MAPSE-C (4.45±1.05)mm] were greater than those of the interventricular septum mitral annulus[SEPT-MAPSE-A (3.41±0.63)mm, SEPT-MAPSE-B (3.07±0.50)mm, SEPT-MAPSE-C (2.82±0.51)mm]. LAT-MAPSE-C and SEPT-MAPSE-A were the largest longitudinal excursions of mitral annulus. The differences were statistically significant in points B and C (P<0.05). There was no significant difference in point A (P>0.05). LAT-MAPSE-C was less than FAM-MAPSE[(6.06±1.35)mm]. There was a significant difference between them(P<0.05). Strong correlation was found between them(r=0.896, P<0.05). There were no significant differences in the time to peak of interventricular septal mitral annulus [SEPT-TTP-A (0.210±0.008)s, SEPT-TTP-B (0.213±0.008)s, SEPT-TTP-C (0.210±0.005)s] in directions including points A, B, C(P>0.05). There were no significant differences in time to peak of lateral mitral annulus[LAT-TTP-A(0.210±0.008)s, LAT-TTP-B(0.213±0.006)s, LAT-TTP-C(0.210±0.007)s] in directions inclucling points A, B, C(P>0.05). Conclusions Longitudinal systolic motion of fetal left ventricular wall during mid-late pregnancy has good synchronization. Longitudinal motion of fetal mitral annulus is a comprehensive movement of multiple directions and different degrees of displacement, with the movement perpendicular to the annulus as the maximum displacement direction. The displacement parameters of mitral annulus measured by STI can reflect the left ventricular longitudinal systolic function and have clinical application value in evaluating the left ventricular longitudinal systolic function of fetuses.