Exploration and practice of process assessment in Human Parasitology teaching for international medical students / 中国血吸虫病防治杂志

Teaching evaluation is an important measure to test the teaching quality. In order to better achieve the training objectives among international medical students based on the specific conditions of foreign students and the characteristics of Human Parasitology, a process-based assessment and evaluation system has been established for international medical students. The process assessment highlights the characteristics of assessment process, diversified forms and inquires of test questions. Following implementation of process assessment, the proportion of excellence (examination scores of 90 and higher) improved from 3.25% (10/308) to 13.09% (50/382) (t = 5.995, P < 0.001) and the proportion of good marks (examination scores of 80 to 89) increased from 18.83% (58/308) to 36.13% (138/382) (t = 7.505, P < 0.001) during the semester assessment among international medical students at five grades, while the proportion of failure in examination pass (examination scores of below 60) reduced from 12.34% (38/308) to 3.24% (10/382) (t = 7.303, P < 0.000 1), indicating that the process-based assessment and evaluation system improves the examination score of Human Parasitology among international medical students and the teaching quality of Human Parasitology.

Effect of inducible costmulator/inducible costmulator ligand signaling pathway on hepatic fibrosis in mice infected with Schistosoma japonicum / 中华传染病杂志

Objective To analyze the effect of inducible costmulator (ICOS)/inducible costmulator ligand (ICOSL) signaling pathway on hepatic fibrosis in mice infected with Schistosoma japonicum.Methods Seventy-eight ICOSL knockout (ICOSL-KO) mice and 77 wild type C57BL/6J mice were used as experimental schistosomiasis model infected with Schistosoma japonicum.The sera of mice were collected on the day before infection (0 week),and at 4,7,12,16 and 20 weeks post infection.Then,the concentrations of hyaluronic acid (HA) and hydroxyproline (HYP) in mice sera were measured by sandwich enzyme linked immunosorbent assay (ELISA) kits.The expressions of transforming growth factor β1 (TGF-β1),α-smooth muscle actin (a-SMA) and Collagen-Ⅰ in livers from ICOSL-KO/wild type mice were assessed by immunohistochemical staining.The granulomatous pathology and fibrosis level in mice liver were dynamically observed by hematoxylin and eosin (HE) staining and Masson's staining,respectively.The difference between groups was detected by t test or x2 test when appropriate.Results After infection with Schistosoma japonicum,the levels of HA and HYP were gradually increased.In ICOSL-KO mice,the levels of HA at 7,12,16 and 20 weeks post infection were all significantly lower than those in wild type mice [(161.32±15.44) vs (186.01±21.24) ng/mL,t=2.528 2,P＜0.05; (166.73±18.18) vs (231.39±20.12) ng/mL,t=4.342 4,P＜0.05; (193.58±21.06) vs (252.51±25.29) ng/mL,t=4.003 9,P＜0.05; (253.98±24.53) vs (310.88±23.86) ng/mL,t=3.718 0,P＜0.05].Similarly,HYP levels in ICOSL-KO mice at 12,16 and 20 weeks post infection were all significantly lower than those in wild type mice (all P＜0.05).Immunohistochemical staining showed that TGF-β1,α-SMA and Collagen-Ⅰ expressions in liver of ICOSL-KO mice from 7 to 20 weeks post infection were all significantly lower than those of wild type mice (all P＜0.05).HE staining showed,the volume of liver egg granulomas of ICOSL-KO mice was significantly smaller than that of wild type C57BL/6J mice (P＜0.01).Furthermore,Masson's staining showed that the level of hepatic fibrosis in ICOSL-KO mice was lower than that in wild type mice and the fibrosis scores were statistically different between two groups (all P＜0.05).The mortality rate of the wilde type C57BL/6J mice was higher than that of ICOSL-KO mice.After 20 weeks of infection,the difference was statistically significant (55.84 ％ vs 37.18 ％,x2 =5.427,P＜0.05).Conclusions The degree of hepatic fibrosis and related indicators are obviously down-regulated in ICOSL-KO mice infected with Schistosoma japonicum.These findings suggest that ICOS/ICOSL signaling pathway has an important impact on the process of hepatic fibrosis caused by Schistosoma japonicum.

Dynamic alteration of CD154/CD40 and its effects on Th1/Th2 polarization in indu-cible co-stimulator ligand knockout mice infected with Schistosoma japonicum / 北京大学学报(医学版)

Objective:To analyze effect on the CD154-CD40 signaling pathway and Th1/Th2 polariza-tion by deficient inducible co-stimulator ( ICOS)-ICOS ligand ( ICOSL) signaling in mice infected with Schistosoma japonicum. Methods:ICOSL knockout ( ICOSL-KO) mice and wild-type C57BL/6J mice were used as experimental Schistosomiasis model infected with Schistosoma japonicum. The expressions of CD154 and CD40 on splenocytes and on inflammatory cells around granulomatous infiltration of liver in mice infected with Schistosoma japonicum were analyzed by flow cytometry,immunohistochemical staining, respectively, on the day before infection (0 week) and at the end of 4, 7, 12, 16 and 20 weeks post-infection. The splenocytes of the mice were stimulated with soluble egg antigen( SEA) for 72 hours, then the concentrations of interferon gamma(IFN-γ) and interleukin-4 (IL-4) in the culture supernatants were measured by sandwich enzyme-linked immunosorbent assay ( ELISA) kits. The levels of SEA-specific an-tibodies of IgG and IgG1 and IgG2a were measured in the mice sera by ELISA. The granulomatous pa-thology in the mice liver was dynamically observed by hematoxylin and eosin ( HE ) staining. Results:Compared with the wild-type C57BL/6J mice, the expressions of CD154 on CD4 + T splenocytes [(18. 62 ± 4. 76)% vs. (27. 91 ± 3. 94)%, (22. 44 ± 4. 67)% vs. (40. 86 ± 5. 21)%, (25. 50 ± 6. 81)% vs. (43. 81 ± 8. 41)%, (20. 22 ± 5. 28)% vs. (40. 95 ± 7. 34)%, (17. 87 ± 4. 59)% vs. (33. 16 ± 6. 31)%, all P <0. 01] and of CD40 on CD19 + B splenocytes [(19. 43 ± 3. 26)% vs. (24.37 ±3.59)%, (23. 00 ± 4. 47)% vs. (31. 80 ± 5. 86)%, (24. 46 ± 5. 01)% vs. (35. 85 ± 5. 32)%, (23. 42 ± 4. 69)% vs. (33. 30 ± 6. 14)%, (22. 85 ± 3. 78)% vs. (30. 88 ± 5. 94)%, all P<0 . 05 ] in the ICOSL-KO mice significantly decreased at the end of 4 , 7 , 12 , 16 and 20 weeks post-infection. Moreover, the expressions of CD154[(0. 319 ± 0. 066) vs. (0. 488 ± 0. 086), (0. 389 ± 0. 067) vs.(0.596±0.082),(0.378±0.064) vs.(0.543±0.072),(0.348±0.069) vs.(0.523±0.076), all P<0. 01] and CD40[ (0. 398 ± 0. 066) vs. (0. 546 ± 0. 079), (0. 461 ± 0. 085) vs. (0. 618 ± 0. 076), (0. 453 ± 0. 087) vs. (0. 587 ± 0. 074), (0. 449 ± 0. 065) vs. (0. 565 ± 0. 082), all P <0 . 05 ] on inflammatory cells around granulomatous infiltration in liver from the ICOSL-KO mice were sig-nificantly lower than those of the wild-type C57 BL/6 J mice at the end of 7 , 12 , 16 and 20 weeks post-in-fection. The levels of IFN-γ of the ICOSL-KO mice were significantly higher than those of the wild-type C57BL/6J mice at the end of 4, 7, 12, 16 and 20 weeks post-infection (P <0. 05). However, the levels of IL-4 of the ICOSL-KO mice were significantly lower than those of the wild-type mice ( P <0. 05). Compared with the wild-type C57BL/6J mice, the levels of SEA-specific antibodies of IgG and IgG1 and IgG2a in the sera of the ICOSL-KO mice significantly decreased (P<0. 01). Moreover, The Th2 differentiation index of the ICOSL-KO mice was significantly lower than that of the wild-type mice in post-infection (P<0. 01). Also, the ratio of IgG1/IgG2a of the ICOSL-KO mice were significantly lower than that of the wild-type mice at the end of 7 , 12 and 16 weeks post-infection ( P<0 . 05 ) . And the vo-lume of liver egg granulomas of the ICOSL-KO mice was significantly smaller than that of the wild-type mice ( P <0 . 01 ) . Conclusion: These findings suggest that there is obvious down-regulation in the expressions of CD154 and CD40 and impairment of Th2 immune response in the ICOSL-KO mice infected with Schistosoma japonicum, accompanying with notedly reduced hepatic granulomatous pathology. The ICOS-ICOSL signaling has a regulatory effect on CD154-CD40 signaling pathway, and may play an impor-tant role in the hepatic egg granuloma formation of Schistosomiasis.

Drug resistance induction and analysis of differential expression protein on adult Schistosoma j aponicum induced by ED50 PZQ / 中国人兽共患病学报

ABSTRACT:In the present study ,we aimed to identify differentially expressed proteins between induced worms (the infec‐ted mice were treated intragastrically with ED50 PZQ) and uninduced worms (control group) for clarifying the mechanism of PZQ .ED50 PZQ was used to administrate mice that were infected with S .japonicum via intragastric incubation for consecutive‐ly 30 days .Twenty‐one days later ,mice were sacrificed after treatment with 200 mg/kg PZQ for continuously five days ,and the male worms were obtained and some of them were subjected in DMEM medium with different concentrations of PZQ in vitro for 16 hours .Then the worms were washed twice and incubated in PZQ‐free medium for 72 hours .Compared with control group ,the induced worms had lesser sensitivity to PZQ .The survival rate of induced worms was 75 .6% in vitro when the con‐centration of PZQ was 112 mol/L (the concentration was 8 times of uninduced worms Lethal Concentration ) ,significantly higher than that in the uninduced worms (11 .1% ,P<0 .05) ,showing obviously tolerance .The other induced and uninduced worms were acquired and collected for 2D‐DIGE and MALDI‐TOF‐MS ,and combined with bioinformatics to analyse the func‐tion of the identified protein .Thirty differential expression proteins were confirmed between induced and uninduced worms ,in‐cluding 12 proteins up‐regulated and 18 proteins down‐regulated .These proteins respectively ascribed to cytoskeleton‐associat‐ed protein ,glucose and energy metabolism enzymes ,stress proteins ,thioredoxin peroxidase enzymes ,and other protease .Up‐or down‐regulation of these differential proteins indicated that PZQ promote or inhibit the expression of some specific genes . These findings may help to clarify the mechanism of PZQ ,simultaneously ,providing a scientific basis for exploring new vaccine candidate antigens and targets for drug therapy .

The influence of PEG-IFN-α 2a on the expression of ICOS on CD4+ T cell in patients with chronic hepatitis B / 中华微生物学和免疫学杂志

Objective To study the expression levels of inducible costimulator (ICOS) on CD4+ T cells in peripheral blood in patients with chronic hepatitis B and its change after treated with interferon.Methods All 56 patients were divided into two groups (interferon group has 28 cases,lamivudine group has 28 cases),and interferon group treated by PEG-IFN-α 2a,lamivudine group treated by lamivudine,respectively.There were 20 healthy individuals as control group.The levels of ICOS on CD4+ T cells of patients with chronic hepatitis B were kinetically detected by flow cytometry.The copies of HBV DNA in sera were dynamically detected by real-time PCR.Results The levels of ICOS on CD4+ T cells in patients with chronic hepatitis B was higher than that of normal controls(P＜0.001 ).However,the expressions of ICOS on CD4+ T cells in patients could be deduced by PEG-IFN-α 2a and obviously decreased after treatment.There was significant difference between interferon group and lamivudine group (P＜0.05 in 24 weeks,and P＜0.01 in 48 weeks).After treatment,the change values of ICOS in interferon group was positively correlated with the change copies of HBV DNA (r =0.972,P＜0.001 ).However,the change values mentioned above that did not find correlation in lamivudine group(r=-0.101,P=0.608).Conclusion The study shows the patients with chronic hepatitis B have disordered in cellular immunity and increased with the expression of ICOS on CD4+ T cells.PEG-IFN-α 2a could decrease the expression of ICOS on CD4+ T cells in patients,and correct the Th2 type immune polarization to some extent,and that plays a positive role in antiHBV.

Immune response and immunopathology in ICOSL knockout mice infected with Schistosoma japonicum / 中国人兽共患病学报

To determine immune responses and immunopathology in ICOSL knockout (ICOSL KO) mice infected with Schistosoma japonicum,ICOSL- KO mice and wild-type C57BL/6J mice were used as experimental models for Schistosoma japonicum infection.The splenic lymphocytes were isolated from the mice the day before infection (0 week) as well as 4,7,12,16 and 20 weeks post infection,and stimulated with SEA for 72 hours in culture.The concentrations of Th1 cytokines (IFN-γand IL- 12) and Th2 cytokines (IL- 4,IL-10 and IL-13) in the culture supernatants were measured by sandwich ELISA.The levels of SEA-specific IgG antibody and its subtypes (IgG1 and IgG2a) were measured in mouse sera by ELISA.Pathological changes of hepatic granuloma in mice were determined by hematoxylin and eosin (H&E) staining.After the infection,the levels of Th1 cytokines,IFN- γ and IL 12,in ICOSL- KO mice were higher than those in wild-type C57BL/6J mice.However,the levels of Th2 cytokines (IL- 4,IL- 10 and IL- 13) were significantly decreased in ICOSL-KO mice compared to those in wild-type C57BL/6J mice.The levels of SEA-specific IgG antibody and its subtypes (IgG1 and IgG2a) in the sera of ICOSL- KO mice were also significantly lower than those of wild -type C57BL/6J mice.Moreover,the Th2 differentiation index was lower in ICOSL- KO mice than in wild-type C57BL/6J mice at 4,7,12,16 and 20 weeks post-infection.Similarly,the ratio of IgG1/IgG2a in ICOSL-KO mice was significantly lower than that in wild- type C57BL/6J mice at 7,12 and 16 weeks post- infection.Furthermore,throughout the course of disease progression,the volume of hepatic egg granuloma in ICOSL- KO mice was significantly smaller than that in wild-type C57BL/6J mice.In conclusions,there is a substantially down-regulated Th2 immune response in ICOSL- KO mice infected with Schistosoma japonicum,thus results in an attenuated hepatic lesion caused by egg granulomas.The findings indicate that the ICOS ICOSL co-stimulatory pathway plays an important role in the hepatic egg granuloma formation of schistosomiasis.

Effect of calcium channel blockers and actin depolymerizing/stabilizing agents on the survival of Schistosoma japonicum treated with praziquantel in vitro / 中国人兽共患病学报

To explore the action target of praziquantel (PZQ) and its underlying mechanism of action, adult male worms of Schistosoma japonicum were collected from the hepatic vein of Kunming mice infected at least 6 or more weeks previously with single-sex cercariae of S.japonicum by perfusion method. These worms were subjected to the action of calcium channel blockers (CCBs) or actin depolymerizing/stabilizing agents interfering with function of the calcium channel. The adult male worms in DMEM culture medium were co-cultivated with near-lethal dose of PZQ(14 μmol/L) overnight(16 hours).Then, the parasites were washed 3 times with sterile physiologic saline next morning after cultivation, re-suspended in new and drug-free medium and then observed under stereo-microscopy during the following 5 days. The experimental results showed that majority of adult male worms of S.japonicum were killed by the action of PZQ in a dose of 14 μmol/L in vitro under normal condition; while the worms pre-incubated with the actin depolymerizing agent cyto chalasin D (CyD) were able to survive in the condition containing 14 μmol/L of PZQ with a survival rate of 100%, and the worms pre-incubted with CCBs, such as nitrendipine and nifedipineu showed a survival rate of about 50% under the same condition. The results of this study suggest that the calcium channel of Schistosomes may be involved in the action target of PZQ and its underlying mechanism.

Dynamics of Liver Granuloma and the Relative Changes of Th1/Th2 Cytokine Levels in Mice Infected with Schistosoma Japonicum / 复旦学报（医学版）

Purpose To oberve the dynamics of liver granuloma and the relative changes of Thl/Th2cytokine levels in mice infected with Schistosoma japonicum, and investigate the role of Th1/Th2 in S.japontcum granuloma formation and regulation. Methods Liver granuloma measurement were performedby histological examination and the ELISA were used for the quantitative determination of IL-2, IFNr andIL-4 in murine serum and spleen lymphocyte culture medium at 0,4,6,8,10 and 12 wk after infection.Results At 6 wk liver granuloma formation appeared and at 8 wk liver granuloma peaked. After 12 wk livergranuhoma diminished obviously. Meanwhile, at 4 - 6 wk IL-2, IFNr and IL-4 began to rise, at 8 wk thelevels of Th1 cytokines IL-2 and IFNγ peaked and then declined, and at 8 wk the levels of Th2 cytokines IL-4 were rapidly enhanced and increased obviously with a prolongation of the infection duration.Conclusions The Th1cytokines IL-2 and IFNγ were correlated well with S. japonicum granulomaformation and vigour, and the Th2 cytokines IL-4 might play an important role in down-regulating egggranuloma reaction at chronic schistosomiasis by inhibiting the Th1cytokines.

Progress of research on therapy evaluation of schistosomiasis / 中国血吸虫病防治杂志

This review summarizes the progress of therapy evaluation of schistosomiais with immunology methods and expects the application foreground of nucleic acid detecting methods.

Cloning and expression of the gene encoding hypoxanthine-guanine phosphoribosyltransferase of Schistosoma japonicum / 中国血吸虫病防治杂志

Objective To perform the cloning of the gene encoding Schistosoma japonicum Chinese-strain hypoxanthine-guanine phosphoribosyltransferase(HGPRT)and its expression in Escherichia coli.MethodsA couple of primers were designed with the BamHI restriction endonuclease site introduced in forward primer and SalI in reverse primer.Total RNA was isolated from adult worms of S.japonicum Chinese-strain(Anhui-strain,Sjc-A)and the SjcHGPRT gene was amplified by reverse transcriptase-polymerase chain reaction(RT-PCR).The PCR product and the prokaryotic expression vector pET28a were digested by both restriction endonucleases BamHI and SalI.The target DNA fragments were purified and cloned properly into pET28a.After identification by en-donucleases digestion,PCR and sequencing,the recombinant plasmid pET28a-SjcHG PRT was transformed into competent E.coli BL21 and expressed in the presence of IPTG.Results pET28a-SjHGPRT was sequenced and shown to be 99% and 83% identical in deduced amino acid sequence to that of S.japonicum Chinese-strain(Hunan-strain,Sjc-H)and S.mansoni HGPRT,respectively.The results of SDS-PAGE and Western blot revealed that the molecular weight of expressed protein was around 30 kDa and could be recognized by anti-His-G-HPR antibody and sera from mice and human with schistosomasis japonica.Conclusion The recombinant plasmid containing SjcHGPRT cDNA is successfully constructed and its expression protein(reSjcHGPRT)is also successfully purified.

STUDIES ON THE EFFECT OF IMMUNOENHANCING REAGENT “425” ON EGG GRANULOMA FORMATION IN MICE INFECTED WITH SCHISTOSOMA JAPONICUM / 中国寄生虫学与寄生虫病杂志

Fourteen-34 days after Schistosoma japonzcum-infected mice were injected intraperitoneally with immunoenhancing reagent,Chinese angelica root extract ("425"),the specific antibody (IgG) levels were significantly higher in Group Ⅲ (362.67?162.21-480.00?289.45) than the control group (66.67?39.68-245.33?101.56) in experiment one,and in Gronp Ⅱ(488.00?320.38-768.00?267.38) than the control group (256.00?189.07-394.67?141.06) in experiment two.The egg granulomatous formation were markedly diminished in the injected mice.The ratios of granulomas vs.eggs' mean diameters of Group in of mice were 5.24?1.04-3.95?0.77 and those of the control group were 6.59?1.19-5.29?0.94 in experiment one,those of the group Ⅱ were 3.75?0.71-4.15?0.73 and those of the control group were 4.94?0.81-5.36?0.97 in experiment two.Meantime the egg antigen levels in the injected mice might be lower.This study shows that the control of immunomodulation of granulomatous formation in the hosts injected with immunoenhance reagent "425" can be induced.