Dendritic cells act as the major antigen presenting cells in the body and play a central role in intri-guing the adaptive immune response. Protective immunity against schistosome and immuno-pathological response in host caused by eggs are both closely associated with Th2 response. Further understanding on immune mechanism will contribute to the development of vaccines against schistosome infection, as well as the relief of the pathological lesion in schistosomiasis. This article discusses the central role of dendritic cells in the mechanism of Th2 response induced by schistosome (including eggs).

Objective To observe the destroyed architecture of splenic lymphoid follicles in mice infected with Schistosoma japonicum by immunohistochemistry. Methods The mice infected with S. japonicum(20 cercariae/mouse)for 8 weeks were sacrificed,and the splenic samples were paraffin embedded and sliced. The sections were first stained by hematoxylin and eosin to observe the massive structure of splenic lymphoid follicles,and then B cells,follicular dendritic cells(FDC)and germinal center cells were labeled with anti-B220,anti-CD21 or anti-Ki67 antibodies respectively by immunohistochemistry to observe the distribution of the specific cells of lymphoid follicles. Results The results of HE staining showed that the structure of lym-phoid follicles in spleens of infected mice was blurred,the number and area of follicles were significantly reduced compared to those of the normal mice. The immunohistochemical staining showed that the splenic T/B lymphocyte segregation ,FDC network and germinal centers of the infected mice all disappeared. Conclusion The structure of splenic lymphoid follicles in the mice infected with S. japonicum is obviously damaged.

Cryptosporidium spp.are protozoan parasites that infect the epithelial cells of the gstrointestinal tract of hosts.In humans,cryptosporidiosis is usually a self-limiting infection in immunocompetent individuals,but severe diarrhea and dissemination to extra-intestinal sites can occur in high-risk individuals,such as the very young,the elderly,immunedeficiency individuals,particularly in HIV-positive patients.So far,molecular epidemiological data have confirmed the presence of 30 species and over 40 genotypes with genus Cryptosporidium,with 21 species and genotypes being found in humans.The majority of human cryptosporidiosis cases are responsible for C.hominis and C.parvum.Human cases caused by C.meleagridis,C.ubiquitum,C.felis and C.canis have been increasing.Besides that,with data accumulation of molecular epidemiology of human cryptosporidiosis,some more Cryptosporidium species and genotypes were newly identified in humans.This paper mainly reviews epidemiology status of these new emerging Cryptosporidium species and genotypes in humans.

OBJECTIVE To study the possibility of air sterilization with solution of camphor leaves. METHODS Every six adjacent sickrooms that had same volume from 9 different clinical sectors were randomly selected for testing.Air of all sickrooms were sterilized by atomizing with solution of camphor leaves that was rough made by boiling and filtering and by direct irradiating with ultraviolet ray respectively.And then screened the sterilization effect of two methods respectively by air culture. RESULTS After sterilization with 100% solution of camphor leaves,all sickrooms were in line with standard of class Ⅲ(500 CFU/m~3),and 70% sickrooms were in line with class Ⅱ(200CFU/m~3).Both atomizing with solution of camphor leaves and direct irradiating with ultraviolet ray showed obvious effect,the result of air culture indicated that CFU of microorganisms were significant differrent between pre-sterilization and post-sterilization in both methods(P0.25). CONCLUSIONS Camphor leaves are very effective for sterilization and deserve to spread.

To preliminarily study the pro⁃angiogenic activity of Echinococcus granulosus hydatid cysts against hu⁃ man umbilical vein endothelial cells in vitro and the transcriptional level of potential pro⁃angiogenic factors. Methods The hydatid cysts and protoscolex derived from experimentally infected mice were collected and cultured in vitro，then the human umbilical vein endothelial cells were stimulated by the supernatant and cyst fluid respectively，and the angiogenesis was observed and analyzed through a microscope and the angiogenesis mode of the software NIH Image J. Meanwhile，the mouse homologous proteins of matrix metalloproteinase⁃9（MMP⁃9）and high mobility group box B1（HMGB1）were identified in E. granulosus genome through sequence alignment，and their transcriptional levels in the cyst wall and protoscolex were analyzed. Results The culture supernatant of hydatid cysts significantly promoted human umbilical vein endothelial cells into tubes（F = 73.03，P < 0.001），the transcriptions of MMP⁃9 and HMGB1 were detected in the cyst wall and protoscolex，and the transcriptional level of MMP⁃9 was higher in protoscolex（t = -11.65，P < 0.001），while the level of HMGB1 was higher in hydatid cysts（t = 6.43，P = 0.003）. Conclusion Some parasite⁃derived pro⁃angiogenic molecules may exist in the supernatant of E. granulosus hydatid cysts，while further researches are required into their exact mechanisms.

Objective:To analyze the causes, influencing factors and trends of dead on arrival cases in children′s Hospital in the past 5 years, aiming to provide direction and basis for reducing the dead on arrival cases of children.Methods:We collected the dead on arrival cases in the department of emergency at Shanghai Children′s Hospital from January 2015 to December 2019, classifed and analysed the gender, age, native place, death season, time of death, and possible causes of death, and then studied the correlation between above factors and the cases.Results:A total of 151 dead on arrival cases were collected.The annual number decreased year by year, and boys were more than girls in gender.Most of them were infants under 1 year old, and nonlocal children were more than Shanghai native.The above differences were statistically significant, but there was no significant difference in the distribution of death season and death time.In terms of the cause of death, perinatal diseases accounting for 33.8%(51/151), those accompanied with severe underlying diseases accounting for 39.1%(59/151), accidental death accounting for 14.6%(22/151), unexplained deaths accounting for 12.6%(19/151). Those distribution differences were statistically significant( χ2=32.497, P<0.001). Meanwhile, there were statistic differences in gender and age of the cases with severe underlying diseases( χ2=4.898, P=0.027; χ2=32.169, P<0.001), and the year and age distributions of the accidental death cases also had significant differences( χ2=16.636, P=0.002; χ2=14.727, P=0.002). Conclusion:To reduce dead on arrival cases of children, we should do a good job in perinatal health care and screening, reduce premature birth and birth defects, actively conduct propaganda to prevent children′s accidental injuries, popularize medical first aid knowledge, and strengthen children′s transport system.

Objective To study the relationship between Nogo-B and transforming growth factor-β1 (TGF-β1)/Smad2 signaling pathway in mice models of hepatic fibrosis.Methods Twenty four healthy male ICR mice were divided into two groups,with 6 in the control group and 18 in the model group.Mice in the model group were further divided into three subgroups according to different time points:subgroups of 4,8 and 12 weeks,with 6 mice in each subgroup.Hepatic fibrosis of mice was induced by subcutaneous injection of carbon tetrachloride (CCl4).The histopathologic changes of the liver were observed by optical microscope using hematoxylin-eosin and Masson trichrome stainings of the liver tissues.Expressions of Nogo-B,Smad2 and TGF-β1 mRNA and proteins in liver were detected by reverse transcription-polymerase chain reaction (RT-PCR),Western blot and immunohistochemistry assays,respectively.Means among groups were compared by univariate analysis of variance.Results The hepatic fibrosis models were successfully induced by CCl4 injection.The expressions of two subtypes of Nogo-B,Nogo-B1 and Nogo-B2 mRNA in normal livers were 0.140±0.050 and 0.104±0.023,but both significantly increased in the livers of mice in the 12 week model subgroup (1.054±0.040 and 0.500±0.057,F=431.41 and 135.46,respectively; both P＜0.01).The Nogo-B protein was mainly expressed in nonparenchymal cells of the liver,and was hardly expressed in hepatocytes.Linear correlation analysis showed that the expressions of Nogo-B mRNA and proteins were positively correlated with Smad2 and TGF-β1 mRNA and proteins (all P＜0.01),which were considered to participate in the signaling pathway of hepatic fibrosis.Conclusion Nogo-B might play a role in the development and progression of hepatic fibrosis by participating in TGF-β1/Smad2 signaling pathway.

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.

Objective To clone and express the gene encoding Schistosoma japonicum myophilin-like protein (SjcMLP) and to study the antigenicity of the recombinant protein. Methods The SjcMLP gene was amplified by PCR. The PCR product was cloned into T vector, and then subcloned into expression vector pQE30. The recombinant plasmid of pQE30-SjcMLP was transformed into E.coli M15, and induced with IPTG for expression. The bacterial lysis was conducted by ultrasonication and the supernatant was analysed by SDS-PAGE. The recombinant protein (reSjcMLP)was purified with the Ni-NTA resin, and analysed with SDS-PAGE and Western blot. The titers of sera from C57BL/6 mice immunized subcutaneously with reSjcMLP were detected by ELISA. Results The results of SDS-PAGE and Western blot showed that the molecular weight of expressed fusion protein was around 24.8 kDa and was recognized by the sera from the mice infected with Schistosoma japonicum. The purified protein of reSjcMLP was coated for ELISA test and the IgG titers in the sera from the mice immunized with reSjcMLP were as high as 1∶12 800 reacted with. However, no significant difference was found in worm reduction rates between the immunized mice and control mice. Conclusions The fused recombinant protein of reSjcMLP is successfully ex-pressed and purified. The recombinant protein in this experiment fails to induce significant protection against the challenge infection in C57BL/6 mice.

Ohjective To investigate the associations between the Arg389Gly polymorphism of the β_1-adrenergiecreceptor gene (ADRB1) and vasovagal syncope (VVS) in Chinese children. Methods Genotype of ADRB1 was determined by polymerase chain reaction-restriction fragment length pelymorphism analysis. Case-control studies and quantitative trait analysis were carried out by comparing between carriers (one or two copies of the Gly389 allele) and non-carriers (Arg389 genotype) of the ADRBI in 54 patients with unexplained syncope and in 54 healthy control subjects. Patients were subdivided into two groups according to head up tilt test (HUTT) : positive HUTT, known as VVS group and negative HUTT group. Distribution of Arg389Gly genetype in VVS group and the relationship to three clinical patterns were also analyzed. Results An allele frequency of Arg389 was 73.15% and Gly389 was 26.85% in healthy subjects. Higher Gly389 allele frequency was found in VVS group (n = 30) than that in negative HUTT group (33.33% vs. 14.58%, P < 0.05). In VVS group, the frequencies of the Gly389 allele in cardioinhibitory pattern (n = 6), mixed pattern (n = 9) and vasodepressor pattern (n = 15) was 66.67%, 33.3% and 23.33%, respectively, which had significant differences between the cardioinhibitory pattern from any of the other two patterns (both P < 0.05). Conclusions An association of positive HUTT with a single nucleotide pelymorphism of Gly to Arg switch at position 389 of the ADRB1 was found. This polymorphism may contribute to susceptibility to VVS.