1.EFFECT OF LEVO-PRAZIQUANTEL ON THE EXPOSURE OF TEGUMENTAL SURFACE ANTIGEN OF SCHISTOSOMA JAPONICUM
Chinese Journal of Schistosomiasis Control 1989;0(01):-
Mice infected with Schistosoma japonicum were treated with a single oral dose of levo-praziquantel 75mg/kg or racemic praziquantel 150mg/kg. 10min-7d after administration of the drugs, the infected mice were sacrificed and the parasites were studied. The tegumental antigen of the integral worms and of. the worm sections were tested by IFA.10-30 min after treatment more than 50% of the tegumental surface of adult worm showed weak and small fluorescent spots in treated groups. 1-6h after treatment, the sucker and extremity of adult worm showed brighter fluorescent spots. From 6h after treatment, there were very bright fluorescent spots on the whole worm surface. 3d after treatment, the fluorescent intensity was weaker than before, and there was no significant difference between the levo-praziquantel group and racemic praziquantel group in the exposure of tegumental surface antigen. The results demonstrated that levo-praziquantel, just like the racemic-praziquantel, could disturb the tegumental metabolic course of the schistosomes, caused tegumental damage and exposure of adult worm surface antigen.
2.Expression of viral infectivity factor protein of human immunodificiency viruses and its biological function
Yunzhi ZHANG ; Hong JIN ; Hongzhou LU ; Xunjia CHENG ; Xiaozhang PAN
Chinese Journal of Infectious Diseases 2008;26(4):231-234
Objectives To analyze the characteristic of HIV-1 viral infectivity factor (Vif) gene variants isolated from Shanghai. To construct the prokaryotic expression vector of HIV-1 vif gene and understand its immunogenieity. Methods HIV-1 vii genes were amplified and sequenced from 23 serum samples of HIV-1 infected patients in Shanghai and then compared with the international standard HIV-1 strain. Subsequently, these amplified Vif fragments were sub cloned into pETS2b(+)expression vector. The recombinant prokaryotie plasmids pETS2b (+)-HIV-1/Vif were then transferred into BL21DS(Star)cells for expressing and purifying HIV-1 Vif protein. HIV-1 Viff rat polyclonal antibody was then preparing by injecting the purified Vif proteins into the mice. ELISA was used to determine the purity of Vif proteins and the immunogenicity of its polyclonal antibodies. Results The nucleotide acid mutation rate of HIV-1 vif gene in Shanghai AIDS patient was (0. 179±0. 006)% compared with the international standard HIV-1 strain. Some similar mutations in vif gene were found in HIV-1 strains isolated from Shanghai while the amino acid sequence between 151 and 240 in Vif protein was conserved. The construction of HIV-1 Vif prokaryotic expression plamids and the preparation of Vif polyclonal antibodies were successfully done in this study. The reaction between recombinant HIV-1 Vif protein and the serum from HIV-1 infected patient was not significantly different from that between the recombinant protein and healthy control serum(P>0.05). HIV-1 Vif polyclonal antibody reacted differently with recombined HIV-1 Vif protein compared with healthy control serum samples (t=178.61, P<0.01). Conclusions The Vif gene mutation rate is high in HIV-1 strains isolated from Shanghai compared with international standard HIV-1 strain. The prokaryotic expression plasmids of HIV-1 vif antigen are successfully constructed and Vif polyclonal antibodies are prepared well.
3.Merging medical humanities into the teaching of human parasitology
Hongxia SHAO ; Yong ZENG ; Jinye LIU ; Jianhua SUN ; Xunjia CHENG
Chinese Journal of Medical Education Research 2006;0(09):-
It was introduced in this paper the concrete measures of medical humanistic education which is in harmony with the teaching of human parasitology. The necessity of humanistic education for the medical students in the present age and the feasibility of humanistic education in basic medical education were discussed according to the feedback on the survey of the medical students. This study aimed to explore an ideal teaching model for medical humanistic education and comprehensively improve the humanistic accomplishment in medical students.
4.The Probe into and Reform of Teaching Methods in Human Parasitology for Basic Medicine Students
Hongxia SHAO ; Zuohua MAO ; Shujun ZHOU ; Jianhua SUN ; Xunjia CHENG
Chinese Journal of Medical Education Research 2003;0(04):-
To meet the need of cultivating high-quality medical talents for the 21 century,enlighten the thoughts and strengthen the practice and operation ability of medical students,we have probed and reformed our teaching methods in human parasitology for basic medicine students directing at the weak points in our traditional teaching.Moreover,we have conducted the survey among the students for three years on end so as to provide a consultation for improving our teaching methods and quality.
5.ANALYSIS OF PATHOGENICITY OF ENTAMOEBA HISTOLYTICA BY POLYMERASE CHAIN REACTION
Xunjia CHENG ; Tachibana HIROSHI ; Kobayashi SEIKI ; Kaneda YOSHIMASA ; Meiyu HUANG
Chinese Journal of Parasitology and Parasitic Diseases 1987;0(03):-
DNA from five isolates of Entamoeba histolytica were examined for their pathogenicity by polymerase chain reaction. Three isolates SH-3,SH-6,SH-8 were isolated from patients with acute amoebic dysentery, whereas SH-5 and SH-7 were isolated from asymptomatic cyst passers. Gel electrophoresis of PCR products showed that primers P11 , P12 for pathogenic strains could amplify genomic DNA extracted from SH-8 , and primers P13, P14 for non-pathogenic strains could amplify genomic DNA extracted from SH-3, SH-5, SH-6 and SH-7. Furthermore, zymodeme analysis and the reactivity of McAb 4G6, which recognizes the 30 kDa antigen of pathogenic E. histolytica indicated that only SH-8 was pathogenic, while the others were nonpathogenic. The results of the genotypic analysis by PCR were in accord with the phenotypic properties.It is suggested that there are differences in genomic DNA between pathogenic and non-pathogenic strains. PCR is a highly sensitive and specific method for genomic DNA analysis of E. histolytica.
6.Screening and Expression of Recombinant Human Monoclonal Antibody Fab Fragments Specific to Entamoeba histolytica
Qing SHU ; Hongxia SHAO ; Tachibana HIROSHI ; Xunjia CHENG
Chinese Journal of Parasitology and Parasitic Diseases 1987;0(02):-
Objective To prepare recombinant human monoclonal antibody Fab fragments specific to the surface antigen of Entamoeba histolytica. Methods Total RNA was isolated from lymphocytes which were separated from an asymptomatic E. histolytica cyst carrier. The genes of IgG light chain and Fd region of heavy chain were amplified by a reverse transcriptase PCR and ligated with a plasmid vector. After the genes were introduced into Escherichia coli, the clones expressing Fab fragments specific to the surface antigen of E. histolytica were screened and the product was purified. Results Thirty thousand clones were screened and one of them was proved positive to the surface antigen of E. histolytica. Conclusion This study demonstrated that the bacterial system can be used to produce recombinant human monoclonal antibody Fab fragments specific to the surface antigen of E. histolytica and they may be applicable for the future diagnosis and treatment of the infection.
7.Clinical features and genetic sequences of severe fever with thrombocytopenia syndrome bunyavirus in a new-epidemic region of Zhejiang Province, China
Shibo LI ; Chuan XUE ; Xianjun DING ; Ruiding LIU ; Hongyi XUE ; Zhendong TONG ; Nengming CHAI ; Yekai WANG ; Zhiyi LIN ; Xunjia CHENG
Chinese Journal of Infectious Diseases 2012;30(5):268-272
ObjectiveTo investigate the clinical characteristics,epidemiology of patients with severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) infection and genetic sequences of SFTSV.MethodsClinical data of five cases of severe fever with thrombocytopenia syndrome (SFTS)from Zhoushan Hospital during May 2011 to July 2011 were retrospectively analyzed.SFTSV gene was amplified by polymerase chain reaction (PCR).CD3+ CD4+ and CD3+ CD8+T lymphocytes were detected by flow cytometry (FCM).The sequences of isolated SFTSV strains were compared with those in GenBank. ResultsThe symptoms of continuous high fever,sore muscles,enlarged superficial lymph nodes,abdominal pain,diarrhea with gastrointestinal hemorrhage were observed.The white blood cells,platelets and CD3+ CD4+ T lymphocytes were progressive decreased in acute phase with the minimum of (0.97-2.00) × 109/L,(12-42) × 109/L and 7.52%-20.39%,respectively.The SFTSV was isolated from the sera of two patients.The sequences were compared with SFTSV sequences in GenBank.The homology of RNA-dependent RNA polymerase gene was 96% compared with BX-2010,L-WWG,LN3,JS4,SD4,HN6 and AH12; the glycoprotein gene was 94% ; N protein gene was 95% compared with JS4,SD4 and LN4.The homology of the above three genes between two isolates was 99%.ConclusionsOur results suggest that SFTSV is sporadic in Zhejiang Province which is probably from native epidemic focus.SFTS is progressive and severe with acute onset.Multiple organ dysfunction is common in severe eases.
8.Various brain-eating amoebae: the protozoa, the pathogenesis, and the disease.
Frontiers of Medicine 2021;15(6):842-866
Among various genera of free-living amoebae prevalent in nature, some members are identified as causative agents of human encephalitis, in which Naegleria fowleri followed by Acanthamoeba spp. and Balamuthia mandrillaris have been successively discovered. As the three dominant genera responsible for infections, Acanthamoeba and Balamuthia work as opportunistic pathogens of granulomatous amoebic encephalitis in immunocompetent and immunocompromised individuals, whereas Naegleria induces primary amoebic meningoencephalitis mostly in healthy children and young adults as a more violent and deadly disease. Due to the lack of typical symptoms and laboratory findings, all these amoebic encephalitic diseases are difficult to diagnose. Considering that subsequent therapies are also affected, all these brain infections cause significant mortality worldwide, with more than 90% of the cases being fatal. Along with global warming and population explosion, expanding areas of human and amoebae activity in some regions lead to increased contact, resulting in more serious infections and drawing increased public attention. In this review, we summarize the present information of these pathogenic free-living amoebae, including their phylogeny, classification, biology, and ecology. The mechanisms of pathogenesis, immunology, pathophysiology, clinical manifestations, epidemiology, diagnosis, and therapies are also discussed.
Amebiasis/epidemiology*
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Balamuthia mandrillaris
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Brain
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Central Nervous System Protozoal Infections/epidemiology*
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Child
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Humans
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Naegleria fowleri
9.Current status and prospect of biomarker research for schizophrenia
Mengyuan ZHU ; Qing CHEN ; Dan LI ; Mengxia WANG ; Renyu WANG ; Yuxin ZHU ; Weifeng JIN ; Shuzi CHEN ; Ping LI ; Zhenhua LI ; Peijun MA ; Shuai LIU ; Qiong GAO ; Xiaoyan LOU ; Jie XU ; Lili ZHU ; Ling ZHAO ; Kangyi LIANG ; Jinghong CHEN ; Xunjia CHENG ; Ke DONG ; Xiaokui GUO ; Qingtian LI ; Yun SHI ; Junyu SUN ; Huabin XU ; Ping LIN
Chinese Journal of Laboratory Medicine 2022;45(11):1191-1196
Schizophrenia is a serious mental disease. The diagnosis of schizophrenia so far relies heavily on subjective evidence, including self-reported experiences by patients, manifestations described by relatives, and abnormal behaviors assessed by psychiatrists. The diagnosis, monitoring of the disease progression and therapy efficacy assessment are challenging due to the lack of established laboratory biomarkers. Based on the current literature, clinical consensus, guidelines, and expert recommendations, this review highlighted evidence-based potential laboratory biomarkers for the diagnosis of schizophrenia, including genetic biomarkers, neurotransmitters, neurodevelopmental-related proteins, and intestinal flora, and discussed the potential future directions for the application of these biomarkers in this field, aiming to provide an objective basis for the use of these biomarkers in the early and accurate diagnosis, treatment, and prognosis and rehabilitation assessment of schizophrenia.
10.Filamentation initiated by Cas2 and its association with the acquisition process in cells.
Lei WANG ; Xin YU ; Mengjie LI ; Guiqin SUN ; Lin ZOU ; Tiansheng LI ; Linlin HOU ; Yameng GUO ; Danfeng SHEN ; Di QU ; Xunjia CHENG ; Li CHEN
International Journal of Oral Science 2019;11(3):29-29
Cas1-and-Cas2-mediated new spacer acquisition is an essential process for bacterial adaptive immunity. The process is critical for the ecology of the oral microflora and oral health. Although molecular mechanisms for spacer acquisition are known, it has never been established if this process is associated with the morphological changes of bacteria. In this study, we demonstrated a novel Cas2-induced filamentation phenotype in E. coli that was regulated by co-expression of the Cas1 protein. A 30 amino acid motif at the carboxyl terminus of Cas2 is necessary for this function. By imaging analysis, we provided evidence to argue that Cas-induced filamentation is a step coupled with new spacer acquisition during which filaments are characterised by polyploidy with asymmetric cell division. This work may open new opportunities to investigate the adaptive immune response and microbial balance for oral health.