Table of Content

28 February 2003, Volume 21 Issue 1

Previous Issue    Next Issue

论著

Impact of a Reservoir Project on Schistosomiasis Transmission in Lake Region

ZHANGJian-hua;HUFei;GUANChun-lin;HONGXian-lin;LINDan-dan;NINGAn;LIUYuemin;HULinsheng;ZHANGShao-ji

2003, 21(1):  4-11. 

Asbtract ( )   PDF (294KB) ( )  

Related Articles | Metrics

　Objective To determine the impact of a project of building dike for storing water on schistosomiasis transmission in Junshan Lake. Methods Junshan Lake in Jinxian County of Jiangxi Province was selected as survey pilot. Data on snail distribution and historical prevalence of schistosomiasis before building dike were collected. The water level inside and outside of the dike was recorded from 1995 to 2002, and the relationship between the water level and snail population at the inside of the dike was analyzed. Survey was made in a natural endemic village to confirm the current endemicity of schistosomiasis. Results In the selected area of Junshan lake, schistosomiasis was prevalent in 6 villages of 3 townships, with a snail area of 1 394 030 m² (2 090 Chinese Mu). Snails distributed mainly in the marshland at an elevation of 16.6-17.2 m, and the average infection rate of schistosomiasis in the residents was 12.5% in 1958 before the dike project. In 1960, two years after the dike was built, no living snails were found on the marshland, and the infection rate of schistosomiasis in the residents reduced remarkably. Curently, no schistosomiasis cases were found in human being and cattle in the surveyed village. Conclusion The reservoir project had helped the elimination of snails and interrupted schistosomiasis transmission.


Cloning and Expression of Specific Antigen Genes of Ancylostoma caninum

GUOXiang-rong;XUEHai-chou;LITie-hua;LIUSen

2003, 21(1):  5-15. 

Asbtract ( )   PDF (368KB) ( )  

Related Articles | Metrics

　Objective To search for the gene encoding specific antigen of Ancylostoma caninum that induces host′s protective immunity. Methods A lambda ZAPⅡ cDNA library of A.canium was screened with sera from dogs immunized subcutaneously with hookworm larvae(L3). After sequencing, insert gene (AcAg) from positive clones was ligated into PUC18 and PET28C. Recombinant pET28C plasmid was induced to expressed protein in the E.coli BL21. The characteristic of recombinant protein is analyzed by SDS-PAGE and Western bloting assay. Results Five positive clones were obtained, and proved to be the same. The insert gene (AcAg) in pET28C vector expressed a recombinant protein of about 43 kDa. Using Western bloting assay, this protein was recognized by the sera from dog immunized with Ancylostoma caninum third stage infected larvae and used for screening library. Conclusion The AcAg, which exhibits 35% homologous to Caenorhabditis elegans gene unc-89, is a novel specific antigen of A.caninum. Its ability to elicit the protective immunity and the probability of the recombinant protein as a vaccine need to be further evaluated.


Prokaryotic Expression and Characterization of an Antigenic Gene of Adult Trichinella spiralis

ZHUXin-ping;YANGJing;YANGYa-ping;PascalBoireauZHANBinFENGJian-jun;PeterHotez

2003, 21(1):  6-19. 

Asbtract ( )   PDF (393KB) ( )  

Related Articles | Metrics

　Objective To obtain a purified Ts87 gene expression product of adult Trichinella spiralis and identify its immunogenicity. Methods Ts87 cDNA was subcloned into PET-28a(+) expression vector. The transformed bacteria bearing PET-28a(+)/Ts87 plasmids were induced by IPTG for production of fusion proteins. The expression product purified with His binding affinity chromatography and electro elution assay was analyzed by SDS-PAGE, ELISA and Western blot, and was used to immunize the rabbits. Results PET-28a(+)/Ts87 transformed bacteria produced the desired fusion protein with a relative molecular weight of 40 kDa. The antisera with high titer were obtained by immunizing rabbit with Ts87 recombinant protein. Ts87 expression protein was detected as positive reaction with infected rabbit sera, infected swine sera and antisera against Ts87 by ELISA. Ts87 protein was also recognized by above-mentioned sera with Western blotting. However, Ts87 protein failed to react with the patient sera infected with Cysticercus cellulosae or Echinococcus granulosus, and rabbit sera infected with Schistosoma japonicum. Conclusion A new Trichinella recombinant protein with specific antigenicity was obtained.


Identification of Taenia saginata by mtCOⅠ in Four Areas of Yunnan and Guizhou Provinces

WANGZheng-rong;BAOHuai-en

2003, 21(1):  7-23. 

Asbtract ( )   PDF (326KB) ( )  

Related Articles | Metrics

　Objective To identify the types of Taenia saginata isolated from Dali of Yunnan Province, and from Duyun and Congjiang of Guizhou Province. Methods Genomic DNA was isolated, and the mitochondrial cytochrome C oxidase subunitⅠ(mtCOⅠ) genes were amplified by polymerase chain reaction(PCR) and analyzed by PHYLIP software package. Results The mtCOⅠgene sequences of Lanping sample were identical to that of T.saginata asiatica known in Taiwan, and the samples obtained from Dali and Duyun showed the same mtCOⅠgene sequences, while the sample from Congjiang had the same mtCOⅠgene sequences as T.saginata . The homology between these two groups of gene sequences was 97.44%, while the homology of amino acid sequences reached to 99.16%. The constructed phylogenetic tree revealed that the relationship between T.saginata asiatica and T.saginata is closer, both are distant relative to T.solium and other species of cestodes. Conclusion The Taenia prevalent in Lanping, Dali and Duyun is identified as T.saginata asiatica , while that isolated in Congjiang is the typical T.saginata.


Protective Effect Against Schistosoma japonicum of Recombinant Fusion Protein SjGST-32 in Mice

TIANMing-li;CAIChun;YIXin-yuan*;ZENGXian-fang;ZHANGShun-ke

2003, 21(1):  8-26. 

Asbtract ( )   PDF (376KB) ( )  

Related Articles | Metrics

　Objective To explore the optimal immune doses of recombinant antigen rSjGST-32, with QuilA as adjuvant. Methods BALB/c mice were immunized with doses of 50, 100 and 200 μg rSjGST-32/mouse plus 50 μg QuilA adjuvant. QuilA and PBS were used as controls. Levels of specific antibodies were detected by ELISA. The mice were challenged 4 weeks after last vaccination. Worms and eggs collected from the livers of mice were counted 45 days after challenge. Results As compared with the control groups, the worm reduction rate in the 50, 100 and 200 μg experiment groups was 38.1%, 47.8% and 48.8%, respectively. The reduction rate of liver eggs per gram (LEPG) was 39.1%, 53.5% and 53.6%, respectively, and the reduction rate of the liver eggs per female (LEPF) was 22.5%, 22.8% and 21.8%, respectively. The specific antibody titers in sera reached 1∶51 200, 1∶102 400 and 1∶102 400, respectively before challenge. Conclusion The results show that for vaccinating BALB/c mice, the optimal antigen dose is 100 μg of recombinant rSjGST-32 plus QuilA adjuvant.


Taxonomic Status in DNA Sequences of Five Species of Genus Paragonimus

CUIAi-li;CHANGZheng-shan;CHENMing-gang;DavidBlair;CHENShao-hong;ZHANGYong-nian;FENGZheng

2003, 21(1):  9-30. 

Asbtract ( )   PDF (337KB) ( )  

Related Articles | Metrics

　Objective To analyze the taxonomic status of Paragonimus hokuoensis, P.paishuihoensis, P.menglaensis, P.bangkokensis and P.xiangshanensis in Genus Paragonimus Braun, 1899. Methods DNA sequences were obtained from the ITS2 and COⅠ genes and phylogenetic trees were built from these. Results There are some DNA sequence differences among P.paishuihoensis, P.menglaensis, P.bangkokensis and P.xiangshanensis, but the differences are small. P.hokuoensis and P.skrjabini are similar in DNA sequence. Conclusion P.paishuihoensis, P.menglaensis, P.bangkokensis and P.xiangshanensis are closer in the genetic relationship. Their taxonomic status lies between P.skrjabini and P.westermani. The genetic relationship between P.hokuoensis and P.skrjabini is very close.


Observation on the Amount of Oxygen Consumption by Oncomelania hupensis under Low Tempterature

HONGQing-biao;ZHOUXiao-nong;HANGDe-rong;SUNLe-ping;YANGGuo-jing;HUANGYi-xin;YANGKun

2003, 21(1):  10-33. 

Asbtract ( )   PDF (306KB) ( )  

Related Articles | Metrics

　Objective To observe hibernation phenomena of Oncomelanai hupensis and explore the way of inducing the hibernation in laboratory. Methods Snails, O.hupensis hupensis, were collected from marshland of Jiangsu. The snail hibernation was induced by the way of cultivation at a mimic natural environment in the laboratory with gradually changing temperature. The amount of oxygen consumed by snails was tested by iodine titration, and their hibernation was tested by pin puncture followed by warm water. Results There was no significant difference on the rate of snail hibernation when the temperature was reduced by 1 ℃ per 24 hrs and by 1 ℃ per 48 hrs. The hibernation rate increased} with the decreasing temperature. There was a significant regression relationship between hibernation rate and temperature with R+2=0.967 (F=207.72, P<0.01). The temperature for 50% snails at hibernation (ET-50) was at 5.87 ℃ with 95% confidence limit of 5.32-6.23 ℃. The amount of oxygen consumed by snails declined with reduced temperature, there was a significant regression relationship between oxygen consumption and temperature with R+2=0.963 (F=182.18, P<0.01). A significant regression relationship was also shown between oxygen consumption and hibernation rate (R²=0.916, F=75.88, P<0.01). Conclusion Snail hibernation can be induced by the way of gradually decreasing temperature, and pin puncture or warm water resuscitation can be used to determine the status of snail hibernation.


Cloning and Characterization of Mitochondrial NADH Dehydrogenase Gene of Cysticercus cellulosae

ZHANGLi;LIUDian-wu*

2003, 21(1):  11-36. 

Asbtract ( )   PDF (265KB) ( )  

Related Articles | Metrics

　Objective To clone and characterize the NADH1 gene of Cysticercus cellulosae. Methods A cDNA library was constructed from Cysticercus cellulosae and was immunoscreened by using rabbit anti Cysticercus cellulosae polyclonal antibody. The gene structure and its possible function were analyzed by comparing with sequences available in the GenBank, after the insert of positive clone was subcloned and the nucleotide sequence of the insert was determined} by dideoxynucleotide chain termination method. Results and Conclusion A cDNA clone (named TS5) with a length of 1 082 bp was isolated. The 5′ terminal of cloned gene contained one open reading frame of 1-578 bp encoding 192 amino acid residues of mitochondrial NADH dehydrogenase subunit 1 and the 3′ terminal contained three kinds of tRNA genes.


Intranasal or Intragastric Vaccination of Mice with Recombinant Schistosoma japonicum Ferritin Induces Immune Protection Against Challenge Infection

HUANGFu-shen*;YIXin-yuan**;ZENGXian|fang;LUOXiu|ju;ZHANGShun|ke;CAIChun

2003, 21(1):  12-41. 

Asbtract ( )   PDF (432KB) ( )  

Related Articles | Metrics

　Objective To test the immune protection against challenge infection in mice vaccinated intranasally or intragastrically with recombinant Schistosoma japonicum (S.j) Ferritin (rSjFer). Methods Mice were divided into 8 groups each with 10 mice. They were immunized intragastically with rSjFer, CTB, rSjFer+CTB and intranasally with rSjFer, CTB and rSjFer+CTB respectively. PBS was used intragastically or intranasally as control groups. The mice were challenged with 40±1 S.j cercariae per mouse 2 wk after the third vaccinization. Forty|five days later, mice were killed and perfused, and the adult worms and eggs were counted. Serum and fecal samples were obtained before the first immunization} and the challenge infection. IgA and lgG in sera and sIgA in feces were detected by ELISA. Results The worm reduction rate was 3.98%, 3.77%, 25.57% in the intragastric vaccination groups and 7.59%, 4.50%, 33.35% in the intranasal vaccination groups respectively. The egg reduction rate was 3.76%, 2.46%, 34.75% and 4.40%, 0.06%, 60.10% respectively. Conclusion This study showed that a significant immune protection against Schistosoma} japonicum infection was induced by mucosal (intranasal and intragastic ) vaccination with rSjFer.


Study on the Level of Specific IgG, IgG1 and IgE During Anaphylactic Shock in Sheep Induced by Echinococcus granulosus

ZHENGHong;XUZhi-xin_;YangGe-xiong;WENHao

2003, 21(1):  13-45. 

Asbtract ( )   PDF (401KB) ( )  

Related Articles | Metrics

　Objective To investigate the change of specific antibodies IgG, IgG1 subclass and IgE in sheep infected with Echinococcus granulosus(E.g) during anaphylactic shock, and to observe antigen B reactivity against IgG antibody in E.g|infected sheep. Methods Antigen B and crude antigen were prepared with E.g cyst fluid (EgCF) from infected sheep. The enzyme|linked immunosorbent assay(ELISA) was used for detecting the level of specific IgG, IgG1 and IgE during anaphylactic shock in sheep induced by E.g. Results The level of specific IgG, IgG1 and IgE was significantly higher in the infected sheep after 6 months than that of the uninfected control group (P<0.01). The IgE level decreased rapidly after anaphylactic shock induced, especially when the sheep was dying. Following an antigen challenge the sheep showed a general decrease in total IgG and IgG1 subclass. The total IgG showed a slight change at the beginning,followed by a decrease 1 h after challenge. The decrease of IgG1 subclass was more significant than the total IgG in 40 min after challenge injection. The positive rate was 91% for antigen B and 32% for crude antigen of EgCF against IgG antibody in E.g|infected sheep. Conclusion The specific IgE plays a major role in the anaphylactic shock, while IgG and IgG1 antibodies are also important. Antigen B derived from sheep E.g cyst fluid appears to be useful in serodiagnosis of and monitoring on the infection status in sheep.