Table of Content

30 December 2007, Volume 25 Issue 6

Previous Issue    Next Issue

述评

Malaria Situation in the People′s Republic of China in 2006

ZHOUShui-sen;WANGYi;TANGLin-hua

2007, 25(6):  1-441. 

Asbtract ( )   PDF (145KB) ( )  

Related Articles | Metrics

Totally 64 178 malaria cases and 52 082 suspected cases with 38 deaths were reported by the annual case reporting system in 917 counties of 23 Provinces/Municipality/Autonomous Regions （P/M/A） in 2006， and the annual incidence was 0.50/10 000. Through the internet reporting system 60 382 malaria cases were reported from 1 097 counties of 30 P/M/A. The number of malaria cases and the rank of P/M/A were basically in concordance in the two systems.
Among the 917 counties with reported malaria cases， 29 counties with an incidence more than 10/10 000 distributed in Yunnan （15 counties）， Hainan （6）， Anhui （7）， Henan （1）. There were 76 counties in which the malaria incidence was between 1/10 000 and 10/10 000.
3 469 Plasmodium falciparum malaria cases accounted for 5.4% of the total cases， of which 60.4% （2 097） were imported cases in 206 counties/cities of 17 P/M/A. Indigenous falciparum malaria was found in 38 counties/cities of Yunnan and Hainan Provinces， of which 26 counties/cities were in Yunnan， and 12 counties/cities were in Hainan， decreased by 5 and 4 respectively in comparison to that of 2005.
Focal outbreaks occurred in 183 villages of 16 counties in Yunnan， Anhui， Henan and Guizhou Provinces. 3 058 malaria cases from the outbreaks accounted for 4.8% of the total reported cases.
Although a considerable decrease in malaria incidence was contributed to the implementation of the Global Fund Programme， Yunnan and Hainan Provinces were still relatively high transmission areas. Yunnan ranked No.2 in the country in terms of the number of cases， while Hainan ranked down to No.2 by malaria incidence for the first time after ranking No.1 for years. 19 385 malaria cases were reported from the two provinces in 2006， accounting for 30.2% of the total reported cases in the country. There were 15 532 cases with 32 deaths reported from Yunnan， the incidence was 3.89/10 000， a decrease of 21.4% than that in the last year. Among the reported cases， 3 090 were falciparum malaria with 60.4% imported cases. The number of reported cases in Hainan was 3 858， with an incidence of 4.65/10 000， 14.8% decrease than the last year.
In central China， the re-emergence of malaria was considerable in provinces along the Huai River， especially in the provinces of Anhui and Henan. Not only the number of malaria cases but also the incidence in Anhui became the No. 1 in the country in 2006. 34 984 malaria cases and 11 064 suspected cases were reported from Anhui in 2006， accounting for 54.5% of the total cases in the country， with an incidence of 6.4/10 000 increased by 113% than that in 2005. The number of reported cases in Henan was 5 093， increased by 86.7% in incidence. Hubei Province reported 1 782 cases with an incidence of 0.31/10 000， increased by 14.8%. 767 cases were reported from Jiangsu Province， a slight increase than that in 2005.
Cases reported from other P/M/A occupied about 3.4% of the total. Several hundreds were reported from each of Guizhou， Sichuan， Guangdong， Zhejiang， Shandong and Shanghai. Less than 100 cases were reported from each of Guangxi， Fujian， Jiangxi， Hunan， Chongqing， Liaoning， Shaanxi， Shanxi， and Gansu in 2006.
In summary， malaria is still an important problem of public health in the country， especially in the southern and central parts. Yunnan and Hainan still faced a severe situation of malaria endemic with the spread of Plasmodium falciparum， particularly the imported malaria cases in 25 border counties in Yunnan. In the central parts of the country， especially in Anhui Province the malaria prevalence increased considerably with the highest incidence and over half of the total malaria cases in 2006， rank of P/M/A were basically in concordance in the two systems, which revealed new challenges to the National Malaria Control Program in China.

论著

Prokaryotic Expression of Trichinella spiralis Gene Ts21 and Identification of the Recombinant Protein

WANGZhong-quan;LULi;CUIJing;WANGLai;;WANGRui

2007, 25(6):  2-446. 

Asbtract ( )   PDF (305KB) ( )  

Related Articles | Metrics

Objective To express the antigen gene Ts21 of Trichinella spiralis， purify the recombinant protein and test its antigenicity. Methods T. spiralis gene Ts21 was subcloned into the prokaryotic expression vector pMAL-c2X and the recombinant pMAL-c2X-Ts21 was constructed. The recombinant plasmid was transformed into E. coli TB1 strain and induced by IPTG. The expression products were purified by MBP-binding affinity chromatography. The antigenicity of the recombinant protein was examined by SDS-PAGE and Western blotting. Mice were immunized with the recombinant protein， the titer of the immune sera was detected by ELISA. The distribution of Ts21 protein in muscle larvae was observed by IFA. Results The molecular weight of the expressed fusion protein was about Mr 63 500 and the expression level peaked at 4 h post-incubation. The portion of the fusion protein accounted for 18.2% of all the protein by thin-layer gel optical scanning. Western blotting demonstrated that the recombinant protein was recognized by sera from mice infected by T. spiralis （T1） and T. nelsoni （T7） as well as sera of patients with trichinellosis， but not by sera from mice infected with T. nativa （T2）， T. britovi （T3） and T. pseudospiralis （T4）. The recombinant protein did not react with sera from patients with ancylostomiasis， cysticercosis and schistosomiasis， but cross-reacted with sera from patients with paragonimiasis， clonorchiasis and echinococcosis. High titers of antibodies were produced in mice immunized with the recombinant protein. IFA showed that the Ts21 protein was mainly distributed in the cuticle of muscle larvae. Conclusion The Ts21 antigen gene of T. spiralis has been expressed and the recombinant protein shows antigenicity.

Expression and Antigenicity Analysis of NTPase Gene of Toxoplasma gondii

SHADan;TANFeng;PANChang-wang;LIANGShao-hui*

2007, 25(6):  3-450. 

Asbtract ( )   PDF (243KB) ( )  

Related Articles | Metrics

Objective To clone and express prokaryotic recombinant plasmid of nucleoside triphosphate hydrolase （NTPase） gene of Toxoplasma gondii， and analyze its antigenicity. Method NTPase gene was amplified by PCR from RH strain of T. gondii and cloned into pGEM-T Easy vector. Positive clones were screened and identified by BglⅡ, HindⅢ digestion and sequenced. The target gene was then subcloned into prokaryotic expression vector pBAD-HisB and transformed into E. coli BL21（DE3）. The expressed recombinant protein was purified with Ni-NTA agarose and further analyzed by sodium dodecyl sulfate polyacrylamide gel electropheresis （SDS-PAGE） and Western blotting. Results NTPase-Ⅱ gene was specifically amplified， and the homology of DNA sequence was 100％ to that in the GenBank. SDS-PAGE showed that the recombinant NTPase protein with correct molecular weight was expressed highly in E.coli BL21（DE3）. Western blotting testified that the purified recombinant protein could be specifically recognized by mouse serum immunized with T. gondii and mouse anti-recombinant protein serum. Conclusion The NTPase-Ⅱ gene has been cloned and expressed in E.coli BL21（DE3）， and the purified protein of NTPase-Ⅱ gene displays a specific antigenicity.

Multiplex PCR for Analysis of the Plasmodium falciparum Drug Resistance Molecular Markers

ZHANGGuo-qing;TANGLin-hua;GUANYa-yi;ZHOUShui-sen;ZHENGBin;HUANGFang;WUSong;LIUYan

2007, 25(6):  4-456. 

Asbtract ( )   PDF (329KB) ( )  

Related Articles | Metrics

Objective To develop a multiplex PCR protocol for amplification of five Plasmodium falciparum drug resistance related genes， thereby facilitate the rapid and high throughput analysis of the drug resistance molecular markers. Methods Five pairs of primers were designed according to the reference sequences by using Primer Premier 5.0 and Oligo 6.0 software. Drug resistance related genes， including P. falciparum chloroquine resistance transporter （Pfcrt）， multi-drug resistance 1 （Pfmdr1）， dihydropteroate synthetase （Pfdhps）， dihydrofolate reductase （Pfdhfr） and sarco/endo-plasmic reticulum Ca ²⁺-ATPase（PfATPase6）， were amplified by single-tube multiplex PCR using Hot Start Taq DNA Poly-merase among negative controls （P. vivax， P. berghei， P. cynomolgi， Leishmania donovani， Cryptosporidium andersoni），blank control （using H₂O as template）， as well as P. falciparum laboratory isolates （3D7， Dd2， HB3， FCC1/HN and CMH/YN） and field samples （collected from Yunnan， Hainan of China and Myanmar）. After amplification， the PCR products were analyzed by agarose gel electrophoresis. The sequencing results were aligned to the reference sequence using BLAST. Results Five expected bands at 315， 437， 514， 594 and 770 bp were obtained with no additional or nonspecific products in P. falciparum laboratory isolates and field samples. The sequencing results were identical with the reference sequence except the polymorphism sites， and exhibited more than 98.5% homology. The multiplex amplification was performed successfully starting from 0.1 ng of DNA template. No band was observed in negative controls and blank control. Conclusion The present study establishes a method to amplify five Plasmodium falciparum drug resistance related genes harboring 21 SNPs by one-tube reaction. The multiplex PCR protocol showing high specificity and sensitivity is more convenient and efficient in analyzing the P. falciparum drug resistance molecular markers as compared with traditional nested PCR.

Density Fluctuation of Microfilariae and the Role of Residual Infection Source in Filariasis Transmission after its Interruption

DUANJi-hui;LUOHeng-qiao;ZHANGKai-ren;ZHANGMing;ZENGXiang-wei;LIZheng-xiang;PENGXin-rong;XIANGYuan-yin;SUNDe-jian;WUWei-ping

2007, 25(6):  5-461. 

Asbtract ( )   PDF (278KB) ( )  

Related Articles | Metrics

Objective To investigate the density fluctuation of microfilariae， persistence of microfilaremia and possible new infection due to residual microfilaremia in areas with filariasis transmission interrupted. Methods The observation site was made in a village of Jishou City， Hunan Province. Inhabitants were regularly examined by thick blood smear and the density fluctuation of residual microfilaremia in known and newly-found cases were followed up. With a consent from the cases with residual microfilaremia, no treatment was given until they naturally turned negative. Antifilarial antibody level was detected by IFAT and a test kit for filariasis-special IgG4. Culex quinquefaciatus was dissected to determine the natural infection rate and density of III stage filarial larvae in transmission season. The identified cases were followed-up by interviews and physical examinations to see if clinical manifestations appeared. Results Blood examination was carried out for all inhabitants for 10 times， 4 cases with microfilaremia， including 3 cases found at the beginning of the project and one newly infected case, were discovered after the interruption of filariasis transmission in the 19-year period. Among the 4 cases followed up， one case naturally turned negative within 7 years， one case became negative in the 9th year but returned positive in the 12th year， and then naturally turned negative in the 13th year. The 3rd case turned negative in the 14th year and was again positive in the 19th and the 20th years， and became negative through diethylcarbamazine （DEC） treatment in the 21st year. The new case was found to have microfilaremia in the 16th year and kept positive for 5 years until DEC treatment. Serological tests （IFAT and special IgG4） revealed no new positive cases. The natural infection rate and larvae density in Culex quinquefasciatus decreased annually. Conclusion The persistence period of residual microfilaremia in individual cases might last for more than 20 years after filariasis transmission has been interrupted.

Pathological Change in Hydatid Cysts of Echinococcus granulosus Treated with High Intensity Focused Ultrasound

WANGJun-an;ZOUXiao-yi;YEBin;ZHANGCheng-wu;ZHAOFa-sheng

2007, 25(6):  6-465. 

Asbtract ( )   PDF (339KB) ( )  

Related Articles | Metrics

Objective To investigate the pathological change in Echinococcus granulosus hydatid cysts treated with high intensity focus ultrasound （HIFU）. Methods Thirty cysts with thinner wall and proper elasticity, taken from livers of infected sheep， were randomly divided into three groups. By cyclical multilayer radiation around the cyst wall，two experiment groups were treated with HIFU under 150 W and 250 W sound power respectively. The control group was treated by ordinary ultrasound for 2 min. Results The inner cyst wall of hydatid treated with HIFU became curved，thicker， stiffer， white and less transparent. The germinal layer was detached mostly from the laminated layers of hydatid in the experiment groups. Images from the transmission electron microscopy showed that in the experiment groups fabric texture of hydatid changed significantly and germinal cells were broken. Conclusion HIFU in a model of cyclical multilayer radiation causes pathological damage of the E. granulosus hydatid.

Experimental Infection of Sarcocystis suihominis in Pig and Human Volunteer in Guangxi

LIJin-hui;LINZhen;DUJin-fa;QINYe-xin

2007, 25(6):  7-468. 

Asbtract ( )   PDF (222KB) ( )  

Related Articles | Metrics

Objective To confirm existence of Sarcocystis suihominis and possible transmission cycle between human and pigs. Methods Based on the human-pig-human infection cycle of Sarcocystis suihominis ， feces of naturally infected pigs were collected and over 10 000 sporocysts were received by flotation technique， which were mixed with fodder to infect a normal pig. Fresh pork meat containing mature sarcocysts was chopped into pieces and swallowed by a volunteer （the first author of this paper） with about 71 000 sporocysts. Symptoms and development of the parasites after infection were observed. Results The volunteer showed abdominal distension in about 5 hours after infection， with watery diarrhea 13 times from the 8th to 36th hour， vomiting 4 times， chilling and fever with a temperature of 38.5℃， dizziness， headache， joint and muscle ache， epigastralgia， and anorexia. Unsporized sporocysts were found in the faces 10 days after infection and sporocysts appeared on the 12th day. The average size of sporocysts was 11.9（8.8-14.5）μm×9.2（7.5-12.5） μm. The infected pig showed a slight anorexia， fatigue， constipation， hair loosen in 5～8 days after infection， and returned normal on the 17th day. The average size of the sarcocysts was 299.2（175-575）μm×62.3（30-102.5）μm. Size of bradyzoites was 11.5（9.5-13.5）μm×4.1（2.8-5.0）μm. The volunteer was treated with acetylspiramycin for 15 days（0.2 g/time， 4 times/d） after 46 days of infection， and fecal examination turned negative 30 days later. Conclusion There is a man-pig cycle for Sarcocystis suihominis in Guangxi.

Parasite-origin IgE-dependent Histamine-releasing Factors in Inducing Histamine Release from Sensitized Mast Cells

CHENXiao-xiang;HUXu-chu;XUJing;YUXin-bing*

2007, 25(6):  8-473. 

Asbtract ( )   PDF (346KB) ( )  

Related Articles | Metrics

Objective To obtain the recombinant IgE-dependent histamine-releasing factors of Schistosoma japonicum and Clonorchis sinensis （rSjHRF and rCsHRF） and to study the effect of recombinant HRFs to induce histamine release from sensitized rat mast cells. Methods The complete coding regions of SjHRF and CsHRF were cloned separately， and the recombinant plasmids were respectively transformed and expressed in BL21 cells. The soluble recombinant rSjHRF and rCsHRF were purified. Aliquots of the mast cells obtained from the lungs of OVA-immunized rats were separately incubated with rSjHRF and rCsHRF and the released histamine was measured by the OPT spectrofluorometric procedure. The dose-dependent curves and the kinetics of histamine release induced by rSjHRF and rCsHRF were prepared. Results The recombinant plasmids pET-30-rSjHRF and pET-30-rCsHRF were constructed successfully and the purified soluble recombinant proteins rSjHRF and rCsHRF were obtained by affinity chromatography. rSjHRF and rCsHRF induced histamine release from sensitized mast cells in a dose-dependent manner. At the concentration of 150 mg/L， the average rate of histamine release from sensitized mast cells induced by rSjHRF and rCsHRF were 49.78% and 32.63%， respectively. Histamine release increased with prolonged reaction time and the maximal release occurred at 35min. Conclusion The recombinant parasite-originated IgE-dependent HRFs show an effect of inducing histamine release from sensitized mast cells， suggesting that this protein would play a role in type I hypersensitivity in hosts with parasitic infections.

实验研究

Genetic Variation of Two Mitochondrial DNA Molecules from Three Isolates of Oncomelania hupensis

HUYing;LIXue-ming;LINRui;NIUAn-ou;HUWen-qing

2007, 25(6):  9-477. 

Asbtract ( )   PDF (297KB) ( )  

Related Articles | Metrics

Objective To study the genetic variation of two mitochondrial DNA molecules (CO1 and Cytb gene) of Oncomelania hupensis isolated from different areas. Methods Snails were collected from Jingxi of Guangxi，Yueyang of Hunan and Eryuan of Yunnan. Genomic DNA was extracted from the snails，Co1 and Cytb gene fragments were amplified by PCR，then purified and sequenced. Sequences of each isolates were edited by using Clustal W(1.82) software，and the nucleotide composition，transition and transversion were accounted by using MEGA(3.1) software. The genetic distances were computed with Kimura method and phylogenetic trees were constructed with UPGMA and MP method respectively. Results CO1 and Cytb gene fragments were about 700 bp and 600 bp(including 2 primers) respectively. A total of 106 mutation spots (15.9%) were tested in CO1 homological nucleotides，and 165 mutation spots (28.5%) were tested in Cytb homological nucleotides. The distance matrix between Guangxi isolate and Hunan isolate was 0.051 and 0.031 for CO1 gene and Cytb gene respectively；while that between Guangxi and Yunnan isolates was 0.158 and 0.405 respectively. Phylogenetic trees constructed by UPGMA and MP took on the similar topo-structure：isolates of Guangxi and Hunan clustered into one group，while the Yunnan isolate exhibited as another group. Conclusion Oncomelania hupensis in Guangxi，Hunan and Yunnan are of relatively rich polymorphism in CO1 and Cytb genes in general.

Primary Culture of the Cells from Oncomelania hupensis Liver

YEQing;ZHUJun-yong;ZHONGQin-ping;JIANGMing-sen;DONGHui-fen*

2007, 25(6):  10-482. 

Asbtract ( )   PDF (364KB) ( )  

Related Articles | Metrics

Objective To develop a method for primary culture of cells from Oncomelania hupensis liver， and to observe the distribution of succinate dehydrogenase （SDH） and lactate dehydrogenase （LDH） in the cultured cells. Methods O.hupensis was anatomized to separate the liver. Livers were soaked in 0.2% benzalkonium bromide and washed by physiological saline containing antibiotics in turns. Cells from the liver were harvested by mechanical mulling and filtering. The isolated cells were then incubated with methods of the combination culture and standing suspension culture， respectively. The culture medium for the cells was a mixture of Medium 199 （50 ml）， 0.3% lactoalbumin hydrolysate dissolved in a balanced salt solution （BBS，30 ml）， and fetal calf serum （FCS，20 ml） containing a moderate amount of antibiotics （100 IU/ml penicillin， 100 μg/ml streptomycin and 50 μg/ml kanamycin） at pH 7.2-7.4 under the temperature of 26.5 ℃. The cells were stained by using Giemsa and Pearson methods （for SDH and LDH respectively） to observe the shape of cultured cells and enzyme distribution in cells. The living and stained cells were microscopically observed. Results Under microscope， the attached cells incubated with method of the combination culture showed round， elliptic， triangular and irregular shapes, with more round and elliptic cells. The size was approximately （4-16）μm×（6-20）μm in average. The clustered cells with an unclear nucleus and abundant and lucid cytoplasm were smaller than diffused cells with a large， obvious nuclei and less cytoplasm. Degeneration was observed after culturing for 5-7 days. The cultured cells could be divided into two types based on the color shown after Giemsa staining. The first type cells showed blue cytoplasm and mauve nuclei while the second type cells were opposite. There were blue granules in different sizes and shade in the cytoplasm after SDH and LDH staining. It was difficult for the cells to attach the wall of the culture flask using method of the standing suspension culture. The shape of the cultured cells were almost round with unclear nuclei， and the size was about （4-6）μm×（6-8）μm in average. The cells incubated with the standing suspension method were found to be contaminated after culturing for 3 days. Conclusion The combination culture method is suitable for primary culture of the cells from O.hupensis liver and the cells show activities of both SDH and LDH in cytoplasm.

Identification and Purification of Tyrophagus putrescentiae Allergens

HUANGZhi-jian;LIUZhi-gang

2007, 25(6):  11-487. 

Asbtract ( )   PDF (332KB) ( )  

Related Articles | Metrics

Objective To identify and purify the allergens of Tyrophagus putrescentiae. Methods Tyrophagus putrescentiae extract was analyzed by SDS-PAGE and Western blotting， and was partially purified by DE52 anion-exchange chromatography and HiLoad 16， 60 Superdex 200 prep grade Size-exclusion chromatography. Results 23 bands were found after SDS-PAGE with comparative molecular weight （Mr） of 177 000， 118 000， 107 000， 70 000， 67 000， 60 000， 52 000， 45 000， 41 000， 40 000， 38 000， 37 000， 35 000， 27 000， 23 000， 22 000， 18 000， 17 000， 16 000， 15 000， 14 000， 13 00 and 12 000. Five allergens were detected by Western blotting with Mr 128 000， 67 000-70 000， 36 000-37 000， 18 000 and 16 000， respectively. The positive reaction rate of 3 allergens， with Mr 128 000， 67 000-70 000 and 36 000-37 000， were 100%， while that of other 2 allergens with Mr 18 000 and 16 000 was 77.8% and 44.4% respectively。The allergen with Mr 18 000 was purified by anion-exchange chromatography and Size-exclusion chromatography. Conclusion Four major allergens and one minor allergen from Tyrophagus putrescentiae have been identified.

现场研究

Morphology and Habits of An. anthropophagus and its Role in Malaria Transmission in Hengqin Island of Zhuhai City

ZHENGXiang;TANGLin-hua;GUZheng-cheng;ZHUTai-hua;SHIWen-qi;JIANGWei-kang;ZHOUShui-sen;PANBo;LINRong-xing

2007, 25(6):  12-491. 

Asbtract ( )   PDF (285KB) ( )  

Related Articles | Metrics

Objective To study the morphology and ecological habits of An.anthropophagus and its role in malaria transmission in Hengqin Island of Zhuhai City， Guangdong Province. Methods Mosquitoes were captured through overnight/semi-overnight trapping with human and cattle baits as well as lamp-trapping. The specimens were morphologically identified through describing the adult mosquitoes， eggs and pupae. The relevant parameters were collected to calculate the vectorial capacity of both An.anthropophagus and An.sinensis. Results There is no morphological difference between the isolate of An.anthropophagus from Hengqin Island and that from Jiangsu Province. Its human blood preference ratio and human blood index was 0.94 and 0.75 respectively, and the vectorial capacity of ^{An.anthropophagus} was 7.36 times higher than that of An.sinensis （5.191 4/0.705 2）. Conclusion The isolate of An.anthropophagus from Hengqin Island belongs same species to that from the mainland, which prefers to human blood and shows higher malaria transmission potential.

综述

Study Progress on the Mode of Action of Praziquantel Against Schistosomes

XIAOShu-hua

2007, 25(6):  13-502. 

Asbtract ( )   PDF (409KB) ( )  

Related Articles | Metrics

Praziquantel is the only effective drug of choice against five huaman species of schistosomes. Main advantages of praziquantel include convenient oral administration, high safety and efficacy as well as short treatment course. To better understand the mode of action of praziqantel against schistosomes would be helpful for further development of new broad-spectrum anthelminthics. This paper summarizes the 30 years′ research progress on the mode of action of the drug against schistosomes proceeded by domestic and abroad laboratories.

Serial Analysis of Gene Expression in Parasitological Research

LIQiao-li;ZHANGZhi-ming;QIAOZhong-dong

2007, 25(6):  14-509. 

Asbtract ( )   PDF (303KB) ( )  

Related Articles | Metrics

Serial analysis of gene expression （SAGE） is a powerful high-throughput experimental technique that allows rapid， quantitative analysis of global gene expression in eukaryotic organisms. A short sequence taq （10~14 bp），which is defined by an anchoring enzyme site at a fixed distance from polyA tail， contains sufficient information to identify mRNA transcript from which it originates. The taqs are ligated to obtain concatemers that are cloned into a plasmid vector for sequencing. The identification and abundance of mRNA can be observed through bioinformatics and statistical analysis of a given tag. SAGE is not only applied in obtaining global profile of gene expression in a given cell or tissue， but also help identify a set of specific genes to the cellular conditions by comparing the profiles constructed for a pair of cells that are kept at different conditions. This review covers a general introduction of SAGE, its protocol， methodological evolution and applications in parasite biology.

学术争鸣

Distinquishment of Armillifer and a Correction on Pathogen Misidentification from a Reported Case

QIUMing-hua;JIANGYu-yan

2007, 25(6):  15-511. 

Asbtract ( )   PDF (172KB) ( )  

Related Articles | Metrics

A worm-like specimen recovered from a patient previously identified as Armillifer sp. in the city of Yulin，Guangxi Autonomous Region. After comparative analysis of habitat （serpents as final hosts and human being as accidental intermediate host） and body size of the 4 known pathogenic pentastomid species of Armillifer （A.agkistrodontis， A.armillatus， A.grandis and A.moniliformis） with the recovered specimen, the present authors consider that the recovered specimen has been misidentified as Armillifer sp. The recovered specimen probably belongs to a nasal leech.

研究简报

Endemic Situation of Schistosomiasis at the National Surveillance Sites of Nanjing， 2006

WEIDe-hui;GAOYuan;XIEChao;yong

2007, 25(6):  16-503. 

Asbtract ( )   PDF (176KB) ( )  

Related Articles | Metrics

Three endemic villages were selected as the national surveillance sites and Schistosoma japonicum infection in residents and livestock was investigated in 2006. The positive rate of serological （IHA） and stool examinations was 10.06%（307/3 053） and 0.13%（4/3 053） for local residents， 10.8%（7/65） and 0（0/7） for moving people respectively. No infected livestock was found.

A Modified Dye Test for Toxoplasma gondii Infection

XUHui*;NIAn-ping;CUIQing-tao;HAOYing

2007, 25(6):  17-512. 

Asbtract ( )   PDF (193KB) ( )  

Related Articles | Metrics

A modified dye test with microplate was to be established to detect Toxoplasma antibodies with cell-cultured Toxoplasma gondii. Numbers of stained and unstained tachyzoites were estimated in every 100 tachyzoites in each well after dyeing with methylene blue. The dilution with 50% tachyzoites stained was used as final dilution. Better results of the microplate dye test has been received when the concentration of tachyzoites in suspension reaches 109/ml with 1% sodium citrate as accessory factor.

Establishment and Application of Circulating Antigen Detection in Paragonimus westermani Infection

CHENShao-hong;LIHao;ZHOUXiao-nong

2007, 25(6):  18-515. 

Asbtract ( )   PDF (249KB) ( )  

Related Articles | Metrics

Circulating antigen and antibody were detected by CAg-dot-ELISA & CAb-ELISA respectively on the clinically confirmed patients of paragonimiasis, people in paragonimus endemic area, cases with early infection of P. westermani, and casess with other parasitic infections. Circulating antigen was detected in 29 out of 70 cases with paragonimiasis with a sensitivity of 41.5%. The rate of cross reaction in cases with clonorchiasis sinensis and schistosomiasis was 25% （5/20） and 20% （4/20）, respectively, and it was negative in 60 casess with other parasitic infections and healthy subjects, with an overall specificity of 93.6%. Specific antibody was detected in 67 of 70 cases with paragonimiasis with a sensitivity of 95.7%. The cross reaction rate in cases of clonorchiasis sinensis and schistosomiasis was 25%（5/20） and 20%（4/20）, but negative in 60 casess with other parasitic infections and healthy subjects, with a specificity of 92.1%. 220 persons from paragonimus endemic area were all negative in antigen detection and 7（3.2%） showed antibody positive. Dot-ELISA for circulating antigen detection may be helpful in diagnosing early infection of P. westermani.

Screening of Mimic Epitopes of Toxoplasma gondii Antigen by Phage-displayed Peptide Library

HEYan-yan;ZHANGShu-Yi;ZHUMin;QIANMin;TANHong-yan

2007, 25(6):  19-517. 

Asbtract ( )   PDF (234KB) ( )  

Related Articles | Metrics

Specific antibodies purified from sera of rabbit infected with Toxoplasma gondii were used to immunoscreen the 12-mer and 7-mer phage random peptide libraries. By 3 rounds of screening， 70 clones were picked out randomly to test the specificity and 43 were found positive by ELISA. 23 of the 43 positive clones showing strong reaction in ELISA were picked out for sequencing. Clone A7 was selected as mimic antigen in ELISA test after analysis of the 23 short peptide sequences. 23 out of 47 sera from rabbits infected with Toxoplasma gondii were ELISA positive by A7 mimic antigen with a positive rate of 68.1%， and 10 of 155 sera from healthy persons showed false positive with a specificity of 93.5%. The primary result suggests that mimic antigen may have a potential use in diagnose of toxoplasmosis.

Preliminary Investigation on Paragonimus in Lvchun County of Yunnan Province

YANGBin-bin;ZHOUBen-jiang;LIRu-qing;BAIZhong-wen;WUOu-bao;GAOXiu-fang

2007, 25(6):  20-519. 

Asbtract ( )   PDF (189KB) ( )  

Related Articles | Metrics

69 crabs were collected from Daxing, Gekui and Niukong townships of Lvchun county, Yunnan Province in 2006 and excysted metacercariae were only obtained from crabs of Niukong. The infection rate was 27.6% （8/29） with an average metacercaria number of 2.25 each crab. No encysted metacercariae were found. The excysted metacercariae were morphologically identified as Paragonimus proliferus.