Table of Content

30 June 2013, Volume 31 Issue 3

Previous Issue    Next Issue

Comparative Observation on Inhibition of Hemozoin Formation and Their in vitro and in vivo Antischistosome Activity Displayed by 7 Antimalarial Drugs

XUE Jian1，JIANG Bin1，LIU Cong-shan1，SUN Jun2，XIAO Shu-hua1*

2013, 31(3):  1-161-169. 

Asbtract ( )   PDF (1193KB) ( )  

Related Articles | Metrics

Objective  To observe and compare the inhibition of hemozoin formation and the in vitro as well as in vivo antischistosomal activity induced by seven antimalarial drugs.  Methods  Inhibition of hemozoin formation displayed by chloroquine phosphate，　quinine hydrochloride，　quinidine，　mefloquine hydrochloride，　pyronaridine phosphate and lumefantrine at 25 μmol/L，　and artemether at 100 μmol/L was performed by assay of inhibition of β-hematin formation in 1 mol/L sodium acetate buffers containing hematin with various pH of 4.0， 4.2， 4.4， 4.6， 4.8，　and 5.0. In in vitro antischistosomal study， the medium of RPMI 1640 supplemented by 10% calf serum was used to maintain the adult Schistosoma japonicum， and the 50% and 95% lethal concentratrions（LC50 and LC95） to kill the adult worms of each drug were then determined. Meanwhile，　the interaction of quinine，　pyronaridine and chloroquine combined with hemin against adult schistosomes was also undertaken. As to in vivo test， the efficacy of seven antimalarial drugs administered orally or intraperitoneally to mice infected with adult schistosomes was observed.  Results  In the acidic acetate-hematin solution， 25 μmol/L pyronaridine showed significant inhibition of β-hematin formation at pH 4.4-5.0 with inhibition rates of 81.3%-97.0%. At pH 4.6， the inhibition rates of β-hematin formation in acetate-hematin solution induced by mefloquine， chloroquine or quinine at concentration of 25 μmol/L were 79.7%， 72.8% or 65.8%， respectively， and the β-hematin formation was continually inhibited by these 3 antimalarial drugs at pH 4.8 and 5.0 with inhibition rates of 83.1%-90.6%， 41.9%-49.0% or 53.2-62.0%. The inhibition rates of β-hematin formation at pH 4.6 and 4.8-5.0 induced by lumefantrine 25 μmol/L were 74.3% and 40.4%-40.5%， respectively. While under the same concentration of quinidine， 53.4% and 50.9% inhibition rates of β-hematin formation were observed at pH 4.8 and 5.0. As to artemether， higher concentration of 100 μmol/L only showed light inhibition of β-hematin formation at pH 4.4-4.8 with inhibition rates of 16.6%-25.0%. As regard to in vitro test， the LC50 and LC95 of mefloquine， pyronaridine， quinine and quinidine were 4.93 and 6.123 μg/ml， 37.278 and 75.703 μg/ml， 93.688 and 134.578 μg/ml， as well as 101.534 and 129.957 μg/ml，respectively. When adult schistosomes were exposed to the medium containing chloroquine， lumefantrine or artemether at higher concentrations of 100 or 120 μg/ml for 72 h， no or only individual worms died. Hence the LC50 and LC95 of these 3 drugs could not be determined. In other in vitro test， adult schistosomes exposed to quinine 50 μmol/L（20 μg/ml） in combination with 153.4 μmol/L（100 μg/ml） hemin， all worms died within 72 h post incubation. While the worms exposed to 50 μmol/L（26 μg/ml） chloroquine combined with the same concentration of hemin，　only 18.8%（3/16） of worm died at 72 h post exposure. Unexpectedly， in schistosomes exposed to pyronaridine at a toxic concentrations of 50 μmol/L（46 μg/ml） in combination with 153.4 mol/L（100 μg/ml） hemin for 72 h， all of the worms were protected from the toxic action induced by pyronaridine， which revealed in normal motor activity and appearance of morphology in majority of the worms. In in vivo test， mice infected with adult schistosomes were treated orally with chloroquine， pyronaridine or lumefantrine at a daily dose of 400 mg/kg for 3 days， or intraperitoneally with chloroquine or pyronaridine at a daily dose of 100 mg/kg for 2 or 3 days， no apparent efficacy was seen. When mefloquine，　quinine， quinidine or artemether were administered orally to infected mice at a single dose of 400 mg/kg or 200 mg/kg（mefloquine），　all groups of mice treated showed moderate or higher efficacy with worm burden reductions of 61.1%-98.1%.  Conclusion  Among the seven antimalarial drugs tested， their inhibitions of hemozoin（β-hematin） exhibit no definite correlation to their in vitro and in vivo antischistosomal activity. Quinine in combination with hemin shows synergistic effect against schistosomes in vitro. While antagonist effect is observed in pyronardine combined with hemin.

Eukaryotic Expression of SjE16, SjPPIase and SjRobl Genes from Schistosoma japonicum Egg and Evaluation of Their Role in Immunodiagnosis

CHEN Qing, WU Chen-yun, FENG Yan, WU Jian-hua, YAO Xin-ying，XU Da-gang, WANG Zhao-jun*

2013, 31(3):  2-170-175. 

Asbtract ( )   PDF (1272KB) ( )  

Related Articles | Metrics

Objective  To express Schistosoma japonicum egg proteins by eukaryotic system and evaluate their role in schistosomiasis immunodiagnosis.  Methods  S. japonicum egg RNA was extracted and reversed to cDNA. Egg specific or highly expressed genes: SJCHGC01695（SjE16）, SJCHGC00856（SjIMA8）, SJCHGC06249（SjTOR）, SJCHGC06324（SjP40）, SJEFTD02（SjSLP）, SJCHGC06679（SjPPIase） and SJCHGC06529（SjRobl）, were amplified and sub-cloned to eukaryotic expression vector pPIC9K. Recombinant vectors were transformed to yeast GS115 and the recombinant yeast was induced by methanol. Proteins were purified with Ni-NTA affinity chromatography and analyzed by SDS-PAGE and Western blotting. For the detection of specific antibodies, the wells of microtiter plate were coated with soluble egg antigen （SEA）, SjE16, SjPPIase and SjRobl, respectively, or combination of recombinant proteins. The specific antibody reactivity in sera from schistosome-infected mice and patients were examined by ELISA.  Results  The highly expressed genes from S. japonicum eggs were cloned by PCR. The recombinant proteins of SjE16, SjPPIase and SjRobl were expressed and identified by SDS-PAGE and Western blotting. Those recombinant SjE16, SjPPIase and SjRobl were recognized by IgM and IgG in schistosome-infected mouse and patient sera. The sensitivity of the three antigens in detecting IgM and IgG in acute patients were 80%, 60%, 80% and 40%, 80%, 70%, respectively, while that of the combination of SjE16 and SjRobl in detecting IgM was 100%.  Conclusion  The above three S. japonicum egg enriched proteins were expressed using eukaryotic expression system and can be used in acute schistosomiasis diagnosis.

Microglial Activation and Inflammatory Cytokine Expression in the Brain of Chronic Toxoplasma gondii-infected Mice

ZHANG Yi-hua1，WANG Lu2，WANG Xue-long1 *，SHEN Ji-long1，ZHANG Qian1，KONG Lan-ting1，WANG Wei-wei1，CHEN He1

2013, 31(3):  3-176-179. 

Asbtract ( )   PDF (1310KB) ( )  

Related Articles | Metrics

Objective  To investigate microglial activation and inflammatory cytokine expression in chronic Toxoplasma gondii infection.  Methods  Thirty mice were randomly divided into chronic T. gondii infection group and normal control group. Each mouse in infection group was infected orally with 30 cysts of the TgCtwh6 strain. Normal group received 0.3 ml normal saline. On the 60th day after infection， immunohistochemical staining was performed to assess the number of microglia and morphological change. The expression of inflammatory cytokines （IL-1β， IL-6， and TNF-α） was measured by RT-PCR. The expression of iNOS was determined by Western blotting and immunofluorescence.  Results  Immunohistochemistry analysis showed that the number of Iba-1 positive cells in the cortex and hippocampus of infection group （16.5±0.8 and 17.9±1.1） was higher than that of the control（8.4±0.2 and 10.3±0.8）（P<0.05）. Iba-1 positive cells （i.e. microglia） had larger cell bodies and ramified morphology. RT-PCR result indicated that mRNA level of IL-1β， IL-6， and TNF-α in infection group （0.862±0.169， 0.407±0.158， and 0.305±0.073） was significantly higher than that of the control （0.149±0.030， 0.037±0.008， and 0.001±0.001）（P<0.05）. The iNOS protein expression in infection group （0.252±0.164） was higher than that of the control（0.0433±0.004）（P<0.05）. Immunofluorescence demonstrated that iNOS protein released by activated microglia.  Conclusion  Chronic T. gondii infection caused micro-glial activation， which up-regulate the level of IL-1β， IL-6， TNF-α， and iNOS.

Development of an IMS-qPCR Method for Detection of Cryptosporidium parvum in Water

GAO Shan-shan1,2, WU Shao-qiang3, LUO Jing1, WANG Cheng-min1, ZHANG Min1,

2013, 31(3):  4-180-184. 

Asbtract ( )   PDF (1200KB) ( )  

Related Articles | Metrics

Objective  To develop a detection method for Cryptosporidium parvum oocysts from water samples, which combined immunomagnetic separation （IMS） with Taqman real-time PCR （qPCR）.  Methods  Conditions of sepa-ration and enrichment of IMS method by using specific streptavidin magnetic beads coated with monoclonal antibodies Cp23 directed against C. parvum oocysts were optimized. Special primers of PCR and Taqman probes were designed referring to the 18S rDNA gene of C. parvum（GenBank Accession No. AB513881.1）. The conserved genes were amplified from genomic DNA of C. parvum, and then cloned into Peasy-T1 vector. Tenfold dilutions of positive plasmids（104-108 copy/μl） were used to construct a standard curves by Taqman qPCR. The specificity of the assay was determined using genomic DNA of C. baileyi, Toxoplasma gondii, C. canis and Escherichia coli. The sensitivity of this assay was evaluated by analyzing 10-fold serially dilutions of plasmids ranging from 100 to 108 copy/μl. Both IMS-qPCR assay and indirect immunofluorescent-antibody assay（IFA） were applied to detect 50 water samples collected from the dairy cattle farms in Hebei.  Results  The optimal incubation concentration and time of antibody Cp23 were 20 ng/ml and 30 min, respectively, and the catching time was 30 min, the recovery rate was more than 95%. PCR product was 272 bp, and identified by restriction enzyme digestion and nucleotide sequencing. There was a good linear relationship between the standard plasmids and Ct value（correlation r2=0.996 1） of the Taqman qPCR. No cross-reactivity was observed with C. baileyi, T. gondii, C. canis and E. coli. The sensitivity of C. parvum-specific assay was 10 copy/μl. Compared with IFA as golden standard method, the specificity and sensitivity of IMS-qPCR for 50 water samples was 100%（18/18） and 93.8%（30/32）, respectively.  Conclution  The IMS-qPCR assay can be used to specifically detect C. parvum oocysts in water samples.

Species Identification of Echinococcus Isolates Collected from Canines and Tibetan Foxes in Chengduo County, Qinghai Province

FENG Kai1,2，HUANG Fu-qiang1,2，DUO Hong2，FU Yong2，SHEN Xiu-ying2，PENG Mao2，LI Wei2 *

2013, 31(3):  5-185-187. 

Asbtract ( )   PDF (1059KB) ( )  

Related Articles | Metrics

Objective  To identify Echinococcus isolates collected from Tibetan foxes（Vulpes ferrilata） and dogs in Chengduo county, Yushu Prefecture, Qinghai Province.  Methods  Six Tibetan foxes and 6 Tibetan dogs died accidently. Small intestines were dissected from the animals. The adult tap-worms were collected by sedimentation technique. The worms were stained with borax carmine and observed under microscope. The isolates were identified initially by morphololgy and the infection intensity for each animal was calculated. Eight isolates of E. multilocularis and 2 isolates of E. shiquicus were selected for the extraction of total DNA. The mitochondrion DNA COⅠ gene was amplified with specific primers by PCR, then sequenced and analyzed.  Results  E. multilocularis and E. shiquicus were found. Two out of 6 Tibetan foxes were infected with E. multilocularis, the infection intensity was 1 640 and 839. One Tibetan fox was infected by E. shiquicus with an infection intensity of 833. Two Tibetan dogs were infected with E. multilocularis, and the infection intensity was 10 195 and 78, respectively. The obtained partial sequences of COⅠ gene were 450 bp. The COⅠ gene from 8 isolates of E. multilocularis shared 100% homology with the isolates collected from Tibetan dogs in Sichuan Province（Accession No. AB461417）. The COⅠ gene from 2 isolates of E. shiquicus showed high sequence homology（99.2%） with the isolates collected from Ochotona curzoniae in Shiqu County, Sichuan Province（Accession No. AB159136）.  Conclusion  E. multilocularis and E. shiquicus have been identified in the small intestines of wild foxes, and E. multilocularis in Tibetan dogs.

Different Echinococcus granulosus Antigens Induced Indoleamine 2，3-dioxygenase Expression in Dendritic Cells

SHAN Jiao-yu1,2, LI Hai-tao1,3, LI Chun-yan2, XIAO Jin2, LI Liang1, ZHANG Xue1, LIN Ren-yong1, WEN Hao1,3 *

2013, 31(3):  6-188-192. 

Asbtract ( )   PDF (1044KB) ( )  

Related Articles | Metrics

Objective  To observe the expression of indoleamine 2, 3-dioxygenase （IDO） in dendritic cells　（DCs） via different Echinococcus granulosus antigens in vitro. 　Methods  Bone Marrow DCs generated from bone marrow precursor cells of C57BL/6 mice and cultured in the presence of recombinant mouse GM-CSF（rmGM-CSF）. Then, DCs were induced with 15 μg/ml recombinant antigen B （rAgB）, 5 mg/ml mouse hydatid fluid （MHF）, 1 000 U/ml IFN-γ （as positive control）, and RPMI 1640 complete medium（as negative control）, respectively. Meanwhile, the treated DCs and cell supernatants were collected at 18, 24 and 48 h after induction. The positive expressions of D40, CD80, CD86 and I-A/I-E on DCs were determined by flow cytometry. By real-time fluorescent quantitative reverse-transcription polymerase chain reaction（FQ-RT-PCR）, the expression level of IDO mRNA in DCs was measured. Concentrations of tryptophan （Try） were tested by high-performance liquid chromatography （HPLC） assay in cell supernatant.  Results  The data from flow cytometry showed that the positive expressions of CD40, CD80, CD86, I-A/I-E were decreased after stimulated by rAgB and MHF. At 24 h after induction, there was significant difference in the level of CD40, CD86 and I-A/I-E among rAgB-treated group ［（22.60±2.69）%, （35.50±4.38）%, （57.30±4.38）%］, MHF-treated group ［（38.00±3.54）%, （53.00±3.39）%,　（77.10±1.70）%］ and negative control ［（37.95±3.61）%,（19.55±1.06）% and（85.45±1.63）%］（P<0.05）. At 18, 24 and 48 h after induction, the levels of IDO mRNA in rAgB-treated group ［（9.20±0.01）, （29.44±0.02）, （16.48±0.04）］ and MHF-treated group ［（9.67±0.02）, （17.52±0.01）, （16.81±0.01）］ was higher than that of negative control group［（2.46±0.01）, （7.77±0.01）, and（10.56±0.01）］（P<0.01）. And significant  difference was found between rAgB-treated group and MHF-treated group （P<0.05）. At 18, 24 and 48 h after induction, the concentrations of Try were lowest in rAgB-treated group ［（23.65±0.64）, （13.95±1.06）, （19.05±0.64） μmol/L］. At 24 h after induction, Try concentration in negative control group（22.90±0.14） was higher than that of MHF-treated group （20.65±0.34）（P<0.05）.  Conclusion  Under in vitro condition, rAgB and MHF can up-regulate IDO expression. The ability of rAgB to up-regulate IDO activity was stronger than that of MHF at 24 h after induction.

Effect of Long-term Use of Albendazole on Mice Liver

ZHENG Qi，LIU Cong-shan，JIANG Bin，XU Li-li，ZHANG Hao-bing*

2013, 31(3):  7-193-197. 

Asbtract ( )   PDF (1235KB) ( )  

Related Articles | Metrics

 Objective  To observe the change in serum levels of alanine aminotransferase（ALT）, aspartate transaminase （AST）, alkaline phosphatase （ALP）, direct bilirubin （DBL）, indirect bilirubin （IBIL）， albumin （ALB） and globulin（GLB）, and mouse liver ultrastructure during 1-16 weeks of albendazole treatment.   Methods  180 female Kunming mice were divided randomly into albendazole treatment group and negative control group. Each mouse of albendazole treatment group was treated with 136.3 mg/（kg·d） albendazole. The mice in control group were given same amount of physiological saline. After 1, 2, 4, 6, 8, 10, 12, 14 and 16 weeks of treatment, 10 mice from each group were randomly selected, serum samples were collected and analyzed for the above seven liver function indices. Pathological changes of liver were observed by transmission electron microscopy. Linear regression analysis was conducted for the relationship between liver function indices（dependent variable） and pathological scores （independent variable）.  Results  During 1-16 weeks of albendazole treatment, there was no significant difference in serum levels of DBL, IBIL, ALB and GLB between albendazole treatment group and control group. Compared with other treatment period, after 12 weeks of treatment the serum levels of ALT（55.2±23.7）, AST（176.4±49.2） and ALP（141.1±19.4） in albendazole treatment group were higher than that of the control （35.5±8.6, 108.2±21.9, 84.0±24.8） （P<0.05）. After 2, 8, 10, 12 and 14 weeks of treatment, the pathological score of albendazole treatment group was 11.8±4.8, 10.6±4.8, 13.6±3.5, 29.8±10.7, and 5.6±2.5, respectively, which was higher than that of the control （0.8±0.4, 1.2±0.8, 2.4±2.0, 1.2±0.4, 1.4±1.1） （P<0.05）. Among the three liver function indices AST, ALT and ALP, AST was the best fit index for linear regression. The regression formula was Y=-17.616+0.188X.  Conclusion  Long-term treatment with albendazole at a dosage of 136.3 mg/（kg·d） for mice can cause significant elevation of serum levels of ALT, AST and ALP, and result in mild pathological changes in the liver.

Position Analysis of Three Recombinant Proteins of Echinococcus granulosus Protoscolex with Two-dimensional Electrophoresis

ZHU Ming-xing1,2,3, LI Jun-liang1,2, JU Yan1,2，GAO Peng1,2, ZHAO Wei1,2 *

2013, 31(3):  8-198-200,205. 

Asbtract ( )   PDF (283KB) ( )  

Related Articles | Metrics

 Objective  To obtain specific antibodies of the three recombinant antigens obtained previously, rEgZW-5, rEg14-3-3 and rEgP-29, for identifiying the corresponding proteins in two-dimensional electrophoretogram of Echinococcus granulosus protoscolex.  Methods  The distribution of proteins from E. granulosus protoscoleces was judged by SDS-PAGE previously. Two-dimensional electrophoresis was used to separate proteins from E. granulosus protoscoleces, and the result was scanned and analyzed by the PDquest software to get the information about the quantity of proteins as well as their isoelectric point （IP） and relative molecular mass （Mr）. Rabbits were immunized with the 3 recombinant antigens and antibodies were purified from antisera. Western blotting was used to identify the protein  as marker in two-dimensional electrophoretogram of protoscolex.  Results  SDS-PAGE displayed that the proteins separated from Echinococcus granulosus protoscoleces mainly distributed in the Mr region of 18 000-90 000. 240 proteins were obtained by two-dimensional electrophoresis with Mr 15 790-117 050 and IP 4.0-9.5, and 85.8% （206/241） of the proteins showed the IP ranged from 5 to 9. Western blotting showed that the specific antibody of rEg14-3-3 identified the 14-3-3 protein in two-dimensional electrophoretogram of protoscolex with Mr 33 000 and IP 4.86, the specific antibody of rEgZW-5 identified the ZW-5 protein with Mr 23 000 and IP 4.98, and the specific antibody of rEg P-29 identified the P-29 protein with Mr 29 000 and IP 5.65.  Conclusion  The antibodies against the three recombinant proteins from Echinococcus granulosus protoscoleces can identify corresponding proteins in the two-dimensional electrophotoregrams.

The Species and Ecological Distribution of Medical Mollusca in Weifang，Shandong Province

GUO Yun-hai1，LI Na2，HU Ling1，ZHANG Yi1，ZHOU Xiao-nong1 *

2013, 31(3):  9-201-205. 

Asbtract ( )   PDF (1111KB) ( )  

Related Articles | Metrics

Objective  To investigate the species and distribution of mollusca with medical importance in Weifang， Shandong Province.  Methods  Species identification and quantitative statistics analysis was studied based on field-collected snails from the districts of Weifang， Shouguang， Anqiu and Changyi， Shandong Province.  Results  A total of 1 791 medical mollusca specimens were collected， belonging to two Classes, 9 families and 14 species. Some important species were discovered including Parafossarulus striatulus（383）， Alocinma longicornis（34）， Galba pervia （63）， Radix swinhoei（137）， R. auricularia（95）， Physa acuta（677） and Hippeutis cantori（22）. The dominant species were P. acuta and P. striatulus.  Conclusion  There remains a higher diversity of medical mollusca in Weifang, Shandong Province.

Evaluation of the Comprehensive Schistosomiasis Control Measures with Emphasis on Infection Source of Replacing Cattle with Machine

LIU Wei1, CAO Chun-li1 *, CHEN Zhao2, LI Shi-zhu1, TANG Li3, XIAO Ying3, ZHANG Hua-ming4,

2013, 31(3):  10-206-211. 

Asbtract ( )   PDF (1054KB) ( )  

Related Articles | Metrics

Objective  To evaluate the effect of comprehensive measures with an emphasis on schistosomiasis infection source control by replacing cattle with machine.  Methods  In 2011， 2 villages from each of Jingzhou District, Jianli County and Jiangling County, Hubei Province, were selected as intervention group where the comprehensive measures were implemented, while 2 villages from Shishou City served as control with routine control activities. A cluster random sampling was carried out in the 8 villages with more than 300 people in each village were sampled. Stool examination using modified Kato-Katz was applied for identification of the infected persons and hatching test for cattle survey. The systemic sampling was applied for snail survey, fecal specimens from the field were examined by hatching test. Each sample was examined three times. Data were collected for the analysis of control effect between intervention and control groups in 2007 (baseline), 2009 (before implemention of comprehensive measures) and 2011 (post-intervention).  Results  In intervention villages, the overall prevalence in human reduced significantly from 3.6% （135/3 772） in 2007 and 2.0% (63/3 116) in 2009 to 0.9% （21/2 396） in 2011 （χ2=43.411， χ2=11.840， P＜0.05）. Until 2011, there were no cattle in intervention group; the prevalence decreased by 52.6% in huamn and about 100% in cattle from 2010 to 2011. In control group, the infection rate in residents in 2007, 2009 and 2011 was 4.5% （64/1 410）, 2.6% (34/1 294) and 1.8%（24/1 320）, respectively（χ2=16.178， P＜0.05）, and 5.1%（8/158） in 2007, 1.6% (3/187) in 2009 and 1.6%（3/189） in 2011 in cattle, respectively（χ2=3.387， P>0.05）. The infection rate in human and cattle fell by 25.0% and 5.9% from 2010 to 2011, respectively. There was a significant difference in human infection rate between the intervention and control groups after intervention（χ2=6.309， P＜0.05）. No infected snails were detected in intervention and control groups. No positive feces from the field was found in the intervention group,  7.5% positive rate was recorded in the control.  Conclusion  The comprehensive measures focused on infection source control by replacing cattle with machine can effectively control Schistosoma japonicum transmission, with a siginificant decrease of the prevalence in human and cattle.

Preliminary Application of Moving Percentile Method on Surveillance and Early-Warning on Visceral Leishmaniasis in Endemic Areas

FU Qing1,2, LI Shi-zhu1,2, HOU Yan-yan3, ZHANG Song3, LI Jun-jian1, TANG Lin-hua1 *

2013, 31(3):  11-214-217. 

Asbtract ( )   PDF (1018KB) ( )  

Related Articles | Metrics

 Objective  To apply moving percentile method on surveillance and early-warning on visceral leishmaniasis in Kashgar Region and evaluate its effect.  Methods  Incidence data of visceral leishmaniasis in Kashgar Region were collected from the National Web-based Infectious Diseases Report System. Monthly detection was carried out by using moving percentile method. The 50th percentile（P50）, 70th percentile（P70） and 90th percentile（P90） of historical baseline data were calculated for drawing a control chart, and P70 was adopted as the warning threshold to determine whether an epidemic would appear. If the number of cases in one month is higher than the corresponding P70 of historical baseline data, the warning signal will be generated. The sensitivity, specificity and positive predictive value were calculated for the evaluation of early-warning effect.  Results  During the study period, 61.0% cases were reported in the year of 2008 and 2009, the incidence peak was from September to December, accounting for 51.9%, and infants under 3 years old were the population most threatened by visceral leishmaniasis, accounting for 62.7%. A total of 58 detections were performed, and 17 warning signals were generated by the threshold on P70. Among them, the numbers of cases in 9 detections were higher than the corresponding P90 of historical-baseline data. Based on the actually epidemic status of visceral leishmaniasis in study period, according to the threshold on P70, a total of 10 warning signals of 11 epidemics were detected, and the sensitivity of the warning model was 90.9% （10/11）. 7 wrongly signals of 47 non-epidemics were detected, and the specificity was 85.1%（40/47）. 10 of 17 signals were proved to be correct, and the positive predictive value was 58.8%（10/17）.  Conclusion  The moving percentile method can effectively perform surveillance and early-warning on visceral leishmaniasis in Kashgar Region.

Clinical Analysis of 25 Sparganosis Cases

MO Zhi-shuo，LI Xin-hua，LEI Zi-ying，XIE Dong-ying*

2013, 31(3):  12-218-220. 

Asbtract ( )   PDF (999KB) ( )  

Related Articles | Metrics

Objective  To analyse the clinical features of sparganosis patients and improve cognition in the disease.  Methods  The epidemic data, clinical manifestations, auxiliary examinations, diagnosis and treatments of 25 sparganosis patients in the hospital were retrospectively analyzed.  Results  Among the 23 patients with definite epidemicological data , 22 cases were food-borne, one case of contact infection. According to the clinical manifestation，there were 14 cases of central nervous system(CNS) sparganosis， 7 cases of cutaneous sparganosis， 3 cases of visceral sparganosis and 1 case of ocular sparganosis. Eosinophilia in peripheral blood was found in 4 cases including the 3 cases of visceral sparganosis. 22  patients were diagnosed by serologic IgG antibody test. MRI showed positive finding in all CNS sparganosis patients. 11 cases received surgical excision or biopsy, worms were found in 8 cases. 80% of the cases were once misdiagnosed by other disorders. 18 patients were cured and 7 alleviated after treatment.  Conclusion  Sparganosis is mostly a food-borne infection, more involving central nervous system. Serologic test is important for diagnosis, and eosinophilia is uncommon.

Species Identification in 5 Imported Cases Previously Diagnosed as Vivax Malaria by Parasitological and Nested PCR Techniques

YAO Li-nong*，ZHANG Ling-ling，RUAN Wei，CHEN Hua-liang，LU Qiao-yi，YANG Ting-ting

2013, 31(3):  13-221-223,234. 

Asbtract ( )   PDF (1201KB) ( )  

Related Articles | Metrics

Objective  To identify the species of malaria parasites in 5 imported cases previously diagnosed as vivax malaria. Methods  Epidemiological information and blood samples were collected from five patients who returned from Africa and were diagnosed as vivax malaria. The detection was conducted by microscopy, right VIEW rapid malaria test(RDTs) and nested PCR with Plasmodium genus-specific and species-specific primers. The amplified products were sequenced and Blast analysis was performed. Results  Three of the 5 cases had a history of malaria attack. Microscopically, 4 cases were confirmed as Plasmodium ovale infection, 1(case 1) was co-infected with P. vivax and P. ovale. All 5 cases showed negative RDT results. Nested PCR detection revealed that the 5 cases had  a P. ovale-specific fragment(800 bp), while case 1 had a P. vivax-specific fragment(120 bp) concurrently. Blast analysis showed that the amplified sequence of the 5 cases had a high sequence homology(99%) with P. ovale gene for small subunit ribosomal RNA from GenBank, and that of case 1 also shared 99% homology with P. vivax isolate SV5 18S ribosomal RNA gene (GenBank accession number: JQ627157.1).  Conclusion  Among the five cases, four were infected by Plasmodium ovale, and one was co-infected with both P. vivax and P. ovale.

Epidemic Analysis of Echinococcosis in Ganzi Tibetan Autonomous Prefecture of Sichuan Province from 2006 to 2011

XU Gang-rong1, ZHANG Li-jie2, ZENG Guang2 *

2013, 31(3):  14-224-228. 

Asbtract ( )   PDF (1038KB) ( )  

Related Articles | Metrics

Objective  To provide scientific evidence for further improving of the prevention and control strategies for echinococcosis in Ganzi Tibetan Autonomous Prefecture, Sichuan Province, according to the epidemiological characteristics of echinococcosis surveyed in this prefecture.  Methods  Data of echinococcosis cases and surveillance information of Ganzi Tibetan Autonomous Prefecture from 2006 to 2011 were downloaded from the National Infectious Diseases Reporting System,  and statistically analyzed by using SPSS 19.0 and Epi info3.5 software.  Results  A total of 8939 echinococcosis cases was reported during the observed period, the prevalence rate was 818.7/100000, and 88.9% of the patients were herdsmen. Cases distributed in all the 18 counties and counted for 66.8%(217/325) of the townships in Ganzi Prefecture, pasturing and farming-pastoral areas were the highly risk areas. 84.3% cases were reported from Shiqu and Seda Counties, where were the most heavy epidemic regions for echinococcosis prevalence in Sichuan Province. The minimum, maximum and mean age of these cases was 1, 99 and 41 years old. Among them 84.3% were aged from 20 to 60 years old, and the prevalence rate of females was significantly higher than that of males(P＜0.01）. The serological positive rate of children (P＜0.01) and the prevalence rate of livestock in 2011 (P＜0.01) was significantly decreased, comparing with that of in 2007, respectively. There was no statistical difference between the positive rates of dog coproantigen in 2011 and 2007 (P＞0.05).  Conclusion  The prevalence of echinococcosis in Ganzi Tibetan Autonomous Prefecture, Sichuan, was still high, comprehensive prevention and control strategies needed to adopt in the control program in order to reduce the infection of echinococcosis.

Research Progress on Fascioliasis

LIU Qian, CHENG Na, ZHOU Yan, XU Xue-nian*

2013, 31(3):  15-229-234. 

Asbtract ( )   PDF (1091KB) ( )  

Related Articles | Metrics

Fascioliasis is an important zoonosis caused by Fasciola spp. It can cause pathological damages to human liver and gallbladder, as well as economic loss in animal husbandry. Fascioliasis can be easily misdiagnosed with other hepatobiliary diseases. The appearance of resistance to triclabendazole is an issue problem for fascioliasis control. Therefore, research for better diagnostic methods, effective drugs and vaccines become to the focus of fascioliasis control. This article summarizes the progress on epidemiological status, diagnostic method, therapy, drug resistance, vaccine and omics of fascioliasis.

Research Progress on Diagnostic Methods for Babesia microti Infection

SUN Jia-hui1, HAN Jian-ping2, FENG Zheng1, HU Wei1，3 *

2013, 31(3):  16-235-237,241. 

Asbtract ( )   PDF (242KB) ( )  

Related Articles | Metrics

Human babesiosis, a malaria-like zoonosis transmitted by the tick, is mainly distributed in Europe, USA and some Asian countries. There are various kinds of diagnostic methods for babesiosis caused by Babesia microti, but many of them are still in the preliminary stage. This article reviewes the main diagnostic techniques and the existing problems.

Pathogen Associated Molecular Patterns of Parasite

YANG Qing-li1 *, SHEN Ji-qing2

2013, 31(3):  17-238-241. 

Asbtract ( )   PDF (1007KB) ( )  

Related Articles | Metrics

With the research progress of classical pathogen associated molecular patterns（PAMPs） from pathogenic microbes, the presence of the parasite PAMPs has been confirmed. The parasite PAMPs show some differences from classical PAMPs in molecular structures, receptor binding ways, intracellular signal transduction pathways, and induced effects. This review focuses on the issues of parasite PAMPs.

Extraction and Morphological Observation of  Oncomelania hupensis Haemocytes

XU Yong1，HUANG Chun-lan2，ZHOU Shu-lin2，LIU hui3 *

2013, 31(3):  18-211-213. 

Asbtract ( )   PDF (1258KB) ( )  

Related Articles | Metrics

Haemocytes were collected from Oncomelania hupensis snails by using tissue disruption and filtration method, stained by Giemsa and methylene blue, respectively, and observed under microscope. Number of haemocytes from one snail was counted. Out of 54 haemocytes, 3 types of cells were found: big round cells with particles, small round cells with oval nuclei and spindle cells with oblong nuclei. The diameter of big round cells with particles and small round cells with oval nuclei was （21.59-31.97） and （13.24-20.77） μm, respectively. Spindle cells with oblong nuclei was about （17.60-25.47） μm×（27.19-30.25） μm. The nucleocytoplasmic ratio of the above three type cells was 0.38, 0.44 and 0.38, and occupied 35.95% （19/54）, 12.42% （28/54） and 51.63% （7/54）, respectively. About 194 600 haemocytes were filtered from one single snail. It means that this filtration method is an effective one to extract haemocytes from O. hupensis.

Report on 16 Cases of Small Intestine Ascariasis Diagnosed by Capsule Endoscopy

WANG Pu1，LI Rong-zhi2，HUANG Zhi-yin1，TANG Cheng-wei1 *

2013, 31(3):  19-242-243. 

Asbtract ( )   PDF (1040KB) ( )  

Related Articles | Metrics

The clinical data and capsule endoscopy image of 16 adult patients with small intestine ascariasis were reviewed and analyzed retrospectively from June 2006 to June 2012 in West China Hospital. Among the 16 patients， 15 cases manifested as gastrointestinal bleeding, 15 cases showed anemia （3 severe， 10 moderate， and 2 mild）, 2 had hypoalbuminemia, 1 had peripheral blood eosinophilia. All the cases were found to be fecal occult blood positive, but no Ascaris eggs found in the feces. Capsule endoscopy showed they were infected with Ascaris worms. The worms were found in the proximal small intestine in 14 patients and 2 in the distal intestine. Mucosal erythema and erosions around the worm were observed in 3 cases, and 7 cases were found with active bleeding or old haemorrhage in small intestine.  

Effect of Transposase on the Transposition Activity of piggyBac Transposon Transfected into Toxoplasma gondii

SONG Xin-shuai1，WEI Feng1 *，ZHANG Ying-guang1，CAO Li-li2，LIU Quan2

2013, 31(3):  20-244-封三. 

Asbtract ( )   PDF (1031KB) ( )  

Related Articles | Metrics

To determine the transfection efficiency about PBase to piggyBac transposon in transfecting to Toxoplasma gondii, T. gondii RH strain tachyzoites were transfected with plasmid PB-Toxo-RFP which was expressed piggyBac transposon with a red fluorescent protein and Toxo-PBase plasmid which is a transposable enzyme. T. gondii tachyzoites were transfected with PB-Toxo-RFP plasmid alone as control group. The expression of red fluorescent protein was detected by flow cytometry at 24 h after transfection. The transposition efficiency in PB-Toxo-RFP+Toxo-PBase group and PB-Toxo-RFP group was 73% and 43%, respecitvely（P<0.01）. It suggests that the PBase transposase can improve the transfection efficiency of piggyBac transposon in T. gondii tachyzoites.