Diagnostic efficacy of indirect haemagglutination assay for detection of Schistosoma japonicum infections among boatmen and fishermen in the Dongting Lake region / 中国血吸虫病防治杂志

OBJECTIVE@#To evaluate the diagnostic efficacy of indirect haemagglutination assay (IHA) for detection of Schistosoma japonicum infections among boatmen and fishermen in Dongting Lake region, so as to provide insights into improving the schistosomiasis surveillance program among boatmen and fishermen.@*METHODS@#The boatmen and fishermen were detected for S. japonicum infections using IHA and Kato-Katz technique or miracidium hatching test nylon gauze simultaneously at schistosomiasis testing sites in the anchor sites for boatmen and fishermen in the Dongting Lake region during the period from 2014 to 2016, and using IHA for serological screening followed by parasitological testing of seropositives during the period from 2017 to 2019. The sensitivity and specificity of IHA were evaluated for detection of S. japonicum infections among boatmen and fishermen, with the 2014-2016 parasitological testing results as a gold standard. In addition, the seroprevalence of S. japonicum infections was compared among boatmen and fishermen with different characteristics and among years.@*RESULTS@#A total of 306 schistosomiasis testing sites were assigned for boatmen and fishermen, and a total of 143 360 person-time boatmen and fishermen were tested for S. japonicum infections in the Dongting Lake region from 2014 to 2019. The sensitivity and specificity of IHA were 69.9%, 97.3% and 96.1% (χ2 = 74.6, P < 0.05), and 70.9%, 74.5% and 71.9% for detection of S. japonicum infections from 2014 to 2016 (χ2 = 29.4, P < 0.05), respectively. The seroprevalence of S. japonicum infections reduced from 30.3% in 2014 to 1.8% in 2019 among boatmen and fishermen, appearing an overall tendency towards a decline (Z = 1 552.4, P < 0.05). In addition, male, individuals at ages of 45 to 60 years, full-time boatmen and fishermen were more likely to be seropositive for S. japonicum infections (all P values < 0.05).@*CONCLUSIONS@#The seroprevalence of S. japonicum infections appeared a tendency towards a decline among boatmen and fishermen in the Dongting Lake region year by year from 2014 to 2019. IHA presented a high efficacy for screening of S. japonicum infections among boatmen and fishermen in the Dongting Lake region.

Soluble egg antigen of Schistosoma japonicum induces macrophage apoptosis in mice / 中国血吸虫病防治杂志

OBJECTIVE@#To investigate the dynamic changes of macrophage numbers and apoptosis during Schistosoma japonicum infection, and to investigate the possible mechanisms of macrophage apoptosis induced by S. japonicum soluble egg antigen (SEA).@*METHODS@#C57BL/6 mice at ages of 6~8 weeks were randomly divided into 4 groups, including three experimental groups and a normal control group. Each mouse in the experimental groups was infected with (12 ± 1) cercariae of S. japonicum via the abdominal skin, and all mice in an experimental group were sacrificed 3, 5, 8 weeks post-infection, respectively, while mice in the control group were not infected with S. japonicum cercariae and sacrificed on the day of S. japonicum infection in the experimental group. Mouse liver specimens and peritoneal exudation cells were sampled in each group, and the dynamic changes of macrophage numbers and apoptosis were detected. Mouse peritoneal macrophages were isolated, purified and treated with S. japonicum SEA, PBS and ovalbumin (OVA) in vitro, and the macrophage apoptosis was detected using flow cytometry. The mRNA and protein expression of BCL-2 protein family members were determined in macrophages using real-time quantitative PCR (qP-CR) and Western blotting assays, and the activation of caspase 3 was determined using flow cytometry and Western blotting. In addition, macrophages were in vitro treated with S. japonicum SEA in presence of a caspase inhibitor, H2O2 or N-acetyl-L-cysteine, and the apoptosis of macrophages was detected using flow cytometry.@*RESULTS@#The total macrophage numbers continued to increase in mouse liver [(0.873 ± 0.106) × 106, (2.737 ± 0.460) × 106 and (3.107 ± 0.367) × 106 cells, respectively; F = 81.900, P < 0.01] and peritoneal specimens [(5.282 ± 1.136) × 105, (7.500 ± 1.200) × 105 and (12.800 ± 0.800) × 105 cells, respectively; F = 55.720, P < 0.01] 3, 5 and 8 weeks post-infection with S. japonicum, and the numbers of apoptotic macrophages also continued to increase in mouse liver [(0.092 ± 0.018) × 106, (0.186 ± 0.025) × 106 and (0.173 ± 0.0270) × 106 cells; F = 57.780, P < 0.01] and peritoneal specimens [(0.335 ± 0.022) × 105, (0.771 ± 0.099) × 105 and (1.094 ± 0.051) × 105 cells; F = 49.460, P < 0.01] 3, 5 and 8 weeks post-infection with S. japonicum. The apoptotic rate of SEA-treated macrophages [(24.330 ± 0.784)%] was significantly higher than that of PBS-[(18.500 ± 1.077)%] and OVA-treated macrophages [(18.900 ± 1.350)%] (both P values < 0.01). There were no significant differences in the mRNA or protein expression of Bcl-2 [Bcl - 2 mRNA expression: (1.662 ± 0.943) vs. (1.000 ± 0.000), t = 1.215, P > 0.05; BCL protein expression: (0.068 ± 0.004) vs. (0.070 ± 0.005), t = 0.699, P > 0.05], Bax [Bax mRNA expression: (0.711 ± 0.200) vs. (1.000 ± 0.000), t = 2.507, P > 0.05; BAX protein expression: (0.089 ± 0.005) vs. (0.097 ± 0.003), t = 2.232, P > 0.05] and Bak [Bak mRNA expression: (1.255 ± 0.049) vs. (1.00 ± 0.00), t = 0.897, P > 0.05; BAK protein expression: (0.439 ± 0.048) vs. (0.571 ± 0.091), t = 2.231, P > 0.05] between in SEA- and PBS-treated macrophages. S. japonicum SEA induced macrophage apoptosis in the presence of a caspase inhibitor (F = 0.411, P > 0.05); however, SEA failed to induce macrophage apoptosis in the presence of H2O2 or NAC (F = 11.880 and 9.897, both P values < 0.05).@*CONCLUSIONS@#S. japonicum SEA may induce macrophage apoptosis through promoting reactive oxygen species expression during S. japonicum infections in mice.

Plasma D-dimer Can Effectively Predict the Prospective Occurrence of Ascites in Advanced Schistosomiasis Japonica Patients

China still has more than 30,000 patients of advanced schistosomiasis while new cases being reported consistently. D-dimer is a fibrin degradation product. As ascites being the dominating symptom in advanced schistosomiasis, the present study aimed to explore a prediction model of ascites with D-dimer and other clinical easy-achievable indicators. A case-control study nested in a prospective cohort was conducted in schistosomiasis-endemic area of southern China. A total of 291 patients of advanced schistosomiasis were first investigated in 2013 and further followed in 2014. Information on clinical history, physical examination, and abdominal ultrasonography, including the symptom of ascites was repeatedly collected. Result showed 44 patients having ascites. Most of the patients' ascites were confined in the kidney area with median area of 20 mm². The level of plasma D-dimer and pertinent liver function indicators were measured at the initial investigation in 2013. Compared with those without ascites, cases with ascites had significantly higher levels of D-dimer (0.71±2.44 μg/L vs 0.48±2.12 μg/L, P=0.005), as well ALB (44.5 vs 46.2, g/L) and Type IV collagen (50.04 vs 44.50 μg/L). Receiver operating characteristic curve analyses indicated a moderate predictive value of D-dimer by its own area under curve (AUC) of 0.64 (95% CI: 0.54–0.73) and the cutoff value as 0.81 μg/L. Dichotomized by the cutoff level, D-dimer along with other categorical variables generated a prediction model with AUC of 0.76 (95% CI: 0.68–0.89). Risks of patients with specific characteristics in the prediction model were summarized. Our study suggests that the plasma D-dimer level is a reliable predictor for incident ascites in advanced schistosomiasis japonica patients.

Expression profiling and immunofluorescence localization of the major egg antigen p40 of Schistosoma japonicum in the liver of infected New Zealand white rabbits / 南方医科大学学报

<p><b>OBJECTIVE</b>To examine the expression profile and immunofluorescence localization of the major egg antigen p40 of Schistosoma japonicum (Sjp40) during granuloma formation in the liver of infected New Zealand white rabbits.</p><p><b>METHODS</b>New Zealand white rabbits were infected with S. japonicum cercariae, and the livers were harvested at 29 and 45 days post-infection (dpi). The total RNA of the liver tissues was extracted for expression profiling of Sjp40 by quantitative reverse transcription-PCR (qRT-PCR) with GAPDH of S. japonicum as the endogenous reference gene. The expression of Sjp40 in the liver were detected by Western blotting using anti-Sjp40 monoclonal antibody (mAb) 9G7 or anti-Toxoplasma gondii tSAG1 mAb Y3A8 (control) as the primary antibody. Paraffin sections of the liver were prepared for observing egg granuloma formation using HE staining and for indirect immunofluorescence assay of Sjp40 location in the trapped eggs and egg granulomas.</p><p><b>RESULTS</b>The level of Sjp40 mRNA in the eggs trapped in rabbit livers was significantly higher at 45 dpi than that at 29 dpi (P<0.05), and Western blotting confirmed the presence of Sjp40 protein in the rabbit livers at both 29 and 45 dpi. Immunofluorescence assay demonstrated localized expression of Sjp40 in the immature eggs in the rabbit liver at 29 dpi, but at 45 dpi fluorescence was detected in clusters of mature eggs containing miracidium and in the surrounding egg granulomas.</p><p><b>CONCLUSIONS</b>The transcriptional levels of Sjp40 significantly increased with the maturation of eggs trapped in the rabbit livers. Sjp40 protein spread from the eggs to the surrounding egg granuloma at 45 dpi when acute liver granulomatous lesions occur, suggesting that Sjp40 plays a key role in egg granulomas formation in the livers of infected New Zealand white rabbits.</p>

Reinfection of Schistosoma japonicum and related risk factors in Chinese: Meta-analysis / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the dynamics of the reinfection of Schistosoma japonicum and related risk factors among the people in schistosomiasis endemic areas in China.</p><p><b>METHODS</b>Literature retrieval was conducted by using databases of PubMed, CNKI,VIP and Wanfang to collected all the data about the human re-infection of Schistosoma japonicum and related risk factors in the endemic areas in China. And a Mata-analysis was conducted on the literatures met the inclusion standards.</p><p><b>RESULTS</b>Eighteen studies involving 12 604 people for infection survey and 3 128 people for re-infection survey were included in the analysis. The overall infection rate was 20.8%, and the overall re-infection rate was 21.0% . The difference had no statistical significance (Z = 1.12, P = 0.26). The re-infection related factors included baseline infection intensity (OR = 3.58, 95% CI: 1.56-8.22); the index of contaminated water OR = 2.37, 95% CI: 1.08-5.22); distance from house to river-side (OR = 1.72, 95% CI: 0.41-7.30) and age (OR = 0.48, 95% CI: 0.19-1.23).</p><p><b>CONCLUSION</b>The baseline infection intensity, the index of contaminated water and distance from house to river-side were the risk factors related to the re-infection of Schistosoma japonicum and age was a protective factor.</p>

Changes in splenocyte proliferation, subsets and cytokine production in mice immunized with recombinant vaccine Bifidobacterium bifidum (pGEX-Sj32) of Schistosoma japonicum / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the dynamic changes of immune responses of splenocytes in mice immunized with recombinant vaccine Bifidobacterium bifidum (pGEX-Sj32) of Schistosoma japonicum and investigate the immunological mechanism of the vaccine.</p><p><b>METHODS</b>Eighty-eight BALB/c mice were randomized for immunization with 10⁶ CFU recombinant vaccine orally or with 10⁵ CFU recombinant vaccine intranasally. Four mice were selected from each group every two weeks to test the responses of the splenocytes to stimulations with SjAWA or ConA. MTT assay and flow cytometry were used to assess splenocyte proliferation and the distribution of CD4⁺ and CD8⁺ T cells, respectively; the levels of interleukin-10 (IL-10), IL-12 and tumor necrosis factor-α (TNF-α) in the cell culture supernatant were detected by ELISA.</p><p><b>RESULTS</b>Regardless of the stimulations, the splencytes showed significantly enhanced proliferation in weeks 2-16 in oral administration group and in weeks 2-18 in intranasal group (P<0.01). CD4⁺ subsets in both two groups increased obviously in weeks 2-12 (P<0.01) but CD8⁺ subsets remained stable. In oral administration group, the levels of TNF-α, IL-10 and IL-12 increased in weeks 2-14, 2-18 and 2-14, and peaked at week 8, 10 and 6, respectively; in intranasal group, the cytokines increased in weeks 2-14, 2-18 and 2-18, and peaked at week 8, 10 and 8, respectively.</p><p><b>CONCLUSION</b>The recombinant vaccine rBb (pGEX-Sj32) can induce effective immune responses in mice.</p>

Cloning, expression of gene SjOST48 from Schistosoma japonicum and evaluation of the immunoprotective efficacy of rSjOST48 in mice / 生物工程学报

To identify SJCHGC01743 gene of Schistosoma japonicum and evaluate the potential of the recombinant protein as a new vaccine candidate for schistosomiasis, polymerase chain reaction (PCR) technique was used to amplify the cDNA of the gene and real-time RT-PCR was used to analyze the transcription profiles of SJCHGC01743 at different development stages. Recombinant plasmid was successfully constructed and transformed into competent Escherichia coli BL21 (DE3). Then the recombinant protein was expressed, purified and emulsified with ISA206 adjuvant to immunize BALB/c mice for three times. The immunogenicity was confirmed by Western blotting and tissue localization was detected by indirect immunofluorescent assay. The specific antibody level was detected by ELISA. The immunoprotection of rSjOST48 was evaluated by the reduction in worm and egg counts in mice. A cDNA with 1 248 nucleotides was isolated from 28-day-old schistosomes cDNAs by PCR. Sequence analysis revealed that SJCHGC01743 was a 48-kDa subunit of the oligosaccharyltransferase complex (OST48) and named as SjOST48. Real-time PCR analysis indicated that this gene was expressed in all investigated stages and had the highest expression level in 28 d worms, the level of gene transcription in female worms was significantly higher than that of male worms. Then recombinant plasmid pET28a(+)-SjOST48 was successfully constructed and expressed in E. coli BL21 (DE3). Western blotting analysis showed that rSjOST48 had good immunogenicity. Indirect immunofluorescent analysis revealed that SjOST48 was mainly distributed on the tegument of the worms. The result of ELISA indicated that the rSjOST48 vaccinated group could induce a significant increase in the level of specific IgG, IgG1 and IgG2a. An immunoprotection experiment showed that the vaccination of rSjOST48 in mice induced 32.62% (P < 0.05) reduction in the numbers of worms and 57.61% (P < 0.01) in eggs in liver, compared with that of the control group. This study provides the foundation for proceeding further research on the biological function of SjOST48 and screening new vaccine candidates for schistosomiasis.

Cloning, expression and protective efficacy evaluation of radiation sensitive protein 23 (RAD23) from Schistosoma japonicum / 生物工程学报

Radiation sensitive protein 23 (RAD23) is a nucleotide excision repair (NER) protein that plays an important role in Ubiquitin-proteasome pathway (UPP). Schistosoma japonicum radiation sensitive protein23 (SjRAD23) cDNA sequences were amplified by PCR and cloned into pET28a (+) vector to construct recombinant expression plasmid pET28a(+)-SjRAD23. The recombinant protein was expressed as both inclusion bodies and the supernatant in Escherichia coli BL21 (DE3) cell. Immunofluorescence observation shows that SjRAD23 was mainly distributed on the tegument surface of the worms. ELISA assay reveals that specific IgG, IgG1 and IgG2a antibodies could be detected in the sera of rSjRAD23 immunized mice. Western blotting analysis shows that the recombinant SjRAD23 could be recognized by serum specific to soluble adult worm antigen of S. japonicum. BALB/c mice vaccinated with rSjRAD23 combined with 206 adjuvant revealed 35.94% worm reduction and 40.59% liver egg reduction when compared with that of the adjuvant control

Risk evaluation of schistosomiasis japonica input to potential endemic areas in Anhui province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the impact of water transfer project from the Yangtze River to the Huaihe River on schistosomiasis transmission, and to evaluate the risk of the disease input to the potential endemic area in Anhui Province, namely the Chaohu Lake region.</p><p><b>METHODS</b>From 2008 to 2012, 1 fixed and 3 mobile surveillance sites in the Chaohu Lake area were selected, and the schistosomiasis infection situation of 615 local residents in the fix surveillance site was investigated in autumn of 2008 and 2012, while the schistosomiasis infection situation of 1603 mobile population in the 3 mobile surveillance sites were investigated in autumn of 2008 to 2012. All people were screened by indirect hemagglutination assay (IHA), and the positive ones were then examined by sedimentation method. 303 local livestock and livestock from schistosomiasis endemic areas were examined by stool hatching method in autumn of 2008 to 2012. From 2008 to 2012, the distribution of Oncomelania snails was investigated in risk areas and suspicious areas, and the snail spreading pattern was conducted through salvaging floaters in rivers connected with the Yangtze River. In addition, the Oncomelania snails were raised in the cages on the beaches of the Chaohu Lake, a control area, from 2007 to 2010, and their survival and reproduction capacity was observed.</p><p><b>RESULTS</b>In 2008 and 2012, 301 and 314 local residents were detected by IHA, but there were no positive found. From 2008 to 2012, a total of 1603 mobile population were examined by IHA, and the positive rate of antibody was 3.1% (49/1603); 75 individuals were examined by sedimentation method, and the positive rate was 36.00% (27/75). A total of 303 livestock were examined by stool hatching method, but no one showed positive. A total of 1630 km(2) in risk areas and 3551 km(2) in suspicious areas were surveyed, but there were no Oncomelania snails found. A total of 457.6 kg floating debris were investigated, and 11 Oncomelania snails were found. From 2007 to 2010, the survival rate of Oncomelania snails in two trail areas in the Chaohu Lake and in the control area was 88% (86/98), 51% (45/89), 30% (25/71), 24% (20/84) and 92% (85/92), 54% (50/92), 23% (12/52), 17% (13/79) and 96% (85/89), 52% (44/85), 26% (18/69), 18% (14/76), respectively, there were no statistical significance between the trial areas and the control area (χ1(2) = 3.78, P > 0.01; χ2(2) = 0.27, P > 0.01; χ3(2) = 2.51, P > 0.01; χ4(2) = 1.50, P > 0.01), and filial generation snails were found in each observation area from 2008 to 2010, the number was 156-312.</p><p><b>CONCLUSION</b>The imported infectious sources of schistosomiasis have been found in the Chaohu Lake region, the possibility of imported exogenous Oncomelania snails spreading into the Lake and surviving and reproducing there is high. The risk of schistosomiasis input to the potential endemic area in Anhui Province is predicted to be high.</p>

DNA prime followed by protein boost enhances the protective efficacy against Schistosoma japonicum infection in mice / 生物工程学报

Schistosomiasis japonica is an endemic, zoonotic disease of major public health importance in China. Vaccination is needed as a complementary approach to the ongoing control programs. In the present study, we determined if the efficacies of DNA vaccine encoding the SjGST and Sj32 asparaginyl endopeptidase protein could be enhanced by boosting with SjGST-32 protein vaccines. Mice were inoculated with a VR1012-SjGST-32 DNA vaccine followed by boosting with rSjGST-32 at 0, 14 and 28 d. Two weeks after the final boost, mice were challenged percutaneously with cercariae. On day 45 following the challenge, all mice were sacrificed and the numbers of recovered worms and hepatic eggs were counted. Moreover, we analyzed the immune response among various vaccination groups. The results showed that DNA vaccine efficacy was enhanced when mice were boosted with protein vaccine. Adult worm and liver egg burdens were reduced 42.3% and 59.6%, respectively. We further found that DNA vaccine followed by boosting with protein significantly increased the IgG titer and T cell proliferation over those seen in mice vaccinated solely with DNA vaccines. Furthermore, the higher level of IFN-gamma expression in the splenetic CD4+ T cell showed that DNA prime-Protein boosting vaccine induced CD4+ Th1-type responses. Thus, DNA vaccine efficacy was significantly enhanced via boosting protein vaccine which might provide a basis for rational application of the Schistosoma vaccine.

Protective effect of SjC23-Hsp70 DNA vaccine and interleukin-12 on Schistosoma japonicum infection in water buffalos / 中南大学学报(医学版)

OBJECTIVE@#To determine the immune-protective effect of Japan Schistosoma (Chinese mainland strain) 23 kD membrane protein-heat shock protein (SjC23-Hsp70) DNA vaccine plus adjuvantinduced interleukin-12 (IL-12) plasmid DNA on Schistosoma japonicum infection in water buffalos.@*METHODS@#Forty-five health water buffalos (8-10 months old) in non-endemic area of schistosomiasis were randomly assigned into group A (SjC23-Hsp70+IL-12, 300 μg), group B (SjC23+IL-12, 300 μg) and group C (pVAX+IL-12, 300 μg), 15 in each group. Each buffalo was immuned by shoulder intramuscular injection for 3 times, at an interval of 28 days. Twenty-eight days after the last immunization, each buffalo was infected with 1000 Japan cercariae of Schistosoma. Fecal examinations were conducted 2 days and 1 day before the perfusion, and on the day of perfusion. The number of hatching miracidia and eggs per gram feces was recorded. Fifty-six days after the infection, the buffalos were sacrificed and perfused via the descending aorta. The recovered adult worms and eggs in the liver tissue were counted.@*RESULTS@#We compared group A and B with group C: the estrogen reduction rate was 45.7% and 26.61%; bug reduction rate was 44.51% and 25.84%; the fecal egg reduction rate was 41.1% and 31.63%; the miracidium reduction rate was 48.11% and 38.07%; and the liver egg reduction rate was 43.39% and 31.95%. The above rates in group A were higher than those in group B (P<0.05).@*CONCLUSION@#SjC23-Hsp70 DNA vaccine combined with IL-12 may have a significant immunoprotective effect on buffalos.

Immunodiagnostic efficacy of detection of Schistosoma japonicum human infections in China: a meta analysis

OBJECTIVE@#To assess the diagnostic efficacy of the currently most widely used indirect hemagglutination assay (IHA) and enzyme-linked immunosorbent assay (ELISA) for detection of Schistosoma japonicum human infections.@*METHODS@#A comprehensive search was undertaken from China National Knowledge Infrastructure, Wanfang Database, VIP Database, PubMed, Cochrane Library, Science Citation Index Expanded, Proquest, and the inclusion and exclusion criteria were strictly settled. The funnel plot was used to assess the publication bias, Cochran's Q test was employed to measure the homogeneity between studies, a summary receiver operating characteristic (SROC) curve was used to compare the diagnostic accuracy between the IHA and ELISA qualitatively by means of the Weighted Least Square method, the Ordinary Least Square method and the Robust regression method, and the diagnostic odds ratio (DOR) was drawn to compare the accuracy quantitatively.@*RESULTS@#Out of 785 publications, 19 papers were eventually selected for analysis. Literature quality assessment indicated that minor publication bias existed in studies pertaining IHA test, but no bias was found in literatures regarding ELISA test. The heterogeneity test showed a heterogeneity between studies was present (χ(2)=466.07 and 34.67, both P values<0.0001). The areas under the SROC curves of IHA were all higher than that of ELISA test using the three methods (Weighted Least Square method: 0.766 vs. 0.695, Ordinary Least Square method: 0.826 vs. 0.741, Robust regression: 0.815 vs. 0.715). The TPR* values for IHA and ELISA were 0.710, 0.759, 0.749, and 0.650, 0.686 and 0.666, respectively, and OR values were 5.997, 9.937, 8.893, and 3.432, 4.784 and 3.959, respectively. The DOR of IHA was 9.41 (95% CI: 4.88-18.18), and 4.78 (95% CI: 3.21-7.13) for ELISA.@*CONCLUSIONS@#All above results revealed that the diagnostic performance of IHA is better than that of ELISA. However, taking into account their unsatisfactory diagnostic value in areas with low infection intensity, a search for a better diagnostic test that can be applied in field situations in China should be given high priority.

Effects of AIBL on Oncomelania hupensis, the intermediate snail host of Schistosoma japonicum: an enzyme histochemical study

OBJECTIVE@#To explore the effect of AIBL on Oncomelania hupensis, the intermediate snail host of Schistosoma japonicum.@*METHODS@#The enzyme histochemical profiles of cholinesterase, cytochrome oxidase, lactate dehydrogenase, nitric oxide synthase, and succinate dehydrogenase in the soft tissues of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum, were analyzed before and after treatment with the active ingredient of Buddleia lindleyana (AIBL), a potent and safe plant molluscicide.@*RESULTS@#Treatment with AIBL induced a notable decrease in the activities of the five enzymes (P<0.01).@*CONCLUSIONS@#The results indicate that AIBL impairs the activities of the enzymes, thereby influencing the transfer of neurotransmitter and energy supply in Oncomelania hupensis and ultimately harming their various physiological functions, which are considered to cause death of the species.

Bioinformatics analysis of the structure and linear B-cell epitopes of aquaporin-3 from Schistosoma japonicum

OBJECTIVE@#To analyze the structure of aquaporins-3(AQP-3) from Schistosoma japonicum(SJAQP-3) using bioinformatical methods, and to provid of references for vaccine targets research.@*METHODS@#Protparam, BepiPred, TMHMM Server, MLRC, Geno3d, DNA star software packages were used to predict the physical and chemical properties, hydrophilicity plot, flexibility regions, antigenic index, surface probability plot, secondary structure, and tertiary structure of amino acid sequence of SJAQP-3.@*RESULTS@#SJAQP-3 had six transmembrane regions and two half-spanning helices that form a central channel. The half-spanning helices fold into the centre of the channel. Either of the half-spanning helix had a conserved motif of NPA common to all aquaporins. Predicted linear B-Cell epitopes were most likely at the N-terminal amino acid residues of 5aa-7aa, 59aa-62aa, 225aa-230aa, 282aa -288aa, 294aa -298aa and 305aa -307aa area. 59aa- 62aa, 225aa-230aa located outside the membrane, the others located inside the cell.@*CONCLUSIONS@#SJAQP-3 is a integral membrane protein in Schistosoma japonicum tegument. There are six potential epitopes in SJAQP-3. It might be a potential molecular target for the development of vaccines.

Schistosomal glomerulopathy and changes in the distribution of histological patterns of glomerular diseases in Bahia, Brazil

Distinct patterns of glomerular lesions, including membranoproliferative glomerulonephritis and focal segmental glomerulosclerosis, are associated with infection by Schistosoma mansoni or Schistosoma japonicum. Evidence suggests that immune complex deposition is the main mechanism underlying the different forms of schistosomal glomerulonephritis and that immune complex deposition may be intensified by portal hypertension. The relationship between focal segmental glomerulosclerosis and schistosomiasis remains poorly understood. A clinicopathologic classification of schistosomal glomerulopathies was proposed in 1992 by the African Association of Nephrology. In Brazil, mass treatment with oral medications has led to a decrease in the occurrence of schistosomal glomerulopathy. In a survey of renal biopsies performed in Salvador, Brazil, from 2003-2009, only 24 (4 percent) patients were identified as positive for S. mansoni infection. Among these patients, only one had the hepatosplenic form of the disease. Focal segmental glomerulosclerosis was found in seven patients and membranoproliferative glomerulonephritis was found in four patients. Although retrospective studies on the prevalence of renal diseases based on kidney biopsies may be influenced by many patient selection biases, a change in the distribution of glomerulopathies associated with nephrotic syndrome was observed along with a decline in the occurrence of severe forms of schistosomiasis.

Numerical evaluation of new control method for schistosomiasis / 生物医学工程学杂志

Schistosomiasis is a kind of common disease around the riverside or lakeside areas, especially popular in rural areas, and causes huge economic loss. Based on existing schistosomiasis dynamic models and data, a new method of working out coefficients, and an improved model were provided in our study. The improved model can be applied to the study of the characteristics of transmission of schistosomiasis, and the effect of new control methods for schistosomiasis was evaluated.

Infection of Schistosomiasis japanicum is likely to enhance proliferation and migration of human breast cancer cells: mechanism of action of differential expression of MMP2 and MMP9

<p><b>OBJECTIVE</b>To study whether the infection of Schistosomiasis japanicum (S. japanicum) is related to enhanced proliferation and migration of cancer cells, and the molecular mechanism pertains to cancer cell metastasis in human host.</p><p><b>METHODS</b>The gene of S. japanicum glutathione transferase (sjGST) cloned from S. japanicum was expressed, purified and applied in a series of assays to explore the effect of sjGST on proliferation and migration of MDA-MB-435S, and the expression of MMP2 and MMP9. Immunofluorescence assay for the binding of sjGST to MDA-MB-435S was also carried out.</p><p><b>RESULTS</b>Results showed that sjGST enhanced proliferation and migration in human breast cancer cell MDA-MB-435S signifycantly at 50-200 nM, but did not enhance them in human lung cancer cell A549. Immunofluorescence assay for the binding of sjGST to MDA-MB-435S and A549 showed that GST was readily bound to the breast cancer cells, but showed almost no binding to human lung cancer cells. The assays for gelatinase activity showed that both MMP2 and MMP9 activities were increased significantly in the presence of sjGST (50-200 nM) in MDA-MB-435S, but they were not significant in A549.</p><p><b>CONCLUSIONS</b>Our current results show strongly that S. japanicum GST binds to MDA-MB-435S probably via its receptor, and enhances proliferation and migration of the cancer cells by up-regulatory expression of MMP2 and MMP9.</p>

Therapeutic effect of Haobieyangyinruanjianfang on the mouse liver fibrosis caused by schistosomiasis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore therapeutic effect of Haobieyangyinruanjianfang (HBYYRJ) on mouse liver fibrosis by schistosomiasis.</p><p><b>METHODS</b>Mice except for normal control were infected with Japanese schistosome cercarias, after 12 weeks, infected mice were divided into 7 groups: low HBYYRJ group, middle HBYYRJ group, high HBYYRJ group, Fufangbiejiaruangan tablet (FFBJRG) group, colchicine group, 3 months infection group and 6 months infection group. Hepatic fibrosis was found in 3 months infection group. Liver hydroxyproline (Hyp) was determined, matrix metalloproteinase-2 and 9 (MMP-2, MMP-9) were detected with gelatin zymography, serum hyaluronic acid (HA) and precollagen III (PC-III) were detected using RIA.</p><p><b>RESULTS</b>HBYYRJ obviously reduced hepatic fibrosis (probability value less than 0.01). Collagen and HA in 3 months infection group and 6 months infection group were higher than that in normal group (probability value less than 0.01), collagen in high and middle HBYYRJ groups and HA in middle and low HBYYRJ groups were lower than that in 6 months infection group (P less than 0.01, probability value less than 0.05). The expression of MMP-9 and MMP-2 in 3 months infection group and 6 months infection group was higher than that in normal group (probability value less than 0.01), The expression of MMP-9 in three HBYYRJ groups and the expression of MMP-2 in high HBYYRJ group were lower than that in 6 months infection group (probability value less than 0.05).</p><p><b>CONCLUSION</b>HBYYRJ can reduce liver fibrosis caused by schistosomiasis.</p>

Study on an intervention model of "schools without infected students with schistosoma japonica" in heavy endemic areas / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study an intervention model of "schools without infected students with schistosoma japonica", to control and prevent students from schistosoma infection.</p><p><b>METHODS</b>Twelve primary schools of four heavy endemic counties (districts) with schistosomiasis in the Poyang Lake areas were selected as the study fields, of which, ten schools were the experimental groups, and the other two schools were the control groups by cluster random sampling. All enrolment students were the target population. The baseline survey was carried out in 2005, and an intervention model, "information dissemination + behavior participation + behavior encouragement", was applied in the experiment groups in 2006 - 2008, then the effect of intervention was assessed.</p><p><b>RESULTS</b>Before intervention (2005), the anti-schistosomiasis knowledge awareness rate of experimental and control groups were 14.75% (324/2196) and 16.58% (91/549), and the different was not significant (χ(2) = 1.14, P > 0.05); the rate of accurate attitude of anti-schistosomiasis were 14.71% (323/2196) and 11.84% (65/549) in experimental and control groups, and the difference was not significant (χ(2) = 2.98, P > 0.05); the rate of contacting infected water were 15.44% (18 988/122 976) and 15.03% (4622/30 744) in experimental and control group and the difference was not significant (χ(2) = 3.13, P > 0.05); and the infection rate of schistosomiasis of experiment control groups were 9.65% (212/2196) and 10.56% (58/549), the difference was not significant (χ(2) = 0.41, P > 0.05). After one year intervention (2006), the anti-schistosomiasis knowledge awareness rate of experimental and control groups were 97.79% (2032/2078) and 18.11% (98/541), and the different was significant (χ(2) = 1794.31, P < 0.01); the rate of accurate attitude of anti-schistosomiasis were 99.09% (2059/2078) and 13.49% (73/541) in experimental and control group, and the difference was significant (χ(2) = 2077.45, P < 0.01). After 1 - 3 years intervention (2006 - 2008), there were no any contactors with infected water and infectors with schistosome in students of the experiment group in successive 3 years. While in the control group of the same period, the rate contacting infected water were 16.12% (4884/30 296), 11.11% (3079/27 720) and 12.25% (3451/28 168); the infection rate of schistosomiasis were 8.87% (48/541), 7.47% (37/495) and 7.95% (40/503), respectively.</p><p><b>CONCLUSION</b>The intervention model of health promotion, "information dissemination + behavior participation + behavior encouragement", can effectively control and prevent students from infecting schistosoma japonica in heavy endemic areas with schistosomiasis.</p>

Cloning, expression and purification of Schistosoma japonicum ribosomal protein S4 as well as the preliminary study of the diagnostic value of the recombinant protein / 中华预防医学杂志

<p><b>OBJECTIVE</b>To express and purify Schistosoma japonicum ribosomal protein S4(SjRPS4) in Escherichia coli, and assess its value in immunodiagnosis of Schistosomiasis japonica.</p><p><b>METHODS</b>Gene fragment of SjRPS4 was amplified by screening the cercaria cDNA library of Schistosoma japonicum. The target gene was cloned into the expressive vector pQE30 and transformed into E. coli M15. The recombinant protein expression was induced by isopropylthio-β-D-galactoside (IPTG). This fusion protein was purified by Ni(2+)-NTA chromatography and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot and ELISA.</p><p><b>RESULTS</b>The plasmid pQE30/SjRPS4 was constructed successfully and expressed a SjRPS4 fusion protein in E. coli as showing a single special band on SDS-PAGE gel at Mr 30 × 10(3) position. It reached a purity of above 90% after purification. The Western blot result confirmed that the recombinant protein could specifically react with the serum samples from patients of schistosomiasis. Detecting the serum of Schistosomiasis japonica patients by ELISA, the sensitivity and specificity of the ELISA method were 90.91% (70/77) and 92.59% (25/27), the positive rate of recombinant protein expression was 67.30% (70/104). There was no cross-reaction with paragonimiasis patients' serum.</p><p><b>CONCLUSION</b>Protein SjRPS4 was successfully cloned and expressed, and it was confirmed that SjRPS4 antibodies were valuable in the diagnosis of Schistosomiasis japonica.</p>