[Rapid detection of Schistosoma japonicum-infected snails with recombinase-aided isothermal amplification assay].

OBJECTIVE: To develop a florescent recombinase-aided amplification (RAA) assay for rapid detection of Schistosoma japonicum-infected Oncomelania snails and explore the optimal method for treatment of snail samples. METHODS: Snail samples were divided into 3 groups, and each group consisted of 7 subgroups. There were 50 uninfected snails mixed with 1, 2, 3, 4, 5 and 10 infected snails in the 6 subgroups, respectively, and the remaining subgroup contained 100 uninfected snails mixed with 1 infected snails. DNA was extracted from snails in the three groups using a genomic DNA extraction kit following snail crushing and snail shells removal, crude nucleic acid extraction assay following snail crushing and snail shells removal, and crude nucleic acid extraction assay following direct snail crushing with snail shells preserved, and subjected to florescent RAA and PCR as says. The detection results were compared between the two assays. RESULTS: A florescent RAA assay was developed, which completed the detection of S. japonicum-infected snails at 39 ℃ within 30 min. Following DNA extraction from mass snail samples with a genomic DNA extraction kit following snail crushing and snail shells removal, the lowest detection limit of the florescent RAA assay was one infected snail mixed in 100 uninfected snails, while the lowest detection limit of PCR assay was one infected snail mixed in 50 uninfected snails. Following DNA extraction using crude nucleic acid extraction method following snail crushing and snail shells removal, the lowest detection limit of the florescent RAA assay was one infected snail mixed in 100 uninfected snails, while the lowest detection limit of PCR assay was 3 infected snails mixed in 50 uninfected snails. Following DNA extraction with a crude nucleic acid extraction assay following direct snail crushing with snail shells preserved, the lowest detection limit of the florescent RAA assay was 10 infected snails mixed in 50 uninfected snails, while the lowest detection limit of PCR assay was 10 infected snails mixed in 50 uninfected snails. CONCLUSIONS: A fluorescent RAA assay that is rapid to detect S. japonicum-infected snails in mass snail samples is successfully developed, which is fast, sensitive and easy to perform. Crude nucleic acid extraction following snail crushing and snail shells removal is the optimal method for the treatment of snail samples.

[A path analysis on China's participation in global health governance: a case study of China Aid of Schistosomiasis Control in Zanzibar].

Recently, China's participation in global health governance has been paid increasing global attention. This paper analyzed the current status and needs of African schistosomiasis control, the participation of China and international organizations in African schistosomiasis control and the progress of China Aid of Schistosomiasis Control in Zanzibar, with China Aid of Schistosomiasis Control in Zanzibar as an example. It is suggested that China may improve the capability of participation in global public health governance and international reputation through strengthening intergovernmental and international collaborations, providing successful disease control experiences and products and improving capability and team building.

[Current status and transmission risks of oversea imported schistosomiasis in China].

With the acceleration of the process of global integration, China's international exchanges and cooperation with other countries have been further increased. The personnel exchange has led to the frequent occurrence of imported schistosomiasis from abroad, which seriously endangers people's health. This paper reviews the prevalence and transmission risks of oversea imported schistosomiasis, providing the reference for the entry and exit health quarantine and prevention and control of schistosomiasis in China.

[Evaluation of implementation effect of schistosomiasis control program in Jiangsu Province from 2010 to 2015].

OBJECTIVE: To evaluate the actual effect of the schistosomiasis control program in Jiangsu Province from 2010 to 2015. METHODS: A total of 67 schistosomiasis-endemic counties in 10 cities were selected, and a combination of retrospective investigation and on-site investigation was adopted to collect and record the epidemic data of the counties from 2010 to 2015, and a retrospective survey database of epidemic situation was established. The effects of integrated control strategies with both Oncomelania hupensis snail control and infection source control were evaluated. RESULTS: From 2010 to 2015, 2 465 911 persons who lived in endemic areas were detected for schistosomiasis, with 16 974 positive cases of blood examinations, and 8 positive cases of fecal examinations. Totally 5 145 people with advanced schistosomiasis were treated and 40 460 people with the history of schistosome cercarial-infested water contact received the expanded chemotherapy. A total of 127 636 cattle raised in the endemic areas were detected, and 51 619 cattle (head-times) with the history of cercarial-infested water contact also received the expanded chemotherapy. The area with snails control by molluscicides was 18 604.84 hm2. By the end of 2015, schistosomeinfected snails had not been found and there was no zoological schistosome infection for 5 consecutive years, and in addition, there had been no acute schistosome-infected persons for 6 consecutive years in the whole province. The area with snails dropped to 1 977.18 hm2, with a decreasing rate of 55.24% compared with that in 2010. CONCLUSIONS: After the implementation of the plan for the prevention and control of schistosomiasis in Jiangsu Province (2010-2015), the prevention and control of schistosomiasis has achieved remarkable effects and realized the goal of the plan.

[Establishment of a recombinase-aided isothermal amplification technique to detect Schistosoma japonicum specific gene fragments].

OBJECTIVE: To establish a novel method for the detection of Schistosoma japonicum specific gene fragments by recombinase aided isothermal amplification (RAA). METHODS: The gene fragment SjG28 of S. japonicum was selected as the target gene fragment to be detected, and the primers were designed according to the mechanism of RAA reaction. The reaction of isothermal amplification of S. japonicum was established and optimized. Then this method was applied to amplify and detect the specific gene fragment in the gradient diluent SjG28-recombiant plasmids and different concentrations of S. japonicum genomic DNA to estimate the sensitivity of this method. The samples were also detected by polymerase chain reaction (PCR) in parallel as control. This method was applied to detect the genomic DNA of S. mansoni, Ascaris lumbricoides, and Ancylostoma duodenale to evaluate the specificity. RESULTS: The specific gene fragment was amplified from genomic DNA of adult worms and eggs of S. japonicum by recombinase aided isothermal amplification reaction established in this study. The reaction can be completed within 30 minutes and the minimum detectable template was 20 copies of plasmids or 0.5 ng of genomic DNA per microliter. Other parasites'genomic DNAs, such as S. mansoni, A. lumbricoides, An. duodenale and healthy human blood genomic DNA were not able to be detected by this method. CONCLUSIONS: A novel method for the detection of S. japonicum specific gene fragments by recombinase aided isothermal amplification is established in this study, which can be carried out conveniently and rapidly with a considerable sensitivity and specificity, showing the prospect for application in the diagnosis of schistosomiasis japonica.

[Establishment and application of quality control system for detection of schistosomiasis in Jiangsu Province II Evaluation of pathogenic detection capacity of county-level personnel].

OBJECTIVE: To evaluate the pathogenic detection capacity of county-level organizations in Jiangsu Province, and to improve the field schistosomiasis detection capacity of professional personnel, thus to provide the technical support for the construction of quality control system of schistosomiasis field detection. METHODS: The eggs of Schistosoma japonicum were obtained from rabbit schistosomiasis models and were produced into suspensions at four different concentrations. The county-level workers were invited to hatch the eggs, and the accuracy, detection error rate and omission rate were compared between the detection results and the standard results. The single-blind method was used in the capacity examination. RESULTS: A total of 560 suspensions were detected by 28 counties (districts, cities), and 283 positive samples and 203 negative samples were detected. The total accuracy was 86.79%, total error rate was 9.38%, and total omission rate was 15.77%. The difference between the detection result and standard result was statistically significant (χ2 = 12.99, P < 0.01) . Twenty out of 28 counties (districts, cities) had omission detections, accounting for 71.43%; and 13 had fault detections, accounting for 46.43%. The error rates of workers from the river marshland, hilly areas, water networks, and lake marshland ranged from 4.55% to 43.75%, and the difference was statistically significant (χ2 = 30.34, P < 0.01). The omission rate ranged from 4.17% to 20.45%, and the difference was not statistically significant (χ2 = 5.09, P = 0.17) . The error rates and omission rates of workers from the transmission control areas and transmission interruption areas were 7.50%, 13.33% and 10.42%, 17.13%, respectively, and the differences were not statistically significant (χ2 = 0.229, 0.575, both P > 0.05) . The error rates and omission rates of workers from the areas with or without at least ten years history of transmission control were 11.81%, 5.00% and 16.67%, 14.17%, respectively, and the differences were not statistically significant (χ2 = 2.804, 2.848, both P > 0.05) . The error rates of workers from the areas with or without at least ten years history of transmission interruption were 11.54% and 10.00%, respectively, and the difference was not statistically significant (χ2 = 0.069, P = 0.792), while the correspondent omission rates were 10.90% and 35.00% respectively, and the difference was statistically significant (χ2 = 17.364, P < 0.01) . CONCLUSIONS: The detection error and omission exist in the schistosomiasis examinations in the county-level organizations in Jiangsu Province, and therefore, the field pathogen detection capacity of the professional personnel needs to be further improved.

[MRI findings of cerebral schistosomiasis in acute stage：establishment of experimental model of acute cerebral schistosomiasis with rabbits].

OBJECTIVE: To establish an experimental model of acute cerebral schistosomiasis japonica and explore the MRI manifestations of acute cerebral schistosomiasis. METHODS: Rabbits were divided into 3 groups with 10 rabbits in each group. The rabbits in the experimental group were directly injected with suspension fluid of Schistosoma japonicum eggs (0.9 mg, 1 ml) by the cranial drilling method, those in the negative control group were given saline (1 ml) by the same method above-mentioned, and those in the blank control group were not given any treatment. Antibiotic was given to the first two groups after the operation. The clinical manifestations of the 3 groups were observed, and the magnetic resonance imaging (MRI) was performed in 30 days post-operation, and then the brain tissues were taken for pathological examinations. RESULTS: All the rabbits in the experimental group exhibited inappetence, various neurological symptoms including hemiplegia, and weight loss after the operation; while those in the negative control group showed inappetence in 3 days after the operation, and 1 week later, the symptom disappeared; there were no adverse reactions in the blank control group. MRI of the experimental group showed nodular or patchy enhancement on T1WI enhancement, brain edema, abnormal ventricular dilatation, and needle augmentation. SWI displayed hypointense in the abnormal enhanced nodules and flaky hypointense on the operation brain. In the negative control group, 2 rabbits showed abnormal enhancement of the needle canal, and 1 showed mild dilatation of the ventricle. The blank control group showed normal manifestations. The pathological examinations showed abnormal appearances in 10 rabbits of the experimental group, including 6 with S. japonicum egg granuloma nodules, nonspecific granuloma nodules coexisted with perivascular inflammation; no granuloma nodules were found in the negative control group, but 2 rabbits showed vascular inflammation; the blank control group showed the normal brain tissue. CONCLUSIONS: An experimental model of acute cerebral schistosomiasis is successfully established in rabbits by intracranial injection of schistosome eggs. The MRI examination combined with the clinical manifestations can improve the accuracy of early diagnosis of cerebral schistosomiasis.

Stromal Derived Factor-1/CXCR4 Axis Involved in Bone Marrow Mesenchymal Stem Cells Recruitment to Injured Liver.

The molecular mechanism of bone marrow mesenchymal stromal stem cells (BMSCs) mobilization and migration to the liver was poorly understood. Stromal cell-derived factor-1 (SDF-1) participates in BMSCs homing and migration into injury organs. We try to investigate the role of SDF-1 signaling in BMSCs migration towards injured liver. The expression of CXCR4 in BMSCs at mRNA level and protein level was confirmed by RT-PCR, flow cytometry, and immunocytochemistry. The SDF-1 or liver lysates induced BMSCs migration was detected by transwell inserts. CXCR4 antagonist, AMD3100, and anti-CXCR4 antibody were used to inhibit the migration. The Sprague-Dawley rat liver injury model was established by intraperitoneal injection of thioacetamide. The concentration of SDF-1 increased as modeling time extended, which was determined by ELISA method. The Dir-labeled BMSCs were injected into the liver of the rats through portal vein. The cell migration in the liver was tracked by in vivo imaging system and the fluorescent intensity was measured. In vivo, BMSCs migrated into injured liver which was partially blocked by AMD3100 or anti-CXCR4 antibody. Taken together, the results demonstrated that the migration of BMSCs was regulated by SDF-1/CXCR4 signaling which involved in BMSCs recruitment to injured liver.

[Schistosomiasis surveillance after interruption of schistosomiasis transmission in Xiuzhou District, Jiaxing City].

OBJECTIVE: To analyze the endemic situation of schistosomiasis after its interruption of transmission in Xiuzhou District, Jiaxing City, Zhejiang Province, so as to provide the references for future surveillance work. METHODS: The data of schistosomiasis and Oncomelania hupensis snails in Xiuzhou District were collected and analyzed statistically. RESULTS: From 1994 to 2015, totally 975 village-times were investigated for O. hupensis snails, and the accumulated area of 4 385.31 hm2 was surveyed. Twenty former snail sites were reoccurring, with an area of 32.61 hm2. An area of 57.71 hm2 was supplied with snail eradication measures. Totally 11 941 snails were dissected and no schistosome infected snails were found. The serum and stool tests were performed to 221 794 and 3 731 residents respectively, and no local infection cases but four imported cases were found. CONCLUSIONS: The endemic situation of schistosomiasis in Xiuzhou District is stable after the transmission was interrupted. However, there are imported schistosomiasis cases, and therefore, the prevention of imported infection source is the focus of surveillance work.

[Effect of comprehensive schistosomiasis control measures in Kaihua County from 1996 to 2015].

OBJECTIVE: To evaluate the control effect of comprehensive measures of schistosomiasis after its transmission interruption in Kaihua County, Zhejiang Province, so as to provide the references for further consolidation of schistosomiasis control. METHODS: The data of Oncomelania hupensis snail survey and control, as well as environmental reform in Kaihua County were collected and analyzed from 1996 to 2015. RESULTS: From 1996 to 2015, totally 2 635 snail habitats and 102.75 hm2 area with snails were found, and 125.4 thousand snails were dissected and no one was schistosome infected. The accumulated snail control area was 4 932.98 hm2, and the area with snails was effectively reduced by the comprehensive control measures. CONCLUSIONS: The schistosomiasis control effect could be consolidated by the comprehensive control measures emphasizing environmental reconstruction, and the snail surveillance work still should be strengthened.

Prediagnostic methods for the hemolysis of herbal medicine injection.

ETHNOPHARMACOLOGICAL RELEVANCE: The Xue-Sai-Tong injection, a traditional Chinese medicine injection with total saponins extracted from Sanchi Ginseng, has been used for more than half a hundred years to treat coronary artery disease. The study is to establish a prediagnostic method for the hemolytic adverse effect of herbal medicine injection by taking Xue-Sai-Tong injection as an example. MATERIALS AND METHODS: A new method named "fuzzy dissemination" was established to identify the hemolytic ginsenosides in Xue-Sai-Tong injection on the basis of fuzzy changes of individual ginsenosides in the injections altered by re-adding the fractions prepared from the total saponins and statistic analysis between hemolytic degrees and individual ginsenosides. Related substances test, safety tests and fingerprints of the injections in different batches were tested. RESULTS: HD(50), P(50) and interactions on hemolysis of individual ginsenosides were examined. Experiment indicated that the content of Rg(1), Rg(2), M(51) (an unknown ingredient with retention time at 51 min in HPLC) and M(70) in Xue-Sai-Tong injection showed a significant positive correlation with hemolytic degree, and the content of R(1), Re, Rb(1) and Rd showed a significant negative correlation with hemolytic activity. Furthermore HD(50) of injection exhibits superiority to other tests for the hemolysis of injections. Abnormal hemolysis in some batches of injections was observed, but there were no significant differences among injections of different batches in related substances test, safety test and fingerprints. CONCLUSIONS: This is an original method to analyze active ingredients of a complicated integrity instead of studying on individual ingredients, it showed that the interactions of some individual ginsenosides and some unknown micro-ingredients in Xue-Sai-Tong injection were the major factors causing hemolysis, and this method could also be utilized in research of corresponding aspects. HD(50) of injection can reflect the changes of hemolytic property of injections caused by not only the change of active constituents of injection, but also the auxiliary materials. Thus it was recommended as an index for the hemolytic prediagnosis of the injections in practice.