In vivo efficiency of praziquantel treatment of single-sex Schistosoma japonicum aged three months old in mice.

Schistosomiasis is a major neglected tropical disease mainly caused by Schistosoma haematobium, S. japonicum and S. mansoni, and results in the greatest disease burden.

[Study on biological characteristics: reproduction and viability of as an intermediate host of ].

Objective: To compare the difference of fertility of snails between self-fertilization and cross-fertilization and to observe the circadian rhythm of laying eggs, the effect of light on laying eggs and the tolerance of the snail to water and food deficiency, so as to provide the evidence for control and elimination of snails in the field.

Methods: Under laboratory conditions, a single egg for self-fertilization was separated and hatched individually, and young snails were raised in different plastic boxes individually. The eggs for cross-fertilization were hatched and the young snails were fed in the same plastic box.

[Studies on resistance of to praziquantel XVII Biological characteristics of praziquantel-resistant isolates of in mice].

Objective: To investigate the biological characteristics of the praziquantel-resistant isolate of in mice, so as to explore the pathogenicity to definitive hosts and transmission intensity of the praziquantel-resistant isolate of .

Methods: Mice were infected with the cercariae released from two praziquantel-resistant isolates and two praziquantel-susceptible isolates of . The mouse- snail-mouse cycle was established and maintained in the laboratory.

[Studies on resistance of to praziquantel XⅥ Biological characteristics of praziquantel-resistant isolates of in snails].

Objective: To investigate the difference of biological characteristics between the praziquantel-resistant and -susceptible isolates of in intermediate host snails.

Methods: Mice were infected with cercariae of praziquantel-resistant and -susceptible isolates of , and the parasite eggs were collected 37 days post-infection to hatch miracidium. Then, the snails were infected with the miracidium of each parasite isolate.

[Role of goat in transmission of schistosomiasis japonica III Effect of temperature and humidity on survival of eggs in goat feces and egg survival in natural environments].

Objective: To investigate the survival of Schistosoma japonicum eggs in goat feces in natural marshlands and the factors affecting its survival, so as to provide evidences for understanding of the role of eggs in goat feces in the transmission of schistosomiasis and the development of the interventions pertaining to disease control and elimination.

Methods: The goat animals of schistosomiasis japonica were modeled in laboratory, and the feces of infected goat were collected. In laboratory, the effects of environmental temperature and water content in goat feces on egg hatching were evaluated, and in the field, the effect of duration of goat feces on marshland on egg hatching and the effect of direct sunshine on egg survival were evaluated.

[Role of goat in transmission of schistosomiasis japonica III Development of goat feces collector and optimization of fecal hatching technique].

Objective: To develop a simple, feasible goat feces collector to improve the collection accuracy and integrity of goat fecal samples without pollution, and to modify the miracidium hatching test with a plastic tube to achieve simple, standard and comparative procedures, so as to provide technical support for pathogenic diagnosis and scientific research of goat schistosomiasis japonica.

Methods: According to the body features of goat in marshland regions, a goat fecal collector, which was made of coarse fabric cottons, was devised, which was able to be fixed onto the goat buttocks and avoid urine pollution. Prior to miracidium hatching test, the goat fecal samples were pieced by using a mechanical method instead of the conventional artificial piecing method, and the effect of mechanical piecing treatment on miracidium hatching was evaluated.

[Role of goat in transmission of schistosomiasis japonica III Environmental contamination by goat feces and prediction of environments at high risk of infection].

Objective: To quantitatively estimate the range and area of environmental contamination by the feces of -infected that were freely grazed, so as to provide the theoretical evidence for the scientific assessment of the role of the freely grazed goat in the transmission of schistosomiasis japonica and development of control strategy.

Methods: All the fecal samples excreted by the infected goat at daytime (12 h) were collected by using a self-made goat fecal collector, weighed and counted. The quantity and dispersal of the feces excreted by the freely grazed goat at daytime under a natural condition were investigated, and the walking route and speed of the freely grazed goat at daytime were recorded with a multifunction GPS data logger.

[Surveillance and forecast system of schistosomiasis in Jiangsu Province. VI. Detection technology of water infectivity based on enrichment of Schistosoma japonicum cercariae on water surface].

Objective: To explore the enrichment technique of Schistosoma japonicum cercariae on the water surface, so as to establish a new method combined with the existing technology to detect the cercarial infested water body quickly and sensitively.

Methods: Soybean oil, gasoline, kerosene and isophorone were screened as expanding agents. The cercariae were enriched by the thrust of the expanding agents when diffusing on the water surface, and PE adsorption film and C-6 film were applied to seize them so as to determine the infectivity of the water quickly.

[Cloning and expression of Schistosoma japonicum VCP gene and its mRNA expression levels in different stages].

Objective: To prokaryotically express the valosin-containing protein (VCP) of Schistosoma japonicum, and analyze its VCP mRNA expressions in the cercaria, schistosomulum, adult worm (female and male worms) and egg.

Methods: RNA of S. japonicum eggs were extracted, and reversely transcribed into cDNA.

Resistance to niclosamide in Oncomelania hupensis, the intermediate host of Schistosoma japonicum: should we be worried?

As the currently only available molluscicide, niclosamide has been widely used for snail control for over 2 decades in China. There is therefore a concern about the emergence of niclosamide-resistant snail populations following repeated, extensive use of the chemical. The purpose of this study was to investigate the likelihood of niclosamide resistance in Oncomelania hupensis in China.

[Preparation and molluscicidal effect of 5% niclosamide ethanolamine granules].

Objective: To explore the preparation of 5% niclosamide ethanolamine granules and evaluate its molluscicidal effect.

Methods: The optimal formula was obtained by the selection of wetting agents, dispersants, adhesives and carriers. The molluscicidal effect of 5% niclosamide ethanolamine granules was measured by the spray methods in the laboratory and field.

Efficacy of artemether and artesunate in mice infected with praziquantel non-susceptible isolate of Schistosoma japonicum.

Praziquantel is currently the only drug of choice for the treatment of human Schistosoma japonicum infections, and praziquantel-based chemotherapy has been proved to be generally effective to control the morbidity and reduce the prevalence and intensity of S. japonicum infections. However, the potential emergence of praziquantel resistance in S.

Is there a reduced sensitivity of dihydroartemisinin against praziquantel-resistant Schistosoma japonicum?

Praziquantel is currently the only drug of choice for the treatment of human schistosomiases. However, it has been proved that Schistosoma japonicum subjected to drug pressure may develop resistance to praziquantel. To evaluate the efficacy of dihydroartemisinin against praziquantel-resistant S.

In vivo activity of dihydroartemisinin against Schistosoma mansoni schistosomula in mice.

Dihydroartemisinin, an anti-malarial agent, has been shown to exhibit activity against Schistosoma japonicum and S. mansoni. The purpose of the present study was to investigate the in vivo activity of dihydroartemisinin against juvenile S.

[Studies on resistance of Schistosoma to praziquantel XIIV sensitivity of Schistosoma japonicum to praziquantel in marshland and lake endemic regions of Chinese Mainland].

Objective: To compare the sensitivities of different isolates of Schistosoma japonicum in marshland and lake regions of Chinese Mainland to praziquantel, so as to provide experimental evidence for establishing the techniques of detecting and monitoring praziquantel sensitivity.

Methods: Mice were infected with cercariae released from the S. japonicum-infected snails collected from the marshland and lake endemic regions of Hunan, Hubei, Jiangxi, Anhui and Jiangsu provinces, grouped, and treated with praziquantel at single oral doses of 37.

[Distribution of niclosamide spreading oil on water surface and its efficacy against cercariae of Schistosoma japonicum].

Objective: To investigate the distribution and spreading speed of niclosamide spreading oil, as well as its effect against cercariae of Schistosoma japonicum.

Methods: The foamed plastic with a diameter of 4 mm served as a buoyage, which was placed at the center of the still water surface. The niclosamide spreading oil was dropped at 0.

[Studies on standardization of methods for screening molluscicides in laboratory IV sensitivity of Oncomelania snails from different months to niclosamide].

Objective: To understand the sensitivity of Oncomelania snails collected from different months to niclosamide, so as to provide the scientific evidence for the standardization of methods for molluscicide screening and efficacy evaluation in laboratory.

Methods: The snails collected from the marshland of Zhenjiang City, Jiangsu Province month by month from June 2010 to May 2011. After being raised in laboratory for 24 h, the snails were randomly grouped, and then immersed in different concentrations of 50% wettable powder formulation of niclosamide ethanolamine salt at (25 +/- 1) degrees C with a humidity of 60%.

[Studies on resistance of Schistosoma to praziquantel XIV experimental comparison of susceptibility to praziquantel between PZQ-resistant isolates and PZQ-susceptible isolates of Schistosoma japonicum in stages of adult worms, miracidia and cercariae].

Objective: To investigate the changes of sensitivity to praziquantel (PZQ) about PZQ-resistant isolates of Schistosoma japonicum established in laboratory by means of the resistance-inducement method during the stages of adult worms, cercariae and miracidia, so as to provide the basis for establishing the sensitivity-detecting technique to praziquantel.

Methods: A Jiangsu laboratory-maintaining isolate and a Hunan field-collecting isolate of S. japonicum that were never treated with PZQ were as PZQ-susceptible isolates, and two PZQ-induced isolates that were established via drug-treated passage in laboratory were as PZQ-resistant isolates.

[Studies on resistance of Schistosoma to praziquantel XIII resistance of Schistosoma japonicum to praziquantel is experimentally induced in laboratory].

Objective: To investigate the possibility of the emergence of praziquantel resistance in Schistosoma japonicum in Mainland China under drug pressure.

Methods: S. japonicum cercaria were released from the infected Oncomelania hupensis snails collected from the marshland in Hunan Province that was endemic for schistosomiasis japonica and raised in the laboratory of Jiangsu Institute of Parasitic Diseases, and mice were infected.

[Studies on spray of niclosamide ethanolamine salt. I. development and effect assessment of spray of niclosamide ethanolamine salt].

Objective: To develop a spray of niclosamide ethanolamine salt for prevention of bovine from Schistosoma japonicum infection, and explore its characteristics and effect.

Methods: The solubilizers, penetrating agents, emulsifiers were screened, and the spray of niclosamide ethanolamine salt was formulated according to the screening results. The niclosamide ethanolamine salt was determined by using a HPLC technique, and the stability was observed.

[Study on preservation of niclosamide in water samples].

Objective: To investigate the preservation condition of niclosamide in water samples and establish a high performance liquid chromatography (HPLC) method by solid-phase extraction (SPE) which is used for determination and preservation of niclosamide in water samples.

Methods: Under the simulated setting in laboratory, niclosamide was formulated into the solutions of 0.50, 1.

[Surveillance and forecast system of schistosomiasis in Jiangsu Province. IV. Establishment of Schistosoma japonicum cercaria-killing method by spraying niclosamide suspension on water surface].

Objective: To investigate the effect of suspension concentrate of niclosamide (SCN) on killing cercariae of Schistosoma japonicum on water surface, optimization and impact on fish, so as to establish an emergency-treatment intervention for rapidly killing cercariae and eliminating water infectivity.

Methods: SCN was formulated into different concentrations of solutions, and then the solutions were sprayed on the surface of water containing S. japonicum cercariae.

A strategy for emergency treatment of Schistosoma japonicum-infested water.

Background: Schistosomiasis japonica, caused by contact with Schistosoma japonicum cercaria-infested water when washing, bathing or production, remains a major public-health concern in China. The purpose of the present study was to investigate the effect of a suspension concentrate of niclosamide (SCN) on killing cercaria of S. japonicum that float on the water surface, and its toxicity to fish, so as to establish an emergency-treatment intervention for rapidly killing cercaria and eliminating water infectivity.