[Quantitative analysis of gene expression in Pomacea canaliculata infected with Angiostrongylus cantonensis and α - tubulin gene expression in various tissues]

OBJECTIVE

To investigate the expression of some genes in Pomacea canaliculata infected with Angiostrongylus cantonensis, so as to provide insight into the preliminary understanding of the interactions between Angiostrongylus cantonensis and its intermediate host Pomacea canaliculata.

METHODS

P. canaliculata was fed with rat faces containing the first-stage larvae of A. cantonensis. Three to five P. canaliculata was sampled 1, 10 days and 20 days after feeding, and the hemolymph, hepatopancreas, kidney, intestinal tract, head-foot and gill tissues were collected, while uninfected P. canaliculata served as controls. Total RNA was extracted from various tissues of P. canaliculata at different time points post-infection, and transcribed reversely into cDNA. Based on previous transcriptome sequencing results, 10 genes associated with immune defense, signal transduction, cell growth and metabolism, stress response were selected, and the gene expression was determined in the hemolymph tissues of P. canaliculata 1, 10 days and 20 days post-infection with A. cantonensis using real-time fluorescent quantitative PCR assay, and the α-tubulin gene expression was quantified in the hepatopancreas, kidney, head-foot, intestinal tract and gill tissues of P. canaliculata infected with A. cantonensis.

RESULTS

Higher CELA1 gene expression was detected in the infection group than in the control group 1 (t = 12.32, P < 0.05), 10 days (t = 23.51, P < 0.05) and 20 days post-infection (t = 34.92, P < 0.05), and the CELA1 expression increased with the time of infection. The GST gene expression was (7.26 ± 1.80) times higher in the infection group than in the control group 1 day post-infection, and was significantly lower in the infection group than in the control group 10 days (t = 23.89, P < 0.05) and 20 days post-infection (t = 19.83, P < 0.05). Higher ferritin gene expression was found in the infection group than in the control group 10 days post-infection (t = 32.76, P < 0.05), and higher CRT gene expression was seen in the infection group than in the control group 1 (t = 7.23, P < 0.05), 10 days (t = 5.78, P < 0.05) and 20 days post-infection (t = 6.32, P < 0.05). In addition, the greatest α-tubulin gene expression was observed in the the hepatopancreatic tissues of P. canaliculata (F = 17.58, P < 0.05), and the α-tubulin gene expression altered in various tissues of P. canaliculata post-infection with A. cantonensis, with the most remarkable reduction of α - tubulin gene expression seen in the hepatopancreatic tissues (P < 0.05).

CONCLUSIONS

Following A. cantonensis infection in P. canaliculata, the expression of multiple genes is altered, and the expression of α-tubulin gene is inhibited in multiple tissues. The findings provide a basis for the further elucidation of the interactions between P. canaliculata and A. cantonensis.

[Strengthening the development and application of molecular diagnostic techniques to facilitate precision schistosomiasis control in China]

Oncomelania hupensis is the only intermediate host of Schistosoma japonicum, and S. japonicum-infected Oncomelania snail is one of the major risk factor of schistosomiasis transmission. Therefore, the detection of S. japonicum-infected Oncomelania snails plays a vital role in the national schistosomiasis control programmes of China. Recently, a florescent recombinaseaided amplification (RAA) assay, developed by Jiangsu Institute of Parasitic Diseases, has shown rapid, sensitive and simple to detect S. japonicum-infected Oncomelania snails, which deserves expanded experiments.

[Application of solution focused approach in nursing of patients with advanced schistosomiasis]

OBJECTIVE

To investigate the effect of nursing with solution focused approach in advanced schistosomiasis patients.

METHODS

Fifty three patients with advanced schistosomiasis in the Liujiahu Hospital for Schistosomiasis Control of Yiyang City were randomized selected and separated into an intervention group and a control group. The patients of the intervention group received the conventional nursing plus solution focused approach, while the patients of the control group received only the conventional nursing. The effectiveness of nursing and treatment was evaluated in the two groups comparatively.

RESULTS

The knowledge of self-care skills, medical compliance behaviors and services satisfaction degree in the intervention group were higher than those in the control group (χ² = 3.78, 2.87, 4.09 respectively, all P < 0.05). The occurrence rate of upper gastrointestinal bleeding in the intervention group was significantly lower than that in the control group (χ² = 4.894, P < 0.05). The average hospitalization duration of the intervention group was shorter than that of the control group (t = 4.17, P < 0.05).

CONCLUSIONS

The solution focused approach is a feasible and effective method in course of nursing of advanced schistosomiasis patients. It enhances the confidence of the patients and the trustiness of the patients to the health care providers. The complications and the hospitalization duration of the patients are reduced.

[Progress of research on association between schistosomiasis and single nucleotide polymorphisms]

Single nucleotide polymorphisms (SNP) has been regarded as a new genetic marker due to its rich dynamics and relatively stable heredity. SNP can express the relationship between genes and diseases to seek disease-linked genes particularly. A number of domestic and international studies have demonstrated that the formation of schistosomiasis egg granuloma is closely linked to HLA-Ⅱ related antigen. By detecting alleles loci of HLA-Ⅱ gene, researchers can identify the gene or haplotype that is associated with the susceptibility and progression of schistosomiasis. The detected candidate genes can serve useful therapeutic and preventative purposes by providing new technical methods to defeat schistosomiasis. In-depth study on SNP is beneficial to evaluate schistosomiasis inclination clinically, as well as to promote early diagnosis and preventive treatment.

[Preparation of recombinant retrovirus pRevTRE-E77.43 and its protective effect in a mouse model of Schistosoma japonicum infection]

OBJECTIVE

To explore the biological functions of E77.43, a gene segment of Microtus fortis, in treating Schistosoma japonicum infection.

METHODS

Recombinant retroviral vectors of pRevTRE-E77.43 was constructed, and recombinant retroviral vectors were transfected into PA317 cells, and the stable cell lines were obtained by hygromycin screening, followed by the packaging, concentration and purification of recombinant retrovirus. The virus was transferred to the mice infected by S. japonicum via intravenous or intraperitoneal injection, through which the express of target gene and the treatment function in vivo were observed.

RESULTS

The experiment showed the recombinant virus injected mice could efficiently express E77.43 on the 7th day after the injection which lasted for forty-five days thereafter. A significant reduction in adult worms (31.0%) and a high reduction (35.0%) in liver eggs were induced by pRevTRE-E77.43, while the reduction in adult worms and that in liver eggs was 1.2% and 0.9% induced by pRevTRE respectively (t = 3.524, 9.485, both P＜0.01).

CONCLUSIONS

pRevTRE-E77.43 could be used for the treatment of S. japonicum infection, indicating that E77.43 may involve in the natural resistance of M. fortis to S. japonicum infection.

[Study on transcriptome of Oncomelania hupensis before and after Schistosoma japonicum invasion I De novo assembly of data by RNA-Seq]

OBJECTIVE

To produce a comprehensive transcript dataset of Oncomelania hupensis before and after Schistosoma japonicum infection, so as to provide experimental data for perfecting genetic structural information and excavating related molecular markers of O. hupensis infected by S. japonicum.

METHODS

O. hupensis snails were divided into the following 3 groups: one week after S. japonicum miracidium infection, 4 weeks after S. japonicum miracidium infection, and normal condition. Million high-quality reads were obtained from the normalized cDNA of the pooled samples, which were assembled into transcripts.

RESULTS

A total of 63 686 unigenes were identified and were classified into 4 main categories, including general functional prediction (15.36%), signal transduction mechanism (11.75%), posttranslational modification (8.89%), and functional unknown (12.20%).

CONCLUSIONS

The transcriptome information of O. hupensis snail after the invasion of S. japonicum shows that several genes are significantly up-regulated or down regulated expression, and that the availability of transcriptome information might provide a strong foundation for further understanding the schistosome-snail interaction at the molecular level.