microRNAs expression profiles in Schistosoma japonicum of different sex 14 and 28 days post-infection

Different miRNAs are involved in the life cycles of Schistosoma japonicum. The aim of this study was to examine the expression profile of miRNAs in individual S. japonicum of different sex before and after pairing (18 and 24 dpi). The majority of differential expressed miRNAs were highly abundant at 14 dpi, except for sja-miR-125b and sja-miR-3505, in both male and female. Moreover, it was estimated that sja-miR-125b and sja-miR-3505 might be related to laying eggs. sja-miR-2a-5p and sja-miR-3484-5p were expressed at 14 dpi in males and were significantly clustered in DNA topoisomerase III, Rap guanine nucleotide exchange factor 1 and L-serine/L-threonine ammonia-lyase. Target genes of sja-miR-2d-5p, sja-miR-31- 5p and sja-miR-125a, which were expressed at 14 dpi in males but particularly females, were clustered in kelch-like protein 12, fructose-bisphosphate aldolase, class I, and heat shock protein 90 kDa beta. Predicted target genes of sja-miR-3483-3p (expressed at 28 dpi in females but not in males) were clustered in 26S proteasome regulatory subunit N1, ATPdependent RNA helicase DDX17. Predicted target genes of sja-miR-219-5p, which were differentially expressed at 28 dpi in females but particularly males, were clustered in DNA excision repair protein ERCC-6, protein phosphatase 1D, and ATPase family AAA domaincontaining protein 3A/B. Moreover, at 28 dpi, eight miRNAs were significantly up-regulated in females compared to males. The predicted target genes of these miRNAs were significantly clustered in heat shock protein 90 kDa beta, 26S proteasome regulatory subunit N1, and protein arginine N-methyltransferase 1. To sum up, differentially expressed miRNAs may have an essential role and provide necessary information on clarifying this trematode's growth, development, maturation, and infection ability to mammalian hosts in its complex life cycle, and may be helpful for developing new drug targets and vaccine candidates for schistosomiasis.

Parasitological and molecular detection of human fascioliasis in a young man from Guizhou, China

A 24-year-old man born in Guizhou province was diagnosed with obstructive jaundice and bile duct stones in 2013. Four living trematodes were found during laparotomy and cholecystectomy. Based on the morphology and molecular genetics analysis of internal transcribed spacer and pcox1 genes of the flatworm specimens, the trematodes from the patient were confirmed to be Fasciola hepatica. This report provided the clinical and molecular diagnosis information on human fascioliasis, which is an emerging sanitary problem still ignored in China. Human fascioliasis constantly occurs due to climatic changes and frequency of human travel. Therefore, it deserves more attention from physicians working in both developing and developed countries.

[The clinical characteristics and two different treatment outcomes of 321 patients with hypopharyngeal squamous cell carcinoma]

Objective:To investigate the clinical characteristics, two different treatment outcomes and prognostic factors of hypopharyngeal carcinoma. Method:The life table method was used to calculate the overall survival rates, Log-rank test was used to compare the overall survival rates between the two groups．The Cox proportional hazard model was used to perform the multivariate analysis to confirm independent treatment modalities as prognostic factors. Result:Among the 321 patients, 197 patients received surgery combine with radiotherapy or concurrent chemoradiotherapy treatment（S+R/CRT） and 124 patients received radiotherapy or concurrent chemoradiotherapy treatment(R/CRT). For 321 patients, the 1,3,5year overall survival rates were 75.87%,49.39%,41.38% and the median survival time was 37.65 months. The difference in throat retention ratio between the radiotherapy or concurrent chemoradiotherapy treatment(41.94%) and surgery combine with radiotherapy or concurrent chemoradiotherapy treatment（11.17%) was statistically significant (P<0.01).Univariate analysis showed that clinical stage of tumor, T stage, N stage, M stage and two different treatment modalities have impact on survival prognosis. Cox regression multivariate analysis showed that T stage, N stage, two different treatment modalities were independent risk factors of prognosis. Conclusion:The overall prognosis of hypopharyngeal carcinoma was poor and dismal. Hypopharyngeal carcinoma is characterized by high degree of malignancy, difficult to be found early, prone to recurrence and metastasis after operation, large trauma and poor prognosis. Comprehensive examination should be conducted to define the stage of tumor and choose the rational treatment plan before treatment. Surgery combine with radiotherapy or chemotherapy treatment modality is still the main treatment strategy for advanced-stage hypopharyngeal carcinoma..

Identification and characterization of the causative triatomine bugs of anaphylactic shock in Zhanjiang, China

Background

Two health concerns primarily related to triatomine bugs are transmission of Trypanosoma cruzi through infective feces, and allergic reactions induced by triatomine bites. In the Southwestern United States, reduviid bugs bites commonly cause insect allergy. In South China, four cases of anaphylactic shock have been reported after this bite exposure. To further classify the species of these bugs and confirm the sensitization of the triatomine saliva, we caught triatomine bugs from the region where the bites occurred and performed phylogenetic and immunohistochemical (IHC) analysis.

Methods

Triatomine bugs were collected in Donghai Island of Zhanjiang City in South China. The genomic DNA was extracted from three legs of the bugs. The fragments of mitochondrial 16S rRNA, cytochrome c oxidase subunit I (COI) gene and nuclear ribosomal 18S and 28S rRNA genes were obtained by PCR and sequenced. A phylogenetic tree was constructed based on the sequence of 16S rRNA gene using a maximum likelihood method with MEGA 7.0 software. Trypanosomal specific fragments and vertebrate COI genes were amplified from the fecal DNA to detect the infection of trypanosomes and analyze the blood feeding patterns, respectively. Paraffin-embedded sections were then prepared from adult triatomines and sent for IHC staining.

Results

We collected two adult triatomine bugs in Donghai Island. Morphological and molecular analyses indicated that the triatomines were Triatoma rubrofasciata. No fragments of T. cruzi or other trypanosomes were detected from the fecal DNA. Mitochondrial gene segments of Homo sapiens and Mus musculus were successfully amplified. The allergens which induced specific IgE antibodies in human serum were localized in the triatomine saliva by IHC assay.

Conclusions

The two triatomine bugs from Donghai Island were T. rubrofasciata. They had bitten humans and mice. Their saliva should contain the allergens related to the allergic symptoms and even anaphylactic shock of exposed residents. Great consideration should be given to this triatomine bugs due to their considerable distribution and potential threat to public health in South China.

[Advances on the research of the environmental risk factors of children autism]

Autism spectrum disorder is a lifelong neurodevelopmental disorder, characterized by social interaction and communication impairments, accompanied by repetitive behaviors. Little is known about the causes and contributing factors for autism. It is difficult to prevent and cure, and has become a globe public health problem. With the development in the prevalence of autism, the idea how the environmental factors cause the autism, gains all attentions. Summarizing latest epidemiological studies and experimental evidence, this review is focused on the effect of environmental factors, including air pollutant, heavy metal and pesticides, and discussed the relation between environmental risk factors and autism. The results showed that risks of autism in children may increase following in prenatal exposure to air pollutants, heavy metal and pesticides. It is needed to do the research on the mechanism of environmental risk factor and autism for more prevention, treatment and control suggestions.

Development of Lateral Flow Immunoassay for Antigen Detection in Human Angiostrongylus cantonensis Infection

Angiostrongyliasis is difficult to be diagnosed for the reason that no ideal method can be used. Serologic tests require specific equipment and are not always available in poverty-stricken zone and are time-consuming. A lateral flow immunoassay (LFIA) may be useful for angiostrongyliasis control. We established a LFIA for the diagnosis of angiostrongyliasis based on 2 monoclonal antibodies (mAbs) against antigens of Angiostrongylus cantonensis adults. The sensitivity and specificity were 91.1% and 100% in LFIA, while those of commercial ELISA kit was 97.8% and 86.3%, respectively. Youden index was 0.91 in LFIA and 0.84 in commercial ELISA kit. LFIA showed detection limit of 1 ng/ml of A. cantonensis ES antigens. This LFIA was simple, rapid, highly sensitive and specific, which opened an alternative approach for the diagnosis of human angiostrongyliasis.

[Status of Clonorchis sinensis infection and its influencing factors among migrant workers in Baoan District, Shenzhen City]

OBJECTIVE

To understand the status of Clonorchis sinensis infection and its risk factors among migrant workers in Baoan District of Shenzhen City, so as to provide the evidence for the development of control strategies.

METHODS

A total of 642 migrant workers were chosen as the investigation samples by the stratified cluster sampling method. Their sera were collected and tested for Clonorchis sinensis infection with ELISA, and a questionnaires survey was performed to collect the information of clonorchiasis sinensis related to knowledge and behaviors. The influencing factors were summarized with the case-control study method.

RESULTS

A total of 642 subjects were investigated, in which 530 subjects received the serological examinations and the positive rate was 6.6% (35/530). The significant differences were not found between genders (Chi2 = 1.19, P = 0.28) or among the age groups (Chi2 = 0.45, P = 0.80). The awareness rates of knowing infection route, health hazard and prevention knowledge were 50.16%, 33.64% and 27.41%, respectively. The rates of healthy behaviors such as not eating semi-cooked fish, not feeding pets with raw fish or shrimps, and differentiating between the raw and cooked food when using cutting boards were 80.67%, 78.41% and 45.95%, respectively. The awareness rate of prevention knowledge was positively related to the infection (OR = 0.16, P < 0.01).

CONCLUSION

The prevention and control of Clonorchis sinensis infection among migrant workers could not be neglected, and the health education should be strengthened.

Monoclonal antibody 12D5 inhibits eosinophil infiltration in the brain of Angiostrongylus cantonensis-infected BALB/c mice

Each of BALB/c mice was infected with 50 Angiostrongylus cantonensis larvae. One group of mice received an intraperitoneal injection of 50 μg 12D5 monoclonal antibody (mAb) against a 98 kDa antigen of adult worms at 10 days post-infection (dpi), with a booster injection of 25 μg at 12 dpi. Five mice from each group were sacrificed at 14 dpi for pathological examination and RNA extraction. The infiltration of eosinophils and severity of eosinophilic meningitis were reduced in 12D5 mAb-treated mice compared with the infected mice without 12D5 treatment. The levels of eotaxin mRNA expression in spleen significantly increased and the expression of the Th2-type cytokine IL-5 significantly decreased. However, the expression of IL-4 was not changed. 12D5 mAb can observably enhance the survival rate of infected mice and reduce symptoms of angiostrongyliasis. A. cantonensis infection is a major cause of eosinophilic meningoencephalitis. The results of this study could be helpful for the development of treatment of human angiostrongylosis.

Seroprevalence of Angiostrongylus cantonensis infection in humans in China

A seroepidemiological survey was carried out in China during 2009-2010 to determine the extent of circulating antigens (CAg) for Angiostrongylus cantonensis in the Chinese population using the gold immunochromatographic assay, with the objective of elucidating the nationwide prevalence of angiostrongyliasis in China. A total of 1,730 blood samples was collected and assayed from the general adult population (the "general group"), and those involved in aquaculture or processing of snails Achatina fulica and Pomacea canaliculat (the "occupational group") from 5 provinces (Fujian, Hunan, Guangdong, Guangxi, and Zhejiang) and 1 municipal city (Beijing). The overall seroprevalence for the "occupational group" was 7.4% (40/540), which was significantly higher (P < 0.001) than that of the "general group" (0.8%, 9/1,190). The seroprevalence in males (9.5%) was significantly higher than in females (4.2%) (P < 0.05). These results demonstrate that angiostrongyliasis represents a significant zoonotic disease in China, requiring the strengthening of food safety for control of this food-borne disease.

FOXO3a is involved in the apoptosis of naked oocytes and oocytes of primordial follicles from neonatal rat ovaries

Inhibition of the forkhead transcription factor, FOXO3a, can promote the transition from primordial to primary follicle and subsequent follicle development in mammalian ovaries. Stem cell factor (SCF) initiates anti-apoptotic signaling from its membrane receptor, c-kit, to Bcl-2 family members through PI3K/AKT in oocytes of primordial follicles. However, whether FOXO3a mediates the apoptosis of naked oocytes and oocytes of primordial follicles remains unknown. In the present study, oocytes from nests and primordial follicles from neonatal rat ovaries were cultured, and oocyte apoptosis was examined using the TUNEL technique. The pro-apoptotic action of FOXO3a and the potential signal transduction pathways were investigated using RT-PCR, Western blot, and immunocytochemistry. Culturing oocytes in the presence of SCF did not affect the level of total FOXO3a protein, but rapidly elevated the level of phosphorylated FOXO3a (indicating functional suppression). As phosphorylated FOXO3a increased, oocyte apoptosis was inhibited. The specific PI3K/Akt inhibitor, LY 294002, abolished the phosphorylation of FOXO3a and the anti-apoptotic action of SCF. SCF down-regulated the expression of p27KIP1 and pro-apoptotic factors such as Bim, Bad, and Bax, and this activity was reversed by LY 294002. SCF up-regulated the expression of MnSOD, which was also inhibited by LY 294002. However, SCF had no effect on Bcl-2 protein. These results suggest that FOXO3a is involved in oocyte apoptosis in the neonatal rat ovary, and the SCF-PI3K/Akt-FOXO3a signaling pathway mediates oocyte apoptosis and primordial follicle formation.

[Study on the epidemiological characteristics and natural infectious focus of Angiostrongylus cantonensis in Shenzhen area of Zhujiang Delta in China]

OBJECTIVE

To delimit the natural infectious focus, including the distribution of wildlife, species, ecology of intermediate hosts and final host of Angiostrongylus cantonensis, as well as the routes of transmission and epidemiological characteristics and wildlife of human Angiostrongylus cantonensis, based on human diverging cases identified in Shenzhen, southern area of China.

METHODS

Data including rate of infection and density of Angiostrongylus cantonensis among different hosts in 12 different areas in Shenzhen was collected, using microscope to inspect homogenate liquids of snails. Wild mice were captured with mouse cage to examine the adult Angiostrongylus cantonensis. Using larva isolated from wild-snails-infected rats to observe the life cycle of Angiostrongylus cantonensis.

RESULTS

Wild life of Angiostrongylus cantonensis existed in the southwest part of Shenzhen with its majority intermediate hosts as Achatina fulica. The overall rate of infection was 31% in wildlife and final host was found to be Rattus andersoni, Achatina fulica which were extensively distributed in the shrub region of Shenzhen because of suitable climate, humidity and vegetation for generating the life cycle of Achatina fulica. Human infected Angiostrongylus cantonensis was mainly due to eating raw snails or vegetables contaminated by larva of Angiostrongylus cantonensis. The peak of infection was seen from April to November in Shenzhen area.

CONCLUSION

Wildlife of Angiostrongylus cantonensis existed in the southwest part of Shenzhen with major wildlife reservoir including fresh water snail and wild mouse. The existence of natural focus Angiostrongylus cantonensis was now recognized as an important source of human angiostrongyliasis in Shenzhen area.

Identification of differentially expressed genes in female Culex pipiens pallens

Culex pipiens pallens is the mosquito vector of a number of human pathogens such as Wuchereria bancrofti, Brugia malayi, and epidemic encephalitis B virus. Female C. pipiens pallens play an important role in transmitting pathogens by sucking blood, which is essential for reproduction. In the present study, a subtractive cDNA library for female C. pipiens pallens was constructed by the suppression subtractive hybridization (SSH) technique and then 100 clones from the female SSH library were sequenced and analyzed. Female-differentially expressed genes in C. pipiens pallens were screened using semiquantitative RT-PCR. The full-length cDNA of an EST sequence (fs68) that was specifically expressed in female C. pipiens pallens was characterized by 3' and 5' rapid amplification of cDNA ends (RACE). The characteristics of the female-specific gene were further analyzed using bioinformatics and Northern blot. It was shown that the female-specific gene was a previously uncharacterized gene and may encode a salivary peptide. This putative salivary peptide could be a very important molecule in the blood feeding of female C. pipiens pallens.

[Expression of truncated Toxoplasma gondii GRA8 in the prokaryotic expression plasmids]

OBJECTIVE

To construct the prokaryotic recombinant expression plasmids of Toxoplasma gondii GRA8 and analyze their expression in E. coli containing the prokaryotic recombinant plasmids.

METHODS

The full gene and its truncated fragment of GRA8 were amplified by PCR from T. gondii genomic DNA, and cloned into pMD18-T vector. The right genes in positive clones sequenced with ABI PRISMTM 377XL DNA Sequencer were digested with restrictive endonucleases and subcloned into pGEX-4T-2. The recombinant plasmids were transformed into E. coli JM109. The recombinant clones were characterized by PCR and digested with restriction endonucleases. Positive clones were induced with IPTG to express target protein and characterized by SDS-PAGE. The recombinant protein was purified from E. coli lysate by affinity chromatography and SDS-PAGE. The immunological activity of this protein was analyzed by Western blotting.

RESULTS

The gene fragments encoding GRA8 were amplified by PCR from T. gondii genomic DNA. The inserts of GRA8 in positive clones were coincident with the original sequence of GRA8 gene from GenBank. The recombinant expression plasmids were constructed through subcloning the right inserts of GRA8 into pGEX-4T-2. The expression level of GRA8 from the recombinant expression plasmids in E. coli was low, and there was almost no full-length GRA8 expressed in E. coli. The purified protein reacted with the sera from rabbits infected with T. gondii RH strain.

CONCLUSION

The expression level of GRA8 from the recombinant expression plasmids in E. coli is low and the purified truncated GRA8 shows certain antigenicity.

[Studies of the integration and expression of exogenes in transgenic rice obtained via particle bombardment transformation]

Various integration events from simple to complex have been found in transgenic elite rice varieties, which were co-transformed with bar and cecropin B gene by particle bombardment after system studies of the structure and expression of the transgene. It was displayed that there were one to seven insertion loci and one to ten copies of transgene in different transformants. No absolute correlation was found between the numbers of transgene copies and the gene expression. Different level expression of transgenes with similar insertion mode was also discovered. The expression cassette integrity and transcription frequency of selectable bar gene were more than non-selectable cecropin B gene, whereas gene silence in plants integrated with intact bar gene was found and higher expression level of cecropin B gene with 0.6 kb fragments degraded in terminator was deduced.

[Study on the relationship between nitric oxide and allergic rhinitis]

OBJECTIVE

To investigate the relationship between nitric oxide (NO) and allergic rhinitis (AR).

METHOD

NO in the serum of 50 patients with AR and 40 healty control were measured by nitrate reductase.

RESULT

The level of serum NO in AR group was higher than that in healthy control group (P < 0.001).

CONCLUSION

There is a relationship between the level of NO in serum and AR. The results suggest that the NO may play an important role in the pathogenesis of AR.