Surveillance and control strategy of imported schistosomiasis mansoni: an expert consensus / 中国血吸虫病防治杂志

In 1980s, Biomphalaria straminea, an intermediate host of Schistosoma mansoni, was found in Shenzhen City, Guangdong Province, China, and currently, this snail has colonized in Shenzhen City and spread to peripheral cities involving of Dongguan and Huizhou. Since imported cases infected with S. mamoni have been reported from time to time in China, Mainland China is facing the potential risk of transmission of schistosomiasis mansoni. With the deepening of the opening-up policy, notably the implementation of the Belt and Road Initiative, there is an increase in the risk of transmission of schistosomiasis mansoni in Mainland China. Increasing the understanding on schistosomiasis mansoni, improving the awareness toward schistosomiasis mansoni prevention and control, and identifying, reporting and managing imported cases with S. mansoni infection or pathogen carriers, are of particular importance to prevent the development of entire life cycle of S. mansoni and the resultant schistosomiasis mansoni transmission in China. To protect public health, a consensus has been reached pertaining to the surveillance and control strategy of imported schistosomiasis mansoni by Chinese infectious disease experts and parasitologists, with aims to improve the awareness and capability for the diagnosis, treatment and control of imported schistosomiasis mansoni among Chinese disease control and prevention institutions and medical institutions, and decrease and even eliminate the risk of schistosomiasis mansoni transmission in China.

Surveillance and control strategy of imported schistosomiasis mansoni: an expert consensus / 中国血吸虫病防治杂志

In 1980s, Biomphalaria straminea, an intermediate host of Schistosoma mansoni, was found in Shenzhen City, Guangdong Province, China, and currently, this snail has colonized in Shenzhen City and spread to peripheral cities involving of Dongguan and Huizhou. Since imported cases infected with S. mamoni have been reported from time to time in China, Mainland China is facing the potential risk of transmission of schistosomiasis mansoni. With the deepening of the opening-up policy, notably the implementation of the Belt and Road Initiative, there is an increase in the risk of transmission of schistosomiasis mansoni in Mainland China. Increasing the understanding on schistosomiasis mansoni, improving the awareness toward schistosomiasis mansoni prevention and control, and identifying, reporting and managing imported cases with S. mansoni infection or pathogen carriers, are of particular importance to prevent the development of entire life cycle of S. mansoni and the resultant schistosomiasis mansoni transmission in China. To protect public health, a consensus has been reached pertaining to the surveillance and control strategy of imported schistosomiasis mansoni by Chinese infectious disease experts and parasitologists, with aims to improve the awareness and capability for the diagnosis, treatment and control of imported schistosomiasis mansoni among Chinese disease control and prevention institutions and medical institutions, and decrease and even eliminate the risk of schistosomiasis mansoni transmission in China.

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.

Applicability of a sensitive duplex real-time PCR assay for identifying B/Yamagata and B/Victoria lineages of influenza virus / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To develop a novel sensitive duplex real-time PCR assay for accurately identifying B/Yamagata and B/Victoria lineages of influenza virus type B.</p><p><b>METHODS</b>50 HA (hemagglutinin) gene sequences coding for B/Yamagata and B/Victoria lineage, respectively, were randomly downloaded for GenBank and analyzed by software MEGA. Primers and probes specific for HA gene of B/Yamagata and B/Victoria lineages were designed by Primer Primer and then applied in the duplex real-time RT-PCR method that was followed developed. Influenza virus B type and A type isolated in our laboratory and typing-confirmed by HAI method were used as reference strains to determine the specificity of this assay and the sensitivity of the duplex amplification was evaluated by viral load testing in terms of in vitro transcribed RNA copy number.</p><p><b>RESULTS</b>In 2006-2010, 793 influenza virus type B strains were isolated from 17 765 throat swab samples, among which 152 strains were differentiated as By lineage and 641 as Bv lineage by this assay. These results was agreement with that determined by HAI assay. This developed assay allows to accurately identify approximately 10(2) copies/microl for Bv and By lineage virus with intra- and inter-coefficient of variation (CV) < 3.5% and nearly 100% specificity.</p><p><b>CONCLUSIONS</b>This method provides sensitive and robust tool for routine diagnosis and on-time epidemiological examination of influenza virus, which could be applied in influenza surveillance laboratories for rapid molecular diagnosis.</p>

Compare real-time RT-PCR with two culture methods for influenza virus detection / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Real-time RT-PCR, cell culture and embryonated eggs culture for influenza detection were compared by analyzing the data of influenza surveillance in Shenzhen in second half of 2009.</p><p><b>METHODS</b>1092 clinical samples (throat swabs) collected during second half of 2009 were tested by real-time RT-PCR, cell culture and embryonated eggs culture, and the results were analyzed by statistical methods.</p><p><b>RESULTS</b>The positive rate were 54.21%, 27.11% and 16.21% using real-time RT-PCR, cell culture and embryonated eggs culture, and the sensitive were 100%, 50% and 29.9%. The lowest dilutions of virus detected by real-time RT-PCR were 10(-2) TCID50/ml.</p><p><b>CONCLUSION</b>The sensitive of real-time RT-PCR was higher than culture and the specificity was also very high. It was more suitable for emergency detect. The sensitive of cell culture for H3N2 subtype was higher, and sensitive of embryonated eggs culture for type B was higher.</p>

Detection of circulating antigen of Angiostrongylus cantonensis by 12D5 and 21B7 monoclonal antibodies / 中华流行病学杂志

Objective To detect the rate of Angiostrongylus cantonensis infection and to study the effects of treatment so as to prepare monoclonal antibodies (McAbs) ,and gold immunochroma-tography assay (GICA) with 12D5 and 21B7 McAbs could be prepared in advance. Methods Two McAbs (12D5 and 21B7) were applied to detect the circulating antigen (CAg) in the sera of rats infected with A. cantonensis and angiostrongyliasis patients respectively by double antibody sandwich ELISA. Either 12D5 or 21B7 McAbs was used as antibody and protein A was conjugated with colloid gold as the detection marker. A special pad for GICA was designed according to the reaction procedure, and CAg were detected by GICA in the sera of rats infected with A. cantonensis and angiostrongyliasis patients respectively. Results 12D5 McAb was identified as IgG1 and 21B7 McAb was IgM. Results from Western blotting showed that two McAbs could be used to identified 55 KD protein of adult worms of A. cantonensis. The detection rates of CAg in the sera of infected rats was 100% (48/48) and the detection rates of CAg in the sera of angiostrongyliasis patients was 100% (32/32). No cross-reaction to sera of patients with other infection of parasites, such as clonochiasis, fasiolopsiasis, ancylostotniasis, ancylostomiasis, anisakiasis as well as schsitosomiasis wee seen and normal sera did not react with 12D5 and 21B7 McAbs. Conclusion Results from sandwich ELISA and GICA with 12D5 and 21B7 McAbs showed high specificity and acting as detecting CAg of A. cantonensis in sera of infected animals and patients. We noticed that GICA with 12D5 and 21B7 was not only rapid and simple that without requirement of special instrument, but also rather sensitive and specific for the detection of current infection with A.cantonensis.

Analyses of serological and genetic characteristics on novel H1N1 influenza A virus from the infected patient in Shenzhen / 病毒学报

Analysis of serological and genetic characteristics on 2009 swine-origin influenza A (H1N1) virus (S-OIV) isolated from four patients with severe disease in Shenzhen were performed. Microneutralization assay showed that the neutralizing antibody titers of the infected patients did not exceed 1 : 20 in a short term post infection, which could not neutralize the viruses efficiently. Hemagglutination inhibition (HI) tests confirmed that the antigenicity of S-OIV from the patients was distinct from the seasonal influenza A virus, but similar to the reference strains of S-OIV. Phylogenetic and molecular analysis showed that S-OIV from the patients still belonged to the classical swine lineages and did not have the genetic characteristics of highly pathogenic influenza virus. Several amino acid residue mutations on HA protein were detected, which seemed not to affect the virulence and pathogenicity of the viruses. Further, A His 275 Tyr mutation on NA protein of a virus strain was detected, which induced the oseltamivir resistance of the virus.

Study on the relationship between polymorphism of adiponectin gene and risk of ischemic stroke among Han population in the Northern parts of China / 中华流行病学杂志

Objective To explore the association between polymorphisms of adiponectin gene and the risk of ischemic stroke in Han population from the Northern parts of China.Methods TaqMan probe of RT-PCR was applied to detect the genotype frequency of single nucleotide polymorphism(SNPs)(rs266729 and rs2241766)of adiponectin gene in 357 ischemic stroke cases who developed the episode at first time and with 345 healthy controls.Logistic regression analysis was used to evaluate the relationship of each genotype of SNPs and ischemic stroke.Results Mutation of rs2241766(T＞G)increased the risk of ischemic stroke among all the samples(0R=1.55,P=0.01)and it was still the risk factor of ischemic stroke when analyzed by multi-factors logistic regression after each factor was adjusted(OR=1.55,P=0.00).The polymorphism of rs266729 was not related to the risk of ischemic stroke among all the samples(OR=1.13,P=0.57).However,the genotype GG of rs266729 increased the risk of ischemic stroke among female population(OR=3.25,P=0.04).Conclusion The variance of rs2241766 in adiponectin gene was related to the risk of ischemic stroke in Han population from the Northern parts of China and the genotype GG of rs266729 could possibly increase the risk of ischemic stroke in women of Han population from the Northern parts of the country.

siRNAs targetting sphingomyelin phosphodiesterase 1 protect mouse oocytes from apoptosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the potential of siRNAs targeting sphingomyelin phosphodiesterase 1 (SMPD1) in protecting the oocytes from apoptosis, and explore new approaches to female fertility preservation.</p><p><b>METHODS</b>Chemically synthesized siRNA targeting SMPD1 were introduced into mouse oocytes retrieved by hyperstimulation, and the cell apoptosis was analyzed by comic assay 48 and 72 h later.</p><p><b>RESULTS</b>In the oocytes without any siRNA injection, oocyte DNA damage occurred after 24 h, and large amount of DNA fragments migrated from the cells 48 h later. In oocytes injected with siRNA003, DNA migration decreased significantly as compared with the control and the other two groups injected with siRNA001 and siRNA002 (P<0.01).</p><p><b>CONCLUSION</b>siRNA targeting SMPD1 may protect the oocytes from apoptosis, and has the potential for use in future female fertility preservation.</p>

Molecular epidemiological study on oxidative DNA damage among Hasake ethnic migrants in Shenzhen / 中华流行病学杂志

objective To explore the relationship of migration and oxidative DNA damage by comparative study of oxidative DNA damage effects on people with difierent years of migration among Xinjiang Hasake ethnecity in Shenzhen.Methods Sixty Hasake residents in Shenzhen were selected,and were divided into three groups(n=20)according to the years of migration.Major changes of their life style were investigated.8-hydroxy-2'-deoxyguanosine(8-OH-dG)levels in urine were analyzed,and comet assay of peripheral blood lymphocytes conducted.Results When comparing with the group having a shorter than 1 year of stay,a significant decrease of oliveive tail moment and tail/head length in comet assay in the＞3 years group(P＜0.05)was observed 8-OH-dG level decreased significantly in 1-3 years group (P＜0.05)and＞3 years group(P＜0.01).Conclusion Our results suggested that life style changes which related to migration might reduce DNA damage in Hasake nationalities.

Study on the epidemiological characteristics and natural infectious focus of Angiostrongylus cantonensis in Shenzhen area of Zhujiang Delta in China / 中华流行病学杂志

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 angiostrongliasis in Shenzhen area.

Induced differentiation and signaling factor PTEN expression of 3T3-L1 adipocytes / 南方医科大学学报

<p><b>OBJECTIVE</b>To optimize the condition for inducing the differentiation of 3T3-L1 preadipocytes into adipocytes and study the expression of PTEN tumor suppression gene in this process, aiming to understand the regulatory role of PTEN in normal adipocyte differentiation and collect laboratory evidence for developing drugs targeting PTEN.</p><p><b>METHODS</b>The differentiation of 3T3-L1 preadipocytes cultured in high-glucose DMEM were induced according to 2 protocols with different combinations of dexamethasone, isobutylmethylxanthine (IBMX) and insulin, and the resultant adipocytes were identified by oil red O staining. The total proteins of 3T3-L1 were extracted and analyzed by Western blotting, and PTEN homology between mice and human was analyzed by bioinformatic method.</p><p><b>RESULTS</b>For optimized 3T3-L1 differentiation, 3T3-L1 cells were initially induced with the combination of 1 micromol/L dexamethasone, 0.5 mmol/L IBMX and 5 microg/ml insulin for 48 h, followed by treatment with 5 microg/ml insulin in 4.5 g/L glucose DMEM for 48 h, which resulted in high differentiation rate of 3T3-L1 cells (up to 90% on the 10th day) with unified morphology and size. PTEN expression varied quantitatively in the process of differentiation, especially low on the 12th day as compared with those measured on days 4, 6 and 9. The mice PTEN mRNA shared 96% homology and PTEN amino acid 100% homology with their human counterparts.</p><p><b>CONCLUSION</b>Endogenous PTEN expression is down-regulated during 3T3-L1 differentiation, suggesting that PTEN may enhance insulin sensitivity and promote adipogenesis under physiological conditions.</p>

Epidemiological studies on Clonorchis sinensis infection along the Zhujiang River in Lou village of Shenzhen / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the transmission route and epidemiological features of Clonorchis sinensis infection in Shenzhen area--the biggest immigration city of Southern China.</p><p><b>METHODS</b>In this study, we examined 1473 individuals (710 males and 763 females) to determine the current status of C. sinensis infection among the people in one village in Zhujiang river region, Guangdong province, China. Blood samples were detected on antibody of C. sinensis with enzyme linked immunosorbent assay,and stool specimens from sera positive cases were examined by modified Kato-Katz thick smear to confirm the density of infection. People were interviewed on their life styles under the structured questionnaire which was administered by trained staff members. Major content of the questionnaire included eating raw fish, using the same utensils for both raw fish and cooked food, using feces of domestic animals and human feces to feed fish and so on.</p><p><b>RESULTS</b>Among 1473 people examined, 70 (4.75%) were found infected with C. sinensis. By counting eggs per gram feces (EPG), it was found that heavy intensities of infection in males was stronger than that of females,and the overall average EPG was 41.87. Of 1473 interviewees, 54% of them did not know about fluke disease or its transmission route, 12% of those who knew about the fluke but believed that the infection caused no harm or only slight harm to their health. 27% of the interviewees ate raw fish at least 1-2 times per months with 5% of the families using the same utensils for both raw fish and cooked food. 40% of the fish ponds owners fed their fish with the feces of domestic animals and human feces.</p><p><b>CONCLUSION</b>Together with these results, unhealthy behaviors, poor knowledge, inappropriate farming/fishery practices, eating raw fish were important factors influencing the C. sinensis prevalence in humans.</p>