Population genetic quality analysis of 3 subbreeds of China Agricultural University miniature pigs in Beijing / 中国比较医学杂志

Objective To analyze and evaluate the population genetic quality of 3 subbreeds of China Agricultural University miniature pigs in Beijing.Method According to the local standard DB11/T828.3 -2011, 25 pairs of microsatellite primers were used in 3 subbreeds of China Agricultural University miniature pigs, and software Popgen32 was used to process the data.Results 24 microsatellite loci shared 130, 122 and 138 alleles in the China Agricultural University miniature pigs I, II, III, respectively. The average heterozygosity was 0.6759, 0.5967 and 0.6779, respectively, while the average polymorphism information content ( PIC) was 0.6344, 0.5540 and 0.6403, respectively. The genetic distance between China Agricultural University miniature pig II and III was 0.4251, while the genetic distance between China Agricultural University miniature pig I and II was 0.2084.Conclusions In the 3 subbreeds, China Agricultural University miniature pigs II and III have genetic stability and genetic diversity, and both of which satisfy with the genetic characteristics of closed colony laboratory animal.

Prevalence and molecular identification of Syphacia muris in laboratory animals in China / 中国比较医学杂志

Objective To acquire the prevalence and molecular identification data on Syphacia muris and provide reference for the revision of national standard. Methods 923 batches of 5199 SPF animals ( including one batch of 5 monkeys, 3 batches of 25 mini?pigs, 28 batches of 55 rabbits, 13 batches of 248 hamsters, 37 batches of 198 guinea pigs, 93 batches of 459 rats, 742 batches of 4179 mice, 5 batches of 25 chickens and one batch of 5 ducks) and 145 batches of 1389 clean animals ( including one batch of 3 rabbits, 4 batches of 31 hamsters, 16 batches of 157 guinea pigs, 32 batches of 268 rats and 92 batches of 930 mice ) came from 50 different manufactures in China. Direct microscopy real?time dynamic video recording techniques in combination with morphological identification method were applied to screen the Syphacia muris infestation. A multiple polymerase chain reaction ( multiple?PCR ) testing of the isolate based on amplification of the conserved portions of the Syphacia muris internal transcribed spacer (ITS), 28S ribosomal RNA (28S rRNA), NADH dehydrogenase subunits 1 (nad1) and cytochrome c oxidase subunit 1 (cox1) genes, and the molecular sequencing of the multiple?PCR amplicons was used to confirm the Syphacia muris infection. Results Syphacia muris eggs, larvae and adults were detected by using direct microscopy real?time dynamic video recording technique. Syphacia muris were detected based on the morphology and size of ovum, larvae, and female and male adult worms. Multiple?PCR and sequencing were performed to identify ITS, 28S rRNA, nad1 and cox1 genes of DNA extracted from the single egg, larva and adult parasite Syphacia muris. This approach allowed the specific identification with no amplicon being amplified from heterogeneous DNA samples, and sequencing confirmed the identity of the amplified sequences. Molecular characterization by multiple?PCR amplification and sequencing of the ITS, 28S rRNA, nad1 and cox1 genes demonstrated the presence of Syphacia muris. Multiple?PCR followed by sequencing confirmed 285 of 5199 SPF and 135 of 1389 clean animal samples classified as positive by using direct microscopy real?time dynamic video recording technique in the study as containing Syphacia muris?specific DNA. Comparison of the partial sequences of the ITS, 28S rRNA, nad1 and cox1 genes revealed 100% similarity amongst Syphacia muris from different animals. The prevalence of Syphacia muris infection in SPF and clean animals were 5?5% (285/5199) and 9?7% (135/1389), respectively. Conclusions Direct microscopy real?time dynamic video recording technique, multiple?PCR and sequencing can be used to rapidly detect and accurately identify Syphacia muris. The zoonotic nature of Syphacia muris can be regard as a public health alter, hence the good quality control of animal has an important role in protecting human health and safeguarding people safety. This is the first molecular identification and infection investigation of Syphacia muris in SPF and clean animals in China.

Diagnoses of Giardia lamblia / 中国比较医学杂志

Objective Giardia lamblia is an important pathogen of zoonosis giardiasis , it poses a potential threat to the quality of SPF (specific pathogen-free) laboratory animals cannot be ignored.The aim of this study is to establish the method of rapid diagnosis of Giardia lamblia, and analyze the test results of 516 batches form 17 manufactures.Methods Direct microscopy, Giemsa-fast staining and multiplex polymerase chain reaction (multiplex PCR) were applied to detect Giardia lamblia.Results Numerous of Giardia lamblia trophozoites and cysts were detected in SPF laboratory animals by using direct microscopy and Giemsa-fast staining, and multiplex PCR were performed to identify 18S rDNA,β-giardin, TPI and GDH genes of DNA extracted from these trophozoites and cysts identified Giardia lamblia.Direct microscopy, Giemsa-fast staining, and multiplex PCR methods can be used to detect Giardia lamblia.Of the 2562 SPF laboratory animals studied, 22.9%(586/2562) were positive for Giardia lamblia.Conclusions Direct microscopy , Giemsa-fast staining , and multiplex PCR were effective techniques with high sensitivity and specificity for rapid diagnosis of Giardia lambliain.It is not satisfactory that the results of Giardia lamblia examination in 516 batches form 17 manufactures failed to meet the requirements 100%.

Pathogenic and molecular diagnoses of Strongyloides stercoralis infection in tumor transplanted nude mice / 中国比较医学杂志

Objective To diagnosis tumor transplanted nude mice Strongyloidiasis .Methods Postmortem microscopic examination of the tumor transplanted nude mice detected Strongyloides stercoralis for morphological identification and double polymerase chain reaction ( PCR ) assay for molecular diagnosis of Strongyloides stercoralis infection in tumor transplanted nude mice .Results Presence of numerous S .stercoralis in autopsy in tumor transplanted nude mice samples preliminary determined the diagnosis of strongyloidiasis .Confirmed diagnosis of Strongyloides stercoralis infection by double PCR detection of specific DNA in tumor transplanted nude mice samples .Conclusion The most important clue to prevent such serious consequences is early diagnosis .Tumor transplanted recipients and donors should be screened for parasitic infections including strongyloidiasis .To the authors ’ knowledge , this study is the first extensive report on diagnosis tumor transplanted nude mice Strongyloidiasis .

Diversity of fungi derived from the Cricetulus migratorius from the Xinjiang region of China / 中国人兽共患病学报

To monitor and analyze Cricetulus migratorius fungal diversity ,60 adult Cricetulus migratorius brought from Xinjiang region of China were dissected after being euthanized and the specimens were collected .Fungal diversity research was carried out by TaqMan MGB probe real-time fluorescence quantitative PCR ,the ribosome cloning sequencing ,and fungal cul-ture identification techniques .The 60 fungal isolates were characterized from Cricetulus migratorius ,including Candida albi-cans ,Trichosporonasahii ,Aspergillus fumigatus ,Aspergillusniger ,Aspergillussydowii ,Aspergillus japonicus ,Asper-gillus ustus ,Aspergillus versicolor ,Penicillium chrysogenum ,Paecilomyces variotii ,Penicillium aurantiogriseum ,Neuros-pora sitophila ,Neurospora intermedia ,and Cladosporium cladosporioides .Many of them associated with grey hamster as zoonotic pathogens .The results showed that the most dominant fungal group was Aspergillus ,and Penicillium followed by it . These fungi were susceptible to nystatin ,clotrimazole and voriconazole .It’s indicated that application of TaqMan MGB probe real-time fluorescence quantitative PCR ,the ribosome cloning sequencing ,and fungal culture identification techniques could ef-fectively analyze Cricetulus migratorius .The results could provide a scientific basis for Cricetulus migratorius microbiological monitoring and quality standard establishment in China .Overall ,the findings of the present study constitute ,to the authors’ knowledge ,the first extensive report on the diversity of fungal flora associated with Cricetulus migratorius .

Develonment and application of TaqMan MGB probe real-time fluorescence quantitative PCR for rapid detection of Helicobacter hepaticus / 中华微生物学和免疫学杂志

Objective To develop a TaqMan MGB probe-based,sensitive and specific real-time fluorescence quantitative PCR assay for rapid detection of Helicobacter hepaticus.Methods Primers and probes specific toflaB gene of Helicobacter hepaticus were designed.A TaqMan MGB probe-based,real-time fluorescence quantitative PCR was established.The specificity,sensitivity and stability of the assay were assassed.Then,the established TaqMan MGB probe real-time fluorescence quantitative PCR assay was applied to detect Helicobacter hepaticus in 1081 clinical specimens during 2008-2011,compared with bacterial isolation and culture method and conventional PCR assay.Results The specificity of this established TaqMan MGB probe-based real-time fluorescence quantitative PCR was high and there were no cross-reactivity with Helicobacter pylori,Campylobacter jejuni,Clostridium piliforme,Pasteurella pneumotropica,Escherichia coli,Pseudomonas aeruginosa.The detection limits was 8.3 copies.The correlation coefficient and slope value of standard curve were 0.999 and -3.227,respectively and the efficiency of TaqMan MGB-based probe realtime fluorescence quantitative PCR assay was 100％.The TaqMan MGB-based probe real-time fluorescence quantitative PCR and conventional PCR were preformed to detect Helicobacter hepaticus in 1081 clinical specimens,a total of 86 specimens were positive for Helicobacter hepaticus.However,there was only 4 specimens were positive by bacteria isolation and culture method.The results showed that TaqMan MGB -based probe real-time fluorescence quantitative PCR for Helicobacter hepaticas was more sensitive than bacteria isolation and culture method,and it could detect Helicobacter hepaticus DNA from clinical specimens directly,and detection time is only 2 hours.Conclusion The TaqMan MGB-based probe real-time fluorescence quantitative PCR assay was a reliable,specific,sensitive and useful tool for rapid detection of Helicobacter hepaticus.

Identification and susceptibility test of bacteria isolated from miniature pigs in China / 中国人兽共患病学报

To investigate the prevalence and the antibiotic resistance of bacteria isolated from 25 miniature pigs. 45 bacterial strains were isolated, which were identified by biochemical assays, amplification of 16S rRNA genes by PCR and sequence analysis, and were evaluated for resistance to 30 antibiotics. The identification results showed that these bacteria belonged to Campylobacter (Campylobacter jejuni), Helicobacterium (Helicobacter pylori), Klebsiella (Klebsiella pneumoniae), Escherichia (Escherichia coli, Escherichia fergusonii), Pseudomonas (Pseudomonas aeruginosa), Stenotrophomonas (Stenotrophomonas maltophilia), Staphylococcus (Staphylococcus aureus, Staphylococcus haemolyticus, Staphylococcus simulans), Streptococcus (Streptococcus pneumoniae, Streptococcus suis, Streptococcus vestibularis, Streptococcus mitis, Gemella measles, Aerococcus viridans) and Bacillus (Bacillus subtilis, Bacillus licheniformis, Bacillus alvei, Bacterium megaterium). These bacteria were all susceptible to aztreonam and cephalothin. However, the resistence to furazolidone was found. Microbial population carried by miniature pigs in China had characters of diversity. Results of this study provided scientifical accordance for the microorganism monitoring of miniature pigs in China.

Expression of ORF_2 protein from hepatitis E virus in 293 cell / 临床检验杂志

Objective To study the immunoreaction of the recombinant proteins encoded by the fragments of ORF2 ( second open reading frames) gene of hepatitis E virus ( HEV). Methods The aimed sequence from the full-length ORF2 in clone PEH2 , which was derived from a Chinese strain of HEV,was amplified and cloned it into vector pcDNAS. 1 which was then transfected to 293 cell. Results The ORF2 protein was present in the soluble fractions of the cell lysate. The expressed protein of HEV ORF2 in 293 cells by using a plasmid pcDNA3. 1-based system showed positive on immunoblots probed against antibodies raised in BALB/c mice. Conclusion The experimental results laid a foundation for developing diagnostic reagent to detect HEV by using the expressed products of ORF2 protein.