Molecular identification of Tricula spp. and the parasitized trematode cercariae in schistosomiasis-endemic areas of Yunnan Province / 中国血吸虫病防治杂志

Objective To characterize a species of the genus Tricula and parasitized trematodes in schistosomiasis-endemic areas of Yunnan Province using a molecular analysis, so as to understand their taxonomic positions. Methods Tricula spp. and Oncomelania snails were collected from Xiangyun County, Yunnan Province, and cercaria parasitizing snails were observed using crushing followed by microscopy. Cercaria parasitizing Tricula snails at various morphologies were sampled using a shedding method. Genomic DNA was extracted from snail soft tissues and cercariae, and the 16S rRNA, COI, 28S rDNA genes in snails and the ND1 and 28S rDNA genes in cercariae were amplified using a PCR assay and sequenced. The species of Tricula snails and their parasitized trematodes was characterized using sequence alignment and phylogenetic analysis. Results Among 382 Tricula snails detected, there were three types of trematode cercariae found, including the non-forked (20.94%, 80/382), double-forked (3.40%, 13/382) and swallow shapes (7.07%, 27/382). Sequence and phylogenetic analyses showed that the 16S rRNA, COI and 28S rDNA gene sequences of this species of Tricula had high homology to those in Delavaya dianchiensis, and were clustered in a branch. Sequencing analysis of the ND1 and 28S rDNA genes revealed that the non-forked cercariae belonged to the family Pleu- rogenidae, the swallow-shaped cercariae belonged to the family Opecoelidae, and the double-forked cercariae belonged to another species of the genus Schistosoma that was different from S. sinensium and S. ovuncatum. Conclusion The species and taxonomy of Triculla spp. and their parasitized trematodes are preliminarily determined in schistosomiasis-endemic areas of Yunnan Province; however, further studies are required to investigate the more definite taxonomy and pathogenicity.

Morphology and Molecular Phylogeny of Raillietina spp. (Cestoda: Cyclophyllidea: Davaineidae) from Domestic Chickens in Thailand

Raillietina species are prevalent in domestic chickens (Gallus gallus domesticus) in Phayao province, northern Thailand. Their infection may cause disease and death, which affects the public health and economic situation in chicken farms. The identification of Raillietina has been based on morphology and molecular analysis. In this study, morphological observations using light (LM) and scanning electron microscopies (SEM) coupled with molecular analysis of the internal transcribed spacer 2 (ITS2) region and the nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) gene were employed for precise identification and phylogenetic relationship studies of Raillietina spp. Four Raillietina species, including R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp., were recovered in domestic chickens from 4 districts in Phayao province, Thailand. LM and SEM observations revealed differences in the morphology of the scolex, position of the genital pore, number of eggs per egg capsule, and rostellar opening surface structures in all 4 species. Phylogenetic relationships were found among the phylogenetic trees obtained by the maximum likelihood and distance-based neighbor-joining methods. ITS2 and ND1 sequence data recorded from Raillietina sp. appeared to be monophyletic. The query sequences of R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp. were separated according to the different morphological characters. This study confirmed that morphological studies combined with molecular analyses can differentiate related species within the genus Raillietina in Thailand.

Prevalence, Associated Risk Factors, and Phylogenetic Analysis of Toxocara vitulorum Infection in Yaks on the Qinghai Tibetan Plateau, China

Toxocara vitulorum has been rarely reported in yaks at high altitudes and remote areas of Sichuan Province of Tibetan Plateau of China. The current study was designed to investigate the prevalence, associated risk factors, and phylogenetic characteristics of T. vitulorum in yak calves on the Qinghai Tibetan plateau. Fecal samples were collected from 891 yak calves and were examined for the presence of T. vitulorum eggs by the McMaster technique. A multivariable logistic regression model was employed to explore variables potentially associated with exposure to T. vitulorum infection. T. vitulorum specimens were collected from the feces of yaks in Hongyuan of Sichuan Province, China. DNA was extracted from ascaris. After PCR amplification, the sequencing of ND1 gene was carried out and phylogenetic analyses was performed by MEGA 6.0 software. The results showed that 64 (20.1%; 95% CI 15.8–24.9%), 75 (17.2; 13.8–21.1), 29 (40.9; 29.3–53.2), and 5 (7.6; 2.5–16.8) yak calves were detected out to excrete T. vitulorum eggs in yak calve feces in Qinghai, Tibet, Sichuan, and Gansu, respectively. The present study revealed that high infection and mortality by T. vitulorum is wildly spread on the Qinghai Tibetan plateau, China by fecal examination. Geographical origin, ages, and fecal consistencies are the risk factors associated with T. vitulorum prevalence by logistic regression analysis. Molecular detection and phylogenetic analysis of ND1 gene of T. vitulorum indicated that T. vitulorum in the yak calves on the Qinghai Tibetan plateau are homologous to preveiously studies reported.

Loop-mediated isothermal amplification for rapid detection of dogs infected with Echinococcus species based on copro-DNAⅡ / 中国人兽共患病学报

To control and prevent the Echinococcus in the place ,we established a loop-mediated isothermal amplification (LAMP) assay for rapid detection of Echinococcus species specific DNA from dog faeces .Four primers which recognizing 6 dis-tinct regions on the NADH dehydrogenase subunit 2 (ND2) gene of Echinococcus granulosus were designed and used for LAMP assay .The specificity of LAMP assay was evaluated using DNA extracted from Echinococcus granulosus , Taenia saginata , and other dog intestinal parasites .In addition ,the sensitivity of LAMP assay was compared with that of conventional PCR using recombinant plasmid carrying Echinococcus granulosus ND2 gene fragment as standard template DNA after 10-fold serial dilution .Furthermore ,we extracted DNA from 46 canine fecal samples collected from endemic areas ,and tested the copro-DNA samples using LAMP and necropsy method .Results showed that E .g ND2 primer sets could differentiate Echinococcus granulosus from Echinococcus multilocularis without cross reaction among other parasites detected .Furthermore ,the LAMP assay with primer sets to the ND2 gene could detect 4 × 101 copies of target gene ,demonstrating 103 times higher sensitivity than that of conventional PCR methods .The LAMP assay with primer set to ND2 gene showed good sensitivity and specificity to detect copro-DNA samples extracted from fecal samples of 46 dogs tested in endemic areas .There was no statistically signifi-cant difference among LAMP and necropsy .In this study ,a sensitive ,specific and rapid copro-DNA detection LAMP assay was developed successfully for diagnosis of dogs infected with Echinococcus granulosus .Due to its rapidity ,simplicity ,speci-ficity and sensitivity ,the LAMP assay is a promising new tool for rapid detection of dogs infected with Echinococcus spp .dur-ing the field survey or in poor-equipped laboratories .

Gene sequence analysis on CO1 and ND1 of Echinococcus g ranulosus / 中国人兽共患病学报

The purpose of this study was to clarify the strains of E .granulosus from sheep of Xiwuqi and people of Xil-inhot in Inner Mongolia region and its genotypes .CO1 and ND1 of mitochondria gene were cloned and sequenced ,and then they were analyzed by MegAlign of DNAStar5 .0 .Results showed that the length of CO1 and ND1 gene of E .granulosus ,which were from sheep of Xiwuqi or people of Xilinhot ,were 936 bp and 895 bp ,respectively .The homology of CO1 gene sequences of E .granulosus strains from Xiwuqi and Xinjiang was 99 .3% ,while the homology of the corresponding gene sequences of E .granulosus from man of Xilinhot City and Xinjiang were 98 .6% .ND1 gene of E .granulosus of sheep from Xiwuqi and hu-man from Xilinhot were identical to ND1 gene of G1 type .All these indicated that the homology of E .granulosus from the two regions were high and the genotype were G1 type ,which provided an important basis for the determination of strains ,and it al-so had a great significance to prevent and control the disease .

Mutation frequency analysis of mitochondrial ND1 gene associated with Leber hereditary optic neuropathy in Chinese population / 中华实验眼科杂志

Background Leber hereditary optic neuropathy (LHON)is a common inherited eye disease,which generally affects young adults with bilateral loss of central vision.Mutation frequency of Leber hereditary has not been fully clarified. Objective This study was to investigate the mutation frequency of mitochondrial NDI gene associated with LHON in Chinese population. Methods The proposal of the study was approved by Ethic Committee of Wenzhou Medical College.Written informed consent was obtained from each subject initial of this trial.Eight hundred and ninety-four LHON patients and 134 normal subjects were collected.Genomic DNA was extracted from peripheral blood leukocytes of the all participants.Polymerase chain reaction (PCR) was used to amplify and sequence analysis of the mitochondrial ND1 gene was performed and aligned with revised Cambridge Reference Sequence(rCRS) of mitochondrial DNA.Then mutated gene frequency was screened and analyzed. Results Mutational analysis of mitochondrial ND1 gene in 894 LHON patients revealed the presence of G3316A,T3394C,G3460A,C3497T,G3635A,G3733A,and T4216C.11.19％ LHON patients (100/894 ) were found to be associated with the gene mutations mentioned above,and 3.24％ patients (29/894) showed the co-occurrence of three primary mutations.Mutation frequencies in LHON patients were 2.57％,2.23％,1.45％,3.80％,0.67％,0.11％,0.34％,respectively,and G3316A,T3394C,C3497T and T4216C also were detected in 134 normal controls with the mutation frequencies of 4.48％,2.99％,4.48％ and 1.49％,respectively.Mutation frequency analysis showed an insignificant difference in the mutations of G3316A,T3394C,C3497T and T4216C between LHON patients and normal controls (x2 =0.926,P=0.336;x2 =0.052,P=0.820; x2 =0.142,P=0.707;P=0.129).G3376A,G3496T,G3700A,A4136G,T4160C and C4171A were absent in Chinese LHON patients. Conclusions Mitoehondrial ND1 gene in LHON is a mutational hotspot in Chinese population,11.19％ (100/894)associated with LHON was caused by ND1 gene mutation.G3635A,G3733A may be rare pathological mutation in Chinese population.However,G3316A,T3394C,C3497T and T4216C are insufficient to produce the clinical phenotype,but they may play a synergic role for penetrance and phenotypic manifestation in LHON.

Correlation analysis of polymorphisms in mtDNA 3243, 3316, 3394 point mutation with schizophrenia / 第二军医大学学报

Objective: To study the effects of mitochondrial DNA (mtDNA) point mutations 3243A/G, 3316G/A, and 3394T/C on the incidence of schizophrenia (SZ) in the Han nationality in Henan province. Methods A total of 250 unrelated patients and 292 normal controls without family history of schizophrenia were included in the present study, and their peripheral blood samples were subjected to examination by PCR, digestion with different restriction enzymes, agarose gel electrophoresis, and DNA sequencing to detect the mutations of mtDNA 3243, 3316, and 3394. Statistical analysis was performed by SPSS17. 0 statistic software. Results: mtDNA 3316 G/A mutation was found in 8 SZ patients and in 3 controls (P>0. 05). mtDNA 3394 mutation was found in 15 SZ patients and 4 controls, with significant difference between the two groups (P<0. 05). No mtDNA 3243 mutation was found in the two groups. Conclusion: The findings in the present study indicate that mutation of mtDNA 3394T/C may be related to SZ, and the mutation of mtDNA 3243A/G and 3316G/A may not be related to SZ.

Study on Molecular Phylogeny of Schistosoma sinensium Based on Mitochondrial Genes / 中国寄生虫学与寄生虫病杂志

Objective To determine the phylogenetic position of Schistosoma sinensium in the genus Schistosoma using mitochondrial cytochrome C oxidase 1 (CO1) and NADH dehydrogenase 1(ND1) as molecular markers. Methods The genomic DNA of adult worms were extracted by the GNT\|K method. The target regions were amplified by PCR using specific primers. The PCR products were purified before ligation into the plasmid Zero\|Blunt. Recombinant plasmids were amplified in E.coli, extracted and purified using routine methods and then sequenced using M13 primers (F/R) on a Licor long\|read auto\|sequencer. Sequences of related schistosomes were retrieved from GenBank and aligned with our data in the sequence editor ESEE. Gene trees were constructed in PHYLIP and MEGA using both maximum parsimony and neighbor\|joining methods. For parsimony analysis, all characters were treated as unordered and with equal weights. At least \{3 000\} cycles of bootstrapping were carried out. For analysis in MEGA, all gap columns were deleted. The third position of codon was included. Results The nucleotide and amino acid sequences of CO1 and ND1 of S.sinensium were obtained. Conclusion The phylogenetic trees from these molecular data suggested that S.sinensium belongs to the Asian schistosome group, and the results coincided with the previous rDNA (ITS2 & LSU) analysis results.