Chitinase AO-801 is a hydrolase secreted by Arthrobotrys oligospora during nematode feeding, while its role remained elusive. This study analyzed the molecular characteristics of recombinant chitinase of Arthrobotrys oligospora (reAO-801). AO-801 belongs to the typical glycoside hydrolase 18 family with conserved chitinase sequence and tertiary structure of (α/β)8 triose-phosphate isomerase (TIM) barrel. The molecular weight of reAO-801 was 42 kDa. reAO-801 effectively degraded colloidal and powdered chitin, egg lysate, and stage I larval lysate of Caenorhabditis elegans. The activity of reAO-801 reached its peak at 40˚C and pH values between 4-7. Enzyme activity was inhibited by Zn2+, Ca2+, and Fe3+, whereas Mg2+ and K+ potentiated its activity. In addition, urea, sodium dodecyl sulfate, and 2-mercaptoethanol significantly inhibited enzyme activity. reAO-801 showed complete nematicidal activity against C. elegans stage I larvae. reAO-801 broke down the C. elegans egg shells, causing them to die or die prematurely by hatching the eggs. It also invoked degradation of Haemonchus contortus eggs, resulting in apparent changes in the morphological structure. This study demonstrated the cytotoxic effect of reAO-801, which laid the foundation for further dissecting the mechanism of nematode infestation by A. oligospora.

Cystatin, a cysteine protease inhibitor found in many parasites, plays important roles in immune evasion. This study analyzed the molecular characteristics of a cystatin from Fasciola hepatica (FhCystatin) and expressed recombinant FhCystatin (rFhcystatin) to investigate the immune modulatory effects on lipopolysaccharide-induced proliferation, migration, cytokine secretion, nitric oxide (NO) production, and apoptosis in mouse macrophages. The FhCystatin gene encoded 116 amino acids and contained a conserved cystatin-like domain. rFhCystatin significantly inhibited the activity of cathepsin B. rFhCystatin bound to the surface of mouse RAW264.7 cells, significantly inhibited cell proliferation and promoted apoptosis. Moreover, rFhCystatin inhibited the expression of cellular nitric oxide, interleukin-6, and tumor necrosis factor-α, and promoted the expression of transforming growth factor-β and interleukin-10. These results showed that FhCystatin played an important role in regulating the activity of mouse macrophages. Our findings provide new insights into mechanisms underlying the immune evasion and contribute to the exploration of potential targets for the development of new drug to control F. hepatica infection.

Background: Bovine papillomatosis is a type of proliferative tumor disease of skin and mucosae caused by bovine papillomavirus (BPV). As a transboundary and emerging disease in cattle, it poses a potential threat to the dairy industry. Objectives: The aim of this study is to detect and clarify the genetic diversity of BPV circulating in dairy cows in Xinjiang, China. Methods: 122 papilloma skin lesions from 8 intensive dairy farms located in different regions of Xinjiang, China were detected by polymerase chain reaction. The genetic evolution relationships of various types of BPVs were analyzed by examining this phylogenetic tree. Results: Ten genotypes of BPV (BPV1, BPV2, BPV3, BPV6, BPV7, BPV8, BPV10, BPV11, BPV13, and BPV14) were detected and identified in dairy cows. These were the first reported detections of BPV13 and BPV14 in Xinjiang, Mixed infections were detected, and there were geographical differences in the distribution of the BPV genotypes. Notably, the BPV infection rate among young cattle (< 1-year-old) developed from the same supply of frozen sperm was higher than that of the other young cows naturally raised under the same environmental conditions. Conclusions Genotyping based on the L1 gene of BPV showed that BPVs circulating in Xinjiang China displayed substantial genetic diversity. This study provided valuable data at the molecular epidemiology level, which is conducive to developing deep insights into the genetic diversity and pathogenic characteristics of BPVs in dairy cows.

Background: Bovine papillomatosis is a type of proliferative tumor disease of skin and mucosae caused by bovine papillomavirus (BPV). As a transboundary and emerging disease in cattle, it poses a potential threat to the dairy industry. Objectives: The aim of this study is to detect and clarify the genetic diversity of BPV circulating in dairy cows in Xinjiang, China. Methods: 122 papilloma skin lesions from 8 intensive dairy farms located in different regions of Xinjiang, China were detected by polymerase chain reaction. The genetic evolution relationships of various types of BPVs were analyzed by examining this phylogenetic tree. Results: Ten genotypes of BPV (BPV1, BPV2, BPV3, BPV6, BPV7, BPV8, BPV10, BPV11, BPV13, and BPV14) were detected and identified in dairy cows. These were the first reported detections of BPV13 and BPV14 in Xinjiang, Mixed infections were detected, and there were geographical differences in the distribution of the BPV genotypes. Notably, the BPV infection rate among young cattle (< 1-year-old) developed from the same supply of frozen sperm was higher than that of the other young cows naturally raised under the same environmental conditions. Conclusions Genotyping based on the L1 gene of BPV showed that BPVs circulating in Xinjiang China displayed substantial genetic diversity. This study provided valuable data at the molecular epidemiology level, which is conducive to developing deep insights into the genetic diversity and pathogenic characteristics of BPVs in dairy cows.

Cystic echinococcosis (CE) in sheep is a hazardous zoonotic parasitic disease that is caused by Echinococcus granulosus (Eg). At present, serological test is an important diagnostic method for Eg infection in domestic animals. Here, a fusion protein Eg mefAg-1 harboring 8 dominant B-cell epitopes of Eg such as antigen B, tetraspanin 1, tetraspanin 6, reticulon and Eg95 was produced in E. coli and evaluated for CE in sheep by indirect ELISA. Eg mefAg-1 showed in ELISA a high sensitivity (93.41%) and specificity (99.31%), with a coincidence rate of 97.02%. Overall, it is suggested that the Eg mefAg-1 could be a potential antigen candidate for CE serodiagnosis in sheep.
Animals, Domestic ; Echinococcosis ; Echinococcus granulosus ; Enzyme-Linked Immunosorbent Assay ; Epitopes, B-Lymphocyte ; Methods ; Parasitic Diseases ; Sensitivity and Specificity ; Serologic Tests ; Sheep

As an important zoonotic pathogen, Staphylococcus aureus has led to serious mastitis and endometritis in infected dairy cows. In this study, a total of 164 strains of S. aureus were isolated from dairy cows in Xinjiang Province, China, and subjected to assays to determine drug susceptibility and biofilm (BF) formation ability. Enterotoxin-related genes were detected, and the transcription levels of genes related to BF formation were determined by using reverse transcription-quantitative polymerase chain reaction. Moreover, the pathogenicity of isolates with different BF formation abilities was determined by measuring their hemolysis activity, half lethal dose (LD₅₀) and organ bacterial load. The results showed that 86.0% of S. aureus isolates could form BF. Among them, 42.1% of the strains had weak BF formation ability, and most strains with a strong BF formation ability were ica gene carriers. The S. aureus isolates displayed multidrug resistance and their drug resistance was positively correlated with their BF formation ability. Moreover, 96.3% of the S. aureus isolates carried enterotoxin genes. Among them, the detection rates of the novel enterotoxin genes were higher than those of conventional enterotoxin genes. Furthermore, isolates with a strong BF formation ability had higher LD50 but lower hemolysis ability and organ bacterial load than those of the isolates with weak or no BF ability. However, isolates without BF ability produced more severe pathological changes than those of isolates with strong BF formation ability. These findings suggest that higher BF ability and presence of novel enterotoxin genes are important characteristics of S. aureus isolates from dairy cows in Xinjiang Province, China, and such isolates may pose potential threats to food safety.
Bacterial Load ; Biofilms ; China ; Drug Resistance ; Drug Resistance, Microbial ; Drug Resistance, Multiple ; Endometritis ; Enterotoxins ; Female ; Food Safety ; Hemolysis ; Lethal Dose 50 ; Mastitis ; Polymerase Chain Reaction ; Staphylococcus aureus ; Staphylococcus ; Virulence

Objective To investigate the effects of shRNA targeting a disintegrin and metalloproteinases 17(ADAM17)on the proliferation of human breast cancer MCF-7 cells in hypoxia environment.Methods The four specific ADAM17-shRNA se-quences aiming at ADAM17 were designed,transfected into MCF-7 cells by electroporation,and cultured in hypoxia environment. The experiment was divided into the control group (blank phosphate buffer solution,PBS),nonsense sequence group (transfected with ADAM17-shNC)and shRNA transfection group (transfected with ADAM17-shRNA,the highest silencing efficiency of shR-NA was selected for following experiments).Real-time PCR was used to detect the expression of ADAM17 mRNA.The prolifera-tion ability and cell cycle change of MCF-7 cells were detected by iCELLigence and flow cytometry (FCM),respectively.Results Compared with control group and nonsense sequence group,the four ADAM17-shRNA transfection groups all had the silence effect on ADAM17 gene expression (P <0.05 ),the difference was statistically significant(P <0.05 ),particularly shRNA1219 had the highest inhibitory rate (F =5.11,P <0.01 ).The cellular proliferation ability and cell growth speed in the shRNA transfection group were significantly decreased compared with the control group and nonsense sequence group (P <0.05).Most cells of shRNA transfection group remained in the G0/G1 phase (73.35 ± 2.45 ),which in the control group and nonsense sequence group was (62.56±2.35)and (62.68 ±1.20)respectively,the difference was statistically significant(P <0.05).The cell cycle progression was significantly delayed.Conclusion ADAM17-shRNA inhibits the proliferation of MCF-7 cells under hypoxic environment.

We report here a human case of Taenia asiatica infection which was confirmed by genetic analyses in Dali, China. A patient was found to have symptoms of taeniasis with discharge of tapeworm proglottids. By sequencing of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene, we observed nucleotide sequence identity of 99% with T. asiatica and 96% with T. saginata. Using the cytochrome b (cytb) gene, 99% identity with T. asiatica and 96% identity with T. saginata were found. Our findings suggest that taeniasis of people in Dali, China may be mainly caused by T. asiatica.
Adult ; Animals ; China ; Cytochromes b/genetics ; Electron Transport Complex IV/genetics ; Humans ; Male ; Phylogeny ; Sequence Homology, Nucleic Acid ; Taenia/classification/genetics/isolation & purification/*physiology ; Taeniasis/*parasitology

The tapeworm Taenia solium is an important human zoonotic parasite that causes great economic loss and also endangers public health. At present, an effective vaccine that will prevent infection and chemotherapy without any side effect remains to be developed. In this study, codon usage patterns in the T. solium genome were examined through 8,484 protein-coding genes. Neutrality analysis showed that T. solium had a narrow GC distribution, and a significant correlation was observed between GC12 and GC3. Examination of an NC (ENC vs GC3s)-plot showed a few genes on or close to the expected curve, but the majority of points with low-ENC (the effective number of codons) values were detected below the expected curve, suggesting that mutational bias plays a major role in shaping codon usage. The Parity Rule 2 plot (PR2) analysis showed that GC and AT were not used proportionally. We also identified 26 optimal codons in the T. solium genome, all of which ended with either a G or C residue. These optimal codons in the T. solium genome are likely consistent with tRNAs that are highly expressed in the cell, suggesting that mutational and translational selection forces are probably driving factors of codon usage bias in the T. solium genome.
Animals ; Base Sequence ; Codon/*genetics ; Evolution, Molecular ; *Genome, Helminth ; Helminth Proteins/*genetics ; Molecular Sequence Data ; Taenia solium/*genetics

Wnt proteins are a family of secreted glycoproteins that are evolutionarily conserved and considered to be involved in extensive developmental processes in metazoan organisms. The characterization of wnt genes may improve understanding the parasite's development. In the present study, a wnt4 gene encoding 491amino acids was amplified from cDNA of metacestodes of Taenia solium using reverse transcription PCR (RT-PCR). Bioinformatics tools were used for sequence analysis. The conserved domain of the wnt gene family was predicted. The expression profile of Wnt4 was investigated using real-time PCR. Wnt4 expression was found to be dramatically increased in scolex evaginated cysticerci when compared to invaginated cysticerci. In situ hybridization showed that wnt4 gene was distributed in the posterior end of the worm along the primary body axis in evaginated cysticerci. These findings indicated that wnt4 may take part in the process of cysticerci evagination and play a role in scolex/bladder development of cysticerci of T. solium.
Animals ; Base Sequence ; Cysticercosis/pathology ; Cysticercus/enzymology/*genetics ; DNA, Helminth/*genetics ; Gene Expression Regulation ; Humans ; In Situ Hybridization ; Real-Time Polymerase Chain Reaction ; Sequence Analysis, DNA ; Sus scrofa ; Swine ; Swine Diseases ; Taenia solium/embryology/enzymology/*genetics ; Wnt4 Protein/*genetics