Expression profiles and characterization of microRNAs responding to chitin in Arthrobotrys oligospora.

Extracellular proteases, such as chitinases secreted by Arthrobotrys oligospora (A. oligospora), play a crucial role in the process of nematode infection. However, post-transcriptional regulation of gene expression involving microRNAs (miRNAs) in A. oligospora remains scarcely described. Hereto, transcriptome sequencing was carried out to analyze the expression profiles of chitin-responsive miRNAs in A. oligospora. Based on the RNA-seq data, the differential expression of miRNAs (DEmiRNAs) in response to chitin was screened, identified and characterized in A. oligospora. Meanwhile, the potential target genes were predicted by the online tools miRanda and Targetscan, respectively. Furthermore, the interaction of DEmiRNA with it's target gene was validated by a dual-luciferase reporter assay system. Among 85 novel miRNAs identified, 25 miRNAs displayed significant differences in expression in A. oligospora in response to chitin. Gene Ontology (GO) analysis showed that the potential genes targeted by DEmiRNAs were enriched in the biological processes such as bio-degradation, extracellular components and cell cycle. KEGG analysis revealed that the target genes were mainly involved in Hippo, carbon and riboflavin metabolic pathway. Outstandingly, chitinase AOL_s00004g379, which is involved in the hydrolysis metabolic pathway of chitin, was confirmed to be a target gene of differential miR_70. These findings suggest that chitin-responsive miRNAs are involved in the regulation of cell proliferation, predator hyphae growth and chitinase expression through the mechanisms of post-transcriptional regulation, which provides a new perspective to the molecular mechanisms underlying miRNAs-mediated control of gene expression in A. oligospora.

Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus in Xinjiang, China, from 2020 to 2022.

In recent years, the pig industry in Xinjiang, China, has been severely impacted by outbreaks of porcine epidemic diarrhea (PED), despite vaccination efforts. In this study, we investigated the genetic characteristics of currently prevalent porcine epidemic diarrhea virus (PEDV) strains in the region. We collected 548 samples from animals with suspected PED on large-scale pig farms in Xinjiang. Of these, 258 tested positive for PEDV by RT-PCR, yielding an overall positivity rate of 47.08%. S1 gene sequencing and phylogenetic analysis were conducted on 23 randomly selected RT-PCR-positive samples. Three endemic strains of PEDV (PEDV/CH/XU/2020, PEDV/CH/XK/2020, and PEDV/CH/XA/2020) were isolated, and their complete genome sequences were analyzed for evidence of genetic recombination. Sequence comparison of the S gene indicated significant variations in the S1 gene of the Xinjiang strains compared to the vaccine strains CV777, AJ1102, and LWL, with 90.2%-98.5% nucleotide sequence identity. Notably, both the N-terminal and C-terminal domains of the S protein showed significant variation. Genetic evolutionary analysis identified the GIIa subtype as the dominant genotype among the epidemic strains in Xinjiang. Recombination analysis revealed inter-subtype recombination events in the PEDV/CH/XK/2020 and XJ1904-34 strains. These findings highlight the extensive genetic variation in the predominant GIIa genotype of PEDV in Xinjiang, which does not match the genotype of the currently used vaccine strains. These data may guide further efforts toward the development of effective vaccines for the control of PED.

STM1863, a Member of the DUFs Protein Family, Is Involved in Environmental Adaptation, Biofilm Formation, and Virulence in Salmonella Typhimurium.

Salmonella Typhimurium (STM) is an important zoonotic Gram-negative pathogen that can cause infection in a variety of livestock and poultry. Meanwhile, as an important foodborne pathogen, the bacterium can survive in various stressful environments and transmits through the fecal-oral route, posing a serious threat to global food safety. To investigate the roles of STM1863, a member of the DUFs protein family, involved in STM environmental adaptation, biofilm formation, and virulence. We analyzed the molecular characteristics of the protein encoded by STM1863 gene and examined intra- and extracellular expression levels of STM1863 gene in mouse macrophages. Furthermore, we constructed STM1863 gene deletion and complementation strains and determined its environmental adaptation under stressful conditions such as acid, alkali, high salt, bile salt, and oxidation. And the capacity of biofilm formation and pathogenicity of those strains were analyzed and compared. In addition, the interaction between the promoter of STM1863 gene and RcsB protein was analyzed using DNA gel electrophoresis migration assay (electrophoretic mobility shift assay [EMSA]). The experiments revealed that acid adaptability and biofilm formation ability of STM1863 gene deletion strain were significantly weakened compared with the parental and complementary strains. Moreover, the adhesion and invasion ability of STM1863 deletion strain to mouse macrophages was significantly decreased, while the median lethal dose (LD50) increased by 2.148-fold compared with the parental strain. In addition, EMSA confirmed that RcsB protein could bind to the promoter sequence of STM1863 gene, suggesting that the expression of STM1863 gene might be modulated by RcsB. The present study demonstrated for the first time that STM1863, a member of the DUFs protein family, is involved in the modulation of environmental adaptation, biofilm formation, and virulence.

STnc1280, a trans-coding sRNA is involved in virulence modulation via targeting gldA mRNA in Salmonella Typhimurium.

Introduction. Salmonella Typhimurium (STM) is a food-borne Gram-negative bacterium, which can infect humans and a wide range of livestock and poultry, causing a variety of diseases such as septicaemia, enteritis and abortion.Hypothesis/Gap Statement. We will decipher the impacts of sRNA STnc1280 on STM virulence and provide a theoretical basis to reveal the regulatory role and molecular mechanism of STnc1280.Aim. The main objective of this study was to clarify whether sRNA STnc1280 exerts regulatory roles on STM pathogenicity.Methodology. The STnc1280 gene was amplified and its molecular characteristics were analysed in this study. Then, STnc1280 gene deletion strain (STM-ΔSTnc1280) and the complementary strain (ΔSTnc1280/STnc1280) were constructed by λ-Red homologous recombination method, respectively, to analyse of adhesion and invasive ability and pathogenicity of different strains. Subsequently, the potential target gene regulated by STnc1280 was predicted using target RNA2 software, followed by the verification of the interaction between STnc1280 and target mRNA using the dual plasmid reporter system (DPRS). Furthermore, the mRNA and protein level of target gene was determined using qRT-PCR and Western blot, respectively.Results. The results revealed that the cell adhesion and invasive ability and pathogenicity of STM-ΔSTnc1280 were significantly reduced compared to STM-SL1344 strain, indicating that the deficiency of STnc1280 gene significantly influenced STM pathogenicity. The DPRS results showed that STnc1280 can interact with the mRNA of target gene gldA, thus suppressing the expression of lacZ gene. Furthermore, the level of gldA mRNA was not influenced in STM-ΔSTnc1280, but the expression of GldA protein decreased significantly.Conclusion. Combining the bioinformatic analysis, these findings suggested that STnc1280 may bind to the SD sequence of gldA mRNA, hindering the binding of ribosomes to gldA mRNA, thereby inhibiting the expression of GldA protein to modulate the virulence of STM.

A Novel Spectrophotometric Method for Determination of Percarbonate by Using N, N-Diethyl-P-Phenylenediamine as an Indicator and Its Application in Activated Percarbonate Degradation of Ibuprofen.

Sodium percarbonate (SPC) concentration can be determined spectrophotometrically by using N, N-diethyl-p-phenylenediamine (DPD) as an indicator for the first time. The ultraviolet-visible spectrophotometry absorbance of DPD•+ measured at 551 nm was used to indicate SPC concentration. The method had good linearity (R2 = 0.9995) under the optimized experimental conditions (pH value = 3.50, DPD = 4 mM, Fe2+ = 0.5 mM, and t = 4 min) when the concentration of SPC was in the range of 0-50 µM. The blank spiked recovery of SPC was 95-105%. The detection limit and quantitative limit were 0.7-1.0 µM and 2.5-3.3 µM, respectively. The absorbance values of DPD•+ remained stable within 4-20 min. The method was tolerant to natural water matrix and low concentration of hydroxylamine (<0.8 mM). The reaction stoichiometric efficiency of SPC-based advanced oxidation processes in the degradation of ibuprofen was assessed by the utilization rate of SPC. The DPD and the wastewater from the reaction were non-toxic to Escherichia coli. Therefore, the novel Fe2+/SPC-DPD spectrophotometry proposed in this work can be used for accurate and safe measurement of SPC in water.

Transport and interaction of cadmium and active sludge extracellular polymeric substances in saturated sand influenced by ionic strength and composition.

Artificial groundwater recharge with reclaimed water (secondary effluent from wastewater treatment plants) has become an important approach to solving water scarcity worldwide. Microorganisms in activated sludge can secrete many extracellular polymeric substances (EPS). However, information on the impact of EPS on the movement of heavy metals in porous media and their environmental effects on underground networks is limited. To assess this risk, we extracted EPS from the aerobic section of a wastewater treatment plant using hot sodium hydroxide and conducted experiments using one-dimensional sand columns to investigate how ion composition and strength affect the movement and interaction of cadmium (Cd) and EPS in porous media. The results showed that EPS facilitated Cd migration in porous media. Sodium (Na) and calcium (Ca) ions promoted the migration of Cd in porous media and EPS-Cd complexation. The effect of Ca was more significant than that of Na. As the Na adsorption ratio increased, the migration ability of Cd in porous media and the complexation ability of EPS with Cd decreased. Therefore, when estimating the migration of EPS and Cd in subsurface environments, careful consideration should be given to prevent the risk of groundwater pollution.

The Small Non-coding RNA rli106 Contributes to the Environmental Adaptation and Pathogenicity of Listeria Monocytogenes.

Introduction: Listeria monocytogenes (LM) is an important food-borne pathogen, and the risk of its ingestion is a serious public health issue. The better its environmental adaptation mechanisms and pathogenicity are understood, the better the risk it poses can be countered. The regulatory role of the small non-coding RNA (sRNA) rli106 in the environmental adaptation and pathogenicity of LM is still unclear and this study investigated that role through its biological function. Material and Methods: An LM-Δrli106 gene deletion strain and an LM-Δrli106/rli106 gene complementation strain were constructed using the homologous recombination technique. Then, the adaptation of these strains to temperature, alkalinity, acidity, salinity, ethanol and oxidative stressors, their biofilm-forming ability and their pathogenicity in mice were investigated to show the regulatory roles of sRNA rli106 in LM. The target gene of rli106 was also predicted, and the interaction between it and rli106 was verified by a two-plasmid co-expressing system based on E.coli and Western blot analysis. Results: The adaptation of LM-Δrli106 to environmental stressors of pH 9, 5% NaCl and 8% NaCl, 3.8% ethanol and 5 mM H2O2 was significantly reduced when compared to the parental (LM EGD-e) and complementation strains. Also, the biofilm formation, cell adhesion, invasion, intracellular proliferation and pathogenicity of LM-Δrli106 in mice were significantly reduced. The results of two-plasmid co-expression and Western blot showed that rli106 can interact with the mRNA of the predicted DegU target gene. Conclusion: The sRNA rli106 may positively regulate the expression of the DegU gene in LM. This study sheds light on its regulatory roles in environmental adaptation and pathogenicity, providing new insights into the molecular mechanism of sRNA mediation in LM .

Polaronic defects in monolayer CeO2: Quantum confinement effect and strain engineering.

We uncover the structure, stability, and electronic properties of polaronic defects in monolayer (ML) CeO2 by means of first-principles calculations, with special attention paid to the quantum confinement effect induced by dimensionality reduction. Results show that the polaron can be more stabilized in ML CeO2 than in the bulk, while formation of oxygen vacancy (Vo2+) and polaron-vacancy complexes [(Vo2+-1polaron)1+, (Vo2+-2polaron)0] tends to be more difficult. The polaronic defect states sit deeper in energy within the bandgap of ML CeO2 compared to the bulk case. We further demonstrate that the epitaxial strain in ceria film, as normally exists when grown on metal substrate, plays a crucial role in regulating the defect energetics and electronic structures. In particular, the formation energies of polarons, Vo2+, (Vo2+-1polaron)1+, and (Vo2+-2polaron)0, generally decrease with tensile strain, leading to controllable defect concentration with strain and temperature. This study not only provides physical insights into the polaronic defects in ultrathin oxide films, but also sheds light on their potential technological applications in nanoelectronics, fuel cells, and catalysts.

The small RNA STnc1480 contributes to the regulation of biofilm formation and pathogenicity in Salmonella typhimurium.

Salmonella Typhimurium (STM) is one of the most important food-borne bacteria that seriously harms livestock and human beings, which is capable of regulating the expression of its own genes in a variety of ways to adapt to a wide variety of adverse environmental stresses. To understand the regulatory roles of sRNA STnc1480 on the capability of STM, the STnc1480 gene-deficient strain △STnc1480 and its complement strain △STnc1480/STnc1480 were generated, and the impacts of STnc1480 gene deficiency on the capability of responding to different environmental stresses, biofilm(BF)formation and pathogenicity were analyzed, respectively. Then the target genes that were regulated by STnc1480 were also analyzed and explored. Compared with parent and complement strains, the deficiency of the STnc1480 gene significantly reduced the BF formation. Moreover, the capacities of adhesion and invasiveness of the △STnc1480 strain to macrophages were also significantly reduced, while the LD50 in mice was significantly increased. The bacterial loads in liver and spleen were significantly reduced, and the pathological damage was alleviated. It was confirmed that the STnc1480 could be complementary to the 5'-UTR (-52 to -71 bases) region of lpfA mRNA. The bacterial dual-plasmid reporting system confirmed that STnc1480 was capable of interacting with the mRNA of the lpfA gene, suggesting that STnc1480 can regulate the 5'-UTR of the lpfA mRNA at post-transcription level to reduce the expression of the bacterial fimbria, thus reducing the BF formation and pathogenicity of STM.

Biological Characteristics of Recombinant Arthrobotrys oligospora Chitinase AO-801.

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/ß)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.

A Regulatory SRNA Rli43 Is Involved in the Modulation of Biofilm Formation and Virulence in Listeria monocytogenes.

Small RNAs (sRNAs) are a kind of regulatory molecule that can modulate gene expression at the post-transcriptional level, thereby involving alteration of the physiological characteristics of bacteria. However, the regulatory roles and mechanisms of most sRNAs remain unknown in Listeria monocytogenes(L. monocytogenes). To explore the regulatory roles of sRNA Rli43 in L. monocytogenes, the rli43 gene deletion strain LM-Δrli43 and complementation strain LM-Δrli43-rli43 were constructed to investigate the effects of Rli43 on responses to environmental stress, biofilm formation, and virulence, respectively. Additionally, Rli43-regulated target genes were identified using bioinformatic analysis tools and a bacterial dual plasmid reporter system based on E. coli. The results showed that the intracellular expression level of the rli43 gene was significantly upregulated compared with those under extracellular conditions. Compared with the parental and complementation strains, the environmental adaptation, motility, biofilm formation, adhesion, invasion, and intracellular survival of LM-Δrli43 were significantly reduced, respectively, whereas the LD50 of LM-Δrli43 was significantly elevated in BALB/c mice. Furthermore, the bacterial loads and pathological damages were alleviated, suggesting that sRNA Rli43 was involved in the modulation of the virulence of L. monocytogenes. It was confirmed that Rli43 may complementarily pair with the 5'-UTR (-47--55) of HtrA mRNA, thereby regulating the expression level of HtrA protein at the post-transcriptional level. These findings suggest that Rli43-mediated control was involved in the modulation of environmental adaptation, biofilm formation, and virulence in L. monocytogenes.

Intelligent Integration of Online Environmental Education Resources for English Language and Literature Majors Based on Collaborative Filtering Algorithm.

There are currently many different types and dispersed online educational resources, which inconvenience users and result in a low utilisation rate of resources. As a result, a new approach is required to realise the integration and recommendation of educational resources. This paper examines the intelligent integration and recommendation of online learning resources for English language and literature majors based on CF. The development of online English language and literature education resources is currently in the process of being discussed, and some flaws in the process are being examined in this paper. The creation and incorporation of a network education resource database are proposed as some strategies and recommendations. The information entropy method is employed to address the cold start problem brought on by the data sparseness of new users and new projects in CF. While this is happening, the recommendation process's similarity algorithm is being enhanced. This algorithm's decision support accuracy has been found to be 96.01% after extensive testing. Its accuracy is roughly 8% better than that of conventional CF, which has a precision of 8%. The results demonstrated a degree of accuracy in the improved algorithm.

Molecular Characteristics and Potent Immunomodulatory Activity of Fasciola hepatica Cystatin.

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-ß 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.

Topological band transition between hexagonal and triangular lattices with (px,py) orbitals.

By combining tight-binding modelling with density functional theory based first-principles calculations, we investigate the band evolution of two-dimensional (2D) hexagonal lattices with (px,py) orbitals, focusing on the electronic structures and topological phase transitions. The (px,py)-orbital hexagonal lattice model possesses two flat bands encompassing two linearly dispersive Dirac bands. Breaking the A/B sublattice symmetry could transform the model into two triangular lattices, each featuring a flat band and a dispersive band. Inclusion of the spin-orbit coupling and magnetization may give rise to quantum spin Hall and quantum anomalous Hall (QAH) states. As a proof of concept, we demonstrate that half-hydrogenated stanene is encoded by a triangular lattice with (px,py) orbitals, which exhibits ferromagnetism and QAH effect with a topological gap of ∼0.15 eV, feasible for experimental observation. These results provide insights into the structure-property relationships involving the orbital degree of freedom, which may shed light on future design and preparation of 2D topological materials for novel electronic/spintronic and quantum computing devices.

Molecular characterization of a novel GSTO2 of Fasciola hepatica and its roles in modulating murine macrophages.

Fascioliasis is an important zoonotic helminthic disease caused by Fasciola hepatica and poses a serious threat to global public health. To evade the immune response of its host (humans or animals), F. hepatica secretes various antioxidant enzymes such as glutathione transferase (GST) to facilitate its invasion, migration and parasitism in vivo. To investigate the biological functions of a novel omega-class GST (GSTO), the molecular features of GSTO2 of F. hepatica were analyzed by online software, and the biochemical properties in vitro of recombinant GSTO2 (rGSTO2) were dissected. Then, the regulatory roles of rGSTO2 protein in murine macrophages in vitro were further explored. The results revealed that the GSTO2 gene encodes 254 amino acids, which harbor the characteristic N-terminal domain (ßαßαßßα) and C-terminal domain (α-helical) of the cytoplasmic GST superfamily. GSTO2 was mainly expressed in F. hepatica vitelline follicles, intestinal tract, excretory pores and vitelline cells, with thioltransferase and dehydroascorbate reductase activities. Moreover, rGSTO2 protein could be taken up by murine macrophages and significantly inhibit the viability of macrophages. In addition, rGSTO2 protein could significantly promote apoptosis and modulate the expression of cytokines in macrophages. These findings suggested that F. hepatica GSTO2 plays an important role in modulating the physiological functions of macrophages, whereby this protein might be involved in immunomodulatory and anti-inflammatory roles during infection. This study provided new insights into the immune-evasion mechanism of F. hepatica and may contribute to the development of a potential anti-inflammatory agent.

Title: Caractérisation moléculaire d'une nouvelle GSTO2 de Fasciola hepatica et ses rôles dans la modulation des macrophages murins. Abstract: La fasciolase est une importante maladie helminthique zoonotique causée par Fasciola hepatica, qui constitue une menace sérieuse pour la santé publique mondiale. Pour échapper à la réponse immunitaire de son hôte (humain ou animal), F. hepatica sécrète diverses enzymes antioxydantes telles que la glutathion transférase (GST) pour faciliter son invasion, sa migration et son parasitisme in vivo. Pour étudier les fonctions biologiques d'une nouvelle GST de classe oméga (GSTO), les caractéristiques moléculaires de la GSTO2 de F. hepatica ont été analysées par un logiciel en ligne et les propriétés biochimiques in vitro de sa protéine recombinante (rGSTO2) ont été disséquées. Ensuite, les rôles régulateurs de la protéine rGSTO2 sur les macrophages murins in vitro ont été explorés plus avant. Les résultats ont révélé que le gène GSTO2 code pour 254 acides aminés, qui abritent le domaine N-terminal caractéristique (ßαßαßßα) et le domaine C-terminal (α-hélicoïdal) de la superfamille GST cytoplasmique. Chez F. hepatica, GSTO2 était principalement exprimée dans les follicules vitellins, le tractus intestinal, les pores excréteurs et les cellules vitellines, avec des activités de thioltransférase et de déhydroascorbate réductase. De plus, la protéine rGSTO2 a pu être absorbée par les macrophages murins et inhiber de manière significative la viabilité des macrophages. Enfin, la protéine rGSTO2 a pu favoriser de manière significative l'apoptose et moduler l'expression des cytokines dans les macrophages. Ces résultats suggèrent que la GSTO2 de F. hepatica joue un rôle important dans la modulation des fonctions physiologiques des macrophages, cette protéine pouvant être impliquée dans des rôles immunomodulateurs et anti-inflammatoires au cours de l'infection. Cette étude a fourni de nouvelles informations sur le mécanisme d'évasion immunitaire de F. hepatica et pourrait contribuer au développement d'un agent anti-inflammatoire potentiel.

Influence of coracoglenoid space on scapular neck fracture stability: biomechanical study.

BACKGROUND: The anatomical variation of the coracoglenoid space has the potential to influence the stability of scapular neck fractures. This paper aimed to investigate the mechanical mechanism underlying the influence of different coracoglenoid space types on scapular neck fractures by morphometric analysis and biomechanical experiments. METHODS: The morphology of 68 dried scapulae (left: 36; right: 32) was studied. Two variables, the length of the coracoglenoid distance (CGD) and the coracoglenoid notch (CGN), were measured. The distribution of CGN/CGD × 100% was used to identify the morphology of the coracoglenoid space. Each specimen was tested for failure under static axial compression loading. The average failure load, stiffness, and energy were calculated. RESULTS: Two coracoglenoid space types were identified. The incidence of Type I (''hook'' shape) was 53%, and that of Type II (''square bracket'' shape) was 47%. The CGD and CGN were significantly higher for type I than type II (13.81 ± 0.74 mm vs. 11.50 ± 1.03 mm, P < 0.05; 4.74 ± 0.45 mm vs. 2.61 ± 0.45 mm, P < 0.05). The average maximum failure load of the two types was 1270.82 ± 318.85 N and 1529.18 ± 467.29 N, respectively (P = 0.011). The stiffness and energy were significantly higher for type II than type I (896.75 ± 281.14 N/mm vs. 692.91 ± 217.95 N/mm, P = 0.001; 2100.38 ± 649.54 N × mm vs. 1712.71 ± 626.02 N × mm, P = 0.015). CONCLUSIONS: There was great interindividual variation in the anatomical morphology of the coracoglenoid space. Type I (hook-like) spaces bore lower forces, were less stiff, and bore less energy, which may constitute an anatomical predisposition to scapular neck fractures.

Prevalences and Characteristics of Trichuris Spp. Infection in Sheep in Pastoral Areas of the Tianshan, Xinjiang, China.

Introduction: Nematodes of the Trichuris genus are commonly reported parasites that can cause trichuriasis in many animals, which leads to inflammation, intestinal bleeding and reductions of productivity in livestock. Knowledge of the prevalence of Trichuris infestation in the Tianshan ovine population and of the nematode species parasitising the population is not exhaustive, and this study aimed to expand the knowledge. Material and Methods: A total of 1,216 sheep slaughtered in five pasture areas in the Tianshan Mountains of Xinjiang were investigated and a phylogenetic analysis based on the mitochondrial cox1 gene was performed to clarify the genetic relationships of the various Trichuris species. Results: Sheep totalling 1,047 were infected with Trichuris spp. establishing the rate at 86.1%. Using a morphological protocol, six documented and one undefined species were identified, namely T. gazellae, T. lani, T. ovina, T. longispiculus, T. concolor, T. discolor and Trichuris sp. Among them, T. gazellae and T. lani were the dominant species, accounting for 34.5% and 31.0% of Trichuris spp., respectively. Phylogenetic analysis divided the detected species of Trichuris spp. into two genetic clades (clade I and clade II). The six documented species that can infect sheep and the undefined species were clustered into clade I, with inter- and intra-species genetic diversity apparent. Conclusion: This survey described in detail the morphological characteristics of six known and one undefined species of Trichuris, which not only enriched the taxonomic information on record regarding Trichuris spp., but also provided valuable epidemiological data for the prevention and control of trichuriasis in sheep.

Development and evaluation of multi-epitope protein p72 (MeP72) for the serodiagnosis of African swine fever.

African swine fever (ASF) is an acute and severe infectious disease that seriously endangers the global porcine industry. In order to develop ASF serodiagnostic reagents with high specificity and sensitivity, in the present study, the antigenic epitopes of P72 protein of African swine fever virus (ASFV) were analyzed, and the ASFV multi-epitope fusion gene MeP72 in tandem with the dominant linear epitopes was constructed. The recombinant multi-epitope fusion MeP72 (reMeP72) was prepared in Escherichia coli. A colloidal gold-based immunochromatographic assay (CGIA) based on reMeP72 was developed for the detection of antibodies against ASFV. A total of 139 pig clinical serum samples were used for assessment of the potential diagnostic value of reMeP72. The results showed that CGIA did not cross-react with positive sera of viruses, such as classical swine fever virus (CSFV), porcine circovirus type 2 (PCV2), pseudorabies virus (PRV), porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza virus (SIV), showing high specificity. Sensitivity analysis showed that CGIA could detect ASFV-positive serum at a dilution of 1:64. Compared with commercial ASFV kits, the sensitivity and specificity of ASFV CGIA based on reMeP72 protein were 85.7% and 97.6%, respectively. The agreement rate of the two methods was 96.4%, showing a good detection performance. The results indicated that the reMeP72 was of potential value for the serodiagnosis of ASF. Keywords: African swine fever virus; P72 gene; antigenic protein; colloidal gold-based immunochromatographic assay.

sRNA STnc150 is involved in virulence regulation of Salmonella Typhimurium by targeting fimA mRNA.

Small RNAs (sRNAs) are essential virulent regulators in Salmonella typhimurium (STM). To explore the role of sRNA STnc150 in regulating STM virulence, we constructed a STnc150 deletion strain (ΔSTnc150) and its complementary strain (ΔSTnc150/C). Then, we compared their characteristics to their original parent strain experimentally, identified the target genes of STnc150 and determined the expression levels of target genes. The results showed that the ΔSTnc150 strain exhibited delayed biofilm formation, enhanced adhesion to macrophages, significantly reduced LD50, increased liver and spleen viral loads and more vital pathological damaging ability than its parent and complementary strains. Further, bioinformatics combined with the bacterial dual plasmid reporter system confirmed that the bases 72-88 of STnc150 locating at the secondary stem-loop structure of the STnc150 are complementary with the bases 1-19 in the 5'-terminal of fimA mRNA of the type 1 fimbriae subunit. Western blot analysis showed that fimA protein level was increased in STnc150 strain compared with its parent and complementary strains. Together, this study suggested that STnc150 can down-regulate STM fimA expression at the translation level, which provided insights into the regulatory mechanisms of sRNAs in virulence of STM.

Molecular detection and genetic diversity of bovine papillomavirus in dairy cows in Xinjiang, China.

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.