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The objective of this study is to review different methods to screen for the optimal model for preventing and treating chicken glandular and muscular gastritis syndrome. Twenty-four 40-day-old specific pathogen-free (SPF) chickens were randomly allocated into four groups (N = 6): polyethylene glycol + ammonium chloride group (M1 group), acetic acid + rhubarb group (M2 group), polyethylene glycol + rhubarb group (M3 group), and control group. The control group had free access to water, while the remaining groups received different doses of molding reagents added to their drinking water. The animal models were assessed based on clinical manifestations, histopathology findings, serological analysis, and composition of intestinal microbiota to establish an optimal approach for constructing an avian model of glandular and muscular gastritis. The SPF chickens in each model group exhibited typical symptoms of glandular and muscular gastritis, poor spirit, yellow loose stools with undigested feed, and enlargement and ulceration of the glandular and muscular stomach. Among these groups, the M3 group had the highest incidence rate of 100%. Compared to the control group, the body weight and body temperature of the chicken in the three model groups were reduced, and the glandular and muscular stomachs and duodenum showed different degrees of bleeding, mucosal abscission, and other pathological injuries. Additionally, the levels of serum IL-2 and α-amylase activity decreased while the content of IL-4 increased. After conducting 16s rDNA sequencing, it was observed that the abundance of Bacteroides, Faecalibacterium, and Ruminococcaceae UCG-014 was significantly increased in the model group compared to the control group. Conversely, there was a notable decrease in the levels of Megamonas and Lactobacillus, which are speculated to be associated with arachidonic acid metabolism, the NF-κB signaling pathway, and TNF signaling pathways. The combination of polyethylene glycol and rhubarb emerged as the most effective method for establishing the glandular and muscular gastritis model in SPF chickens. This constructed chicken model displayed distinct signs of damage to the glandular and muscular stomach, inflammatory response, and disturbance in the intestinal flora, thereby providing a foundation for future research on the prevention and treatment of this syndrome.

Klebsiella pneumoniae (K. pneumonia, KpI) is a predominate inducement of bovine mastitis, which is associated with high mortality and milk yield reduction. However, data is lacking on the molecular characteristics of bovine K. pneumoniae, limiting the risk assessment of its transmission through the food chain. Herein, we investigated the prevalence of K. pneumoniae in 6301 clinical mastitis (CM) milk samples from dairy cattle in northern area of China. In total, 183 K. pneumoniae isolates were recovered, with detection rates of 3.0% and 2.8% in 2018 and 2019, respectively. Like human clinical K. pneumoniae, all CM K. pneumoniae isolates belonged to one of three phylogroups: KpI (n = 143), Klebsiella. quasipneumoniae subsp. similipneumoniae (KpII-B) (n = 37), and Klebsiella variicola (KpIII) (n = 3). We detected the extended-spectrum β-lactamase-encoding genes blaSHV-2a, blaCTX-M-14, and blaCTX-M-15, as well as clpC, lpfA, lacI, lacZ, lacY, and the fecABDEIR operon in the KpI isolates, which may contribute to their pathogenicity and host adaptability in cows. The high prevalence of KpI in dairy farms may be problematic, as it showed relatively higher rates of antibiotic resistance and virulence gene carriage than the KpII-B and KpIII isolates. Furthermore, we observed distinct differences in population structure between CM- and human infection-associated KpI isolates, with the genes associated with invasive infection in humans rarely being observed in bovine isolates, indicating that few CM-associated K. pneumoniae isolates pose a threat to human health. Nevertheless, bovine KpII-B isolates shared a high level of nucleotide sequence identity with isolates from human infections and frequently carried the nitrogen-fixation gene nif, suggesting an association between KpII-B isolates from cattle and humans, and plant-derived bacteria.

Homologous recombination (HR) is an error-free DNA double-strand break (DSB) repair pathway, which safeguards genome integrity and cell viability. Human C-terminal binding protein (CtBP)—interacting protein (CtIP) is a central regulator of the pathway which initiates the DNA end resection in HR. Ubiquitination modification of CtIP is known in some cases to control DNA resection and promote HR. However, it remains unclear how cells restrain CtIP activity in unstressed cells. We show that the ubiquitin E3 ligase PPIL2 is recruited to DNA damage sites through interactions with an HR-related protein ZNF830, implying PPIL2’s involvement in DNA repair. We found that PPIL2 interacts with and ubiquitinates CtIP at the K426 site, representing a hereunto unknown ubiquitination site. Ubiquitination of CtIP by PPIL2 suppresses HR and DNA resection. This inhibition of PPIL2 is also modulated by phosphorylation at multiple sites by PLK1, which reduces PPIL2 ubiquitination of CtIP. Our findings reveal new regulatory complexity in CtIP ubiquitination in DSB repair. We propose that the PPIL2-dependent CtIP ubiquitination prevents CtIP from interacting with DNA, thereby inhibiting HR.

Abstract Background In May 2017, 17 dogs in a German Shepherd breeding kennel in northern China developed respiratory clinical signs. The owner treated the dogs with an intravenous injection of Shuang-Huang-lian, a traditional Chinese medicine, and azithromycin. The respiratory signs improved 3 days post-treatment, however, cysts were observed in the necks of eight dogs, and three of them died in the following 2 days. Case presentation Quantitative real-time PCR was used to detect canine influenza virus (CIV). All of the dogs in this kennel were positive and the remaining 14 dogs had seroconverted. Two of the dogs were taken to the China Agricultural University Veterinary Teaching Hospital for further examination. Two strains of influenza virus (A/canine/Beijing/0512–133/2017 and A/canine/Beijing/0512–137/2017) isolated from the nasal swabs of these dogs were sequenced and identified as avian-origin H3N2 CIV. For the two dogs admitted to the hospital, hematology showed mild inflammation and radiograph results indicated pneumonia. Cyst fluid was plated for bacterial culture and bacterial 16 s rRNA gene PCR was performed, followed by Sanger sequencing. The results indicated an Enterococcus faecalis infection. Antimicrobial susceptibility tests were performed and dogs were treated with enrofloxacin. All 14 remaining dogs recovered within 16 days. Conclusions Coinfection of H3N2 CIV and Enterococcus faecalis was detected in dogs, which has not been reported previously. Our results highlight that CIV infection might promote the secondary infection of opportunistic bacteria and cause more severe and complicated clinical outcomes.

During 2012–2017, we collected throat swabs from dogs in China to characterize canine influenza virus (CIV) A(H3N2) isolates. A new antigenically and genetically distinct CIV H3N2 clade possessing mutations associated with mammalian adaptation emerged in 2016 and replaced previously circulating strains. This clade probably poses a risk for zoonotic infection.

Since the first report of the plasmid-mediated, colistin-resistant gene, mcr-1, nine mcr genes and their subvariants have been identified. The spreading scope of mcr-1~10 varies greatly, suggesting that mcr-1~10 may have different evolutionary advantages. Depending on MCR family phylogeny, mcr-6 is highly similar to mcr-1 and -2, and mcr-7~10 are highly similar to mcr-3 and -4. We compared the expression effects of MCR-1~5 on bacteria of common physiological background. The MCR-1-expressing strain showed better growth than did MCR-2~5-expressing strains in the presence of colistin. LIVE/DEAD staining analysis revealed that MCR-3~5 expression exerted more severe fitness burdens on bacteria than did MCR-1 and -2. Bacteria expressing MCRs except MCR-2 showed enhanced virulence with increased epithelial penetration ability determined by trans-well model (p < 0.05). Enhanced virulence was also observed in the Galleria mellonella model, which may have resulted from bacterial membrane damage and different levels of lipopolysaccharide (LPS) release due to MCR expression. Collectively, MCR-1-expressing strain showed the best survival advantage of MCR-1~5-expressing strains, which may partly explain the worldwide distribution of mcr-1. Our results suggested that MCR expression may cause increased bacterial virulence, which is alarming, and further attention will be needed to focus on the control of infectious diseases caused by mcr-carrying pathogens.

In this work, we examined spatial and temporal trends for light rain days based on daily precipitation measurements, obtained from 1960 to 2014, from 590 meteorological stations in China. For the analyzed time interval, light rain days over eastern China were determined to decrease by 0.23 days·year−1. In western China, they increased by 0.3 days·year−1. To detect underlying causes for changes in light rain days, lower-tropospheric relative humidity was set as a proxy for light rain days. We then calculated the respective impacts of lower-tropospheric temperature and specific humidity on changes in light rain days. A comparison of the contributions of temperature and specific humidity resulted in the identification of the main cause of changes. Our results indicated that increases in lower-tropospheric temperatures reduced light rain days over the entire country, while variations in specific humidity dominated regional differences for light rain day trends.

In this work, rain totals from 1960–2014, obtained during the warm season (May to October) from 52 meteorological stations, over Xinjiang, China were classified as either light, moderate, or heavy rain in two sub-regions (northern and southern). Spatial and temporal trends for rain amounts and days for the three rain classes were determined. All light, moderate, and heavy rain amounts displayed increasing trends over the two sub-regions. Furthermore, heavy rain amounts contributed the most to changes in total rain amounts. Light rain days in northern Xinjiang significantly decreased, in contrast to increasing light rain days in southern Xinjiang and moderate and heavy rain days within two sub-regions. Results obtained from correlation and relative weights analyses implied that lower-tropospheric specific humidity was the main factor responsible for light rain day trends in Xinjiang. Increasing temperatures were not found to have a significant effect.

Precipitation has been considered to be a critical water source for both human livelihoods and ecosystems in Central Asia. Using observational data and gridded datasets, we studied the regional and seasonal differences of precipitation climate characteristics and variations in precipitation over Central Asia. Using observational data obtained from the China Meteorological Administration, Global Historical Climatology Network (V3.02), we divided Central Asia into four subregions (North, Center, Southwest, and Southeast) based on the differences in seasonal cycles of precipitation. ‘Single peaks’ were detected as types of seasonal cycles over the North and the Southeast, while ‘two peaks’ was the type that occurred in the Southwest. For the Center, the zone of transition between the North and the Southwest, each monthly precipitation value was higher than the Southwest’s and less than the North’s. GPCC (R2 of 0.89, RMSE of 64.5 mm/year) was proven to be the most suitable dataset of the four datasets (CRU, GPCC, MERRA, and TRMM) to describe precipitation in Central Asia, based on validation against observational data, and used to detect the spatial and temporal trend of precipitation in Central Asia and four subregions during 1960–2013. No significant trends were observed for annual precipitation in Central Asia, while precipitation in winter displayed a significant increase (0.11 mm/year). Additionally, significantly increasing trends (0.16, 0.27, 0.13, and 0.13 mm/year) were detected in spring, summer, autumn, and winter over the Southeast during 1960–2013.

Equine-origin H3N8 and avian-origin H3N2 canine influenza viruses (CIVs) prevalent in dogs are thought to pose a public health threat arising from intimate contact between dogs and humans. However, our understanding of CIV virulence is still limited. Influenza A virus PA-X is a fusion protein encoded in part by a +1 frameshifted open reading frame (X-ORF) in segment 3. The X-ORF can be translated in full-length (61 amino acids) or truncated (41 amino acids) form. Genetic analysis indicated that the X-ORFs of equine H3N8 and avian H3N2 influenza viruses encoded 61 amino acids but were truncated after introduction into dogs. To determine the effect of PA-X truncation on the biological characteristics of CIVs, we constructed four recombinant viruses on H3N8 and H3N2 CIV backgrounds bearing truncated or full-length PA-Xs. We observed that truncation of PA-X increased growth of both H3N8 and H3N2 CIVs in MDCK cells and suppressed expression from co-transfected plasmids in MDCK cells. Furthermore, truncation of PA-X enhanced viral pathogenicity in dogs as shown by aggravated clinical symptoms and histopathological changes, increased viral replication in the respiratory system, and prolonged virus shedding. Additionally, CIVs with truncated PA-Xs were transmitted more efficiently in dogs. Global gene expression profiling of the lungs of infected dogs revealed that differentially expressed genes were mainly associated with inflammatory responses, which might contribute to the pathogenicity of PA-X-truncated CIVs. Our findings revealed that truncation of PA-X might be important for the adaptation of influenza viruses to dogs. [ABSTRACT FROM AUTHOR]