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Toll-like receptors (TLRs) are innate pattern recognition receptors that play an important role in host resistance to pathogenic microbes. In this study, we cloned the coding region of the yak TLR family (1–10) genes and used bioinformatics to analyze gene characteristics. Real-time fluorescence quantitative polymerase chain reaction was used to detect TLR expression levels in different tissues. Yak TLR genes exhibited high homologies with other species. At the nucleotide level, yak shared more than 96 % homology with cattle and sheep and 75–87 % homology with human and mouse. At the amino acid level, yak shared 90–99 % homology with cattle and sheep and 64–86 % homology with human and mouse. Yak showed close evolutionary relationship with cattle and sheep, which formed a branch of mammals together with TLRs from human, horse, and mouse, among others, and formed a branch with a longer genetic distance with chicken. TLR1, 2, 6, and 10 and TLR7, 8, and 9 were clustered in 2 individual branches, respectively. Fluorescent quantitation results showed that TLRs were expressed in all yak tissues, but different members showed different expression patterns. TLR2, 4, and 6 showed the highest expression in the spleen, followed by ovary, small intestine, kidney, and liver. TLR1, 5, 7, 8, 9, and 10 were most highly expressed in the kidney and showed higher expression in the liver, kidney, spleen, and other tissues. Our results will be useful for studies on immune molecular mechanisms and disease resistance breeding of yak and other plateau animals.

To more efficiently identify the microbial community of the yak rumen, the standardization of DNA extraction is key to ensure fidelity while studying environmental microbial communities. In this study, we systematically compared the efficiency of several extraction methods based on DNA yield, purity, and 16S rDNA sequencing to determine the optimal DNA extraction methods whose DNA products reflect complete bacterial communities. The results indicate that method 6 (hexadecyltrimethylammomium bromide-lysozyme-physical lysis by bead beating) is recommended for the DNA isolation of the rumen microbial community due to its high yield, operational taxonomic unit, bacterial diversity, and excellent cell-breaking capability. The results also indicate that the bead-beating step is necessary to effectively break down the cell walls of all of the microbes, especially Gram-positive bacteria. Another aim of this study was to preliminarily analyze the bacterial community via 16S rDNA sequencing. The microbial community spanned approximately 21 phyla, 35 classes, 75 families, and 112 genera. A comparative analysis showed some variations in the microbial community between yaks and cattle that may be attributed to diet and environmental differences. Interestingly, numerous uncultured or unclassified bacteria were found in yak rumen, suggesting that further research is required to determine the specific functional and ecological roles of these bacteria in yak rumen. In summary, the investigation of the optimal DNA extraction methods and the preliminary evaluation of the bacterial community composition of yak rumen support further identification of the specificity of the rumen microbial community in yak and the discovery of distinct gene resources.

A real-time PCR for detection and quantification of M. ovipneumoniae was developed using 9 recently sequenced M. ovipneumoniae genomes and primers targeting a putative adhesin gene p113. The assay proved to be specific and sensitive (with a detection limit of 22 genomic DNA) and could quantify M. ovipneumoniae DNA over a wide linear range, from 2.2 × 10(2) to 2.2 × 10(7) genomes.

Psoriasis is a common chronic inflammatory skin disease and its underlying pathogenesis is still not fully understood. Therapeutic interventions are currently limited and restricted to the treatment of symptoms rather than targeting the mechanisms underlying the disease. Vascular remodeling is a hallmark of psoriasis; however, anti-vascular strategies to treat psoriasis have received little attention to date, particularly systemic treatment with a small molecule compound. The aim of this study was to investigate the anti-inflammatory effect of a newly identified vascular endothelial growth factor (VEGF) receptor 2 inhibitor, SKLB1002, and its possible mechanism of action in a transgenic mouse model of psoriasis. Fifteen 8-12-week‑old K14-VEGF transgenic mice received consecutive intraperitoneal (i.p.) injections of SKLB1002, vehicle or saline for 4 weeks. After 4 weeks of treatment, the disease symptoms were assessed and histological analyses were performed on ear sections by hematoxylin and eosin (HE) and immunohistochemistry staining. Systemic treatment with SKLB1002 reduced symptoms of ear inflammation in K14/VEGF transgenic mice, the pathological score was significantly decreased, and acanthosis, focal parakeratosis, hyperkeratosis and hemangiectasis were improved. Furthermore, systemic treatment with SKLB1002 significantly reduced vascular abnormalities, permeability and T-cell infiltration. These results demonstrated that targeted inhibition of VEGFR2 by a small molecule inhibitor is an effective method, which may be a new therapeutic option for psoriasis therapy.

We report here the complete genomic sequence of the giant panda rotavirus strain CH-1. This work is the first to document the complete genomic sequence (segments 1 to 11) of the CH-1 strain, which offers an effective platform for providing authentic research experiences to novice scientists.

Staphylococcus aureus produces a spectrum of enterotoxin that is recognized as the main reason for causing staphylococcal food poisoning. The aim of the current study was to investigate the phenotypic characteristics and enterotoxin genotypes of S. aureus isolated from food poisoning sufferers. On the basis of the amplification of 16S rRNA and nuc gene specific to S. aureus assay and the phenotype (hemolytic activity, thermal stable nuclease [Tnase] test, and biofilm formation), all isolates were identified as S. aureus. To genotypically characterize S. aureus isolates, genes encoding staphylococcal enterotoxin (sea, seb, sec, sed, see, seg, seh, sei, sej, sek, sem, sen, ser, and seu) were investigated by using polymerase chain reaction technique. The results showed that the eight isolates of S. aureus had different enterotoxin genotypic characteristics, which was the main cause of food poisoning. One isolate contained 10 enterotoxin genes, and the other 7 isolates carried 3 or more enterotoxin genes. The frequency of the newly identified enterotoxin genes (seg-seu) was higher than classical genes (sea-see). Overall, multi-gene detection rates were 75% (for sek, ser, and seu); 50% (for sea and sem); 37.5% (for sen, seg, and sei); and 12.5% (for seb, sec, sed, and sej), respectively. The see and seh gene were not detected in any isolates. The current study provided the exact distribution of enterotoxin genes in eight S. aureus strains from food poisoning sufferers, which indicated that the pathogenicity of the newly identified enterotoxin should be highlighted. The need for prevention of food poisoning occurrences caused by enterotoxin of S. aureus should be reinforced.

Background Canine distemper virus (CDV) infects a variety of carnivores, including wild and domestic Canidae. In this study, we sequenced and phylogenetic analyses of the hemagglutinin (H) genes from eight canine distemper virus (CDV) isolates obtained from seven raccoon dogs (Nyctereutes procyonoides) and a giant panda (Ailuropoda melanoleuca) in China. Results Phylogenetic analysis of the partial hemagglutinin gene sequences showed close clustering for geographic lineages, clearly distinct from vaccine strains and other wild-type foreign CDV strains, all the CDV strains were characterized as Asia-1 genotype and were highly similar to each other (91.5-99.8% nt and 94.4-99.8% aa). The giant panda and raccoon dogs all were 549Y on the HA protein in this study, irrespective of the host species. Conclusions These findings enhance our knowledge of the genetic characteristics of Chinese CDV isolates, and may facilitate the development of effective strategies for monitoring and controlling CDV for wild canids and non-cainds in China.