First report and genetic diversity of porcine bufavirus in China.

BACKGROUND: Bufavirus is a newly discovered zoonotic virus reported in numerous mammals and humans. However, the epidemiological and genetic characteristics of porcine bufaviruses (PBuVs) in China remain unclear. METHODS: To detect PBuVs in China, 384 samples (92 fecal and 292 serum specimens) were collected from 2017 to 2018, covering six provinces in China, and were evaluated by nested PCR. Further, the positive samples from different provinces were selected to obtain the complete genome of Chinese PBuVs. RESULTS: The prevalence rate of PBuV was 16.7% in Chinese domestic pigs in the Guangdong, Guangxi, Fujian, Jiangxi, Anhui, and Henan provinces. Additionally, the positive rate of fecal specimens was higher than that of the serum samples. Next, we sequenced nine near-complete genomes of Chinese field PBuV strains from different provinces. Homology and phylogenetic analyses indicated that Chinese PBuVs have high genetic variation (93.3-99.2%), showed higher nucleotide identity with an Austrian PBuV strain (KU867071.1), and developed into different branches within the same cluster. CONCLUSION: To our knowledge, this is the first report on PBuV in China, expanding the geographic boundaries of PBuV circulation. Our data demonstrate that PBuVs are widely distributed in the six Chinese provinces. Moreover, these Chinese PBuVs exhibit genetic variation and continuous evolution characteristics. Taken together, our findings provide a foundation for future studies on bufaviruses.

Effects of microRNA-206 and its target gene IGF-1 on sevoflurane-induced activation of hippocampal astrocytes in aged rats through the PI3K/AKT/CREB signaling pathway.

The study aims to explore the effects of microRNA-206 (miR-206) targeting IGF-1 on the activation of hippocampal astrocytes in aged rats induced by sevoflurane through the PI3K/AKT/CREB signaling pathway. Wistar rats and astrocytes were divided into the normal/blank, sham/negative control (NC), sevoflurane (sevo), miR-206 mimics+sevo, miR-206 inhibitors+sevo, miR-206 NC+sevo, IGF-1 shRNA+sevo, and miR-206 inhibitors+IGF-1 shRNA+sevo groups. The Morris water maze test was exhibited to assess the cognitive functions. Glial fibrillary acidic protein (GFAP) expression was detected by immunofluorescence assay. Western blotting and RT-qPCR were used to detect the expression of miR-206, IGF-1, PI3K, AKT, CREB, pPI3K, pAKT, pCREB, cytochrome-c (Cyt-c), and caspase-3. Cell viability and apoptosis were detected by MTT assay and annexin V/PI double staining respectively. Mitochondrial transmembrane potential (MTP) were determined by flow cytometry. The IGF-1 shRNA+sevo group showed reduced miR-206 expression. Compared with the normal/blank group, the sevo, and miR-206 NC+sevo groups showed decreased miR-206 and GFAP expressions, cell viability and MTP but increased expressions of IGF-1, PI3K, AKT, CREB, pPI3K, pAKT, pCREB, Cyt-c and caspase-3, as well as cell apoptosis. Similar trends were observed in the miR-206 inhibitors+sevo group when compared with the sevo group. The study provides evidence that miR-206 alleviates the inhibition of activation of hippocampal astrocytes in aged rats induced by sevoflurane by targeting IGT-1 through suppressing the PI3K/AKT/CREB signaling pathway.

Suppression of Long Non-Coding RNA LINC00652 Restores Sevoflurane-Induced Cardioprotection Against Myocardial Ischemia-Reperfusion Injury by Targeting GLP-1R Through the cAMP/PKA Pathway in Mice.

BACKGROUND/AIMS: Long non-coding RNA (lncRNA) and glucagon-like peptide 1 receptor (GLP-1R) are crucial for heart development and for adult heart structural maintenance and function. Herein, we performed a study to explore the effect of lncRNA LINC00652 (LINC00652) on myocardial ischemia-reperfusion (I/R) injury by targeting GLP-1R through the cyclic adenosine monophosphate-protein kinase A (cAMP/PKA) pathway. METHODS: Bioinformatics software was used to screen the long-chain non-coding RNAs associated with myocardial ischemia-reperfusion and to predict target genes. The mRNA and protein levels of LINC00652, GLP-1R and CREB were detected by RT-qPCR and western blotting. In order to identify the interaction between LINC00652 and myocardial I/R injury, the cardiac function, the hemodynamic changes, the pathological changes of the myocardial tissues, the myocardial infarct size, and the apoptosis of myocardial cells of mice were measured. Meanwhile, the levels of serum IL-1ß and TNF-α were detected. RESULTS: LINC00652 was overexpressed in the myocardial cells of mice with myocardial I/R injury. GLP-1R is the target gene of LINC00652. We also determined higher levels of LINC00652 and GLP-1R in the I/R modeled mice. Additionally, si-LINC00652 decreased cardiac pathology, infarct size, apoptosis rates of myocardial cells, and levels of IL-1ß and TNF-α, and increased GLP-1R expression cardiac function, normal hemodynamic index, and the expression and phosphorylation of GLP-1R and CREB proteins. CONCLUSION: Taken together, our key findings of the present highlight LINC00652 inhibits the activation of the cAMP/PKA pathway by targeting GLP-1R to reduce the protective effect of sevoflurane on myocardial I/R injury in mice.

MicroRNA-374 Exerts Protective Effects by Inhibiting SP1 Through Activating the PI3K/Akt Pathway in Rat Models of Myocardial Ischemia-Reperfusion After Sevoflurane Preconditioning.

BACKGROUND/AIMS: Ischemic heart disease is a leading cause of death in cardiovascular diseases, and microRNAs (miRs) have been reported to be potential therapeutic targets in heart disease. Herein, this study aims to investigate the effects of microRNA (miR)-374 on myocardial ischemia-reperfusion (I/R) injury in rat models pretreated with sevoflurane by targeting SP1 through the PI3K/Akt pathway. METHODS: SD rats were grouped into sham, I/R and sevoflurane + I/R (sevoflurane preconditioning and I/R) groups. The biochemical indicators, pathological changes, positive expression of SP1 protein, and apoptosis rates were measured using biochemical detection, Evans blue-TTC staining, immunohistochemistry and TUNEL staining. RT-qPCR and Western blotting were used to investigate the expression of miR-374 mRNA and the protein expression of SP1, PI3K, HO-1, p53, iNOS, c-fos, Akt/p-Akt, and GSK-3ß/p-GSK-3ß. Cardiomyocytes were treated with miR-374 mimics, miR-374 inhibitors, or siRNA-SP1. Cardiomyocyte proliferation and cycle distribution and apoptosis were studied by MTT and flow cytometry. RESULTS: Compared with the I/R group, in the sevoflurane + I/R group, serum SOD and IL-10 increased, while MDA, LDH, CK, TNF-α, IL-6 and IL-10 decreased, as did the percentage of infarct area, the positive rate of SP1 and the apoptosis index. The expression of SP1, p53, iNOS and c-fos decreased, and the miR-374 expression of PI3K, HO-1, Akt/p-Akt, GSK-3ß/p-GSK-3ß increased. With the upregulation of miR-374 and the downregulation of SP1, the expression of SP1, p53, iNOS and c-fos decreased, as did the proportion of cells in G1 phase and the apoptosis rate; the expression of PI3K, HO-1, Akt/p-Akt, GSK-3ß/p-GSK-3ß increased. The results in the miR-374 inhibitor group contrasted with the above results. CONCLUSION: The results indicated that miR-374 could alleviate myocardial I/R damage in rat models pretreated with sevoflurane by targeting SP1 by activating the PI3K/Akt pathway.

Chemical constituents from the fruits of Psoralea corylifolia and their protective effects on ionising radiation injury.

Two new flavonoids, corylifol F (1) and corylifol G (2), together with 19 known compounds, were isolated from the fruits of Psoralea corylifolia L.. The structures of these compounds were determined by interpretation of spectroscopic data and comparison with literature properties. The radioprotective effects of the isolated compounds against ionising radiation damage were also evaluated in vitro. The results showed that corylifol A exhibited radioprotective effects in both HBL-100 and MCF-7 cells, while psoralen, isopsoralen, corylifol C and bakuchiol showed obvious selective action to protect HBL-100 cells against damage caused by ionising radiation.

Emergence of novel recombination lineage 3 of porcine reproductive and respiratory syndrome viruses in Southern China.

Lineage 3 of porcine reproductive and respiratory syndrome viruses, which belong to North America type 2, has a long epidemic history in China. The novel lineage 3 viruses constantly emerging in recent years are characterized by a high detection rate and significant pathogenicity. In this study, we investigated the prevalence of lineage 3 in southern China and selected two isolated strains for genome and virulence analyses. A cross-sectional epidemiology investigation indicated that the prevalence of lineage 3 antigens was 35.68% (95% CI: 27.6-44.3%) among 227 samples collected from over 100 infected farms from January 2016 to July 2017 in southern China. Two novel isolates of lineage 3 were selected. After 20 passages, Marc-145 cells were not susceptible to those viruses. Full-length genome analysis indicated that the two strains share 95.2% homology with each other and 95.7%-96.2% with highly pathogenic porcine reproductive and respiratory syndrome viruses (HP-PRRSVs; JXA1-like strain, lineage 8.7). Phylogenetic and molecular evolutionary results showed that for the two isolates, HP-PRRSV provides most of the ORF1 gene. Animal experiment revealed discrepancies in virulence between the strains. Although challenge resulted in 100% morbidity, the isolate carrying most of the HP-PRRSV ORF1 caused severe clinical symptoms and 40% mortality, whereas the other isolate containing part of the ORF1 gene caused no mortality. Overall, these findings suggest that lineage 3 viruses might be commonly circulating in most of southern China. Frequent recombination events within HP-PRRSVs of this lineage with changing virulence could represent potential threats to the pig industry.

Phylogeography, phylodynamics and the recent outbreak of lineage 3 porcine reproductive and respiratory syndrome viruses in China.

Novel highly pathogenic porcine reproductive and respiratory syndrome viruses (PRRSVs) have attracted increasing attention owing to their continual high emergence and recent re-emergence. Recently, lineage 3 PRRSVs, belonging to the type 2 viruses, with novel characteristics and increased virulence have been continuously re-emerging in China, thereby posing a great threat to pig farming. However, available information about lineage 3 is limited. Here, we carried out molecular epidemiological investigations for PRRSV surveillance in most regions of China from 2007 to 2017. More than 3,000 samples were obtained, amounting to 73 sequences of lineage 3 viruses. The origin, demographic history and spread pattern of lineage 3 PRRSVs were investigated combining with the database globally. Phylogeography and phylodynamic analyses within a Bayesian statistical framework revealed that lineage 3 viruses originated in Taiwan. Followed by subsequent propagation to different areas and geography, it dichotomized into two endemic clusters. South China has become an epicentre for these viruses, which diffused into China's interiors in recent years. Furthermore, viral dispersal route analysis revealed the risk of viral diffusion. Overall, the origin, epidemic history and geographical evolution of lineage 3 PRRSVs were comprehensively analysed in this study. In particular, the epicentre of southern China and the diffusion routines of the viruses are highlighted in this study, and the possible continuous transmission of the novel lineages poses the biggest threat to pig farmers.

Ginsenoside Rg1 Suppresses Type 2 PRRSV Infection via NF-κB Signaling Pathway In Vitro, and Provides Partial Protection against HP-PRRSV in Piglet.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a huge threat to the modern pig industry, and current vaccine prevention strategies could not provide full protection against it. Therefore, exploring new anti-PRRSV strategies is urgently needed. Ginsenoside Rg1, derived from ginseng and notoginseng, is shown to exert anti-inflammatory, neuronal apoptosis-suppressing and anti-oxidant effects. Here we demonstrate Rg1-inhibited PRRSV infection both in Marc-145 cells and porcine alveolar macrophages (PAMs) in a dose-dependent manner. Rg1 treatment affected multiple steps of the PRRSV lifecycle, including virus attachment, replication and release at concentrations of 10 or 50 µM. Meanwhile, Rg1 exhibited broad inhibitory activities against Type 2 PRRSV, including highly pathogenic PRRSV (HP-PRRSV) XH-GD and JXA1, NADC-30-like strain HNLY and classical strain VR2332. Mechanistically, Rg1 reduced mRNA levels of the pro-inflammatory cytokines, including IL-1ß, IL-8, IL-6 and TNF-α, and decreased NF-κB signaling activation triggered by PRRSV infection. Furthermore, 4-week old piglets intramuscularly treated with Rg1 after being challenged with the HP-PRRSV JXA1 strain display moderate lung injury, decreased viral load in serum and tissues, and an improved survival rate. Collectively, our study provides research basis and supportive clinical data for using Ginsenoside Rg1 in PRRSV therapies in swine.

Local melting to design strong and plastically deformable bulk metallic glass composites.

Recently, CuZr-based bulk metallic glass (BMG) composites reinforced by the TRIP (transformation-induced plasticity) effect have been explored in attempt to accomplish an optimal of trade-off between strength and ductility. However, the design of such BMG composites with advanced mechanical properties still remains a big challenge for materials engineering. In this work, we proposed a technique of instantaneously and locally arc-melting BMG plate to artificially induce the precipitation of B2 crystals in the glassy matrix and then to tune mechanical properties. Through adjusting local melting process parameters (i.e. input powers, local melting positions, and distances between the electrode and amorphous plate), the size, volume fraction, and distribution of B2 crystals were well tailored and the corresponding formation mechanism was clearly clarified. The resultant BMG composites exhibit large compressive plasticity and high strength together with obvious work-hardening ability. This compelling approach could be of great significance for the steady development of metastable CuZr-based alloys with excellent mechanical properties.