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In the process of mining, there are rocks affected by cyclic disturbances, which have significant effects on the mechanical properties of rocks. To understand the loading rate effect of rocks under different cyclic loading and unloading methods,this paper carries out constant lower Unit cyclic loading and unloading, variable lower Unit cyclic loading and unloading tests on sillimanite specimens with different loading rates, comparatively analyzes the deformation characteristics, the energy evolution law and the destructive characteristics of the specimens under the two cyclic loading and unloading methods with different loading rates. The test results show that the peak strength and residual deformation of the specimen have different acceleration rate effects, but the peak strength is improved compared with the conventional uniaxial compression test; WITH the increase of the loading rate, the input energy, elastic energy and dissipation energy of the specimen in all stages show an increasing trend, but with some differences in the form of manifestation; the destruction of the specimen and IS morphology show the acceleration rate effect, and the degree of destruction is intensified with the increase of the loading rate. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of IL-21 in osteoclastogenesis of RAW264. 7 cells and its possible mechanism. Methods 1) RAW264.7 cells were treated with different concentrations of IL-21 (0, 1, 10, 20, and 40 ng/ml). After 5 days, TRAP staining was performed. The calcitonin receptor ( CTR ) expression was detected using Western blot and immunocytochemistry. The mRNA levels of CTR and Cathepsin-K were examined using real-time PCR. 2) Before adding IL-21 into the culture, various signaling pathway inhibitors ( AG490, LY294002 and PD98059) were incubated with RAW264. 7 for 30 min. Osteoclast formation was determined after 5 days culture. Phosphorylation of signaling proteins was determined using Western blot under the stimulation of IL-21. Results 1) Without the presence of RANKL, TRAP positive cells increased with the increase of IL-21 concentration. The strongest effect was at the 20 ng/ml concentration, and the effect decreased at the 40 ng/ml concentration. IL-21 promoted mRNA expression of CTR and Cathepsin-K. Western blot and immunocytochemistry showed that the expression of CTR in IL-21 group increased compared to that in control group. 2) The PI3K-AKT pathway inhibitor LY294002 significantly suppressed IL-21-induced osteoclastogenesis in RAW264. 7 cells. P-AKT expression increased after 5-15 min stimulation of IL-21. Conclusion IL-21 can induce osteoclastogenesis of RAW264.7 cells independent of RANKL via PI3K-AKT pathway. [ABSTRACT FROM AUTHOR]

The volatile oil from loquat seed was extracted by means of steam distillation and its chemical components were analyzed by GC-MS and its antioxidant activities in vitro were evaluated by total reducing power, and scavenging capacity against ABTS •, sodium nitrite. The results showed that twenty compounds, which occupied 89. 69% of total constituents, were identified and the major components were benzaldehyde and benzoic acid. The antioxidant activities of 25% volatile oil from loquat seed were better than that of the positive control in a concentration-dependent fashion. Therefore, the volatile oil from loquat seed possessed excellent antioxidant activities. [ABSTRACT FROM AUTHOR]

The current status of the application of data mining in Chinese medicine (TCM) safety research are analyzed in this paper, and the future development trend are discussed, which include: to establish ADR (adverse drug reaction) signal detection and automatic warning system based on traditional Chinese medicine (TCM) adverse reaction database, to explore the characteristics and influencing factors of TCM safety problems, to devise appropriate new algorithm, and to develop TCM adverse reaction literature mining.

Objective: Ayu (Plecoglossus altivelis) vibriosis threatens ayu aquaculture seriously caused by mass mortality due to severe infections. We characterized the vibriosis pathogen of ayu in Ninghai country., Methods: A dominant strain was isolated and identified by a series of biochemical and physiological tests. The lethal dose 50% (LD50) was calculated by the modified Karber's method. PCR amplification and sequence analysis were used to further identify the pathogen., Results: LD50 of ayu-H080701 was 1.2 x 10(4) CFU to ayu. PCR amplification showed that the bacterial universal primers for 16S rRNA gene and the specific primers for the metalloprotease (MP) gene of Listonella anguillarum worked. 16S rRNA gene analysis showed that ayu-H080701 shared 99.4%-99.5% nucleotide identical to L. anguillarum isolates, while 94.3% and 91.9% nucleotide identical to L. pelagius and Photobacterium damselae respectively. Metalloprotease analysis showed that ayu- H080701 shared 97.6%-98.8% amino acid sequence identical to L. anguillarum isolates, while lower than 75.6 % to other bacteria. Phylogenetic analysis showed that ayu-H080701 grouped constantly with L. anguillarum isolates., Conclusion: The biochemical, physiological tests and sequence analysis all strongly supported the identification of the pathogen causing ayu vibriosis in Ninghai country, China, as an isolate of L. anguillarum.

Objective: To investigate the feasibility of the complex of the fibrin sealant (FS) and the bone marrow mesenchymal stem cells(MSCs) to create a new cartilage in the nude mice by the issue engineering technique., Methods: The MSCs were isolated from healthy humans and were expanded in vitro. And then the MSCs were induced by the defined medium containing the transforming growth factor beta1 (TGF-beta1), dexamethasone, and ascorbic acid. The biomechanical properties of the chondrocytes were investigated at 7 and 14 days. The MSCs induced for 7 days were collected and mixed with FS. Then, the FS-MSCs mixture was injected by a needle into the dorsum of the nude mice in the experimental group. In the two control groups, only FS or MSCs were injected respectively. The specimens were harvested at 6 and 12 weeks,and the ability of chondrogenesis in vivo was investigated by the gross observation, HE, Alcian Blue staining, and type II collagen immunohistochemistry., Results: The MSCs changed from a spindle-like fibroblastic appearance to a polygonal shape when transferred to the defined medium, and could be induced to express the chondrocyte matrix. After an injection of the mixture, the cartilage-like tissue mass was formed, and the specimens were harvested from the mass at 6 and 12 weeks in the experimental group. The tissue mass at 6 weeks was smaller and relatively firm in texture, which had a distinct lacuna structure. And glycosaminoglycan (GAG) and Type II Collagen expressions were detected. The tissue mass at 12 weeks was bigger, firmer and glosser with the mature chondrocytes lying in the lacuna structure. The positive Alcian blue and Collagen II immunohistochemistry stainings were stronger at 12 weeks than at 6 weeks. But there was no cartilage-like tissue mass formed in the two control groups., Conclusion: This study demonstrates that the fibrin sealant and the bone marrow mesenchymal stem cells can be successfully used in a constructing technique for the tissue engineered injectable cartilage.