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Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heavy ion beam（HIB）irradiation, with high mutagenesis rate, broad mutagenesis spectrum and stable mutant, has been widely used in the implementation of industrial microbial breeding. With the development of sequencing technology, a more comprehensive understanding of the biological information at multiple levels such as genome, transcriptome, proteome, and metabolome may be achieved via study on the mutagenesis effect of HIB. This paper summarizes the research progress of microbial breeding using HIB, combining highthroughput sequencing technology to explore the biological effects of heavy ion mutagenesis. On this basis, a new idea of using omics methods to study the mutagenesis effect of HIB was further discussed with aim to provide references and suggestions for the breeding technology. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: In recent years, using tissue engineering technology to repair intervertebral disc degeneration has become a research hotspot in the field of OBJECTIVE: To compare the effect of silk fibroin/nano hydroxyapatite composite material combined with icariin and silk fibroin/nano hydroxyapatite composite in the repair of intervertebral disc degeneration. METHODS: Silk fibroin/nano hydroxyapatite hydrogel was prepared by physical blending and porogen. The hydrogel was directly physically mixed with icariin to prepare a hydrogel containing icariin (10 mmol/L). Animal models of intervertebral disc degeneration in New Zealand white rabbits were established by nucleus pulposus aspiration method. Thirty-six rabbits were randomly divided into 3 groups, with 12 in each group. The model group was injected with PBS using microinjector into intervertebral disc. The control group was injected with silk fibroin/hydroxyapatite hydrogel and bone marrow mesenchymal stem cell suspension. The experimental group was injected with fibroin/hydroxyapatite hydrogel containing icariin and bone marrow mesenchymal stem cell suspension. The normal group (n=12) was not modeled and did not receive any treatment. X-ray and MRI examinations were performed 4, 8, and 12 weeks after surgery. Histology (hematoxylin-eosin staining and toluidine blue staining), RT-PCR detection (type Il collagen, proteoglycan, Sox9 mRNA), and western blot assay (type II collagen, proteoglycan, Sox9 protein expression) were performed 12 weeks after surgery. alter RESULTS AND CONCLUSION: (1) X-ray films showed that the height of the intervertebral disc in the model group gradually decreased at 4, 8, and 12 weeks after the operation, while the height of the intervertebral disc in the control group and the experimental group increased gradually. Among them, the rabbit disc height in the experimental group recovered better than the control group. (2) Mitl demonstrated that at 4, 8, and 12 weeks after surgery, the T2 weighted image signal value of the rabbit intervertebral disc in the model group gradually decreased, and gradually increased in the control group and the experimental group, of which the experimental group increased more significantly. (3) Hematoxylin-eosin staining showed that the nucleus pulposus tissue of the model group was obviously damaged, and the number of nucleus pulposus cells was remarkably reduced; the control group was less complete with a small amount of nucleus pulposus-like cell proliferation in the central nucleus pulposus. In the experimental group, nucleus pulposus tissue was intact, and a large number of nucleus pulposus-like cell proliferation could be seen in the central nucleus pulposus. (4) Toluidine blue staining showed that the nucleus pulposus of the mod model group was not stained, moderately stained in the control group, and deeply stained in the experimental group. (5) RT-PCR and western blot assay showed that the expression levels of type Il collagen, proteoglycan and Sox9 in the model group were lower than those in the normal group (P<0.05). The expression levels of type il collagen, proteoglycan and Sox9 in the control and experimental groups were higher than those of the model group (P<0.05). The expression levels of type il collagen, proteoglycan and Sox9 in the experimental group were higher than those in the control group (P<0.05). (6) The results have shown that the silk fibroin/hydroxyapatite hydrogel combined with icariin can promote the proliferation and differentiation of bone marrow mesenchymal stem cells into nucleus pulposus like cells, increase the synthesis of cell matrix and promote the repair of degenerative intervertebral disc. [ABSTRACT FROM AUTHOR]

BACKGROUND: Numerous studies have reported that transforming growth factor beta 3 combined with alginate and mesenchymal stem cells can repair cartilage defects in animal experiments. However, there is little research about the effect of transforming growth factor beta 3 and sodium alginate hydrogel combined with mesenchymal stem cells on repairing cartilage injury. OBJECTIVE: To compare effects of sodium alginate hydrogel and sodium alginate hydrogel loaded with transforming growth factor beta 3 on bone defect with bone marrow mesenchymal stem cells. METHODS: Rabbit bone marrow mesenchymal stem cells were isolated and cultured in vitro. A suitable amount of transforming growth factor beta 3 was added into sodium alginate solution. Before transplantation, bone marrow mesenchymal stem cell suspension was mixed with the hydrogel in equal volumes. Totally 48 New Zealand white rabbits were used to prepare unilateral articular cartilage defects and randomly divided into three groups. The injury group did not take any treatment; the control group was implanted with alginate hydrogel and bone marrow mesenchymal stem cell suspension; and the observation group was implanted with transforming growth factor beta 3-sodium alginate hydrogel complex and bone marrow mesenchymal stem cell suspension. At 12 weeks after operation, the samples were taken for gross and histological observation and type II collagen immunohistochemical staining and RT-PCR. RESULTS AND CONCLUSION: (1) General observation: At 12 weeks, the defect site of the injury group was filled with a large number of granulation tissue; the control group was filled with translucent cartilage like tissue; and the observation group was filled with new tissue. (2) Histological observation: At 12 weeks after operation, hematoxylin-eosin staining and safranin O staining showed that the defect site in the injury group was filled with more fibrous tissue, and there was a large gap in the central part. In the control group, there were more cartilage like tissue and fibroblast tissue; the surface was irregular; most of the material was degraded; and the material was surrounded by a large number of bone trabeculae. In the observation group, there was a large number of cartilage like tissue, with smooth surface and dense structure, similar to the surrounding normal cartilage tissue. (3) Immunohistochemical staining of type II collagen: only very weak positive staining was found in the injury group, while positive staining was found in the control group and the observation group, and the degree of positive staining in the observation group was significantly stronger than that in the control group. (4) RT-PCR detection: mRNA expression of type II collagen, Sox9 and glycosaminoglycan in the regenerated cartilage of the control group was lower than that of the observation group (P < 0.05). (5) The results suggest that transforming growth factor beta 3-sodium alginate hydrogel complex with bone marrow mesenchymal stem cells can promote the repair of articular cartilage defects and enhance the expression of articular cartilage genes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To solve the poor real-time performance of traditional pedestrian detection method, this paper proposed a new fast human detection method based on objectness detection. Firstly, this algorithm extracted binarized nonned gradients features from the training image sets . trained a cascade SVM classifier model fpr objectness estimation, and used this model to product some region of interest, which called candidate windows. Secondly, in order to further improve the quality of original candidate window's, it adjusted the sizes of these window's slightly and applied a rectangle cluster method to them. Finally, this algorithm extracted HOG features of these final candidate window's and employed a SVM classifier to check whether there wras a pedestrian. Experimental results demonstrate that the proposed algorithm outperforms the traditional detection models in detection speed while maintaining the comparable detection rate to the traditional detection method. [ABSTRACT FROM AUTHOR]