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991.
Evaluating in vivo photochemical genotoxicity (photogenotoxicity) or photochemical carcinogenicity (photocarcinogenicity) in the skin that is actually exposed to light is important for estimating the risk of human exposure to chemicals under sunlight. With regard to the skin micronucleus test, Nishikawa et al. developed a reliable technique that is simple and in which the negative control has a stable background. In the present study, we applied 8-methoxypsoralen (8-MOP) and benzo[a]pyrene (B[a]P) to the backs of hairless mice and subjected the mice to irradiation by a sunlight simulator in order to investigate whether this test can detect photogenotoxicity of these chemicals. In the treatment with 8-MOP [0.00075% and 0.0015% (w/v)], a significant increase was observed in the frequency of micronucleated cells only under light irradiation using the sunlight simulator. At a high chemical dose, the frequency of micronucleated cells increased from 48h after the treatment, peaked at 96h, and then decreased at 168h. Furthermore, at 96h with the high dose under light irradiation, we frequently observed cells with nuclear buds. In the treatment with B[a]P [first experiment: 0.025% and 0.05% (w/v); second experiment: 0.005%, 0.01%, and 0.02% (w/v)], a significant increase was observed in the frequency of micronucleated cells at skin-irritating doses [0.01%, 0.02%, 0.025%, and 0.05% (w/v)] at 72 or 96h after the treatment only under light irradiation using the sunlight simulator. In conclusion, photogenotoxicity of 8-MOP and B[a]P was detected in the in vivo photochemical skin micronucleus study. 相似文献
992.
Tang Yanyan Qiu Xiaochen Hu Changli Li Jingjing Wu Lanrong Wang Weihua Li Xin Li Xiaoting Zhu Hong Sui Jiongming Wang Jingshan Qiao Lixian 《Molecular breeding : new strategies in plant improvement》2022,42(7):1-13
Molecular Breeding - Grain hardness (HI) is a key trait for wheat milling and end-use quality. Puroindoline genes (PINs) are the major genes responsible for grain hardness, but other QTLs... 相似文献
993.
Jinfeng Yang Zhaozhen Xu Manshu Sui Jihua Han Lijie Sun Xiuzhi Jia Haiyu Zhang Changsong Han Xiaoming Jin Fei Gao Yanhong Liu Yang Li Jianbin Cao Hong Ling Fengmin Zhang Huan Ren 《PloS one》2015,10(10)
ObjectiveTo characterize the significance of correlated autoantibodies in systemic lupus erythematosus (SLE) and its complication lupus nephritis (LN) in a large cohort of patients.MethodsClinical data were statistically analyzed in 1699 SLE patients with or without nephritis who were diagnosed and treated during 2002–2013 in the northeast region of China. Reactivity to a list of 16 autoantibodies was detected by the serum test Euroline ANA profile (IgG). Serum titers of the anti-nucleosome autoantibodies were measured by ELISA assays. Kidney biopsies were examined by pathologists. Immune complex deposition was identified by immunohistochemistry stain.ResultsSimultaneous positivity of anti-dsDNA, -nucleosome and -histone antibodies (3-pos) was prevalent in SLE patients with LN compared to Non-renal SLE patients (41% vs 11%, p< 0.001). Significant correlations were found between any two of the above three anti-nucleosome antibodies in LN patients. In comparison to non-3-pos cohorts, 3-pos patients with LN had significantly higher serum levels of the three antibodies and more active disease; was associated with type IV disease; suffered from more severe renal damages; received more intensive treatment and had worse disease outcome. The serum levels of these three autoantibodies in 3-pos LN patients were significantly decreased when they underwent clinical recovery.ConclusionsSimultaneous reactivity to anti-dsDNA, -nucleosome and -histone antibodies by Euroline ANA profile (IgG) may indicate severe nephropathy in patients with SLE. 相似文献
994.
995.
Shunyao Wu Fengjing Shao Jun Ji Rencheng Sun Rizhuang Dong Yuanke Zhou Shaojie Xu Yi Sui Jianlong Hu 《PloS one》2015,10(2)
Based on the hypothesis that the neighbors of disease genes trend to cause similar diseases, network-based methods for disease prediction have received increasing attention. Taking full advantage of network structure, the performance of global distance measurements is generally superior to local distance measurements. However, some problems exist in the global distance measurements. For example, global distance measurements may mistake non-disease hub proteins that have dense interactions with known disease proteins for potential disease proteins. To find a new method to avoid the aforementioned problem, we analyzed the differences between disease proteins and other proteins by using essential proteins (proteins encoded by essential genes) as references. We find that disease proteins are not well connected with essential proteins in the protein interaction networks. Based on this new finding, we proposed a novel strategy for gene prioritization based on protein interaction networks. We allocated positive flow to disease genes and negative flow to essential genes, and adopted network propagation for gene prioritization. Experimental results on 110 diseases verified the effectiveness and potential of the proposed method. 相似文献
996.
Yongqing Ding Yanjie Yang Xiuxian Yang Tiehui Zhang Xiaohui Qiu Xin He Wenbo Wang Lin Wang Hong Sui 《PloS one》2015,10(4)
Background
Burnout is recognized as an occupational hazard, and nursing has a high risk of burnout. This study aims to explore the relationship between psychological capital (PsyCap) and burnout among Chinese nurses and the mediating role of coping style in this relationship.Methods
A total of 1,496 nurses (effective response rate: 80.11%) from two large general hospitals in Daqing City of China were selected as participants. Data were collected via the Chinese Maslach Burnout Inventory (CMBI), the psychological capital questionnaire (PCQ-24), the Chinese Trait Coping Style Questionnaire (TCSQ) and demographic and caregiver-patient relationship. Hierarchical linear regression analyses were performed to explore the mediating role of positive coping and negative coping, and we used the Bootstrap method to confirm the mediating effect.Results
Self-efficacy, hope, resilience and optimism of nurses were all negatively related with emotional exhaustion, depersonalization and reduced personal accomplishment among Chinese nurses. Positive coping partially mediated the relationship between hope/optimism and emotional exhaustion and between self-efficacy/optimism and reduced personal accomplishment. Negative coping fully mediated the relationship between self-efficacy and emotional exhaustion, and in the regression model self-efficacy was positively correlated with emotional exhaustion. And negative coping also partially mediated the relationship between hope/optimism and emotional exhaustion and between optimism and depersonalization.Conclusion
PsyCap had effects on burnout and coping style was a mediator in this relationship among Chinese nurses. Nurses who had a strong sense of self-efficacy adopted more negative coping style, which in turn would lead to higher levels of emotional exhaustion. These findings shed light on the influence of negative coping on burnout, and positive coping was a positive resource for fighting against nurses’ burnout. Hence, in order to avoid negative coping style, improve skill of coping and enhance PsyCap of nurses, active interventions should be developed in the future. 相似文献997.
Bjarki Johannesson Lina Sui Donald O Freytes Remi J Creusot Dieter Egli 《The EMBO journal》2015,34(7):841-855
The discovery of insulin more than 90 years ago introduced a life‐saving treatment for patients with type 1 diabetes, and since then, significant progress has been made in clinical care for all forms of diabetes. However, no method of insulin delivery matches the ability of the human pancreas to reliably and automatically maintain glucose levels within a tight range. Transplantation of human islets or of an intact pancreas can in principle cure diabetes, but this approach is generally reserved for cases with simultaneous transplantation of a kidney, where immunosuppression is already a requirement. Recent advances in cell reprogramming and beta cell differentiation now allow the generation of personalized stem cells, providing an unlimited source of beta cells for research and for developing autologous cell therapies. In this review, we will discuss the utility of stem cell‐derived beta cells to investigate the mechanisms of beta cell failure in diabetes, and the challenges to develop beta cell replacement therapies. These challenges include appropriate quality controls of the cells being used, the ability to generate beta cell grafts of stable cellular composition, and in the case of type 1 diabetes, protecting implanted cells from autoimmune destruction without compromising other aspects of the immune system or the functionality of the graft. Such novel treatments will need to match or exceed the relative safety and efficacy of available care for diabetes. 相似文献
998.
Lin Yangyang Lu Xiao Dong Juntao He Xiaokuo Yan Tiebin Liang Huiying Sui Minghong Zheng Xiuyuan Liu Huihua Zhao Jingpu Lu Xinxin 《Neurochemical research》2015,40(9):1839-1848
Neurochemical Research - A rat model of vascular dementia was used to compare the effects of involuntary exercise induced by functional electrical stimulation (FES), forced exercise and voluntary... 相似文献
999.
Bajon A. M. Tsé High Yuen T. L. S. Li Sui Fong J. -C. Olah G. M. 《Biotechnology letters》1985,7(3):203-206
Summary Fourteen fungal strains were grown on sugar-beet pulp (SBP) in a semisolid state with the view of evaluating their capabilities in increasing the protein content of SBP. The highest increases were obtained withSporotrichum
thermophile no 89 Paprican andThielavia
terrestric ATCC 38088, which gave a protein content of 14.6% and 13.4% respectively after a 3-day culture or a net increase of 48% and 36% respectively over that of the unfermented SBP. 相似文献
1000.
从雷公藤限皮中分得两种三萜,鉴定为 polpunonic acid 和3β,30-二羟基齐墩果-Δ~(12)-烯-29羧酸甲酯,后者未见文献报道,命名为雷二羟酸甲酯。此外,分到雷公藤春碱,根据理化性质和光谱分析,推测化学结构为Ⅲ,药理试验表明其为免疫抑制剂,药敏试验对白血病细胞有抑制。 相似文献