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991.
Jay Ronel V. Conejos Jalil Ghassemi Nejad Jung-Eun Kim Jun-Ok Moon Jae-Sung Lee Hong-Gu Lee 《International journal of molecular sciences》2021,22(5)
The objective of this study was to investigate the effects of supplementing with L-tryptophan (L-Trp) on milk protein synthesis using an immortalized bovine mammary epithelial (MAC-T) cell line. Cells were treated with 0, 0.3, 0.6, 0.9, 1.2, and 1.5 mM of supplemental L-Trp, and the most efficient time for protein synthesis was determined by measuring cell, medium, and total protein at 0, 24, 48, 72, and 96 h. Time and dose tests showed that the 48 h incubation time and a 0.9 mM dose of L-Trp were the optimal values. The mechanism of milk protein synthesis was elucidated through proteomic analysis to identify the metabolic pathway involved. When L-Trp was supplemented, extracellular protein (medium protein) reached its peak at 48 h, whereas intracellular cell protein reached its peak at 96 h with all L-Trp doses. β-casein mRNA gene expression and genes related to milk protein synthesis, such as mammalian target of rapamycin (mTOR) and ribosomal protein 6 (RPS6) genes, were also stimulated (p < 0.05). Overall, there were 51 upregulated and 59 downregulated proteins, many of which are involved in protein synthesis. The results of protein pathway analysis showed that L-Trp stimulated glycolysis, the pentose phosphate pathway, and ATP synthesis, which are pathways involved in energy metabolism. Together, these results demonstrate that L-Trp supplementation, particularly at 0.9 mM, is an effective stimulus in β-casein synthesis by stimulating genes, proteins, and pathways related to protein and energy metabolism. 相似文献
992.
993.
994.
Ming-Hui Yang Yi-Ming Arthur Chen Shan-Chen Tu Pei-Ling Chi Kuo-Pin Chuang Chin-Chuan Chang Chiang-Hsuan Lee Yi-Ling Chen Che-Hsin Lee Cheng-Hui Yuan Yu-Chang Tyan 《International journal of molecular sciences》2021,22(6)
Glycine N-methyltransferase (GNMT) regulates S-adenosylmethionine (SAMe), a methyl donor in methylation. Over-expressed SAMe may cause neurogenic capacity reduction and memory impairment. GNMT knockout mice (GNMT-KO) was applied as an experimental model to evaluate its effect on neurons. In this study, proteins from brain tissues were studied using proteomic approaches, Haemotoxylin and Eosin staining, immunohistochemistry, Western blotting, and ingenuity pathway analysis. The expression of Receptor-interacting protein 1(RIPK1) and Caspase 3 were up-regulated and activity-dependent neuroprotective protein (ADNP) was down-regulated in GNMT-KO mice regardless of the age. Besides, proteins related to neuropathology, such as excitatory amino acid transporter 2, calcium/calmodulin-dependent protein kinase type II subunit alpha, and Cu-Zn superoxide dismutase were found only in the group of aged wild-type mice; 4-aminobutyrate amino transferase, limbic system-associated membrane protein, sodium- and chloride-dependent GABA transporter 3 and ProSAAS were found only in the group of young GNMT-KO mice and are related to function of neurons; serum albumin and Rho GDP dissociation inhibitor 1 were found only in the group of aged GNMT-KO mice and are connected to neurodegenerative disorders. With proteomic analyses, a pathway involving Gonadotropin-releasing hormone (GnRH) signal was found to be associated with aging. The GnRH pathway could provide additional information on the mechanism of aging and non-aging related neurodegeneration, and these protein markers may be served in developing future therapeutic treatments to ameliorate aging and prevent diseases. 相似文献
995.
Eugene Choi Sung Jean Park Gunhee Lee Seung Kew Yoon Minho Lee Suk Kyeong Lee 《International journal of molecular sciences》2021,22(6)
Hepatocellular carcinoma (HCC), the most common malignant tumor in the liver, grows and metastasizes rapidly. Despite advances in treatment modalities, the five-year survival rate of HCC remains less than 30%. We sought genetic mutations that may affect the oncogenic properties of HCC, using The Cancer Genome Atlas (TCGA) data analysis. We found that the GNAQ T96S mutation (threonine 96 to serine alteration of the Gαq protein) was present in 12 out of 373 HCC patients (3.2%). To examine the effect of the GNAQ T96S mutation on HCC, we transfected the SK-Hep-1 cell line with the wild-type or the mutant GNAQ T96S expression vector. Transfection with the wild-type GNAQ expression vector enhanced anchorage-independent growth, migration, and the MAPK pathways in the SK-Hep-1 cells compared to control vector transfection. Moreover, cell proliferation, anchorage-independent growth, migration, and the MAPK pathways were further enhanced in the SK-Hep-1 cells transfected with the GNAQ T96S expression vector compared to the wild-type GNAQ-transfected cells. In silico structural analysis shows that the substitution of the GNAQ amino acid threonine 96 with a serine may destabilize the interaction between the regulator of G protein signaling (RGS) protein and GNAQ. This may reduce the inhibitory effect of RGS on GNAQ signaling, enhancing the GNAQ signaling pathway. Single nucleotide polymorphism (SNP) genotyping analysis for Korean HCC patients shows that the GNAQ T96S mutation was found in only one of the 456 patients (0.22%). Our data suggest that the GNAQ T96S hotspot mutation may play an oncogenic role in HCC by potentiating the GNAQ signal transduction pathway. 相似文献
996.
为了研究焊接细节对钢结构超低周疲劳性能的影响,以T型接头为对象,在通用有限元程序Abaqus平台上,开发基于Arlequin算法的结构多尺度计算程序. 利用多尺度算法,开展焊接接头的局部弹塑性有限元分析. 比较焊趾半径、厚钢板未熔透长度及焊趾表面凹凸对局部塑性应变履历的影响,利用Coffin-Manson模型对T型接头的超低周疲劳特性进行定性讨论. 数值计算结果表明,焊趾位置是焊接接头的超低周疲劳易损位置,厚钢板的未熔透长度对焊接部位局部塑性应变的影响不大;焊趾半径对焊趾局部塑性应变有较大的影响,增大焊趾半径可以有效提升钢结构在循环荷载下的超低周疲劳性能;焊趾表面的平整性是影响焊趾局部塑性应变履历的重要因素,尖锐的凹坑会明显降低焊接接头的超低周疲劳性能,磨平的焊趾表面可以减少局部塑性应变,提高接头的超低周疲劳强度. 相似文献
997.
针对工业大麻收割机茎秆切割效率低、输送率低,以及关键作业参数研究空白的现状,本文结合工业大麻茎秆物理特性,运用中心组合试验设计理论开展关键部件作业参数试验与优化,重点研究工业大麻收割机切割-输送作业关键参数中切割速度、链条输送速度、切割位置与夹持点水平间距对切割效率、输送率的影响规律,并以切割效率、输送率为响应指标进行多目标优化.首先对主产区工业大麻茎秆物理和机械力学特性进行研究,并进行与收割相关的物理参数测定,然后采用二次正交旋转组合试验方法设计试验,并用Design-Expert进行数据处理,建立切割效率、输送率的回归数学模型并进行方差分析.通过响应曲面方法分析各因素交互作用对切割效率、输送率的影响,并根据优化目标的重要程度(输送率较切割效率更重要)对回归模型进行多目标优化,得出工业大麻收割机切割-输送关键作业参数的最优组合如下:切割速度为1.33 m/s,链条输送速度为1.35 m/s,切割与夹持点水平距离为63.9 mm.此时切割效率最高、输送率最高,其值分别为44.35株/s、93.93%.最优参数组合下田间试验切割效率为44.7株/s、输送率为92.21%,作业性能大幅提升,达到了较为理想的效果. 相似文献
998.
甄诚 《安徽电气工程职业技术学院学报》2021,26(1):68-76
DCS系统调试的质量与机组顺利投产和安全运行紧密相关。新建火电机组DCS系统逻辑组态由于多方面原因往往存在着单点保护、与设备不契合、延时设置错误、功能缺陷等问题。文章结合调试期间实际典型案例对DCS逻辑组态的优化与修改进行归纳总结,为基建机组逻辑设计与调试提供参考。 相似文献
999.
1000.
使用文献研究法、比较研究法等方法,通过国内外税务部门绩效考评方法对比、国内各省市税务部门的横向对比,以及国内税务部门的所使用的各种绩效考评方式的纵向对比,找出新旧绩效制度传承、变革等方面的脉络,探索优化税务局绩效考评体系。 相似文献