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21.
目的:观察补益营卫方对衰老表皮结构蛋白K17的基因和蛋白水平的影响。方法:将3个月龄小鼠(年轻组)与14个月龄小鼠(老年组)表皮细胞消化分离出来,然后进行传代培养,其中14个月龄小鼠(老年组)的表皮细胞分为2组,一组用常规方法培养细胞,另一组用含2.5%的补益营卫方培养基进行培养,采用荧光定量RT-PCR法和Western Blotting法分别检测细胞K17mRNA表达和细胞K17蛋白表达。结果:与年轻组比较,老年组的K17mRNA和蛋白表达水平均升高(P<0.05);经药物干预后小鼠表皮细胞中K17mRNA和蛋白水平较老年组明显降低(P<0.05)。结论:补益营卫方可通过抑制衰老表皮结构蛋白K17的表达,起到延缓皮肤衰老作用。 相似文献
22.
文题释义:杜仲:杜仲是中国传统的中药药材,其具有增加机体免疫性、强身健骨的疗效,研究表明杜仲可以促进成骨细胞的增殖并且可以促进骨组织的愈合。近年来对于杜仲的研究主要集中于其有效成分的提取及分析。
杜仲醇:是杜仲的主要有效成分之一,可以增强关节炎大鼠骨组织的强度,并且具有降血压以及促进伤口愈合的能力。
背景:目前关于杜仲的研究主要集中于其治疗骨关节炎能增强骨组织的愈合能力,但是关于杜仲对根尖周炎骨破坏的修复作用尚未见报道。
目的:探讨杜仲醇提取物对根尖周炎大鼠组织蛋白酶K的影响。
方法:选取24只SD大鼠随机分为根尖周炎组20只及对照组4只,根尖周炎组于右侧下颌第一磨牙开髓后建立根尖周炎模型,对照组不做任何处理。饲养4周后,取根尖周炎组及对照组各4只拍摄MICRO-CT,计算根尖周炎骨破坏量,确认大鼠根尖周炎动物模型构建成功。饲养第5周,将剩余16只根尖周炎大鼠随机分为杜仲醇提取物组及生理盐水组,每组8只,每天灌胃杜仲醇提取物5 mL/kg或等量生理盐水。灌胃4周后,每组取4只大鼠拍摄MICRO-CT,分析杜仲醇提取物对根尖周骨组织的修复能力,另外取4只大鼠采用免疫组化染色观察右下颌第一磨牙牙槽骨组织蛋白酶K的表达。
结果与结论:①MICRO-CT结果显示,对照组骨吸收体积为(0.223±0.009) mm3,根尖周炎组骨吸收体积为(0.945±0.037) mm3,两组骨吸收量比较差异有显著性意义(P=0.00),说明大鼠根尖周炎模型构建成功;②灌胃4周后,MICRO-CT结果显示杜仲醇提取物组骨吸收体积较灌胃前减小,差异有显著性意义(P < 0.05);③灌胃4周后,免疫组化结果显示杜仲醇提取物根尖周炎骨破坏标志因子组织蛋白酶K的表达较灌胃前降低,差异有显著性意义(P < 0.05);④结果表明,杜仲醇提取物可以抑制骨破坏标志因子组织蛋白酶K的表达,并且可以促进大鼠根尖周炎骨组织的愈合。
ORCID: 0000-0001-5450-7016(吴大雷)
中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程 相似文献
23.
Gholamreza Azizi Sanaz Afraei Reza Sedaghat Mir Hadi Seyedzadeh 《Food and Agricultural Immunology》2015,26(6):782-793
Experimental autoimmune encephalomyelitis (EAE) is a mouse model for multiple sclerosis (MS), in which an inflammatory demyelination and axonal damage occurs. Kombucha tea is a fermented beverage made from kombucha mushroom, brewed tea, and sugar. In recent years kombucha tea has attracted interest due to its pharmacological properties like antioxidant effects. The aim of the present research was to test the therapeutic effect of kombucha tea in EAE. We induced EAE model in 18 female C57BL/6 mice by inoculation of myelin oligodendrocyte glycoprotein-35-55 (MOG35-55) in complete Freund’s adjuvant emulsion. Then, in order to ameliorate EAE symptoms, we used kombucha tea. During the course of study clinical evaluation was assessed, and on the day 21 post-immunization, for evaluation of nitric oxide (NO), total antioxidants capacity and tumor necrosis factor-alpha (TNF-α), blood samples were taken from the heart of mice. The mice were sacrificed and brains and cerebellums of mice were removed for histological analysis. Our findings demonstrated that kombucha tea had beneficial effects on EAE by lower incidence, attenuation in the severity, and also a delay in the onset of disease. Histological analysis showed that inflammatory criteria including the number of infiltrated immune cells and plaques as well as demyelination in kombucha tea dosed mice were significantly lower than the control group. Also, in comparison with control mice, the serum levels of NO and TNF-α in kombucha tea-treated mice were significantly decreased. Kombucha tea with its potential therapeutic effects and immunomodulatory properties might be proposed, after additional necessary tests and trials, for treatment of MS. 相似文献
24.
Obesity exacerbates imiquimod‐induced psoriasis‐like epidermal hyperplasia and interleukin‐17 and interleukin‐22 production in mice 下载免费PDF全文
Kaori Kanemaru Ayano Matsuyuki Yoshikazu Nakamura Kiyoko Fukami 《Experimental dermatology》2015,24(6):436-442
Psoriasis is a chronic inflammatory skin disorder that is accompanied by an imbalance between the proliferation and differentiation of keratinocytes. A number of studies have suggested an association between obesity and severe psoriasis; however, it remains to be clarified whether obesity exacerbates psoriasis. To address this unsolved question, we induced psoriasiform dermatitis in mouse models for obesity. We found that obesity exaggerated the severity of psoriasiform dermatitis induced by topical application of the Toll‐like receptor (TLR) 7 agonist, imiquimod. Ear swelling and epidermal hyperplasia were more prominent in the obese mice than in the control mice. When compared to imiquimod‐treated control mice, imiquimod‐treated obese mice expressed higher levels of psoriasis mediators, interleukin‐17A (IL‐17A) and IL‐22 in the skin. Food intake restriction partially abrogated enhanced ear swelling and cytokine overproduction in obese mice. Furthermore, the obesity environment and imiquimod treatment synergistically induced an IL‐17A downstream molecule, regenerating islet‐derived 3γ (Reg3γ), which is a critical molecule for psoriatic epidermal hyperplasia. Palmitic acid, one of the fatty acids released by subcutaneous adipocytes, increased the expression of REG3A (a human homologue of mouse Reg3γ) in both the HaCaT keratinocyte cell line and normal human keratinocytes. Taken together, these results strongly suggest that obesity exacerbates psoriasiform dermatitis in mice by upregulating IL‐17A, IL‐22 and Reg3γ. 相似文献
25.
Viroporins are a group of low-molecular-weight proteins containing about 50–120 amino acid residues, which are encoded by animal viruses. Viroporins are involved in several stages of the viral life cycle, including viral gene replication and assembly, as well as viral particle entry and release. Viroporins also play an important role in the regulation of antiviral innate immune responses, especially in inflammasome formation and activation, to ensure the completion of the viral life cycle. By reviewing the research progress made in recent years on the regulation of the NLRP3 inflammasome by viroporins of animal viruses, we aim to understand the importance of viroporins in viral infection and to provide a reference for further research and development of novel antiviral drugs. 相似文献
26.
Robert E. Hurst Beverley Greenwood-Van Meerveld Amy B. Wisniewski Samuel VanGordon HsuehKung Lin Bradley P. Kropp Rheal A. Towner 《Translational andrology and urology》2015,4(5):563-571
The definition of interstitial cystitis (IC) has evolved over the years from being a well-defined entity characterized by diagnostic lesion (Hunner’s ulcer) in the urothelium to a clinical diagnosis by exclusion [painful bladder syndrome (PBS)]. Although the etiology is unknown, a central theme has been an association with increased permeability of the bladder. This article reviews the evidence for increased permeability being important to the symptoms of interstitial cystitis/painful bladder syndrome (IC/PBS) and in treating the disorder. Recent work showing cross-communication among visceral organs is also reviewed to provide a basis for understanding IC/PBS as a systemic disorder of a complex, interconnected system consisting of the bladder, bowel and other organs, nerves, cytokine-responding cells and the nervous system. 相似文献
27.
J Y Suh Woo H Shim Gyunggoo Cho Xiang Fan Seon J Kwon Jeong K Kim George Dai Xiaoying Wang Young R Kim 《Journal of cerebral blood flow and metabolism》2015,35(6):1033-1043
Vasoreactivity to hypercapnia has been used for assessing cerebrovascular tone and control altered by ischemic stroke. Despite the high prognostic potential, traits of hypercapnia-induced hemodynamic changes have not been fully characterized in relation with baseline vascular states and brain tissue damage. To monitor cerebrovascular responses, T2- and T2*-weighted magnetic resonance imaging (MRI) images were acquired alternatively using spin- and gradient-echo echo plannar imaging (GESE EPI) sequence with 5% CO2 gas inhalation in normal (n=5) and acute stroke rats (n=10). Dynamic relative changes in cerebrovascular volume (CBV), microvascular volume (MVV), and vascular size index (VSI) were assessed from regions of interest (ROIs) delineated by the percent decrease of apparent diffusion coefficient (ADC). The baseline CBV was not affected by middle cerebral artery occlusion (MCAO) whereas the baseline MVV in ischemic areas was significantly lower than that in the rest of the brain and correlated with ADC. Vasoreactivity to hypercapnic challenge was considerably attenuated in the entire ipsilesional hemisphere including normal ADC regions, in which unsolicited, spreading depression-associated increases of CBV and MVV were observed. The lesion-dependent inhomogeneity in baseline MVV indicates the effective perfusion reserve for accurately delineating the true ischemic damage while the cascade of neuronal depolarization is probably responsible for the hemispherically lateralized changes in overall neurovascular physiology. 相似文献
28.
Guowei Zhang Fenger Sun Heping Liu Xiaoyan Ren Hong Xu Mingjie Wang Yizheng Fu 《Materials》2021,14(9)
The structural properties, elastic anisotropy, electronic structures and work function of D022-type Al3TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al3Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D022-type Al3TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al3La is the strongest, while that of Al3Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young’s modulus are further explained by the work function. Finally, the experimental design proves that D022-Al3Ta has an excellent strengthening effect. 相似文献
29.
Improving the dietary quality of women and children is essential to reduce all forms of malnutrition. In this study, we assessed seasonal child and maternal dietary diversity and consumption of animal‐source foods (ASF), using 1,236 observations from combined data collected among 167 mother–child dyads in rural Timor‐Leste. We used generalized linear and logistic mixed‐effects models to examine the dietary differentials of mothers and children in two agricultural livelihood zones and across the seasons, as well as to identify household and agroecological characteristics associated with children's dietary quality in relation to their mothers'. We found dietary quality to be marginally better in coastal than in mid‐altitude zones. However, women's diets were strikingly poor, and their intake of ASF was lower than among children. Mothers exhibited preferential allocation patterns of specific ASF, dairy products and eggs, to children. The intake of ASF was predicted by seasonality. Flesh foods and red meat were much more likely to be consumed during the dry season, when cultural ceremonies are often performed. We found a positive and strongly significant association between children's dietary indicators—dietary diversity score, minimum dietary diversity and ASF consumption, and those of their mothers'. Maternal dietary quality and educational attainment, more so than agroecological characteristics, were explanatory factors of children's diet. Our study highlights that addressing the dietary quality of children in Timor‐Leste would benefit from improving women's diets through better access to nutritious foods and to secondary education. 相似文献
30.
目的探讨全身振动训练联合正弦交变电磁场对去卵巢骨质疏松大鼠骨密度、骨代谢、骨生物力学性能的影响。方法将100只大鼠随机分为切除卵巢组和对照组,分别进行卵巢切除术和假手术,大鼠进行6周恢复,恢复后将造模成功的切除卵巢大鼠随机分为模型组(MO组)、全身振动训练组(W组)、正弦交变电磁场组(S组)、全身振动训练+正弦交变电磁场组(WS组),对照组列为假手术组(SO组),进行为期16周干预,干预结束后对大鼠进行骨密度、骨代谢、骨生物力学性质的检测。结果16周干预完成后,MO组、S组大鼠体质量显著高于SO组、W组、WS组大鼠(P0. 05); W组、WS组、SO组大鼠骨密度指标、血清雌二醇浓度指标明显高于大鼠MO组(P0. 05); SO组大鼠血清雌二醇浓度指标明显高于S组、W组、WS组(P0. 05); M组大鼠血清OC、ALP浓度明显高于SO组、W组、S组、WS组大鼠(P0. 05);尿液DPD/Cre、Ca/Cre、P/Cre浓度方面,M组大鼠明显高于SO组、W组、S组、WS组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨断裂载荷组间无明显差异(P0. 05); SO组、W组、S组、WS组大鼠股骨弹性模量明显高于MO组大鼠(P0. 05)。SO组大鼠股骨弹性模量明显高于S组大鼠(P0. 05),但与W组、WS组大鼠没有明显差异(P0. 05)。L4椎体压缩试验,SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组大鼠高于S组、W组,差异有统计学意义(P0. 05),但与WS组大鼠没有明显差异(P0. 05)。结论全身振动训练、正弦交变电磁场、全身振动训练联合正弦交变电磁场3种干预方式施用于去卵巢骨质疏松大鼠均能提升骨密度、抑制骨吸收、平衡骨代谢、改善骨骼结构力学和材料力学性能。而全身振动训练联合正弦交变电磁场能的治疗效果优于单纯使用全身振动训练或正弦交变电磁场,在临床应用中有一定推广价值。 相似文献