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1.
目的:探究miR-145 对血管平滑肌细胞(VSMC)的生物活性及对SM22α mRNA 表达的作用。方法: VSMC分为3 组,增殖VSMC组( 增殖组)、增殖VSMC + 转染miR-145-NC 组( 空载体组)、增殖VSMC+转染 miR-145 组( 增殖转染组)。采用RT-PCR 检测VSMC中SM22α mRNA、miR-145 的表达;免疫印迹检测cyclin E、p27 蛋白水平;Transwell 小室检测VSMC侵袭能力;MTT检测VSMC活力;流式细胞术检测VSMC凋亡率。 结果:增殖组VSMC中SM22α mRNA、miR-145 水平与空载体组相比数值较为接近;与增殖组及空载体组相比, 增殖转染组VSMC中miR-145、SM22α mRNA 表达升高。增殖组VSMC中cyclin E、p27 蛋白水平与空载体组相 比无差异;增殖转染组cyclin E 蛋白水平低于空载体组、增殖组,p27 蛋白水平高于空载体组、增殖组。增殖组 VSMC迁移数量与空载体组相比无差异;增殖转染组VSMC迁移数量明显低于空载体组、增殖组。增殖组与空载 体组VSMC在不同时间点的OD 值均较为接近;增殖转染组OD 值在不同时间点均低于空载体组、增殖组。增殖 组VSMC凋亡率与空载体组数值接近,组间比较差距较小;增殖转染组VSMC凋亡率较空载体组和增殖组升高。 结论:过表达miR-145 通过促进SM22α 水平增加,抑制血管平滑肌细胞的增殖,并促进其凋亡。  相似文献   
2.
PurposeThe variation in the immune response to Bartonella spp. infection in humans remains unclear. The present study compares the expression of selected interleukins, cytokines and cathelicidin (LL-37) in rheumatology clinic patients suffering from musculoskeletal symptoms with healthy blood donors. The patients had previously been tested for the presence of Bartonella henselae antibodies.MethodsGene expression of LL-37, interleukin (IL)-2, IL-4, IL-6, IL-12, interferon-(IFN)-γ, and tumor necrosis factor (TNF-α)-α was determined in blood samples using quantitative Polymerase Chain Reaction (qPCR). Statistical analysis was prepared with STATISTICA.ResultsStatistically significant differences in the mRNA levels of the tested cytokines (IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-12; p<0.0001) were observed between the healthy controls and patients; however, no difference was observed for LL37 mRNA (p ?= ?0.1974). No significant differences in mRNA expression were observed between IgG in anti-Bartonella seropositive and seronegative individuals (p>0.05). The only significant differences between the Bartonella spp. DNA positive and negative patients, indicated by PCR, were observed for TNF-α and IL-12 mRNA (p ?= ?0.0045 and p ?= ?0.0255, respectively).ConclusionA broadly similar immune response to the tested cytokines was observed among the participants irrespective of anti-Bartonella spp. IgG seropositivity. However, the Bartonella DNA-positive participants demonstrated significantly lower expression of IL-12 and TNF-α mRNA; this may indicate that these bacteria have a suppressive influence on the immune system.  相似文献   
3.
Superior Mesenteric Artery (SMA) Syndrome is a rare condition characterized by compression of the third part of the duodenum between the aorta and superior mesenteric artery due to decreased angle between these two vessels due to loss of intervening pad of fat. Tuberculosis is one of the causes, and its association with it is rare. However, SMA syndrome with significant gastrointestinal symptoms in TB poses a greater challenge in management, particularly in dissemination. Strong clinical suspicion, timely diagnosis and appropriate antituberculosis therapy are the keys to successful management.  相似文献   
4.
戚利坤  王巍 《天津医药》2022,50(3):300-304
目的 探讨肿瘤坏死因子α诱导蛋白6(TNFαIP6)在胃癌中的表达及其与患者临床病理特征及预后的关系。方法 收集133例胃癌患者的临床病理资料及随访数据,通过免疫组化染色检测TNFαIP6在胃癌组织中的表达情况,分析TNFαIP6表达与胃癌临床病理特征的关系。绘制Kaplan-Meier生存曲线比较TNFαIP6高表达与低表达者的总生存率差异,采用Cox回归分析确定胃癌患者预后的影响因素。结果 133例患者中TNFαIP6高表达52例,低表达81例。低分化腺癌、Borrmann Ⅳ型、T3~T4期、M1期、淋巴结转移及血管侵犯患者TNFαIP6高表达的比例明显升高。生存分析显示,TNFαIP6高表达组5年总生存率较低表达组明显下降(56.5% vs. 82.9%,Log-rank χ2=12.404,P<0.01)。Cox多因素分析证实,T3~T4期(HR=2.291,95%CI:1.028~5.103)、M1期(HR=3.628,95%CI:1.421~9.260)及TNFαIP6高表达(HR=2.742,95%CI:1.265~5.945)是胃癌患者预后的独立危险因素(均P<0.05)。结论 TNFαIP6在胃癌组织中的高表达与肿瘤的侵袭性特征有关,是影响胃癌患者预后的一个独立标志物。  相似文献   
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6.

Background

The clinical presentation of ankylosing spondylitis (AS) differs between genders. Our aim was to investigate differences in disease activity, disease outcome and treatment response between male and female AS patients before and after starting tumor necrosis factor (TNF)-α inhibitors in daily clinical practice.

Methods

Patients from the Groningen Leeuwarden AS (GLAS) cohort who started TNF-α inhibitors and who had visits at baseline and after 3 months and/or 2years of follow-up were included.

Results

Of 254 included AS patients, 69% were male. At baseline, female patients scored significantly higher on BASDAI, ASDAS, and tender entheses than male patients. In contrast, CRP, swollen joints, and history of extra-articular manifestations were comparable between genders. Women experienced significantly worse physical function and QoL, whereas men showed significantly more kyphosis and spinal radiographic damage. After 3 months and 2years of follow-up, all clinical assessments improved significantly, with comparable mean change scores for female and male patients; mean 2-year change in BASDAI -2.7?vs. -2.7, ASDAS -1.50?vs. -1.68, tender entheses -2.4?vs. -1.4, CRP -8?vs. -8, BASFI -2.2?vs. -2.1 and ASQoL -5?vs. -4, respectively. Radiographic progression was significantly higher in male patients. Female patients switched more frequently to another TNF-α inhibitor during 2years of follow-up (32% vs. 14%).

Conclusion

Although female patients experienced higher disease activity, worse physical function and quality of life, and switched TNF-α inhibitors more often, clinical improvement during treatment with TNF-α inhibitors was comparable between genders. However, male patients showed more radiographic spinal damage after 2years.  相似文献   
7.
The contribution of the motor cortex to the semantic retrieval of verbs remains a subject of debate in neuroscience. Here, we examined whether additional engagement of the cortical motor system was required when access to verbs semantics was hindered during a verb generation task. We asked participants to produce verbs related to presented noun cues that were either strongly associated with a single verb to prompt fast and effortless verb retrieval, or were weakly associated with multiple verbs and more difficult to respond to. Using power suppression of magnetoencephalography beta oscillations (15–30 Hz) as an index of cortical activation, we performed a whole‐brain analysis in order to identify the cortical regions sensitive to the difficulty of verb semantic retrieval. Highly reliable suppression of beta oscillations occurred 250 ms after the noun cue presentation and was sustained until the onset of verbal response. This was localized to multiple cortical regions, mainly in the temporal and frontal lobes of the left hemisphere. Crucially, the only cortical regions where beta suppression was sensitive to the task difficulty, were the higher order motor areas on the medial and lateral surfaces of the frontal lobe. Stronger activation of the premotor cortex and supplementary motor area accompanied the effortful verb retrieval and preceded the preparation of verbal responses for more than 500 ms, thus, overlapping with the time window of verb retrieval from semantic memory. Our results suggest that reactivation of verb‐related motor plans in higher order motor circuitry promotes the semantic retrieval of target verbs.  相似文献   
8.
Many airports are surfaced with grooved Marshall-designed dense graded asphalt. Grooving is required to satisfy regulatory aircraft skid resistance requirements, but introduces the risk of groove-related distress, such as groove closure. Consequently, airports seek an ungrooved runway surface option that performs similarly to dense graded asphalt but allows grooving to be avoided. Stone mastic asphalt is the most viable ungrooved runway surface solution and has been used on runways in Europe and China. However, before being accepted as an ungrooved runway surface in Australia, stone mastic asphalt must be shown to meet regulatory runway aircraft skid resistance requirements, and to otherwise perform similarly to typical dense graded asphalt mixtures for runway surfacing, including deformation resistance, fatigue cracking resistance and durability. Based on laboratory performance-related testing, 10-mm and 14-mm sized stone mastic asphalt mixtures, produced with four different aggregate sources, were found to generally meet the airport asphalt performance requirements. The 14 mm mixture was found to perform better than the 10 mm mixture, particularly regarding surface macrotexture and deformation resistance. It was concluded that airports should consider 14 mm sized stone mastic asphalt as an ungrooved runway surface in the future.  相似文献   
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10.
目的:探究塞来昔布对膝关节炎大鼠肿瘤坏死因子α( TNF-α)信号通路及关节滑膜细胞的影响。方法: SD大鼠随机分为模型组、假手术组和治疗组,治疗组大鼠制作膝关节炎模型后给予塞来昔布进行治疗。通过 TUNEL 法、qRT-PCR 法、CCK-8 法、免疫印迹等方法检测3 组大鼠滑膜细胞凋亡情况、TNF-α mRNA表达含量、 TNF-α 蛋白含量、关节炎指数及细胞增殖情况。结果:模型组、治疗组、假手术组关节滑膜细胞凋亡率分别为 89.38%、46.84%、13.68%。模型组与假手术组、治疗组相比较,细胞凋亡率显著升高,治疗组细胞凋亡数量多 于假手术组。假手术组、治疗组细胞增殖OD值比模型组高,差异具有统计学意义,假手术组关节滑膜细胞的增 殖数量最多,模型组关节滑膜细胞的增殖数量最少,治疗组关节滑膜细胞的增殖情况比假手术组相比明显减少。 与假手术组、治疗组比较,模型组关节滑膜细胞中TNF-α 蛋白表达水平显著上升,治疗组TNF-α 蛋白表达水平较 假手术组明显升高。与假手术组、治疗组比较,模型组TNF-α mRNA含量显著升高,治疗组TNF-α mRNA表达 量较假手术组明显升高。治疗组和模型组大鼠关节炎指数相近,随着给药时间的增加,治疗组大鼠膝关节炎情况 逐渐好转,而未服用药物的模型组大鼠病情逐渐恶化。结论:塞来昔布胶囊治疗膝关节炎大鼠效果显著,能够显 著降低TNF-α 信号通路的表达水平,改善关节滑膜细胞的凋亡情况。  相似文献   
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