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11.
Because retinitis pigmentosa (RP) has been shown to cause degenerative changes in the entire visual pathway, there is an urgent need to perform longitudinal assessments of RP-induced degeneration and identify imaging protocols to detect this degeneration as early as possible. In this study, we assessed a transgenic rat model of RP by using complementary noninvasive magnetic resonance imaging techniques, namely, proton magnetic resonance spectroscopy (1H-MRS), to investigate the metabolic changes in RP. Our study demonstrated decreased concentrations and ratios to creatine (Cr) of N-acetylaspartate (NAA), glutamate (Glu), γ-aminobutyric acid (GABA), and taurine (Tau), whereas myo-inositol (Ins) and choline (Cho) were increased in the visual cortex of Royal College of Surgeons (RCS) rats compared with control rats (p < 0.05). Furthermore, with the progression of RP, the concentrations of NAA, Glu, GABA, and Tau, and the ratios of GABA/Cr and Tau/Cr significantly decreased over time, whereas the concentrations of Ins and Cho and the ratio of Ins/Cr significantly increased over time (p < 0.05). In addition, in RCS rats, NAA/Cr decreased significantly from 3 to 4 months postnatal (p < 0.001), and Cho/Cr increased significantly from 4 to 5 months postnatal (p = 0.005). Meanwhile, the 1H-MRS indicators in 5-month postnatal RCS rats could be confirmed by immunohistochemical staining. In conclusion, with the progression of RP, the metabolic alterations in the visual cortex indicated progressive reprogramming with the decrease of neurons and axons, accompanied by the proliferation of gliocytes.  相似文献   
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目的 分析原发性闭角型青光眼合并视网膜色素变性患者的临床特征。 方法 本研究纳入2013年4月至2017年4月于首都医科大学附属北京同仁医院眼科中心住院治疗的原发性闭角型青光眼(primary angle closure glaucoma ,PACG)合并视网膜色素变性(retinitis pigmentosa,RP)患者32例,和同期入院的不合并RP的PACG患者229例。根据青光眼类型将其分为4组,急性闭角型青光眼合并RP组(acute angle closure glaucoma with retinitis pigmentosa, AACG-RP)12例、慢性闭角型青光眼合并RP组(chronic angle closure glaucoma with retinitis pigmentosa, CACG-RP)20例、急性闭角型青光眼不合并RP组(AACG-non RP)94例、慢性闭角型青光眼不合并RP组(CACG-non RP)135例,比较4组患者的发病年龄和眼轴长度等参数。 结果 患者平均发病年龄AACG-RP组(39.00±12.07)岁、CACG-RP组(43.85±12.79)岁、AACG-non RP组(66.44±9.40)岁、CACG-non RP组(63.95±10.42)岁,4组之间差异有统计学意义(F=47.70,P<0.05)。患者平均眼轴长度AACG-RP组(21.31±1.37)mm、CACG-RP组(22.33±1.09)mm、AACG-non RP组(22.31±1.03)mm、CACG-non RP组(22.47±1.01)mm,4组之间差异有统计学意义(F=19.09,P<0.05)。 结论 原发性闭角型青光眼患者合并视网膜色素变性患者中,急性闭角型青光眼患者较慢性闭角型青光眼患者发病更早,眼轴更短。原发性闭角型青光眼合并视网膜色素变性患者,尤其是急性闭角型青光眼合并视网膜色素变性患者较无视网膜色素变性者发病年龄更早,且眼轴更短。  相似文献   
14.
中医思维传承中国古代哲学的辩证思维传统,以独特的视角、方式和方法研究人类健康、生命及其疾病现象,表现出中华民族特有的原创思维特征。传承中医思维是坚定中医药文化自信的历史逻辑,创新中医思维是坚定中医药文化自信的理论逻辑,养成中医思维是坚定中医药文化自信的实践逻辑。中医药院校必须改革创新培养路径,培养出具有中医思维自觉的“铁杆”中医人才。  相似文献   
15.
Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury.  相似文献   
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Colorectal cancer (CRC) is one of the top three most deadly cancers despite using chemotherapy based on oxaliplatin or irinotecan combined with targeted therapy. Chiauranib has recently been identified to be a promising anticancer candidate with impressive efficacy and safety. However, the role and molecular mechanisms of Chiauranib in the treatment of CRC remain to be elucidated. Our study shows that Chiauranib inhibits cell proliferation and induces apoptosis in KRAS wild-type CRC cells in a dose- and time-dependent manner, but not mutation ones. Meanwhile, Chiauranib increases ROS production in KRAS wild-type CRC cells. Moreover, Chiauranib selectively suppresses KRAS wild-type CRC cells growth in vivo. Mechanistically, Chiauranib inhibits KRAS wild-type CRC cells by triggering ROS production via activating the p53 signaling pathway. Further, KRAS mutation CRC cells are resistant to Chiauranib by increasing Nrf2 to stably elevate the basal antioxidant program and thereby lower intracellular ROS induced by Chiauranib. Our findings provide the rationale for further clinical evaluation of Chiauranib as a therapeutic agent in treating KRAS wild-type CRC.  相似文献   
18.
Chemical investigation of the stem bark of Ficus tsiangii led to the isolation of a new coumarin ficuscoumarin (1) and a new norlignan ficuslignan (2) by chromatographic methods. Their structures were elucidated on the basis of spectroscopic analyses.  相似文献   
19.
It is widely accepted that redox reprogramming participates in malignant transformation of lung adenocarcinoma (LUAD). However, the source of excessive reactive oxygen species (ROS) and the downstream signaling regulatory mechanism are complicated and unintelligible. In the current study, we newly identified the aquaporin 3 (AQP3) as a LUAD oncogenic factor with capacity to transport exogenous hydrogen peroxide (H2O2) and increase intracellular ROS levels. Subsequently, we demonstrated that AQP3 was necessary for the facilitated diffusion of exogenous H2O2 in LUAD cells and that the AQP3-dependent transport of H2O2 accelerated cell growth and inhibited rapamycin-induced autophagy. Mechanistically, AQP3-mediated H2O2 uptake increased intracellular ROS levels to inactivate PTEN and activate the AKT/mTOR pathway to subsequently inhibit autophagy and promote proliferation in LUAD cells. Finally, we suggested that AQP3 depletion retarded subcutaneous tumorigenesis in vivo and simultaneously decreased ROS levels and promoted autophagy. These findings underscore the importance of AQP3-induced oxidative stress in malignant transformation and suggest a therapeutic target for LUAD.  相似文献   
20.
目的:回顾性分析恩度联合多西他赛序贯腹腔灌注治疗胃癌伴恶性腹水的疗效及不良反应。方法:收集72例胃癌伴腹水患者,曾接受过二线及以上方案化疗,观察组35例,采用恩度45 mg联合多西他赛35 mg/m2 d1,d5序贯腹腔灌注1周期;对照组37例,采用多西他赛35 mg/m2 d1,d5腹腔灌注1周期,统计患者腹水控制有效率、KPS改善率、腹水控制时间及不良反应。结果:治疗组中腹水控制有效率71.43%;对照组中腹水控制有效率48.65%,P=0.049,两组具有统计学差异;治疗组中KPS改善率77.14%,对照组中KPS改善率54.05%,P=0.04,两组具有统计学差异;观察组中腹水控制时间8~90天,中位控制时间44天,对照组中腹水控制时间5~66天,中位控制时间28天,两组控制时间比较,P=0.048,具有统计学差异;III级以上不良反应发生率低,无治疗相关性死亡,两组不良反应比较,P>0.05,无统计学差异。结论:恩度联合多西他赛序贯腹腔灌注治疗体力状况(performance status,PS)评分较差的胃癌伴恶性腹水患者,腹水控制较好,能明显提高患者生活质量,未见明显不良反应。  相似文献   
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