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41.
正The prospects of stem cell therapy for retinal ganglion cell(RGC)degeneration in human:RGC degeneration is a common pathologic cause of glaucoma and optic neuropathies,which are the leading cause of irreversible blindness and visual impairment in developed countries,currently affecting more than 100 million people worldwide.Intraocular pressure lowering can slow down glaucoma progression in a proportion of patients.Also,there is still no effective therapy for optic neuropathies.Besides,the degenerated RGCs in glaucoma cannot be 相似文献
42.
Jin-Ming Cen Jie Cheng Qing-Yuan Xiong Bai-Qiang Mei Wei-Biao Cai Xi-Li Yang 《慢性疾病与转化医学(英文)》2015,1(2):105-109
ObjectiveThis study explores the correlation between plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) and coronary heart disease (CHD) by comparing the level of plasma Lp-PLA2 in the plasma of patients with different types of CHD.MethodsBlood samples were collected from 56 patients diagnosed with CHD by the Department of Cardiology of the First People''s Hospital of Foshan and 34 healthy subjects from February 2013 to January 2014. We measured the concentration of plasma Lp-PLA2 and determined the levels of total cholesterol (Tch), triglyceride (TG), apolipoprotein A1 (Apo-A1), apolipoprotein B (Apo-B), high density lipoprotein-cholesterol (HDL-c), low density lipoprotein-cholesterol (LDL-c), lipoprotein a (Lp(a)), glucose (Glu), and high-sensitivity C-reactive protein (hs-CRP). The concentration of plasma Lp-PLA2 in the healthy control group and each subgroup of CHD patients were compared and analyzed for correlations of plasma Lp-PLA2 between the patients in different CHD subgroups and several laboratory indicators.ResultsThe concentration of plasma Lp-PLA2 in each subgroup of CHD was significantly higher than in the control group (P < 0.05). The concentration of Lp-PLA2 in the unstable angina pectoris (UAP) group and acute myocardial infarction (AMI) group were significantly higher than in the stable angina pectoris (SAP) group (P < 0.05), and the concentration of plasma Lp-PLA2 in the AMI group was significantly higher than in the UAP group (P < 0.05). The concentration of plasma Lp-PLA2 in the CHD group merely showed a positive correlation (r = 0.493, P < 0.05) with the hs-CRP group, but the levels of Tch, TG, Apo-A1, Apo-B, HDL-c, LDL-c, Lp(a) and Glu did not.ConclusionsThe concentration of plasma Lp-PLA2 in patients with CHD was higher than that in the control group. The concentration of plasma Lp-PLA2 in the subgroups of CHD patients varied greatly from each other. The inflammatory response of atherosclerosis might be resulted from the synergy of plasma Lp-PLA2 and hs-CRP. 相似文献
43.
Zhihong Cen Yujie Guo Qing Kong Qiuxi Zhou Weifeng Wu 《International journal of clinical and experimental pathology》2015,8(1):830-835
Background: Interleukin-10 (IL-10)-producing B cells, a subset of regulatory B cells, play critical roles in autoimmune and infectious diseases. However, the role of IL-10-producing B cells in acute viral myocarditis (AVMC) remains unknown. Methods: BALB/c mice were intraperitoneally (i. p.) infected with coxsackievirus B3 (CVB3) to establish AVMC models (AVMC group), while control mice (control group) were treated with phosphate-buffered saline (PBS) i. p. According to the time after injection, the AVMC group mice or control group mice were randomly separated into 1 week and 2 week subgroup. Myocardial histopathological changes were observed by hematoxylin and eosin staining and the frequency of splenic IL-10-producing B cells was measured by flow cytometry. Results: Histopathologic examination of heart tissues showed that mice infected with CVB3 developed AVMC. Compared with control group, the frequency of splenic IL-10-producing B cells was increased significantly in the AVMC group, with the 1 week AVMC subgroup (3.58 ± 0.47%) higher than the 2 week AVMC subgroup (2.50 ± 0.42%) (all P < 0.05). Conclusions: IL-10-producing B cells are increased in CVB3-induced AVMC, indicating that IL-10-producing B cells may play an important role in the pathogenesis of CVB3-induced AVMC. 相似文献
44.
Cen Xiang Yuou Teng Chaoran Yao Xuehui Li Menglin Cao Xuzhe Li Guojun Pan Kui Lu Herv Galons Peng Yu 《RSC advances》2018,8(28):15366
Excessive accumulation of free radicals in the body can cause liver damage, aging, cancer, stroke, and myocardial infarction. Anastatin B, a skeletal flavonoid, was reported to have antioxidant and hepatoprotective effects. Anastatin B derivatives, compound 1 and 2, were synthesized by our group previously. In this study, their antioxidant activity and hepatoprotective mechanism were studied using chemical evaluation methods, a cellular model of hydrogen peroxide (H2O2)-induced oxidative damage, and a mouse model of carbon tetrachloride (CCl4)-induced liver injury. Results from the chemical evaluation suggested that both compounds had good antioxidant power and radical scavenging ability in vitro. MTT assay showed that both compounds had cytoprotective activity in H2O2-treated PC12 cells. Moreover, their hepatoprotective activities evaluated using a mouse model of CCl4-induced liver injury that compared with the model group, pretreatment with compound 1 and 2 significantly decreased alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), and malondialdehyde (MDA) levels; reduced the liver tissue damage; and increased glutathione content. However, compound 2 was a more effective hepatoprotectant than compound 1 was. Finally, the amount of TNF-α and cytochrome P450 2E1 (CYP2E1) were significantly downregulated in compound 1 and 2 pretreatment groups. Collectively, our findings demonstrate that both compounds have potential antioxidant activity and hepatoprotective effect in vitro and in vivo. Further chemo-biological study and investigation of the compounds'' enzymatic targets are ongoing.Excessive accumulation of free radicals in the body can cause liver damage, aging, cancer, stroke, and myocardial infarction. 相似文献
45.
Biological CO2 elimination by photosynthetic microalgae is a sustainable way to mitigate CO2 from flue gas and other sources. Computational fluid dynamics was used to simulate algal cell movement with an enhanced flashing light effect in a novel panel bioreactor with horizontal baffles. Calculation results showed that the light/dark (L/D) cycle period decreased by 17.5% from 17.1 s to 14.1 s and that the horizontal fluid velocity increased by 95% while horizontal baffles were used under a 0.02 vvm air aeration rate and a microalgal concentration of 0.85 g L−1. The probability of the L/D cycle period within 5–10 s increased from 27.9% to 43.6%, indicating a 56% increase when horizontal baffles existed. It was proved by experiments that the mass-transfer coefficient increased by 31% and the mixing time decreased by 13% under a 0.06 vvm air aeration rate when horizontal baffles were used, and the algal biomass yield increased by ∼51% along with the decrease in the L/D cycle period when horizontal baffles were used.Biological CO2 elimination by photosynthetic microalgae is a sustainable way to mitigate CO2 from flue gas and other sources. 相似文献
46.
This work aims to provide a comprehensive understanding of negative DC discharge under coal pyrolysis gas components (CO2, H2, N2, CH4, CO) and air. The characteristics of negative DC discharge were studied in a wire–cylinder configuration at an ambient temperature range of 20–600 °C by analyzing V–I characteristics, discharge photographs, and gas composition. With increasing temperature, corona onset voltage, spark breakdown voltage and operational voltage range for corona discharge decrease, but discharge current and electron current ratio increase. Discharge current of CO2 is higher than that of air due to the difference of electronegativity. During CO2 discharge, with the increase of output voltage, three types of discharge are successively observed, namely corona, glow and arc. However, during H2 discharge, only glow discharge is observed. Temperatures significantly affect the capability of CO to attach electrons. The discharge characteristic of CO is similar to the electronegative gas media at 20 °C and the non-electronegative gas media when the temperature exceeds 350 °C. Chemical reactions and carbon generation are observed during the CH4 and CO discharge process. The product of carbon filaments under the CH4 gas medium leads to discharge current volatility and short circuit. These results assist in understanding the property of ESP at high temperatures.This work aims to provide a comprehensive understanding of negative DC discharge under coal pyrolysis gas components (CO2, H2, N2, CH4, CO) and air. 相似文献
47.
48.
明胶酶A在急性白血病细胞中的表达及其临床意义 总被引:8,自引:0,他引:8
目的 探讨急性白血病 (AL)细胞中明胶酶A(MMP2 )的表达及其临床意义。方法 应用明胶酶谱法检测了 4 6例初治AL患者MMP2的表达 ,同时应用逆转录 PCR(RT PCR)测定了MMP2活化相关基因基质金属蛋白酶抑制剂 2 (TIMP2 )、基质金属蛋白酶 1(MT1 MMP)的表达 ,并在体外进行了白血病细胞株穿膜试验研究。结果 4 6例AL患者中 2 4例 (5 2 2 % )MMP2表达阳性 ,MMP2阳性组与阴性组发生髓外浸润的比例分别为 5 0 0 %和 18 2 % (P值均 <0 0 5 ) ;外周血幼稚细胞百分率分别为 (77 2 1± 13 9) %和 (6 2 95± 17 2 ) % (P值均 <0 0 1)。同时 4 6例AL患者中TIMP2、MT1 MMP阳性表达分别为 2 7例 (5 8 7% )、33例 (71 7% )。体外穿膜试验证实了MMP2对白血病细胞侵袭能力的影响。结论 活性MMP2可能参与白血病细胞从骨髓释出并浸润组织的过程 相似文献
49.
Kara R. Melmed Elizabeth Carroll Aaron S. Lord Amelia K. Boehme Koto Ishida Cen Zhang Jose L. Torres Shadi Yaghi Barry M. Czeisler Jennifer A. Frontera Ariane Lewis 《Journal of stroke and cerebrovascular diseases》2021,30(8):105870
ObjectivesSystemic inflammatory response syndrome (SIRS) and hematoma expansion are independently associated with worse outcomes after intracerebral hemorrhage (ICH), but the relationship between SIRS and hematoma expansion remains unclear.Materials and methodsWe performed a retrospective review of patients admitted to our hospital from 2013 to 2020 with primary spontaneous ICH with at least two head CTs within the first 24 hours. The relationship between SIRS and hematoma expansion, defined as ≥6 mL or ≥33% growth between the first and second scan, was assessed using univariable and multivariable regression analysis. We assessed the relationship of hematoma expansion and SIRS on discharge mRS using mediation analysis.ResultsOf 149 patients with ICH, 83 (56%; mean age 67±16; 41% female) met inclusion criteria. Of those, 44 (53%) had SIRS. Admission systolic blood pressure (SBP), temperature, antiplatelet use, platelet count, initial hematoma volume and rates of infection did not differ between groups (all p>0.05). Hematoma expansion occurred in 15/83 (18%) patients, 12 (80%) of whom also had SIRS. SIRS was significantly associated with hematoma expansion (OR 4.5, 95% CI 1.16 - 17.39, p= 0.02) on univariable analysis. The association remained statistically significant after adjusting for admission SBP and initial hematoma volume (OR 5.72, 95% CI 1.40 – 23.41, p= 0.02). There was a significant indirect effect of SIRS on discharge mRS through hematoma expansion. A significantly greater percentage of patients with SIRS had mRS 4-6 at discharge (59 vs 33%, p=0.02).ConclusionSIRS is associated with hematoma expansion of ICH within the first 24 hours, and hematoma expansion mediates the effect of SIRS on poor outcome. 相似文献
50.
Lei Mingxi Varghese Bino Hwang Darryl Cen Steven Lei Xiaomeng Desai Bhushan Azadikhah Afshin Oberai Assad Duddalwar Vinay 《Journal of digital imaging》2021,34(5):1156-1170
Journal of Digital Imaging - The image biomarkers standardization initiative (IBSI) was formed to address the standardization of extraction of quantifiable imaging metrics. Despite its effort,... 相似文献