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951.
Reactive oxygen species mediates a metabolic memory of high glucose stress signaling in bovine retinal pericytes 下载免费PDF全文
AIM: To investigate the role of reactive oxygen species (ROS) and antioxidant mechanism underlying the metabolic memory of bovine retinal pericytes (BRPs) induced by high glucose.
METHODS: Effects of high glucose levels and culture time on BRPs viability were evaluated by CCK-8. BRPs were grown in high-glucose media (30 mmol/L) for 4d followed by culture in normal glucose condition (5.6 mmol/L) for 4d in an experimental group. In contrast, in negative and positive control groups, BRPs were grown in either normal-glucose media or high-glucose media for 8d, respectively. The ROS levels, apoptosis, the expression and activity of manganese superoxide dismutase (MnSOD) in BRPs, as well as the protective effect of adeno-associated viral (AAV)-mediated over expression of MnSOD were determined separately by DCHFA, ELISA and Western blot.
RESULTS: Comparing the result of cells apoptosis, activity and protein expression of MnSOD and caspase-3, the cell culture system that exposed in sequence in 30 mmol/L and normal glucose for 4d was demonstrated as a suitable model of metabolic memory. Furthermore, delivery of antioxidant gene MnSOD can decrease BRPs apoptosis, reduce activated caspase-3, and reverse hyperglycemic memory by reducing the ROS of mitochondria.
CONCLUSION: Increased ROS levels and decreased MnSOD levels may play important roles in pericyte loss of diabetic retinopathy. BRPs cultured in high glucose for 4d followed by normal glucose for 4d could be an appropriate model of metabolic memory. rAAV-MnSOD gene therapy provides a promising strategy to inhibit this blinding disease. 相似文献
952.
Arhanti Sadanand Ahmed Aljudi D. John Bergsagel Frank G. Keller 《Pediatric blood & cancer》2023,70(6):e30283
Background
Progressive transformation of germinal centers (PTGC) is a rare diagnosis characterized by asymptomatic lymph node enlargement. It has previously been associated with lymphoma, autoimmune conditions, and lymphoproliferative diseases in small pediatric case series.Procedures
We conducted a single-center retrospective review of pediatric cases of PTGC diagnosed at our institution by hematopathologists from 2000 to 2020.Results
We identified 57 primary cases and three recurrent cases of PTGC. Laboratory and imaging evaluations were obtained inconsistently. Nine patients (16%) saw a pediatric hematology/oncology (PHO) specialist prior to diagnosis, and 21 (37%) had follow-up with PHO after diagnosis.Conclusions
Patients with PTGC had similar age and involved lymph node sites to those from previous case series. Fewer patients underwent recurrent lymph node biopsy than previously described. PTGC has been linked to certain types of lymphoma, although never definitively associated with lymphoma. Follow-up with a PHO provider is indicated to ensure that close surveillance is performed. 相似文献953.
目的研究姜黄素(Cur)对过氧化氢(H2O2)诱导小鼠巨噬细胞内一氧化氮(NO)及活性氧(ROS)生成的影响。方法健康6~8周龄昆明种小鼠腹腔提取巨噬细胞,培养成活后调整细胞水平为2×108L-1,H2O2组加入1 mmol.L-1H2O2刺激30 min,Cur干预组加入不同水平Cur,作用细胞2 h后加入1 mmol.L-1H2O2刺激30 min,对照组加入等量9 g.L-1盐水。免疫细胞化学法观察诱导型一氧化氮合酶(iNOS)的表达,Griess法测定上清液NO的生成量,荧光探针DCFH-DA法测定巨噬细胞内ROS生成。结果对照组上清液NO2-水平(相当于NO累积生成量)很低,H2O2组显著高于对照组(P<0.01),不同水平Cur干预组NO2-水平降低,即NO表达减少,并且呈水平依赖性降低(P<0.05)。各组胞质内iNOS表达与上清液NO的生成量呈相应的变化趋势。H2O2组小鼠巨噬细胞内ROS显著升高,与对照组比较差异有统计学意义(P<0.01)。不同水平Cur预先干预2 h后,ROS生成量呈水平依赖性降低(P<0.01)。结论Cur抑制H2O2诱导的小鼠巨噬细胞内NO生成,可能是通过抑制iNOS... 相似文献
954.
Wiparat Manuyakorn Chalerat Direkwattanachai Suwat Benjaponpitak Wasu Kamchaisatian Cherapat Sasisakulporn Wanlapa Teawsomboonkit 《Pediatrics international》2010,52(1):118-125
Background: Dry powder inhalers (DPI) are alternative devices for delivering medication for treatment of asthma. The amount of drug delivery to the lungs is directly influenced by peak inspiratory flow rate (PIFR). A minimum PIFR of −30 L/min is needed for the Turbuhaler and Accuhaler.
Methods: In order to evaluate the sensitivity of the Turbutester and Accuhaler tester in detecting the minimum and optimum PIFR for the Turbuhaler and Accuhaler in asthmatic children, PIFR was measured using the In-Check Dial through the internal resistance of the Turbuhaler and Accuhaler and compared according to the child's ability to make a whistle sound via both testers.
Results: A total of 259 asthmatic children were studied: 20 pre-school children, aged 5–6 years; 174 school-age children, aged 7–12 years; and 65 adolescents, aged 13–18 years. The sensitivity of the Turbutester and Accuhaler tester to detect optimum PIFR were 98.40% and 97.2%, respectively. In the comparison among age groups, the sensitivity of the Accuhaler tester to detect optimum or minimum PIFR for the Accuhaler was 95%, 97.7% and 95.4%, respectively. The sensitivity of the Turbutester to detect optimum PIFR for the Turbuhaler was 94.4%, 98.8% and 98.5%, respectively. The sensitivity of the Turbutester to detect minimum PIFR for the Turbuhaler was 94.7%, 100% and 100%, respectively. There were no significant differences in percentage of having optimum or minimum PIFR among asthma severity and current device usage in all age groups.
Conclusions: Most children aged at least 5 years could generate enough PIFR to use dry powder inhaler devices. Both the Turbutester and Accuhaler tester were found to have high sensitivity in detecting optimum and minimum required PIFR. 相似文献
Methods: In order to evaluate the sensitivity of the Turbutester and Accuhaler tester in detecting the minimum and optimum PIFR for the Turbuhaler and Accuhaler in asthmatic children, PIFR was measured using the In-Check Dial through the internal resistance of the Turbuhaler and Accuhaler and compared according to the child's ability to make a whistle sound via both testers.
Results: A total of 259 asthmatic children were studied: 20 pre-school children, aged 5–6 years; 174 school-age children, aged 7–12 years; and 65 adolescents, aged 13–18 years. The sensitivity of the Turbutester and Accuhaler tester to detect optimum PIFR were 98.40% and 97.2%, respectively. In the comparison among age groups, the sensitivity of the Accuhaler tester to detect optimum or minimum PIFR for the Accuhaler was 95%, 97.7% and 95.4%, respectively. The sensitivity of the Turbutester to detect optimum PIFR for the Turbuhaler was 94.4%, 98.8% and 98.5%, respectively. The sensitivity of the Turbutester to detect minimum PIFR for the Turbuhaler was 94.7%, 100% and 100%, respectively. There were no significant differences in percentage of having optimum or minimum PIFR among asthma severity and current device usage in all age groups.
Conclusions: Most children aged at least 5 years could generate enough PIFR to use dry powder inhaler devices. Both the Turbutester and Accuhaler tester were found to have high sensitivity in detecting optimum and minimum required PIFR. 相似文献
955.
956.
Elizabeth M.F.L. Domingues Teresa Matuck Miguel L. Graciano Edison Souza Suzimar Rioja Mônica C. Falci Deise B. Monteiro de Carvalho Luís Cristóvão Porto 《Clinical transplantation》2010,24(6):821-829
Domingues EMFL, Matuck T, Graciano ML, Souza E, Rioja S, Falci MC, Monteiro de Carvalho DB, Porto LC. Panel reactive HLA antibodies, soluble CD30 levels, and acute rejection six months following renal transplant. Clin Transplant 2010: 24: 821–829. © 2009 John Wiley & Sons A/S. Abstract: Background: Specific anti‐human leukocyte antigen antibodies (HLA) in the post‐transplant period may be present with acute rejection episodes (ARE), and high soluble CD30 (sCD30) serum levels may be a risk factor for ARE and graft loss. Methods: HLA cross‐matching, panel reactive antibodies (PRA), and sCD30 levels were determined prior to transplantation in 72 patients. Soluble CD30 levels and PRA were re‐assessed at day 7, 14, 21, and 28, and monthly up to the sixth. Results: Twenty‐four subjects had a positive PRA and 17 experienced ARE. Nine of 17 ARE subjects demonstrated positive PRA and 16 had HLA mismatches. Positive PRA was more frequent in ARE subjects (p = 0.03). Eight subjects with ARE had donor‐specific antibodies (DSA) in serum samples pre‐transplantation, two subjects developed DSA. Three subjects without ARE had positive PRA only in post‐transplantation samples. Soluble CD30 levels were higher in pre‐transplant samples and ARE subjects than non‐ARE subjects (p = 0.03). Post‐transplant sCD30 levels were elevated in subjects who experienced rejection and were significantly higher at seven d (p = 0.0004) and six months (p = 0.03). Conclusions: Higher sCD30 levels following transplant were associated with ARE. Elevated sCD30 levels may represent a risk factor for acute rejection. 相似文献
957.
目的考察国内生产的抗生素类注射用无菌粉末和小容量注射液中不溶性微粒的质量。方法用GW J-4型智能微粒检测仪按《中国药典》光阻法进行测定。结果293批次样品仅有1批不溶性微粒检查结果不符合2005年版《中国药典》规定。结论国产抗生素类注射用无菌粉末和小容量注射液不溶性微粒检查结果令人满意。 相似文献
958.
蒙脱石散对盐酸左氧氟沙星体外吸附的影响 总被引:7,自引:0,他引:7
目的: 探讨蒙脱石散对盐酸左氧氟沙星体外吸附的影响.方法: 采用不同剂量的盐酸左氧氟沙星分别与3 g蒙脱石散混合,加入0.1 mol·L-1盐酸溶液中,在(37±0.5)℃水浴中恒温2 h后过滤,用紫外分光光度法测定盐酸左氧氟沙星的含量变化.结果: 蒙脱石散对盐酸左氧氟沙星的吸附率为(98.37±0.03)%.结论: 蒙脱石散对盐酸左氧氟沙星有极强吸附,因此应避免两种药物同时服用. 相似文献
959.
同型半胱氨酸和超敏C反应蛋白与冠心病的相关性分析 总被引:2,自引:0,他引:2
杨文娟 《菏泽医学专科学校学报》2010,22(2):18-20
目的探讨同型半胱氨酸(Hcy)和超敏C-反应蛋白(hs-CRP)的血清水平在监测冠心病病情方面的作用及与冠状动脉病变程度的关系。方法冠心病患者118例,按临床诊断分为急性心肌梗塞(AMI)组40例、不稳定性心绞痛(UAP)组36例、稳定性心绞痛(SAP)组42例,对照组40例。测定hs-CRP、同型半胱氨酸(Hcy)的水平,比较各组间的差异。结果 AMI组、UAP组及SAP组的Hcy和hs-CRP水平均比对照组高,差异有显著性(P〈0.05);AMI组、UAP组和SAP组Hcy和hs-CRP水平相比,差异有显著性(P〈0.05);Hcy和hs-CRP水平变化呈正相关。结论血清Hcy和hs-CRP可能是冠状动脉粥样硬化的标志,参与了冠心病的发病过程,其数值与冠状动脉病变程度密切相关。 相似文献
960.
柚皮苷抑制高糖诱导的脐静脉内皮细胞与单核细胞的粘附作用 总被引:2,自引:0,他引:2
目的研究柚皮苷对高糖诱导的脐静脉内皮细胞(HUVECs)与单核细胞的粘附的抑制作用及机制。方法分离培养HUVECs后,采用不同剂量的柚皮苷预处理HUVECs,然后高糖诱导HUVECs;加入荧光染料标记单核细胞系THP-1细胞与HUVECs共同孵育,荧光显微镜下观察HUVECs与单核细胞的粘附作用并拍照,比较粘附密度;提取总蛋白后,Western blotting检测处理后HUVECs粘附分子的表达;荧光染料结合法检测处理后HUVECs活性氧的产生;提取处理的脐静脉内皮细胞核蛋白后,Western blotting检测核因子-κB在核内的量。结果高糖诱导HUVECs与单核细胞的粘附,柚皮苷可显著抑制高糖诱导的HUVECs与单核细胞的粘附。柚皮苷抑制高糖诱导的HUVECs细胞间粘附分子和血管内皮细胞粘附分子的表达,柚皮苷抑制高糖诱导的HUVECs活性氧产生,柚皮苷抑制高糖诱导的HUVECs核因子-κBp65活化。结论柚皮苷可能通过抑制高糖诱导的HUVECs活性氧产生,从而抑制核因子-κB的活化,进一步抑制细胞间粘附分子和血管内皮细胞粘附分子的表达,影响HUVECs与THP-1细胞的粘附,从而抑制高糖诱导的血管炎症... 相似文献