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991.
Guoliang Wang Xiaoyan Liu Liukun Meng Shenghua Liu Li Wang Jun Li Chuanjue Cui Jian Meng Shengshou Hu Yingjie Wei 《International journal of biological sciences》2014,10(7):798-806
A key feature of pulmonary hypertension (PH) is the remodeling of small pulmonary arteries due to abnormal pulmonary artery smooth muscle cell (PASMC) proliferation and resistance to apoptosis. However, the cellular mechanisms underlying how PASMCs in the pathological condition of pulmonary hypertension become resistant to apoptosis remain unknown. It was recently reported that lipocalin 2 (Lcn2) is up-regulated in a wide array of malignant conditions, which facilitates tumorigenesis partly by inhibiting cell apoptosis. In this study, we observed that the expression levels of Lcn2 were significantly elevated in a rat PH model induced with monocrotaline and in patients with congenital heart disease-associated PH (CHD-PH) when compared with respective control. Therefore, we hypothesize that Lcn2 could regulate human PASMC (HPASMC) apoptosis through a mechanism. By the detection of DNA fragmentation using the TUNEL assay, the detection of Annexin V/PI-positive cells using flow cytometry, and the detection of cleaved caspase-3 and caspase-3 activity, we observed that Lcn2 significantly inhibited HPASMC apoptosis induced by serum withdrawal and H2O2 treatment. We also observed that Lcn2 down-regulated the proapoptotic protein Bax, decreased the levels of cellular ROS, and up-regulated the expression of superoxide dismutases (SOD1 and SOD2). In conclusion, Lcn2 significantly inhibits HPASMC apoptosis induced by oxidative stress via decreased intracellular ROS and elevated SODs. Up-regulation of Lcn2 in a rat PH model and CHD-PH patients may be involved in the pathological process of PH. 相似文献
992.
《Cytotherapy》2014,16(6):734-749
BackgroundClinically, acute kidney injury (AKI) is a potentially devastating condition for which no specific therapy improves efficacy of the repair process. Bone marrow mesenchymal stromal cells (BM-MSCs) are proven to be beneficial for the renal repair process after AKI in different experimental rodent models, but their efficacy in large animals and humans remains unknown. This study aims to assess the effect of autologous rhesus Macaque mulatta monkey BM-MSC transplantation in cisplatin-induced AKI.MethodsWe chose a model of AKI induced by intravenous administration of 5 mg/kg cisplatin. BM-MSCs were transplanted through intra-arterial injection. The animals were followed for survival, biochemistry analysis and pathology.ResultsTransplantation of 5 × 106 cells/kg ameliorated renal function during the first week, as shown by significantly lower serum creatinine and urea values and higher urine creatinine and urea clearance without hyponatremia, hyperkalemia, proteinuria and polyuria up to 84 d compared with the vehicle and control groups. The superparamagnetic iron oxide nanoparticle-labeled cells were found in both the glomeruli and tubules. BM-MSCs markedly accelerated Foxp3+ T-regulatory cells in response to cisplatin-induced damage, as revealed by higher numbers of Foxp3+ cells within the tubuli of these monkeys compared with cisplatin-treated monkeys in the control and vehicle groups.ConclusionsThese data demonstrate that BM-MSCs in this unique large-animal model of cisplatin-induced AKI exhibited recovery and protective properties. 相似文献
993.
Kohei Hasegawa Yusuke Tsugawa Chu-Lin Tsai David FM Brown Carlos A Camargo Jr 《Respiratory research》2014,15(1):40
Background
Little is known about patients who frequently visit the emergency department (ED) for acute exacerbation of chronic obstructive pulmonary disease (AECOPD). We aimed to quantify the proportion and characteristics of patients with frequent ED visits for AECOPD and associated healthcare utilization.Methods
We conducted a retrospective cohort study of adults aged ≥40 years with at least one ED visit for AECOPD between 2010 and 2011, derived from population-based all-payer data of State ED and Inpatient Databases for two large and diverse states: California and Florida. Outcome measures were frequency of ED visits for AECOPD, 30-day ED revisits, subsequent hospitalizations, near-fatal events (AECOPD involving mechanical ventilation), and charges for both ED and inpatient services (available only for Florida) during the year after the first ED visit.Results
The analytic cohort comprised 98,280 unique patients with 154,736 ED visits for AECOPD. During the 1-year period, 29.4% (95% CI, 29.1%-29.7%) of the patients had two or more (frequent) visits, accounting for 55.2% (95% CI, 54.9%-55.4%) of all ED visits for AECOPD. In the multivariable model, significant predictors of frequent ED visits were age 55–74 years (vs. 40–54 years), male sex, non-Hispanic white or black race, Medicaid insurance (vs. private), and lower median household income (all P < 0.001). At the visit-level, 12.3% of ED visits for AECOPD were 30-day revisit events (95% CI, 12.1%-12.4%). Additionally, 62.8% of ED visits for AECOPD (95% CI, 62.6%-63.0%) resulted in a hospitalization; patients with frequent ED visits comprised 55.5% (95% CI, 55.2%-55.8%) of all hospitalizations. Furthermore, 7.3% (95% CI, 7.3%-7.5%) of ED visits for AECOPD led to a near-fatal event; patients with frequent ED visits accounted for 64.4% (95% CI, 63.5%-65.3%) of all near-fatal events. Total charges for AECOPD were $1.94 billion (95% CI, $1.90-1.97 billion) in Florida; patients with frequent ED visits accounted for $1.07 billion (95% CI, $1.04-1.09 billion).Conclusions
In this large cohort study, we found that 29% had frequent ED visits for AECOPD and that lower socioeconomic status was significantly associated with a higher frequency of ED visits. Individuals with frequent ED visits for AECOPD accounted for a substantial amount of healthcare utilization and financial burden. 相似文献994.
Martha Monta?o Raul H Sansores Carina Becerril Jose Cisneros Georgina González-Avila Bettina Sommer Leticia Ochoa Iliana Herrera Alejandra Ramírez-Venegas Carlos Ramos 《Respiratory research》2014,15(1):74
Background
Matrix metalloproteinases (MMPs) and C-reactive protein (CRP) are involved in chronic obstructive pulmonary disease (COPD) pathogenesis. The aim of the present work was to determine plasma concentrations of MMPs and CRP in COPD associated to biomass combustion exposure (BE) and tobacco smoking (TS).Methods
Pulmonary function tests, plasma levels of MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP were measured in COPD associated to BE (n = 40) and TS (n =40) patients, and healthy non-smoking (NS) healthy women (controls, n = 40).Results
Plasma levels of MMP-1, MMP-7, MMP-9, and MMP-9/TIMP-1 and CRP were higher in BE and TS than in the NS healthy women (p <0.01). An inverse correlation between MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP plasma concentrations and FEV1 was observed.Conclusions
Increase of MMPs and CRP plasma concentrations in BE suggests a systemic inflammatory phenomenon similar to that observed in COPD associated to tobacco smoking, which may also play a role in COPD pathogenesis. 相似文献995.
Keishi Oda Hiroshi Ishimoto Kazuhiro Yatera Keisuke Naito Takaaki Ogoshi Kei Yamasaki Tomotoshi Imanaga Toru Tsuda Hiroyuki Nakao Toshinori Kawanami Hiroshi Mukae 《Respiratory research》2014,15(1):10
Background
The 2011 idiopathic pulmonary fibrosis (IPF) guidelines are based on the diagnosis of IPF using only high-resolution computed tomography (HRCT). However, few studies have thus far reviewed the usefulness of the HRCT scoring system based on the grading scale provided in the guidelines. We retrospectively studied 98 patients with respect to assess the prognostic value of changes in HRCT findings using a new HRCT scoring system based on the grading scale published in the guidelines.Methods
Consecutive patients with IPF who were diagnosed using HRCT alone between January 2008 and January 2012 were evaluated. HRCT examinations and pulmonary function tests were performed at six-month intervals for the first year after diagnosis. The HRCT findings were evaluated using the new HRCT scoring system (HRCT fibrosis score) over time. The findings and survival rates were analyzed using a Kaplan-Meier analysis.Results
The HRCT fibrosis scores at six and 12 months after diagnosis were significantly increased compared to those observed at the initial diagnosis (p < 0.001). The patients with an elevated HRCT fibrosis score at six months based on a receiver operating characteristic (ROC) curves analysis had a poor prognosis (log-rank, hazard ratio [HR] 2.435, 95% CI 1.196-4.962; p = 0.0142). Furthermore, among the patients without marked changes in %FVC, those with an elevated score above the cut-off value had a poor prognosis (HR 2.192, 95% CI 1.003-4.791; p = 0.0491).Conclusions
Our data demonstrate that the HRCT scoring system based on the grading scale is useful for predicting the clinical outcomes of IPF and identifying patients with an adverse prognosis when used in combination with spirometry. 相似文献996.
Radiation pressure on a biconcave human Red Blood Cell and the resulting deformation in a pair of parallel optical traps 下载免费PDF全文
Guan‐Bo Liao Yin‐Quan Chen Paul B. Bareil Yunlong Sheng Arthur Chiou Ming‐Shien Chang 《Journal of biophotonics》2014,7(10):782-787
We calculated the three‐dimensional optical stress distribution and the resulting deformation on a biconcave human red blood cell (RBC) in a pair of parallel optical trap. We assumed a Gaussian intensity distribution with a spherical wavefront for each trapping beam and calculated the optical stress from the momentum transfer associated with the reflection and refraction of the incident photons at each interface. The RBC was modelled as a biconcave thin elastic membrane with uniform elasticity and a uniform thickness of 0.25 μm. The resulting cell deformation was determined from the optical stress distribution by finite element software, Comsol Structure Mechanics Module, with Young's modulus (E) as a fitting parameter in order to fit the theoretical results for cell elongation to our experimental data. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
997.
Masako Y Endo Chizuko Fujihara Chinami Yamazaki Hideaki Kashima Kouhei Eguchi Akira Miura Yoshiyuki Fukuoka Yoshiyuki Fukuba 《Journal of physiological anthropology》2014,33(1):11
Background
Recently, it was reported in healthy young subjects that fructose containing drinks increased blood pressure acutely, without any apparent change in total vascular conductance (TVC). However, because it is well known that the splanchnic vasculature is dilated by oral fructose ingestion, it is assumed to be the concomitant vasoconstriction in other peripheral region(s) that is responsible for this finding. Thus, the purpose of this study was to determine the acute response of regional VC to oral fructose ingestion in young healthy humans.Results
In 12 healthy young subjects, mean arterial blood pressure (MAP), heart rate, cardiac output, and blood flow (BF) in the superior mesenteric (SMA), brachial (BA), and popliteal (PA) arteries, in addition to forearm skin BF, were measured continuously for 2 h after ingestion of 400 ml fructose solution (containing 50 g fructose). Regional VC was calculated as BF/MAP. MAP increased for 120 min after fructose ingestion without any change in TVC. While VC in the SMA was elevated after ingestion, VC in BA and PA and forearm skin decreased.Conclusions
While TVC was apparently unchanged during the 2 h after fructose ingestion, there were coincident changes in regional VCs in the peripheral circulation, but no net change in TVC. 相似文献998.
目的:探究姜黄素改善慢性低O2高CO2大鼠肺动脉高压肺血管重塑作用途径的研究。方法:建立慢低O2高CO2肺血管重塑模型,以24只雄性大鼠为受试对象,随机分为四组(n=6):I组(常氧空白对照组),Ⅱ(低O2高CO2模型组),Ⅲ组(色甘酸钠对照组),Ⅳ组(姜黄素实验组)。将后3组动物放入常压低O2高CO2舱中,吸入O2浓度8%~11%,CO2浓度3%~5%,每天8h,每周6d,连续4周,Ⅲ组给予色甘酸钠以20mg/kg体重腹注射处理,Ⅳ组给予姜黄素混悬液按150mg/kg体重灌胃处理。光镜下、透射电镜下观察肺动脉血管壁及其周围大细胞超微结构形态学改变,甲苯胺蓝染色法和免疫组织化学法对肺动脉周围的肥大细胞及其脱颗粒状态进行性定量测定。结果:①电镜下,Ⅱ组肺细小动脉中膜平滑肌增生,外膜胶原纤维密集,内弹力板扭曲,内皮细胞起,血管外肥大细胞内颗粒减少,胞膜不完整;光镜下,Ⅱ组相比1组肺细小动脉管腔/管总面积(WA/TA)明显升(P〈0.05)、管腔/管总面积(EA/TA)明显降低(P〈0.05),甲苯胺蓝染色肥大细胞细胞数(NMC)、肥大细胞脱颗率(DR)及免疫组化检测类胰蛋白酶阳性细胞数(TBS)高于I组(P〈0.05);②干预后,电镜下,Ⅲ组、Ⅳ组血管结基本正常,平滑肌增生及胶原增生较Ⅱ组轻,肥大细胞膜完整;光镜下,两干预组相比Ⅱ组WA/TA明显降低(P〈0.05)、ET/TA明显升高(P〈0.05),甲苯胺蓝染色NMC、DR、TBS阳性细胞数分别低于Ⅱ组(P〈0.05)。结论:姜素可通过Mc途径抑制慢性低O2高CO2导致的大鼠肺血管重塑改变。 相似文献
999.
目的:研究低氧暴露对大鼠脑和肺微动脉内皮功能的影响以及埃他卡林(Ipt)对以上微动脉的扩张作用特征。方法:将雄性SD大鼠随机分为2组,常压常氧组(control)和低氧暴露组(hypoxic),后者置于常压低氧暴露舱内(O27.8%)8 h。分离大鼠管径为(204±5)μm的脑基底动脉、肺微动脉组织,利用DMT微血管张力测定仪在6nmol/L内皮素-1(ET-1)致血管预收缩条件下,利用乙酰胆碱(ACh)考察微动脉内皮功能及观察不同浓度Ipt对脑和肺微动脉张力变化的影响。结果:与常压常氧组对比,10-5 mol/L乙酰胆碱(ACh)对低氧暴露脑肺微动脉扩张率显著降低(P0.05);新型ATP敏感性钾通道开放剂Ipt在(10-11~10-3)mol/L对低氧暴露肺微动脉呈剂量依赖性扩张作用,明显强于对常压常氧组(P0.01),在(10-11~10-3)mol/L对低氧暴露脑微动脉呈剂量依赖性扩张作用,但与常压常氧组相比无显著差异。结论:低氧暴露可导致脑基底动脉和肺微动脉内皮功能受损,Ipt具有选择性增强扩张低氧暴露肺微动脉的作用,但不影响以上条件低氧暴露后脑基底动脉的扩张作用,提示该药可应用于改善低氧暴露所致的肺微血管收缩,为Ipt发展为新型治疗肺动脉高压的药物提供理论基础。 相似文献
1000.
目的评价肺水相关指数对重症烧伤并发急性呼吸窘迫综合征(ARDS)患者严重程度、预后判断的价值。方法对31例重症烧伤并发ARDS患者,除记录一般临床资料及主要合并症外,均利用脉搏指示剂连续心输出量(PiCCO)监测仪监测,并记录置入PiCCO导管时的急性生理和慢性健康状况(APACHE)Ⅱ评分,置管后0、24、48、72h氧合指数,肺血管通透性指数(PVPI)和血管外肺水指数(EVLWI)值。根据28天预后分为存活组和死亡组,分析两组各指数之间的差异及其对预后的评估能力。结果纳入研究的31例患者中,28天内死亡21例(67.7%),吸入性损伤、脓毒血症是主要合并症及影响预后的主要因素。存活组患者置管后72h氧合指数高于死亡组,差异有统计学意义(P0.05);存活组患者置管后48、72hPVPI低于死亡组,差异有统计学意义(P0.05);存活组患者置管后24、48、72hEVLWI低于死亡组,差异有统计学意义(P0.05);且随着置管时间延长,氧合指数、PVPI、EVLWI均对预后评价准确性增加,置管后72h的氧合指数、PVPI、EVLWI值对预后的评价最佳,3个指数对预后评估价值差异无统计学意义(P0.05)。结论运用PiCCO监测仪对肺水相关指数连续监测对重症烧伤并发ARDS患者严重程度、预后评价具有重要临床意义。 相似文献