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31.
Christos Karathanos Maria Exarchou Aspasia Tsezou Despina Kyriakou Cees Wittens Athanasios Giannoukas 《Thrombosis research》2013
Introduction
Superficial vein thrombosis (SVT) is a common and controversial clinical entity. Recent studies have demonstrated that SVT should be seen as a venous thromboembolism (VTE). The objective of this study was to investigate the prevalence of thrombophilia defects and to estimate the role of age, sex and body mass index (BMI) in patients with varicose veins (VVs) and SVT.Materials and Methods
A total of 230 patients with VVs, 128 with, and 102 without SVT underwent thrombophilia testing included factor V Leiden, prothrombin G20210A, methylenetetrahydrofolate reductase and plasminogen activator inhibitor- 1 mutations, protein C, protein S (PS), anti-thrombin III and plasminogen deficiencies and levels of A2 antiplasmin, activate protein C resistance and lupus anticoagulant. According to Clinical- Etiology- Anatomy- Pathophysiology (CEAP) classification patients were categorized in two subgroups: moderate disease (C2,3) and severe disease (C4,5,6). Age and body mass index were also assessed.Results
The prevalence of thrombophilia defects was significantly higher in patients with moderate disease and SVT (p = 0.002). In the C2,3 group, SVT was associated with PS deficiency (p = 0.018), obesity (p < 0.001), male gender (p = 0.047) and age (p < 0.001). There were no significant differences in patients with severe disease.Conclusions
Age, male sex, obesity and PS deficiency are factors associated with SVT development among patients with VVs having moderate disease (C2,3). 相似文献32.
《Neurological research》2013,35(10):1109-1114
Abstract Objective: To study the effect of hippocampal bone marrow stromal cells (GFP-BMSCs) transplantation on spatial memory and DeltaNp73 expression in APP/PS1 transgenic mice. Methods: Twelve APP/PS1 transgenic mice randomly received either 10 μl GFP-BMSCs suspension in medium (GFP-BMSCs transplantation group) or 10 μl complete medium (sham-operated group). Learning and memory function of mice in both groups were observed and tested in Morris water maze experiment at 2 weeks after surgery. Senile plaques and DeltaNp73 protein in hippocampuses were determined by immunohistochemistry and western blot at 3 weeks after surgery, respectively. Results: APP/PS1 mice treated with BMSCs performed significantly better on the water maze test than those in sham-operated group (P<0·05). Immunohistochemistry showed that GFP-BMSCs distributed uniformly and the number of Alzheimer’s senile plaques reduced after transplantation. Western blot showed that quantified DeltaNp73 protein expression was significantly higher in BMSCs transplantation group when compared with sham-operated group (P<0·01). Conclusions: Our results suggest that BMSCs transplatation could retard Alzheimer’s disease (AD) like pathology and upregulate DeltaNp73 expression in hippocampuses of APP/PS1 transgenic mice. GFP-BMSCs transplantation will be a potential treatment for AD. 相似文献
33.
Zierhut ML Gardner JC Spilker ME Sharp JT Vicini P 《Annals of biomedical engineering》2007,35(5):781-795
In recent years, development of rheumatoid arthritis (RA) drug therapy has been more directly targeted to counteract specific
mechanisms of inflammation, and it is now believed that early aggressive treatment with disease modifying drugs is important
to inhibit future structural joint damage. The development of these new treatments has increased the need for methodologies
to assess disease activity in RA and monitor the effectiveness of drug therapy. Unlike X-ray, which shows only structural
bone damage, magnetic resonance imaging (MRI) can depict soft tissue damage and synovitis, the primary pathology of RA. Recent
studies have also indicated that MRI is sensitive to pathophysiologic changes that may predate radiographic erosions and may
predict future joint damage. In this study, we have developed a computer automated analysis technique for MR wrist images
that provides an objective measure of RA synovitis. This method applies a two-compartment pharmacokinetic model to every voxel
of a dynamic contrast-enhanced MRI (DCE-MRI) dataset and outputs resulting parametric images. The aim of this technique is
to not only objectively quantify the severity of rheumatoid synovitis, but to also locally determine where areas of serious
disease activity are situated through kinetic modeling of blood-tissue exchange. Preliminary results show good correlation
to early enhancement rate, which has previously been shown to be a useful clinical marker of RA activity. However, the use
of tracer kinetic modeling methods potentially provides more specific information regarding underlying RA physiology. This
approach could provide a useful new tool in RA patient management and could substantially improve RA therapeutic studies by
calculating objective biomarkers of the disease state. 相似文献
34.
Hammond LE Albright CD He L Rusyn I Watkins SM Doughman SD Lemasters JJ Coleman RA 《Experimental and molecular pathology》2007,82(2):210-219
The absence of mouse mitochondrial glycerol-3-phosphate acyltransferase-1 (Gpat1-/-) increases the amount of arachidonate in liver phospholipids and increases beta-hydroxybutyrate and acyl-carnitines, suggesting an elevated rate of liver fatty acid oxidation. We asked whether these alterations might increase reactive oxygen species (ROS), apoptosis, or hepatocyte proliferation. Compared to wildtype controls, liver mitochondria from Gpat1-/- mice showed a 20% increase in the rate of ROS production and a markedly increased sensitivity to the induction of the mitochondrial permeability transition. Mitochondrial phosphatidylethanolamine and phosphatidylcholine from Gpat1-/- liver contained 21% and 67% more arachidonate, respectively, than wildtype controls, and higher amounts of 4-hydroxynonenal, a product of arachidonate peroxidation. Oxidative stress was associated with an increase in apoptosis, and with 3-fold and 15-fold higher TUNEL positive cells in liver from young and old Gpat1-/- mice, respectively, compared to age-matched controls. Compared to controls, bromodeoxyuridine labeling was 50% and 7-fold higher in livers from young and old Gpat1-/- mice, respectively, but fewer glutathione-S-transferase positive cells were present. Thus, Gpat1-/- liver exhibits increased oxidative stress and sensitivity of the mitochondrial permeability transition pore, and a balanced increase in apoptosis and proliferation. 相似文献
35.
Ying Wan John M. Hickey Christopher Bird Katey Witham Paul Fahey Angus Forster Sangeeta B. Joshi David B. Volkin 《Journal of pharmaceutical sciences》2018,107(6):1540-1551
The worldwide switch to inactivated polio vaccines (IPVs) is a key component of the overall strategy to achieve and maintain global polio eradication. To this end, new IPV vaccine delivery systems may enhance patient convenience and compliance. In this work, we examine Nanopatch? (a solid, polymer microprojection array) which offers potential advantages over standard needle/syringe administration including intradermal delivery and reduced antigen doses. Using trivalent IPV (tIPV) and a purpose-built evaporative dry-down system, candidate tIPV formulations were developed to stabilize tIPV during the drying process and on storage. Identifying conditions to minimize tIPV potency losses during rehydration and potency testing was a critical first step. Various classes and types of pharmaceutical excipients (~50 total) were then evaluated to mitigate potency losses (measured through D-antigen ELISAs for IPV1, IPV2, and IPV3) during drying and storage. Various concentrations and combinations of stabilizing additives were optimized in terms of tIPV potency retention, and 2 candidate tIPV formulations containing cyclodextrin and a reducing agent (e.g., glutathione), maintained ≥80% D-antigen potency during drying and subsequent storage for 4 weeks at 4°C, and ≥60% potency for 3 weeks at room temperature with the majority of losses occurring within the first day of storage. 相似文献
36.
Ping-ping LI ;Wei-ping WANG ;Zhi-hui LIU ;Shao-feng XU ;Wen-wen LU ;Ling WANG ;Xiao-liang WANG 《Acta pharmacologica Sinica》2014,35(7):869-878
Aim: Potassium 2-(1-hydroxypentyl)-benzoate (d/-PHPB) is a new drug candidate for ischemic stroke. The aim of this study was to investigate the effects of dI-PHPB on memory deficits and long-term potentiation (LTP) impairment in animal models of Alzheimer's disease. Methods: The expression of NMDA receptor subunits GluN1 and GluN2B in the hippocampus and cortex of APP/PS1 transgenic mice were detected using Western blot analysis. Memory deficits of the mice were evaluated with the passive avoidance test. LTP impairment was studied in the dentate region of Aβ1-42-injected rats and APP/PS1 transgenic mice. Results: APP/PS1 transgenic mice showed significantly lower levels of GluN1 and p-GluN2B in hippocampus, and chronic administration of dI-PHPB (100 mg·kg-1·d1, po) reversed the downregulation of p-GluN2B, but did not change GluN1 level in the hippocampus. Furthermore, chronic administration of d/-PHPB reversed the memory deficits in APP/PS1 transgenic mice. In the dentate region of normal rats, injection of dI-PHPB (100 μmol/L, icv) did not change the basal synaptic transmission, but significantly enhanced the high-frequency stimulation (HFS)-induced LTP, which was completely prevented by pre-injection of APV (150 μmol/L, icv). Chronic administration of dI-PHPB (100 mg·kg-1·d-1, po) reversed LTP impairment in Aβ1-42 -injected normal rats and APP/PS1 transgenic mice. Conclusion: Chronic administration of d/-PHPB improves learning and memory and promotes LTP in the animal models of Alzheimer's disease, possibly via increasing p-GluN2B expression in the hippocampus. 相似文献
37.
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39.
目的研究五味子醇甲(SCH)对APP/PS1双转基因痴呆小鼠行为学和NF-κB p65的影响。方法将35只APP/PS1双转基因痴呆小鼠随机分为模型(APP/PS1)组、五味子醇甲(SCH+APP/PS1)组;另以同背景同月龄的C 57 BL/6 J阴性小鼠为空白(WT)组。SCH+APP/PS1组给予SCH悬浊液灌胃(2.6 mg·kg^-1·d^-1),模型组和空白组给予等量蒸馏水灌胃。各组灌胃30 d进行Mirror水迷宫空间探索试验后取材。HE染色法观察皮层及海马CA1区神经细胞的形态结构。运用DCFH-DA法检测脑组织活性氧(ROS)含量。Western印迹检测法检验磷酸化核转录因子(NF-κB p65,pp65)的表达。结果与APP/PS 1组相比,APP/PS 1+SCH组有效区停留距离及时间明显延长,差异有统计学意义(P<0.05,P<0.01);APP/PS 1+SCH组穿越有效区次数和平台区停留距离增加,均差异有统计学意义(P<0.01)。APP/PS 1+SCH组HE染色观察皮层有部分神经细胞萎缩、减少,较APP/PS1组明显好转,海马细胞排列整齐度尚可、较均匀。与APP/PS1组相比,APP/PS1+SCH组能降低ROS含量,差异有统计学意义(P<0.05)。APP/PS 1+SCH组皮层及海马pp65蛋白相对表达量下调(P<0.05,P<0.01)。结论SCH可能通过降低ROS含量和抑制pp65保护脑组织形态结构和提高APP/PS1鼠空间探索记忆能力。 相似文献
40.
目的研究特异性激动APP/PS1转基因小鼠脑组织中α7神经型尼古丁受体(α7 nAChR)水平后对海马组织DYN-Ⅰ蛋白的影响;探讨α7 nAChR在阿尔茨海默病(Alzheimer disease,AD)发病机制中的神经保护作用机制。方法实验动物分为对照组(Control)、野生加PNU282987组(WP)、APP/PS1转基因组(APP/PS1)和APP/PS1加PNU282987组(AP)各8只,WP和AP组给予α7 nAChRs特异性激动剂PNU-282987,另两组给予生理盐水,给药方式为小鼠24 w龄时1 mg/kg腹腔注射PNU-282987,连续5 d。采用Real-time PCR法和蛋白免疫印迹(Western Blot)法分别测定小鼠海马组织中发动蛋白Ⅰ(DYN-Ⅰ)mRNA和蛋白表达水平的变化。结果与control组相比,APP/PS1组海马组织中发动蛋白Ⅰ(DYN-Ⅰ)mRNA和蛋白水平下降(P0.05,P0.01);而特异性激动α7 nAChR水平后,与对照组相比WP组中发动蛋白Ⅰ(DYN-Ⅰ)mRNA和蛋白水平升高(P0.05,P0.01);与APP/PS1组相比AP组小鼠大脑海马组织中发动蛋白Ⅰ(DYN-Ⅰ)mRNA和蛋白水平明显升高(P0.01,P0.01)。结论特异性激动APP/PS1转基因小鼠海马组织中α7 nAChR水平能够使网格蛋白内吞调节蛋白DYN-Ⅰ表达升高。这可能提示了α7 nAChR对突触有一定的保护作用,进一步说明α7 nAChR在阿尔茨海默病的发病中起着重要作用。 相似文献