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C Antoniades D Tousoulis C Tountas C Tentolouris M Toutouza C Vasiliadou C Tsioufis P Toutouzas C Stefanadis 《Diabetic medicine》2004,21(6):552-558
AIMS: Type 2 diabetes mellitus (DM) and coronary artery disease (CAD) are both associated with endothelial dysfunction and elevated oxidative and inflammatory state. We examined the effect of vitamin C on endothelial function and levels of soluble vascular cell adhesion molecule (sVCAM-1), interleukin-6 (IL-6) and tumour necrosis factor (TNF-alpha), in DM patients with or without CAD and in non-diabetic subjects. METHODS: Thirty-seven patients with DM + CAD, 17 patients with DM without CAD and 21 non-diabetic subjects were divided into groups receiving vitamin C 2 g/day or no anti-oxidant for 4 weeks. Forearm blood flow was determined using venous occlusion gauge-strain plethysmography. Forearm vasodilatory response to reactive hyperemia was considered as index of endothelium-dependent dilation. RESULTS: Baseline levels of IL-6 and TNF-alpha were significantly higher in patients with DM + CAD compared with patients with DM (P < 0.01) or non-diabetic subjects (P < 0.01). IL-6 and TNF-alpha levels were also higher in DM compared with non-diabetic subjects (P < 0.05). sVCAM-1 levels were lower in non-diabetic controls compared with DM + CAD (P < 0.05) or DM (P < 0.05). Reactive hyperaemia was higher in non-diabetic controls compared with DM + CAD (P < 0.001) or DM (P < 0.001). Vitamin C significantly increased reactive hyperaemia only in the DM + CAD group, while it had no effect on serum levels of sVCAM-1, TNF-alpha and IL-6 in any of the groups. CONCLUSIONS: Type 2 diabetes mellitus is associated with impaired endothelial function and increased levels of TNF-alpha, IL-6 and sVCAM-1, especially in patients with DM and CAD. Vitamin C significantly increased forearm vasodilatory response to reactive hyperaemia only in patients with combined DM and CAD. 相似文献
44.
Inflammation and the Aging Process: Devil or Angel 总被引:1,自引:0,他引:1
Inflammation is often viewed as a pathologic mechanism leading to tissue damage and interference with function, such as the process of chronic tissue scarring or fibrosis. However, it is important to note that inflammation is a crucial component of normal tissue repair as well as being fundamental to the body's defense against infection. Considering inflammation as a "causative agent in aging" belies the underlying mechanisms whereby the acute inflammatory response is necessary for survival, and efforts to reduce and control the inflammatory response leave the host susceptible to infectious agents and improper healing. Chronic inflammation inevitably has initiating mechanisms that include immune, autoimmune, and metabolic pathways, leading to the activation and presence of the host-protective response. It is more appropriate to target the underlying initiating conditions than the inflammatory process that ensues and treat the basic mechanisms of disease rather than interfere in a very important protective mechanism of the host. 相似文献
45.
Comparison of the effect of intravenous ketoprofen, ketorolac and diclofenac on platelet function in volunteers 总被引:1,自引:0,他引:1
Background : Nonsteroidal anti–inflammatory drugs (NSAIDs) inhibit prostaglandin synthesis which may result in impaired platelet function. Because NSAIDs have different abilities to inhibit cyclo–oxygenases we compared the effect of intravenous ketoprofen, ketorolac and diclofenac on platelet function in volunteers. Methods : Ten healthy male volunteers were given ketoprofen 1.4 mg kg-1, ketorolac 0.4 mg kg-1 and diclofenac 1.1 mg kg-1 in saline i.v. on three different occasions, at more than one–week intervals, in a randomized double–blind crossover study. Platelet function was evaluated before (sample 0), 2 (sample 2) and 24 h (sample 3) after the beginning of the infusion. Results : Two of the volunteers had no secondary platelet aggregation in their aggregation curves before the experiment (sample 0, studied three times) and their results were excluded from the final analysis. Diclofenac inhibited adrenaline (0.9 μg–ml-1) induced platelet aggregation less (median maximal aggregation 22.5%) than ketoprofen (18.3%) and ketorolac (15.7%) (P<0.05) in sample 2. In the ketorolac group in sample 3 an impairment of adrenaline (0.9 ng ml-1) induced platelet aggregation was still seen (26.7%) (P<0.05) but not in the other groups. Diclofenac did not affect adenosine diphosphate (ADP) induced platelet aggregation. However, ketorolac caused an impairment in ADP (3 μM and 6 μM) induced platelet aggregation and ketoprofen in ADP (6 μM) induced platelet aggregation in sample 2. Bleeding time was prolonged (P<0.05) after ketoprofen and ketorolac (sample 2) but not after diclofenac. Platelet retention on glass beads was unaffected by the tested drugs. Conclusion : Ketoprofen, ketorolac and diclofenac caused a reversible platelet dysfunction. Diclofenac had the mildest effect, while platelet dysfunction was still seen 24 h after the beginning of ketorolac. 相似文献
46.
R. D. Myers F. J. Lopez-Valpuesta F. J. Minano M. H. Wooten V. S. Barwick S. D. Wolpe 《Journal of neuroscience research》1994,39(1):31-37
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc. 相似文献
47.
肺部炎性假瘤20例,其中1例肺癌误诊为炎性假瘤,2例肺炎性假瘤与肺癌并存。炎性假瘤病灶多为单发,分布在两侧不同肺野内,可分为圆结节、不规则形、弥漫浸润及肺不张型。重点讨论本病诊断及外科治疗体会。 相似文献
48.
目的:探讨肺炎性假瘤的病理类型和临床特点;方法:根据1988年(HUNPATHOL)MATSUBRA等分型方法,对50例肺炎性假瘤进行临床病理分析;结果:机化肺炎型23例,纤维组织细胞型16例,淋巴浆细胞型11例;结论:肺炎性假瘤其性质均为良性,男性多于女性,共同的病理特点是纤维母细胞增生、血管增生,组织细胞、淋巴细胞、浆细胞浸润,肺泡细胞增殖。 相似文献
49.
Chemokine receptor CCR6 as a prognostic factor after hepatic resection for hepatocellular carcinoma 总被引:3,自引:0,他引:3
HIROKI UCHIDA YUKIO IWASHITA ATSUSHI SASAKI KOHEI SHIBATA TOSHIFUMI MATSUMOTO MASAYUKI OHTA SEIGO KITANO 《Journal of gastroenterology and hepatology》2006,21(1):161-168
Background and Aims: Chemokines and their receptors have recently been shown to have major roles in cancer metastasis. The aim of this study was to determine whether the interaction between chemokine receptor 6 (CCR6) and its ligand, macrophage inflammatory protein‐3 alpha (MIP‐3α), correlates with metastasis of hepatocellular carcinoma (HCC). Methods: To observe the reaction of CCR6 expressed cancer cells to MIP‐3α stimulation, chemotactic and actin polymerization assays for both CCR6 high cells (HepG2) and CCR6 low cells (MCF‐7) were performed. CCR6 mRNA levels in tumor specimens from 30 HCC patients were quantified by real‐time polymerase chain reaction. Patients were classified into two groups, high (≥ 20 copies; n = 10) CCR6 and low (<20 copies; n = 20) CCR6 on the basis of CCR6 expression, and the groups were compared with respect to clinicopathological features. Results: When HepG2 cells (CCR6 high) were stimulated with MIP‐3α, they migrated in a dose‐dependent manner, and formation of pseudopodia was observed. These phenomena were not observed in the CCR6 low cells. The incidence of intrahepatic metastasis was higher in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Disease‐free survival was significantly poorer in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Conclusions: It was indicated that CCR6 might be associated with intrahepatic metastasis of HCC and might be able to become one of the prognostic factor after hepatic resection for HCC. 相似文献
50.
目的 探讨膀胱前间隙炎性假瘤的临床病理特征及发病因素,以提高对本病的认识。方法 复习3例膀胱前间隙炎性假瘤的临床特征、组织病理学、免疫表型及相关文献。结果 3例患者均为女性,均为输卵管结扎术后1~2年发现膀胱前间隙炎性假瘤,CT及B超提示膀胱前壁肿块,但膀胱黏膜光滑。术中发现肿块位于膀胱前间隙并累及膀胱前壁。病理检查:眼观为灰白色质韧的结节状肿块,镜下见炎性假瘤的病理特征及不同程度炎症背景,有组织疏松区、黏液样区、部分区域梭形细胞和纤维母细胞排列杂乱,细胞较大,光镜检查时易误诊为肉瘤,但缺乏核异型。3例均成功行肿块连同部分膀胱壁切除术,随访3~5年无复发。结论 膀胱前间隙炎性假瘤形态上需与软组织肉瘤、结节性筋膜炎、术后梭形细胞结节、间质性膀胱炎等疾病相鉴别,既往输卵管结扎术和感染可能是其重要的致病因素。 相似文献