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71.
Bogdanova OV Kot LI Lavrova KV Bogdanov VB Sloan EK Beregova TV Ostapchenko LI 《World journal of biological chemistry》2010,1(11):338-347
AIM: To investigate the role of protein tyrosine phosphorylation in gastric wound formation and repair following ulceration.METHODS: Gastric lesions were induced in rats using restraint cold stress. To investigate the effect of oxidative and nitrosative cell stress on tyrosine phosphorylation during wound repair, total activity of protein tyrosine kinase (PTK), protein tyrosine phosphatase (PTP), antioxidant enzymes, nitric oxide synthase (NOS), 2’,5’-oligoadenylate synthetase, hydroxyl radical and zinc levels were assayed in parallel.RESULTS: Ulcer provocation induced an immediate decrease in tyrosine kinase (40% in plasma membranes and 56% in cytosol, P < 0.05) and phosphatase activity (threefold in plasma membranes and 3.3-fold in cytosol), followed by 2.3-2.4-fold decrease (P < 0.05) in protein phosphotyrosine content in the gastric mucosa. Ulceration induced no immediate change in superoxide dismutase (SOD) activity, 30% increase (P < 0.05) in catalase activity, 2.3-fold inhibition (P < 0.05) of glutathione peroxidase, 3.3-fold increase (P < 0.05) in hydroxyl radical content, and 2.3-fold decrease (P < 0.05) in zinc level in gastric mucosa. NOS activity was three times higher in gastric mucosa cells after cold stress. Following ulceration, PTK activity increased in plasma membranes and reached a maximum on day 4 after stress (twofold increase, P < 0.05), but remained inhibited (1.6-3-fold decrease on days 3, 4 and 5, P < 0.05) in the cytosol. Tyrosine phosphatases remained inhibited both in membranes and cytosol (1.5-2.4-fold, P < 0.05). NOS activity remained increased on days 1, 2 and 3 (3.8-, 2.6-, 2.2-fold, respectively, P < 0.05). Activity of SOD increased 1.6 times (P < 0.05) days 4 and 5 after stress. Catalase activity normalized after day 2. Glutathione peroxidase activity and zinc level decreased (3.3- and 2-fold, respectively, P < 0.05) on the last day. Activity of 2’,5’-oligoadenylate synthethase increased 2.8-fold (P < 0.05) at the beginning, and 1.6-2.3-fold (P < 0.05) during ulcer recuperation, and normalized on day 5, consistent with slowing of inflammation processes.CONCLUSION: These studies show diverse changes in total tyrosine kinase activity in gastric mucosa during the recovery process. Oxidative and nitrosative stress during lesion formation might lead to the observed reduction in tyrosine phosphorylation during ulceration. 相似文献
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73.
目的观察不同造模方法致糖尿病大鼠慢性皮肤溃疡创面形态及愈合时间的影响。方法 50只SD大鼠随机分为5组:皮肤缺损组(QS组:剪皮),糖尿病组(DM组:STZ+剪皮),糖尿病加金黄色葡萄球菌组(DMJJ组:STZ+剪皮+金葡菌),糖尿病加激素组(DMJS组:STZ+剪皮+激素注射),糖尿病加激素加异物组(DMYW组:STZ+剪皮+激素注射+异物埋置)。糖尿病模型稳定后每周测量血糖1次,每日称量体重、观察疮面情况、测量创面面积。12 d后处死,石蜡包埋肉芽组织观察其组织病理形态。结果 DMJJ组前5d愈合速度快于其余组(P0.01);DMYW组的愈合时间延长,DMYW组愈合率显著偏低,与其余组比较有统计学意义(P0.01)。造模12 d其余组愈合率无统计学差异,DMYW组愈合率显著低于其余组(P0.01)。结论注射激素大鼠表现出中医"阴证"证型特点,糖尿病加激素注射加异物埋置复合因素造模法能使大鼠创面表现出与临床相似的"阴证"证型特点。 相似文献
74.
目的观察绍兴市人民医院血管外科慢性下肢静脉曲张性溃疡(CLU)患者的病原菌分布以及耐药特点,为临床合理用药提供依据。方法对该院血管外科2012年1月至2013年12月的CLU患者,其溃疡面渗出物培养出的病原菌及耐药性进行回顾性分析。结果病原菌分布较广泛,以铜绿假单胞菌和金黄色葡萄球菌为主。金黄色葡萄球菌对青霉素G的耐药率最高,达到97.37%,对红霉素和克林霉素的耐药率分别为60.53%和55.26%,对利奈唑烷和万古霉素全部敏感。铜绿假单胞菌对抗生素的敏感性较好。结论 CLU患者感染的病原菌分布广泛,且易多重感染,临床在采用外科治疗的同时,宜合理使用抗生素,针对不同患者采取个体化、系统化治疗方案,以提高治愈率,降低复发率。 相似文献
75.
《Cytokine》2014,65(2):143-147
Leg ulcers (LUs) represent one of the main causes of morbidity in sickle cell anemia (SCA). This manifestation has been related to hemolysis, infections predisposition and inflammation that leads cytokines secretion. In this context, our study aimed to evaluate Th17 related cytokines (IL-6, IL-17A, IL-22 and IL-23) in serum and peripheral mononuclear cells culture supernatants with and without lymphoproliferative stimulation (anti-human CD3 and anti-human CD28). The cytokines levels were also correlated to clinical, hematological and biochemical parameters in SCA patients with and without LUs history (SCALU and SCAWH) as well as in healthy controls. In SCALU patients, high levels of IL-17A were associated with absence of acute chest syndrome (ACS, p = 0.0328). The other clinical parameters analyzed (osteonecrosis, stroke, priapism, splenectomy and blood transfusions history) were not significantly related with other cytokine levels. In SCALU patients was also observed that IL-17A increased levels were associated with high levels of LDH (p = 0.0130), the same association pattern was found for IL-6 (0.0160) and IL-22 (p = 0.0165) in the SCALU group. Interestingly, we did not find statistical correlations with these parameters in SCAWH group. The other hematological parameters (hemoglobin, leucocyte and reticulocyte count) and indirect bilirrubin did not show any correlation with analyzed cytokines in both groups. So, for the first time, we show that IL-17A present in SCALU patients may exert a preventive role in the ACS development. Furthermore, IL-6, IL-17A and IL-22 accompanied the LDH levels only in SCALU patients suggesting to serve as additional markers of hemolysis or to be related with immunity response against extracellular pathogens. 相似文献
76.
77.
S. Portnoy I. Siev-Ner N. Shabshin 《Computer methods in biomechanics and biomedical engineering》2013,16(11):1009-1019
Transtibial amputation prosthetic-users are at risk of developing deep tissue injury (DTI) while donning their prosthesis for prolonged periods; however, no study addresses the mechanical loading of the residuum during sitting with a prosthesis. We combined MRI-based 3D finite element modelling of a residuum with an injury threshold and a muscle damage law to study risks for DTI in one sitting subject in two postures: 30°-knee-flexion vs. 90°-knee-flexion. We recorded skin-socket pressures, used as model boundary conditions. During the 90°-knee-flexion simulations, major internal muscle injuries were predicted (>1000 mm3). In contrast, the 30°-knee-flexion simulations only produced minor injury ( < 14 mm3). Predicted injury rates at 90°-knee-flexion were over one order of magnitude higher than those at 30°-knee-flexion. We concluded that in this particular subject, prolonged 90°-knee-flexion sitting theoretically endangers muscle viability in the residuum. By expanding the studies to large subject groups, this research approach can support development of guidelines for DTI prevention in prosthetic-users. 相似文献
78.
大鼠脑内5-羟色胺在应激性溃疡形成中的作用 总被引:9,自引:0,他引:9
通过神经化学和神经药理学的方法,在大鼠观察了冷冻加束缚应激性溃疡的形成过程中,脑内5-羟色胺(5-HT)的作用。结果如下:1.在应激过程中,脑内5-HT 及其主要代谢产物5-羟吲哚乙酸(5-HIAA)的含量明显升高,特别是5-HIAA 的含量随着应激时间的延长持续上升,说明5-HT 的代谢加快。2.脑内5-HT 或5-HIAA 含量在应激45min 时与溃疡指数呈明显的负相关,而在应激180min 时则与溃疡指数呈明显的正相关。3.侧脑室注射5-HT或其前体5-羟色氨酸(5-HTP),对应激性溃疡的形成呈双重作用,小剂量时减轻而大剂量时加重溃疡的形成。4.腹腔注射5-HT 合成阻断剂对氯苯丙氨酸(pCPA)可降低大鼠脑内5-HT 和5-HIAA 含量,使应激60min 鼠的溃疡形成加重,而使应激180min 鼠的溃疡形成减轻。以上结果提示,在大鼠的冷冻加束缚应激性溃疡的形成过程中,脑内5-HT 起着一定的作用,它很可能在应激早期减轻而在应激晚期加重溃疡的形成。 相似文献
79.
Hydrogen gas inhalation protects against cutaneous ischaemia/reperfusion injury in a mouse model of pressure ulcer 下载免费PDF全文
Wei Fang Guizhen Wang Luyan Tang Huilin Su Huyan Chen Wanqing Liao Jinhua Xu 《Journal of cellular and molecular medicine》2018,22(9):4243-4252
Pressure ulcer formation depends on various factors among which repetitive ischaemia/reperfusion(I/R) injury plays a vital role. Molecular hydrogen (H2) was reported to have protective effects on I/R injuries of various internal organs. In this study, we investigated the effects of H2 inhalation on pressure ulcer and the underlying mechanisms. H2 inhalation significantly reduced wound area, 8‐oxo‐dG level (oxidative DNA damage) and cell apoptosis rates in skin lesions. H2 remarkably decreased ROS accumulation and enhanced antioxidant enzymes activities by up‐regulating expression of Nrf2 and its downstream components in wound tissue and/or H2O2‐treated endothelia. Meanwhile, H2 inhibited the overexpression of MCP‐1, E‐selectin, P‐selectin and ICAM‐1 in oxidant‐induced endothelia and reduced inflammatory cells infiltration and proinflammatory cytokines (TNF‐α, IL‐1, IL‐6 and IL‐8) production in the wound. Furthermore, H2 promoted the expression of pro‐healing factors (IL‐22, TGF‐β, VEGF and IGF1) and inhibited the production of MMP9 in wound tissue in parallel with acceleration of cutaneous collagen synthesis. Taken together, these data indicated that H2 inhalation suppressed the formation of pressure ulcer in a mouse model. Molecular hydrogen has potentials as a novel and alternative therapy for severe pressure ulcer. The therapeutic effects of molecular hydrogen might be related to its antioxidant, anti‐inflammatory, pro‐healing actions. 相似文献
80.
Chinnamaruthu Jayachitra Senguttuvan Jamuna Mohammad Ajmal Ali Subramaniam Paulsamy Fahad M.A. Al-Hemaid 《Saudi Journal of Biological Sciences》2018,25(2):293-297
Cissus setosa is an indigenous medicinal herb commonly used for the treatment of gastro ulcers. In the current investigation the aerial methanolic extract of C. setosa was investigated for their antiulcer activity using pylorus ligation and ethanol in experimental rats. The extract was administered at the doses of 200 and 400 mg/kg b.w. orally for 3 days. However, higher dose of the extract subsequently reduced gastric ulcer induced aberrations by pylorus ligation (70.05%) and ethanol (78.16%) as judged by their altered biochemical parameters such as free acidity, total acidity, total carbohydrate, total protein and pepsin activity. Furthermore, macroscopic examination of rat’s stomach also showed that the pretreatment with methanolic extract notably lowered the pylorus ligation and ethanol induced ulcers. As perceived in the present study, evidently, our findings basically supports the potency of the methanol extracts of C. setosa to treat gastrointestinal related disorders, thus lends pharmacological credence to the suggested folklore use. 相似文献