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961.
Garnier Y Kadyrov M Gantert M Einig A Rath W Huppertz B 《European journal of obstetrics, gynecology, and reproductive biology》2008,140(2):152-157
OBJECTIVES: Antenatal infections are associated with an increased risk of perinatal morbidity and mortality. Systemic application of endotoxins to the fetus results in an increase in placental vascular resistance and chronic reduction in umbilical blood flow. We studied morphological alterations of the placenta in response to fetal inflammation in the preterm sheep. STUDY DESIGN: Therefore, 14 fetal sheep were chronically instrumented at a mean gestational age of 107+/-1 days (term is 147 days). Four days after surgery fetuses received 100 ng lipopolysaccharide (LPS; n=8) or saline (control; n=6) intravenously. Fetal heart rate and arterial blood pressure were monitored continuously while blood gases and acid-base balance were measured at time points 0, +1, +3, +6, +12, +24, +48 and +72 h. Three days after LPS application placental cotyledons were analyzed by immunohistochemistry and morphometry. Different primary antibodies like AE 1 and AE 3 against cytokeratins were used. Secondary antibodies were visualized with 3-amino-9-ethylcarbazole (AEC) or using the Vectastain kit (Vector Laboratories, Burlingame, CA). Double staining was carried out first by utilizing Vectastain kit (black), followed by AEC staining (red). Counterstaining was performed with haematoxylin. RESULTS: Fetal tachycardia and hypertension were induced transiently during the first 12h after LPS application. Fetuses suffered from mild hypoxaemia while acidemia was absent. Morphometry revealed a non-significant shift in the relation of maternal and fetal placental compartments towards the maternal parts in response to LPS treatment. Endotoxin induced an increased proliferation in both compartments of the placenta with a 3.2-fold increase on the maternal and a 1.8-fold increase on the fetal side. CONCLUSIONS: Systemic endotoxin exposure of the preterm fetal sheep leads to a change in the gross organization of the placenta and changes in the proliferation patterns in both placental compartments. These rearrangements inside the placenta may disturb its organ function and subsequently lead to fetal morbidity associated with the fetal inflammatory response syndrome and chronic placental dysfunction, respectively. 相似文献
962.
963.
964.
Castardo JC Prudente AS Ferreira J Guimarães CL Monache FD Filho VC Otuki MF Cabrini DA 《Journal of ethnopharmacology》2008,118(3):405-411
Garcinia gardneriana (Planch. & Triana) Zappi (Clusiaceae) is widely distributed in Brazil and used in folk medicine to treat inflammation, pain, and urinary tract and other infections. However, very few studies have analyzed these therapeutic effects. In this study, the anti-inflammatory effects of the hydroalcoholic extracts from Garcinia gardneriana (HEGG) and some of its isolated biflavonoids were evaluated. The results showed that HEGG from the leaves, bark and seeds reduced carrageenan-induced mouse paw inflammation, in addition to diminishing the myeloperoxidase activity in the stimulated tissues. The reduction of neutrophil infiltration by treatment with the HEGG from leaves was confirmed by histology. The leaf extract also reduced the paw oedema evoked by bradykinin, histamine, prostaglandin E2 and 12-O-tetradecanoylphorbol acetate. However, it partially decreased substance P and compound 48/80-caused paw oedema, without any influence on the arachidonic acid-induced oedema. Both of the isolated compounds, fukugetin and GB-2a, prevented the carrageenan-induced paw oedema. In conclusion, this study showed important anti-inflammatory effects of HEGG through its interaction with different intracellular signaling pathways, without interfering with the formation of arachidonic acid (AA) metabolites. These characteristics, in addition to the wide distribution and culturing ease of the plant, confirm its popular use and highlight its promise in the development of new anti-inflammatory drugs. 相似文献
965.
活血解毒中药有效部位对ApoE基因敲除小鼠血脂和动脉粥样硬化斑块炎症反应的影响 总被引:1,自引:0,他引:1
目的 观察活血(三七总皂苷)、解毒(黄连提取物)、活血解毒中药有效部位(虎杖提取物、大黄醇提物)对ApoE基因敲除小鼠血脂和主动脉粥样斑块炎症反应的影响。 方法 ApoE基因敲除小鼠予高脂饮食喂养26周,给药13周后,处死检测血脂,并取出心脏及主动脉,石蜡包埋,取主动脉根部4个切面,分别行HE染色、Movat染色,测量并计算脂质核心占斑块总面积的百分比以及斑块内脂质成分/胶原成分比值;每个样本取4个切面的平均值。免疫组织化学染色法观察小鼠主动脉根部粒细胞/巨噬细胞集落刺激因子(GM-CSF)、肿瘤坏死因子α(TNF-α)的表达。结果 给药13周后,斑块内脂质核心面积、斑块内脂质成分/胶原成分比值,中药各给药组与模型组比较均有不同程度降低(P<0.01),其中活血解毒中药虎杖提取物降低最为显著,并与活血中药三七总皂苷组、解毒中药黄连提取物组比较亦具有显著差异(P<0.05)。虎杖提取物、黄连提取物、三七总皂苷均具有程度不同的调脂作用,但仍以虎杖提取物的作用最为显著;各给药组只有大黄醇提物组的TNF-α表达减少,与模型组比较差异有统计学意义(P<0.05),中药各组GM-CSF表达减少,与模型组比较,差异有统计学意义(P<0.05)。 结论 活血、解毒及活血解毒中药有效部位三七总皂苷、黄连提取物、虎杖提取物、大黄醇提物在临床推荐剂量上均可通过改善斑块内部成分来稳定易损斑块,其中,兼有活血和解毒作用的中药虎杖提取物、大黄醇提物效果最为显著。其机制可能与调节脂质代谢和抑制炎症反应有关。 相似文献
966.
Chien-Li Chen Pei-Yu Hsu Tzu-Ming Pan 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(1):83
Ulcerative colitis (UC) is a form of inflammatory bowel disease (IBD) whose exact cause is still unclear. Disruption of the intestinal microflora is considered one of the main causes of the disease. Lactobacillus paracasei subsp. paracasei NTU 101 (NTU 101) is a multifunctional strain that has been shown in previous studies to possess anti-inflammatory properties and to exert a modulatory effect on intestinal bacteria associated with certain pathogenic mechanisms of IBD. In the current study, we investigated the effects of NTU 101 on dextran sulfate sodium (DSS)-induced colitis in a mouse model. Colitis was induced in male C57BL/6 mice (total number n = 60) via dissolved DSS in drinking water on days 15–21 of the experiment. The effects of continuous 25 d feeding (days 0–25) of either a half or a full dose [2.3 × 109 colony-forming units (CFU)/kg body weight (BW)/d and 4.5 × 109 CFU/kg BW/d, respectively] of NTU 101 was evaluated. Lactobacillus rhamnosus BCRC 16000 (BCRC 16000) and L. paracasei subsp. paracasei BCRC 14023 (BCRC 14023) strains were given to control groups. The results indicated that NTU 101 powder improved anti-oxidant capacity, reduced pro-inflammatory cytokine levels, increased anti-inflammatory cytokine levels, and slightly ameliorated body weight loss in DSS-treated mice during the final days of the study. This indicated that NTU 101 powder can relieve the clinical symptoms of DSS-induced colitis in mice. 相似文献
967.
目的:探讨高温与脂多糖(LPS)复合应激大鼠血清天门冬酸氨基转移酶(AST)含量的变化特点.方法:雄性SPF级Wistar大鼠64只随机均匀分为常温 生理盐水组(C组),高温 生理盐水组(H组),常温 LPS组(L组),高温 LPS组(HL组).置动物于模拟气候舱,HL和H组暴露环境干球温度(Tdb)为(35.0±0.5)℃,L和C组Tdb为(26±0.5)℃;HL和L组动物经尾静脉注射LPS 10 mg/kg,H和C组动物经尾静脉注射9 g/L NaCl 10 mL/kg.持续监测动物平均动脉压(MAP)的动态变化,检测动物应激0,40,80,120 min时血清AST等物质含量的变化.结果:AST在不同温度、时间、药物水平间存在统计学差异(P<0.01);时间与温度、时间与药物、温度与药物交互作用有统计学意义(P<0.05),120 min时相点HL组动物血清AST含量高于其余3组,差异有统计学意义(P<0.01);AST水平与MAP存在负相关关系(r=-0.818,P=0.029).结论:高温与LPS复合应激可促发、扩大全身炎症反应综合征. 相似文献
968.
目的 探讨蕨麻多糖(PAP)对大鼠脑缺血再灌注损伤的保护作用及其机制.方法 将Wistar 雄性大鼠120只,随机分为6组:假手术组、模型组、尼莫地平组(12 mg/kg)和蕨麻多糖高[160 mg/(kg·d)]、中[80 mg/(kg·d)]、低[40 mg/(kg·d)]剂量组.采用线栓法栓塞大鼠大脑中动脉建立大鼠脑缺血再灌注损伤模型,从术前7d开始,每天1次,再灌注后1h给药1次.再灌注结束后进行神经功能缺失症状评分;分别用化学比色法测定脑组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和丙二醛(MDA)含量;酶联免疫吸附法(ELISA)测定肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)和白细胞介素-10(IL-10)含量.结果 与假手术组比较,模型组大鼠神经功能缺失症状明显,模型组大鼠脑组织SOD、GSH-Px、IL-10含量明显降低,MDA、TNF-α、IL-1β含量显著升高(P<0.05);与模型组比较,蕨麻多糖各剂量组大鼠神经功能缺失症状明显改善,蕨麻多糖能降低脑组织MDA、TNF-α和IL-1β含量,升高SOD、GSH-Px和IL-10含量(P<0.05);并且这种影响与蕨麻多糖剂量存在对应关系.结论 蕨麻多糖对大鼠脑缺血再灌注损伤具有一定保护作用,其机制可能与其提高脑组织抗氧化能力、抑制炎症因子有关. 相似文献
969.
目的 探讨单磷酸腺苷激活蛋白激酶(AMPK)活化对慢性间歇缺氧大鼠胰岛素抵抗和炎症因子的作用及其机制.方法 建立慢性间歇缺氧大鼠模型模拟阻塞性睡眠呼吸暂停综合征(OSAS),将36只雄性SD大鼠分为常氧对照组、2周间歇缺氧组、8周间歇缺氧组.观察AMPK激动剂和AMPK抑制剂作用不同缺氧程度的大鼠体内炎症介质、血脂、脂联素、瘦素及胰岛素抵抗水平,监测大鼠脂肪组织AMPK、葡萄糖转运蛋白(GLUT4)水平,并进行统计学分析.结果 间歇缺氧大鼠总胆固醇、三酰甘油、肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-2、核因子κB (NF-κB)、缺氧诱导因子(HIF-1)显著高于对照组(P<0.05);脂联素、瘦素及胰岛素抵抗指数显著低于对照组(P<0.05).使用AMPK激活剂后的大鼠体内炎症因子释放减少,脂联素、瘦素含量增加,血脂、胰岛素抵抗情况较前有改善,GLUT4水平增加.而使用AMPK抑制剂处理后大鼠体内炎症因子、脂联素、瘦素水平均上升,胰岛素抵抗更严重,GLUT4水平也进一步下降.结论 AMPK能够减少炎症介质的释放,促进脂联素、瘦素的释放,增加GLUT4水平,改善胰岛素抵抗,从而调节能量代谢及炎症介质,为临床治疗OSAS相关疾病提供新的思路与靶点. 相似文献
970.
蝮蛇伤病人中毒程度与血清C反应蛋白的关系 总被引:1,自引:0,他引:1
目的观察70例蝮蛇咬伤患者血清C反应蛋白(CRP)水平的变化,探讨其与蝮蛇伤病情严重程度及与SIRS(全身炎症反应综合征)、MODS(多器官功能障碍综合征)发生的关系,分析蝮蛇伤患者血清C反应蛋白的变化对疾病的病情及顸后估计的意义。方法根据毒蛇咬伤的临床分型及严重程度评分标准,按患者入院时中毒的程度设轻型、重型、危重型,比较各型之间血清C反应蛋白水平的差异性;根据ACCP/SCCM提出的SIRS诊断标准,将患者分为SIRS组与非SIRS组,比较两组之间血清C反应蛋白水平的差异性;根据MODS诊断标准,将患者分为MODS组与非MODS组,比较两组之间血清酶及血清c反应蛋白水平的差异性。结果重型、危重型患者血清C反应蛋白与轻型比较,差异有显著性(P〈0.01);SIRS组与非SIRS组血清C反应蛋白比较,差异存在显著性(P〈0.05);MODS组与非MODS组血清C反应蛋白比较,差异存在显著性(P〈0.05);SIRS组MODS的发生率明显高于非SIRS组,SIRS组与非SIRS组MODS的发生率比较,差异存在高度显著性(X^2=19。73,P〈0.001)。结论蝮蛇咬伤患者病情程度越重,其血清C反应蛋白升高得越明显;蝮蛇咬伤患者并发SIRS时,血清CRP升高明显,发生MODS几率升高。 相似文献