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41.
The effects of intra-articular injection, on two occasions, 3 weeks apart, of the contrast agent Urografin on the cytological and biochemical characteristics of synovial fluid (SF) were examined in two studies in dogs. The first study provided baseline data in two non-medicated dogs. The second study used a cross-over design whereby 4 dogs received a 7-day oral treatment with either a placebo or meloxicam (0.2 mg/kg body weight daily) with a washout period of 3 weeks, in order to determine the effect of this new non-steroidal anti-inflammatory drug (NSAID) on the response to Urografin injection. SF samples were collected under general anaesthesia prior to and at 24 and 72 h after each Urografin injection. The volume, relative viscosity, white blood cell count and concentrations of protein, lactate dehydrogenase (LDH) and hyaluronic acid of these samples were determined.The results from both studies indicate that intra-articular injection of Urografin provoked a mild local transient inflammatory response, the most dramatic evidence of which was an increase in the white blood cell count in the SF after 24 h. In the second study, comparison of the synovial fluid measurements of the placebo-treated dogs at 24 h after Urografin injection with those prior to injection revealed significant increases in SF volume, white blood cell count, protein concentration and LDH activity and a significant reduction in relative viscosity. At 72 h after injection, only the white blood cell count and relative viscosity were significantly different from the pre-injection values. All of these measurements were, however, associated with high coefficients of variation, which must be taken into account in assessing the usefulness of the model for drug-testing purposes. Nevertheless, the administration of meloxicam significantly reduced the SF volume and white blood cell count at 24 h relative to the effects of concurrent placebo treatment. The general health status of the animals was not disturbed at any time as assessed by clinical and haematological observations. No adverse reactions were observed.Abbreviations LDH lactate dehydrogenase - NSAID non-steroidal anti-inflammatory drug - SF synovial fluid - WBC white blood cell count  相似文献   
42.
Inflammation causes epithelial cell sloughing and basement membrane (BM) exposure in canine pulmonary eosinophilia (PE), leading to degradation of the epithelial cell attachment component, laminin-5 gamma2-chain, into small molecular weight fragments. The subsidence of inflammation after treatment down-regulates degradation. Laminin-5 gamma2-chain levels and molecular forms in bronchoalveolar lavage fluid (BALF) were analysed semiquantitatively by Western immunoblotting to compare PE affected (n=20) and healthy dogs (n=16) as well as PE dogs (n=6) before and after corticosteroid treatment. PE dogs expressed significantly elevated levels of total (P<0.01), 36 kDa (P<0.05) and 53 kDa (P<0.05) laminin-5 gamma2-fragments. The 36 Da fragment decreased significantly (P<0.05) after treatment. The laminin-5 gamma2-chain degradation products may be linked to epithelial cell sloughing and BM exposure or healing.  相似文献   
43.
建立动脉粥样硬化(AS)大鼠模型,灌胃阿魏酸钠(SF),探讨其炎症以及干预炎症反应的机制。SD大鼠随机分为正常组、模型组、阳性组[辛伐他汀2mg.(kg.d)-1],SF 3个剂量组[80、40、20mg.(kg.d)-1]。建模第2周开始给药,连续8周。全自动生化仪测定血清TC、TG、LDL-C、HDL-C含量,酶联免疫吸附法检测血清ox-LDL、IL-10、TNF-α、CRP含量;取主动脉及肝脏制作切片,显微镜观察组织形态结构。结果表明:模型大鼠血清TC、TG、LDL-C均显著升高,HDL-C有所下降,分别与正常组比较均有显著差异(P<0.01);SF可以降低动脉粥样硬化大鼠血清TC、TG含量(P<0.01),提高HDL-C和IL-10含量(P<0.01),且可降低ox-LDL、TNF-α、CRP水平(P<0.01)。说明AS形成伴随炎症因子异常,SF通过抑制炎症因子、减少ox-LDL生成,调节血脂,减少泡沫细胞形成,进而减轻AS斑块形成,改善血管壁和肝脏脂肪变性的病理改变,从而预防AS。  相似文献   
44.
目的了解鼓室炎症对自体骨塑形听骨链重建术后听力的影响。方法 45例自体骨塑形听骨链重建术的患者,根据鼓室炎症轻重程度分为炎症轻组(25例)及炎症重组(20例)。炎症轻组鼓室黏膜充血、光滑、无增厚;炎症重组鼓室黏膜肥厚、粘连、肉芽增生。比较两组术前后的平均气骨导差。结果炎症轻组术后平均气骨导差比术前减少(17.87±7.11)dB,而炎症重组减少(9.65±5.13)dB,两组手术前后平均气骨导差值的差异有统计学意义(P〈0.01)。结论鼓室炎症的轻重程度是影响术后听力的重要原因。  相似文献   
45.
Reasons for performing study: The pathophysiological events inhibited by prophylactic digital hypothermia that result in reduction of the severity of acute laminitis are unknown. Objectives: To determine if digital hypothermia inhibits lamellar inflammatory signalling during development of oligofructose (OF) induced laminitis. Methods: Fourteen Standardbred horses were given 10 g/kg bwt OF by nasogastric tube with one forelimb (CRYO) continuously cooled by immersion in ice and water and one forelimb (NON‐RX) at ambient temperature. Lamellae were harvested prior to the onset of lameness (24 h post OF administration, DEV group, n = 7) or at the onset of lameness (OG1 group, n = 7). Lamellar mRNA was purified and cDNA produced for real time‐quantitative PCR analysis of mRNA concentrations of cytokines (IL‐6, IL‐1β, IL‐10), chemokines (CXCL1, CXCL6, CXCL8/IL‐8, MCP‐1, MCP‐2), cell adhesion molecules (ICAM‐1, E‐selectin), COX‐2 and 3 housekeeping genes. Data were analysed (NON‐RX vs. CRYO, NON‐RX vs. archived control [CON, n = 7] lamellar tissue) using nonparametric tests. Results: Compared with CON, the OG1 NON‐RX had increased (P<0.05) lamellar mRNA concentrations of all measured mediators except IL‐10, IL‐1β and MCP‐1/2, whereas only CXCL8 was increased (P<0.05) in DEV NON‐RX. Within the OG1 group, CRYO limbs (compared with NON‐RX) had decreased (P<0.05) mRNA concentrations of the majority of measured inflammatory mediators (no change in MCP‐1 and IL‐10). Within the DEV group, mRNA concentrations of CXCL‐1, ICAM‐1, IL‐1β, CXCL8 and MCP‐2 were decreased (P<0.05) and the anti‐inflammatory cytokine IL‐10 was increased (compared with NON‐RX limbs; P<0.05). Conclusions: Digital hypothermia effectively blocked early lamellar inflammatory events likely to play an important role in lamellar injury including the expression of chemokines, proinflammatory cytokines, COX‐2 and endothelial adhesion molecules. Potential relevance: This study demonstrates a potential mechanism by which hypothermia reduces the severity of acute laminitis, and may help identify molecular targets for future laminitis intervention.  相似文献   
46.
Reasons for performing study: Accurate measurement of plasma fibrinogen concentrations is an important tool for assessment of horses with inflammatory diseases. Objectives: To determine the precision and accuracy of a benchtop instrument using both fresh and frozen equine plasma by comparing the plasma fibrinogen concentration measured by a benchtop instrument to 2 separate laboratory standard methods (ACL 100 and STA Compact) for fibrinogen measurement. Methods: Accuracy and precision of the VSPro was evaluated using both human fibrinogen standards and samples from horses. Fifty frozen samples from horses with gastrointestinal disease had the fibrinogen concentration measured using the ACL 1000 and the VSPro. Fifty fresh samples were collected from hospitalised horses and fibrinogen concentration was measured using the STA Compact coagulation machine and the VSPro. Correlations for measurements were performed, as well as Bland‐Altman analysis. Results: Coefficients of variability for the VSPro ranged from 7% to 15%. The VSPro fibrinogen values were well correlated to both the ACL 1000 (r = 0.94, P<0.001) and the STA Compact measurements (r = 0.926, P<0.001). Bland‐Altman analysis showed a mean bias of ‐0.83 g/l (95% confidence interval ‐2.03–0.324 g/l) for the ACL 1000 and a mean bias of ‐0.024 g/l (95% confidence interval ‐1.434–1.386 g/l) for the STA Compact. Conclusions: The VSPro appears to have adequate accuracy and precision for clinical measurement of plasma fibrinogen concentrations. Potential relevance: The VSPro provides a measurement of equine plasma fibrinogen concentration using a benchtop instrument with a rapid test time that has comparable accuracy to the fibrinogen concentration obtained from reference laboratories.  相似文献   
47.
Reasons for performing study: A significant proinflammatory response is known to occur in the forelimb lamina after carbohydrate administration. As the hindlimbs are often less affected by laminitis compared with the forelimbs, we assessed hindlimb inflammatory response in the early stages of carbohydrate‐induced laminitis to determine whether differences in the response existed. Objective: To determine whether a similar proinflammatory response occurs in the hindlimb laminae to that previously reported for the forelimb. Methods: Archived laminar samples from 12 horses administered 17.6 g of starch (85% corn starch, 15% wood flour)/kg bwt via nasogastric tube that were anaesthetised either after developing a temperature >38.9°C (DEV; n = 6) or at the onset of Obel grade 1 lameness (OG1; n = 6) were used in addition to 6 control horses (CON) that were anaesthetised 24 h after administration of water. Real‐time quantitative polymerase chain reaction for selected proinflammatory mediators and MAC387 immunohistochemistry were performed. The data were analysed nonparametrically to compare groups. Results: Increases in laminar MAC387‐positive leucocytes and laminar messenger ribonucleic acid (mRNA) concentrations (P<0.05) for interleukin‐1β, interleukin‐6, cyclo‐oxygenase‐2, chemokine (C‐X‐C motif)ligand (CXCL)1 and CXCL8 were present in both fore‐ and hindlimb laminae from horses with OG1 lameness. Both CXCL1 and CXCL8 were also increased in forelimb and hindlimb laminae in the DEV horses. Conclusions: Administration of carbohydrate resulted in a similar inflammatory response in the hindlimb laminae to that previously reported for the forelimb laminae. These findings suggest that other factors, such as weightbearing, may play an important role in the development of laminitis after a systemic inflammatory condition develops. Potential relevance: Evidence of inflammation in the hindlimb laminae suggests that the hindfeet should be addressed in the septic horse at risk for laminitis; however, laminitis is often less severe in the hindlimbs due to other factors, such as weightbearing and hoof angle.  相似文献   
48.
Relmβ亦称发现于炎症带2(found in inflammatory zone2,FIZZ2),是一种富含半胱氨酸的分泌蛋白。目前的研究表明,Relmβ在许多方面发挥着非常重要的作用,包括胰岛素抵抗,抵制肠腔寄生线虫的感染,预测胃肠道肿瘤的发生,促进小鼠结肠炎和回肠炎模型中的炎症反应,诱导肺部纤维化、缺氧肺血管的重建,促进气道重塑等。通过对Relmβ分子的结构、表达分布、生物学功能的研究进展进行归纳,为Relmβ分子在生物学和医学方面更深入的研究提供参考。  相似文献   
49.
中药"乳源康"药理作用研究   总被引:7,自引:1,他引:6  
为了对“乳源康”的毒理药理学进行研究,进行4种试验——急性毒性试验、抗菌试验、局部刺激试验、抗炎试验。结果表明,①“乳源康”的小鼠口服LD50为36.80g/kg体重,腹腔注射LD50为13.85g/kg体重;②“乳源康”对乳房炎致病菌金黄色葡萄球菌、链球菌等有较强的抑制作用;③无明显刺激作用;④“乳源康”注射液与氢化可的松的消炎效果相同。“乳源康”治疗奶牛乳房炎具有高效、安全、低毒、使用方便、无化学药物和抗生素残留的优点,临床应用对治疗奶牛乳房炎、解决乳制品中的抗生素类药物残留以及病原微生物的耐药性问题具有重要意义。  相似文献   
50.
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