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161.
ABSTRACT: BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by progressive development of airflow limitation that is poorly reversible. Because of a poor understanding of COPD pathogenesis, treatment is mostly symptomatic and new therapeutic strategies are limited. There is a direct relationship between the severity of the disease and the intensity of the inflammatory response. Besides smoking, one of the hypotheses for the persistent airway inflammation is the presence of recurrent infections. Macrolide antibiotics have bacteriostatic as well as anti-inflammatory properties in patients with cystic fibrosis and other inflammatory pulmonary diseases. There is consistent evidence that macrolide therapy reduces infectious exacerbations, decreases the requirement for additional antibiotics and improves nutritional measures. Because of these positive effects we hypothesised that maintenance macrolide therapy may also have beneficial effects in patients with COPD who have recurrent exacerbations. The effects on development of bacterial resistance to macrolides due to this long-term treatment are unknown. Until now, studies investigating macrolide therapy in COPD are limited. The objective of this study is to assess whether maintenance treatment with macrolide antibiotics in COPD patients with three or more exacerbations in the previous year decreases the exacerbation rate in the year of treatment and to establish microbial resistance due to the long-term treatment. Methods/design The study is set up as a prospective randomised double-blind placebo-controlled single-centre trial. A total of 92 patients with COPD who have had at least three exacerbations of COPD in the previous year will be included. Subjects will be randomised to receive either azithromycin 500 mg three times a week or placebo. Our primary endpoint is the reduction in the number of exacerbations of COPD in the year of treatment. DISCUSSION: We investigate whether long-term therapy with macrolide antibiotics can prevent exacerbations in patients with COPD. Additionally, our study aims to assess the effect of long-term use of macrolide on the development of antimicrobial resistance and on inflammatory parameters related to COPD. We believe this study will provide more data on the effects of macrolide treatment in patients in COPD and will add more knowledge on its working mechanisms. Trial registration www.clinicaltrials.gov NCT00985244.  相似文献   
162.
Osteoporosis is a systemic skeletal disorder characterized by decreased bone mass and deterioration of bony microarchitecture. It is a chronic condition of multifactorial etiology and is usually clinically silent until a fracture occurs. Fatty liver disease can range from fatty liver alone (steatosis) to fatty liver associated with inflammation. This state can occur with the use of alcohol (alcohol-related fatty liver) or in the absence of alcohol (NASH). It has been known that liver has important a role in bone metabolism via production of the active vitamin D. Here, we have discussed whether a relationship between NASH and osteoporosis.  相似文献   
163.

Background  

Quantitative real-time PCR (qPCR) has been the method of choice for the quantification of mRNA. Due to the various artifactual factors that may affect the accuracy of qPCR, internal reference genes are most often used to normalize qPCR data. Recently, many studies have employed computer programs such as GeNorm, BestKeeper and NormFinder in selecting reference genes, but very few statistically validate the outcomes of these programs. Thus, in this study, we selected reference genes for qPCR of liver and ovary samples of yellow (juvenile), migratory (silver) and 11-KT treated juveniles of New Zealand shortfinned eels (Anguilla australis) using the three computer programs and validate the selected genes statistically using REST 2009 software and the Mann-Whitney test. We also tested for the repeatability of use for the best reference genes by applying them to a data set obtained in a similar experiment conducted the previous year.  相似文献   
164.
165.
Myocardial infarction (MI) is an instant ischemic death of cardiomyocytes that remains a major global cause of mortalities. MI is accompanied by oxidative, inflammatory, apoptotic, and fibrotic insults. Protocatechuic acid (PCA) is a polyphenolic compound with various potent biological activities. In this study, we explored the possible cardioprotective role of PCA against isoproterenol (ISO)-mediated MI. Rats were either injected with ISO (85 mg/kg, subcutaneously) or pretreated with PCA (100 or 200 mg/kg, orally). PCA supplementation markedly normalized ISO-induced disturbed cardiac function markers (creatine kinase-MB, lactate dehydrogenase, and troponin T). Notably, PCA administration exerted remarkable increases in glutathione and its derived enzymes, superoxide dismutase, and catalase, as well as decreases in malondialdehyde and nitric oxide levels in the injured cardiac tissue. The molecular findings validated the augmented cellular antioxidative capacity by PCA via increasing the gene expressions of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1. The cardioprotective efficacy of PCA extended to suppress cardiac inflammation as demonstrated by the decreased levels of tumor necrosis factor-alpha, interleukin-1 beta, and nuclear factor kappa B. Additionally, PCA prevented cardiomyocyte loss and fibrosis by decreasing Bax, caspase-3, transforming growth factor-β1 and matrix metalloproteinase-9, and enhancing B-cell lymphoma 2 and tissue inhibitors of metalloproteinase-3. The cardiac histological screening further confirmed the PCA's protective action. The obtained data recommend PCA as an alternative therapeutic agent to attenuate the molecular, biochemical, and histological alterations associated with MI development.  相似文献   
166.
BackgroundInflammation is recognized as a hallmark feature of cancer development and progression. The aim of our study was to investigate the significance of serum nuclear factor kappa-B (NF-κB) levels as a circulating marker in the monitoring of inflammation in breast and colon cancer; to show the relationship between NF-κB with inflammatory parameters as tumour necrosis factor-α (TNF-α), soluble TNF-related apoptosis-inducing ligand (sTRAIL), interleukin-6 (IL-6), pentraxin-3 (PTX-3), procalcitonin (PCT), and C-reactive protein (CRP) levels.MethodsSerum NF-κB, TNF-α, sTRAIL, IL-6, PTX-3, PCT, and serum CRP levels were measured using enzyme-linked immunosorbent assay (ELISA) in 40 patients with breast cancer, 40 patients with colon cancer and 30 healthy controls.ResultsThe serum NF-κB, TNF-α, IL-6, PTX-3, PCT, and serum CRP concentration was significantly higher, and the serum sTRAIL concentration was significantly lower in the patients with breast and colon cancer than in healthy controls. NF-κB was positively correlated with CRP and negatively correlated with sTRAIL.ConclusionsThese results suggest that increased NF-κB may decrease the clinical efficacy of sTRAIL in solid tumour cells. There is a relationship between inflammation and carcinogenesis so that the development of cancer occurs with chronic inflammation in breast and colon. The study results have shown that colon and breast cancer patients have increased systemic inflammation, as measured by increased circulating cytokines, and acute-phase proteins, or by abnormalities in circulating cells. NF-κB may combine with other markers of the systemic inflammatory response in prognostic scores in cancer. In addition to surgical resection of the tumour, and conventional radio and chemotherapy for cancer treatment, the use of sTRAIL or other agonists for cancer therapy appeared a new potential therapy.  相似文献   
167.
Predictions of added resistance and the effective power of ships were made for varying barnacle fouling conditions. A series of towing tests was carried out using flat plates covered with artificial barnacles. The tests were designed to allow the examination of the effects of barnacle height and percentage coverage on the resistance and effective power of ships. The drag coefficients and roughness function values were evaluated for the flat plates. The roughness effects of the fouling conditions on the ships’ frictional resistances were predicted. Added resistance diagrams were then plotted using these predictions, and powering penalties for these ships were calculated using the diagrams generated. The results indicate that the effect of barnacle size is significant, since a 10% coverage of barnacles each 5 mm in height caused a similar level of added power requirements to a 50% coverage of barnacles each 1.25 mm in height.  相似文献   
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