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141.
Robert A Clayton Colin AJ Dick Alison Mackenzie Michiaki Nagasawa Deirdre Galbraith Stuart F Hastings Simon J MacKenzie 《Respiratory research》2004,5(1):4
BackgroundThe anti-inflammatory effects of the selective phosphodiesterase (PDE) inhibitors cilostazol (PDE 3), RO 20-1724 (PDE 4) and sildenafil (PDE 5) were examined in a murine model of allergic asthma. These compounds were used alone and in combination to determine any potential synergism, with dexamethasone included as a positive control.MethodsControl and ovalbumin sensitised Balb/C mice were administered orally with each of the possible combinations of drugs at a dose of 3 mg/Kg for 10 days.ResultsWhen used alone, RO 20-1724 significantly reduced eosinophil influx into lungs and lowered tumour necrosis factor-α, interleukin-4 and interleukin-5 levels in the bronchoalveolar lavage fluid when compared to untreated mice. Treatment with cilostazol or sildenafil did not significantly inhibit any markers of inflammation measured. Combining any of these PDE inhibitors produced no additive or synergistic effects. Indeed, the anti-inflammatory effects of RO 20-1724 were attenuated by co-administration of either cilostazol or sildenafil.ConclusionsThese results suggest that concurrent treatment with a PDE 3 and/or PDE 5 inhibitor will reduce the anti-inflammatory effectiveness of a PDE 4 inhibitor. 相似文献
142.
Jurriaan J H?lzenspies Willem Stoorvogel Ben Colenbrander Bernard AJ Roelen Dagmar R Gutknecht Theo van Haeften 《BMC developmental biology》2009,9(1):8
Background
Mammalian oocytes acquire competence to be fertilized during meiotic maturation. The protein kinase CDC2 plays a pivotal role in several key maturation events, in part through controlled changes in CDC2 localization. Although CDC2 is involved in initiation of maturation, a detailed analysis of CDC2 localization at the onset of maturation is lacking. In this study, the subcellular distribution of CDC2 and its regulatory proteins cyclin B and SPDY in combination with several organelle markers at the onset of pig oocyte maturation has been investigated. 相似文献143.
144.
Janneke Anink Charlotte M Nusman Lisette WA van Suijlekom-Smit Rick R van Rijn Mario Maas Marion AJ van Rossum 《Arthritis research & therapy》2014,16(4)
Introduction
Chronic inflammation combined with glucocorticoid treatment and immobilization puts juvenile idiopathic arthritis (JIA) patients at risk of impaired growth and reduced bone mineral density (BMD). Conventional methods for evaluating bone age and BMD are time-consuming or come with additional costs and radiation exposure. In addition, an automated measurement of bone age and BMD is likely to be more consistent than visual evaluation. In this study, we aimed to evaluate the feasibility of an automated method for determination of bone age and (cortical) bone mineral density (cBMD) in severely affected JIA patients. A secondary objective was to describe bone age and cBMD in this specific JIA population eligible for biologic treatment.Methods
In total, 69 patients with standard hand radiographs at the start of etanercept treatment and of calendar age within the reliability ranges (2.5 to 17 years for boys and 2 to 15 years for girls) were extracted from the Dutch Arthritis and Biologicals in Children register. Radiographs were analyzed using the BoneXpert method, thus automatically determining bone age and cBMD expressed as bone health index (BHI). Agreement between measurements of the left- and right-hand radiographs and a repeated measurement of the left hand were assessed with the intraclass correlation coefficient (ICC). Regression analysis was used to identify variables associated with Z-scores of bone age and BHI.Results
The BoneXpert method was reliable in the evaluation of radiographs of 67 patients (radiographs of 2 patients were rejected because of poor image quality). Agreement between left- and right-hand radiographs (ICC = 0.838 to 0.996) and repeated measurements (ICC = 0.999 to 1.000) was good. Mean Z-scores of bone age (−0.36, P = 0.051) and BHI (−0.85, P < 0.001) were lower compared to the healthy population. Glucocorticoid use was associated with delayed bone age (0.79 standard deviation (SD), P = 0.028), and male gender was associated with a lower Z-score of BHI (0.65 SD, P = 0.021).Conclusions
BoneXpert is an easy-to-use method for assessing bone age and cBMD in patients with JIA, provided that radiographs are of reasonable quality and patients’ bone age lies within the age ranges of the program. The population investigated had delayed bone maturation and lower cBMD than healthy children.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0424-1) contains supplementary material, which is available to authorized users. 相似文献145.
146.
A Azzolini R Gianrossi S Livi M C Nizzo M Oliveri P Mangini 《Bollettino della Società italiana di biologia sperimentale》1982,58(14):891-894
In this paper we evaluated whether a block of cardiac H2 histamine receptors by ranetidine could modify some non-invasive indices of cardiac function: PEP/LVET, heart rate, blood pressure. Five healthy volunteers underwent studies in baseline conditions and 5, 10, 15, 30, 45 minutes following i.v. injections of 1, 5 m/g Kg of ranitidine. None of the studied parameters showed any significant variation at the various time intervals. Ranetidine does not appear to alter the cardiovascular function at the dose we used. 相似文献
147.
148.
F. L. Baker L. J. Sanger R. W. Rodgers K. Jabboury O. R. Mangini 《Cell proliferation》1995,28(1):1-15
Current methods for measuring the cell kinetics of human tumours are made and interpreted within the context of a simplistic two compartment model for cell proliferation, consisting of cells that are cycling and those that are not. It is now recognized that the non-cycling compartment of many tumours is heterogeneous, composed of non-reproductive end-stage cells and reproductive cells that are dormant/quiescent. We have developed an in vitro analysis that distinguishes for the first time quiescent reproductive cells from non-reproductive end-stage cells and have integrated this analysis with monolayer clonogenic and suicide assays to simultaneously quantitate the duration of the cell cycle and reproductive cells that are: cycling, quiescent, clonogenic, and non-reproductive end-stage cells. We have defined a new parameter, the Cycling Reproductive Fraction (CRF), which is the cycling cell population referenced specifically to the reproductive cell population. Measurements of CRF from 72 tumour biopsies and from 5 normal foreskins showed that CRF approached 100% in some tumours; however, CRF showed near normal values (< 1%) in others suggesting that cell cycle control may be maintained in some tumours. Because of CRF's improved specificity, we believe that CRF may enhance classification, prognostication, and the optimization and prediction of response to chemotherapy. 相似文献
149.
Fa-Guo Wang Ai-Hua Wang Cheng-Ke Bai Dong-Mei Jin Li-Yun Nie AJ Harris Le Che Juan-Juan Wang Shi-Yu Li Lei Xu Hui Shen Yu-Feng Gu Hui Shang Lei Duan Xian-Chun Zhang Hong-Feng Chen Yue-Hong Yan 《Plant Diversity》2022,44(2):141
Ferns and lycophytes have remarkably large genomes. However, little is known about how their genome size evolved in fern lineages. To explore the origins and evolution of chromosome numbers and genome size in ferns, we used flow cytometry to measure the genomes of 240 species (255 samples) of extant ferns and lycophytes comprising 27 families and 72 genera, of which 228 species (242 samples) represent new reports. We analyzed correlations among genome size, spore size, chromosomal features, phylogeny, and habitat type preference within a phylogenetic framework. We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size. Using the phylogeny, we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference. We found that 2C values had weak phylogenetic signal, whereas the base number of chromosomes (x) had a strong phylogenetic signal. Furthermore, our analyses revealed a positive correlation between genome size and chromosome traits, indicating that the base number of chromosomes (x), chromosome size, and polyploidization may be primary contributors to genome expansion in ferns and lycophytes. Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types; specifically, multinomial logistic regression indicated that species with larger 2C values were more likely to be epiphytes. Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes, whereas transitions to other habitat types occurred as the major clades emerged. Shifts in habitat types appear be followed by periods of genomic stability. Based on these results, we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history. 相似文献