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Nerve growth factor (NGF) promotes angiogenesis in the quail chorioallantoic membrane. 总被引:1,自引:0,他引:1
Philip Lazarovici Aviv Gazit Izabela Staniszewska Cezary Marcinkiewicz Peter I Lelkes 《Endothelium》2006,13(1):51-59
Angiogenesis, the formation of new blood vessels, is tightly regulated by growth factors, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF). The authors hypothesize that nerve growth factor (NGF), a well known neurotrophin, may play a direct angiogenic role. To test this hypothesis, the authors measured the effects of NGF on the natural vascularization of the quail chorioallantoic membrane (CAM). The angiogenic effect of NGF was compared to that of human recombinant VEGF165 (rhVEGF) and basic FGF (rhbFGF). In comparison to phosphate-buffered saline-treated controls, NGFs from different biological sources (mouse, viper, and cobra) increased the rate of angiogenesis in a dose-dependent fashion from 0.5 to 5 microg. For quantitative morphometry, grayscale images of the blood vessels end points of the CAM arteries were binarized for visualization and skeletonized for quantization by fractal analysis. In mouse NGF-treated embryos the fractal dimension (Df), indicative of arterial vessel length and density, increased to 1.266 +/- 0.021 compared to 1.131 +/- 0.018 (p < .001) for control embryos. This effect was similar to that of 0.5 microg rhVEGF (1.290 +/- 0.021, p < .001) and 1.5 microg rhbFGF (1.264 +/- 0.028, p < .001). The mouse NGF-induced angiogenic effect was blocked by 1 microM K252a (1.149 +/- 0.018, p < .001), an antagonist of the NGF/trkA receptor, but not by 1 microM SU-5416 (1.263 +/- 0.029, p < .001), the VEGF/Flk1 receptor antagonist, indicating a direct, selective angiogenic effect of NGF via quail embryo trkA receptor activation. These results confirm previous observations that NGF has angiogenic activity and suggest that this neurotrophin may also play an important role in the cardiovascular system, besides its well-known effects in the nervous system. The angiogenic properties of NGF may be beneficial in engineering new blood vessels and for developing novel antiangiogenesis therapies for cancer. 相似文献
3.
Artur Matysiak Wojciech Kordecki Cezary Sielużycki Norman Zacharias Peter Heil Reinhard König 《Psychophysiology》2013,50(7):627-639
Grand means of time‐varying signals (waveforms) across subjects in magnetoencephalography (MEG) and electroencephalography (EEG) are commonly computed as arithmetic averages and compared between conditions, for example, by subtraction. However, the prerequisite for these operations, homogeneity of the variance of the waveforms in time, and for most common parametric statistical tests also between conditions, is rarely met. We suggest that the heteroscedasticity observed instead results because waveforms may differ by factors and additive terms and follow a mixed model. We propose to apply the asinh‐transformation to stabilize the variance in such cases. We demonstrate the homogeneous variance and the normal distributions of data achieved by this transformation using simulated waveforms, and we apply it to real MEG data and show its benefits. The asinh‐transformation is thus an essential and useful processing step prior to computing and comparing grand mean waveforms in MEG and EEG. 相似文献
4.
Effect of nifedipine on interdigestive gallbladder volume and postprandial gallbladder emptying in man 总被引:3,自引:0,他引:3
Dr Krzysztof Jonderko Andrzej Nowak Anna Kasicka-Jonderko Zbigniew Śliwiński Cezary Kucio 《Digestive diseases and sciences》1991,36(10):1434-1440
The effect of two oral doses (10 and 20 mg) of nifedipine versus placebo on the fasted gallbladder volume and on the meal-induced gallbladder emptying was assessed according to a double-blind study protocol in 12 healthy volunteers. Eight subjects underwent three studies (with placebo and with both nifedipine doses), whereas in two subjects the effect of a 10-mg nifedipine dose, vs placebo and in two others the effect of a 20-mg nifedipine dose vs placebo was examined. The studies were performed on separate days, and the gallbladder volume was measured by means of real-time ultrasonography. Neither placebo nor 20 mg nifedipine per os elicited any significant change in the fasted gallbladder vlume. With 10 mg nifedipine per os a significant increase in the interdigestive gallbladder volume was observed: 22.9±2.9 cm3 before and 26.2±3.2 cm3 after the drug receipt (P<0.005). A trend towards an inhibition of the postprandial gallbladder emptying was observed with 10 mg nifedipineper os without, however, reaching the level of statistical significance. Following 20 mg nifedipineper os, a marked delay in the meal-stimulated gallbladder emptying occurred as reflected by a decrease in the gallbladder ejection fraction from 48.1±4.5% (placebo) to 26.4±5.0% (nifedipine) (P<0.02) at 30 min and from 54.0±3.6% (placebo) to 33.2±4.6% (nifedipine) (P<0.02) at 40 min after the test meal. We conclude that a therapeutic oral dosage of nifedipine has a significant relaxing effect on the human gallbladder. 相似文献
5.
Tarek El-Bialy Adel Alhadlaq Bryan Wong Cezary Kucharski 《Annals of biomedical engineering》2014,42(7):1406-1412
Dental pulp loss due to caries or pulpitis can affect the longevity of teeth. Dental pulp tissue engineering necessitates the use of progenitor cells that has the potential to differentiate into neural, vascular and odontoblasts like cells. Previous reports have shown that human gingival progenitor cells (HGPCs) can be differentiated into different cell types; however neural differentiation of these cells, to the best of our knowledge, has not been reported. Low intensity pulsed ultrasound (LIPUS) has been reported to enhance cell differentiation. The aims of this study were (1) to explore the potential neural differentiation of HGPCs and (2) to investigate the effect of LIPUS on the differentiation of HGPCs when incubated under neuroinductive conditions. The HGPCs were isolated from human interdental papilla proximal to the premolar teeth that were extracted for orthodontic purpose. The HGPCs were induced to differentiate into neural lineage using a neuroinductive culture medium. HGPCs were divided into four groups; control group, neuro-induction (NI) group, ultrasound group (LIPUS), and a combined NI+LIPUS group. HGPCs were harvested for immunostaining and q-PCR after 1 day. Immunostaining for neuron specific antigens and q-PCR suggested that HGPCs can be differentiated into neural lineage and that selected neurodifferentiation markers can be enhanced by LIPUS. 相似文献
6.
Characterization of MADS-domain transcription factor complexes in Arabidopsis flower development 总被引:3,自引:0,他引:3
7.
Opolski MP Kepka C Achenbach S Juraszynski Z Pregowski J Kruk M Niewada M Jakubczyk M Teresinska A Chojnowska L Bilinska ZT Dzielinska Z Demkow M Ruzyllo W Chmielak Z Witkowski A 《The American journal of cardiology》2012,109(12):1722-1728
Conventional coronary angiography (CCA) has considerable limitations regarding visualization of distal vessel segments in chronic total occlusion. We assessed the ability of coronary computed tomographic angiography (CCTA) to predict the success of coronary artery bypass grafting (CABG) to the chronically occluded left anterior descending coronary artery (LAD) incompletely visualized on CCA. Thirty symptomatic patients rejected for CABG on the basis of the CCA findings underwent preoperative CCTA before intended transmyocardial laser revascularization. The LAD was explored operatively in all patients, and CABG to the LAD was attempted if the distal vessel was suitable for anastomosis. The procedural outcome of CABG and the 6-month patency of the left internal mammary artery graft at follow-up CCTA were defined as the primary and secondary end point, respectively. The primary and secondary end points were achieved in 80% and 77% of patients, respectively. We found a significant correlation between the intraoperative and computed tomographic measurement of distal LAD diameter (R = 0.428, p = 0.037). On multivariate analysis, the maximum diameter of the distal LAD by CCTA (odds ratio 8.16, p = 0.043) was the only independent correlate of procedural success of CABG. A cutoff value of 1.5 mm for the mean distal LAD diameter predicted left internal mammary artery graft patency with 100% specificity and 83% sensitivity. Successful CABG resulted in significant improvements in angina class and left ventricular function in LAD segments at 6 months of follow-up. In conclusion, CCTA predicted both the procedural and the intermediate outcome of CABG to chronic LAD occlusion with failed visualization on CCA. 相似文献
8.
Pregowski J Kaczmarska E Kepka C Kruk M Dzielinska Z Demkow M Witkowski A 《Journal of thoracic imaging》2012,27(3):W44-W45
A 23-year-old woman with an initial diagnosis of dilated cardiomyopathy for several years was referred to our center because of progressive congestive heart failure. Echocardiography showed a hypokinetic dilated left ventricle with globally impaired systolic function and an ejection fraction of 30%. We performed multislice cardiac computed tomography that revealed abnormal origin of the single coronary artery from the pulmonary trunk, lack of coronary arteries arising from the aorta, and abundant collateral flow from the bronchial artery to the anomalous coronary artery. This case report shows that cardiac computed tomography can be a valuable tool in the diagnosis of rare coronary anomalies. 相似文献
9.
Franek A Kostur R Polak A Taradaj J Szlachta Z Blaszczak E Dolibog P Dolibog P Koczy B Kucio C 《Ostomy/wound management》2012,58(3):30-44
The use of electrical stimulation has been studied in a variety of wounds emphasizing different variables with regard to provision of therapy. The purpose of this prospective, randomized, controlled clinical study was to evaluate the effect of high-voltage electrical stimulation (HVES) on nonhealing, lower-extremity, Stage II and Stage III pressure ulcers. Patients admitted for care and eligible to participate in the study received standard supportive care and topical treatments covered with wet-to-moist dressings. Patients assigned to the treatment arm of the study also received HVES (100 V; 100 μs; 100 Hz) continuously for 50 minutes once daily, five times per week. Patients were followed until healing for a maximum of 6 weeks. Wound tracings and measurements were obtained weekly. Over a 4-year period, 26 patients were enrolled in the treatment and 24 in the control group. Ulcers had existed for an average of 3.17 and 2.83 months in the treatment and control groups, respectively. Most were classified as Stage II (17 in the treatment and 16 in the control group) with an average baseline size of 4.54 cm2 and 3.97 cm2, respectively. Wound areas and linear measurements decreased significantly in both groups (P <0.05), but increases in granulation tissue were significant in the treatment group only (P = 0.006). Wound area, linear measurement, wound volume, and granulation tissue changes were statistically significantly greater in the treatment than in the control group starting in the second week of treatment. Week 6 surface area change was 88.9% (SD 14) in the treatment and 44.4% (SD 63.1) in the control group (P = 0.00003). Correlation coefficients between changes in wound surface area, longest length, and longest width were R = 0.96 and R = 0.98 in the treatment and R = 0.94 and R = 0.89 in the control group. HVES improved the healing rate of recalcitrant Stage II and Stage III pressure ulcers. Research to compare the effectiveness of using cathodic and anodal stimulation combined or alone and to determine the optimal duration of these two types of electrical stimulation is warranted. 相似文献
10.
The introduction of novel anti-angiogenic therapies has greatly improved the outcome of patients with metastatic renal cell carcinoma (mRCC). The use of these therapies in combination or sequentially is proposed to provide greater efficacy. We have reviewed completed and ongoing clinical trials in mRCC that have reported efficacy and/or safety data of novel therapies used in combination or sequentially. Bevacizumab appears to be a useful partner when combined with interferon (IFN), while controversial results have been reported when combined with temsirolimus and everolimus. Other combinations appear to have unacceptable tolerability or require dose or schedule optimization. Sequencing data provide a clear indication that multiple lines of treatment may extend survival. The 'ideal' sequence, however, is still unknown. In conclusion, novel therapies used in combination or sequentially have potential to provide optimised treatment and patient outcomes in mRCC. The results from ongoing/planned trials are expected to help shape future therapy. 相似文献