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101.
Anticancer vaccination therapies with monocyte-derived dendritic cells (DC) are widely conducted. A large number of primary monocytes (approximately 108 cells) are needed to generate the number of DC required to achieve an effect upon vaccination, and monocytes are usually purified from peripheral blood mononuclear cells obtained by apheresis procedure, which is somehow invasive for cancer patients. As a means to facilitate the generation of DC for therapeutic use, we herein report a method to amplify human monocytes. We found that lentivirus-mediated transduction of cMYC along with BMI1 induced proliferation of CD14+ monocytes derived from 9 out of 12 blood donors, and we named the monocyte-derived proliferating cells CD14-ML. Their proliferation continued for 3–5 weeks in the presence of M-CSF and GM-CSF, resulting in 20–1000-fold amplification. Importantly, the expanded CD14-ML differentiated into fully functional DC (CD14-ML-DC) upon the addition of IL-4 to the culture. We successfully stimulated autologous CD8+ T cells with CD14-ML-DC pulsed with cytomegalovirus peptide or MART-1 peptide to generate antigen-specific CTL lines. This is the first report describing the method for in vitro expansion of human peripheral blood monocytes.  相似文献   
102.
Journal of Medical Ultrasonics - Ultrasound (US) is a cost-effective and noninvasive procedure without radiation exposure, with real-time evaluation and high spatial resolution. Although it is...  相似文献   
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In order to clarify the mechanism of the prevention of diabetes mellitus developing after subtotal pancreatectomy, we examined regenerative activities of islet B-cells in 90% pancreatectomized and poly (ADP-ribose) synthetase inhibitor-treated rats by using autoradiographic and stathmokinetic techniques. Thirty days after 90% pancreatectomy, islets of rats without 3-aminobenzamide treatment were decreased in number, small in size and had irregular contour. Degranulation of the B-cells and fibrotic degeneration were frequently encountered. On the contrary, islets of remaining pancreas in rats receiving 3-aminobenzamide were increased in number, and their diameters ranged from 0.3-0.6 mm, being about two fold larger than those of normal rats. The labeling index of 3H-thymidine autoradiography and the mitotic indices in islet B-cells were increased in a temporally correlated manner in the 3-aminobenzamide treated rats. The mitotic indices of the 3-aminobenzamide-treated group on the 5th, 7th, 10th and 15th days were significantly larger than those in the control group. These results indicate that poly (ADP-ribose) synthetase inhibitors can induce self-replication or regeneration of B-cells in partially pancreatectomized rats.  相似文献   
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Prolactin (PRL) secretion is regulated by photoperiod in mammals and birds. In mammals, the pars tuberalis (PT) in the pituitary is involved in the regulation of photoperiodic regulation of PRL secretion. In birds, however, hypothalamic vasoactive intestinal peptide is implicated in PRL secretion, and physiological roles of the avian PT remain unknown. In the present study, we show that PRL secretion increases under long days and short days with a night interruptive schedule, both of which also cause gonadal growth in Japanese quail. We have also found Cry1 gene expression in the PT of Japanese quail. Cry1 expression was rhythmic under long and short photoperiods in the PT, and the peak was phase delayed under a lengthened photoperiod. Moreover, expression of Cry1 gene was induced by a light pulse but only when given during the photoinducible phase. In our previous study, we have shown rhythmic Per2 gene expression with a peak in the PT during the early day under various photoperiods. When taken together with the results from the present study, different phase relationships between Per2 and Cry1 in the Japanese quail PT under different photoperiods may decode photoperiodic information and regulate photoperiodic PRL secretion in a manner similar to that of mammals.  相似文献   
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To clarify factors which have an influence on late potentials (LPs), signal averaged electrocardiogram, echocardiogram, cardiac catheterization and Holter monitoring were studied in 86 patients with previous myocardial infarction (MI). Group 1 consisted of 27 patients with LPs (LP duration greater than or equal to 20 msec) and Group 2 consisted of 59 patients without them. Twelve percent of anterior MI and 35% of inferior MI had LPs. Left ventricular (LV) diastolic dimension was larger and % fractional shortening was lower in group 1 than those in group 2. LV end-diastolic volume index and LV end-systolic volume index were larger and LV ejection fraction was lower in group 1 than those in group 2. Aneurysm was noted in 37% in group 1 and 17% in group 2 (p less than 0.05), and mean number of involved coronary vessels was 2.3 +/- 0.8 in group 1 and 1.7 +/- 0.8 in group 2 (p less than 0.05). No significant difference was found in other clinical and hemodynamic parameters. The incidence of patients with 100 or more ventricular premature contractions per hours and that with ventricular tachycardia (VT) were significantly higher in group 1 than in group 2 (26% vs 7%, p less than 0.05, 33% vs 7%, p less than 0.01, respectively). Multiple regression analysis and the method of quantification demonstrated that ventricular arrhythmia was most strongly associated with LP duration.  相似文献   
110.

Background

Cardiac fibrosis is considered to be a crucial factor in the development of heart failure. Blockade of the mineralocorticoid receptor (MR) attenuated cardiac fibrosis and improved the prognosis of patients with chronic heart failure but the ligand for MR and the regulatory mechanism of MR pathway in the diseased heart are unclear. Here, we investigated whether glucocorticoids can promote cardiac fibrosis through MR in oxidative stress and the involvement of elongation factor eleven-nineteen lysine-rich leukemia (ELL), a co-activator of MR, in this pathway.

Methods and Results

The MR antagonist eplerenone attenuated corticosterone-induced collagen synthesis assessed by [3H]proline incorporation in rat neonatal cultured cardiac fibroblasts in the presence of H2O2, as an oxidative stress but not in the absence of H2O2. H2O2 increased the ELL expression levels and MR-bound ELL. ELL expression levels and MR-bound ELL were also increased in the left ventricle of heart failure model rats with significant fibrosis and enhanced oxidative stress. Eplerenone did not attenuate corticosterone-induced increase of [3H]proline incorporation in the presence of H2O2 after knockdown of ELL expression using small interfering RNA in cardiac fibroblasts.

Conclusion

Glucocorticoids can promote cardiac fibrosis via MR in oxidative stress, and oxidative stress modulates MR response to glucocorticoids through the interaction with ELL. Preventing cardiac fibrosis by modulating glucocorticoid-MR-ELL pathway may become a new therapeutic strategy for heart failure.  相似文献   
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