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91.
Kim MS Seo KS Seong HS Cho SH Lee HB Hong KD Kim SK Khang G 《Bio-medical materials and engineering》2005,15(3):229-238
p-Carboxyphenoxy propane (CPP) prepolymer consisting of 4 units and sebacic acid (SA) prepolymer consisting of about 10 units were synthesized by reacting CPP and SA in the presence of excess acetic anhydride, respectively. Polyanhydride, poly(CPP-SA) copolymers were copolymerized by a melt polycondensation process with a mixture of CPP and SA prepolymer. Copolymers of average molecular weight up to 110,000 g/mol were achieved. The crystallinity of poly(CPP-SA) copolymers was decreased by the addition of the CPP homopolymer segment to SA homopolymer. Poly(CPP-SA) copolymers gradually degraded for period of 10 days. No large difference of weight loss observed according to molecular weight variation of poly(CPP-SA) copolymers. BCNU release from wafers fabricated by poly(CPP-SA) showed a sustained release pattern with no initial burst and delay of drug release. 相似文献
92.
The predominant enzymes responsible for elimination of hydrogen peroxide (H(2)O(2)) in cells are peroxiredoxins (Prxs), catalase, and glutathione peroxidases (GPxs). Evidence suggests that catalytic activities of certain isoforms of these H(2)O(2)-eliminating enzymes are extensively regulated via posttranslational modification. Prx I and Prx II become inactivated when phosphorylated on Thr(90) by cyclin B-dependent kinase Cdc2. In addition, the active-site cysteine of Prx I-IV undergoes a reversible sulfinylation (oxidation to cysteine sulfinic acid) in cells. Desulfinylation (reduction to cysteine) is achieved by a novel enzyme named sulfiredoxin. c-Abl and Arg nonreceptor protein tyrosine kinases associate with catalase in cells treated with H(2)O(2) by mechanisms involving the SH3 domains of the kinases and the Pro(293)PheAsnPro motif of catalase and activate catalase by phosphorylating it on Tyr(231) and Tyr(386). Similarily, GPx1 is activated by c-Abl- and Arg-mediated phosphorylation. The tyrosine phosphorylation is critical for ubiquitination-dependent degradation of catalase. 相似文献
93.
This study was performed to investigate the effects of behavior modification on body image, depression and body fat in obese elementary school children. Sixty-two elementary students of the 4th to 6th grade were selected from two different Seoul schools. Thirty-four children in one school were designated as the experimental group, and 28 children from the other school as the control group. The experimental group received 60 - 70 minutes of behavior modification, once a week, for 8 weeks. The control group received neither management nor treatment. The results indicated a significant improvement of body image and a reduction in the increase rate of body fat for the experimental group. This finding strongly supports the theory that behavior modification can be used as an effective strategy in the treatment of obese children. 相似文献
94.
Associations of serum TRAIL concentrations, anthropometric variables, and serum lipid parameters in healthy adults 总被引:1,自引:0,他引:1
To investigate the relationships of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), anthropometric variables, and lipid parameters, we measured serum TRAIL concentrations, body mass index (BMI), total body fat (TBF), and serum lipid profiles in 207 healthy adults. There were no significant differences in serum TRAIL concentrations between men and women, nor between elderly persons and middle-aged subjects. However, men with TBF 16.4 kg (75th per centile) exhibited significantly higher serum TRAIL concentrations than those with TBF 11.2 kg (25th per centile) (69.7 +/- 15.1 pg/ml vs 50.2 +/- 14.3 pg/ml, p < 0.05). Serum TRAIL concentration averaged 76.2 +/- 16.1 pg/ml in women with low-density lipoprotein cholesterol (LDL-C) 165 mg/dl (75th per centile), which was significantly above the values (53.1 +/- 12.9 pg/ml, p < 0.05) in those with LDL-C 117 mg/dl (25th per centile), although no differences were observed on the basis of TBF (75th percentile vs 25th percentile). Serum TRAIL concentrations correlated significantlywithTBF (r = 0.31, p < 0.05) and lean body mass (r = -0.26, p <0.05) in men and LDL-C (r = 0.32, p < 0.05) and total cholesterol (r = 0.21, p < 0.05) in women. In conclusion, serum TRAIL concentrations are associated with serum lipid levels and body adiposity in healthy adults, but are unrelated to a subject's age or gender. 相似文献
95.
This study was performed to investigate the effect of peritoneal glucose load on plasma leptin concentrations in the continuous ambulatory peritoneal dialysis (CAPD) performed on 13 non-diabetic ESRD patients. Plasma leptin and insulin concentrations were measured for 2 hours during a single 2 liter exchange of 1.5% glucose-based dialysate (SPD, n = 6), for 7 days of daily peritoneal dialysis (DPD, n = 7). In DPD, standard full volume (2,000 ml x 4 times/day) exchange was performed immediately after operation. In SPD, plasma leptin and insulin concentrations remained unchanged during the study. In DPD, the plasma leptin concentration increased significantly after CAPD on the first day (PD1) (11.2 +/- 5.4 to 17.0 +/- 6.0 ng/mL, p < 0.05) and this elevation seemed to persist until 7 days after operation. After CAPD, there was no significant day-to-day variation in peritoneal glucose absorption (391-465 cal). Oral intake seemed to decrease on operation day (PD0) and PD1 and then increased slowly. Plasma insulin and glucose concentrations did not significantly change after CAPD. Changes of leptin concentration were significantly correlated with the changes of peritoneal glucose absorption at PD1. In conclusion, continuous peritoneal glucose load may affect plasma leptin concentrations in CAPD patients. 相似文献
96.
We explore the pursuit in a plane of a target moving at constant slow speed in a straight line. Two models of the pursuit are given. In the continuous case, the pursuer is moving at constant speed and is subject to proportionate angular homeostasis with correction constant b. In the discrete version movement occurs at a constant speed in a sequence of straight line segments of constant length (called the step size, s) the end of the segments being called the vertices. The pattern considered is not the absolute position of the pursuer, but its distance and orientation relative to the target. Both the transients and the asymptotic orbit are addressed. A key quantity is r, the speed of the target expressed as a fraction of that of the pursuer. If the speed of the pursuer is defined as unity, r is also the ratio of the speeds. There exists a critical speed fraction, R(b,s), a function of b and s, that defines what the term slow designates. R(b,s), which has to be found numerically, has the following property. For r less than R(b,s), the asymptotic path is a simple closed curve. In the discrete case the vertices converge to a simple closed curve. The larger r, the more the path (or in the discrete analogue its set of vertices) departs from a circle, and the more eccentric the target is with respect to it. Interest centers on two issues. First we address the transient patterns of the path, notably whether or not the sense of any particular path (clockwise or counterclockwise) is the same throughout, or changes at some stage.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
97.
98.
Implantation of bone marrow mononuclear cells using injectable fibrin matrix enhances neovascularization in infarcted myocardium 总被引:11,自引:0,他引:11
Ryu JH Kim IK Cho SW Cho MC Hwang KK Piao H Piao S Lim SH Hong YS Choi CY Yoo KJ Kim BS 《Biomaterials》2005,26(3):319-326
Neovascularization may improve cardiac function and prevent further scar tissue formation in infarcted myocardium. A number of studies have demonstrated that bone marrow-derived cells have the potential to induce neovascularization in ischemic tissues. In this study, we hypothesized that implantation of bone marrow mononuclear cells (BMMNCs) using injectable fibrin matrix further enhances neovascularization in infarcted myocardium compared to BMMNC implantation without matrix. To test this hypothesis, infarction was induced in rat myocardium by cryoinjury. Three weeks later, rat BMMNCs were mixed with fibrin matrix and injected into the infarcted myocardium. Injection of either BMMNCs or medium alone into infarcted myocardium served as controls. Eight weeks after the treatments, histological analyses indicated that implantation of BMMNCs using fibrin matrix resulted in more extensive tissue regeneration in the infarcted myocardium compared to BMMNC implantation without matrix. Examination with fluorescence microscopy revealed that cells labeled with a fluorescent dye prior to implantation survived in the infarcted myocardium at 8 weeks of implantation. Importantly, implantation of BMMNCs using fibrin matrix resulted in much more extensive neovascularization in infarcted myocardium than BMMNC implantation without matrix. The microvessel density in infarcted myocardium was significantly higher (p < 0.05) when BMMNCs were implanted using fibrin matrix (350 +/- 22 microvessels/mm2) compared to BMMNC implantation without matrix (262 +/- 13 microvessels/mm2) and medium injection (76 +/- 9 microvessels/mm2). In addition, average internal diameter of microvessels was significantly larger (p < 0.05) in BMMNC implantation with fibrin matrix group (14.6 +/- 1.2 microm) than BMMNC implantation without matrix group (10.2 +/- 0.7 microm) and medium injection group (7.3 +/- 0.5 microm). These results suggest that fibrin matrix could serve as a cell implantation matrix that enhances neovascularization efficacy for myocardial infarction treatment. 相似文献
99.
Immunohistochemical analysis of Smac/DIABLO expression in human carcinomas and sarcomas 总被引:27,自引:0,他引:27
Yoo NJ Kim HS Kim SY Park WS Park CH Jeon H Jung ES Lee JY Lee SH 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(3):382-388
Second mitochondria-derived activator of caspases (Smac/DIABLO) is released from mitochondria into the cytosol during apoptosis, promoting caspase activation by neutralizing the inhibition of inhibitor of apoptosis proteins (IAPs) on caspases. Alteration of apoptosis is essential for cancer development, and cancer cell death by radiation and chemotherapy is largely dependent upon apoptosis. In this study, archival tissues of 100 carcinomas and 50 sarcomas from various origins were analyzed by immunohistochemistry for the expression of Smac/DIABLO. Smac/DIABLO immunoreactivity was seen in 62 of 100 (62%) carcinomas, including 42 of 60 stomach carcinomas, 7 of 10 colorectal carcinomas, 4 of 10 lung carcinomas, 7 of 10 ovarian carcinomas, and 2 of 10 prostate carcinomas. Smac/DIABLO is expressed in 11 of 50 (22%) sarcomas, including 2 of 8 malignant schwannomas, 5 of 11 rhabdomyosarcomas, 2 of 7 malignant fibrous histiocytomas, 1 of 6 leiomyosarcomas, 0 of 8 angiosarcomas, 0 of 8 liposarcomas, and 1 of 2 Ewing's sarcomas. These data demonstrated that Smac/DIABLO expression levels vary depending on the individual cancer types. Furthermore, the present study showed that many human cancers do not express Smac/DIABLO, and suggest that lack of Smac/DIABLO expression in the cancer cells may inhibit apoptosis, thereby promoting their survival. 相似文献
100.
Park SH Park KS Park HG Lee HJ Seo JK Lee KH Kim DH Lee WH Lee CW Hong MK Park SW Park SJ 《Journal of Korean medical science》2003,18(4):585-588
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy. 相似文献