1.The effects of gamma-radiation on cyclin-dependent kinases and their inhibitors in cultured vascular smooth muscle cells.
Korean Circulation Journal 2001;31(1):63-73
BACKGROUND: In spite of the clinical introduction of brachytherapy to reduce restenosis, the biologic responses of vascular smooth muscle cells(VSMCs) to radiation have not been well studied. We investigated the effects and mechanisms of gamma-irradiation on the cell cycle of VSMCs using primary cultures of rat aortic VSMCs and 137Cs as a radiation source. METHODS & RESULTS: The cell counts after irradiation with 0, 2, 8, 16 Gray (Gy) (n=, each) were 3.28, 2.34, 1.94 and 1.30 x 105/ml at 24h, and 5.10, 2.00, 1.80 and 1.20 x 105/ml at 48h, respectively. The proportions of cells in the G0/G1, S and G2/M phases, as measured by Fluorescence Activated Cell Sorter, were 61, 9 and 30% at 12 hours after 16Gy radiation (control 61, 34 and 5%), 65, 9 and 26% at 24 hours (control 70, 16 and 14%); and 67, 7 and 26% (control 78, 12 and 10%) at 48 hours, which demonstrated G1 and G2 arrest. By immunoblot analysis and kinase assay, gamma-irradiation with 8 or 16 Gy increased the expression of p21, universal cell cycle inhibitor, and decreased the expression and activity of CDK2, an important kinase during the later stages of G1/S progression, as well as the expression and activity of CDK1, which is important in the G2/M phase transition. In contrast, radiation did not affect the expression or activity of either CDK4 or CDK6. The cell-cycle inhibitors, p27 and p16 were not involved in the radiation-induced cell cycle arrest of VSMCs. CONCLUSION: Gamma-irradiation can effectively inhibit VSMC proliferation because it causes cell cycle arrest at both the G1 phase by enhancing P21 expression and suppressing CDK2, and at the G2/M phase by suppressing CDK1.
Animals
;
Brachytherapy
;
Cell Count
;
Cell Cycle
;
Cell Cycle Checkpoints
;
Cyclin-Dependent Kinases*
;
Fluorescence
;
G1 Phase
;
Muscle, Smooth, Vascular*
;
Phase Transition
;
Phosphotransferases
;
Rats
3.Extraskeletal osteogenic sarcoma of the mediastinum: 1 case report.
The Korean Journal of Thoracic and Cardiovascular Surgery 1993;26(5):413-416
No abstract available.
Mediastinum*
;
Osteosarcoma*
5.Current Status, Prevention and Control Strategy of Vancomycin-resistant Enterococci (VRE) in Korea.
Korean Journal of Nosocomial Infection Control 1998;3(1):57-64
No Abstract available.
Korea*
6.A Study on Periphral T Cell Subsets in Asymptomatic HBsAg Carriers and Children with Chronic Hepatitis B and Hepatitis B vaccine Inoculated Infants.
Journal of the Korean Pediatric Society 1989;32(9):1248-1258
No abstract available.
Child*
;
Hepatitis B Surface Antigens*
;
Hepatitis B Vaccines*
;
Hepatitis B*
;
Hepatitis B, Chronic*
;
Hepatitis*
;
Hepatitis, Chronic*
;
Humans
;
Infant*
;
T-Lymphocyte Subsets*
7.Clinical Studies on Congenital Anomalies.
Hyeon Joo CHAI ; Kyung Hee KIM
Journal of the Korean Pediatric Society 1990;33(6):754-761
No abstract available.
8.Detection of tubular proteinuria using gradient gel SDS-PAGE.
Korean Journal of Clinical Pathology 1991;11(3):529-536
No abstract available.
Electrophoresis, Polyacrylamide Gel*
;
Proteinuria*
9.The early surgical treatment of congenital muscular torticollis in infancy.
Journal of the Korean Surgical Society 1991;41(2):247-253
No abstract available.
Torticollis*
10.Endothelium-Dependent Vasodilation Responses in the Patients with Congestive Heart Failure.
Korean Circulation Journal 1998;28(10):1755-1759
BACKGROUND: Many studies reported that endothelium-dependent vasodilator response is impaired in patients with congestive heart failure. But the opposite results also were reported. The aim of this study was to determine the presence of endothelial dysfunction and its characteristics. METHODS AND MATERIALS: Forearm blood flow was measured in 12 patients with congestvie heart failure (7 males and 5 females, mean age 53+/-11 years old) and 10 normal control subjects (5 males and 5 females, mean age 41+/-10 years old) using strain-gauge plethysmography. The endothelium-dependent vasodilators were acetylcholine (7.5, 15, and 30 microgram/min), which uses a pertussis toxin-sensitive signal transduction pathway, and bradykinin (100, 200, and 400 ng/min), which uses a pertussis toxin-insensitive signal transduction pathway to activate nitric oxide production. Sodium nitroprusside (0.8, 1.6, and 3.2 microgram/min) was used as an endothelium-independent vasodilator. All drugs were infused into the brachial artery with random order. RESULTS: The basal forearm blood flow was similar between both groups. The maximum flow in response to acetylcholine, bradykinin, and sodium nitroprusside was also similar in two groups. CONCLUSIONS: Patients with congestive heart failure showed normal endothelium-dependent vasodilator responses to both acetylcholine and to bradykinin. This finding indicates that the endothelial vasodilator function is normal in the patients with heart failure.
Acetylcholine
;
Brachial Artery
;
Bradykinin
;
Endothelium
;
Endothelium-Dependent Relaxing Factors
;
Estrogens, Conjugated (USP)*
;
Female
;
Forearm
;
Heart Failure*
;
Humans
;
Male
;
Nitric Oxide
;
Nitroprusside
;
Plethysmography
;
Signal Transduction
;
Vasodilation*
;
Whooping Cough
Result Analysis
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