1.A Study on Apoptosis of HGPRT- Mouse Myeloma Cell Induced by Aminopterin, a de novo Pathway Blocking Agent.
Korean Journal of Immunology 1999;21(1):25-34
Programmed cell death (PCD), or apoptosis, plays an important role in embryonic development, metamorphsis, hormone-dependent atrophy and tumor growth, as a physiological event regulating the cell number or eliminating damaged cells. Currently hybridoma cell production, resulting from the fusion of myeloma cells with antibody producing spleen cells, is widely used in various fields of life science. This technique requires a hypoxanthine guanine phosphoribosyl transferase (HGPRT) deficient mutant myeloma cell line as a fusion partner. When these rnutant cells are treated with aminopterin plus hypoxanthine-thymidine (HAT) after the cell fusion they are selectively and efficiently eliminated so that one could get only fused hybridoma cells. But there hasn't been any report regarding this selective elimination mechanism of HGPRT mutant myeloma cell. By using HGPRT myeloma V653 as a model system this study demonstrated that PCD was induced by aminopterin treatment of this V653 cell. And this PCD was further characterized by cotreatement of cycloheximide, actinomycin-D, and calcium ionophore A23187 together with aminopterin. The apoptotic endonuclease involved in this PCD process was also detected and characterized. When V653 cells were incubated for the various periods of time in the presence of 0.4 uM aminopterin, the viability was continued to decrease until 48 hours of aminopterin treatment and there was no viable cell affer 36 hours of incubation. DNA fragmentation was detectable 3 hours of incubation and peaked between 12 and 18 hours of aminopterin treatment. The induction of cell death and DNA fragmentation of V653 cells by aminopterin were inhibited by protein synthesis inhibitor, cycloheximide, and RNA synthesis inhibitor, actinomycin-D and maximal inhibitory effects on cell death were seen at concentrations of 2 ug/ml and 0.5 uM, respectively. Ca2+ ionophore A23187 promoted aminopterin-induced cell death of V653. When the cells were coincubated with A23187 in the presence of aminopterin, cell viability was remarkably decreased at concentrations of more than 2 uM and DNA fragmentation was increased at concentrations of more than 0.2 uM. A23187 also induced cell death when the cells were treated with A23187 alone. When endogenous endonuclease activities of nuclei isolated from intact healthy cells and aminopterin-treated cells were compared for four different conditions, there were notable increases in the Ca2+/Mg2+ -independent and the Mg2+ -dependent endonuclease activity after incubation with aminopterin for 12 hours. In northern blot analysis, induction of c-myc gene was observed in aminopterin-treated V653 cell reached peak at 2 hours and thern decreased drastically.
Aminopterin*
;
Animals
;
Apoptosis*
;
Atrophy
;
Biological Science Disciplines
;
Blotting, Northern
;
Calcimycin
;
Calcium
;
Cell Count
;
Cell Death
;
Cell Fusion
;
Cell Line
;
Cell Survival
;
Cycloheximide
;
DNA Fragmentation
;
Embryonic Development
;
Female
;
Genes, myc
;
Guanine
;
Hybridomas
;
Hypoxanthine
;
Hypoxanthine Phosphoribosyltransferase
;
Mice*
;
Pregnancy
;
RNA
;
Spleen
;
Transferases
2.Clinical results of anterior repositioning splint
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 1993;15(2):113-122
No abstract available.
Splints
3.Electron Microscopic Analysis of Apoptosis of HGPRT- Mouse Myeloma Cell Induced by Aminopterin, a de novo Pathway Blocking Agent.
Yong CHOI ; Yong Hoon CHUNG ; Yang Ja CHO ; Yong Keel CHOI
Korean Journal of Immunology 1998;20(4):389-396
Programrned cell death (PCD), or apoptosis, is a process by which cells die in response to specific physiological and toxicological signals. This genetically programmed form of cellular suicide is intirnately involved in many biological processes including growth, metamorphosis, embryogenesis, and oncogenesis. Cells undergoing PCD in normal and neoplasmic tissues display the following biochemical and morphological features: internucleosomal DNA fragmentation, reduced cell volume, condensed chromatin in nucleus, zeiosis and generation of apoptotic bodies containing intact organelles and plasma rnembrane. Hybridoma cell production, resulting from the fusion of myeloma cells with antibody producing spleen cells, is widely used in various fields of life science. This technique requires hypoxanthine guanine phosphoribosyl transferase (HGPRT) deficient mutant myeloma cell line as a fusion partner. When these mutants cell is treated with aminopterin plus hypoxanthine-thymidine (HAT) after the cell fusion they are selectively and efficiently eliminated remaining fused hybridoma celis. But there hasn't been any report regarding the selective elimination mechanism of this HGPRT mutant myeloma cell. By using HGPRT myeloma P3-X 63-Ag8.653 (V653) as a model system, this study demonstrated that PCD was induced by aminopterin treatment of this V653 cell line. And the sequential ultrastructural changes during this death process were observed by using electron microscope. When V653 cells were incubated with 0.4 uM aminopterin, DNA fragmentation was detectable after 3 hours and peaked between 12 and 18 hours of aminopterin treatment and the cell viability decreased in a time dependant manner. V653 cells incubated with amiopterin showed following ultrastructural changes during the death process. Dilatation of rough endoplasmic reticulum (RER) and detachment of ribosomes were the earliest ultrastructural changes and first seen after 30 minute incubation. Dilatation of perinuclear cisternae began to appear after 1 hour and deformation of nucleoplasm such as decreased electron density of perinuclear heterochromatin and increased electron density of euchromatin were seen after 3 hours. Increased electron density of cytoplasm, decreased cell volume, condensation of chromatin and apoptotic bodies were observed in many cells after 9 hours but vacuolation by severe dilatation of RER was seen in some cells. 24 hours after incubation with aminopterin, many cells showed typical form of apoptosis characterized by cell shrinkage, increased electron density of cytoplasm and apoptotic bodies. On the contrary, some cells showed different type of cell death characterized by increased cell volume, decreased electron density of cytoplasm, severely dilated RER and apoptotic bodies. In both types of cells, mitochondrial cristae and limiting membrane of mitochondria are comparatively well preserved. In other cells, nuclei did not show significant changes but there were deformations of mitochondria such as markedly increased electron density and formation of lamella bodies. The death process of V653 cell was not synchronized among cells. The results of this study proved that aminopterin-induced selective elimination of fusion partner V653 myeloma cell is due to PCD. The earliest ultrastructural changes observed in this process were dilatation of RER and detachment of ribosomes. And there were two distinct morphological types in the PCD.
Aminopterin*
;
Animals
;
Apoptosis*
;
Biological Processes
;
Biological Science Disciplines
;
Carcinogenesis
;
Cell Death
;
Cell Fusion
;
Cell Line
;
Cell Size
;
Cell Survival
;
Chromatin
;
Cytoplasm
;
Dilatation
;
DNA Fragmentation
;
Embryonic Development
;
Endoplasmic Reticulum, Rough
;
Euchromatin
;
Female
;
Guanine
;
Heterochromatin
;
Hybridomas
;
Hypoxanthine
;
Hypoxanthine Phosphoribosyltransferase
;
Membranes
;
Mice*
;
Mitochondria
;
Organelles
;
Plasma
;
Pregnancy
;
Ribosomes
;
Spleen
;
Suicide
;
Transferases
4.A Case of Extramammary Paget's Disease.
Yong Myo PARK ; Dong Hoon SHIN ; Jong Soo CHOI
Yeungnam University Journal of Medicine 1989;6(2):265-269
Extramammary paget's disease is uncommon intraepithelial carcinoma of the skin and frequently associated with a subjacent or a regionally proximate carcinoma. We have experienced a case of extramammary Paget's disease affecting 71 year-old man. The patient has been suffered from a well demarcated, and slowly growing erythematous plaque on the left suprapubic area of 3 years. A biopsy specimen reveals infiltration of typical Paget's cells within the epidermis and the adnexa. We review the literature briefly.
Biopsy
;
Carcinoma in Situ
;
Epidermis
;
Humans
;
Paget Disease, Extramammary*
;
Skin
5.Heparin Therapy for Disseminated Intravascular Coagulation in Childhood.
Byung Ryul CHOI ; Yong Hoon PARK ; Jeong Ok HAH
Journal of the Korean Pediatric Society 1987;30(6):658-663
No abstract available.
Disseminated Intravascular Coagulation*
;
Heparin*
6.Anatomical Locking Plate with Additional K-wire Fixation for Distal Clavicle Fracture.
Woo Dong NAM ; Sung Hoon MOON ; Ki Yong CHOI
Clinics in Shoulder and Elbow 2017;20(4):230-235
BACKGROUND: Neer type II distal clavicle fractures have the drawback of coracoclavicular instability and insufficient distal bony fragment, thereby making it difficult to achieve adequate fixation. Although various surgical treatments have been described for Neer type II fracture, the optimal treatment remains controversial. This study reports the clinical results and usefulness of anatomical locking plate with additional K-wire fixation. METHODS: A totally of 21 patients with type II distal clavicle fracture were included in the study. The surgical procedure reduced the fracture temporarily; it included insertion of one or two K-wire from the lateral margin of the distal fragment to the proximal fragment through the fracture site, followed by application and fixation of the locking plate. The bony union and migration of K-wire was evaluated in the follow-up radiography. The coracoclavicular distance and acromioclavicular joint arthrosis were assessed at the final follow-up. The Constant Score (CS) and Korean Shoulder Score (KSS) were evaluated for clinical scoring. RESULTS: Bone union was achieved in all cases. At the final follow-up, coracoclavicular distance of the injured shoulder was increased, as compared to the intact shoulder (p=0.002), with no accompanying clinical symptoms. No K-wire migration was observed. At the final follow-up, K-wire irritation was observed in two cases and acromioclavicular arthrosis in one case, with no other adverse effects. Pain visual analogue scale, CS, and KSS were improved in all cases. CONCLUSIONS: The method of anatomical locking plate with additional K-wire fixation could be useful in achieving beneficial clinical results.
Acromioclavicular Joint
;
Clavicle*
;
Follow-Up Studies
;
Humans
;
Methods
;
Radiography
;
Shoulder
7.THE EffECT OF THE 5-FLUOROURACIL ON THE HAIR OF RAT: SCANNING ELECTRONMICROSCOPIC STUDY
Yong Chul CHOI ; Kyung Wook KIM ; Jae Hoon LEE
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 1998;20(2):158-165
Animals
;
Body Weight
;
Fluorouracil
;
Hair
;
Rats
;
Rats, Sprague-Dawley
8.Effective Inhibition of Glomerulosclerosis by Adenoviral Vector Expressing Human IL-10.
Young Kook CHOI ; Yong Jin KIM ; Yong Hoon PARK ; Kyu Sam CHOI ; Jong Gu PARK
Korean Journal of Immunology 2000;22(3):187-195
No abstract available.
Humans*
;
Interleukin-10*
9.Development of Monoclonal Antibodies Recognizing Human Peripheral Blood T Lymphocytes Cytoplasmic Proteins Induced upon Activation.
Yang Ja CHO ; Yong Hoon CHUNG ; Yong CHOI ; Yong Sik KIM
Korean Journal of Immunology 1997;19(1):145-156
Antigen-specific T cell activation requires interaction of the T cell with specialized antigen-presenting cells. Signaling through the TCR is necessary but not sufficient to induce antigen-specific T cell activation and cytokine secretion. This first signal, termed signal 1, is both antigen-specific and MHC-restricted. Signal 2, which is neither antigen-specific nor MHC-restricted, is necessary to induce cytokine secretion, cellular proliferation, and effector function. Recently immunological studies in T cell activation area are mainly focused on biological and molecular biological characterization of TCR/CD3 complex and accessary molecules providing costimulatory signal (signal 2). If signal 2 is not delivered, T cell enter a state of long term un-responsiveness to specific antigen-termed anergy. Monoclonal antibody technique has been especially involved in recognizing novel inducible cell surface antigens on T cell activation. This study was aimed to develop monoclonal antibodies recognizing novel cytoplasmic proteins present in activated T cells. We make 6 monoclones involved in changing pattern of T cell activated cytoplasmic proteins. Using these 6 monoclonal antibodies analyze to find novel molecules involved in T cell activation associated response, apoptosis, and/or heat shock response of the T cells in early T cell activation.
Antibodies, Monoclonal*
;
Antigen-Presenting Cells
;
Antigens, Surface
;
Apoptosis
;
Cell Proliferation
;
Cytoplasm*
;
Heat-Shock Proteins
;
Heat-Shock Response
;
Humans*
;
T-Lymphocytes*