No abstract available.
Animals* ; Brain* ; Hypothermia* ; In Situ Nick-End Labeling* ; Models, Animal*

This study evaluated the response of the anterior stromal keratocytes in Rabbits following deepithelialization and 3 diopter(37micrometer)- and 12 diopter(99micrometer) PRK. The corneal sections obtained from the operated area on postoperative 3, 7 and 14 days were stained with hematoxylin and eosin. Keratocyte apoptosis were monitored using the terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling(TUBEL) staining with ApopTag kit for the corneal section obtained on postoperative 3 day. The corneal haze on postoperative 14 day were graded using a slit lamp biomicroscopy. The number of anterior stromal keratocytes had decreased significantly and positive TUNEL staining was noted in the anterior stroma after PRK and deepithelialization campared with that of controls. The decreased keratocyte numbers were recovered on postoperative 7 day after deepithelialization and on postoperative 14 day after PRK. The newly appeared deratocytes were pyknotic, variable-shaped and crosswisely oriented in appearance, and especially increased following 12 diopter PRK. Both the keratocyte loss and corneal haze grading was increased related to the increased ablation depth after PRK. In conclusion, the loss of anterior stromal keratocytes after PRK is mediated by apoptosis and followed by reactive cellular proliferation might be a important role in the corneal haze.
Apoptosis ; Cell Proliferation ; Cornea* ; Eosine Yellowish-(YS) ; Hematoxylin ; In Situ Nick-End Labeling ; Photorefractive Keratectomy* ; Rabbits

PURPOSE: The purposes of this study were to examine whether meniscal degeneration in human osteoarthritis(OA) was related with the occurrence of apoptosis, the expression of nitrotyrosine and Fas. MATERIALS AND METHODS: Menisci were obtained from OA patients undergoing total knee replacement arthroplasty and from normal subjects who were operated an above knee amputaton. According to histologic degeneration, menisci were graded to normal, grade 1(mild), grade 2(moderate), and grade 3(severe). Apoptotic cells were identified by TUNEL method and electron microscopy. Meniscal sections were analyzed by immunohistochemistry for the presence of nitrotyrosine and Fas expression. RESULTS: The number of apoptotic cells were significantly increased in OA meniscus compared with normal meniscus(p < 0.05). The number of apoptotic cells were increased with tissue degeneration. On electron microscopy, the typical chromatin condensation in the OA meniscus was shown in apoptotic cell. The number of Fas-expressing cells was significantly higher in the OA meniscus(p < 0.05). Nitrotyrosine immuno reactivity was prominent in the degenerative menisci(p < 0.05). Fas and nitrotyrosine expression were increased with degree of tissue degeneration. An increase in number of apoptotic cells was correlated with tissue degeneration but not with age . CONCLUSION: Apoptosis was suggested as one of the causes in the tissue degeneration of the human OA meniscus. The development of apoptosis in the meniscus may be related with Fas and nitrotyrosine expression but not with age.
Apoptosis* ; Arthroplasty ; Arthroplasty, Replacement, Knee ; Chromatin ; Humans* ; Immunohistochemistry ; In Situ Nick-End Labeling ; Knee* ; Microscopy, Electron

PURPOSE: Replication-competent adenoviruses (Ads) are promising new modalities for the treatment of cancer. Selective replication of a viral agent in tumor may lead to improved efficacy over non-replicating Ads due to viral multiplication, lysis of the infected cancer cell and spread to surrounding cells. In our previous studies it was shown that the E1B 55 kD-deleted Ad (YKL-1) exhibits tumor specific replication and cell lysis, but with reduced cytolytic effects compared to the wild type adenovirus (Int J Cancer 2000;88: 454-463). Thus, improving the potency of oncolytic Ads remains an important goal for cancer gene therapy. To increase the oncolytic ability of YKL-1, an adenovirus death protein (ADP) gene was reintroduced under the control of a CMV or MLP promoter at the E3 region of the YKL-1, generating an YKL-cADP and YKL-mADP, respectively. MATERIALS AND METHODS: The in vitro cytolytic effect of ADP expressing Ads was evaluated by MTT assay, and the induction of apoptosis by ADP expressing Ads was examined by TUNEL analysis. Finally, the antitumor effect of ADP expressing Ads was demonstrated in C33A xenograft tumor model. RESULTS: The YKL-cADP exerted a markedly enhanced cytolytic effect against H460 and SK-Hep1 cancer cell lines. The TUNEL assay indicated that the ADP-mediated cytotoxicity was largely driven by apoptosis. Finally, the YKL-cADP showed a superior antitumor effect than the YKL-1 or YKL-mADP in C33A xenografts. CONCLUSION: These lines of evidence demonstrate that the YKL-cADP induces efficient cell lysis, which is critical for the addition of therapeutic value to replicating Ads in cancer gene therapy.
Adenosine Diphosphate ; Adenoviridae* ; Apoptosis ; Cell Line ; Genes, Neoplasm ; Heterografts ; In Situ Nick-End Labeling

We studied the mechanism and inhibition of cell death by exposure to UV alone or combination of UV exposure and intracellular zinc depletion with TPEN in cultured human retinal pigment epithelial cells (RPE). Cell death was quantified by measuring LDH release from injured cells. RPE were exposed to UV at 253.7 nm for 1~20 minutes.The 2~5 minutes UV exposure was duration-dependently cytotoxic, whereas 1minute exposure was minimally so.And exposure to TPEN induced concentration-dependent cell death at 1~4 micrometer range ;0.5 micrometer TPEN was minimally toxic.Then, cultures were exposed to varying exposure durations of UV in the absence or presence of 0.5 micrometer TPEN.At any point, the presence of TPEN markedly increased UV toxicity.In contrast, cell membrane-impermeable zinc chelator showed no toxicity.On the other hand, addition of a protein synthesis inhibitor or caspase inhibitor was markedly protective.In addition, RPE injury with exposure to combination of UV 1 min and TPEN 0.25 micrometer was accompanied by TUNEL and Hoechst staining positivity indicating that the toxicity is mainly apoptosis.Electron microscopic examinations revealed that nuclear fragmentation occurred even in sublethal UV or TPEN exposure, suggesting that the injury process already began at these condition consistently with the death being apoptosis. The present study has shown that combination of known risk factors may act synergistically to induce ARMD etc.The RPE injury induced by low dose UV and minimal intracellular zinc depletion was inhibited with protein synthesis inhibitor or caspase inhibitor, so these results suggested the possibility of prevention or treatment of RPE dysfunction.
Apoptosis ; Cell Death ; Epithelial Cells* ; Hand ; Humans* ; In Situ Nick-End Labeling ; Retinaldehyde* ; Risk Factors ; Zinc*

PURPOSE: Flavopiridol enhanced radiation-induced apoptosis of cancer cells in our previous in vitro study. The purpose of this study was to assess if flavopiridol could enhance the radioresponse of mouse mammary tumors in vivo. MATERIALS AND METHODS: Balb/c mice bearing EMT-6 murine mammary carcinoma were treated with flavopiridol only, radiation only, or both for 7 days. Flavopiridol was administered 2.5 mg/kg twice a day intraperitoneally (IP). Radiation was delivered at a 4 Gy/fraction at 24-h intervals for a total dose of 28 Gy. Tumor volume was measured and compared among the different treatment groups to evaluate the in vivo radiosensitizing effect of flavopiridol. Tumors were removed from the mice 20 days after treatment, and TUNEL and Immunohistochemical stainings were performed. RESULTS: Significant tumor growth delay was observed in the radiation only and combined treatment groups, when compared with the control group. However, there was no significant difference between the tumor growth curves of the control and flavopiridol only group or between the radiation only and combination treatment group. Apoptotic cells of different treatment groups were detected by terminal deoxynucleotidyl transferase-medicated nick end labeling (TUNEL) staining. The expressions of Ku70 in tumor tissues from the different groups were analyzed by immunohistochemistry. Similarly, no significant difference was found between the apoptotic rate or Ku70 expression among the different treatment groups. CONCLUSION: Flavopiridol did not show evidence of enhancing the radioresponse of mouse mammary tumors in this study.
Animals ; Apoptosis ; Flavonoids ; Immunohistochemistry ; In Situ Nick-End Labeling ; Mice ; Piperidines ; Radiation-Sensitizing Agents ; Tumor Burden ; Ursidae

The apoptotic effect of bacteria-derived beta-glucan was investigated in human colon cancer cells SNU-C4 using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, reverse transcription-polymerase chain reaction (RT-PCR) expressions of Bcl-2, Bax, and Caspase-3 genes, and assay of caspase-3 enzyme activity. beta-Glucan of 10, 50, and 100 microg/mL decreased cell viability in a dose-dependent manner with typical apoptotic characteristics, such as morphological changes of chromatin condensation and apoptotic body formation from TUNEL assay. In addition, beta-glucan (100 microgram/mL) decreased the expression of Bcl-2 by 0.6 times, whereas the expression of Bax and Caspase-3 were increased by 3.1 and 2.3 times, respectively, compared to untreated control group. Furthermore, the caspase-3 activity in the beta-glucan-treated group was significantly increased compared to those in control group (P < 0.05). Bacterial derived beta-glucan could be used as an effective compound inducing apoptosis in human colon cancer.
Apoptosis ; Caspase 3 ; Cell Survival ; Chromatin ; Colon ; Colonic Neoplasms ; DNA Nucleotidylexotransferase ; Humans ; In Situ Nick-End Labeling

OBJECTIVE: This study is designed to investigate how apoptosis is presented and how the genes of p53 and bcl-2 are expressed depending on graded injury in experimental spinal cord injury. METHODS: Experimental spinal cord injury was made on rats with weight drop method. Two different amounts of impact were applied on rat spinal cord. Rats were categorized into three groups (control; five rats, mild injury; five rats, severe injury; five rats). Fourty eight hours following cord injury, cord specimen was harvested from injury epicenter. TUNEL staining was done for apoptotic detection and immunohistochemical staining for p53 and bcl-2 expression. Positively stained cells were counted and mean values were compared among three groups. RESULTS: TUNEL positive cells increased depending on injury severity(p=0.027). The p53 positive cells increased in both injury groups compared to control group(p=0.001). Bcl-2 positive cells decreased as injury amount increased(p=0.002). The p53 expression increased in proportion to TUNEL staining in correlation curve in white matter(correlation coefficient, 0.387). The bcl-2 expression was inversely proportional to TUNEL staining and steeper decrease was found in gray matter than in white matter (correlation coefficient, -0.875). CONCLUSION: Apoptosis increases as the injury grading elevated within 20gm-cm of impact. The p53 seems to promote apoptosis in white matter, but do not show proportional relationship with injury amount. Bcl-2 appeared to be protective to cell death due to apoptosis.
Animals ; Apoptosis* ; Cell Death ; Contusions* ; In Situ Nick-End Labeling ; Rats* ; Spinal Cord Injuries ; Spinal Cord*

PURPOSE: The study was aimed to detect the differences in the cell viability and the apoptosis induction after irradiation on normal and tumorigenic cells. MATERIALS AND METHODS: The study, that was generated for two human normal cells(RHEK, HGF-1) and two human tumor cells(KB, HT-1080), was tested using MTT assay at 1 day and 3 day after irradiation and TUNEL assay under confocal laser scanning microscope at 1 day after irradiation. Single irradiation of 0.5, 1, 2, 4, and 8 Gy were applied to the cells. The two fractions of 1, 2, 4, and 8 Gy were separated with a 4 hour time interval. The irradiation was done with 5.38 Gy/min dose rate using Cs-137 irradiator at room temperature. RESULTS AND CONCLUSIONS: 1. In 3-day group, the cell viability of HGF-1 cell was significantly decreased at 2, 4 and 8 Gy irradiation, the cell viability of KB cell was significantly decreased at 8 Gy irradiation and the cell viability of HT-1080 cell was significantly decreased at 4 and 8 Gy irradiation. 2. There was significant difference between RHEK and KB cell line in the cell viability of 3-day group at 8 Gy irradiation. There was significant difference between RHEK and HGF-1 cell line in the cell viability of 3-day group at 4 and 8 Gy irradiation. 3. There was a significantly decreased cell viability in 3-day group than those in 1-day group at 2, 4 and 8 Gy on HGF-1 cell, at 4 and 8 Gy on HT-1080 cell, at 8 Gy on KB cell. 4. We could detect DNA fragmented cells only on KB cell. Number of apoptotic cells of KB cell was significantly increased at 4 and 8 Gy irradiation. However, there was no correlation between cell viability and apoptosis. 5. On all 4 cell lines, there were no differences between single and split irradiation method in cell viability and apoptosis.
Apoptosis* ; Cell Line ; Cell Survival* ; DNA ; Humans ; In Situ Nick-End Labeling ; KB Cells ; Radiation Dosage*

We have studied morphologic characteristics and apoptosis on the fetal brain of the trisomy 16 mouse, a model for human trisomy 21 syndrome. This study was based on serial sections of the whole brain from a sample of sixteen trisomy 16 mice and forty-six age-matched control littermates from embryonic day (ED) 12 to ED 18. Trisomy 16 brains showed a reduction of telencephalic size and abnormal cortical development. At ED 13 trisomy 16 and control brains appeared similar. By ED 14 difference in the cortical thickness and telencephalic growth became evident, and by ED 16 a marked size difference had developed between the trisomy 16 and control brains. By ED 18, however, the thickness of the trisomy 16 cortex had increased considerably and was not significantly different with respect to the thickness and cross-sectional areas of the pallium and its constituent cortical layers. The cell density of the trisomy 16 cortex had persistently decreased before ED 17, when the cell density of control and trisomy 16 corteces was similar within each layer. At ED 18 cell density of trisomy 16 cortex in each layer increased. There was inverse relationship between a number of TUNEL positive apoptotic cells and cell density in the trisomy 16 brains. Our results suggest that developmental abnormalities of the trisomy 16 brain indicated developmental delay of the telencephalon growth, which may be caused by apoptosis rather than by a proliferation defect.
Animals ; Apoptosis* ; Brain* ; Cell Count ; Down Syndrome ; Humans ; In Situ Nick-End Labeling ; Mice* ; Telencephalon ; Trisomy*