Biomedical subjects

Chang Sub Lee

Publications and source records attributed to Chang Sub Lee.

4 recordsLinked to original sources

PubMed2006

Optic pathway glioma: outcome and prognostic factors in a surgical series.

OBJECTS: The goals of this study were to evaluate the surgical outcomes of optic pathway glioma (OPG) and to analyze the prognostic factors related to the progression-free survival. MATERIALS AND METHODS: A retrospective review was conducted on 33 patients who underwent surgery for OPG; these included 15 male and 18 female patients with a mean age of 8.3 years. The mean duration of follow-up was 52 months. RESULTS AND CONCLUSIONS: The preservation rate of ipsilateral vision was 25%, while that of contralateral vision was 83% (P<0.001). There was no remarkable endocrine improvement after surgery. The overall and progression-free survival rates at 5 years were 93.6 and 52.4%, respectively. In our study, the predictors for tumor progression were children younger than 5 years of age (p=0.023) and of female gender (p=0.022). Because of the variable course of OPG, treatment policy should be optimized individually according to patient's status.

Adolescent↗

PubMed2006

Cytokinetics of secondary neurulation in chick embryos: Hamburger and Hamilton stages 16-45.

OBJECTIVES: In an attempt to understand the events in the secondary neurulation in embryonic stage, we investigated cytokinetic changes in the tail bud of normal developing chick embryos. MATERIALS AND METHODS: We investigated chick embryos of Hamburger and Hamilton stages 16-45 by staining for proliferating cell nuclear antigen (PCNA) and applying the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) method. RESULTS AND CONCLUSIONS: The cytokinetics of secondary neurulation have several distinctive properties: a general chronological delay compared to primary neurulation; absence of ventrodorsal differences; larger rostrocaudal differences; and degeneration of the distal end of the spinal cord in the later stages of development. These differences in morphogenetic and cytokinetic behavior between primary and secondary neurulation may help to improve our understanding of anomalies originating during secondary neurulation.

Age Factors↗

PubMed2005

Unilateral (probable) moyamoya disease: long-term follow-up of seven cases.

OBJECTS: Some cases of unilateral involvement have angiographic findings on the affected side which resemble those of definite cases of moyamoya disease (MMD). We analyzed these cases to determine whether the entity "unilateral MMD" actually exists and whether unilateral involvement represents only the early phase of the pathologic process found in definitive bilateral disease. METHODS: Between 1988 and 2000, seven cases of unilateral MMD were evaluated. The male-to-female ratio was 2:5, mean age was 5.1 years (7 months to 8 years), and mean follow-up duration was 64.7 months. The presenting symptoms of these cases were similar to those of definite MMD, and no familial occurrence was found. Two of the seven unilateral MMD cases showed progression to bilateral involvement. However, the remaining cases showed no evidence of contralateral progression during the follow-up period. CONCLUSIONS: Most cases of unilateral MMD seem to be an unusual form of stenoocclusive process of the proximal intracranial arteries, distinguishing the condition from definite MMD. Surgical treatment on the symptomatic side and close observation for signs of bilateral involvement are necessary.

Cerebral Angiography↗

PubMed2005

Aggressive vestibular schwannomas showing postoperative rapid growth - their association with decreased p27 expression.

Vestibular schwannomas (VSs) are relatively slow growing tumors. However, some rapidly regrow or recur after surgical resection. The objective of this study was to identify those molecular characteristics predicting rapid recurrence after surgical resection. Immunohistochemically determined expressions of several cell cycle regulators and apoptosis-associated proteins in 12 cases of aggressive VS (AVS) and in 15 control cases of usual VS (UVS) cases were compared. The expressions of p53 and Bax (pro-apoptotic protein), Bcl-2 (anti-apoptotic protein), Fas, and Fas-L (apoptotic death receptor and ligand), caspase 3 (apoptotic effector caspase proteins), and p27 and p21 (cyclin-dependent kinase inhibitors) were analyzed using tissue array blocks. Loss of p27 expression was observed in 8 of 12 AVS cases (67%) and in 3 UVS cases (20%); p21 was expressed in all cases. Loss of Bax was observed in 3 AVS and 3 UVS cases. The anti-apoptotic protein, Bcl-2, was expressed in 9 AVS (75%) and 11 UVS (73%), and p53, Fas-L, and caspase 3 were negative and Fas was positive in all AVS and UVS cases. Of these, only the loss of p27 was statistically significant (P = 0.02). The loss of p27 in AVS may explain the unusually high proliferative potential of AVS versus UVS, and p27 may be a predictor of VS aggressiveness. The expressions of other apoptosis associated proteins were not significantly different in the two groups. This may be the first report to identify a molecular entity associated with aggressive VS. However, further studies are required.

Cell Proliferation↗