Increased melanin pigmentation following ultraviolet irradiat.ion is due to increasing tyrosinase activity and multiplicatian of functioning melanocytes. After UV-irradiation, the size of melanocytes increases, and melanocyte dendrites elongatc, and branch. In this experiment, we induced the activation of melanocyts in the epidermis of C57BL black mice by ultraviolet-B(UVB) irradiation and observcd ihe effect of azelaic acid and retinoic acid on the UVB activated epidermal melanocytes. Sixty C57BL black mice were irradiated by UVB 100mJ/cm daily for 10 days, and then azeiaic acid and retinoic acid were topically applied daily for 7 weeks. For the estimation of morphologic change of epidermal melanocytes, light microscopic observation with split DOPA stain was performed at the end of the 1st, 3rd, 5th and 7th week of topical application. The results are summerized as follows : 1. The number, size and circumference of DOPA-positive epidermal melanocytes were significantly decreased in 20% azelaic acid applied group and 30% azelaic acid and 0.05% retinoic acid applied group. 2. In 20% azelaic;i.cid and 0.05% retinoic acid applied group, the number, size and circumference of DOPA-positive epidermal melanocytes were nore significantly decreased than in 20% azelaic acid applied group. In summary, the present study suggets that azelaic acid act as a depigmenting agent on epidermal melanocyte; and such depigmenting effect of azelaic acid was increased by addition of retinoic acid.
Animals ; Dendrites ; Dihydroxyphenylalanine ; Epidermis ; Melanins ; Melanocytes* ; Mice* ; Monophenol Monooxygenase ; Pigmentation ; Tretinoin*

PURPOSE: The principal cause of treatment failure in osteosarcoma is drug resistance. Multidrug resistance (MDR), mediated by P-glycoprotein (P-gp), is an in vitro phenomenon, resulting in becoming cross-resistant to structurally unrelated drugs. P-gp expression was related to drug resistance, prognosis and recurrence in osteosarcoma. p53 gene regulates genomic stability. Mutant p53 protein causes loss of tumor suppression. Co-expression of mutant p53 protein and P-gp was related to short survival, malignancy and drug resistance in malignant tumors. Wild type p53 protein in SaOS-2 cell line down-regulates the transcription of mdr1 gene. The purpose of this study was to evaluate the expression of mutant p53 protein and P-gp in osteosarcoma and its prognostic significance. MATERIALS AND METHODS: Fifty-two archival pathologic tissues were examined with immunohisto-chemistry. Positive expression was defined if more than 10% of tumor cells were stained. RESULTS: Expression rate of mutant p53 protein was 63% and rate of P-gp was 35%. Correlation between mutant p53 protein and P-gp expression was significant (P=0.0008). Co-expression of mutant p53 protein and P-gp was the strongest prognostic factor for shorter survival by multivariate analysis (P=0.0004). CONCLUSIONS: Nuclear accumulation of mutant p53 protein was significantly related to P-gp expression in osteosarcoma, Co-expression of mutant p53 protein and P-gp is an independent unfavorable prognostic factor in osteosarcoma
Cell Line ; Drug Resistance ; Drug Resistance, Multiple ; Genes, p53 ; Genomic Instability ; Immunohistochemistry ; Multivariate Analysis ; Osteosarcoma* ; P-Glycoprotein* ; Prognosis ; Recurrence ; Survival Analysis ; Treatment Failure

BACKGROUND: The circadian rhythm of circulating melatonin is regulated by the endogenous oscillators, the suprachi-asmatic nuclei, and entrained by the light-dark cycle of the environment, but it seems that the rhythm can be affected by variable lesions outside the retina-pineal pathway. We intended to know how acute cerebral infarction affects on the cir-cadian rhythm of plasma melatonin secretion. METHODS: Plasma melatonin level was measured from 64 patients with acute cerebral infarction. On admission, blood samples were collected by venipuncture at 2AM, 4AM, 10AM, and 2PM and melatonin level was measured by radioimmunoassay. The state of consciousness of each patient was assessed clini-cally and the infarction site and size were evaluated clinically and radiographically. RESULTS: Among 64 patients with acute cerebral infarction, dramatic blunting or obliteration of nocturnal melatonin surge in the blood was found in 29 patients. The circadian rhythm of melatonin secretion was absent in 12 of 35 alert patients, in 10 of 20 drowsy patients, and in 5 of 7 stuporous patients. Melatonin secretion into plasma was markedly decreased in all 2 comatose patients. Of 14 patients with brainstem lesions, 8 patients showed decreased melatonin levels with the absence of a nocturnal rise, although most of them were alert. CONCLUSIONS: This study suggests that brainstem and the initial mental state might contribute to the regulation of the circadian rhythm of plasma melatonin even though the lesion does not involve the retina-pineal pathway, but further extensive study is required to elucidate it. (J Korean Neurol Assoc 19(4):359~363, 2001)
Biological Clocks ; Brain Stem ; Cerebral Infarction* ; Circadian Rhythm* ; Coma ; Consciousness ; Humans ; Infarction ; Melatonin* ; Phlebotomy ; Photoperiod ; Pineal Gland ; Plasma ; Radioimmunoassay ; Stupor

Angiographic findings were analysed in 11 cases of Behcet'sdisease which was diagnosed clinically in Seoul national University Hospital from July 1982 to June 1983. Arterial involvement was noted in 5 cases and venous involvement in 6 cases respectively. Arterial aneurysm and occlusion were arteriographic findings. Arterial aneurysm was noted at large arteries in all 5 cases and multifocal involvement was noted in 4 cases. Characteristic finding of arterial involvement was protruding saccular aneurysm. Venous involvement was thrombotic occlusion of deep veins in iliac, femoral and tibial areas in all 6 cases. Behcet's disease should be differentiated whenever these arterial or venous angiographic findings are revealed in a young adult.
Aneurysm ; Arteries ; Humans ; Seoul ; Veins ; Young Adult

No abstract available.
Ascitic Fluid* ; Endometriosis* ; Female ; Humans ; Interleukins*

Moyamoya disease is characterized by a bilateral progressive narrowing of the distal internal carotid and proximal portions of the anterior and middle cerebral arteries. The cerebral vessels of the 11 to 14 mm embryonic period are extremely similar to these moyamoya vessels. The vertebral arteries unite with a contralateral homologue to form the basilar artery during embryonic development and rarely, the failure of complete fusion results in duplication of these arteries. It is well known that moyamoya disease sometimes is accompanied by persistent primitive arteries, cerebral aneurysm, or rarely arteriovenous malformation. However, no case of the moyamoya disease with complete duplication of basilar artery has been previously reported. These two types of vascular abnormality are probably associated in certain developmental period, and moyamoya disease causes hemodynamic load in the basilar artery system as a collateral pathway and these effects are also involved in duplication of basilar artery. The relationship between these two varieties of vascular abnormality and possible pathogenesis of the moyamoya disease are discussed.
Aneurysm ; Arteries ; Arteriovenous Malformations ; Basilar Artery* ; Cerebral Arteries ; Embryonic Development ; Female ; Hemodynamics ; Middle Cerebral Artery ; Moyamoya Disease* ; Pregnancy ; Vertebral Artery

Pilomatricoma(calcifying epithelioma of Malherbe) is a rare benign turner of the skin which develops from immature hair matrix cells. The diagnosis of the calcifying epithelioma of Malherbe is only rarely made on clinical ground but is, as a rule, easily made by histologic examination. We briefly report 2 cases of pilomatricoma occurring on upper eyelid with review of the literature.
Carcinoma ; Diagnosis ; Eyelids* ; Hair ; Pilomatrixoma* ; Skin

Unilateral adsence of a pulmonary artery is frequently undiagnosed. Unless this entity is recognized, a patient with a potentially curable lesion may become inoperable. The importance of considering unilateral absence of a pulmonary artery in the diffirential diagnosis of cyanotic congenital heart disease and pulmonary hypertension has become clear. We exeperienced a case of congenital isolated unilateral absence of it. pulmonary artery confirmed by clinical features, lung scan, echocardiogram and angiogram.
Diagnosis ; Heart Defects, Congenital ; Humans ; Hypertension, Pulmonary ; Lung ; Pulmonary Artery*

STATEMENT OF PROBLEM: One of common problems associated with single teeth dental implant prosthetic is the loosening of screws that retain the implants. PURPOSE: The maintenance of screw joint stability is considered a function of the preload achieved in the screw when the suggested initial tightening torque is applied. The purpose of this study was to investigate acquired preload after initial clamping torque for estimating screw joint stability. MATERIAL AND METHODS: A comparative study on the effect of initial clamping of two types of implant systems with different connections was conducted. Three dimensional non-linear finite element analysis is adopted to compare the characteristics of screw preloads and stress distributions between two different types of implant systems composed with abutment, screw, and fixture under the same loading and boundary conditions. RESULTS: 1. When the initial clamping torque of 32Ncm was applied to the implant systems, all types of implants generated the maximum effective stress at the first helix region of screw. 2. Morse taper connection types of implants generate lower stress distributions compared to those by butt joint connection types of implants due to large contact surface between abutment and fixture. 3. The internal types of implant systems with friction grip type implant systems have higher resistance to screw loosening than that of the external types of implant systems since the internal types of implant systems generated larger preload than that generated by the external types for the same tightening moments.
Constriction* ; Dental Implants ; Finite Element Analysis* ; Friction ; Hand Strength ; Joints ; Tooth ; Torque

No abstract available.
Gynecology*