Experimental findings have suggested that the metabolic activities of articular cartilage can be influenced by mechanical stimuli. Our recent mathematical analysis predicted that cyclic compressive loading may create periods of intermittent negative hydrostatic pressure within the cartilage extracellular matrix. Therefore, we hypothesize that intermittent negative hydrostatic pressure, created in the cartilage extracellular matrix during dynamic compression, has a stimulative effect on the biosynthesis of chondrocytes. In order to test this hypothesis, the present study developed a custom designed negative pressure generator to subject a monolayer culture of chondrocytes to an intermittent negative pressure. It was found that the intermittent negative pressure produced a 40% increase in proteoglycan and a l7% increase in non-collagenous protein synthesis during the pressurization period(p (0.05). The collagenous protein synthesis was not affected by the intermittent negative pressure regimen used in this study. After the intermittent negative pressurization, the metabolic activities of the chondrocytes returned to normal(control level). The intermittent negative pressure also produced an increase in the mRNA signals for aggrecan. Therefore, we conclude that intermittent negative pressure may be one of the major mechanical stimulators of chondrocytes in articular cartilage during dynamic compression.
Aggrecans ; Cartilage ; Cartilage, Articular ; Chondrocytes* ; Collagen ; Extracellular Matrix ; Hydrostatic Pressure* ; Metabolism* ; Proteoglycans ; RNA, Messenger

The human pattern reversal retinal potential(PRRP) is a bioelectrical response that reflects neural activity generated in the proximal retina. Visual diseases which affect the retinal ganglion cells and the optic nerve often produce signifjcant reductions in the amplitude of the PRRP. PRRP amplitude reductions are freguently obseved in the patients with primary open angle glaucoma. This study was designed to determine whether patients with ocular hypertension whieh are at risk of developing glaucoma also exhibit PRRP amplitude reductions. 1. As compared to the control group the glaucoma patients showed decreased P1-N2 amplitude and a significant delay of Visual evoked potential(VEP) latency. The retinocortical time was delayed(72%) and PRRP P1-N2 amplitude was decreased in 30 percents of the ocular hypertensive patients. 2. In the glaucoma and ocular hypertension, VEP P1 latency has more diagnoic value than PRRP P1 latency. 3. VEP and PRRP show more diagnostic values and these tests are essential for early diagnosis in the glaucoma.
Early Diagnosis ; Evoked Potentials, Visual ; Glaucoma ; Glaucoma, Open-Angle ; Humans ; Ocular Hypertension* ; Optic Nerve ; Retina ; Retinal Ganglion Cells ; Retinaldehyde*

The authors were experienced a case of metastatic adenocarcinoma of the left orbit originating from the lung in a 66 years old Korean male. Most outstanding of his complaint were protrusion of left eyeball, visual disturbance and severe ocular pain of left eye. The tumor was removed because of severe left ocular pain and then, he received with Co. 60 irradiation as much as 4,000 rad. Since then, exophthalmos was slightly reduced but left ocular pain was persisted.
Adenocarcinoma* ; Aged ; Exophthalmos ; Humans ; Lung* ; Male ; Orbit*

No abstract available.
Aging*

Cavernous hemangiona is the most common primary orbital tumor. The authors experienced two cases of orbital cavernous hemangioma recently. In the first case, a 8-year old Korean girl visited our department in Apr. 11,1978 with right exophthalmos which had showed progressive enlargement in 2 years. The computed tomographic examination of the orbit revealed irregular, partly lobulated mass density with an attenuation value approximating soft tissue in the medial portion of right retrobulbar region. In the second case, a 6-year old Korean girl visited our department in Apr. 16, 1979 with left exophthalmos showed in 3 weeks after trauma. The computed tomographic examination of the orbit revealed well defined mixed soft mass density in the left rerobulbar space. The mass were excised by Killian's approach and histopathologic examination revealed cavernous hemangioma.
Child ; Exophthalmos ; Female ; Hemangioma, Cavernous* ; Humans ; Orbit*

No abstract available.
Humans ; Hypersensitivity* ; Phenytoin*

This study is the retrospective evaluation of ninety-six patients with biopsy-proven carcinoma of nasopharynx treated with radiotherapy at Yonsei University, College of Medicine, radiation Oncology from January 1971 to December 1985. Patient's age ranged from 15 to 71 years with a median age of 49 years. Fifty-two point five percent of local control and 47.5% of actuarial 5 year survival were achieved with radical radiotherapy. Five year survival rate for Stage I & II, III and IV were 75.0%, 74.6% and 41.4%, respectively. Distant metastasis rate was related with N stage (N1 12.5%, N1 0%, N2 23.5%, N3 32.1%) and histologic type (lymphoepithelioma 41.7%, squamous cell carcinoma 6.5%) but not with T stage. Thirty-one of sixty-seven patient covered adequate radiation field received induction chemotherapy. However induction chemotherapy dose not appear to improve over all survival.
Carcinoma, Squamous Cell ; Humans ; Induction Chemotherapy ; Nasopharynx ; Neoplasm Metastasis ; Radiation Oncology ; Radiotherapy* ; Retrospective Studies ; Survival Rate

A polyetherurethane (PU) film containing 0.1% zinc diethyldithiocarbamate (ZDEC) is the international standard reference material for testing the in vitro cytotoxicity of polymer based biomaterials. Nowadays, culturing L929 or BALB/3T3 cells in direct contact or in an extract dilution condition is the most frequently using method for evaluating the cytotoxicity from biomaterials and medical devices. However, the results often vary, because it is directly related to the cellular functions and the mechanism of the toxicity of the contacting cells. In this study, 13 cell lines originating from various tissues were used to detect the cytotoxic activities of a PU film containing 0.1% ZDEC (PU-ZDEC). The correlation between the reactivity zone size and the relative cytotoxicity by quantifying the released total protein from each cell in the direct contact testing method was investigated. Hepa-1c1c7 cells demonstrated the highest sensitivity in the reactivity zone size, while CHO/dhFr(-) cells were the most sensitive in terms of the relative cytotoxicity. A correlation between the two processes in each cell line was not found (r=-0.478). In the extract dilution method, which involved cultivating the cells in the medium with various ZDEC concentrations prepared by diluting the PU incubation, the cytotoxicity increased with increasing ZDEC concentration in all cell lines. The BALB/ 3T3 cells demonstrated the highest sensitivity in the extract dilution method. No correlation in a comparison of the relative cytotoxicity from the direct contact method with the extract dilution method in each cell line, was found (r=-0.445). In this experiment, Hepa-1c1c7, BALB/3T3, CHO/dhFr(-) and L-929 cells among the 13 types of cell lines were the sensitive cell lines according to the two methods. The preliminary results suggest that a comparison of at least one or more cytotoxicity testing methods and many cell lines is necessary for an in vitro cytotoxicity test of biomaterials.
Animal ; Cell Line ; Cell Survival/drug effects ; Ditiocarb/*toxicity ; Hamsters ; Human ; Mice ; Polyurethanes/*toxicity ; Support, Non-U.S. Gov't ; Toxicology/*methods

BACKGROUND: Legionella pneumophila has been recognized as an important cause of community-acquired pneumonia(CAP) requiring hospitalization. However, epidemiological data on the occurrence of legionella-related pneumonia is unavailable in Korea. The purpose of this study was to evaluated the etiological imprtance of legionella pneumophila serogroup 1 in patients hospitalized with CAP. METHOD: The CAP patient over 16 year-old were recruited from July 1999 to June 2000 at the Chunchon Sacred Heart Hospital. Fifty four patients (male 29, female 25, average age 63.8±15.3) were included in this study. A diagnosis of a legionella pneumophila infection was based on a urinary antigen test using the Binax Company enzyme immunoassay. The severity of pneumonia was assessed using the Fine's PORT scoring system. RESULT: The average Fine's PORT score was 99.7(±44.9). According to the risk classification proposed by the Infectious Disease Society of America, the number of patients in each class(from class I to class V) were 6(11.1%), 13(24.1%), 9(16.7%), 14(25.8%), and 12(22.2%), respectively. Thirty two patients(59.3%) were initially admitted to the intensive care unit. The mortality rate was 16.7%(9 in 54). In all patients, urinary antigens to Legionella pneumophila serogroup 1 were not detected. CONCLUSION: Legionella pneumophila may play little role in causing adult CAP in Korea. Therefore, the routine use of macrolide in the empirical treatment of the CAP patients based upon the ATS guidelines(1993) in Korea should be reevaluated.
Adult ; Americas ; Classification ; Communicable Diseases ; Diagnosis ; Female ; Gangwon-do ; Heart ; Hospitalization ; Humans ; Immunoenzyme Techniques ; Intensive Care Units ; Korea* ; Legionella pneumophila* ; Legionella* ; Legionnaires' Disease ; Mortality ; Pneumonia*

BACKGROUND AND OBJECTIVES: We investigated the predictors of the recovery of depressed left ventricular ejection fraction (LVEF) in patients with moderate or severe left ventricular (LV) systolic dysfunction after acute myocardial infarction (MI). SUBJECTS AND METHODS: We analyzed 1307 patients, who had moderately or severely depressed LVEF (<45%) on echocardiography soon after acute MI and who underwent a follow-up echocardiography, among 27369 patients from the Korea Working Group on the Myocardial Infarction Registry. Patients were categorized into two groups according to recovery of LVEF: group I with consistently depressed LVEF (<45%) at the follow-up echocardiography and group II with a recovery of LVEF (> or =45%). RESULTS: Recovery of LV systolic dysfunction was observed in 51% of the subjects (group II, n=663; DeltaLVEF, 16.2+/-9.3%), whereas there was no recovery in the remaining subjects (group I, n=644; DeltaLVEF, 0.6+/-7.1%). In the multivariate analysis, independent predictors of recovery of depressed LVEF were as follows {odds ratio (OR) [95% confidence interval (CI)]}: moderate systolic dysfunction {LVEF > or =30% and <45%; 1.73 (1.12-2.67)}, Killip class I-II {1.52 (1.06-2.18)}, no need for diuretics {1.59 (1.19-2.12)}, non-ST-segment elevation MI {1.55 (1.12-2.16)}, lower peak troponin I level {<24 ng/mL, median value; 1.55 (1.16-2.07)}, single-vessel disease {1.53 (1.13-2.06)}, and non-left anterior descending (LAD) culprit lesion {1.50 (1.09-2.06)}. In addition, the use of statin was independently associated with a recovery of LV systolic dysfunction {OR (95% CI), 1.46 (1.07-2.00)}. CONCLUSION: Future contractile recovery of LV systolic dysfunction following acute MI was significantly related with less severe heart failure at the time of presentation, a smaller extent of myonecrosis, or non-LAD culprit lesions rather than LAD lesions.
Diuretics ; Echocardiography ; Follow-Up Studies ; Heart Failure ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; Korea ; Multivariate Analysis ; Myocardial Infarction ; Prognosis ; Stroke Volume ; Troponin I