All ceramic restorations have had a more limited life expectancy than metal ceramic crowns because of their lower strength. The relatively lower strength has limited the use of all-ceramic crowns to the areas where occlusal loads are lower. Therefore many researches have been done to increase the strength of all-ceramic crowns. IPS Empress 2 is a new type of lithium disilicate glass-ceramic with enhanced physical characteristics which has been in use clinically since 1998. Previous researches reported that the flexural strength of all-ceramic material was greater than 300MPa, and all-ceramic crowns can be used in staining or layering technique. The objective of this study was to investigate the influence of the thickness of IPS Empress 2 ceramic on fracture strength. Both staining technique and layering technique was investigated. Vita VMK was used as control. For all three groups, five specimens each of 0.8mm, 1.0mm, 1.4mm, 1.8mm, and 2.2mm thickness (a total of 75 specimens) were prepared. Control group: Vita VMK Porcelain specimens were prepared with dentine ceramic and liquid glazing was done. Group I: IPS Empress 2 were prepared with staining technique and stained twice and glazed once. Group II : IPS Empress 2 were prepared with layering technique and glazed after wash firing. The thickness and diameter of the specimen were measured and controlled after specimen preparation. Biaxial Flexure Test (ASTM Standard F394-78) was adopted as this test method produces results least affected by the edge condition of the specimens. Fracture strength was measured with Instron Universal Testing Machine. Conclusions are as follow : 1. The fracture strength was increase in order of control group, test group I, test group II. 2. Fracture strength of the group I(Empress 2 Staining) was 65.54 N in 0.8mm, 155.2 N in 1.0mm, 233.5 N in 1.44mm, 434.5 N in 1.8mm, and 600.1 N in 2.2mm. 3. Fracture strength of the group II (Empress 2 Layering) was 190.0 N in 0.8mm, 283.5 N in 1.0mm, 437.2 N in 1.4mm, 732.0 N in 1.8mm, and 1115.0 N in 2.2mm. 4. No statistical difference was found in flexural strengths according to thickness in a specified group(p>0.05).
Ceramics* ; Crowns ; Dental Porcelain ; Dentin ; Fires ; Life Expectancy ; Lithium

BACKGROUND: The proliferation of vascular smooth muscle cell(VSMC) is a part of the major pathogenic mechanism for atheroscle- rosis. It has been reported that L-type calcium channel plays a role in the VSMC proliferation in diabetic rats. But there is a little study results about the association between L-type calcium channel and VSMC proliferation by glucose concentrations in culture media. So we examined the association between voltage-dependent L-type calcium channel of VSMCs and the proliferative activity of vascular smooth muscle cells. METHODS: Rat aortic VSMCs were isolated from the aorta of OLETF rat by enzyme method. VSMCs were cultured in various concentrations of glucose(5.5, 25 mM). The VSMCs(1x104 cells in 24-well plates) were incubated in the presence of Bay K 8644 (10-6M) with/without verapamil(10-6M) for 48 hours. Then the proliferation was assessed by MTT(methylthiazole tetrazolium) assay and expression of L-type calcium channel mRNA was measured by RT-PCR. RESULTS: The proliferative ability and the expression of L-type calcium channel of cultured VSMCs were increased dose-dependently by the glucose concentrations(p<0.05). Bay K 8644 enhanced the proliferation of VSMC and verapamil blocked the incremental effects induced by Bay K 8644. CONCLUSION: These results suggest that L-type calcium channel may play a role in VSMC proliferation of OLETF rat.
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester ; Animals ; Aorta ; Calcium Channels, L-Type* ; Cell Proliferation* ; Culture Media ; Glucose* ; Muscle, Smooth, Vascular* ; Rats ; Rats, Inbred OLETF* ; RNA, Messenger* ; Verapamil

No abstract available.
Facial Asymmetry* ; Prognathism*

Extravasation of toxic chemotherapeutic 'agents cause severe skin ulceration and necrosis which often need secondary surgical intervention. Still, there were not established antidote agent in case of extravasation with mitomycin-c. Dimethyl sulfoxide is known as an effective chemical scavenger of toxic hydroxyl free radical and sodium thiosulfate also was demonstrated significant protector from mitomycin-c induced ulceration by a few experimental studies. Author investigated necrotic area of mitomycin-c injected site and compare to the effectiveness of topical treatment with dimethyl sulfoxide and intradermal injection of sodium thiosulfate according to starting times, forty five mice were divided into 3 groups. Control group(n=5) had no treatment after subcutaneous injection of mitomycin-c. Experimental group I and 11 were 20 mice treated dimethyl sulfoxide and sodium.
Animals ; Dimethyl Sulfoxide ; Injections, Intradermal ; Injections, Subcutaneous ; Mice ; Mitomycin* ; Necrosis* ; Skin Ulcer ; Sodium* ; Ulcer

Polyarteritis nodosa is systemic necrotizing vasculitis of medium and small-sized arteries and results in variable manifestations due to ischemia of the involving organs. Diagnosis can either be made pathologically by demonstrating necrotizing vasculitis of arteries or angiographycally by demonstrating small arterial aneurysm. We experienced a case of PAN with dilated cardiomyopathy, confirmed by clinical feature, renal biopsy, angiography and echocardiography.
Aneurysm ; Angiography ; Arteries ; Biopsy ; Cardiomyopathy, Dilated* ; Diagnosis ; Echocardiography ; Ischemia ; Polyarteritis Nodosa* ; Vasculitis

The various method have been used in reconstruction of the anophthalmic socket. Dermis-fat graft as an orbital implant is a relatively new approach. Dermis-fat graft restores the volume lost by enucleation, gives additional conjunctival lining and is permanent, with a minimal chance of absorption. Dermis-fat graft was used in reconstruction of an ophthalmic socket in our hospital. We found it successful procedure in case of primary enucleation, because it is permanent and it preserves the conjunctiva.
Absorption ; Conjunctiva ; Orbital Implants ; Transplants*

Respiratory distress syndrome (RDS) of preterm infants remains a significant cause of morbidity and mortality despite improvements in neonatal intensive care and artificial ventilatory techniques. After identification of the deficiency of pulmonary surfactant is major pathophysiologic basis in RDS, artificial surfactant replacement therapy in RDS was first successfully tested by Fujiwara and co-workers in 1980. therefore, exogenous surfactant replacement produced exellent results in improved clinical and repiratory status during the acute period and decreased incidence of late complications and mortality. According to comparison of administration timing between early (within 6 hours after birth) and late (after 6 hours)group, early replacement therapy is more effective in improving of clinical course and prognosis. Because of that, early, just after birth, recognition and detection of RDS is also important procedure. There are many investigations and methods for the detection of RDS in prenatal or postnatal period. Among then, stable microbubble rating (SMR) test was a simple method and SMR test has a higher diagnostic accuracy. To determine the relation of the SMR and purified natural surfactant (PNS) concentration in vitro, the author conducted each 5 times test of SMR method according to 5 groups of PNS concentration by using modified Pattle's method. The results were as follows: 1) The mean and standard deviation of SMR according to 5 groups of PNS concentration were 119.4 (15.0in 20mug PL (phospholipid)/ml, 452.2 (160.2 in 40mug PL/ml, 879.0 (93.4 in 60mug PL/ml, 1311.8 (274.8in80mug PL/ml, 1710.6(272.3 in 100mug PL/ml. 2) The regression curve of SMR and PNS concentration showed statistically significant relation(p<0.005). In conclusion, the SMR test was a good method in estimation of surfactant concentration in vitro and also in diagnosis of RDS recognized as a surfactant deficiency. In the future, we expected that prophylactic surfactant replacement therapy. immediate after birth, will be more popular in the field of neonatal care of RDS. So, we recommended the use of this method for early detection and serving optimal care of RDS.
Diagnosis ; Humans ; Incidence ; Infant, Newborn ; Infant, Premature ; Intensive Care, Neonatal ; Microbubbles* ; Mortality ; Parturition ; Prognosis ; Pulmonary Surfactants*

BACKGROUND: Circadian rhythms have been described for acute myocardial infarction, sudden cardiac death, cerebrovascular disease, ischemic heart disease, and ventricular arrhythmia. Most of studies reported that the frequency of ventricular permature contractions(VPC's) shows a peak in day time. We tried to see that the circadian rhythm of VPC's in hypertension and ischemic heart disease(IHD) patients. And we will also studied the relationship between heart rate and frequencey of VPC's. METHOD: Twenty four hour holter monitoring was performed in hypertensive patients (N=23), ischemic heart disease patients(N=25), and normal control group(N=30). We tested the circadian pattern of VPC's and heart rates and the relationships of the frequency of VPC's and heart rates. RESULT: In hypertension group, a peak incidence of heart rate is between 5 and 8 P.M., in ischemic heart disease group, between 3 and 6 P.M.. In control group, the heart rate shows a peak beteen 1 and 3 P.M.. The frequency of VPC's in hypertension group shows the first peak between 4 and 10 P.M., and the second peak beteen 7 and 10 A.M.. In ischemic heart disease group, they show a peak between 2 and 8 P.M..In control group, there was no circadian variation for the frequency of VPC;s. Both in hypertension and IHD patients group, there was significant correlation between the frequency of VPC's and the heart rates. CONCLUSION: It seemed that VPC' were more frequently occurred in relation to the increase of heart rate in the afternoon, in hypertensive and ischemic heart disease patients.
Arrhythmias, Cardiac ; Circadian Rhythm ; Death, Sudden, Cardiac ; Electrocardiography, Ambulatory ; Heart ; Heart Rate ; Humans ; Hypertension* ; Incidence ; Myocardial Infarction ; Myocardial Ischemia* ; Ventricular Premature Complexes*

BACKGROUND: Established risk factors for coronary artery disease include smoking, hypertension, diabetes mellitus and hypercholesterolemia. However, these account for less than 50% of the actual incidence of coronary artery disease and the importance of other risk factors is being increasingly realized. It has been known that insulin resistance associated with hyperinsulinemia is a pivotal link to several risk factors of coronary artery disease, including hypertension, glucose intolerance, dyslipidemia and obesity. Recently both experimental and clinical studies have produced evidence suggesting that high plasma insulin level may promote the development of atherosclerotic vascular diseasa. Several prospective studies showed independently that high plasma insulin is associated with an increased risk of major coronary artery disease. In our study, plasma glucose, insulin and C-peptide level were determined with oral glucose tolerance test to assess the insulin resistance or hyperinsulinemia as a risk factory of coronary artery disease. METHOD: From September 1993 to April 1995, after excluding patients with hypertension, diabetes mellitus, hypercholesterolemia and obesity, 17 patients with significant coronary artery stenosis and 10 control subjects with normal coronary finding were selected among the 226 patients who undertook coronary angiography. In the 17 cases(M:F=15:2) of coronary artery disease group, the mean age was 54+/-10 years, and in the 10 cases(M:F=8:2) of control group, 51+/-9 years. All were matched for age, gender and body mass index. Blood pressure, lipid and lipoprotein were measured and smoking history was assessed. Glucose, insulin and C-peptide responses to oral glucose tolerance test were also determined. RESULT: 1) There was no significant difference in systolic and diastolic and diastolic blood pressure, total-cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol, ApoA and smoking history except ApoB between the subjects with coronary artery disease and normal control subjects. 2) In oral glucose tolerance test, the plasma glucose levels were not significantly different in the two groups. plasma insulin and C-peptide levels at 60 and 120 minutes were higher in the patient group than control, but the results lack statistical significance. The area under the insulin curve and C-peptide curve were larger in patient group than control, but the result lack statistical significance also. CONCLUSION: Although our study dose not prove the hypothesis that insulin resistance or hyperinsulinemia is statistically an independent risk factor for coronary artery disease, this study showed the tendency of insulinresistance to be correlated with development of coronary artery disease. As this study has limitations due to small sample size, further study is required to confirm the role of hyperinsulinemia using a larger sample size.
Apolipoproteins A ; Apolipoproteins B ; Blood Glucose ; Blood Pressure ; Body Mass Index ; C-Peptide ; Coronary Angiography ; Coronary Artery Disease* ; Coronary Stenosis ; Coronary Vessels* ; Diabetes Mellitus ; Dyslipidemias ; Glucose ; Glucose Intolerance ; Glucose Tolerance Test ; Humans ; Hypercholesterolemia ; Hyperinsulinism ; Hypertension ; Incidence ; Insulin Resistance* ; Insulin* ; Lipoproteins ; Obesity ; Plasma ; Prospective Studies ; Risk Factors* ; Sample Size ; Smoke ; Smoking ; Triglycerides

Cloning, sequencing and expressing in E. coli of the thymidine kinase (TK) gene of Herpes simplex virus type-1 (HSV-1) strain F was investigated. The TK gene, located in the BamHI 3.74 kb DNA flagment of the plasmid PHLA-12, was amplified by polymerase chain reaction (PCR). The 1,131 kb PCR product was cloned into the BamHI and BglII sites of pQE-30, and named pQE-TK recombinant. The TK gene was subcloned into the BamHI and BglII sites of pQE-30, and named pQE-TK recombinant. The nucleotide sequence of the 1,131 kb TK gene was determined, and the GC content was 65.13%. There were deduced 367 amino acid residues with a total molecular weight of 43 kDa. The weight was confirmed by the protein produced by E. coli M15/pQE-TK on the SDS-PAGE and Western blot. The production of the TK protein in the IPTG induced cells was measured over 4 h. At the end of 1, 2 and 3 h the level increased by 146,204 and 242%, respectively. The amount of the protein at the highest fraction Purified with Ni-NTA resin chromatography was 0.68 ug Per ml. The soluble state TK protein was present in the cytoplasm. In these results the F strain was different in base sequence and amino acid sequence from that of the CL101 strain, which caused difference in their strains.
Amino Acid Sequence ; Base Composition ; Base Sequence ; Blotting, Western ; Chromatography ; Clone Cells* ; Cloning, Organism* ; Cytoplasm ; DNA ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli* ; Escherichia* ; Herpesvirus 1, Human ; Isopropyl Thiogalactoside ; Molecular Weight ; Plasmids ; Polymerase Chain Reaction ; Simplexvirus ; Thymidine Kinase* ; Thymidine*