BACKGROUND: The effects of a newly synthesized potassium channel opener, KR-30816((-)(nitro-2-hydroxymethyl-2-methy-2H-1-benzopyran-4-y1)pyridine oxide) on the action potential of papillary muscles of guinea pigs and the ATP-sensitive potassium channel current(IKATP) of single ventricular muscle cells of rats were examined to make clear its action mechanism of the KATPchannel. METHODS: We used the conventional microelectrode and the excised inside-out patch configuration. RESULTS: KR-30816 caused a shortening of the action potential duration in dose-dependent manner, which was inhibited by glibenclamide(3microM). Before run-down of the K+channel, KR-30816 activated the cardiac ATP-sensitive K+ channel only in the presence of ATP and shifted the dose-response relation curve between [ATP]i and the channel activity to the right in parallel. After run-down of the KATP channel, KR-30816 did not after the channel opening either in the absence or in the presence of UDP. CONCLUSION: These results suggest that KR-30816 antagonizes the inhibitory effect of ATP on the KATPchannel in a competitive manner, thereby enhancing the channel openings.
Action Potentials ; Adenosine Triphosphate ; Animals ; Guinea Pigs ; Heart ; Microelectrodes ; Muscle Cells ; Papillary Muscles ; Potassium Channels* ; Potassium* ; Rats ; Uridine Diphosphate

BACKGROUNG AND OBJECTIVES: It was reported that low molecular weight heparin (LMWH) was more effective than unfractionated heparin in patients with acute coronary syndrome. Recent studies have shown that the pathophysiology of restenosis in stented lesions was different from those of nonstented lesions. Treatment strategies designed to limit cellular proliferation that were ineffective in nonstented lesions may be efficacious in reducing in-stent restenosis. This study was aimed to compare the clinical and angiographic results of LMWH (nadroparin) after coronary stenting with those of conventional ticlopidine regimen. MATERIALS AND METHODS: Patients were eligible for inclusion if they had angina and/or objective evidence of myocardial ischemia, and a significant (>50%) stenosis that was documented on a recent coronary angiogram. After stenting, prospective randomized comparison study was performed. Patients were randomly assigned to either nadroparin (200 IU/kg, sc, bid) or ticlopidine (250 mg bid) plus aspirin (200 mg qd) treatment groups. Repeat coronary angiography (KERN=*)was performed at 236+/-90days after stenting, and quantitative coronary angiographic analysis (QCA) was done. RESULTS: Intracoronary stent implantation was performed in eighty five lesions in eighty one patients (ticlopidine:40, nadroparin:41). There was no significant difference in any baseline clinical/angiographic variables between the two treatment groups. There were no subacute stent thrombosis, infarction and death in both groups. Six-month event-free survival was 36 (90%) in the ticlopidine group and 35 (85.4%) in the nadroparin group. Follow-up quantitative angiographic data such as late loss (1.35+/-0.70 vs 1.32+/-0.69), loss index (0.53+/-0.70 vs 0.56+/-0.23) and restenosis rate (36% vs 25.8%) were not different between ticlopidine and nadroparin groups. CONCLUSION: Effects of nadroparin were not different from those with ticlopidine therapy in the prevention of restenosis and subacute stent thorombosis after coronary stenting. Clinical outcomes between two strategies were similar. Low molecular weight heparin may be an alternative to ticlopidine in patients that ticlopidine cannot be administered because of severe adverse effects.
Acute Coronary Syndrome ; Aspirin ; Cell Proliferation ; Constriction, Pathologic ; Coronary Angiography ; Disease-Free Survival ; Follow-Up Studies ; Heparin ; Heparin, Low-Molecular-Weight ; Humans ; Infarction ; Myocardial Ischemia ; Nadroparin* ; Prospective Studies ; Stents* ; Thrombosis ; Ticlopidine*

PURPOSE: To compare chest radiographic findings of pulmonary tuberculosis in non-AIDS immunocom- promised adult patients with those in immunocompetent patients. MATERIAL AND METHOD: Eighty six patients who had pulmonary tuberculosis were included in the study. Of these, 41 were non-AIDS immunocompromised adult patients and 45 were immunocompetent adult patients. Chest radiographs obtained from 86 patients were retrospectively evaluated with regard to the followings ;the anatomic distribution and extent of tuberculous lesions, typical or atypical patterns of radiographic findings. We then compared the results in non-AIDS immunocompromised adult patients with those in immunocompetent adult patients. RESULTS: The characteristic manifestation of pulmonary tuberculosis was a tendency of pulmonary lesions to localize in the apico-posterior segments of the upper lobe and the superior segment of the lower lobe in both groups but more wide distribution such as the anterior segment and the lingular segment of the upper lobe and the basal segments of the lower lobe was frequently identified in non-AIDS immunocompromised adult patients, and also bilateral, multisegmental and multilobular extents were common findings. in immunocompetent adult patients, more common findings were in local exudative and productive lesions and several cavities in preferential sites. Atypical plain radiographic findings were more common in non-AIDS immunocompromised adult patients, and which were multiple cavitary lesions, wide extent of bronchogenic spread and tuberculous pneumonia, and .miliary disseminations and mass like lesions. CONCLUSIONS: Pulmonary tuberculosis in non-AIDS immunocompromised adult patients is characterized by frequent bilateral distribution, wide pulmonary extent, and atypical radiographic findings.
Adult* ; Humans ; Pneumonia ; Radiography, Thoracic ; Retrospective Studies ; Tuberculosis, Pulmonary*

BACKGROUND: Diffusion-weighted MR imaging (DWI) was designed to detect the random molecular otion of water in tissue. DWI has gained increasing interest recently because it can demonstrate yperacute stroke earlier than any other imaging methods so far. The purpose of our study was to etermine the clinical usefulness and significance of DWI compared with those of Fast Spin Echo T2-weighted image (SE T2WI) and Fluid Attenuated Inversion Recovery (FLAIR) image in acute and subacute ischemic stroke. METHOD: Twenty-five adult patients with clinical diagnoses of acute or subacute cerebral infarctions were imaged with fast SE T2WI, FLAIR and DWI using a 1.5-T image. RESULTS:All the patients had areas of high signal intensity indicating acute or subacute lesions on DWI and these lesions provide an excellent clinicoanatomic correlation. CONCLUSIONS: DWI is most useful in the diagnosis and localization of acute or subacute lacuna or subcortical infarction in patients with preexisting chronic infarctions or white matter hyperintensity showing high signal intensity similar to acute or subacute infarctions on T2WI or FLAIR image.
Adult ; Brain ; Cerebral Infarction ; Diagnosis ; Diffusion* ; Humans ; Infarction ; Magnetic Resonance Imaging ; Stroke*

No abstract available.
Female ; Humans ; Marriage*

PURPOSE: To compare, with the use of chest radiographic findings, improvement and complications in newborns treated with exogenous surfactant for hyaline membrane disease(HMD), and an untreated control group. MATERIALS AND METHODS: Thirty-six patients with HMD were randomly assigned to a control group (n=18) or surfactant treated group (n=18). As part of an initial evaluation of their pulmonary status, we then performed a retrospective statistical analysis of chest radiographic findings obtained in exogenous surfactant treated and untreated infants within the first 90 minutes of life. Subsequent examinations were performed at less than 24 hours of age. RESULTS: Chest radiograph before treatment showed no significant differences between the two groups, but significant improvement was noted in the surfactant treated group, in contrast to the control group. The most common chest radiographic finding after surfactant administration was uniform (n=15) or disproportionate (n=2) improvement of pulmonary aeration. Patent ductus arteriosus developed in three treated neonates and in four cases in the control group. Air leak occurred in three cases in the treated group and in five cases in the control group. In one treated patient pulmonary hemorrhage developed and intracranial hemorrhage occurred in three treated neonates and in four cases in the control group. Bronchopulmonary dysplasia was developed in 6 cases of treated group and 3 cases of control group. CONCLUSION: A chest radiograph is considered to be helpful in the evaluation of improvement and complications of HMD in infants treated with surfactant.
Bronchopulmonary Dysplasia ; Ductus Arteriosus, Patent ; Hemorrhage ; Humans ; Hyalin* ; Hyaline Membrane Disease* ; Infant ; Infant, Newborn ; Intracranial Hemorrhages ; Membranes ; Radiography, Thoracic ; Retrospective Studies

The surgical outcome of excimer laser photorefractive keratectomy(PRK) depends on the accuracy of ablation and the smoothness of the surface ablated. The purpose of this study was to investigate the clinical usefulness of a new eyeball fixation device(EK fixation device). First, the PRK was done on the cornea of New Zealand white rabbit (-8 D, 5.5 mm). The surface with the device was smoother compared to that without. Second, The PRK (-4 D, 6 mm)was done on the surface of the contact lens over the cornea of human volunteers. The ablation surface with the device was smoother than that without(0.20+/-0.04 micrometer vs. 0.34 +/-0.14 micrometer, p=0.028). The epithelial healing experiment in New Zealand white rabbit after myopic PRK (-8 D, 5.5 mm)showed more rapid wound healing in the fixation group (66.49+/-0.03 micrometer/hr vs 47.93+/-1.80 micrometer/hr, p=0.0001). In conclusion, the EK fixation device during the PRK procedures creates a smoother ablation surface and enhances corneal epithelial healing, thus may be a useful clinical device.
Cornea ; Healthy Volunteers ; Lasers, Excimer ; New Zealand ; Wound Healing

BACKGROUND: Successful resuscitation of the brain requires unimpaired blood recirculation. However, unfortunately there are several factors against the successful recirculation. No-reflow phenomenon, characterized by a lack of reperfusion after cerebral ischemia, is the most important pathogenic factor during the early period of spontaneous circulation(ROSC). This study addresses question that pentoxifylline(PTX) ameliorates no-reflow phenomenon after cardiac arrest. METHODS: Fourteen rats were divided three group ; Sham group(n=2), 12 minutes cardiac arrest group without PTX(group I, n=6), and 12 minutes cardiac arrest group pretreated with PTX(group II, n=6). Group II were premedicated by intravascular injection of 5mg/kg PTX into the external jugular vein before 5minutes of the arrest-induction. We induced cardiac arrest with endotracheal clamping and muscle relaxant. And then, resuscitation was initiated. Arterial blood samples were drawn at the femoral artery before 5 minutes of arrest-induction and at the 5 minutes after restoration of ROSC. Reperfusion of brain was visualized by injection of 0.3g/kg of 15% FITC-albumin at 5 minutes after restoration of ROSC, and the animals were decapitated 2 minutes later. The left hemisphere was fixed with 4% formalin, and coronal sections of 200um thickness at three different standard levels of the rat brain were investigated with fluorescence microscopy. Density of microvasular filling were identified and calculated. RESULTS: Our observation demonstrated that 1. There were no significant differences of blood pressures, heart rates, and results of blood gas analysis between group I and II during the prearrest steady state. 2. There were no significant differences of blood pressures, heart rates, and results of blood gas analysis between group Iand II at 5minutes after ROSC. 3. Group II premedicated with PTX, showed significant increased capillary refiling(0.310+/-0.035)than group I without PTX(0.181+/-0.040). CONCLUSIONS : The results showed that during the prearrest steady state, premedication of PTX ameliorated the no-reflow phenomenon in the rat model of the asphyxial arrest. Further experimental studies are required to focus on the effects of postarrest infused PTX, The neurologic outcome, and the clinical applications.
Animals ; Blood Gas Analysis ; Brain ; Brain Ischemia ; Capillaries ; Constriction ; Femoral Artery ; Formaldehyde ; Heart Arrest* ; Heart Arrest, Induced ; Heart Rate ; Jugular Veins ; Microscopy, Fluorescence ; Models, Animal ; No-Reflow Phenomenon* ; Pentoxifylline* ; Premedication ; Rats* ; Reperfusion ; Resuscitation

No abstract available.
Glucose* ; Humans* ; Hyperglycemia* ; Monocytes*

PURPOSE: The cortical bone thickness on the anterior region is important for achieving implant stability. The purpose of this study was to examine the thickness of the cortical and cancellous bones on the anterior region of the maxilla and mandible. MATERIALS AND METHODS: Twenty-five cadaver heads were used (16 male and 9 female; mean death age, 56.7 years). After the long axis of alveolar process was set up, it was measured in 5 levels starting from 2 mm below the cementoenamel junction (L1) at intervals of 3 mm. All data was analysed statistically by one-way ANOVA at the .05 significance level. RESULTS: The cortical bone thickness according to measurement levels in both the labial and lingual sides increased from L1 to L5, and the lingual side below L3 was significantly thicker than the labial side on the maxilla and mandible. In particular, the labial cortical bone thickness in the maxilla was the thinnest compared to the other regions. The cancellous bone thickness according to measurement levels increased from L1 to L5 on the maxilla, and on the mandible it was the thinnest at the middle level of the root. CONCLUSION: For implant placement on the anterior region, a careful evaluation and full knowledge on the thickness of the cortical and cancellous bone are necessary, therefore, these results may provide an anatomic guideline to clinicians.
Alveolar Process ; Axis, Cervical Vertebra ; Cadaver ; Head ; Humans ; Male ; Mandible ; Maxilla ; Tooth Cervix