• Journal of radiological science and technology
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• v.31 no.3
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• pp.267-276
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• 2008

The 25 healthy male volunteers aged from 20 to 50years old have been employed in this study. 2D-PC MRA was performed to measure the velocity of the blood flow in the internal carotid artery and internal jugular veins using 3.0T MRI Whole body (signa VH/i GE). ECTRICKS-CEMRA was performed to evaluate the pattern of blood circulation from internal carotid artery to internal jugular vein. Using 2D-PC MRA, the cross-section of the 4th and 5th cervical discs was scanned with 24cm FOV. Then the speed of blood flow was measured for internal carotid artery and internal jugular vein when the subject wears a necktie tightly and no tie. The average of maximum velocity of internal carotid arteries without a necktie was 72.13cm/sec in the right side and 74.96cm/sec in the left side(average 73.54cm/sec in both sides) while the average of maximum velocity of internal jugular veins without a necktie was -34.45cm/sec in the right side and -24.99cm/sec in the left side (-29.72cm/sec in both sides). However, when wearing a necktie tightly, the average of maximum velocity of internal carotid arteries was 61.35cm/sec in the right side and 65.19cm/sec in the left side(average 63.27cm/sec in both sides) while the average of maximum velocity of internal jugular veins was -22.14cm/sec in the right side and -17.93cm/sec in the left side(-20.03cm/sec in both sides). With the necktie tightly knotted, the average blood flow speed of both internal carotid arteries slightly decreased to 86% (63.27/73.54cm/sec) compared to no tie case in which both internal jugularveins significantly went down to 67% (-20.03/-29.72 cm/sec). Thus it is suggested that wearing a necktie affects the circulation of internal jugular veins(33% decrease in blood flow speed) more significantly than that of internal carotid artery(14% decrease in blood flow speed). Without a necktie, ECTRICKS-CEMRA showed natural blood circulation patterns of internal carotid arteries and internal jugular veins without any disturbances or compressions. However, when wearing a necktie tightly, ECTRICKS-CEMRA showed severe compression onto both internal jugular veins in all 25 volunteers. In conclusion, the result of the study showed that the tightly worn necktie instantly presses more internal jugular veins than internal carotid arteries, thereby significantly reducing the blood flow speed and leading to the temporary occlusion. Thus, the defecation or washing the face under the tightly tied necktie situations can cause the unexpected and temporary compression or occlusion of the internal jugular veins, subsequently leading to the occurrences of the stroke due to the secondary intracranial venous hypertension.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.6
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• pp.302-308
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• 2006

Purpose: Although several neuroanatomical models of panic disorder have been proposed, little is known regarding the neurological mechanisms underlying cognitive-behavioral therapy (CBT) in patients with panic disorder. This study was performed to identify the brain structures that show changes of regnioal cerebral blood flow (rCBF) after CBT in patients with panic disorder. Materials and Methods: Seven patients who were diagnosed as panic disorder by DSM-IV were treated with CBT for 8 weeks and twelve healthy volunteers joined in this study. Serial $^{99m}Tc-ECD$ brain perfusion SPECT images were acquisited and PDSS-SR (Self-Report version of Panic Disorder Severity Scale) and ACQ (Agoraphobic Cognitive Question) scores were measured just before and after CBT in all patients. Data were analyzed using SPM2. Results: Subjective symptoms were improved, and PDSS-SR and ACQ scores were significantly reduced ($14.9{\pm}3.9\;vs.\;7.0{\pm}1.8$, p<0.05; $30.3{\pm}8.5\;vs.\;21.6{\pm}3.4$, p<0.05, respectively) after CBT in panic patients. Before CBT, a significant increase of rCBF was found in the cingulate gylus, thalamus, midbrain, both medial frontal and temporal lobes of the panic patients compared to the normal volunteers. After CBT, we observed a significant rCBF decrease in the left parahippocamus, right insula and cingulate gyrus, both frontal and temporal lobes, and a significant rCBF increase in both the occipital lobes, left insula, both frontal and left parietal lobes. Conclusion: These data suggested that CBT is effective for panic disorder and diminish the activity of the brain areas associated with fear in panic disorder.

• Investigative Magnetic Resonance Imaging
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• v.12 no.1
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• pp.33-39
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• 2008

Purpose : There is debate concerning the observation of metabolite changes on MRS at the designated cortex during some tasks. The purpose of this study is to assess the change of the lactate content at the motor cortex during hand-grasping tasks with performing real-time fMRI-guided fMRS. Materials and Methods : Seven healthy volunteers (23-28 years old) underwent realtime fMRI during right hand grasping tasks with using a 1.5 T system. After confirming the activating area, single voxel MRS was preformed at 1) the baseline, 2) during the task and 3) after the task on the activating cortex. The three consecutive spectra were compared for observing the changes of the lactate content by the tasks. The Cho/Cr, NAA/Cr and Lac/Cr ratios were calculated manually from those spectra. Results : MRS during the tasks revealed the lactate peaks at the 1.33 ppm resonance frequency with great conspicuity at the activated area, which was identified on the real-time fMRI. After the task scan, the lactate peaks completely disappeared and the spectra recovered to the values of the baseline scan in all volunteers. At baseline, during the task and after the task, the Cho/Cr ratios were 0.81, 0.76 and 0.77, respectively, and the NAA/Cr ratios were 1.68, 1.65 and 1.72, respectively, and the Lac/Cr ratios were 0.28, 0.41 and 0.30, respectively. During the task, Lac was significantly increased by 46%. Conclusion : We observed prominent lactate peaks on MRS during hand-grasping tasks at the activated area, as was shown on the real-time fMRI. We suggest that fMRS can be used as a sensitive tool for observing the metabolite changes of the functioning brain.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.542-550
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• 2003

Background : Synthetic glucocorticoids are widely used in many chronic inflammatory diseases because of their excellent anti-inflammatory activity. Enhancing the transcription of $I{\kappa}B$ and preventing activated NF-${\kappa}B$ from binding to ${\kappa}B$ sites are thought to be the underlying mechanisms. But these data are largely derived from in vitro studies using cell lines. In this study, after administrating a steroid to volunteers, we evaluated the effect on the NF-${\kappa}B$ system. Methods : Prednisolone(0.5mg/kg/d) was orally administered to 5 healthy volunteers for 7 days. Before and after the administration, we sampled their peripheral blood monocytes, and performed western blot analysis both with stimulation, using IL-$1{\beta}$, LPS, TNF, and without stimulation(baseline). We also performed EMSA after stimulation with LPS. Results : After ingestion of the steroid, baseline expressions of $I{\kappa}B{\alpha}$ were increased in two of the subjects, while suppressed degradations of $I{\kappa}B{\alpha}$ to stimulations were observed in all five. In addition, the binding capacity of NF-${\kappa}B$ after the administration was decreased. Conclusion : Steroid plays such roles as enhancing the transcription of $I{\kappa}B{\alpha}$, suppressing the DNA binding capacity of NF-${\kappa}B$, and suppressing the degradation of $I{\kappa}B{\alpha}$.

• Journal of Life Science
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• v.29 no.2
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• pp.265-271
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• 2019

In general, specific gravity (SG) and urinary creatinine (CR) have been used to adjust urinary cadmium (Cd) concentrations. However, the validity of correction methods has been controversial. We compared the two adjustments to evaluate associations between urinary Cd and various renal damage markers and to evaluate the relationship between urinary Cd concentration and renal disease markers, such as estimated glomerular filtration rate (eGFR), in a relatively large general population sample. Among the 1,086 volunteers who were enrolled in this study, 862 healthy volunteers who did not have kidney disease were included in the final analysis. Urinary Cd, malondialdehyde (MDA), and N-acetyl-${\beta}$-D-glucosaminidase (NAG) concentrations were measured, the creatinine-based eGFR was calculated, and the relationships between these markers were subsequently analyzed. This study showed the use of urinary Cd concentration adjusted with SG rather than with urinary creatinine may be appropriate in studies evaluating renal function based on Cd exposure. Urinary Cd concentration adjusted with SG had a positive correlation with urinary MDA levels and a negative correlation with eGFR. This relationship was relatively stronger in women than in men. This study showed that urinary Cd level was associated with decreased eGFR in the general population, and oxidative stress was likely to act as an intermediator in this process. These results suggest that eGFR can be a very good indicator of kidney damage caused by Cd exposure in the general population.

• IMMUNE NETWORK
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• v.4 no.1
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• pp.16-22
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• 2004

Background: To develop a novel treatment strategy for hepatitis B virus infection, a major cause of liver chirosis and cancer, we aimed to make human monoclonal antibodies inhibiting RNase H activity of P protein playing in important role in HBV replication. In this regard, phage display technology was employed and demonstrated as an efficient cloning method for human monoclonal antibody. So this study analysed the usability of human monoclonal antibody as protein based gene therapy. Methods: RNase H of HBV was expressed as fusion protein with maltose binding protein and purified with amylose resin column. Single chain Fv (scFv) phage antibody library was constructed by PCR cloning using total RNAs of PBMC from 50 healthy volunteers. Binders to RNase H were selected with BIAcore 2000 from the constructed library, and purified as soluble antibody fragment. The affinity and sequences of selected antibody fragments were analyzed with BIAcore and ABI automatic sequencer, respectively. And finally RNase H activity inhibiting assay was carried out. Results: Recombinant RNase H expressed in E. coli exhibited an proper enzyme activity. Naive library of $4.46{\times}10^9cfu$ was screened by BIAcore 2000. Two clones, RN41 and RN56, showed affinity of $4.5{\times}10^{-7}M$ and $1.9{\times}10^{-7}M$, respectively. But RNase H inhibiting activity of RN41 was higher than that of RN56. Conclusion: We cloned human monoclonal antibodies inhibiting RNase H activity of P protein of HBV. These antibodies can be expected to be a good candidate for protein-based antiviral therapy by preventing a replication of HBV if they can be expressed intracellularly in HBV-infected hepatocytes.

• Journal of Pharmaceutical Investigation
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• v.38 no.4
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• pp.261-267
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• 2008

The aim of the present study was to evaluate the bioequivalence of two gabapentin preparations. We used Neurontin tablet 800 mg (Pfizer Korea Inc.) as a reference drug for bioequivalence of Gabalep tablet 800 mg (Chong Kun Dang Pharmaceutical Co., Korea), and performed this whole study according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty five healthy male volunteers were administered with each drug in a randomized $2{\times}2$ cross-over study with one week washout interval. After drug administration, blood was taken at predetermined time intervals ($0{\sim}24$ hours) and the concentrations of gabapentin in serum were determined using an high performance liquid chromatography-tandem mass spectrometer (LC-MS/MS) employing electrospray ionization technique and operating in multiple reaction mornitoring (MRM). The analytical method was validated in specificity, accuracy, precision and linearity. The phar-macokinetic parameters such as AUCt and Cmax were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed AUCt and Cmax. $Mean{\pm}SD$. of AUCt and Cmax value for reference drug and test drug were $29.94{\pm}9.23\;({\mu}g/mL{\cdot}hr)$ and $3.12{\pm}1.11\;({\mu}g/mL{\cdot}hr)$, and $31.48{\pm}9.77\;({\mu}g/mL{\cdot}hr)$ and $3.15{\pm}1.03\;({\mu}g/mL)$, respectively. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) for AUCt and Cmax, respectively. These results indicate that Gabalep tablet 800 mg is bioequivalent to Neurontin tablet 800 mg.

• Annals of Clinical Neurophysiology
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• v.12 no.2
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• pp.61-65
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• 2010

Background: Orthostatic hypotension (OH) refers to a fall in systolic blood pressure (BP) of 20 mmHg or more, or in diastolic BP of 10 mm Hg or more within 3 minutes of standing up. The head-up tilt test (HUT) is the most useful, but potentially invasive test for the diagnosis of OH. The purpose of this study was to identify the usefulness of spontaneous baroreflex sensitivity (sBRS). Methods: Ninety one patients with orthostatic intolerance, in whom the HUT data were available, were included in the study. Patients were classified into HUT-positive (group I) and HUT-negative (group II) group. Twenty five healthy volunteers served as normal controls, and were designated as group III. In all subjects, beat-to-beat BP and heart rate were recorded using BeatScope 1.1a. We collected the 50 sBRS data in each patient in a supine position. The average value of one to ten of 50 sBRS data was defined as sBRS10, one to twenty as sBRS20, one to thirty as sBRS 30, one to forty as sBRS 40, and one to fifty as sBRS 50. Differences in sBRS10 and sBRS50 levels were statistically analyzed and compared between groups I, II, and III. Results: No significant difference in the sBRS50 level was found between Groups II and III. sBRS50 was significantly lower in Group I than in Groups II and III (p<0.05), and the same pattern of differences was observed for sBRS40, sBRS30, sBRS20, and sBRS10. Conclusions: Patients with OH showed significantly lower sBRS levels than HUT-negative patients or normal controls. Our study implies that a supine-position sBRS would provide additional diagnostic information for OH.

• Investigative Magnetic Resonance Imaging
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• v.13 no.2
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• pp.137-145
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• 2009

Purpose : To compare 12 and 32-element surface coil arrays for highly accelerated coronary magnetic resonance angiography (MRA) using parallel imaging. Materials and Methods : Steady state free precession coronary MRA was performed in 5 healthy volunteers at 1.5 T whole body MR scanner using both 12 and 32-element surface coil arrays. Left anterior descending and right coronary artery data sets were acquired for each volunteer. Data sets were sub-sampled for parallel imaging using reduction factors from 1 to 6. Mean geometry factor (g-factor), maximum g-factor, and artifact level were calculated for each of the two coil arrays. Results : Over all reduction factors, the mean and maximum g-factors and artifact level were significantly reduced using the 32-element array compared to the 12element array (P << 0.1). The mean g-factor was sensitive to the imaging orientations of coronary arteries while the maximum g-factor and artifact level were independent of orientation. Conclusion : The 32-element surface coil array significantly improves artifact and noise suppression for highly accelerated coronary MRA using parallel imaging. The increased acceleration factors made feasible with the 32-element array offer the potential to enhance spatial resolution or increase volumetric coverage for 3D coronary MRA.

• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.141-151
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• 1999

To evaluate the effect of cetylpyridinium chloride in a powder form when used concomitantly with a commercial flouride containing tooth paste on inhibition of plaque formation, on gingivitis, and on irritation of oral mucosa, a double--blind, randomized parallel study was set up. Cetylpyridinium chloride was incorporated into a ligh brown colored powder with menthol added for scent. There were no diffemces between the active agent and the placebo which did not contain cetylpyridinium chloride in appearance, color, smell, taste, or dispenser. 98 healthy volunteers were assigned to one of two groups: brushing 3 times a day with flouride toothpaste and cetylpyridinium chloride powder, or brushing 3 times a day with flouride toothpaste and placebo. Before the test period, the subjects received through tooth cleaning and polishing. At basteline, GI, PI, BOP, and GCF of the Ramfjord teeth were measured in the experimental and placebo groups including 58 and 42 subjects repectively, After 4 weeks, GI, PI, BOP, GCF, compliance, irritation of the oral mucosa(redness, pus drainage, edema) and adverse reactions were measured. The PI, GI, and BOP of the experimental group recorded at baseline are 0.19${\pm}$0.19, 0.42${\pm}$0.31, and 0.08${\pm}$0.15. These scores showed significant decrease after 4 weeks of test period(0.11${\pm}$0.15, 0.22${\pm}$0.24, 0.02${\pm}$0.09 repectively at the end of the study) and inhibition of plaque accumulation and resolution of gingival inflammation could be observed. GCF shoed slight increase but this was not statistically different. Comparison of changes in measured scores of control and experimental groupshow GI, PI of the test indices have decreased. Test group showed significantly greater decrease in gingivitis and plaque accumulation after 4 weeks. GCF and BOP also showed greater decrease thant the control group but this difference was not statistically significant. At no time of the study period did any of the subjects show signs of irritation of the oral mucosa or adverse reactions. Following conclusions could be obtained from this study. The combined use of cetl powder and flouride toothpaste showed greater inhibition of plaque accumulation and greater decrease of gingivitis than use of flouride toothpaste with placebo agent.