• The Korean Journal of Nuclear Medicine
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• v.32 no.4
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• pp.365-373
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• 1998

Purpose: The conventional gamma camera is not ideal for scintimammography because of its large detector size (${\sim}500mm$ in width) causing high cost and low image quality. We are developing a small gamma camera dedicated for breast imaging. Materials and Methods: The small gamma camera system consists of a NaI (T1) crystal ($60 mm{\times}60 mm{\times}6 mm$) coupled with a Hamamatsu R3941 Position Sensitive Photomultiplier Tube (PSPMT), a resister chain circuit, preamplifiers, nuclear instrument modules, an analog to digital converter and a personal computer for control and display. The PSPMT was read out using a standard resistive charge division which multiplexes the 34 cross wire anode channels into 4 signals ($X^+,\;X^-,\;Y^+,\;Y^-$). Those signals were individually amplified by four preamplifiers and then, shaped and amplified by amplifiers. The signals were discriminated ana digitized via triggering signal and used to localize the position of an event by applying the Anger logic. Results: The intrinsic sensitivity of the system was approximately 8,000 counts/sec/${\mu}Ci$. High quality flood and hole mask images were obtained. Breast phantom containing $2{\sim}7 mm$ diameter spheres was successfully imaged with a parallel hole collimator The image displayed accurate size and activity distribution over the imaging field of view Conclusion: We have succesfully developed a small gamma camera using NaI(T1)-PSPMT and nuclear Instrument modules. The small gamma camera developed in this study might improve the diagnostic accuracy of scintimammography by optimally imaging the breast.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.383-389
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• 2017

This study aimed to select a yeast strain for optimizing the quality of distilled spirits. The brewing and distilling properties of 4 KFRI (Korea Food Research Institute) yeasts (Y88-4, Y98-4, Y172-6, Y192-4) and 2 industry yeasts (C1, C2) were compared. For investigating the possibility of using these strains on an industrial scale, diverse analytical methods were applied to assess parameters associated with distilled spirit quality such as alcohol content, pH, total acidity, and soluble solid content. After 11 days of fermentation, the alcohol strength obtained using six yeast strains reached 13.9-16.4% (v/v), while pH was 3.9-4.0, and total acid was 0.40-0.52%. To compare GC-MSD Volatile flavor components, all the distilled spirit samples were diluted to 20% (v/v) alcohol strength. Seven fusel alcohols, 26 esters, 2 acids, and 3 miscellaneous compounds were detected in the distilled spirits. Y88-4 had the most abundant volatile flavor component and scored the highest overall preference in sensory evaluation. After analyzing the various properties of yeasts, strain Y88-4 was finally selected as the best strain for producing distilled spirits.

• Journal of Mushroom
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• v.18 no.4
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• pp.357-364
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• 2020

The grade and price of Lentinula edodes largely differs in preference depending on the product area and seasonal factors. The product amount of autumn L. edodes was higher than that of spring L. edodes, but high quality, which is divided into "Hwago" is low in preference. Mostly, the autumn L. edodes is obtained as powder; hence, it is necessary to develop a processing method to utilize its flavor and aroma at an affordable price. Additionally, we estimated the content of 𝛽-glucan, ergosterol, vitamin D₂, reducing sugars, and free amino acids and evaluated the anti-inflammatory activity of saccharification powder of log-cultivated L. edodes. In the saccharification powders obtained via 7 min of UV irradiation of log-cultivated L. edodes, 𝛽-glucan and vitamin D₂ contents were found to be the highest, whereas ergosterol content was found to be the lowest. The content of reducing sugars ranged from 62.4 mg/L to 68.2 mg/L. The free amino acids were higher in these saccharification powders than in the control. Subsequently, RAW 264.7 cells were treated with different concentrations (10, 50, 100, 200, 300, and 500 ㎍/mL) of the saccharification powders of log-cultivated L. edodes obtained via different UV irradiation time applications. The cells showed good viability; the anti-inflammatory effect was found to be the highest at 7 min UV irradiation. Therefore, 7 min of UV irradiation was determined to be the optimum condition for manufacturing saccharification powders of log-cultivated L. edodes. Hence, saccharification powders of log-cultivated L. edodes may be used as a raw material for natural sweeteners, food additives, and in the food industry.

• Journal of Life Science
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• v.33 no.1
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• pp.15-24
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• 2023

To examine the antitumor effect of proso millet grains, whether proso millet grains exert apoptotic activity against human cancer cells was investigated. When the cytotoxicity of 80% ethanol (EtOH) extract of proso millet grains was tested against various cancer cells using MTT assay, more potent cytotoxicity was observed against human breast cancer MDA-MB-231 cells than against other cancer cells. When the EtOH extract was evaporated to dryness, dissolved in water, and then further fractionated by sequential extraction using four organic solvents (n-hexane, methylene chloride, ethyl acetate, and n-butanol), the BuOH fraction exhibited the highest cytotoxicity against MDA-MB-231 cells. Along with the cytotoxicity, TUNEL-positive apoptotic nucleosomal DNA fragmentation and several apoptotic responses including BAK/BAX activation, mitochondria membrane potential (Δψm) loss, mitochondrial cytochrome c release into the cytosol, activation of caspase-8/-9/-3, and degradation of poly (ADP-ribose) polymerase (PARP) were detected. However, human normal mammary epithelial MCF-10A cells exhibited a significantly lesser extent of sensitivity compared to malignant MDA-MB-231 cells. Irrespective of Fas-associated death domain (FADD)-deficiency or caspase-8-deficiency, human T acute lymphoblastic leukemia Jurkat cells displayed similar sensitivities to the cytotoxicity of BuOH fraction, excluding an involvement of extrinsic apoptotic mechanism in the apoptosis induction. These results demonstrate that the cytotoxicity of BuOH fraction from proso millet grains against human breast cancer MDA-MB-231 cells is attributable to intrinsic apoptotic cell death resulting from BAK/BAX activation, and subsequent mediation of mitochondrial damage-dependent activation of caspase cascade.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.1
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• pp.9-15
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• 2007

Purpose: Repetitive transcranial magnetic stimulation (rTMS) has recently been clinically applied in the treatment of drug resistant depressed patients. There are mixed findings about the efficacy of rTMS on depression. Furthermore, the influence of rTMS on the physiology of the brain is not clear. We prospectively evaluated changes of regional cerebral blood flow (rCBF) between pre- and post-rTMS treatment in patients with drug resistant depression. Materials and Methods: Twelve patients with drug-resistant depression (7 male, 5 female; age range: $19{\sim}52$ years; mean age: $29.3{\pm}9.3$ years) were given rTMS on right prefrontal lobe with low frequency (1 Hz) and on left prefrontal lobe with high frequency (20 Hz), with 20-minute-duration each day for 3 weeks. Tc-99m ECD brain perfusion SPECT was obtained before and after rTMS treatment. The changes of cerebral perfusion were analyzed using statistical parametric mapping (SPM; t=3.14, uncorrected p<0.01, voxel=100). Results: Following areas showed significant increase in rCBF after 3 weeks rTMS treatment: the cingulate gyrus, fusiform gyrus of right temporal lobe, precuneus, and left lateral globus pallidus. Significant decrement was noted in: the precental and middle frontal gyrus of right frontal lobe, and fusiform gyrus of left occipital lobe. Conclusion: Low-frequency rTMS on the right prefrontal cortex and high-frequency rTMS on the left prefrontal cortex for 3 weeks as an add-on regimen have increased and decreased rCBF in the specific brain regions in drug-resistant depressed patients. Further analyses correlating clinical characteristics and treatment paradigm with functional imaging data may be helpful in clarifying the pathophysiology of drug-resistant depressed patients.

• Tuberculosis and Respiratory Diseases
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• v.47 no.3
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• pp.321-330
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• 1999

Background : Early diagnosis and proper antibiotic treatment are very important in the management of ventilator-associated pneumonia (VAP) because of its high mortality. Bronchoscopy with a protected specimen brush (PSB) has been considered the standard method to isolate the causative organisms of VAP. However, this method burdens consumer economically to purchase a PSB. Another useful method for the diagnosis of VAP is quantitative cultures of aspirated specimens through bronchoscopic bronchoalveolar lavage (BAL), for which the infusion of more than 120 m1 of saline has been recommended for adequate sampling of a pulmonary segment. However, occasionally it leads to deterioration of the patient's condition. We studied the diagnostic efficacy of minibronchoalveolar lavage (miniBAL), which retrieves only 25 ml of BAL fluid, in the isolation of causative organisms of VAP. Methods: We included 38 consecutive patients (41 cases) suspected of having VAP on the basis of clinical evidence, who had received antibiotics before the bronchoscopy. The two diagnostic techniques of PSB and miniBAL, which were performed one after another at the same pulmonary segment, 'were compared prospectively. The cut-off values for quantitative cultures to define causative bacteria of VAP were more than $10^3$ colony-forming units (cfu)/ml for PSB and more than $10^4$ cfu/ml for BAL. Results: The amount of instilled normal saline required to retrieve 25 ml of BAL fluid was $93{\pm}32 ml$ (mean${\pm}$SD). The detection rate of causative agents was 46.3% (19/41) with PSB and 43.9% (18/41) with miniBAL. The concordance rate of PSB and miniBAL in the bacterial culture was 85.4% (35/41). Although arterial blood oxygen saturation dropped significantly (p<0.05) during ($92{\pm}10%$) and 10 min after ($95{\pm}3%$) miniBAL compared with the baseline ($97{\pm}3%$), all except 3 cases were within normal ranges. The significantly elevated heart rate during ($l25{\pm}24$/min, p<0.05) miniBAL compared with the baseline ($1l1{\pm}22$/min) recovered again in 10 min after ($111{\pm}26$/min) miniBAL. Transient hypotension was developed during the procedure in two cases. The procedure was stopped in one case due to atrial flutter. Conclusion: MiniBAL is a safe and effective technique to detect the causative organisms of VAP.