• Progress in Medical Physics
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• v.14 no.3
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• pp.203-210
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• 2003

PET (positron emission tomography) permits the investigation of physiological and biochemical processes in vivo. The accuracy of quantifying PET data is affected by its finite spatial resolution, which causes partial volume effects. In this study, we developed a method for partial volume correction using Hoffman phantom PET and MR data, and applied various FWHM (full width at half maximum) levels. We also applied this method to PET images of normal controls and tested for the possibility of clinical application. $^{18}$ F-PET Hoffman phantom images were co-registered to MR slices. The gray matter and white matter regions were then segmented into binary images. Each binary image was convolved by 4, 8, 12, 16 mm FWHM levels. These convolved images of gray and white matter were merged corresponding to the same level of FWHM. The original PET images were then divided by the convolved binary images voxel-by-voxel. These corrected PET images were multiplied by binary images. The corrected PET images were evaluated by analyzing regions of interests, which were drawn on the gray and white matter regions of the original MR image slices. We calculated the ratio of white to gray matter. We also applied this method to the PET images of normal controls. On analyzing the corrected PET images of Hoffman phantom, the ratios of the corrected images increased more than that of the uncorrected images. With the normal controls, the ratio of the corrected images increased more than that of the uncorrected images. The ratio increase of the corrected PET images was lower than that of the corrected phantom PET images. In conclusion, the method developed for partial volume correction in PET data may be clinically applied, although further study may be required for optimal correction.

• Journal of Plant Biotechnology
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• v.32 no.1
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• pp.37-44
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• 2005

Microspores were isolated from pepper (Capsicum annuum L.) anthers by using a micro-blender and cultured in modified NLN medium at $25^{\circ}C$. The influence of pretreatment period at $32^{\circ}C$, adding the 2-hydroxynicotinic acid to a pretreatment medium, and co-pretreatment anthers with microscopes on the induction of embryo were examined. Globular and torpedo embryos were observed from 3 weeks after culture. Embryo development was not synchronized within culture. After 4 weeks in culture, in addition to globular and torpedo embryos, cotyledonary embryos were observed. Normal cotylodonary embryos developed into plantlets when transferred to a solid hormone free B5 medium containing $2\%$ sucrose. Embryo yields were significantly higher after 1- and 2-day pretreatment at $32^{\circ}C$. However the development of embryo ceased at the globular or heart stage. In contrast, embryo yields were lower after 3- to 6-day pretreatment at $32^{\circ}C$ and embryo developed at the cotyledonary stage. After adding the 2-hydroxynicotinic acid to anther pretreatment solution, embryo yields were slightly increased. However most embryos occurred were at the globular or heart stage. Co-pretreatment of microspores with anthers was deleterious for embryo induction and development. AS far as we know, this is the first report of success in obtaining high frequency of embryogenesis and plantlets formation from isolated microspores of pepper. Although the culture conditions have to be optimized further, this promising microspore culture system can be used for genetic transformation, selection for dominant and recessive traits as well as for the production of homozygous doubled haploid plants.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.355-362
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• 2016

The phosphomannomutase/phosphoglucomutase gene (pmm/pgm) of Vibrio anguillarum (the causative agent of fish vibriosis) was cloned, and the open reading frame corresponded to a protein with 446 amino acids. The pmm/pgm gene showed a significant degree of sequence homology with the previously reported genes from V. mimicus, V. vulnificus, V. splendidus, and V. harveyi, with 92.3%, 91.4%, 89.9%, and 89.9% amino acid identity, respectively. By reverse transcriptase-polymerase chain reaction, we found that the pmm/pgm gene was upregulated under cold stress condition. The PMM/PGM protein is known to catalyze the interconversion between mannose-1-phosphate and mannose-6-phosphate or glucose-1-phosphate and glucose-6-phosphate, which are important intermediates for lipopolysaccharide (LPS) biosynthesis. To confirm the role of PMM/PGM in the LPS biosynthetic pathway, we constructed a knock out mutant by homologous recombination. The respective LPSs were isolated from the V. anguillarum wild-type and mutant strains, and changes were compared by subjecting them to sodium dodecyl sulfate polyacrylamide gel electrophoresis. Based on the different patterns of the LPSs, we expect the pmm/pgm gene to have an important role in LPS biosynthesis. The pmm/pgm-deficient mutant of V. anguillarum will contribute to further studies about the role of LPS in V. anguillarum pathogenesis.

• Journal of Environmental Impact Assessment
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• v.25 no.6
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• pp.502-513
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• 2016

In this study, heavy metal distributions in the tissues of feral pigeon (Columba livia) were characterized using samples collected from bio-monitoring sites (Hangang Park and Hampyeong Park) of the NESB (National Environmental Specimen Bank), Korea, in order to evaluate the feasibility of feral pigeons as an indicator for the environmental monitoring. Cadmium (Cd) was analyzed to be accumulated in kidneys at higher concentration than in the other tissues. Such trend can also be found in the reviews on the Cd accumulations of the 34 cases including 17 avian species which showed that 31 cases had the highest Cd concentrations in the kidney among tissues. However, lead (Pb) was found to be richest in the bones in this study. 17 cases out of 30 reviewed cases had the highest Pb concentration in bones, whereas other 10 cases showed the highest concentration in kidneys, and 3 cases in livers. Therefore, kidneys together with bones can be a main target organ to test cadmium exposure to different habitat environments depending on physiological traits of birds. Zinc (Zn) was found to be the highest concentration in the pigeon livers of Hangang Park, but not in the bones. In contrast, the 13 cases of 16 reviewed cases had the highest Zn concentration in bones, and the 3 cases in livers. In addition, the heavy metal distribution patterns in relations to the metal accumulation mechanisms (a competition between Pb and Ca, a function of methallothionein protein, and etc.) were discussed.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.247-257
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• 2014

Assessment for operator's dermal and inhalation exposure to acetamiprid during cultivation of water melon in greenhouse was carried out. For dermal exposure measurement, whole body dosimetry (WBD) was performed as the first trial in Korea. WBD consists of cotton/polyester outer clothes and cotton inner clothes. Hand exposure was measured by washing of nitrile gloves and hands while head exposure was monitored by face/neck wipe technique. Inhalation exposure was monitored with personal air sampling pumps and IOM sampler (glass fiber filter). Analytical limit of quantitation was 2.5 ng/mL. Good reproducibility (C.V < 8.7%), linearity ($R^2$ > 0.99) and recovery (70~119%) were obtained. Field recovery of acetamiprid was 77~95%. During mixing/loading, hand exposure of acetamiprid was about 10 times ($229.7{\mu}g$) more than that of application case ($20.9{\mu}g$). During application, total dermal exposure was $1207.4{\mu}g$. Exposure of lower legs was $1132.1{\mu}g$, which is 93.8% of the total dermal exposure. Inhalation exposure during mixing/loading and application was not detected. Margin of safety (MOS) was calculated for risk assessment using male Korean average body weight (70 kg) and acceptable operator exposure level ($124{\mu}g/kg/day$) to give 140, suggesting that health risk of operator during treatment of acetamiprid for water melon in greenhouse could be safe.

• Korean Journal of Psychosomatic Medicine
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• v.10 no.2
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• pp.154-165
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• 2002

Objectives : The purpose of this study was to identify characteristics of depression in cancer patients treated with chemotherapy. Methods : Subjects were 37 cancer inpatients of oncology in Yeungnam university hospital. BDI and ZDS were done and HDS was performed through semistructured interview. Results: 1) There were no significant differences of depression scale score according to sex, education, religion, marital status. 2) The mean scores of BDI, ZDS and HDS in 37 cancer patients were 18.27${\pm}$7.73, 36.51${\pm}$10.82, 15.14${\pm}$6.60, respectively. 3) HDS, ZDS scores were significantly higher in other cancer group receiving high dose chemotherapy. 4) Item score for depressed mood, diurnal variation(p<0.001), dissatisfaction(p<0.01), physical anxiety, decreased libido, sleep disturbance(p<0.05) were significantly higher in other cancer group than others. 5) Eight patients were diagnosed as having major depressive disorder, 11 as adjustment disorder, and 18 patients had no axis I diagnosis. 6) In major depressive disorder group, the score of the depressed mood item in ZDS was high (p<0.05). HDS item score for depressed mood, work difficulty, anxiey(p<0.001), psychomotor retardation(p<0.01) were significantly higher in major depressive disorder group. 7) In patients with adjustment disorder, ZDS item score of constipation(p<0.001), fatigue, anorexia (p<0.01), emptiness, sleep disturbance, dissatisfaction, weight loss(p<0.01) were high. HDS item score of hypochondriasis(p<0.01), agitation(p<0.01), fatigue, decreased libido(p<0.05) were significantly higher in adjustment disorder group. Conclusion : Some psychiatric disorders, such as adjustment disorder and major depressive disorder were common in the cancer patients in chemotherapy. Psychiatric intervention will increase compliance of cancer treatment and improve the quality of life. This study suggests that it would be important to consider the nature of somatic symptoms in diagnosing depression in cancer patients.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.201-205
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• 2005

The aim of publishing the Korean Pharmaceutical Codex is to update and set specification of essential drugs for humane health. In accordance with speedy development of new drugs and improvement of science and technology, the need of revision of drug specification through the ICH guidelines and discussions between regulatory agency and pharmaceutical industry for the quality assurance of safer and efficient drugs is getting higher. The first edition of Korean Pharmaceutical Codex was published in 1983. Now, the third revision of the Codex is prepared because of the revision of domestic and foreign Pharmacopeias, changes of drug control environment, improvement of science and technology and so on. The aim of 3th edition is to improve the quality of essential drugs through the setting of the required specifications and discussions between the regulatory agency and pharmaceutical industry.

• The Korean Journal of Malacology
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• v.32 no.1
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• pp.45-54
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• 2016

To evaluate the applicability of cellular energy allocation (CEA) in the bivalves as a biomarker for the assessment of environmental contamination, the energy contents and energy consumption in several tissues of the Manila clam, Ruditapes philippinarum were analyzed. The contents of lipid, glucose, protein and electron transport system (ETS) activity in the foot, siphons, gills, and body of R. philippinarum exposed to crude oil-spiked sediments were measured at 1, 2, 4, 7, 10 days after exposure. The reserved energy (energy available, EA) in the lipid, glucose and protein decreased as contamination level and exposure time increased. In contrast, the ETS activity (energy consumed, EC) showed the reverse tendency. The order of available energy contents were foot > siphons > gill > body. Significant differences in both EA and EC were found only at the highest contamination level (58.3 mg TPAHs/kg DW). EA decreased significantly in the foot and gill at 1 day, in the body at 2 and 7 days after exposure. EC increased significantly in the body at 4 days after exposure. CEA showed higher sensitivity to the contamination than EA or EC. Especially, CEA in the foot and body decreased significantly at lower ranges of contamination level (as low as 6.5 mg TPAHs/kg DW) during 1 to 7 days after exposure. The CEA is more useful than EA or EC alone for the assessment of sediment contamination at lower level that acute toxicity could not be detected. CEA analyses in the body of R. philippinarum after 4 days' exposure to contaminated sediments seem to be the most sensitive and reliable.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.2
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• pp.153-165
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• 2017

Objectives : Recent neuroimaging studies focus on dysfunctions in connectivity between cognitive circuits and emotional circuits: anterior cingulate cortex that connects dorsolateral orbitofrontal cortex and prefrontal cortex to limbic system. Previous studies on pediatric depression using DTI have reported decreased neural connectivity in several brain regions, including the amygdala, anterior cingulate cortex, superior longitudinal fasciculus. We compared the neural connectivity of psychotropic drug naïve adolescent patients with a first onset of major depressive episode with healthy controls using DTI. Methods : Adolescent psychotropic drug naïve patients(n=26, 10 men, 16 women; age range, 13-18 years) who visited the Korea University Guro Hospital and were diagnosed with first onset major depressive disorder were registered. Healthy controls(n=27, 5 males, 22 females; age range, 12-17 years) were recruited. Psychiatric interviews, complete psychometrics including IQ and HAM-D, MRI including diffusion weighted image acquisition were conducted prior to antidepressant administration to the patients. Fractional anisotropy(FA), radial, mean, and axial diffusivity were estimated using DTI. FMRIB Software Library-Tract Based Spatial Statistics was used for statistical analysis. Results : We did not observe any significant difference in whole brain analysis. However, ROI analysis on right superior longitudinal fasciculus resulted in 3 clusters with significant decrease of FA in patients group. Conclusions : The patients with adolescent major depressive disorder showed statistically significant FA decrease in the DTI-based structure compared with healthy control. Therefore we suppose DTI can be used as a bio-marker in psychotropic drug-naïve adolescent patients with first onset major depressive disorder.

• Clinical and Experimental Pediatrics
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• v.45 no.2
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• pp.199-207
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• 2002

Purpose : Since the successful application of total atrio-pulmonary connection(TAPC) to patients with various types of physiologic single ventricles in 1971, post-operative survival rates have reached more than 90%. However some patients have been shown to present with late complications such as right atrial thrombosis, atrial fibrillation and protein losing enteropathy eventually leading to re-operation to control the long-term complications. The aim of this study is to review the results of total cavo-pulmonary connection(TCPC) in cases with late complications after TAPC. Methods : Between Jan. 1995 and Dec. 2000, 6 patients(5 males and 1 female) underwent cardiac catheterization $11{\pm}3$ months after conversion of previous TAPC to TCPC. We compared the hemodynamic and morphologic parameters before and after TCPC and also assessed the clinical outcomes. The indications for TAPC were tricuspid atresia in 4 cases and complex double-outlet right ventricle with single ventricle physiology in 2 cases. Results : There was no peri-operative mortality and all patients were clinically and hemodynamically improved at a mean follow-up of 11 months(range : 4 to 13). However, protein losing enteropathy recurred in 2 patients; this was were successfully treated with subcutaneous administration of heparin. Right atrial pressure before TCPC was $18.0{\pm}3.6mmHg$, but baffle pressure, corresponding to right atrial pressure decreased to $14.8{\pm}3.6mmHg$ after TCPC. The size of the pulmonary arteries did not regress after TCPC. Conclusion : The conversion of TAPC to TCPC improves clinical and hemodynamic status by decreasing the right atrial pressure and by providing a laminar cavo-pulmonary flow which enhances the effective pulmonary circulation in the so-called Fontan circulation.