• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.193-210
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• 1971

Reviewed biosynthetic pathways in green leaves of thiamine, riboflavin and folate as disclosed by the authors, and the regulatory systems operating on their biosynthesis and biodegradation as revealed since a potent inhibitory activity of ATP was found for the phosphatase reactions in 1965. Physiological roles of ascorbic acid in plant were evidenced by its higher content in green and flower leaves; the content in persimmon leaves for example was found ten or more times of that in citrus fruits. A close relationship existing between basic and development researches was illustrated by examples chosen from the author's researches. Examples cited were as follows; basic researches on vitamins were extended to the creation of thiamine enriched rice, to the growth promotion of rice plant by foliar application of thiamine, and to the use of ascorbic acid to prevent the appearance of beer cloudness; histological and biochemical studies on protein bodies in rice endosperm turned out amino acid enriched rice; techniques acquired in the studies on catalase were successfully employed for the utilization of single cell protein (MIPRON) for human food; conception of hybernation was led up to under-water or under-ground storage of cereal grains.

• The Korea Journal of Herbology
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• v.20 no.3
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• pp.9-18
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• 2005

Objectives : The purpose of this study is to investigate characteristics of cell morphology of two different agar woods (Aquilaria agallocha Roxburgh (AAR) and imitative agar wood (IAW)) using microscopic techniques. Methods : Both light and scanning electron microscopes were used to observe morphological and histological features of the cell of agar woods collected from commercial products in the market. Results : The cell morphology and tissue arrangements of AAR depending on either the adsorption of resin into vessels or no adsorption of resin were observed to compare these features with those of both IAW and Aquilaria sinensis Gilb (ASG). Conclusions : As a result, the vessels of AAR with the resin adsorption was packed with lots of yellow-brownish materials, which were quite different from those of IAW and ASG. The cell walls were thick, and had well-developed traumatic parenchyma tissues with squared cells of the same height and width, which appeared as a clump of small grains packed.

• The Korean Journal of Gastroenterology
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• v.72 no.6
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• pp.277-280
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• 2018

Although small bowel the mainly occupies the most part of the gastrointestinal tract, small intestine tumors are rare, insidious in clinical presentation, and frequently represent a diagnostic and management challenge. Small bowel tumors are generally classified as epithelial, mesenchymal, lymphoproliferative, or metastatic. Familial adenomatous polyposis and Peutz-Jeghers syndrome are the most common inherited intestinal polyposis syndromes. Until the advent of capsule endoscopy (CE) and device-assisted enteroscopy (DAE) coupled with the advances in radiology, physicians had limited diagnostic examination for small bowel examination. CE and new radiologic imaging techniques have made it easier to detect small bowel tumors. DAE allows more diagnosis and deeper reach in small intestine. CT enteroclysis/CT enterography (CTE) provides information about adjacent organs as well as pictures of the intestinal lumen side. Compared to CTE, Magnetic resonance enteroclysis/enterography provides the advantage of soft tissue contrast and multiplane imaging without radiation exposure. Treatment and prognosis are tailored to each histological subtype of tumors.

• Journal of Plant Biotechnology
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• v.50
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• pp.255-266
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• 2023

Hyperhydricity is a physiological anomaly that significantly affects the growth and proliferation rate of crops cultivated by tissue culture techniques. To better understand the mechanisms that govern hyperhydricity incidence, we examined the effects of several media components, particularly cytokinin and gelling agents. These elements were found to be influential in both in vitro propagation and the development of hyperhydricity. Our study revealed that Arabidopsis thaliana seedlings had a greater manifestation of hyperhydricity symptoms when exposed to high cytokinin concentrations compared with the control. The presence of gelrite led to the manifestation of hyperhydric symptoms by elevated water build-up in the apoplast. The phenomenon of stomata closure was observed in the hyperhydric leaves, resulting in an increased ability to retain water and a decrease in the transpiration rates when compared to their respective control leaves. Additionally, histological examinations of the cross sections of hyperhydric leaves revealed an irregular cellular arrangement and large intercellular spaces. Furthermore, hyperhydric seedlings displayed impaired cuticular development in comparison to their normal seedlings.

• Korean Journal of Biological Psychiatry
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• v.5 no.1
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• pp.3-16
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• 1998

The neurophysiological study has been widely used in search of the relationship between brain and behavior. The basic techniques for the animal experiments of this kind such as stereotaxic techniques, lesioning methods, the methods of electrical stimulation and recording, and confirmation of histological location were briefly reviewed. Nevertheless, the importance of complementary neurochemical, neuroanatomical and behavioral studies can not be neglected.

• Plant Biotechnology Reports
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• v.5 no.2
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• pp.187-195
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• 2011

The gesneriaceous perennial plant Titanotrichum oldhamii has beautiful foliage and attractive bright yellow flowers. However, breeding of T. oldhamii by conventional sexual hybridization may be difficult because sexual reproduction of this species is very rare. In the present study, plant regeneration systems via both direct and indirect formation of adventitious shoots from leaf explants were established as the first step toward breeding T. oldhamii by using biotechnological techniques. Adventitious shoots were formed efficiently on medium containing $0.1mg\;l^{-1}$ benzyladenine. Histological observation showed that shoot formation on this medium occurred directly from leaf epidermal cells without callus formation. On the other hand, leaf explants formed calluses on medium containing $0.1mg\;l^{-1}$ 2,4-dichlorophenoxyacetic acid. The calluses could be maintained by monthly subculturing to fresh medium of the same composition. When the calluses were transferred to plant growth regulator-free medium, they formed adventitious shoots. Directly and indirectly formed shoots rooted well on medium containing $0.1mg\;l^{-1}$ indole-3-butyric acid. Plantlets thus obtained were successfully acclimatized and grew vigorously in the greenhouse. Flow cytometry analysis indicated that no variation in the ploidy level was observed in plants regenerated via direct shoot formation, whereas chromosome doubling occurred in several plants regenerated via indirect shoot formation. Regenerated plants with the same ploidy level as the mother plants showed almost the same phenotype as the mother plants, whereas chromosome-doubled plants showed apparent morphological alterations: they had small and crispate flowers, and round and deep green leaves.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.334-343
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• 2016

Background: Progressed tissue culture techniques have allowed us to easily obtain mass products of tissue-cultured mountain ginseng over 100 yr old (TCMG-100). We investigated the effects of TCMG-100 extract on erectile function using in vitro and in vivo studies. Methods: To examine the relaxation effects and mechanisms of action of TCMG-100 on rabbit cavernosal strips evaluated in an organ bath. To investigate the long-term treatment effect of TCMG-100, 8-wk administration was performed. After administration of TCMG-100, intracavernosal pressure, cyclic guanosine monophosphate and nitric oxide (NO) levels of cavernosal tissue, serum testosterone level, histological observation of collagen fiber, endothelium, smooth muscle cell, and transforming growth factor-${\beta}1$ were investigated. Results: TCMG-100 extract displayed dose-dependent relaxation effects on precontracted rabbit corporal smooth muscle. The TCMG-100-induced relaxation was significantly reduced by removing the endothelium, and treatment with an NO synthase inhibitor or NO scavenger. Eight weeks of TCMG-100 administration increased intracavernosal pressure in a rat model. The levels of cyclic guanosine monophosphate and NO in the corpus callosum and serum testosterone level were also increased by TCMG-100 treatment. Furthermore, histological evaluation of collagen, smooth muscle, and endothelium showed increases in endothelium and smooth muscle, and a decrease in transforming growth factor-${\beta}1$ expression. Conclusion: These relaxation effects on corporal smooth muscle and increased erectile function suggest that TCMG-100 might be used as an alternative herbal medicine to improve erectile function.

• Journal of Periodontal and Implant Science
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• v.50 no.6
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• pp.418-434
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• 2020

Purpose: The purpose of the present study was to evaluate the effect of silica-calcium phosphate composite (SCPC) granules on bone regeneration in extraction sockets. Methods: Ten patients were selected for a split-model study. In each patient, bone healing in SCPC-grafted and control ungrafted sockets was analyzed through clinical, radiographic, histomorphometric, and immunohistochemical assessments 6 months postoperatively. Results: A radiographic assessment using cone-beam computed tomography showed minimal ridge dimension changes in SCPC-grafted sockets, with 0.39 mm and 1.79 mm decreases in height and width, respectively. Core bone biopsy samples were obtained 6 months post-extraction during implant placement and analyzed. The average percent areas occupied by mature bone, woven bone, and remnant particles in the SCPC-grafted sockets were 41.3%±12%, 20.1%±9.5%, and 5.3%±4.4%, respectively. The percent areas of mature bone and woven bone formed in the control ungrafted sockets at the same time point were 31%±14% and 24.1%±9.4%, respectively. Histochemical and immunohistochemical analyses showed dense mineralized bundles of type I collagen with high osteopontin expression intensity in the grafted sockets. The newly formed bone was well vascularized, with numerous active osteoblasts, Haversian systems, and osteocytes indicating maturation. In contrast, the new bone in the control ungrafted sockets was immature, rich in type III collagen, and had a low osteocyte density. Conclusions: The resorption of SCPC granules in 6 months was coordinated with better new bone formation than was observed in untreated sockets. SCPC is a resorbable bone graft material that enhances bone formation and maturation through its stimulatory effect on bone cell function.

• Journal of Periodontal and Implant Science
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• v.40 no.1
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• pp.3-10
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• 2010

Purpose: Periodontal regenerative therapies for defects created by severe periodontitis are mainly focused on bone regeneration. Although cementum regeneration needs to be better understood, it is believed to play an important role in periodontal regeneration. The first step toward a full understanding of cementum regeneration is to compare repaired cementum to pristine cementum. This study, which used histological techniques, was designed to focus on cementum regeneration and to compare pristine cementum to repaired cementum after surgical procedures with 8 and 24 week healing periods in a canine model. Methods: Buccal and lingual mucoperiosteal flaps of 10 beagle dogs were surgically reflected to create critical-sized defects. Intrabony one-wall defects, of which dimension is 4 mm width and 5 mm depth, were made at the distal aspect of mandibular second premolars and the mesial aspect of mandibular fourth premolars in the right and left jaw quadrants. Animals were sacrificed after 8 and 24 weeks post-surgery for histological specimen preparation and histometric analysis. Results: The repaired cementum was composed mostly of acellular cementum and cellular mixed fiber cementum and was thicker in the apical area than in the coronal area. The acellular cementum of the supracrestal area appeared to be amorphous. The newly formed cellular cementum was partially detached from the underlying circumpulpal dentin, which implied a weak attachment between new cementum and dentin, and this split was observed to a lesser extent in the 24 week group than in the 8 week group. The vertical height of the repaired cementum was greater in the 24 week group than in the 8 week group. Conclusions: Within the limitations of this study, we can conclude that repaired cementum after root planing was mainly acellular cementum and cementum tissue that matured to a shape similar to pristine cementum as the healing progressed from 8 to 24 weeks.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.100-107
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• 2002

Purpose : The aim of this retrospective study was to assess the treatment results of 30 patients with pineal region tumors who were underwent radiation therapy under the diagnosis by either CT or MRI. There was no histological verification. We analyzed the prognostic factors that have a significant effect on the overall survival (OS) and disease free survival (DFS) rates. Materials and Methods : A total 30 patients with pineal region tumors were treated between March 1983 and August 1995. After a trial radiation therapy of $20\~30\;Gy/2\~3$ weeks, the patients were evaluated for their clinical response and radiological response by either CT or MRI and the final treatment direction was then decided. According to their response to the trial radiation therapy and the involved site, radiation treatment was given in various fields i.e., local, ventricle, whole brain and craniospinal field. The radiation dose ranged from 40.8 to 59.4 Gy (Median 50.4 Gy). The median follow up was 36.5 months $(4\~172\;months)$. Results : An improvement or stability in the clinical symptoms was observed in 28 patients $(93.3\%)$ after the trial RT. Nineteen patients $(63.3\%)$ showed a partial or complete response by CT or MRI. The two-year and five-year survival rates of the patients were $66.7\%$ and $55.1\%$, respectively. No significant difference in the survival rates according to the degree of the radiological response was abserved after the trial RT. The results of univariate analysis showed that age, the primary site, the performance status $(KPS\geq70)$, the degree of response after completing RT and the RT field were significant prognostic factors affecting the survival and disease free survival rates (p<0.05). Conclusion : The clinical and histological characteristics of pineal region tumors are quite complex and diverse. Therefore, it is difficult to predict the histological diagnosis and the possibility of radiocurability only with the initial response to RT. We think that the development of less invasive histological diagnostic techniques and tailored treatment to the histological type of each tumor are needed.