• Title/Summary/Keyword: lamellar

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The Study of Bone Formation around Titanium Implants Placed in Adrenalectomized Rat's Tibia (부신 제거 백서에 티타늄 임플랜트 매식후 주위 골형성에 관한 연구)

  • Choi, Kab-Lim;Kim, Jong-Ryoul;Park, Bong-Soo;Sung, Iel-Yong
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.22 no.3
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    • pp.274-287
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    • 2000
  • The use of dental implants has increased tremendously in recent years and is expected to increase even more in the future. The successful outcome of any implant procedure is surely dependent on interrelationship of the various components of an equation that includes biocompatibility of implant material, macroscopic and microscopic nature of the implant surface, the status of implant bed, surgical technique, undisturbed healing phase and subsequent prosthetic design and long-term loading phase. The purpose of this study was to clarify the effects of adrenalectomy on the osseointegration of pure titanium implants. Seventy rats, 11 weeks of age, were divided into two groups : an adrenalectomized group and a control group. Titanium screw implant(diameter, 2.0mm; length, 3.5mm) was placed into left tibia of 70 rats, 35 in control group and 35 in the experimental group. The rats were sacrificed at different time interval (1, 2, 3, 4, 6, 8, and 12 weeks after implantation) for histopathologic observation, histomorphometric analysis and immunohistochemistry with fibronectin and CD44 antibody. The results obtained from this study were as follows: 1. Histopathogically, findings, newly formed bone was seen at 3 weeks control group and became lamellar bone at 12 weeks. At 6 weeks, lipocytes were observed in bone marrow space. Thickness of regenerated trabecular bone increased till 6 weeks after then, that decreased gradually. 2. By histomorphometric analysis, marrow bone density and contact ratio of marrow bone to implant decreased significantly from 8 to 12 weeks in experimental group compared to control group and also total bone to implant contact ratio decreased significantly from 4 to 12 weeks in experimental group compared to control group. 3. Fibronectin immunoreactivity was very strong at 3 and 4 weeks control group. And after that reduced gradually. But it was continuously strong from 1 to 12 weeks experimental group. 4. CD44 immunoreactivity was very strong in the newly formed osteoblasts at 3 and 4 weeks control group. But it reacted minimally later. However, it reacted continuously strong from 3 to 12 weeks experimental group. From these results, bone to implant contact ratio decreased gradually from 4 weeks in adrenalectomized group compared to control group. CD44 and fibronectin immunoreactivities were strong at all times in adrenalectomized rats. Therefore, it could be stated that immature bone remained continuously for a long time and not readily proceeded into mature status.

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Micromorphology and Chemical Composition of a Sialolith in the Submandibular Gland Duct (악하선 내 타석의 미세형상 및 화학적 조성)

  • Im, Yeong-Gwan;Song, Ho-Jun;Kim, Byung-Gook
    • Journal of Oral Medicine and Pain
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    • v.36 no.3
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    • pp.161-167
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    • 2011
  • Sialolith is one of the most common pathologic conditions found in the salivary glands. The mechanisms responsible for the formation of sialoliths have not been elucidated so far. In this article, the chemical composition and micromorphology of a sialolith of a 58-year old female patient suffering from chronic sialoadenitis of the submandibular gland was analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). In a SEM evaluation, the highly mineralized amorphous core surrounded by lamellar and concentric structures was revealed, however no foreign body, organic material, or signs of microorganism were observed in the core of the sialolith. EDX analysis showed the central core was composed of only Ca, O and P, and that a high level of C was detected near the central area as well. These results indicated that the inorganic composition of the sialolith was hydroxyapatite crystals, and that inorganic and organic substances existed around the central cores. This study suggests that the sialolith was composed mainly of hydroxyapatite crystals and the formation of the nucleus of the sialolith in the submandibular gland duct was secondary to sialadenitis, which favors the growth of an inorganic crystalline nucleus.

BIOMECHANICAL EVALUATION ON BONE REGENERATION IN MANDIBULAR DISTRACTION OSTEOGENESIS COMBINED WITH COMPRESSION STIMULATION (하악골 신장술에서 압축자극을 통한 골 재생방식에 대한 생체 역학적 평가)

  • Heo, June;Kim, Uk-Kyu;Hwang, Dae-Seok;Kim, Yong-Deok;Shin, Sang-Hun;Chung, In-Kyo;Kim, Cheol-Hun;Yun, Seok-Young
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.5
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    • pp.470-478
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    • 2007
  • The purpose of this study was to investigate the clinical, biomechanical, and histologic changes in new distraction osteogenesis(DO) technique combined with a compression stimulation in accordance to different compression-distraction force ratio. 23 adult male rabbits underwent open-osteotomy at the mandibular body area and a external distraction device was applied. In the control group of 8 rabbits, only a 8 mm of distraction was performed by conventional DO technique. In an experimental group of 15 rabbits, a distraction followed by a compression force was performed according to the ratio of compression-distraction suggested by authors. The rate of experimental group I was set up as a 2 mm compression versus 10 mm distraction and the rate of experimental group II was set up as a 3 mm compression versus 11 mm distraction. All the rabbits were sacrificed for a gross finding, biomechanical, histomorphometric and histologic findings at the time of 55 days from the operation day. The results were as follows: 1. On the gross findings, because all rabbits had a sufficient healing time, every distracted new bone had good bone quality and we could not find any difference among all three groups. 2. In the histologic findings, rapid bone maturation(wide lamellar bone formation in the cancellous and cortical bone areas) was observed in two experimental groups compared to the control group. 3. On the bone density tests, the experimental group II showed higher bone density than the other experimental group and control group(control group-$0,2906g/cm^2$, experimental group I-$0.2961g/cm^2$, experimental group II-$0.3328g/cm^2$). 4. On the biomechanical tests, the experimental group II had significantly higher bone microhardness than the other experimental group and control group(control group-252.7 MPa, experimental group I-263.5 MPa, experimental group II-426.0 MPa). 5. On the microhardness tests, when we compared the hardness ratio of distracted bone versus normal bone, we could find experimental group II had significantly higher hardness ratio than the other experimental group and control group(control group-0.47, experimental group I-0.575, experimental group II-0.80). From this study, we could deduce that the modified distraction osteogenesis method with a compression stimulation might improve the quality of bone regeneration and shorten the consolidation period in comparison with conventional distraction osteogenesis techniques.

Synthesis of Novel Pseudo-ceramide and Its Properties (신규 유사세라마이드의 합성과 그 특성)

  • Kim, Jin-Guk;Kim, Kyoung-Tae;Park, Sun-Hee;Lee, Bang-Yong;Kim, Ki-Ho;Kim, Young-Heui
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.1
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    • pp.43-50
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    • 2008
  • Ceramides, a constituent of stratum corneum lipids, play a crucial role in the formation and maintenance of the epidermal permeability barrier. As in many other skin disorders, atopic dermatitis and psoriasis show decrease and transformation of the ceramides. The application of ceramide has been demonstrated to be efficient in the repair of these skin disorders. Nevertheless, natural ceramides are still too expensive and small in quantity to be used as a cosmetic ingredient. Although a lot of pseudo-ceramides have been developed and on the market until now, those pseudo-ceramides did not fully meet the consumer's needs, therefore, there is still a demand for a novel pseudo-ceramides. We synthesized a novel pseudo-ceramide BPC-16 from 2-(2-amino-ethylamino)-ethanol(AEEA), which was characterized by structures having both amide bonds and hydroxyl groups as hydrophilic units, as well as two long alkyl chains. We formulated emulsion with BPC-16, cholesterol, stearic acid, and other components to make an emulsion. These emulsion showed a typical optical anisotropy on cross-polarized microscopy. This 'Maltese cross' appearance is a characteristic figure observed in concentric lamellar emulsion under cross-polarized microscopy. In cytotoxicity assay using MTT in monolayer and three dimension(3D) cell culture, a BPC-16 showed only negligible cytotoxicity up to the effective concentration for barrier repair and moisturization(less than 10 mM). In the measurement of TEWL, this BPC-16 showed significant recovery of water-retaining properties when it was topically applied to either SDS-induced dry skin or normal skin compared to that of base cream. This novel pseudo-ceramide BPC-16 showed as effective in skin barrier repair and moisturization as natural ceramides.

Studies on the Fine Structures of Mouse Oocyte Whose Maturation has been suppressed in Vitro by Dibutyryl Cyclic AMP (Dibutyryl Cyclic AMP에 의해 成熟이 抑制된 Mouse 卵子의 微細構造에 관한 硏究)

  • 崔林淳
    • The Korean Journal of Zoology
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    • v.18 no.2
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    • pp.87-101
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    • 1975
  • Electron microscopic studies on the ultrastructure of the mouse oocyte were made to investigate the inhibition of germinal vesicle breakdown by dibutyryl cAMP. The nuclear membrane of the dibutyryl cAMP-treated oocyte is characterized by a decreased degree of folding, maintains the normal double membrane structure, and shows an increased occurrence of the nuclear pore. It is suggested that these may be related to the suppression of the maturation of oocytes at the germinal vesicle. Mitochondria in the control cell were shown to be spread evenly throughout the cytoplasm and structurally underdeveloped or transitionary having little cristae development. On the contrary, mitochondria in the treated oocyte were found to be localized mainly around the nucleus and to show a greater extent of cristae development. The oocyte treated with dibutyryl cAMP appears to have fewer and structurally simpler lysosomes as compared to the control. The Golgi complex in the control oocyte exhibits the typical granular and lamellar structure, whereas that in the treated cell is poorly developed. Many multivesicular bodies, tonofilaments, and free ribosomes were observed in the control as well as in treated cells. The microvilli become structurally irregular, and a development of the perivitelline space is apparent in the treated oocyte. It is concluded that there is no basic difference in the ultrastructure between the oocytes treated with dibutyryl cAMP for 24 hours in the medium and those collected directly from the follicle. However, the finding that dibutyryl cAMP induces a development of more pores along the nuclear membrane strongly suggests the possibility that this compound inhibits the maturation of oocytes by influencing the permeability of the nuclear membrane.

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Ansanella granifera gen. et sp. nov. (Dinophyceae), a new dinoflagellate from the coastal waters of Korea

  • Jeong, Hae Jin;Jang, Se Hyeon;Moestrup, Ojvind;Kang, Nam Seon;Lee, Sung Yeon;Potvin, Eric;Noh, Jae Hoon
    • ALGAE
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    • v.29 no.2
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    • pp.75-99
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    • 2014
  • A small dinoflagellate, Ansanella granifera gen. et sp. nov., was isolated from estuarine and marine waters, and examined by light microscopy, scanning electron microscopy, and transmission electron microscopy. In addition, the identity of the sequences (3,663-bp product) of the small subunit (SSU), internal transcribed spacer (ITS) region (ITS1, 5.8S, ITS2), and D1-D3 large subunit (LSU) rDNA were determined. This newly isolated, thin-walled dinoflagellate has a type E eyespot and a single elongated apical vesicle, and it is closely related to species belonging to the family Suessiaceae. A. granifera has 10-14 horizontal rows of amphiesmal vesicles, comparable to Biecheleria spp. and Biecheleriopsis adriatica, but greater in number than in other species of the family Suessiaceae. Unlike Biecheleria spp. and B. adriatica, A. granifera has grana-like thylakoids. Further, A. granifera lacks a nuclear fibrous connective, which is present in B. adriatica. B. adriatica and A. granifera also show a morphological difference in the shape of the margin of the cingulum. In A. granifera, the cingular margin formed a zigzag line, and in B. adriatica a straight line, especially on the dorsal side of the cell. The episome is conical with a round apex, whereas the hyposome is trapezoidal. Cells growing photosynthetically are $10.0-15.0{\mu}m$ long and $8.5-12.4{\mu}m$ wide. The cingulum is descending, the two ends displaced about its own width. Cells of A. granifera contain 5-8 peripheral chloroplasts, stalked pyrenoids, and a pusule system, but lack nuclear envelope chambers, a nuclear fibrous connective, lamellar body, rhizocysts, and a peduncle. The main accessory pigment is peridinin. The SSU, ITS regions, and D1-D3 LSU rDNA sequences differ by 1.2-7.4%, >8.8%, and >2.5%, respectively, from those of the other known genera in the order Suessiales. Moreover, the SSU rDNA sequence differed by 1-2% from that of the three most closely related species, Polarella glacialis, Pelagodinium bei, and Protodinium simplex. In addition, the ITS1-5.8S-ITS2 rDNA sequence differed by 16-19% from that of the three most closely related species, Gymnodinium corii, Pr. simplex, and Pel. bei, and the LSU rDNA sequence differed by 3-4% from that of the three most closely related species, Protodinium sp. CCMP419, B. adriatica, and Gymnodinium sp. CCMP425. A. granifera had a 51-base pair fragment in domain D2 of the large subunit of ribosomal DNA, which is absent in the genus Biecheleria. In the phylogenetic tree based on the SSU and LSU sequences, A. granifera is located in the large clade of the family Suessiaceae, but it forms an independent clade.

Acute Toxicity of Ozone on Survival and Physiological Conditions of Olive Flounder, Paralichthys Olivaceus (넙치(Paralichthys olivaceus)의 생존과 생리상태에 미치는 오존의 급성 독성)

  • Kim, Heung-Yun;Oh, Myung-Joo;Jung, Sung-Ju
    • Journal of fish pathology
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    • v.12 no.1
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    • pp.32-41
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    • 1999
  • Ozonization for rearing seawater in land-based culture system has recently been utilized for disinfection of pathogenic microorganisms and improvement of water quality. This study was conducted to examine the effects of total residual oxidants (TRO) in ozone-treated seawater on survival, blood parameters, osmolality and oxygen consumption, and gill tissue of the flounder. Paralichthys olivaceus. Experiments were carried out with the starved flounder of 12~19 cm in total length at $20^{\circ}C$. The 48-hr and 96-hr $LC_{50}$ for the flounder amounts to 26.4 ppb and 22.3 ppb, respectively. With increase of TRO concentration from 24 to 39 ppb, the values of hematocrit, hemoglobin concentration, red blood cell count and osmolality of the flounder with respect to exposure time were significantly elevated, however, the oxygen consumption rates decreased. In the case of the fish exposed to 13 ppb for 96 hrs, blood glucose increased with an elapse of exposure time, while survival rate was 100%. Death apparently resulted by massive destruction of gill lamellar epithelium, severe osmotic imbalance and the lack of oxygen uptake. The results of this experiment indicated that to protect aquaculture organisms, the ozone-treated seawater should not contain any residual oxidants, and that relatively long-term exposure to TRO of low concentration can impact on survival and physiological conditions of the flounder.

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The Effect of Jeju Wild Ginseng Extracts on Skin Barrier via Serine-Palmitoyltransferase (제주산양산삼이 세린-팔미토일 전이효소(Serine-Palmitoyltransferase)를 통해 피부 장벽에 미치는 효과에 대한 연구)

  • Kim, Hyo Min;Lee, Jung No;Kim, Jae Moon;Kim, Sung Kyu;Park, Sung-Min
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.2
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    • pp.119-126
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    • 2016
  • Skin is the largest organ that protects the body from the external environmental factors such as smog, cigarette smoke, UV. Protective skin barrier is composed with keratinizational keratinocytes and intercellular lipids such as ceramides, cholesterols and fatty acids combined by the lamellar liquid crystal structure. In this research, we confirmed that the Jeju wild ginseng (JWG) extracts dose-dependently increased the expression of serine-palmitoyltransferase (SPT) protein which is associated with ceramide biosynthesis. In addition, emulsion containing 5% JWG extract was applied on skin of human volunteers for 2 weeks and then significantly reduced transepidermal water loss (TEWL) compared to that of control group. As a results, JWG extract increased the biosynthesis of ceramides that is the key components of the skin lipid through enhancing expression of SPT. In addition, JWG extract reduced TEWL resulting in improvement of skin barrier function. In this context, we suggest that JWG extract could be used as a skin barrier enhancer and moisturing agents in cosmetic fileds.

A Comparison for Cervical Neural Foraminal Area by 3-dimensional CT in Normal Adults (3차원 컴퓨터단층촬영상을 이용한 정상 성인의 경추 신경공 면적 비교)

  • Kim, Yon-Min
    • Journal of radiological science and technology
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    • v.44 no.6
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    • pp.623-627
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    • 2021
  • Cervical foraminal stenosis is a disease in which the nerves that pass from the spinal canal to the limbs are narrowed and the nerves are compressed or damaged. Due to the lack of an imaging method that provides quantitatively stenosis, this study attempted to evaluate the area of the cervical vertebrae by reconstructing a three-dimensional computed tomography image, and to determine the area of the neural foramen in normal adults to calculate the stenosis rate. Using a three-dimensional image processing program, the surrounding bones including the posterior spinous process, lateral process, and lamellar bones of the cervical vertebra were removed so that the neural foramen could be observed well. A region of interest including the neural foraminal area of the three-dimensional image was set using ImageJ, and the number of pixels in the neural foraminal area was measured. The neural foraminal area was calculated by multiplying the number of measured pixels by the pixel size. To measure the largest neural foraminal area, it was measured between 40~50 degrees in the opposite direction and 15~20 degrees toward the head. The average area of the right C2-3 foramen was 44.32 mm2, C3-4 area was 34.69 mm2, C4-5 area was 36.41 mm2, C5-6 area was 35.22 mm2, C6-7 area was 36.03 mm2. The average area of the left C2-3 foramen was 42.71 mm2, C3-4 area was 32.23 mm2, C5-6 area was 34.56 mm2, and C6-7 area was 31.89 mm2. By creating a reference table based on the neural foramen area of normal adults, the stenosis rate of patients with neural foraminal stenosis could be quantitatively calculated. It is expected that this method can be used as basic data for the diagnosis of cervical vertebral foraminal stenosis.

Microscopic Characteristics of the Olfactory Organ in the Gluttonous Goby Chaenogobius gulosus(Pisces, Gobiidae), Compared to Sympatric Intertidal Gobies (별망둑 the gluttonous goby Chaenogobius gulosus 후각기관의 해부, 조직학적 특성 및 동소 망둑어과 출현종들과의 비교연구)

  • Kim, Hyun Tae;Park, Jong Young
    • Korean Journal of Ichthyology
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    • v.33 no.1
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    • pp.1-7
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    • 2021
  • Using stereo, light, and scanning electron microscopes, we researched the anatomical and histological structure of Chaenogobius gulosus's olfactory organ and compared it to those of sympatric gobies Luciogobius guttatus and Favonigobius gymnauchen. Results revealed the following common characteristics: i) tubular anterior nostril (AN) and flat posterior nostril (PN), ii) a single longitudinal lamella, iii) two accessory nasal sacs (ANS, ethmoidal and lacrimal), iv) abundant sensory epithelium lymphatic cells (LC), v) an eosinophil cell, and vi) a ciliary length a quarter of the knob diameter in the olfactory receptor neuron (ORN). Some characteristics are specific to C. gulosus and different from the other two gobies: i) 0.5~1.0 mm AN and 0.2~0.5 mm PN (vs. 0.2~0.3 mm and 0.2~0.3 mm in L. guttatus; 0.2~0.4 mm and 0.1~0.3 mm in F. gymnauchen), ii) two ANS (vs. absence in L. guttatus; two in F. gymnauchen), iii) abundant LC (vs. low in L. guttatus and F. gymnauchen), iv) low density non-sensory cilia on the lamellar surface (vs. high in L. guttatus; low in F. gymnauchen), and v) a quarter ciliary length to knob diameter ratio in the ORN (vs. mixture of a quarter to equal ratio in L. guttatus; two or three times in F. gymnauchen). From these results, we confirmed the C. gulosus olfactory organ has adapted anatomically and histologically to the sand-rock tidal zone.