• Title/Summary/Keyword: Segment cell

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Development of Fuel Rod Fretting Wear Tester (핵연료봉 프레팅마멸 시험기 개발)

  • 김형규;하재욱;윤경호;강흥석;송기남
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.11a
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    • pp.245-251
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    • 2001
  • A fretting wear tester is developed for experimental study on the fuel fretting problem of light water reactor. The feature of the developed tester is it can simulate the existence of gap between spring and fuel rod as well as different contacting force including the just-contact condition (0 N on the contact). Used are a servo-motor, an eccentric cylinder and lever mechanism for driving system. A spacer grid cell is constituted with four strap segments (each segment has a spring). This fretting wear tester can also be used as a fatigue tester of a spacer grid spring with the frequency of more than 10 Hz. It is required to simulate the frequency of the vibrating fuel rod due to flow-induced vibration in a reactor. In fretting wear test, up to two span-length of a fuel cladding tube can be accommodated. A specimen of cladding tube of one span-length is specially designed, which can be extended for two-span test. For .fatigue test, a device for clamping the spring fixture is installed additionally, Presently, the tester is designed for the condition of air environment and room temperature. The variation of the reciprocal distance is measured to check the stability of input force, which will be exerted to the cladding (for fretting wear. test) and the spring (for fatigue test) specimen.

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Effects of Cyclophosphamide in the Epididymis of the Rat II. Corpus (Cyclophosphamide가 흰쥐의 부정소에 미치는 영향 II. 체 부)

  • Cho, Kwang-Phil;Kim, Jeong-Sang;Jung, Hae-Man
    • Applied Microscopy
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    • v.22 no.2
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    • pp.127-140
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    • 1992
  • This research was undertaken to determine the effects of the cyclophosphamide (CP) on the epididymal corpus of the male rat in terms of ultrastructural alteration and protein analysis by SDS-PAGE at different groups; control group, 1 week group, 3 weeks group and 5 weeks group were treated with saline (control group) or CP at doses of 20mg/kg/week, 1 time a week, respectively. In the cytoplasm of the principal cells on the epididymal corpus, the mitochondria were significantly swollen or disrupted. The lumens of rough endoplasmic reticulum (rER) were also dilated and the number of secretory vesicles and lysosomes were increased respectively. CP caused changes in protein concentrations in the corpus of epididymis after CP treatment. Total proteins of 31 to 36 species were expressed in the corpus fluid. Then the more CP was increased, the more concentration of proteins caused to decrease, synthesize or increase in epididymal corpus. In contrast to the control group, in particular 88KD and the other 8 proteins in the corpus fluid, were decreased or disappeared respectively, whereas acid phosphatase and the other 9 proteins in the corpus fluid, were increased or synthesized respectively. The other proteins are not showed distinctive difference. It is suggested that treatment with CP alters the specific cell organelles and proteins in segment of the epididymal corpus.

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Transdermal scopolamine for the treatment of recurrent parotid sialocele: a case report

  • Chi Hyun Lee;Changryul Claud Yi;Yong Chan Bae;Jae Woo Lee;Byung-Joo Lee;Joo Hyoung Kim
    • Archives of Craniofacial Surgery
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    • v.25 no.1
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    • pp.44-47
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    • 2024
  • Recurrent parotid sialocele is rare and challenging to treat. Treatment options are limited for cases of parotid sialocele that recur despite ductal ligation. This case study presents a patient who underwent wide excision of the right buccal mucosa due to squamous cell carcinoma. During the wide excision, a segment of the parotid duct was excised, and ductal ligation was performed to prevent the occurrence of a sialocele, followed by reconstruction using a folded anterolateral thigh free flap. Twenty-two days after surgery, parotid sialocele occurred despite the initial ductal ligation and subsequent ductal ligation was performed; however, the sialocele recurred. As an alternative therapeutic option, a transdermal scopolamine patch was applied for 3 weeks, with one patch used every 3 days. The results were encouraging, with complete resolution of the sialocele. A transdermal scopolamine offers a noninvasive, convenient method of treating parotid sialocele with minimal side effects. The successful outcome of this case suggests that a transdermal scopolamine can be an effective therapeutic option for recurrent parotid sialocele in conjunction with surgical treatment.

A marginal branch of the left hepatic artery running along the umbilical vein and supplying the anterior surface of the liver left lobe: a report of 5 cases in 12 Japanese human fetuses

  • Ji Hyun Kim;Shogo Hayashi;Gen Murakami;Jose Francisco Rodriguez-Vazquez;Hiroshi Abe
    • Anatomy and Cell Biology
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    • v.56 no.4
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    • pp.579-583
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    • 2023
  • In human fetuses, the left hepatic artery (LHA) issues the marginal artery that runs along the umbilical vein and, sometimes, reaches the umbilicus. The further observation demonstrated that, in 5 of 12 Japanese midterm fetuses (crown-rump length mm: 46, 50, 54, 59, 102), the marginal artery issued not only a thin umbilical branch but also a liver parenchymal branch that took a posterosuperior recurrent course in a peritoneal fold and supplied the anterior surface of the liver left lobe (segment III). However, in 22 Spanish fetuses of which gestational ages corresponded to the Japanese ones, we did not find the parenchymal branch. Therefore, between human populations, there seemed to be a considerable difference in the incidence as to whether or not the marginal artery issues the liver parenchymal branch. The parenchymal branch might be degenerated at the later stages due to friction between the liver free surface and growing diaphragm.

An anatomical investigation of the suboccipital- and inferior suboccipital triangles

  • Kirsten Shannon Regan;Gerda Venter
    • Anatomy and Cell Biology
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    • v.56 no.3
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    • pp.350-359
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    • 2023
  • The suboccipital triangle (ST) is a clinically relevant landmark in the posterior aspect of the neck and is used to locate and mobilize the horizontal segment of the third part of the vertebral artery before it enters the cranium. Unfortunately, this space is not always a viable option for vertebral artery exposition, and consequently a novel triangle, the inferior suboccipital triangle (IST) has been defined. This alternative triangle will allow surgeons to locate the artery more proximally, where its course is more predictable. The purpose of this study was to better define the anatomy of both triangles by measuring their borders and calculating their areas. Ethical clearance was obtained from the University of Pretoria (reference number: 222/2021) and both triangles were subsequently dissected out on both the left and right sides of 33 formalin-fixed human adult cadavers. The borders of each triangle were measured using a digital calliper and the areas were calculated using Herons Formula. The average area of the ST is 969.82±153.15 mm2, while the average area of the IST is 307.48±41.31 mm2. No statistically significant differences in the findings were observed between the sides of the body, ancestry, or sex of the cadavers. Measurement and analysis of these triangles provided important anatomical information and speak to their clinical relevance as surgical landmarks with which to locate the vertebral artery. Of particular importance here is the IST, which allows for mobilisation of this artery more proximally, should the ST be occluded.

An unusual arrangement between the highest denticulate ligament and posterior inferior cerebellar artery

  • Aditi Patel;Johnathan Baudoin;Arada Chaiyamoon;Juan J. Cardona;Ana Carrera;Francisco Reina;Joe Iwanaga;Aaron S. Dumont;R. Shane Tubbs
    • Anatomy and Cell Biology
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    • v.56 no.3
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    • pp.394-397
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    • 2023
  • The posterior inferior cerebellar artery (PICA) is often involved in pathologies of the posterior cranial fossa. Therefore, a good understanding of the vessel's normal and variant courses is important to the neurosurgeon or neurointerventionalist. During the routine microdissection of the craniocervical junction, an unusual arrangement between the highest denticulate ligament and PICA was observed. On the right side, the PICA was given rise to by the V4 segment of the vertebral artery 9 mm after the artery entered the dura mater of the posterior cranial fossa. The artery made an acute turn around the lateral edge of the highest denticulate ligament to then recur 180 degrees and travel medially toward the brainstem. Invasive procedures that target the PICA should be aware of the variant as described herein.

Plant Regeneration from Cell Suspension Culture Using Leaf Callus in Actinidia deliciosa X A. arguta Clone 118 (양다래X다래 클론 118의 엽조직 캘러스를 이용한 세포 현탁배양으로부터 식물체 유도)

  • Kim Yong-Wook;Moon Heung-Kyu
    • Journal of Plant Biotechnology
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    • v.32 no.4
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    • pp.287-292
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    • 2005
  • Calli were induced by culturing the leaf segment of Actinidia deliciosa ${\times}$ A. arguta clone 118 on MS medium supplemented with 0.5 mg/L 2,4-D, 0.1 mg/L NAA and 0.05 mg/L BA for 8 weeks in light condition. The induced calli were inoculated in liquid MS medium containing 0.5 mg/L 2,4-D, 0.1 mg/L NAA, 0.05 mg/L BA and 3% sucrose to establish cell suspension culture. The cells at the exponential stage and the stationary stage could be observed between 5-11 days and after that 12 days in culture, respectively. The fresh weight of callus induced from the suspended cells did not vary much among the media containing eight different combinations of plant growth regulators tested. The highest frequency of shoot induction (88.3%) was observed in MS medium containing 2.0 mg/L zeatin. Either BA or zeatin mixed with thidiazuron (TDZ) seemed to be effective in shoot induction. The induced shoots were transferred to MS medium containing 0.2 mg/L zeatin for further shoot growth. And then the shoots were transferred to Standardi (ST) medium containing 1.0 mg/L indolebutyric acid (IBA) for rooting. Plantlets could be obtained through cell suspension culture of Actinidia deliciosa ${\times}$ A. arguta clone 118.

Upregulation of aquaporin 2 and aquaporin 4 in the water-deprived mongolian gerbil (Meriones unguiculatus) kidney (절수시 Mongolian gerbil (Meriones unguiculatus) 콩팥의 Aquaporin 2, Aquaporin 4 발현변화)

  • Song, Ji-Hyun;Kwon, Jin-Seuk;Kim, Yong-Hwan;Park, Yong-Deok;Han, Ki-Hwan;Ryu, Si-Yun;Jung, Ju-Young
    • Korean Journal of Veterinary Research
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    • v.47 no.4
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    • pp.363-370
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    • 2007
  • Mongolian gerbil (Meriones unguiculatus) has been as an model animal for studing the neurological disease such as stroke and epilepsy because of the congenital incompleteries in Willis circle, as well as the investigation of water metabolism because of the long time-survival in the condition of water-deprived desert condition, compared with other species animal. Aquaporin 2 (AQP2) expressed at the surface of principal cells in collecting duct results from an equilibrium between the AQP2 in intracellular vesicles and the AQP2 on the plasma membrane. Aquaporin 4 (AQP4), which is expressed in cell in a wide range of organ, is also present in the collecting duct principal cells where this is abundant in the basolateral plasma membranes and represent potential exit pathways from the cell for water entering via AQP2. In this research, we divide 3 groups of which each group include the 5 animals. In the study of 7 or 14 days water restricted condition, we investigated the AQP2 and AQP4 by using a quantitative immunohistochemistry in the kidney. The results obtained in this study were summarized as followings. AQP2 is abundant in the apical plasma membrane and apical vesicles in the collecting duct principal cell and at rare abundance in connecting tubules. In the water-deprived Mongolian gerbil kidney, expression of AQP2 was continuosly increased in the cortical collecting duct and inner medullary collecting duct. This increase was both the apical region and cytoplasm. AQP4 is mainly expressed in the inner medulla, although some expression is also noted in the more proximal segment. In the water-deprived Mongolian gerbil kidney, AQP4 was also increased in the inner medullary collecting duct. Immunoactivity was increased in entire inner medullary collecting duct and newly detected in cytoplasm of principal cell. These findings suggest that increased levels of AQP2 and AQP4 in the cortical and inner medulalry collecting duct may play a important role for maintain fluid balance in the water-deprived kidney.

Histological Changes in Reproductive Organs of Pubescent Male Mice in Response to ICI 182, 780 Treatment and Recovery of the Organs with Time (ICI 182, 780을 투여한 사춘기 수컷 생쥐 생식기관의 조직학적 변화와 시간에 따른 회복)

  • Mo, Yun Jeong;Choi, Hayana;Cho, Young Kuk;Park, Mi Suk;Cho, Hyun Wook
    • Journal of Life Science
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    • v.25 no.12
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    • pp.1415-1424
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    • 2015
  • ICI 182, 780 (ICI) has been used as an estrogen receptor inhibitor in several mammalian species. This study was conducted to observe histological changes in the reproductive system of pubescent male mice following ICI treatment, as well as to investigate the recovery of the organs over time. To accomplish this, ICI at 5 mg/0.1 ml of castor oil was subcutaneously injected into 5-week-old male mice once per week for 4 weeks. The mice were then randomly divided into no-recovery, 150-day recovery, and 300-day recovery groups. The testis of the no-recovery group showed atrophy of the seminiferous tubules, with decreased Sertoli cell numbers and thickness of the germinal epithelium. In the epididymis, the cell height of epithelial tissues was altered, but these changes were not observed in the 300-day recovery group. In the efferent ductule, the luminal diameter was increased, but the cell height of the epithelial tissues was decreased. In the prostate and seminal vesicles, the cell height of the epithelial tissues was increased, and these changes were not observed in the 150-day recovery group. These results show that ICI causes histological changes in pubescent male reproductive organs but that these changes are resolved with time.

Multicotyledonary Structure of Somatic Embryos Formed from Cell Cultures of Daucus carota L. (당근의 배양세포로부터 형성된 체세포배의 다자엽 구조)

  • 소웅영
    • Journal of Plant Biology
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    • v.39 no.1
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    • pp.71-77
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    • 1996
  • Embryogenic callus was selected from callus induced from hypocotyl segment cultures of Daucus carota seedlings on MS basal medium supplemented with 1.0 mg/L 2,4-D. Cell clumps prepared from the embryogenic callus were transferred to MS medium without 2,4-D for somatic embryo development. Cotyledonary abnormalities were frequently observed on somatic embryos developed after the incubation of cell clumps in MS basal medium with 1.0 mg/L 2,4-D for one week and then subculture in the same medium but without 2.4-D for two weeks. The percentage of abnormalities was as follows: 5% one cotyledon, 21% three cotyledons, 6% four cotyledons, 5% five cotyledons, 0.2% six cotyledons and 1% trumpet-like cotyledons. On the other hand, the normal somatic embryo with two cotyledons appeared at 63%. The germination rate of somatic embryos was higher in two cotyledon somatic embryos than in multicotyledonary embryos. Trumpet-like somatic embryos did not germinate normally showing limited elongation and enlargement of roots and cotyledons without shoot development. From anatomical examination circular procambium in the root of somatic embryo began to branch around the middle regions of the hypocotyl which extended into the cotyledons through the cotyledonary nodes and the number of branched procambial strands in hypocotyl was equal to the number of cotyledons. Monocotyledonous somatic embryo always had larger cotyledon than that of somatic embryos with multicotyledons and had horseshoe-like cotyledons where the procambium was of the same structure.ucture.

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