• Title/Summary/Keyword: cone cell

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The Ultrastructure of Photoreceptor Cells in Frog Retina (개구리 망막에 있는 광수용세포의 미세구조)

  • Kim, Jin-Suk;Jeon, Jin-Seok
    • Applied Microscopy
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    • v.25 no.4
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    • pp.115-123
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    • 1995
  • This study was carried out to observe the functional ultrastructures of photoreceptor cells in frog(Rana catesbeiana) retina using transmission electron microscope. The photoreceptor cells are divided into two types-rod and cone cells-consist of outer and inner segment. The long outer segment of rod cell contains dense stacks of membrane and formed vertical and horizontal folds. The outer segment of cone cell is small, and vertical and horizontal folds are not exist. The electron dense cytoplasm of rod cell contains compact mitochondria, Golgi complexes, and endoplasmic reticula. The inner segment of cone cell shows low electron density and contains a large lipid droplet in the upper part of inner segment. In addition, cone cell contains many mitochondria, Golgi complexes. rough endoplasmic reticula, ribosomes and numerous glycogen particles. It is believed that these ultrastructural characteristics are closely associated with photoreceptive function of photoreceptor cells in frog retina.

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Immunomodulatory Effects of an Extract from Pinus koraiensis Cone Peel in LP-BM5 Murine Leukemia Viruses-Induced Murine Acquired Immune Deficiency Syndrome (면역 결핍 동물모델에서 잣피 추출물의 면역조절 효과)

  • Kim, Seong Pil;Kwon, Han Ol;Ha, Yejin;Heo, Seok Hyun;Lee, Jeongmin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.9
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    • pp.1027-1034
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    • 2017
  • The immune system is a complex process within the body that protects against disease. Recently, many studies have attempted to discover immunomodulative compounds from natural sources. Pinus koraiensis (PK) cone shell is a by-product of PK. One of the major compounds of PK cone shell is dehydroabietic acid, which has bioactivity, including antiulcer and anti-inflammatory activities. Therefore, this study was performed to examine the immunomodulative effects of PK cone shell. The immunomodulatory effects of PK cone shell extracted with 20% ethanol (EtOH) in vivo were examined initially by measuring the natural killer (NK) cell activity, phagocytic activity, Th1/Th2 cytokines release, serum immunoglobulin, and T/B cell proliferation. The NK cell activity and phagocytic activity were increased significantly by a treatment with a 20% EtOH extract of PK cone shell. Th1 type cytokine and T cell proliferation increased and Th2 type cytokine, B cell proliferation and serum immunoglobulin A, G, and E decreased after a treatment with PK cone shell extract. The 20% EtOH extract of the PK cone shell normalized the unbalanced production of Th1/Th2 type cytokine. This suggests that a 20% EtOH extract of PK cone shell has great potential as a health food.

The Analysis of Color Vision Defects Mechanism for the Electric Circuits (전기적 회로에 의한 색각이상 mechanism 해석)

  • Park, Sang-An;Kim, Yong-Geun
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.1
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    • pp.81-85
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    • 2001
  • The color vision was composed of the wavelength absorption of three R. G. B cone photo-receptors and the r-g, y-b channel of an opponent process. The color vision defects mechanism for the electric circuit made up a photo cell, relay switch and transformer. This mechanism very well applied to the color vision defects mechanism owing to be y-b chromatic valence function in case of a cone R or G defects and to be r-g chromatic valence function in case of a cone B defects.

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A Histological Study on the Visual Cell Layer of the Endemic Korean Species Liobagrus mediadiposalis (Pisces: Amblycipitidae)

  • Kim, Jae Goo;Park, Jong Young
    • Applied Microscopy
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    • v.47 no.4
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    • pp.238-241
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    • 2017
  • A study on the visual cell and eyeball of the endemic Korean species Liobagrus mediadiposalis was investigated by light and electron microscopes. The retina of a small and 2 mm-diameter round eye was thin, $151.0{\pm}4.0{\mu}m$ and has two visual cells, a single cone and a rod cell. The single cone cells are short and thick, $18.0{\pm}0.9{\mu}m$ in length and $5.1{\pm}0.7{\mu}m$ (n=30) in diameter, while the rod cells are longer and thinner, $54.8{\pm}2.9{\mu}m$ in length and $3.3{\pm}0.6{\mu}m$ in diameter. The cone cells are seen an irregular and random mosaic pattern, and the rod cells are also randomly situated at between cone cells. As a rare phenomenon, such structure is one of characteristics reflecting the eye of a nocturnal and bottom-dwelling freshwater fish. The ultrastructure of visual cells was observed with scanning and transmission electron microscopy, both cone and rod cells are divided into an inner segment with numerous mitochondria and an outer segment with stacks of membrane discs.

The $GABA_c$ Receptor Is Present in Isolated Cone-Horizontal Cell Axon Terminals From Catfish Retina

  • Jung, Chang-Sub;Lee, Sung-Jong;Paik, Sun-Sook;Bai, Sun-Ho
    • Proceedings of the Korean Biophysical Society Conference
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    • 1998.06a
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    • pp.35-35
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    • 1998
  • Catfish retina contains cone- and rod-horizontal cells. Only the cone-horizontal cell (cone-HC) has an axon and axon terminal. We compared the distribution of excitatory and inhibitory receptors in axon terminals and somata to begin to learn about the distinct functions of these two structures.(omitted)

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Comparative Study of the Retinal Structure in Two Korean Endemic Freshwater Fishes, Zacco koreanus (Cyprinidae) and Pseudobagrus koreanus (Bagridae) Based on Their Habitats (참갈겨니 Zacco koreanus와 눈동자개 Pseudobagrus koreanus의 생태학적 차이에 의한 망막 조직의 비교 연구)

  • You, Min-Jeong;Park, Jong-Young
    • Korean Journal of Ichthyology
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    • v.20 no.2
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    • pp.97-104
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    • 2008
  • Comparative study of retinal structure in two Korean endemic freshwater fishes, Zacco koreanus and Pseudobagrus koreanus, was carried out by light and scanning electron microscopy. In the visual cell layer comprised of cone cells and rod cells, the cone cells showed a distinct difference between both species. Z. koreanus had two types of cone cells, single cone cells including a long single and short single cone cells, and double cone cells, whereas P. koreanus had only one type of single cone cells having no its short single and long single cones. Meanwhile, the cone cells of Z. koreanus were arranged in more compact-rowed pattern, but it was more loose and irregular in P. koreanus. Based on field observation, Z. koreanus is mainly a epipelagic or sometimes benthopelagic and a diurnal fish with a round and large eye, while P. koreanus is a demersal and nocturnal fish with an oval and small eye. Therefore, the difference in the retinal structure of two species seems to be closely related to their ecological habitats.

Applicability of Mini-Cone Penetration Test Used in a Soil Box

  • Sugeun Jeong;Minseo Moon;Daehyeon Kim
    • Journal of the Korean Geosynthetics Society
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    • v.22 no.4
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    • pp.83-92
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    • 2023
  • In this study, we conducted verification of key influencing factors during cone penetration testing using the developed Mini Cone Penetration Tester (Mini-CPT), and compared the experimental results with empirical formulas to validate the equipment. The Mini-CPT was designed to measure cone penetration resistance through a Strain Gauge, and the resistance values were calibrated using a Load Cell. Moreover, the influencing factors were verified using a model ground constituted in a soil box. The primary influencing factors examined were the boundary effect of the soil box, the distance between cone penetration points, and the cone penetration speed. For the verification of these factors, the experiment was conducted with the model ground having a relative density of 63.76% in the soil box. It was observed that the sidewall effect was considerably significant, and the cone penetration resistance measured at subsequent penetration points was higher due to the influence between penetration points. However, within the speed range considered, the effect of penetration speed was almost negligible. The measured cone penetration resistance was compared with predicted values obtained from literature research, and the results were found to be similar. It is anticipated that using the developed Mini-CPT for constructing model grounds in the laboratory will lead to more accurate geotechnical property data.

Anatomical variations of the ethmoid sinuses and their association with health or pathology of the ethmoid and maxillary sinuses in a Southern Chinese population: An analysis using cone-beam computed tomography

  • Hui, Liuling;Hung, Kuo Feng;Yeung, Andy Wai Kan;Arx, Thomas von;Leung, Yiu Yan;Bornstein, Michael M.
    • Imaging Science in Dentistry
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    • v.52 no.1
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    • pp.109-115
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    • 2022
  • Purpose: The aim of this study was to evaluate the prevalence of clinically relevant anatomical variations of the ethmoid sinuses and their potential association with ethmoid and maxillary sinus pathologies on cone-beam computed tomography (CBCT) scans. Additionally, potential associations with different sides and demographic factors, including age and sex, were evaluated. Materials and Methods: In total, 273 CBCT scans with complete ethmoid and maxillary sinuses were analyzed to determine the prevalence of Agger nasi cell, supraorbital ethmoid cell, Haller cell, Onodi cell, and ethmomaxillary sinus. In addition, the health or pathology of the ethmoid and maxillary sinuses was also recorded to assess correlations with the aforementioned variations. Results: The prevalence of Agger nasi cell was found to be the highest (95.6%) in this study, followed by Onodi cell (60.4%), Haller cell (29.3%), and supraorbital ethmoid cell (19.4%). Ethmomaxillary sinus was the least common finding (16.5%). Males and persons above 61 years of age had a significantly higher frequency of supraorbital ethmoid cell and Onodi cell, respectively. However, no significant relationships were noted between anatomical variations of the ethmoid sinus and pathologies of the ethmoid or maxillary sinus. Conclusion: There was a high prevalence of ethmoid sinus variations in this Southern Chinese population. The prevalence of Agger nasi cell and Onodi cell was higher than that of other anatomical variations of the ethmoid sinuses. Anatomical variations of the ethmoid sinuses were not associated with ethmoid or maxillary sinus pathologies in this patient cohort.

Correlations between anatomical variations of the nasal cavity and ethmoidal sinuses on cone-beam computed tomography scans

  • Shokri, Abbas;Faradmal, Mohammad Javad;Hekmat, Bahareh
    • Imaging Science in Dentistry
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    • v.49 no.2
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    • pp.103-113
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    • 2019
  • Purpose: Anatomical variations of the external nasal wall are highly important, since they play a role in obstruction or drainage of the ostiomeatal complex and ventilation and can consequently elevate the risk of pathological sinus conditions. This study aimed to assess anatomical variations of the nasal cavity and ethmoidal sinuses and their correlations on cone-beam computed tomography (CBCT) scans. Materials and Methods: This cross-sectional study evaluated CBCT scans of 250 patients, including 107 males and 143 females, to determine the prevalence of anatomical variations of the nasal cavity and ethmoidal sinuses. All images were taken using a New Tom 3G scanner. Data were analyzed using the chi-square test, Kruskal-Wallis test, and the Mann-Whitney test. Results: The most common anatomical variations were found to be nasal septal deviation (90.4%), agger nasi air cell (53.6%), superior orbital cell(47.6%), pneumatized nasal septum(40%), and Onodi air cell(37.2%). Correlations were found between nasal septal deviation and the presence of a pneumatized nasal septum, nasal spur, and Haller cell. No significant associations were noted between the age or sex of patients and the presence of anatomical variations (P>0.05). Conclusion: Radiologists and surgeons must pay close attention to the anatomical variations of the sinonasal region in the preoperative assessment to prevent perioperative complications.

Comparative Morphological Aspects for the Opening Phenomenon in the Cone of Pinus densiflora (소나무 구과의 열개 현상에 대한 비교형태학적 연구)

  • 임동옥;김철환
    • Korean Journal of Environmental Biology
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    • v.20 no.4
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    • pp.386-390
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    • 2002
  • The opening phenomenon of mature female cone in Pinus densiflora aye observed from the anatomical characteristics. The differentiation of tissue in young cone aye not complete and are going on. In the green cone as large as the adult cone, shrink-age rate of vascular strands and sclerenchyma aye 1.0∼1.5% and 14.0∼16.0% respectively. The end parts of cone scales are composed of the parenchymatous cell and sclerenchyma. The middle parts in cone scales are composed of the sclerenchyma and vascular strands with the same thickness and more thin than the thickness of the end part and basal one. But thickness of sclerenchyma which compose of scale prop in the basal part of cone scale aye twice than that of vascular strand. In mature cone, the opening phenomenon of the pine cone results from the difference of shrinkage rate between vascular bundle and sclerenchyma. Especially, opening of cone scales are due to larger shrinkage rate of sclerenchyma than vascular strands in the basal part of cone scale.