백서에 있어서 incision 중지가 하악두 연골의 성장 및 미세구조에 미치는 영향

성재현,배용철,박매자,주강,경희문 대한치과교정학회 1994 대한치과교정학회지 Vol.24 No.3

The purpose of this study is to investigate the effect of loss of incisal function on the thickness, growth activities, ultrastructure of the condylar cartilage and on the muscle fibers of masseter superficialis, anterior belly of digastric muscle in the growing rats. 37 day-old-rats of which incisors had been trimmed every day received soft diet from weaning and were studied by the autoradiography, electron microscopy and muscle histochemistry. The results obtained were as follows ; The thickness of the fibrous, proliferative layer in superior, posterosuperior portion of the condylar cartilage was significantly(p<0.01) reduced in experimental groups and the decrease rate of fibrous layer thickness was greater in posterosuperior portion than in superior portion of cartilge and was greater than in proliferative layer. In normal group, more cells of posterosuperior portion moved more rapidly towards the medullary cavity. In experimental group, the labelling index of posterosuperior portion was decreased in proliferative layer at 2 hours, in transitional layer at 1, 2 days, in hypertrophic layer at 4 days after injection relative to posterosuperior portion of control group. But labelling index of superior portion was not different form that of control group at all time course after injection. From the muscle histochemistry, the diameter of type IIB fibers in masseter superficialis muscle, type ⅡA, type IIB fibers in anterior belly of digastric muscle decreased significantly(p<0.01) relative to controls in experimental group. From electron microscopic study, in the fibrous layer of the posterosuperior portion of condylar cartilage in normal group, many fibroblast like cells near the joint cavity showed extensive remodelling activities in ultrastructure. There was no morphological changes between experimental and control group in all cartilage cell layers of superior portion but cells near the joint cavity in fibrous layer of posterosuperior portion of experimental group showed morphologically inactive state relative to control group.

Ultrastructure of Spermatozoa in Pungtungia herzi

이영환,김구환 한국발생생물학회 1998 발생과 생식 Vol.2 No.2

돌고기 Pungtungia herzi 정자의 미세구조를 주사 및 투과 전자현미경적 방법으로 연구하였다. 정자는 구형의 두부, 짧은 중편 및 꼬리로 구성되어 있으며 비교적 그 구조가 단순하고 그 길이는 약 37.4이었다. 정자의 미세구조에서 핵에 대한 접선 방향으로의 편모 배열, 짧은 핵 그리고 미토콘드리아의 비대칭적 배열은 잉어과 정자의 공통된 특징과 마찬가지로 나타났으며, 대부분의 경골어류에서와 같이 첨체를 가지고 있지 않았다. 반면 돌고기 정자에서는 The fine structure of spermatozoa of Pungtungia herzi was examined with scanning and transmission electron microscopies. The spermatozoa of p. herzi are approximately 37.4 in length and a relatively simple cell with a spherical nucleus, a short midpiece and a tail. The acrosome is not present as in most teleost fishes. The ultrastructure of spermatozoa represents typical characteristics of cyprinid spermatozoa including the lateral insertion of flagellum, the organization of centriolar complex in shallow nuclear fossa, and the occurrence and asymmetrical arrangement of mitochondria. In the nuclear envelope and mitochondrion, however there were some morphological differences for their ultrastructure. The nuclear envelope is severely undulated and the shallow nuclear fossa contains two centrioles which are at the angle of some 130 each other. The most significant feature can be observed with the mitochondrion; five or more mitochondria, which are shown in primary spermatocyte, fuse to form a single one in the mature spermatozoon. The mitochondrial aspect is different from that of other cyprinid spermatozoa, where their mitochondria have a conventional aspect and never fuse to form a mitochondrial derivative. In terms of sperm evolution the fused mitochondria are regarded as the apomorphic character in comparison with the separate mitochondria. The single mitochondrion is not reported in cyprinid spermatozoon except the case of Rhodeus.

Newly recorded species of the genus Synura (Synurophyceae) from Korea

조복연,김한순 한국생태학회 2017 Journal of Ecology and Environment Vol.41 No.1

Background: Species in the heterokont genus Synura are colonial and have silica scales whose ultrastructural characteristics are used for classification. We examined the ultrastructure of silica scales and molecular data (nuclear SSU rDNA and LSU rDNA, and plastid rbcL sequences) to better understand the taxonomy and phylogeny within the section Petersenianae of genus Synura. In addition, we report the first finding of newly recorded Synura species from Korea. Results: We identified all species by examination of scale ultrastructure using scanning and transmission electron microscopy (SEM and TEM). Three newly recorded species from Korea, Synura americana, Synura conopea, and Synura truttae were described based on morphological characters, such as cell size, scale shape, scale size, keel shape, number of struts, distance between struts, degree of interconnections between struts, size of base plate pores, keel pores, base plate hole, and posterior rim. The scales of the newly recorded species, which belong to the section Petersenianae, have a well-developed keel and a characteristic number of struts on the base plate. We performed molecular phylogenetic analyses based on sequence data from three genes in 32 strains (including three outgroup species). The results provided strong statistical support that the section Petersenianae was monophyletic, and that all taxa within this section had well-developed keels and a defined number of struts on the base plate. Conclusions: The phylogenetic tree based on sequence data of three genes was congruent with the data on scale ultrastructure. The resulting phylogenetic tree strongly supported the existence of the section Petersenianae. In addition, we propose newly recorded Synura species from Korea based on phylogenetic analyses and morphological characters: S. americana, S. conopea, and S. truttae.

Effect of Freezing and Thawing on the Histology and Ultrastructure of Buffalo Muscle

Sen, A.R.,Sharma, N. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.9

Histology and transmission electron microscopy studies were carried out on buffalo muscles that were subjected to repeated freeze-thaw cycles at -10 and $-18^{\circ}C$. In the first freeze thaw cycle ($-10^{\circ}C$) structures of muscle showed slight change and closely resembled to those of normal muscle. There were frequent gaps in the half way across the fibres and some cracks in individual fibre were also noticed in second freeze thaw cycle. In the muscle frozen at $-18^{\circ}C$, more pronounced shrinkage with extensive damage of fibres with tearing was observed. The interfibrillar gaps were wider, shrinkage and tearing of the fibres were more distinct after second freeze-thaw cycle. After the second cycle, the interior portion showed large scale degradation of the ultrastructure. Our studies of buffalo muscle showed that under the proper condition, little structural damage takes place in the meat histology and ultrastructure under repeated freeze-thaw conditions. This study adds continued weight to the evidence that limited freeze-thaw cycles will not deteriorate the quality of meat.

Newly recorded species of the genus Synura (Synurophyceae) from Korea

Jo, Bok Yeon,Kim, Han Soon The Ecological Society of Korea 2017 Journal of Ecology and Environment Vol.41 No.1

Background: Species in the heterokont genus Synura are colonial and have silica scales whose ultrastructural characteristics are used for classification. We examined the ultrastructure of silica scales and molecular data (nuclear SSU rDNA and LSU rDNA, and plastid rbcL sequences) to better understand the taxonomy and phylogeny within the section Petersenianae of genus Synura. In addition, we report the first finding of newly recorded Synura species from Korea. Results: We identified all species by examination of scale ultrastructure using scanning and transmission electron microscopy (SEM and TEM). Three newly recorded species from Korea, Synura americana, Synura conopea, and Synura truttae were described based on morphological characters, such as cell size, scale shape, scale size, keel shape, number of struts, distance between struts, degree of interconnections between struts, size of base plate pores, keel pores, base plate hole, and posterior rim. The scales of the newly recorded species, which belong to the section Petersenianae, have a well-developed keel and a characteristic number of struts on the base plate. We performed molecular phylogenetic analyses based on sequence data from three genes in 32 strains (including three outgroup species). The results provided strong statistical support that the section Petersenianae was monophyletic, and that all taxa within this section had well-developed keels and a defined number of struts on the base plate. Conclusions: The phylogenetic tree based on sequence data of three genes was congruent with the data on scale ultrastructure. The resulting phylogenetic tree strongly supported the existence of the section Petersenianae. In addition, we propose newly recorded Synura species from Korea based on phylogenetic analyses and morphological characters: S. americana, S. conopea, and S. truttae.

Ultrastructural Changes During Programmed Cell Death of Tobacco Leaf Tissues Infected with Tobacco mosaic virus

Shin, Jun-Seong,Kim, Young-Ho,Chae, Soon-Yong The Korean Society of Plant Pathology 2001 Plant Pathology Journal Vol.17 No.6

Tobacco (Nicotiana tabacum cvs.Xanthi-nc and NC 82) plants infected with Tobacco mosaic virus (TMV) were examined ultrastructurally. Local lesions produced by TMV were sunken and withered. The plants were subjected to temperature shift (TS), a method to produce programmed cell death (PCD), by placing the infected plants initially at high temperature (35$^{\circ}C$) for 2 days and then shifting them to greenhouse temperature (22-27$^{\circ}C$). As a result, expanded lesions around the original necrotic lesions were produced. The expanded area initially had no symptoms, but it withered and became necrotic 15 h after TS. No ultrastructural changes related to PCD were noted at 0 h after TS in Xanthi-nc tobacco tissues as well as in healthy and susceptible tobacco tissues infected with TMV, At 6 h after TS, chloroplasts were convoluted and cytoplasm began to be depleted; however no necrotic cells were found. At 17 h after TS, ground cytoplasm of affected cells was completely depleted and chloroplasts were stacked together with bent cell wall or dispersed in the intracellular space. Necrotic cells were also observed, containing virus particles in the necrotic cytoplasm. There were initially two types of symptoms in the expanded lesions: chlorosis and non-chlorosis (green). Abundant TMV particles and X-bodies were only found in the chlorotic tissue areas. These results suggest that PCD by TMV infection may start with the wilting of cells and tissues before necrotic lesion formation.

Ultrastructural Study on the Salivary Gland of a Korean Freshwater Pulmonate, Radix auricularia coreana

Jeong, Kye-Heon,An, Yong-Hwan The Malacological Society of Korea 1999 The Korean Journal of Malacology Vol.15 No.2

A histochemical and ultrastructural study on the salivary gland of a freshwater snail Radix auricularia coreana was conducted .The epithelial cells of the salivary gland are composed of 9 types of cells. Two types out of them work as frame cells supporting the epithelium and the secretory cells embedded within the epithelium Seven types of secretory cells are classifiable depend on their histochemical reactions and ultrastructures. The materials secreted by the secretory cells are neutral mucopolysaccharide, acid mucopolysaccharide, and glycogen.

이마앞겉질을 제거한 흰쥐 중격옆핵내 이마겉질-중격옆핵로 신경연접의 미세구조

송형곤(Hyoung-Gon Song),안의태(E-Tay Ahn),고정식(Jeong-Sik Ko),박경호(Kyung-Ho Park) 대한해부학회 2003 Anatomy & Cell Biology Vol.36 No.5

성격형성, 순간기억, 인지력, 감정깊이 조절기능들과 관련이 있는 이마앞겉질에서 보상, 욕구, 중독, 기대감 등과 관련이 있는 중격옆핵으로 들어오는 신경연결을 확인하고 연접형태의 미세구조를 밝히고자 이 연구를 시행하였다. 체중 250~300 g 정도의 흰쥐를 실험동물로 하였으며, 이들을 정상군, 대조군, 실험군으로 구분하여 실험하였다. 실험군 동물은 sodium pentobarbital로 마취하여 뇌정위고정대에 고정시킨 후 한쪽 이마뼈에 구멍을 만들고 이마앞겉질을 흡인하여 제거하였으며, 2일 후 희생시켜서 1% paraformaldehyde와 1% glutaraldehyde 고정액으로 관류고정시켰다. 뇌에서 중격옆핵을 punching하여 관류고정액에서 다시 고정한 후, 2% osmium tetroxide액에서 이차고정을 시행하였다. Araldite에 포매하였고 미세절편은 4% uranyl acetate와 2.7% lead citrate로 이중 염색하였으며, JEOL 100CX-II 전자현미경으로 관찰하였다. 관찰결과, 대조군 중격옆핵의 미세구조는 정상군과 차이를 보이지 않았다. 실험군의 중격옆핵에서는 신경그물의 구조에 상당한 변화를 보였는데, 가장 뚜렷한 변화를 보인 것은 퇴행된 축삭종말들로서 축삭가지돌기연접(axodendritic synapse)과 축삭가시연접(axospinous synapse)을 이룬 것들 가운데 일부였다. 퇴행중인 축삭종말들 외에도 아교세포의 세포질돌기들이 확장하여 퇴행구조들을 분리시키면서 용해시켰고, 퇴행종말과 연접했던 가지돌기나 가지돌기가시 안에는 많은 티끌 같은 물질들이 흩어져 있었다. 특히 퇴행종말과 연접했던 가지돌기가시들이 가지돌기 속으로 퇴축되면서 가지돌기들이 팽대현상을 보였다. 이와 같은 변화는 이마앞겉질에서 중격옆핵으로 들어온 축삭종말들이 퇴행하면서 일어나는 병리적 진행과정으로 신경학적 실험에서 흔히 관찰되는 것이었다. 따라서 대뇌 이마앞겉질에서 중격옆핵으로 정보를 보내는 신경섬유의 종말은 가시돌기세포 (spiny cell)의 가지돌기 (dendrite)와 가지돌기가시(dendritic spine)에 연접하는 것이 밝혀졌다. Prefrontal cortex is called psycological cortex, since it deals with making up of individual personality, regulation of personal depth of feeling, working memory, planning, maintaining attention, etc. Whereas, nucleus accumbens (septi) is called the center of reward and motivation or the center of pleasure, since it deals with feeding, drinking, sex, exploration, appetitive learning, drug addiction, etc. Present study was aimed at the proving the prefronto-accumbens input ultrastructurally. Sprague Dawley rats anesthetized with sodium pentobarbital and were removed their prefrontal cortex with suction instrument. Two days following the operation, heads of rats were fixed by perfusion of with 1% glutaraldehyde-1% paraformaldehyde solution via left ventricle. Peristaltic pump was used during perfusion. Two hours later, brains were removed and refixed for 24 hours in the refrigerator, and small tissues of the nucleus accumbens were punched out with punching needle. Tissue blocks were fixed in 2% osmic acid for 2 hours and were embedded in araldite mixture. Ultrathin sections stained with uranyl acetate-lead citrate solution were observed with JEOL 100 CX II electron microscope. In the nucleus accumbens, some axodendritic terminals and axospinous terminals were found degenerated, and volume of activated glial cytoplasm was increased. The degenerated terminals were seen isolated from intact structures by activated glial processes and removed by glial cytoplasm. The result confirms that axon terminals coming from prefrontal cortex input to the spiny neurons of nucleus accumbens septi, on their dendrites and/or dendritic spines.

Ultrastructures of Oocyte Development and Electrophoretic Patterns of the Yolk Protein Following HCG Treatment in Korean Native Catfish (Silurus asotus)

Yoon, J.M.,Chung, E.Y.,Kim, G.W. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.2

During the rapid phase of gonadal development of the freshwater teleost, the catfish (Silurus asotus), the influence of hCG upon the inducement of final oocyte maturation and spawning was investigated electrophoretically and ultrastructurally. The electrophoretic patterns obtained were different in the presence and absence of some of the major or minor zones, because of the hormone level in catfish. The vitellogenin of hormone-treated fish was stained more intensively than that of sham-treated fish. These proteins showed some minor or main bands of egg extracts which migrated at positions corresponding to molecular weights of approximately 90,000. However, the thickness of electrophoretic band in molecular weight for hCG-treated fish was slightly lower than that for saline control. It seemed the plasma protein with molecular weight of approximately 45,000 in hCG-treated fish disappeared. In contrast to the control fish, the ovaries in the catfish treated with hCG shows a marked ultrastructural change under the electron microscope. No dilated profiles were seen in the granulosa cells of the mature oocyte before ovulation. After germinal vesicle breakdown (GVBD), the zona radiata interna (ZRI) becomes more compact, and there is a loss of all the processes from the pore canals. There is a wide space between the vitelline membrane and zona radiata. Also, during final maturation, the microvillar processes from the oocyte are seen no longer to penetrate deeply into the extracellular spaces of the overlying granulosa cells, and the reticulate patterns of the zona radiata interna becomes occluded, giving the zona radiata a more solid appearance. It has been possible to initiate 100% oocyte maturation in yolk granules and follicles in vivo by treatment with hCG and a high water temperature ($27^{\circ}C$). In hCG-treated fish, the percentages of successful artificial fertilization and hatching were maximal at 15 h after a single injection. It seems clear that a long acting preparation containing hCG can be successfully used in prespawning fish to advance the final events of gonadal maturation and initiate spawning. Further studies are necessary to evaluate the potential of hCG to either stimulate or inhibit the reproductive development of fish at other stages of the seasonal reproductive cycle.

Eggshell apex abnormalities associated with Mycoplasma synoviae infection in layers

전은옥,Jong-Nyeo Kim,Hae-Rim Lee,Bon-Sang Koo,Kyeong-Cheol Min,Moo-Sung Han,Seung-Baek Lee,Yeon-Ji Bae,Jong-Suk Mo,Sun-Hyung Cho,Chang-Hee Lee,모인필 대한수의학회 2014 Journal of Veterinary Science Vol.15 No.4

Eggs exhibiting eggshell apex abnormalities (EAA) wereevaluated for changes in shell characteristics such asstrength, thickness, and ultrastructure. Mycoplasmasynoviae (MS) infection was confirmed by serological assayalong with isolation of MS from the trachea and oviduct. Changes in eggshell quality were shown to be statisticallysignificant (p < 0.01). We also identified ultrastructuralchanges in the mammillary knob layer by Scanning ElectronMicroscopy. While eggs may seem to be structurally sound,ultrastructural evaluation showed that affected eggs do notregain their former quality. In our knowledge, this is the first report describing the occurrence of EAA in Korea.