• The Korean Journal of Pain
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• v.11 no.1
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• pp.23-29
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• 1998

Background: The present study was conducted to investigate effects of microinjection of bicuculline, GABA-A receptor antagonist, into the brain stem nuclei on the dorsal horn neuron responsiveness in rats with an experimental peripheral neuropathy. Methods: An experimental neuropathy was induced by a unilateral ligation of L5~L6 spinal nerves of rats. After 2~3 weeks after the surgery, single-unit recording was made from wide dynamic range (WDR) neurons in the spinal cord dorsal horn. Results: Responses of WDR neurons to both noxious and innocuous mechanical stimuli applied to the somatic receptive fields were enhanced on the nerve injured side. These enhanced responsiveness of WDR neurons were suppressed by microinjection of bicuculline into periaqueductal gray(PAG) or nucleus reticularis gigantocellularis(Gi). A similar suppression was also observed when morphine was microinjected into PAG or Gi. Suppressive action by Gi-bicuculline was reversed by naloxonazine, ${\mu}$-opioid receptor antagonist, microinjected into PAG whereas PAG-bicuculline induced suppression was not affected by naloxonazine injection into Gi. Gi-bicuculline induced suppression were reversed by a transection of dorsolateral funiculus(DLF) of the spinal cord. Conclusions: The results suggest that endogenous opioids, via acting on GABAergic interneurons in PAG and Gi, may be involved in the control of neuropathic pain by activating the descending inhibitory pathways that project to the spinal dorsal horn through DLF to inhibit the responsiveness of WDR neurons.

• Applied Microscopy
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• v.31 no.3
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• pp.245-256
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• 2001

The morphological characteristics of spermatogenic cells during the spermiogenesis of Paradoxornis webbiana were studied by transmission electron microscope. Spermiogenesis of P. webbiana was divided into ten phase. The chromatin granules became fibrous granules at the Golgi phase, gradually condensed at the cap phases, condensed as a stick at the acrosomal phase, and finally, a perfect nucleus was formed at the maturation phase. The formation of sperm tail began at the early Golgi phase, and completed at the late maturation phase. In particular, the dense materials existed in the sperm neck, which is wedged between the tip of segmented columns and the first mitochondria of the middle piece. The axone in the neck were surrounded by the dense materials. The axonema in spermatozoon contains a 9+2 arrangement of microtubules: 9 doublets, and 2 central single microtubules. Mitochondrial bundles of middle piece were composed of a pair of arms, which surrounded the axone of the middle piece by the $15^{\circ}$ angled-helical structure. The outer membrane of mitochondria were surrounded by microtubules in plasma membrane of the sperm. The undulating membrane had a helical structure, and the sperm plasma membrane was surrounded by undulating membrane.

• Applied Microscopy
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• v.34 no.3
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• pp.179-184
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• 2004

Normal and abnormal morphology of the epididymal spermatozoa in the big white-toothed shrew, Crocidura lasiura were studied with the light and electron microscopy. Normal spematozoa were observed with a few abnormal spermatozoa. This indicates that abnormal morphology is no absolute indicator of infertility. However, the existence of the abnormal spermatozoa is related to infertility. Especially abnormal morphology of the sperm head is definitely associated with infertility. The following types of abnormal head morphology of the epididymal spermatozoa in the wild healthy adults of the C. lasiura were described: 1) Nucleus with lack of condensation of the nucleoplasm 2) Destructed acrosome 3) Folded acrosome and plasma membrane 4) Separation of the acrosome from the nucleus 5) Acrosome with irregular condensation 6) Wrongly located granules of the apical body.

• Applied Microscopy
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• v.29 no.4
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• pp.417-426
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• 1999

The present investigation is designed to provide basic information on fine structure of the skin of the sea bass, Lateolabrax japonicks in relation to study of epidermal change with environmental and physiological change. The skin of the sea bass is divided into the epidermal layer and dermal layer. Epidermal layer consists of supporting cells and unicellular glands. The supporting cells were classified into the superficial cell, intermediated cell and basal cell. Gland cells were classified into the mucous secretory cell and club cell which is more frequently observed. Superficial cell of epidermal layer is squamous or cuboidal and contains well-developed rough endoplasmic reticulum and the surface is covered with numerous microridges. Superficial cells are connected to another cell with membrane interdigitations and desmosomes. Intermediated cell is ovoid and the electron density is higher than the other supporting cells. Basal cell is cuboidal and has a well-developed mitochondria and membrane interdigitation. The mucous secretory cell has a numerous membrane bounded secretory granules. The cytoplasm of club cell is divided into cortex and medullar. The medullar cytoplasm has a nucleus, intracellular organelles and central vacuole, and the cortical cytoplasm has a well-developed tonofilament. Club cells are connected to another cell with well -developed membrane interdigitations and desmosomes.

• Applied Microscopy
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• v.41 no.2
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• pp.117-122
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• 2011

Sperm morphology of Pipistrellus savii velox was examined by transmission electron microscope. The sperm head of P. savii velox was bullet in shape. The sperm head was 3.1 ${\mu}m$ in length, whose posterior 3.0 ${\mu}m$ was occupied by a nucleus with 1.8 ${\mu}m$ in width. The segmented columns were about 14~15 in number. The total number of mitochondrial gyres was 57. Number of 1, 5, and 6 of the outer dense fibers were larger than the others. A fibrous sheath and longitudinal column of the principal piece were evidence, but the fibrous sheath was not seen at the end piece. In the present study, the length of the sperm head of P. savii velox were very shorter than those of other bats.

• Journal of Life Science
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• v.8 no.1
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• pp.51-59
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• 1998

The apoptosis-inducing activity of ursolic acid (UA) was examined in mouse F9 teratocarcinoma cells on the bases of biochemical and morphological characteeristics. UA, pentacyclic trierpene acid, exhibits antitumor activities including inhibition of skin tumorigenesis, induction of tumor cell differentiation and antitumor promotion. Treatment with UA showed that the decrease of cell viability was dose-dependent. UA also induced genomic DNA fragmetation, a hallmark of apoptosis, indicating that the mechanism of UA-induced F9 cell death was through apoptosis. When the morphology of the F9 cells was examined by electron microscopy, the cells treated with UA showed the charcteristic morphological features of apoptosis such as chromatin condensation and nuclear fragmentation. DNA fragmentations by UA were inhibired by cycloheximide, which suggest that de novo protein synthesis was required for DNA fragmentation by UA. Inaddition, the expression of c-jun was increased, but those of c-myc and laminin B1 were decreased during apoptosis induced by UA in F9 cells. These results suggest that UA causes an apoptosis in F9 cells. Further, the increased expression of c-jun may be involved in the UA-induced apoptosis of f9 cells.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1081-1086
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• 2008

QDs-LEDs(quantum dot light emitting device) should contain well-organized arrays of QDs on an electron transport layer. Thin films of CdSe/ZnS core-shell QDs were successfully fabricated on $TiO_2$ substrates by using PDMS stamp and micro contact printing method. 2-Carboxyethylphosphonic acid(CAPO) and 1,6-hexanedithiol(HDT) were employed as molecular linkers in assembling CdSe/ZnS core-shell QDs with high-density and uniform array. The CAPO increased the binding strength between the QDs and the substrates, and the HDT induced the strong inter-particle attractions of assembled QDs. The assembling properties of QDs thin films were characterized by SEM, AFM, optical microscope and photoluminescence spectroscope(PL).

• Korean Journal of Crystallography
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• v.8 no.2
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• pp.75-80
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• 1997

A perovskite relaxor ferroelectrics PMN is used as an important material to investigate the diffusive phase transition phenomena. In this study PMN single crystals were grown and the microstructure were observed. For the growth of PMN single crystals, the spontaneous nucleation technique and the TSSG technique were used. 2-5mm single crystals were grown from PbO self flux and it was observed that only PMN crystals were grown when excess MgO was added over 100% as flux. Single crystals with well developed (001) faces were obtained from PbO-B2O3 flux. single crystals larger than 1 cm were grown from PbO-B2O3 flux by TXXG technique. For higher quality crystals, optimization of the variables such as the rotation speed of seed crystal, the orientation of seed crystal, and cooling rate is needed. With grown crystals, it was confirmed by TEM diffraction pattern of thin plate crystal that the 1:1 ordering of Mg2+ and Nb5+ with small volume exists.

• The Journal of Korean Physical Therapy
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• v.14 no.2
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• pp.145-152
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• 2002

This study was carried out of to determine effects of high voltage pulsed galvanic stimulation on the soleus. target muscle of the sciatic nerve, of white rat two condition. The coditions included normal, and denervated muscle. The histochemical, ultrastructural observations were made. The following results were obtains. 1. The histochemical observations found the inflammatory cells between muscle bundle and muscle fiber since 1-week control group. In addition, nucleus located in the muscle fiber was frequently observed. 2. The experimental group showed a similar phenomenom to the normal muscles in terms of glycogen granules in the 1-week group, where as fiber were not distinguishable in4-weeks group which indicated that the degenerative changes had occured. 3. The NADH-TR reaction showed that the red muscle slightly increased in the 2-weeks group, and the distinguished was impossible the red fiber 4. The ultrastructures of the muscles in both groups were severely bend, and a number of vacuoles were observed due to the destruction of mitochondria..

• Applied Microscopy
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• v.30 no.4
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• pp.377-387
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• 2000

There are a few tanycytes between the general ependymal cells lining the ependymal layer of the brain ventricle. These cells are considered as modified ependymal cells which possess a long basal process. Tanycytes are known to have an ability to communicate by absorbing substances from cerebrospinal fluid and transporting them to the blood vessels and/or to the neurons in the CNS. The third and fourth ventricular tanycytes were mainly studied as subjects but it's rare to find reports about the tanycytes of the area postrema. Glial fibrillary acidic protein is an intermediate filament protein that is expressed especially in astrocytes of the CNS. But GFAP is also found in filament of the tanycytes and its process. Therefore this study was carried out for the examination of the GFAP immunoreactive tanycytes lining the area postrema of the bat, and we also examined the ultrastructure of tanycytes using electron microscope. GFAP immunoreactive tanycytes were located in the caudal portion of the fourth ventricle, and especially mainly in the transitional zone between the floor of the caudal fourth ventricle and ependymal layer lining the area postrema. A few GFAP immunoreactive tanycytes were also found in the ependymal layer lining the area postrema, and some groups of tanycytes were found in the ependymal layer of the area postrema near the floor of the caudal fourth ventricle , The processes of tanycytes were stained deeply with anti-GFAP antibody. Especially the GFAP immunoreactive tanycytes lining the area postrema had very long processes that cross the whole width of the area postrema. In the electron microscope, the cell body of ependymal tanycyte was located on the ependymal layer and had a long basal process. Intermediate filaments were observed around the nucleus and well developed in the process of tanycrte. Longitudinal oriented long mitochondria and a few lipid droplets were also found in this process. After immunocytocheical staining, the gold particles were found only in the intermediate filaments. We could not determine the function of the tanycytes in the area postrema. Thus, further investigation is required to determine the functional relationship between the tanycytes and the area postrema in hibernating animal, the bat.