• Journal of Korean Ophthalmic Optics Society
• /
• v.9 no.2
• /
• pp.333-343
• /
• 2004

Impression cytology refers to application of cellulose acetate filter material to the ocular surface to remove the superficial layers of the conjunctival epithelium. The technique is non-invasive, is easy to perform, causes minimal discomfort to the patient, and can be used to follow changes in the conjunctival ocular surface over time. With this method, the morphology of the conjunctival ocular surface can be studied and the degree of squmaous metaplasia assessed. This study was performed to evaluate the conjunctival surface by impression cytology in dry eye patients. A total of 70 students with no contact lens wearing history were recruited. Subjects were required to fill in a McMonnies dry eye symptom questionnaire. The non-invasive tear thinning time(TIT) test of each subject was measured, followed by Schirmer tear test(STI), tear film break-up time(TBUT) tests and Rose-bengal staining were performed as a baseline. Conjunctival epithelial cells from the inferior bulbar conjunctiva were harvested by the impression cytology technique. The specimens collected were labelled and stained with PAS(Periodic Acid Schift)-haematoxylin. The goblet cells and conjunctival epithelial cells were observed under a light microscope of 400x magnification. The specimens were classified according to the Nelson Grading scale which was based on the degree of squamous metaplasia such as changes of goblet cells density, size/form, N:C(nucleus : cytoplasm) ratio. Dry eye patients were observed morphological changes of the epithelial cells, different nuclear alterations, decrease of the goblet cells density. The degree of cytological changes was related to severity of dry eye conditions. When the epithelial cell morphology was graded according to the system described by Nelson, specimens from the control group revealed 91.43% of the eyes to be grade 0 and 8.57% to be grade 1, whereas of the dry eye patients, 20% were grade 0, 42.86% grade 1, 34.29% grade 2 and 2,86% grade 3. Impression cytology represents a non- or minimally invasive biopsy of the ocular surface epithelium with no side effects or contraindications. It has demonstrated to be a useful diagnostic aid for a wide variety of processes involving the ocular surface. This technique is a safe, simple method and may help increase understanding of various ocular surface alterations in dry eye patients.

• Journal of Yeungnam Medical Science
• /
• v.10 no.2
• /
• pp.313-337
• /
• 1993

The aim of this study was to clarify the role of Kupffer cells in the mechanism of endotoxin-induced liver injury. The study on fine structure of Kupffer cells was performed after the injection of endotoxin. The endotoxin(Escherichia coli lipopolysaccharide 026 : B6. 1.5mg/100 g of body weight) was intraperitoneally injected in Sprague-Dewley rats. Animals were sacrificed at 1/4, 1/2, 1, 2, 4, 8, 16, 24, 72 and 120 hours after the injection of endotoxin. Livers were extirpated and processed to be examined by light and electron microscopy. The results obtained were summerized as follows: Early changes observed in liver after endotoxin injection included the increased number and hypertrophy of Kupffer cells, infiltration of neutrophils and presence of fibrin thrombi within the sinusoids. The continuous increase of the Kupffer cells in number with hypertrophy, congestion and infiltration of inflammatory cells within the sinusoids were observed. Hepatocytes showed fatty change and occasional necrosis. At 72 hours the congestion decreased. At 120 hours the number of Kupffer cells was increased, but the morphology of Kupffer cells became similar to that of the control group. The numbers and sizes of primary and secondary lysosomes and amount of euchromatin of Kupffer cells increased. Swellings and increase in number of mitochondria, Golgi complex, smooth endoplasmic reticulum, rough endoplasmic reticulum were evident. Microthrombi were present within the sinusoids. The swelling of rough endoplasmic reticulum and mitochondria, decrease of glycogen particles, fatty change, hypoxic vacuoles, pyknotic nuclei and occasional necrosis were observed in hepatocytes. At 72 hours the number of secondary lysosomes in Kupffer cells decreased. At 120 hours the morphology of Kupffer cells became similar to that of the control group. According to these results, it was postulated that the endotoxin was initially taken up by pinocytosis into Kupffer cells and degraded in secondary lysosomes of activated Kupffer cells. Kupffer cells may play an important role in the defense mechanism of liver during endotoxemia. The dysfunction of Kupffer cells and ischemia by sinusoidal microthrombi may cause liver injury.

• Korean Journal of Animal Reproduction
• /
• v.25 no.1
• /
• pp.71-77
• /
• 2001

This experiment was designed to improve the production efficiency of germ-line chimeric mice from phospholipase C (PLC)-$\beta$3 or peroxiredoxin (Prx) E -targeted ($\Delta$) ES cells by the investigating the manipulation conditions and characteristics of Jl ES cells. Four targeting clones were isolated to investigate the karyotypical and morphological stability prior to injection. All clones ($\Delta$PLC$\beta$-3 C3, $\Delta$Prx II C3, C10 and I5) showed more than 80% euploidism, however, most of $\Delta$PLC$\beta$-3 C3 clones were extensively differentiated compared to the other clones. Nine of 13 $\Delta$Prx II chimeras appeared to have at least 80% chimerism, whereas $\Delta$PLC$\beta$-3 C3 chimeras had 20% chimerism at most. Therefore, the morphological stability of ES cells under stable euploidism might mainly affect the production rate of high-coat chimeric mice. To increase the collection rate of injectable blastocysts (IBs), 5 to 10 week -aged C57BL/6J female mice were sacrificed at 3.5 days post-coitum. Ten week-aged mice were the most optimal IB donors by showing the highest collection rate (2.94/mouse) of injectable blastocysts without increase of non-injectable embryos (0.29/mouse). Foster mothers might be another factor because ICR x C57BL/6J F1 foster mother showed more increased productivity in litter size (2.8 vs. 5.6) and chimera (0 vs. 35.3%) than those of ICR foster mothers. In conclusion, the efficient production of germ-line chimeras mainly depends on the maintenance of ES cell morphology during targeting procedure, and the establishment of manipulation conditions might be a key point to maximize it.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.26 no.2
• /
• pp.189-198
• /
• 2012

Our former study indicated efficacy of apoptotic cell death on animal study by using Egg white combined Chalcanthite (EC). Clinically, bamboo salt is using because of safety. Hence we investigated a toxicity study for determining safety by adding bamboo salt in former materiel. We had two studies: toxicity of EC and of Bamboo salt with egg white combined Chalcanthite (BC). Both were studied in 1-week single and 5-week repeated oral dose toxicity tests on male Imprinting Control Region mice. In EC, doses used in 1 week single oral dose toxicity tests were 0, 0.05, 0.5, 5 and 50 mg/kg/day and 0, 0.01, 0.05, 0.25 and 0.5 mg/kg/day. In BC, doses used by 0, 0.08, 8.3, 83.3 and 166.6 mg/kg/day in single oral dose toxicity and 0, 4.2, 8.3, 41.7 and 83.3 mg/kg/day in repeated oral dose toxicity tests. Their blood and urine were assayed and organ morphology were examined. Mann-Whitney U test and ANOVA tests were used by analysing methods. First, significant increased left renal weight in all groups of EC and BC. Second, increased ALT score was found in EC-S2 and increased relative liver weight was found in EC-S3. In addition, increased relative weight and urine bilirubin and urobilinogen were found in EC-R2 and EC-R3. There was no significant toxic change in BC. The Mixture of EC had a possibility of hepatotoxicity in the short and long term. Processed BC appears to be safe and non-toxic in these studies and a no-observed adverse effect level (NOAEL) was established at 83.3 mg/kg/day in mice. Relatively, The BC were safer than The EC.

• Polymer(Korea)
• /
• v.39 no.1
• /
• pp.6-12
• /
• 2015

In order to improve the poor water solubility of aceclofenac, it was loaded into solid Kollidon VA 64 dispersion prepared by spray drying and rotary evaporation methods using different drug and polymer ratios. Morphology and physicochemical behavior of the aceclofenac loaded solid dispersions was analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), and differential scanning calorimetry (DSC). Encapsulation efficiency and dissolution behavior in a simulated intestinal juice of aceclofenac in the solid dispersions was measured using HPLC and the latter was compared with that of the active pharmaceutical ingredient (API) and Airtal$^{(R)}$. It was demonstrated that two methods could significantly improve the dissolution behavior of aceclofenac.

• Journal of Korean Ophthalmic Optics Society
• /
• v.10 no.4
• /
• pp.283-292
• /
• 2005

This study investigated the effects of naringin, and chitosan in rabbits' corneas. Naringin, a glycone of naringenin, is a widely distributed bioflavonoid in the grapefruit and citrus peel, and it has already been reported as an antioxidant, antimicrobial, and anticancer agent. It has been used as a food preservatives and cosmetics. One of the natural preservatives, chitosan has also used in food preservatives, health drinks, and teas. Chitosan is distributed in the epithelium of crustacea, insects, and fungi. Naringin and chitosan have no harmful effects of cytotoxicity in the human body and they are recognized as an antibacterial for various forms of bacteria. The purpose of this study is to search for the ideal percentage of natural products to substitute the chemical preservatives occuring within the cornea and conjunctiva cytotoxicity and inflammations as wearing on soft contact lens. The present study compared the morphology of corneal epithelium and endothelium observed by light microscopy (LM) and transmission electron microscopy (TEM). In vivo methods, We investigated the effects of natural preservatives on soft contact lens. We inserted 3-4 drops of the naringin and chitosan, directly on rabbits' corneas 4 times per a day during one week. After enucleation of cornea, morphorgical damages of the epithelium and endothelium were observed by LM and TEM. In view of ultrastructure, chitosan caused siginficant damage on the epithelium and endothelium of cornea. The damage of cells was higher in chitosan treated cornea than 0.01, 0.1, and 1% of naringin. The 1% of naringin also expressed cell damage seriously. The results suggest that the most important thing is to use the reasonable percentage of preservatives for contact lens solutions.

• Journal of the Korean Electrochemical Society
• /
• v.17 no.2
• /
• pp.94-102
• /
• 2014

Cation exchange membrane (Nafion) was modified to reduce the vanadium ion permeation through the membrane and to increase the vanadium redox flow battery (VRB) system performance by coating the graphene oxide (GO) which has nano-plate like morphology. Modified membrane properties were studied by measuring the ion exchange capacity (I.E.C), water uptake and proton conductivity. The thickness of the coated layer on the surface of the Nafion membrane was observed as $0.93{\mu}m$ by SEM. Proton conductivity and vanadium ion permeability of the modified membrane were decreased to 27% and 25% compared to that of the commercial Nafion membrane respectively. VRB single cell performance test was performed to compare the system performance of the VRB applied with commercial Nafion membrane and modified membrane. VRB system applied with modified membrane showed higher coulombic efficiency and energy efficiency than the VRB system applied with the commercial Nafion membrane due to the reduction of the vanadium ion permeation. From these result, we could suggest that the membrane modification by coating the GO on the surface of the Nafion membrane could be one of the promising strategies to reduce the vanadium ion permeation and to increase the VRB system performance effectively.

• Applied Chemistry for Engineering
• /
• v.21 no.4
• /
• pp.435-439
• /
• 2010

Pt-$MoO_3$ electrodes were fabricated on ITO-coated glass by electrodeposition method using 20 mM hydrogen hexachloroplatinate ($H_2PtCl_6$) and 10 mM Mo-peroxo electrolyte. Deposition order was varied, and catalytic activities of synthesized electrodes were compared with that of pure Pt electrode. Scanning Electron Microscopy (SEM) was utilized to examine surface morphology. The crystallinity of synthesized films was analyzed by X-ray Diffraction (XRD), and the oxidation state of both the platinum and molybdenum were determined by X-ray Photoelectron Spectroscopy (XPS) analyses. The catalytic activity and stability for methanol oxidation were measured using cyclic voltammetry (CV) and chronoamperometry (CA) in a mixture of 0.5 M $H_2SO_4$ and 0.5 M $CH_3OH$ aqueous solution. $MoO_3$ electrodeposited on the surface of Pt showed much higher catalytic acitivity and stability than pure Pt electrode due to the good contact between Pt and $MoO_3$.

• Journal of Life Science
• /
• v.22 no.4
• /
• pp.447-455
• /
• 2012

Akt plays an important role in a variety of cellular physiologies such as growth, proliferation, and differentiation. In skeletal muscle, Akt has been implicated in regulating regeneration, hypertrophy, and atrophy. In this study, the role of Akt has been examined during skeletal muscle differentiation. Culturing C2C12 myoblasts under low serum (1% horse serum) and high density converted cell morphology from a round shape to an elongated and multi-nucleated shape. Morphological changes were initiated from day 2 of differentiation. In addition, the expression of both myogenin G and myogenin D was elevated from day 2 of differentiation. Skeletal muscle differentiation was abolished by silencing Akt1 or Akt2, but was significantly enhanced by the over-expression of either Akt1 or Akt2. The activation of Akt was observed from day 2 of differentiation and disappeared after day 7. The expression of kruppel-like factor 4 was observed from day 6 of differentiation. Moreover, this expression was blocked in cells silencing either Akt1 or Akt2. In addition, the promoter activity of kruppel-like factor 4 was significantly reduced in cells silencing Akt1 or Akt2. These results suggest that Akt regulates skeletal muscle differentiation through the regulation of kruppel-like factor 4 expression.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.59.1-59.1
• /
• 2010

Aluminum-induced crystallization (AIC) of amorphous silicon (a-Si) is studied with the structure of a glass/Al/$SiO_2$/a-Si, in which the $SiO_2$ layer has micron-sized laser holes in the stack. An oxide layer between aluminum and a-Si thin films plays a significant role in the metal-induced crystallization (MIC) process determining the properties such as grain size and preferential orientation. In our case, the crystallization of a-Si is carried out only through the key hole because the $SiO_2$ layer is substantially thick enough to prevent a-Si from contacting aluminum. The crystal growth is successfully realized toward the only vertical direction, resulting a crystalline silicon grain with a size of $3{\sim}4{\mu}m$ under the hole. Lateral growth seems to be not occurred. For the AIC experiment, the glass/Al/$SiO_2$/a-Si stacks were prepared where an Al layer was deposited on glass substrate by DC sputter, $SiO_2$ and a-Si films by PECVD method, respectively. Prior to the a-Si deposition, a $30{\times}30$ micron-sized hole array with a diameter of $1{\sim}2{\mu}m$ was fabricated utilizing the femtosecond laser pulses to induce the AIC process through the key holes and the prepared workpieces were annealed in a thermal chamber for 2 hours. After heat treatment, the surface morphology, grain size, and crystal orientation of the polycrystalline silicon (pc-Si) film were evaluated by scanning electron microscope, transmission electron microscope, and energy dispersive spectrometer. In conclusion, we observed that the vertical crystal growth was occurred in the case of the crystallization of a-Si with aluminum by the MIC process in a small area. The pc-Si grain grew under the key hole up to a size of $3{\sim}4{\mu}m$ with the workpiece.