• Restorative Dentistry and Endodontics
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• v.25 no.4
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• pp.606-618
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• 2000

Dental pulp infection is most commonly caused by extensive dental caries, and some bacterial species invade root canals; bacterial components and products are thought to be associated with the pathogenesis of periapical periodontitis. A principle driving force behind pulpal disease response appears to lie in the host immune system's to bacteria and their products. We examined the production of interleukin $1{\beta}$ (IL-$1{\beta}$) and tumor necrosis factor ${\alpha}$(TNF-${\alpha}$) from human peripheral mononuclear cells, lymphocytes and monocytes stimulated by heat-killed Acitnobacillus actinomycetemcomitans (ATCC 29523), Porphyromonas gingivalis (ATCC 33277) and Prevotella intermedia (ATCC 25611), and also by their sonicated bacterial extracts (SBE), respectively. The effects of three strains of heat-killed bacteria and their SBEs on the morphology of cultured blood cell lines HL-60 (KCLB 10240) and J774A.1 (KCLB 40067) were observed under the inverted microscope. Ultrastructural changes of J774A.1 exposed to heat-killed P. intermedia and its SBE were investigated using transmission electron microscopy. Production of IL-$1{\beta}$ was reduced in human peripheral mononuclear cells after stimulation by sonic bacterial extracts of A. actinomycetemcomitans, P. gingivalis, and P. intermedia. Heat-killed and sonic extract of P. gingivalis inhibited the production of TNF-${\alpha}$ in peripheral mononuclear cells. Production of TNF-${\alpha}$ was inhibited in peripheral monocytes after stimulation by sonic extracts of A. actinomycetemcomitans, P. gingivalis, and P. intermedia. HL-60 and J 774A.1 cells showed granular degeneration after treatment with heat-killed and sonic extracts of A. actinomycetemcomitans, P. gingivalis, and P. intermedia Chromatin margination and shrinkage were observed in 774A.1 treated with heat-killed P. intermedia. Cell wall structure and organelles were destroyed and vacuoles were formed in cytoplasm in J774A.1 treated with P. intermedia sonic extract. These results suggest that A actinomycetemcomitans, P gingivalis and P intermedia may have an important role in the formation and progression of pulpal diseases via both modulation of production of IL-$1{\beta}$ and TNF-${\alpha}$ from blood mononuclear cells and cytopathic effects.

• Applied Microscopy
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• v.36 no.4
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• pp.291-297
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• 2006

To evaluate the effects of ingestion of alcoholic drinks on the toxicities of industrial compounds, cyclohexane (CH) was intraperitoneally administrated to rats (1.56g/kg body weight), which had been ingested 15% ethanol for up to 6 weeks,4 times by once a day and every other day. Following the last treatment of ethanol or CH, blood and liver tissues were collected after 4 hours prior to sacrifice of animals. By the injection of CH, liver weight (% of body weight) and xanthine oxidase activity in serum were increased, and glucose-6-phasphatase (G6P) activity in liver was decreased compared to them of control group. The activities of CH metabolizing enzymes, such as cytochrome P450 dependent aniline hydroxylase (CYPdAH) and alcohol dehydrogenase (ADH), were significantly increased by injection of CH, and those activities were the highest in CH-injected group after pretreated with alcohol. Ultrastructurally. both of alcohol treatment and CH injection induced transforming into the smooth-endoplasmic reticulum from rough-endoplasmic reticulum, the those rate was the highest in case of CH-injection after pretreated with alcohol. From these results, it is suggested that alcohol intake on a level without alcoholic degeneration of hepatocytes could enhance the CH metabolism of liver.

• Applied Microscopy
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• v.39 no.1
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• pp.49-56
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• 2009

In this study, we investigated tensile properties and ultrastructural changes of straight permed hair using the rheometer and the scanning electron microscopy. First, we compared the morphological characteristic between the virgin hair and the straight permed hair after testing tensile strength. Cuticle cells were heavily lifted off in straight permed hair than in the virgin hair. Cuticle cells were separated by the destruction of intercellular membrane complex and no destruction or damage were found in cytoplasm. In the comparative test for tensile characteristic between the virgin hair and the straight permed hair, tensile distance of the straight permed hair was decreased by 24.5% or 3.05 mm than the virgin hair. The tensile strength was decreased by 34.63% or $5.62\;g/cm^2$ and the maximum stress by 34.59% or 56.12 g. As a result, the tensile property dropped to the lowest level with the straight permed hair than with the bleached hair or the permanent dyed hair of previous studies.

• Applied Microscopy
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• v.21 no.1
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• pp.63-76
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• 1991

Butylated hrdroxyanisole(BHA), a widely used food additive phenolic antioxidant, is known to inhibit cancer formations inducible with a wide variety of chemical carcinogens including aflatoxin $B_1(AFB_1)$. Thus, in the present study morphological characteristics underlying the hepatoprotective effects of BHA against $AFB_1$ inducible ultrastructural changes of hepatocytes have been examined. The obtained results are as follows : 1 . Livers obtained from rats treated with $AFB_1$ in vivo have been examined with transmission electron microscope. Among the many hepatocellular structural aberrations induced by $AFB_1$ treatment, the nuclear chromatins were found to be distributed irregularly('cap formation') and the nuclear membrane was found to be partially segregated. Furthermore, there were many lipid droplets, hyperplasia of smooth endoplasmic reticulum, dialated rough endoplasmic reticulum and, lysosomes arrested at various stages of its development. 2. Also, when $AFB_1$ was given in vitro to hepatocytes which have been isolated from untreated normal rats and examined under scanning electron microscope, there were much 'blobbing' phenomena resulting from cytoskeletal disturbances. 3. However, in the liver obtained from rats pretreated with BHA and then give the $AFB_1$, the observed morphological aberrations were in much reduced extent. Similarly, the BHA-hepatocytes had much decreased severity in the $AFB_1$ inducible blob formations.

• Applied Microscopy
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• v.18 no.1
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• pp.60-76
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• 1988

Chick embryos which have received a single injection of the organophosphate compound, malathion (0.1 mg/0.05 ml, 0.5 mg/0.05 ml, 1.0 mg/0.05 ml or 2.0 mg/0.05 ml) via the yolk sac at certain times (2 days, 4 days or 6 days after incubation) have been investigated. After 9 days of incubation, chick embryos were harvested to examine the effects of malathion on the ultrastructure and the acetylcholinesterase(AChE) activity of the developing spinal cord. The effects of simultaneous injection of malathion and nicotinamide were also compared. On ultrastructural findings, neurons in the ventral horn of spinal cord showed to be inhibited in their differentiation by malathion; nuclear irregularity, separation of nuclear membranes, reduction of ribosomal distribution, and cytoplasmic vacuoles were observed. In the younger embryos treated with relatively high doses of malathion, nucleus and cytoplasmic organelles of neurons were severely destroyed, and the neurons were shown to be necrotic. On cytochemical study of AChE by electron microscope, the positive reaction products of AChE were localized at the membranes of nucleus and endoplasmic reticulum of neurons. Inhibition of AChE activity was severe in groups treated with relatively low doses of malathion. Nicotinamide (5.0 mg/0.05 ml) alleviated malathion-induced morphological alterations. In conclusion, it is suggested that malathion changes the ultrastructure and reduces. AChE activity in differentiating neurons, and the severity of which is consistently dose- and age-dependent.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.4
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• pp.479-491
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• 1998

In order to know the pathogenesis of adult respiratory distress syndrome (ARDS) in association with the oxidative stress by neutrophils, the role of platelet activating factor (1-0-alkyl-2-acetyl-snglycero-3-phosphocholine, PAF) was investigated during acute lung injury induced by interleukin- $1{\alpha}$ (IL-1) in rats. An insufflation of IL-1 into the rat's trachea increased the acetyltransferase activity in the lung and the increase of PAF content was followed. As evidences of acute lung injury by neutrophilic respiratory burst, lung leak index, myeloperoxidase activity, numbers of neutrophils in the bronchoalveolar lavage fluid, neutrophilic adhesions to endothelial cells and NBT positive neutrophils were increased after IL-1 treatment. In addition, a direct instillation of PAF into the trachea caused acute lung leak and the experimental results showed a similar pattern in comparison with IL-1 induced acute lung injury. For the confirmation of oxidative stress during acute lung leak by IL-1 and PAF, a histochemical electron microscopy was performed. In IL-1 and PAF treated lungs of rats, the deposits of cerrous perhydroxide were found. To elucidate the role of PAF, an intravenous injection of PAF receptor antagonist, WEB 2086 was given immediately after IL-1 or PAF treatment. WEB 2086 decreased the production of hydrogen peroxide and the acute lung leak. In ultrastructural study, WEB 2086 mitigated the pathological changes induced by IL-1 or PAF. The nuclear factor kappa B (NFkB) was activated by PAF and this activation was inhibited by WEB 2086 almost completely. Based on these experimental results, it is suggested that the PAF produced in response to IL-1 through the remodeling pathway has the major role for acute lung injury by neutrophilic respiratory burst. In an additional experiment, we can also come to conclude that the activation of the NFkB by PAF is thought to be the fundamental mechanism to initiate the oxidative stress by neutrophils causing release of proinflammatory cytokines and activation of phospholipase $A_2$.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.357-366
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• 1996

The present experiments aimed to investigate the metabolism of calcium during oocyte maturation in rat. The concentration of free calcium and calmodulin in oocytes was measured respectively by using of fluo-3/AM and FITC with microscope fluorescence spectrometer. The ultrastructural localization of calcium precipitates in oocytes was observed with the transmission electron microscope. Cumulus-free immature oocytes(GV-oocyte) were cultured in vitro through 15 hours. The free calcium concentration in GV oocyte was $55.9{\pm}3.5nM$. In calcium-containing medium, the free calcium concentration was increased in germinal vesicle breakdown(GVBD) oocyte($64.2{\pm}7.3nM$). In normal medium after calcium chelator treatment ($10{\mu}M$ BAPTA/AM), the free calcium contents were slightly lower than those in control group. In calcium-free medium, the free calcium content was drastically increased in GVBD($72.7{\pm}3.4nM$) and metaphase I - anaphase I ($88.0{\pm}3.4nM$) oocyte. In maturation rate of oocytes, GVBD rate was high in control group($82.9{\pm}6.55%$) and calcium chelator treatment group($91.2{\pm}4.4%$), but in calcium-free medium group, it was low and then the oocyte was degenerated without polar body formation. Relative content of calmodulin in oocyte was significantly(P<0.001) increased in metaphase I - anaphase I than in GV and GVBD oocyte. The calcium precipitates were observed in mitochondria and cytoplasm of GV oocyte but that were not observed in mitochondria of GVBD and metaphase I - anaphase I oocyte. And then the calcium precipitates reappeared in mitochondria of metaphase II oocyte. The above results indicate that changes in free calcium and calmodulin concentration of oocyte occur according to the maturational stages and the extracellular calcium is required during oocyte maturation. Also change of calcium localization in oocyte occurs according to the maturational stages.

• The Korean Journal of Malacology
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• v.20 no.1
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• pp.17-26
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• 2004

In present study, attempts were made to preserve abalone (Haliotis discus hannai) sperm in liquid form at low temperature, to evaluate the effect of various diluents in short-term storage on sperm, and cryopreservation procedures were optimized for the cryoprotectants and freezing rates, as well as the motility, survival rate, and the ultrastructural changes of sperm after short-term storage and cryopreservation were observed. The abalone sperm reached maximum motility until about 4 min after activation. The motility was constant for about 16 min, after which it dropped gradually, and about 50 min later all motility ceased. In Hanks' balanced salt solution (HBSS, 300 and 400 mOsmol/kg) and 150, 250 and 350 mOsmol/k artificial seawater (ASW), the sperm was immotile. After 100% ASW was added, motility of those sperm, which are in 300, 400 mOsmol/kg HBSS, 250, 350 mOsmol/kg ASW, could be again restored incompletely. Sperm motility can be maintained for 20 days of cold storage only in ASW of 850 and 1200 mOsmol/kg. A high motility index of 3.5-4.5 was observed for the first 8 days in 850 and 950 mOsmol/kg ASW. In other diluents sperm motility was constant less than 10 days, and the motility index was obviously lower than that of sperm in 850 and 1200 mOsmol/kg ASW. After 20 days of cold storage, survival rates of 10.2%-20.7% were obtained in ASW and 300 mOsmol/kg HBSS, and that in 400 HBSS (65.3%) was significantly higher than others. The constant period of sperm motility stored in 850 mOsmol/kg ASW was obviously longer than that in 1200 mOsmol/kg ASW after 6 days of storage. The sperm plunged into liquid nitrogen all died except that sperm using 15% glycerol as cryoprotectant restored 10.4% of motility. The highest motility index (3.4) was obtained with 5% glycerol and freezing procedure: $-50^{\circ}C$/min from $20^{\circ}C$ to $-80^{\circ}C$.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.41-57
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• 1997

This study was carried out to investigate the effect of selenium on the adriamycininduced renal lesions in male Sprague Dawley rats. A total of 60 Sprague-Dawley male rats were divided into 2 control groups(C1: saline, C2: selenium) and 2 treatment groups(T1: adriamycin, T2: adriamycin+selenium). The rats of the C1 and T1 groups were given normal saline(0.15ml/rat), the rats of the C2 and T2 groups were given sodium selenite(0.5mg/kg) intraperitoneally three days a week for 4 weeks. The treatment groups were dosed intraperitoneally with adriamycin(2mg/kg/day) five days at the second week. Animals were sacrificed at the 1st week, 2nd week and 3rd week after dosing with adriamycin. The morphologic abnormalities of the glomeruli and tubules in the kidney of male rats were examined histopathologically and electron microscopically.The results obtained were as follows : The mean body weight of adriamycin dosed group was significantly decreased as compared with that of control group at 4th week(p<0.05). In adriamycin and selenium dosed group, the mean body weight was decreased until the end of 2nd week but gradually increased from 3rd to 4th week. The histopathological findings of the renal corpuscle in adriamycin dosed group were parietal epithelial cell proliferation, vacuolization of glomerulus, and thickened basement membrane of the parietal epithelium. Proximal convoluted tubules were significantly dilated and the lumens were filled with renal cast. These lesions were generally not very significant in the rats given adriamycin and selenium. The electron microscopical findings of the renal glomerulus in the adriamycin dosed group were focal loss and fusion of the pedicels of the podocyte, and some vacuoles in the cytoplasm of the podocytes. There were numerous cytoplasmic vacuoles in the proximal and distal convoluted tubular cells. However, these ultrastructural changes were not significantly observed in the renal tubules of the rats of adriamycin and selenium dosed group. These results suggest that selenium may act as an inhibitor of the renal lesions induced by adriamycin in male rats.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.6
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• pp.456-463
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• 2002

Distraction osteogenesis is a well-established clinical treatment for limb length discrepancy and skeletal deformities. Appropriate mechanical tension-stress is believed not to break the callus but rather to stimulate osteogenesis. In contrast to fracture healing, the mode of bone formation in distraction osteogenesis is primarily intramembranous ossification. Although the biomechanical, histological, and ultrastructural changes associated with distraction osteogenesis have been widely described, the basic biology of the process is still not well known. Moreover, the molecular mechanisms in distraction osteogenesis remain largely unclear. Recent studies have implicated the growth factor cascade is likely to play an important role in distraction. And current reserch suggested that mechanical tension-stress modulates cell shape and phenotype, and stimulates the expression of the mRNA for bone matrix proteins. This article presents the hypotheses and current research that have furthered knowledge of the molecular biology that govern distraction osteogenesis. The gene regulation of growth factors and extracellular matrix proteins during distraction osteogenesis are discussed in this article. It is believed that understanding the biomolecular mechanisms that mediate distraction osteogenesis may guide the development of targeted strategies designed to improve distraction osteogenesis and accelerate bone healing.