• Journal of Korean Ophthalmic Optics Society
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• v.13 no.3
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• pp.103-109
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• 2008

Purpose: This review illustrates an importance of oxidative stress caused by reactive oxygen species (ROS) and reactive nitrogen species (RNS) generation in association with eye disease, especially of cataract, and discusses an important role of lipid peroxide as a mediator of oxidative stress-related ocular dysfunction. Methods: Oxidative stress, resulted from the cellular production of ROS and RNS, is known to cause various forms of cellular damages such as protein oxidation, DNA breaks, apoptosis, and lipid peroxidation. These damages can be developed to human diseases. Accumulating evidence strongly suggests that continuous or constant exposure of eye tissues to oxidative stress is a main cause of cataractogenesis. Therefore, we investigated the action of oxidative stress in ocular dysfunction. Results: The ocular lens is continuously attacked by ROS inevitable generated from the process of cellular metabolism and the chronic exposure to ultraviolet. Excessive generation of ROS, resulting in degradation, oxidation, crosslinking and aggregation of lens proteins, is regarded as an important factor in development of cataract. Conclusions: These oxidative stress and oxidant/antioxidant imbalance produces the excess ROS which can lead to eye dysfunction. Even though known results, it should be noted that there is limited information on the molecular mechanism which can be better defined with the interrelation of oxidative stress and optic abnormalities.

• Korean Journal of Veterinary Service
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• v.38 no.3
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• pp.173-180
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• 2015

Environmental pesticides used for insect control can be transferred from plants to animals even to livestock animals through food chain. Human beings also can be exposed to pesticides by consuming polluted dairy products, including meats, eggs and other milk products. Therefore, the Ministry of Food and Drug Safety (MFDS) established Standard for Pesticide Residue Limits in dairy products. The QuEChERS (quick, easy, cheap, effective, rugged and safe) methods for detecting residual pesticides are relatively well established for fruits and vegetables, however, the methods for meat have not been appropriately studied yet. In the present work, pyraclofos was used as an organophosphate pesticide to examine its tissue residue in experimental animals by QuEChERS methods. For this, pyraclofos (150 mg/kg body weight) was orally administered to male rats once a day for 2 days. After 6, 12, and 24 hr of the treatment, the tissue residues in liver and femoral muscle of the rats were determined using QuEChERS methods followed by HPLC analyses. In preliminary studies, the recovery rates of spiking samples of pyraclofos demonstrated approximately 109~110% from the tissues. In previous study, pyraclofos tissue residues were observed with significantly high levels in livers and muscles at 6 hr of oral treatment. Then, they were almost completely disappeared after 24 hr of the administration, indicating the orally exposed pyraclofos is rapidly absorbed and distributed to body organs, then quickly excreted from the body with a negligible level of tissue residue. The alterations in blood chemistry as well as the histopathology of heart, lung, liver, spleen and kidney have also been investigated in the experimental animals for assessing acute toxic effects of pyraclofos. The obtained blood chemistry indexes (ALT and AST) showed maximum peak values at 12 hr after the oral administration and decreased to the normal levels at 24 hr of the treatment. Histopathologic observation exhibited acute hepatic damages at 24 hr of the treatment. In conclusion, we suggest that QuEChERS method can be adequately optimized for the analysis of pyraclofos residues in animal tissues.

• Journal of Life Science
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• v.25 no.5
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• pp.539-547
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• 2015

This study aimed to investigate the protective effect of Semisulcospira libertina extract on liver injury induced by D-galactosamine in rats. After the administration of S. libertina extract, the local fat degeneration and infiltration of inflammatory cells in liver tissues were significantly decreased and peripheral hemorrhages around portal triads and central necrosis around central veins were found to be protective. The elevated levels of plasma ALT, AST, and LDH, the ALP activation lipid peroxidation, and the lipid contents of a damaged liver were recovered in experimental rats administrated with S. libertina extract, suggesting its role in blood enzyme activation and lipid content restoration within damaged rat liver tissues. Moreover, the expression rate of TNF-α, which accelerates inflammation and induces tissue damage and necrosis, was significantly decreased. In addition, the activities of antioxidant enzymes were more effectively upregulated compared to those of the control group induced hepatotoxicity. All data showed that S. libertina extract has a preventive role against liver damages, such as inflammation and tissue necrosis, as instigated with D-galactosamine by improving the activities of blood enzymes and antioxidant enzymes and modulating the expression of inflammation factor, suggest S. libertina extract is an effective medicinal resource for the restoration of hepatotoxicity.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.9-18
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• 2018

Objectives : This study aimed to investigate the anti-ulcer effect of an standardized herbal extracts mixture of Inulae Flos and Paeoniae Radix (HT074) on acidified ethanol induced gastric injury and its potential mechanisms. Methods : Antioxidant activities of HT074 and its constituents were measured by DPPH (2,2-Diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging capacity. After the oral administration of HT074 at doses of 100, 300 mg/kg twice per day for 14 days, Gastric lesions were induced by oral administration of acidified ethanol in Sprague Dawley rats. Oxidative stress markers, such as super oxide dismutase (SOD) activity, concentrations of catalase (CAT) and glutathione (GSH) were measured in gastric mucosal tissues. Additionally, the expression of human mucin gene, Mucin 5AC (MUC5AC) mRNA in gastric mucosal tissues was measured. Results : HT074 showed dose dependent radical scavenging activities against DPPH and ABTS radicals. Oral administration of HT074 300 mg/kg for 14 consecutive days significantly decreased gastric lesions and histological damages induced by HCl/EtOH in rats. HT074 treatment significantly increased the activity of SOD (300 mg/kg) and concentration of GSH (100 and 300 mg/kg), however catalase concentration was not significantly increased. MUC5AC mRNA expression was significantly increased by HT074 100, 300 mg/kg treatment. Conclusions : HT074 protects the gastric mucosa from oxidative stress caused by acidified ethanol by increasing the activity of SOD, concentration of GSH and mucin biosynthesis. These findings suggest that HT074 could be an effective candidate for prevention and treatment of gastritis and gastric ulcer.

• Journal of Korean Neurosurgical Society
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• v.51 no.5
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• pp.247-252
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• 2012

Objective : The anatomical knowledge is the most important and has a direct link with success of operation in cervical spine surgery. The authors measured various cervical parameters in cadaveric dry bones and compared with previous reported results. Methods : We made 255 dry bones age from 19 to 72 years (mean, 42.3 years) that were obtained from 51 subjects in 100 subjects who donated their bodies. All measurements from C3-C7 levels were made using digital vernier calipers, standard goniometer, and self-made fix tool for two different cervical axes (canal and disc setting). We classified into 4 groups (uncinate process, vertebral body, lamina, and pedicle) and measured independently by two neurosurgeons for 28 parameters. Results : We analyzed 23970 measurements by mean value and standard deviations. In comparing with previous literatures, there are some different results. The mean values for uncinate process (UP) width ranged from 5.5 mm at C4 and 5 to 6.3 mm at C3 and C7 in men. Also, in women, the mean values for UP width ranged from 5.5 mm at C5 to 6.3 mm at C7. C7 was widest and C5 was most narrow than other levels. The antero-posterior length of UP tended to increase gradually from C3 to C6. The tip way, tip distance, and base distance of UP also showed increasing pattern from C3 to C7. Conclusion : These measurements can provide the spinal surgeons with a starting point to address bony architectures surrounding targeted soft tissues for safeguard against unintended damages during cervical operation.

• Development and Reproduction
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• v.17 no.4
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• pp.435-440
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• 2013

Previous studies, including our own, have demonstrated that the intratesticular injection of hypertonic saline (20%) decreased serum testosterone level which was similar to the surgical castration in the rat, showing the state of chemical castration. In the present study, we further verify the efficacy of this less invasive method as an alternative of surgical orchidectomy in the andrological field. Sterilized 20% saline was directly injected into the adult male rats (750 ${\mu}l$ per testis). The tested rats were divided into 3 groups including intact group (intact), orchidectomy group (ORX) and saline injection group (SAL) after bilateral orchidectomy was performed at the same day of injection. All rats were sacrificed at 4 weeks after injection. The reproductive organs (testes, epididymis, seminal vesicles and prostates) were collected and used for DNA and protein pattern analyses. Also, patho-histological studies on the testes were performed. In contrast to the intact group, similar DNA damages of testis and seminal vesicle were appeared in ORX group and SAL group. The DNA degradations seemed to be the results of necrosis rather than apoptosis. In the protein pattern analysis, all the testing tissues exerted similar patterns in the ORX group and the SAL group compared to the those of intact group. Patho-histological studies revealed that severe degenerative changes in testicular seminiferous tubules and massive infiltration of immune cells in SAL group. The present study confirmed that direct injection of hypertonic saline into the testis caused the equivalent biochemical changes in the accessory sex organs as shown in the orchidectomized animals. These results suggest that hypertonic saline injection model could be a useful castration model which can substitute for surgical castration when its safety is secured through further study in the future.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.9 no.1
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• pp.39-41
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• 2013

Behavioral problems could be easily observed in patients with various mental disorders, and may be inevitable. Self-injurious behavior(SIB) can be defined as a deliberate or subconscious alteration or destruction of one's body without conscious suicidal intent. SIB frequently involves oral tissues and could vary from a trifling injury to damages that could lead to further disabilities. The cases presented in this report discuss oral SIB due to Tic disorder and ADHD and their treatments. Clinicians should be well aware of the possibility of oral SIB in various mental disorders as well as the diverse depths of such behaviors accordingly. Moreover, different treatment modalities should be prioritized according to the causative mental disorders.

• Journal of Life Science
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• v.23 no.6
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• pp.838-846
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• 2013

As a forth state of material, plasma is ionized gas, which generates characteristically various reactive species. After late of $20^{th}$ century, plasma has been widely used in industry. After nonthermal atmospheric plasma was developed, it has been applied to biomedical fields. Nonthermal atmospheric plasma does not give thermal damages to human tissues, and it shows the high efficiency in cancer treatment, sterilization, tooth bleaching, coagulation, and wound healing. Because the application of plasma to biomedicine has been expanded through interdisciplinary studies, its value of high medical technology is increasing now. Since nonthermal atmospheric plasma was first applied to the mammalian cells and microorganisms, many valuable studies has been performed for about last 10 years, so that now the new research area called 'plasma medicine' has been formed. This article introduces the recent data resulted from plasma medicine and helps to understand the plasma medicine.

• Environmental Mutagens and Carcinogens
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• v.23 no.3
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• pp.99-102
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• 2003

IARC classified areca quid as a human carcinogen. Areca quid chewed in Taiwan includes Piper betle inflorescence, which contains high concentrations of safrole (15 mg/fresh weight). Safrole is a documented rodent hepatocarcinogen, and chewing areca quid may contribute to human exposure (420 $\mu$m in saliva). The carcinogenicity of safrole is mediated through 1'-hydroxysafrole formation, followed by sulfonation to an unstable sulfate that reacts to form DNA adducts. Using human liver microsomes and Escherichia coli membranes expressing bicistronic human P450s, CYP2E1 and CYP2C9 were identified as the main P450s involved in the activation of safrole. We have demonstrated the presence of stable safrole-dGMP adducts in human oral tissues following areca quid chewing using $^{32}$ P-postlabeling and HPLC mass spectrometry methods. By studying 88 subjects with a known AQ chewing history and 161 matched controls, we have demonstrated that the presence of safrole-DNA adducts in peripheral blood cells was correlated to AQ chewing, and CYP2E1 seemed to play an important role in the modulation of safrole-DNA adduct formation. We have also shown that safrole can form stable safrole-DNA adducts as well as oxidative damages in rodent liver. However, the stable safrole-DNA adducts may represent a more significant initial lesion as compared to the rapidly repaired safrole-induced 8-hydroxy-2'-deoxyguanosine. This oxidative DNA damage is mediated through the formation of hydoryxchavicol, the major safrole metabolite in human urine. Hydroxychavicol may have gone through two-electron oxidation to the o-quinone; then via one-electron reduction to semiquinone radicals to generate oxidative DNA damage. However, these reactive metabolites can be efficiently conjugated by GSH. These data suggest that safrole may contribute to the initiation of oral carcinogenesis through safrole-DNA adduct and not oxidative DNA damage. In addition, CYP2E1 may modulate this adduct formation.

• Journal of the Korean Society for Nondestructive Testing
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• v.37 no.2
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• pp.91-98
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• 2017

Recently, composite materials have been mainly used in the main wings, ailerons, and fuselages of aircraft and rotor blades of helicopters. Composite materials used in rapid moving structures are subject to impact by hail, lightning, and bird strike. Such an impact can destroy fiber tissues in the composite materials as well as deform the composite materials, resulting in various problems such as weakened rigidity of the composite structure and penetration of water into tiny cracks. In this study, experiments were conducted using a 2 kW halogen lamp which is most frequently used as a light source, a 2 kW near-infrared lamp, which is used for heating to a high temperature, and a 6 kW xenon flash lamp which emits a large amount of energy for a moment. CFRP composite sandwich panels using Nomex honeycomb core were used as the specimens. Experiments were carried out under impact damages of 1, 4 and 8 J. It was found that the detection of defects was fast when the xenon flash lamp was used. The detection of damaged regions was excellent when the halogen lamp was used. Furthermore, the near-infrared lamp is an effective technology for showing the surface of a test object.