• Journal of Korean Medicine Rehabilitation
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• v.23 no.1
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• pp.1-13
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• 2013

Objectives : The pathophysiology of acute spinal cord injury(SCI) may be divided into primary and secondary mechanisms of injury. The secondary mechanism involves free radical formation, excitotoxicity, inflammation and apoptotic cell death, and sets in minutes after injury and lasts for weeks or months. During this phase the spinal tissue damages are aggravated. Therefore, secondary mechanisms of injury serve as a target for the development of neuroprotective drug against SCI. The present study investigated the effect of tetramethylpyrazine(TMP), an active ingredient purified from the rhizome of Ligusticum wallichii(川芎, chuanxiong), on neuronal apoptosis in spinal cord compression injury in rats. Methods : SCI was subjected to rats by a static compression method(35 g weight, 5 mins) and TMP was treated 3 times(30 mg/kg, i.p.) during 48 hours after the SCI. Results : TMP ameliorated the tissue damage in peri-lesion of SCI and reduced TUNEL-labeled cells both in gray matter and in white matter significantly. TMP also attenuated Bax-expressed motor neurons in the ventral horn and preserved Bcl-2-expressed motor neurons. Conclusions : These results indicate that TMP plays a protective role in apoptotic cell death of neurons and oligodendrocytes in spinal cord injury. Moreover, it is suggested that TMP and TMP-containing chuanxiong may potentially delay or protect the secondary spinal injury.

• Bulletin of the Korean Chemical Society
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• v.8 no.2
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• pp.96-101
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• 1987

2-Ethoxy-6-methoxy-5-cyano-3,4-dihydro-2H-pyran (1_a$), 2-n-butoxy-6-methoxy-5-cyano-3,4-dihydro-2H-pyr an (1b), 2-isobutoxy-6-methoxy-5-cyano-3,4-dihydro-2H-py ran ($1_c$), and 2-ethoxy-6-methoxy-3-methyl-5-cyano-3,4-dihydro -2H-pyran ($1_d$) were prepared by (4 + 2) cycloaddition reaction of methyl $\alpha$-cyanoacrylate with the corresponding alkyl vinyl ethers. Compounds $1_{a-d}$ were ring-open polymerized by cationic catalyst to obtain alternating head-to-head (H-H) copolymers. For comparison, head-to-tail (H-T) copolymer $3_a$ was also prepared by free radical copolymerization of the corresponding monomers. The H-H copolymer exhibited minor differences in its $1_H% NMR and IR spectra, but in the $^{13}C$ NMR spectra significant differences were observed between the H-H and H-T copolymers. Glass transition temperature ($T_g$) of H-H copolymer was higher than that of the H-T copolymer, but thermal decomposition temperature of the H-H copolymer was lower than that of the H-T copolymer. Compounds $1_a$, $a_b$, and $1_c$, copolymerized well with styrene by cationic catalyst, but compound 1d failed to copolymerize with styrene. All of the H-H and H-T copolymers were soluble in common solvents and the inherent viscosities were in the range 0.2-0.4 dl/g.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.379-388
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• 2013

Diabetic nephropathy is one of the serious complications in patients with either type 1 or 2 diabetes mellitus but current treatments remain unsatisfactory. Results of clinical research studies demonstrate that Panax ginseng can help adjust blood pressure and reduce blood sugar and may be advantageous in the treatment of tuberculosis and kidney damage in people with diabetes. The heat-processing method to strengthen the efficacy of P. ginseng has been well-defined based on a long history of ethnopharmacological evidence. The protective effects of P. ginseng on pathological conditions and renal damage associated with diabetic nephropathy in the animal models were markedly improved by heat-processing. The concentrations of less-polar ginsenosides (20(S)-Rg3, 20(R)-Rg3, Rg5, and Rk1) and maltol in P. ginseng were significantly increased in a heat-processing temperature-dependent manner. Based on researches in animal models of diabetes, ginsenoside 20(S)-Rg3 and maltol were evaluated to have therapeutic potential against diabetic renal damage. These effects were achieved through the inhibition of inflammatory pathway activated by oxidative stress and advanced glycation endproducts. These findings indicate that ginsenoside 20(S)-Rg3 and maltol are important bioactive constituents of heat-processed ginseng in the control of pathological conditions associated with diabetic nephropathy.

• Nano
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• v.13 no.11
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• pp.1850127.1-1850127.13
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• 2018

Bi metal deposited on $Bi_2MoO_6$ composite photocatalysts have been successfully synthesized via a simple reduction method at room temperature with using $NaBH_4$ as the reducing agent. The photocatalytic activity of the composite was evaluated by degradation of rhodamine B (RhB) and bisphenol A (BPA) solution under visible light. The rate constant of $Bi/Bi_2MoO_6$ composite to RhB is 10.8 times that of $Bi_2MoO_6$, and the degradation rate constant of BPA is 6.9 times of that of $Bi_2MoO_6$. Nitrogen absorption-desorption isotherm proved that the increase of specific surface area is one of the reasons for the improvement of photocatalytic degradation activity of $Bi/Bi_2MoO_6$ composites. The higher charge transfer efficiency of $Bi/Bi_2MoO_6$ is found through the characterization of the photocurrent and impedance, which are attributed to the surface plasmon resonance (SPR) effect produced by the introduction of the metal Bi monomer in the composite. Free radical capture experiments proved that cavitation is the main active species. Based on the above conclusions, a possible mechanism of photocatalytic degradation is proposed.

• The Korea Journal of Herbology
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• v.38 no.6
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• pp.29-44
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• 2023

Objectives : This study was planned to evaluate the therapeutic effectiveness and possible underlying mechanism of TPE (Tetrapanax papyrifer stem(inner part of the stem Extract) and AQE (Akebiae quinata stem Extract) on osteoarthritis. Methods : Osteoarthritis models were induced through intra-articular injection of MIA (monosodium iodoacetate) 50 μL with 80 mg/ml in rats. Excluding the normal group, Osteoarthritis-induced rats were divided into 4 groups (Control, INDO, TPE, AQE). The drug concentrations were indomethacin 5 mg/kg, TPE 200 mg/kg, and AQE 200 mg/kg, and were orally administered once a day for a couple of weeks. After drug supplementation, the effects of TPE and AQE were measured with serum diagnosis, western blotting, and histopathological staining. Results : It was found that the DPPH and ABTS free radical erasure ability of AQE was better than that of TPE. AQE administration improved rear limb overload and it led to relieving pain. Both PTE and AQE significantly reduced the expression of inflammatory mediators COX-2, iNOS, and inflammatory cytokine IL-1β and IL-6 by inhibiting the phosphorylation of IκBα and deactivating the pathway of NF-κBp65. On the other hand, TNF-α was significantly reduced only by administration of AQE. In addition, histopathological analysis showed that the administration of AQE compared to PTE suppressed cartilage degeneration and effectively suppressed damage to proteoglycan, a component of ECM. Conclusion : Reviewing these experimental results, TPE and AQE possessed the effect of delaying the progress of osteoarthritis and protecting cartilage. In addition, the results of this study show that AQE has a better cartilage protection effect than TPE.

• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.319-327
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• 1994

Background: The pathogenetic mechanism of adult respiratory distress syndrome(ARDS) is not clearly defined yet, but it is well known that increased pulmonary capillary permeabilty is characteristic feature of ARDS. The increased alveolar-capillary permeability is usually preceded by damage of pulmonary artery endothelial cells. The released enzymes and oxygen free radicals from the activated neutrophils seem to play a predominant role in endothelial cell cytotoxicity. The activated neutrophils, however, probably are not the sole contributing factor in this type of damage because many cases of ARDS have been reported in severe neutropenia. Bacterial endotoxin perse and/or oxygen free radicals released from endothelial cells are suggested to be possible factors that contribute to the development of ARDS. The purpose of this study is to investigate the direct cytotoxicity of endotoxin and the role of oxygen free radicals released from the endothelial cells in endotoxin-induced endothelial cell cytotoxicity. Methods: First, to investigate whether endotoxin is cytotoxic to HUVE by itself, various doses of endotoxin were added to culture medium and cytotoxicity was measured. Second, to evaluate the possible role of oxygen free radical in endotoxin-induced HUVE cytotoxicity, various antioxidants were added on the endotoxin-induced HUVE cytotoxicity and cytotoxicity was measured. Third, to verify the release of oxygen free radicals from HUVE, the concentrations of hydrogen peroxide in the endotoxin-treated culture supernatant were measured. Finally, to observe the cytotoxic effect of hydrogen peroxide, HUVE cytotoxicity in the presence of various doses of hydrogen peroxide was measured. The fourth generations of subcultured HUVE from primary culture were used. The cell cytotoxicity was quantified by the chromium-51 release assay. Results: 1) Endotoxin alone showed HUVE cytotoxicity in a dose-dependent fashion. 2) Endotoxin-induced HUVE cytotoxicity was significantly attenuated by the pretreatment of catalase and DMTU. 3) Hydrogen peroxide was released from HUVE after endotoxin treatment in a dose-dependent fashion. 4) Exogenous hydrogen peroxide also showed HUVE cytotoxicity in a dose-dependent fashion. Conclusion: These results suggest that endotoxin alone can directly injure HUVE, and, oxygen-free radicals released from HUVE in response to endotoxin may also participate in the endotoxin-induced HUVE cytotoxicity.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.2
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• pp.49-59
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• 2002

The main function of plastic materials in food packaging is to preserve a food for safe transportation and storage. The interactions between food and plastic materials in food packaging have become increasingly important for food quality and safety because monomer, low molecular weight components, or additives of plastic packaging materials can migrate into a food. The use of antioxidants in plastic materials can help protect the degradation of film itself and retard the oxidation of a packaged food containing lipid, through the migration of antioxidant from the packaging to a product via an evaporation / sorption mechanism. Nowadays, antioxidant (BHT) impregnated plastic materials are used for commercial food packaging application with the intention of achieving an extended shelf life of food in USA. Alpha tocopherol, as one of the most important free radical scavengers, has been well known in biological systems. Moreover, the potential use of alpha tocopherol as an additive for polymers used in the packaging industry may offer the most positive perception from both consumers and manufacturers. Alpha tocopherol has been used as an antioxidant for polyolefin resins fabricated to both bottles and film and has applications in the food packaging industry as a replacement for BHT. Today, alpha tocopherol offers an attractive choice for use as an antioxidant in polymers. This paper provides an overview of antioxidant effectiveness and applications for its use by the food packaging industry based on the evaporation-sorption mechanism of a packaging model product, where quality is associated with lipid oxidation. Important analytical techniques for predicting antioxidant interaction between the package system and product are discussed.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.259-265
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• 2006

This study is investigated the effect on mechanism of nephrotoxicity formation of methotrexate(MTX) by hyperglycemic by streptozotocin(STZ). MTX was injected daily at two doses of 3, 6 mg/kg for 1 week in STZ-induced hyperglycemic rats. Activities of BUN, creatinine and LDH were significantly increased by treatment with MTX in STZ-induced diabetic group when compared to MTX treatment group in normal rats' Renal lipid peroxide content and activities of cytosolic enzyme were significantly increased in the treatment of MTX in diabetic group. The concentration of glutathione and glutathione biosynthesis enzymes were decreased by treatment with MTX in STZ-induced diabetic group. These results suggest that nephrotoxicity of MTX in STZ-induced hyperglycemic rat was caused by activation of renal metabolizing enzymes in cytosol and decrease of glutathione concentration.

• Journal of Ginseng Research
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• v.26 no.3
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• pp.139-144
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• 2002

Pregnancy is a physiological state accompained by a high energy demand of many bodily functions and an increased oxygen requirement. Because of the increased intake and utilization of oxygen, increased levels of oxidative stress would be expected. So we observed the activities of the hepatic antioxidant enzymes from rat treated with total saponin from the red ginseng against free raicals produced in pregnant rats. The activity of superoxide dismutase (SOD) in the control group was slightly decreased during pregnancy, and SOD activity in total saponin treated group was not observed any siginificant change compared with the control group. The activities of glutathione peroxidase (GPX), glutathione reductase (GRD) and catalase in the control group have shown the decreasing tendency during pregnancy, whereas the activities of GRD and catalase in total saponin treated group showed significant increased tendency compared with the control group. GPX activity in total saponin treated group was slightly decreased tendnency compared with the control group. The activity of glutathione-S-transferase (GST) in the control group was increased to keep the state of homaeostasis tendency in pregnant rats. On the other hand, the activity of GST after total saponin treatment was increased than control group. Activity of all enzymes in the control group and total saponin treated group recovered the normal level after delivery of rats. In spite of the physiological changes in vivo, the inflaunce of total saponin on activaties of hepatic antioxidant enzyme in pregnant rats seems to be regulated the biological homeostatic adaptation mechanism which protects the maternal liver aganist oxygen induced toxicity

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.423-430
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• 2003

The teeth bleaching with bleaching agent is widely used at recent times. Until yet the exact mechanism of the bleaching agent isn't known but it is thought that is by the complex reduction-oxidation reaction of the decomposed free radical from bleaching agent through various ways. In other words, it is supposed that the teeth are whitened by agent's changing chemical structures of stain-causing materials. The purpose of this study is to exam the change of the dentinal character by bleaching agent and to evaluate the safety of this agent. For this study, after applying 10% carbamide peroxide to enamel of human premolar for 6 hours a day for 2 weeks we examined changes of surface morphology, microhardness, composition and contents of minirals in human dentin using SEM, microhardness tester, FT-Raman spectrometer and EPMA and got following results. There was no significant difference in surface morphologic change when we examined the effect of 10% carbamide peroxide which penetrated into dentin after applied on enamel surface comparing with result from specimen in distilled water No change was shown on the surface of peritubular and intertubular dentin within the nanometeric range. The microhardness between bleached teeth and teeth stored in distilled water showed no statistically significant difference FT-Raman spectra of dentin exhibited no change of the component in human dentin. Only the least change in peaks of organic and inorganic materials were detected in Raman intencity. The total content of mineral elements in dentin with no treatment, stored only in distilled water and stored in distilled water after bleaching were $98.73{\pm}1.89,\;98.56{\pm}2.11\;and\;97.47{\pm}2.51$ respectively. Also they showed no statistically significant difference. From above results, the effect of 10% carbamide peroxide bleaching on structure of dentin is very low and the results may confirm the safety of this bleaching agent.