• BMB Reports
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• v.36 no.4
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• pp.373-378
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• 2003

Effects of L-arginine and NG-nitro-L-arginine methyl ester (L-NAME) on the renal dysfunction that is induced by cisplatin (CDDP) were investigated. A single dose of CDDP (7.5 mg/kg i.p.) induced renotoxicity, which was manifested by increasing the sensitivity of isolated urinary bladder rings to acetylcholine (ACh), together with a significant elevation of serum urea and creatinine, and a severe decrease in serum albumin. Moreover, renal dysfunction was further confirmed by a significant decrease of enzyme activities, such as glutathione peroxidase, GSH-Px (E.C 1.11.1.9), catalase (E.C 1.11.1.6), as well as a significant increase in lipid peroxides that were measured as malondialdhyde (MDA) in kidney tissue homogenates. The administration of L-arginine (70 mg/kg/d p.o in drinking water 5 d before and 5 d after the CDDP injection) significantly ameliorated the renotoxic effects of CDDP, as judged by restoring the normal responses of isolated bladder rings to Ach, and also by an improvement in a range of renal function indices, which included serum urea and creatinine concentrations and kidney weight. In addition, L-arginine prevents the rise of MDA, as well as a reduction of GSH-Px and catalase activities in kidney tissues homogenates. On the other hand, the administration of L-NAME (4 mg/kg/d p.o) resulted in no protection against renal dysfunction that was induced by CDDP treatment. The findings of this study suggest that L-arginine can attenuate kidney injury that is produced by CDDP treatment. In addition, L-arginine may be a beneficial remedy for CDDP-induced renal toxicity, and could be used to improve the therapeutic index of CDDP.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.137-145
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• 2004

Intensive animal industries create large volumes of nutrient rich effluent which, if untreated, has the potential for substantial environmental degradationand to recover valuable nutrients that would otherwise be lost. Members of the family Lemnaceae are widely used in lagoon systems, to achieve inexpensive and efficient remediation of effluent. Only limited research has been conducted into their growth in highly eutrophic media and there has been little done to systematically distinguish between different types of media. This study examined the growth characteristics of duckweed in abattoir effluent and explored possible ways of ameliorating the inhibitory factors to growth on this medium. A series of pot trials was conducted to test the tolerance of duckweed to abattoir effluent partially remediated by a sojourn in anaerobic fermentation ponds, both in its unmodified form and after the addition of acid to manipulate pH, and the addition of bentonite. Unmodified abattoir effluent was highly toxic to duckweed, even at dilutions of 3:1. Duckweed remained viable and grew sub-optimally in simplified media with total ammonia nitrogen (TAN) concentrations of up to 100 mg/L. Duckweed grew vigorously in effluent diluted 1:4 v/v, containing 56 mg TAN/L when modified by addition of acid (to decrease pH to 7) and bentonite at 0.5%. The results of this study suggest that bentonite plays an important role in modifying the toxicity of abattoir effluent to duckweed.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.547-559
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• 2007

Bacillus thuringiensis (Bt) was first described by Berliner [10] when he isolated a Bacillus species from the Mediterranean flour moth, Anagasta kuehniella, and named it after the province Thuringia in Germany where the infected moth was found. Although this was the first description under the name B. thuringiensis, it was not the first isolation. In 1901, a Japanese biologist, Ishiwata Shigetane, discovered a previously undescribed bacterium as the causative agent of a disease afflicting silkworms. Bt was originally considered a risk for silkworm rearing but it has become the heart of microbial insect control. The earliest commercial production began in France in 1938, under the name Sporeine [72]. A resurgence of interest in Bt has been attributed to Edward Steinhaus [105], who obtained a culture in 1942 and attracted attention to the potential of Bt through his subsequent studies. In 1956, T. Angus [3] demonstrated that the crystalline protein inclusions formed in the course of sporulation were responsible for the insecticidal action of Bt. By the early 1980's, Gonzalez et al. [48] revealed that the genes coding for crystal proteins were localized on transmissible plasmids, using a plasmid curing technique, and Schnepf and Whiteley [103] first cloned and characterized the genes coding for crystal proteins that had toxicity to larvae of the tobacco hornworm, from plasmid DNA of Bt subsp. kurstaki HD-1. This first cloning was followed quickly by the cloning of many other cry genes and eventually led to the development of Bt transgenic plants. In the 1980s, several scientists successively demonstrated that plants can be genetically engineered, and finally, Bt cotton reached the market in 1996 [104].

• Development and Reproduction
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• v.15 no.1
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• pp.17-24
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• 2011

Lipid metabolites involved in cellular regulation as signaling mediators. Prostaglandins (PGs), metabolites of lipid are involved to pregnancy at the time of implantation but the functional roles of PGs on embryo development are still controversy and largely unknown. In previous report, the levels of $PGE_2$ and $PGF_{2a}$ at embryos of morula stage and blastocyst stage were explored (Cheon et al., 1998). In this study, the previous suggestion was confirmed and the possible downstream mediator of prostaglandin $E_2$ and prostaglandin $F_{2a}$ on the expansion and hatching of mouse embryo was examined. As expected, developmental rate of the blastocyst to expanded stage was a concentration-response curve that showed the highest expansion rate at 10 ${\mu}M$ $PGE_2$, but at 100 ${\mu}M$ $PGE_2$, the rate was decreased. In contrast to the $PGE_2$, $PGF_{2a}$ stimulated expansion without toxicity at highest concentration. Cotreatment of PGs with indomethacin overcame the inhibitory effects of indomethacin in expansion. Exogenous PGs also improved the development of expanded embryos to the hatching stage. Besides, PGs receptors' transcripts detected at blastocyst. $PGE_2$ was caused of calcium fluctuation in the blastocyst but $PGF_{2a}$ did not. The changes of intracellular calcium concentration were different between indomethacin pretreated embryos and non-treated embryos. Based on these results it is suggested that PGs work as paracrine and/or autocrine factors through calcium and the others which were not identified in this study.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.10a
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• pp.70-86
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• 2003

Despite its usability, TCE has been managed as a hazardous material due to the toxicity and many contamination cases were surveyed in some developed countries. U.S.EPA(Kram et al., 2001) suggested DNAPL characterization methods and approaches based on survey experiences at several sites. However, Korea has not the least assessment of contamination and trial of remediation, although there are a lot of doubtable areas where ground water would be contaminated with TCE. In this study, we try to assess the volume and extent of ground water contamination with TCE and delineate the contamination source zones in an industrial area. Ground water in this area flows through fractures and the contaminant TCE has the properties of high volatility, high density and low partitioning to soil material. Thus, we applied a variety of technical approaches to identify the contamination status; documentary, hydrogeochemical, hydrogeological and geological surveys. In addition, additional survey was performed based on the interim findings, which showed that ground water contamination was limited to the relatively small area with high concentrations to the deep place. The contamination source zone is estimated to be the asphalt test institute where a great deal of TCE has been used to analyze the amount of asphalt soluble in TCE since 1984. Based on the contamination characterization and a myriad of documents about ground water remediation, appropriate site remediation management options will be recommended later. This study is now under way and this paper was focused on describing the technical approaches used to achieve the goals of this study.

• Journal of Plant Biology
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• v.37 no.3
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• pp.309-316
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• 1994

To make regional comparisons of water status of pitch pine, the temporal changes of water status in pitch pine were investigated at different areas; urban Seoul (heavily polluted area), surburb of Seoul (lightly polluted area), and rural area (control). The effects of air pollutants, acid rain and chemical properties of soil on water deficit in pitch pine were also investiaged. Water content of needles growing at polluted areas were usually lower than that at unpolluted area. Water saturation deficit of needles growing at polluted areas were usually higher than that at unpolluted area especially in dry season. These results indicated that water in needles growing at polluted areas were usually more deficient than that at unpolluted area, and were more deficient in April than other months. At polluted areas, the older the needles were, the more quickly transpirated the water in the needle was. At unpolluted areas, however, water in old needles was not so quickly transpirated as those at polluted areas. Water potential of needles of pitch pine seedlings treated with simulated acid rain (SAR) of pH 3.5 decreased more quickly than that of needles treated with SAR of pH 5.6. Loss of water through epicuticular layer was greater in the following order: magnesium deficiency＋100 $\mu$M aluminium>100$\mu$M aluminium>magnesium deficiency>control. In addition to Mg deficiency and Al toxicity, growth decline of pitch pine widely occurring in polluated Seoul could to a large extent be due to cuticle degredation and abnormal vertical distribution of fine roots, which lead to water stress, particularly in dry seasons.

• IMMUNE NETWORK
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• v.2 no.1
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• pp.49-52
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• 2002

Background: The possibility that G-CSF recruits leukemic cells from the G0 to S phase, which may lead to a greater susceptibility to cytotoxic drugs, such as ara-C, has been presented in Harada's study. Methods: In this study, we referred to the protocol of Harada et al 1 to try G-CSF combined marrow-ablative chemotherapy and autologous PBSCT, for the treatment of AML patients in CR1 status. Between January 1997 and March 1998, six AML patients (3: children, 3: adults) in CR1 status were autografted and followed up to 3 years. Results: The major regimen related toxicity was composed of mucositis and diarrhea without death. The time of ANC recovery to 500/L and 1,000/L was 11~48 and 16~81 days, respectively. The mean time of platelet recovery to 20,000/L and 50,000/L was 21~233 and 35~370 days, respectively. The platelet recovery time to 50,000/L was markedly prolonged for more than 100 days in four patients (66.7%). Moreover, four patients (66.7%) experienced a relapse of leukemia after transplantation, with a mean interval of 147.5 days after PBSCT. Two patients were in CR status for 53 and 51 months after PBSCT, respectively. Conclusion: The G-CSF combined marrow-ablative chemotherapy and autologous PBSCT resulted in a markedly delayed platelet recovery and no advantages for decreasing the relapse rate of AML. But, further studies will be warranted.

• Journal of Periodontal and Implant Science
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• v.50 no.6
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• pp.392-405
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• 2020

Purpose: Titanium implants are widely used in the treatment of dentition defects; however, due to problems such as osseointegration failure, peri-implant bone resorption, and periimplant inflammation, their application is subject to certain restrictions. The surface modification of titanium implants can improve the implant success rate and meet the needs of clinical applications. The goal of this study was to evaluate the effect of the use of porous titanium with a chitosan/hydroxyapatite coating on osseointegration. Methods: Titanium implants with a dense core and a porous outer structure were prepared using a computer-aided design model and selective laser sintering technology, with a fabricated chitosan/hydroxyapatite composite coating on their surfaces. In vivo and in vitro experiments were used to assess osteogenesis. Results: The quasi-elastic gradient and compressive strength of porous titanium implants were observed to decrease as the porosity increased. The in vitro experiments demonstrated that, the porous titanium implants had no biological toxicity; additionally, the porous structure was shown to be superior to dense titanium with regard to facilitating the adhesion and proliferation of osteoblast-like MC3T3-E1 cells. The in vivo experimental results also showed that the porous structure was beneficial, as bone tissue could grow into the pores, thereby exhibiting good osseointegration. Conclusions: Porous titanium with a chitosan/hydroxyapatite coating promoted MC3T3-E1 cell proliferation and differentiation, and also improved osseointegration in vitro. This study has meaningful implications for research into ways of improving the surface structures of implants and promoting implant osseointegration.

• Advances in environmental research
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• v.10 no.1
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• pp.59-86
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• 2021

Landfilling is the most commonly adopted method for a large quantity of waste disposal. But, the main concern related to landfills is the generation of leachate. The leachate is high strength wastewater that is usually characterized by the presence of high molecular recalcitrant organics. Several conventional methods are adopted for leachate treatment. However, these methods are only suitable for young leachate, having high biodegradability and low toxicity levels. The mature and stabilized leachate needs advanced technologies for its effective treatment. Advanced oxidation processes (AOPs) are very suitable for such complex wastewater treatment as reported in the literature. After going through the literature survey, it can be concluded that Fenton-based approaches are effective for the treatment of various high/low strength wastewaters treatment. The applications of the Fenton-based approaches are widely adopted and well recognized due to their simplicity, cost-effectiveness, and reliability for the reduction of high chemical oxygen demand (COD) as reported in several studies. Besides, the process is relatively economical due to fewer chemical, non-sophisticated instruments, and low energy requirements. In this review, the conventional and advanced Fenton's approaches are explained with their detailed reaction mechanisms and applications for landfill leachate treatment. The effect of influencing factors like pH, the dosage of chemicals, nature of reaction matrix, and reagent ratio on the treatment efficiencies are also emphasized. Furthermore, the discussion regarding the reduction of chemical oxygen demand (COD) and color, increase in biodegradability, removal of humic acids from leachate, combined processes, and the pre/post-treatment options are highlighted. The scope of future studies is summarized to attain sustainable solutions for restrictions associated with these methods for effective leachate treatment.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.159-159
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• 2022

Nitric oxide (NO) is a versatile signaling molecule, which is not only involved in plant growth and development but also regulates biological processes in response to biotic and abiotic stresses. Exogenous application of NO regulates the endogenous level of nitric oxide in response to stress conditions and therefore, NO donors are frequently used for stress alleviation. However, NO has very short half-life along with high reactivity. Therefore, conventional NO donors are often disadvantageous due to the relative instability of NO. On the contrary, development of NO releasing nanoparticles is a potential technique for enhancing the availability of NO in plants. Therefore, our aim was to synthesize such potential NO releasing nanoparticles which may be useful for application in agriculture. We have prepared Chitosan encapsulated S-nitrosoglutathione nanoparticles (GSNONP) and tried it with different concentrations for basic research in Arabidopsis thaliana. Our results suggest that lower concentration of this nanoparticle is highly effective for better growth of plants whereas higher concentration produces toxicity that leads to plant death. We observed better growth of Arabidopsis thaliana at 1µM concentration of the GSNONP compared to free GSNO.