• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.427-438
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• 2023

Biocide dichlofluanid breaks down quickly and accumulates easily in sediment, potentially causing a persistent impact on various marine organisms. We analyzed the potential toxicity of dichlofluanid on major aquaculture species in Korea, Undaria pinnatifida. Female gametophytes of U. pinnatifida were exposed to dichlofluanid at concentrations of 0, 1, 2, 4, 8, 16, and 32 mg L^-1, and their survival and relative growth rate were analyzed. The no observed effect concentration(NOEC), lowest observed effect concentration (LOEC), and median lethal concentration (LC₅₀) for female gametophyte survival were determined as 1, 2, and 10.82 (95% CI: 8.87-13.23) mg L^-1, respectively. The NOEC, LOEC, and median effective concentration (EC₅₀) for relative growth rate were 1, 2, and 6.58 (95% CI: 6.03-7.17) mg L^-1, respectively. Female gametophytes of U. pinnatifida were expected to experience toxic effects at concentrations above 2 mg L^-1 of dichlofluanid. These research findings are expected to serve as important reference data for evaluating the toxicity effects of U. pinnatifida in its early life stages when exposed to dichlofluanid.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.2
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• pp.126-135
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• 2013

This study was performed to have an effect on control the growth of algae such as "Actinastrum fluviatile" which occurs frequently in the aquaculture tank using by a cold plasma, and it also would be expected to promote the growth of water plants due to active element causing OH radicals in the water. In addition, it was verified on the death rate as 99.9% on the scale protrusion of "Aeromonas hydrophila" as well as E. coli, especially, under extreme conditions more than 100 million pathogenic bacterium in the aqua pet tank, the ornamental fish had to act in a safe and healthy environment at over 98% death rate within 48 hours. It has been proven to give no affect on aerobic bacteria that exist in the filter or soil because there was no residual toxicity in the water tank. As the results, it will help to develop and apply on the sterilization device in other industries as well as aquarium organisms due to adopted energy-saving algorithm and reliability in use.

• Journal of Korean Neurosurgical Society
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• v.57 no.5
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• pp.315-322
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• 2015

Intracranial germ cell tumors (ICGCT) occur in 2-11% of children with brain tumors between 0-19 years of age. For treatment of germinoma, relatively low radiation doses with or without chemotherapy show excellent 10 year survival rate of 80-100%. Past studies showed that neoadjuvant chemotherapy combined with focal radiotherapy resulted in unacceptably high rates of periventricular tumor recurrence. The use of generous radiation volume which covers the whole ventricular space with later boost treatment to primary site is considered as standard treatment of intracranial germinomas. For non-germinomatous germ cell tumors (NGGCT), 10-year overall survival rate is still much inferior than that of intracranial germinoma despite intensive chemotherapy and high-dose radiotherapy. Craniospinal radiotherapy combined with cisplatin-based chemotherapy provides the best treatment outcome for NGGCT; 60-70% of overall survival rate. There is a debate on the surgical role whether surgery can contribute to improved treatment outcome of NGGCT when added to combined chemoradiotherapy. Because higher dose of radiotherapy is required for treatment of NGGCT than for germinoma, it is tested whether whole ventricular irradiation can replace craniospinal irradiation in intermediate risk group of NGGCT to minimize radiation-related late toxicity in the recent studies. To minimize the treatment-related neural deficit and late sequelae while maintaining long-term survival rate of ICGCT patients, optimized administration of chemotherapy and radiotherapy should be selected. Use of technically upgraded radiotherapy modalities such as intensity-modulated radiotherapy or proton beam therapy is expected to bring an improved neurocognitive outcome with longitudinal assessment of the patients.

• 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.

• Korean Journal of Environmental Agriculture
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• v.24 no.1
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• pp.12-16
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• 2005

As a silicate source to rice, a coal ash was selected and mixed with phosphor-gypsum (50:50, wt $wt^{-1}$) to reduce the potential of boron toxicity and to supply calcium element. We expected that high con tent of calcium in this mixture might convert water-soluble phosphorus to less soluble forms and then reduce the release of soil phosphorus to surface runoff. The mixture was applied with the rate of 0, 20, 40, and 60 Mg $ha^{-1}$ in paddy soil (Nagdong series, a somewhat excessively drained loamy fine sand) in Daegok, Jinju, Korea The mixture reduced significantly water-soluble phosphorus (W-P) in the surface soils by shifting from W-P and Fe-P to Ca-P and Al-P during whole rice cultivation. In contrast with W-P, plant available phosphorus increased significantly with the mixture application due to high content of phosphorus and silicate in the mixture. The mixture of coal ash and phosphor-gypsum (50:50, wt $wt^{-l}$) would be a good alternative to reduce a phosphorus export in rice paddy soil together with increasing rice yields.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.71-74
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• 2011

As control of swine consumptive disease is the key of success in pig farming business, the effect of Oldenlandidae Herba on prevention of swine diseases as an alternative medicine was investigated in-vivo. As it contains substances such as ${\beta}$-sitisterol, ursolic acid and 3-O-${\beta}$-D-giucoside, it is effective on suppression of colonic tumor in rats and also, is widely used as an preventative medicine of cancer and inflammation in Chinese medicine. In this experiment, sows and piglets on two different farms were treated with Oldenlandidae Herba, and they recoded weaning rate greater than 80%, which were higher than national average 70% (PSY 68%). Meanwhile, neither organ accumulation nor toxicity has been detected on the basis of hematology and serum chemistry. In conclusion, the extracts of Oldenlandidae Herba is expected to be an good alternative medicines for swine productivity.

• Journal of Marine Life Science
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• v.7 no.2
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• pp.86-93
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• 2022

The ecotoxicity test method using Undaria pinnatifida spore is challenging to use throughout the year. Since U. pinnatifida female gametophytes can be cultured in the laboratory, they can be used for ecotoxicity testing at any time. Changes in female gametophyte survival rate and relative growth rate in U. pinnatifida exposed to various environmental conditions were analyzed. The female gametophyte of U. pinnatifida was exposed to salinity (5~40 psu), temperature (5~30℃), pH (4~10), and light intensity (0~120 μmol photon m^-2 s^-1). Based on the highest average value, the survival rate of female gametophyte was highest at a temperature of 20℃, salinity 27.5 psu, pH 8, and light intensity 30 μmol photon m^-2 s^-1. And the relative growth rate was highest at a temperature of 15℃, salinity 35 psu, pH 9, and light intensity of 60 μmol photon m^-2 s^-1. As a result of this study, the method using the optimal conditions for the survival rate and relative growth rate is expected to be a practical test method that can complement the current method.

• Journal of Pharmaceutical Investigation
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• v.41 no.4
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• pp.239-247
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• 2011

Simvastatin is an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, which catalyzes the conversion of HMG-CoA to mevalonate, an early and rate-limiting step in the biosynthesis of cholesterol. Simvastatin has good permeability, but it also has low solubility (BCS class II), which reduces its bioavailability. To overcome this problem, a solid dispersion is formed using a spray-dryer with polymeric material carrier to potentially enhance the dissolution rate and extend drug absorption. As carriers for solid dispersion, Gelucire$^{(R)}$44/14 and Gelucire$^{(R)}$ 50/13 are semisolid excipients that greatly improve the bioavailability of poorly-soluble drugs. To avoid any toxic effects of an organic solvent, we used aqueous medium to melt Tween$^{(R)}$ 80 and distilled water. The structural behaviors of the raw materials and the solid dispersion were analyzed by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The DSC and PXRD data indicated that the crystalline structure of simvastatin was transformed to an amorphous structure through solid dispersion. Then, solid dispersion-based tablets containing 20 mg simvastatin were prepared with excipients. Dissolution tests were performed in distilled water and artificial intestinal fluid using the USP paddle II method. Compared with that of the commercial tablet (Zocor$^{(R)}$ 20 mg), the release of simvastatin from solid dispersion based-tablet was more efficient. Although the stability study is not complete, this solid dispersion system is expected to deliver poorly water-soluble drugs with enhanced bioavailability and less toxicity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.205-210
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• 2006

The widespread use and distribution of chloroethylene organic compounds is of serious concern owing to their carcinogenicity and toxicity to humans and wildlife. In an effort to develop active bacterial consortia that could be useful for bioremediation of chloroethylene-contaminated sites in Africa, 16 combinations of 5 dichloroethylene (DCE)-utilizing bacteria, isolated from South Africa and Nigeria, were assessed for their ability to degrade cis- and trans- DCEs as the sole carbon source. Three combinations of these isolates were able to remove up to 72% of the compounds within 7 days. Specific growth rate constants of the bacterial consortia ranged between 0.465 and $0.716\;d^{-1}$ while the degradation rate constants ranged between 0.184 and $0.205\;d^{-1}$ with $86.36{\sim}93.53\;and\;87.47{\sim}97.12%$ of the stoichiometric-expected chloride released during growth of the bacterial consortia in cis- and trans-DCE, respectively. Succession studies of the individual isolates present in the consortium revealed that the biodegradation process was initially dominated by Achromobacter xylosoxidans and subsequently by Acinetobacter sp. and Bacillus sp., respectively. The results of this study suggest that consortia of bacteria are more efficient than monocultures in the aerobic biodegradation of DCEs, degrading the compounds to levels that are up to 60% below the maximum allowable limits in drinking water.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.799-805
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• 2016

Background: There is no standard treatment for patients with platinum-resistant or refractory epithelial ovarian cancer. Single agent chemotherapies have evidence of more efficacy and less toxicity than combination therapy. Most are very expensive, with appreciable toxicity and minimal survival. Since it is difficult to make comparison between outcomes, economic analysis of single-agent chemotherapy regimens and best supportive care may help to make decisions about an appropriate management for the affected patients. Objective: To evaluate the cost effectiveness of second-line chemotherapy compared with best supportive care for patients with platinum-resistant or refractory epithelial ovarian cancer. Materials and Methods: A Markov model was used to estimate the effectiveness and total costs associated with treatments. The hypothetical patient population comprised women aged 55 with platinum-resistant or refractory epithelial ovarian cancer. Four types of alternative treatment options were evaluated: 1) gemcitabine followed by BSC; 2) pegylated liposomal doxorubicin (PLD) followed by BSC; 3) gemcitabine followed by topotecan; and 4) PLD followed by topotecan. Baseline comparator of alternative treatments was BSC. Time horizon of the analysis was 2 years. Health care provider perspective and 3% discount rate were used to determine the costs of medical treatment in this study. Quality-adjusted life-years (QALY) were used to measure the treatment effectiveness. Treatment effectiveness data were derived from the literature. Costs were calculated from unit cost treatment of epithelial ovarian cancer patients at various stages of disease in King Chulalongkorn Memorial Hospital (KCMH) in the year 2011. Parameter uncertainty was tested in probabilistic sensitivity analysis by using Monte Carlo simulation. One-way sensitivity analysis was used to explore each variable's impact on the uncertainty of the results. Results: Approximated life expectancy of best supportive care was 0.182 years and its total cost was 26,862 Baht. All four alternative treatments increased life expectancy. Life expectancy of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 0.510, 0.513, 0.566, and 0.570 years, respectively. The total cost of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 113,000, 124,302, 139,788 and 151,135 Baht, respectively. PLD followed by topotecan had the highest expected quality-adjusted life-years but was the most expensive of all the above strategies. The incremental cost-effectiveness ratios (ICER) of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 344,643, 385,322, 385,856, and 420,299 Baht, respectively. Conclusions: All of the second-line chemotherapy strategies showed certain benefits due to an increased life-year gained compared with best supportive care. Moreover, gemcitabine as second-line chemotherapy followed by best supportive care in progressive disease case was likely to be more effective strategy with less cost from health care provider perspective. Gemcitabine was the most cost-effective treatment among all four alternative treatments. ICER is only an economic factor. Treatment decisions should be based on the patient benefit.