• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• v.3 no.3
• /
• pp.189-196
• /
• 1999

The community structure, phytomass, and primary productivity in Thuja orientalis stands on a limestone area located in Maepo-up, Chungbuk province in Korea were estimated quantitatively. Seven species including a small proportion of Quercus dentata were identified in the tree layer, 26 species including Ulmus macrocarpa in the shrub layer, and 79 species including Carex lnceolata in the herb layer of the Thuja stands. The vertical distribution of the fine root phytomass exhibited a power functional decrease relative to the soil depth. The seasonal changes in the fine root phytomass at a soil depth of 5 cm were closely related to the pecipitation in the study area. The productivity of the stand of stems, branches, leaves, and roots were 10.72, 0.82, 0.45 and 6.46 ton DM. $ha^{-1}$ .$yr^{-1}$, respectively. The Thuja stand had a high foliage(25%) and low rate of production per unit of foliage. The annual turnover rate of the fine roots int he Thuja stand was 6.71 $yr^{-1}$. The net primary production of the overstory including the understory was estimated at 19.48 ton DM.$ha^{-1}$.$yr^{-1}$ including an underground section of 6.46 ton DM.$ha^{-1}$.$yr^{-1}$(33%). The allocation ratio of net production to root was lower in the limestone Thuja communities than at the nearby non-limestone ones, whereas the production efficiency to leaf weight was higher in the limestone communities. These results would seem to indicate that the limited production capacity is due to the calcium toxicity and low availability of iron and phosphorus in a limestone soil with a high pH, calcium, and bicarbonate content with a strategy for survival in a hostile habitat.

• Biomolecules & Therapeutics
• /
• v.22 no.3
• /
• pp.176-183
• /
• 2014

Cognitive impairment is a result of dementia of diverse causes, such as cholinergic dysfunction and Alzheimer's disease (AD). Houttuynia cordata Thunb. (Saururaceae) has long been used as a traditional herbal medicine. It has biological activities including protective effects against amyloid beta ($A{\beta}$) toxicity, via regulation of calcium homeostasis, in rat hippocampal cells. To extend previous reports, we investigated the effects of water extracts of H. cordata herb (HCW) on tauopathies, also involving calcium influx. We then confirmed the effects of HCW in improving memory impairment and neuronal damage in mice with Ab-induced neurotoxicity. We also investigated the effects of HCW against scopolamine-induced cholinergic dysfunction in mice. In primary neuronal cells, HCW inhibited the phosphorylation of tau by regulating p25/p35 expression in $A{\beta}$-induced neurotoxicity. In mice with $A{\beta}$-induced neurotoxicity, HCW improved cognitive impairment, as assessed with behavioral tasks, such as novel object recognition, Y-maze, and passive avoidance tasks. HCW also inhibited the degeneration of neurons in the CA3 region of the hippocampus in Ab-induced neurotoxicity. Moreover, HCW, which had an $IC_{50}$ value of $79.7{\mu}g/ml$ for acetylcholinesterase inhibition, ameliorated scopolamine-induced cognitive impairment significantly in Y-maze and passive avoidance tasks. These results indicate that HCW improved cognitive impairment, due to cholinergic dysfunction, with inhibitory effects against tauopathies and cholinergic antagonists, suggesting that HCW may be an interesting candidate to investigate for the treatment of AD.

• Korean Journal of Microbiology
• /
• v.8 no.1
• /
• pp.41-51
• /
• 1970

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10$^{-4}$ -10$^{-6}$ M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• The Korean Journal of Pesticide Science
• /
• v.7 no.4
• /
• pp.280-287
• /
• 2003

To assess the risk of pesticides on earthworm, the acute toxicities of 10 pesticides were investigated and their toxicity exposure ratios(TERs) were calculated. As the TERs of paraquat dichloride and pendimethalin were more than 100, their risks were rated negligible. Risk of benfuracarb, cadusafos, chlorpyrifos-methyl, endosulfan, isazofos and parathion which have TERs of $10\sim100$ were rated low. However, risk of imidacloprid and phorate which have TER of less than 10 were estimated highly to need a reproduction study. Earthworms were exposed to twenty two pesticides including dazomet 98% GR having PECs of more than $5mg{\cdot}kg^{-1}$ in artificial soil at standard and double dose for 14 days. All the earthworms exposed to dazomet 98% GR and metam-sodium 25% SL were died to show their high risk, while no serious adverse effects were observed in the soil treated with 15 pesticides, calcite 95% WP, calcium polysulfide 36% CF, chlorothalonil 75% WP, daminozide 85% WP, dichlonil 6.7% GR, etridiazole 25% EC, fosetyl-Al 80% WP, glyphosate 41 % SL, hymexazol 30% SL, iprodione 50% WP, machine oil 95% EC, mancozeb 75% WP, propineb 70% WP, terbuthylazine 80% WP and triazophos 40% EC. In case of thiophanate-methyl 70% WP, copper hydroxide 77% WP, dimethoate 46% EC, tolclofos-methyl 50% WP and propamocarb hydrochloride 67% SL, any effect did not show clearly, suggesting an additional subchronic toxicity study. The risk of thiophanate-methyl 70% WP to earthworm was estimated high, considering its subchronic effect, while effects of copper hydroxide 77% WP, dimethoate 46% EC, tolclofos-methyl 50% WP and propamocarb hydrochloride 67% SL to earthworms were negligible, considering no adverse effects in subchronic tests.

• Horticultural Science & Technology
• /
• v.30 no.5
• /
• pp.477-483
• /
• 2012

This study was carried out to investigate the influence of copper concentrations in fertilizer solution on the growth of and nutrient uptake by domestically bred strawberries. The characterization of toxicity symptoms as well as tissue analyses based on dry weight of above ground tissue were also conducted to determine the threshold levels in plants when toxicity developed in copper. The dry weights of the above ground tissue were not significantly different among the treatments of 0.25 mM to 1.0 mM in 'Keumhyang' and 'Maehyang' strawberries and that of 0.25 mM to 3.0 mM in 'Seolhyang' strawberry. This indicates that the 'Seolhyang' strawberry is more tolerant to copper toxicity than 'Keumhyang' or 'Maehyang' strawberries. Application of copper at high concentrations resulted in severe toxicity such as death of extensive areas of leaves. The lower leaves became yellow and die rapidly as the symptoms spread up the plants. The leaf blades and petioles died back to the crown and hang on by mechanical attachment. Symptoms of copper toxicity in lower leaves developed as browning on leaf margins and in patches between leaf veins that became necrotic. The elevation of copper concentrations in fertilizer solution did not influence the tissue phosphorus, potassium, calcium, and magnesium contents based on the dry weight of the above ground tissue. The tissue copper contents increased lineally as the copper concentrations in fertilizer solution were elevated. But the tissue iron, manganese and boron contents were not influenced by the concentrations. When the concentration of copper at which growth of a plant is retarded by 10% is regarded as threshold level, the copper contents based on dry weight of above ground plant tissue should be lower than 71.4, 57.9 and 74.8 $mg{\cdot}kg^{-1}$ in 'Keumhyang', 'Maehyang' and 'Seolhyang' strawberries, respectively. The symptom characterization and established threshold level in copper toxicity would help growers to prevent the reduction of crop growth and yield in 'Seolhyang' strawberry cultivation.

• Korean Journal of Psychosomatic Medicine
• /
• v.19 no.2
• /
• pp.57-65
• /
• 2011

There are numerous drug interactions related to many psychotropic and cardiovascular medications. Firstly, the principles in predicting drug interactions are discussed. Cytochrome P (CYP) 450 plays a significant role in the metabolism of these drugs that are substrates, inhibitors, or inducers of CYP450 enzymes. The two most significant enzymes are CYP2D6 and CYP3A4. The ability of psychotropic drugs to act as inhibitors for the enzymes may lead to altered efficacy or toxicity of co-administered cardiovascular agents as a substrate for the enzymes. The following is also a review of the known interactions between many commonly prescribed cardiovascular agents and psychotropic drugs. Most beta blockers are metabolized by CYP2D6, which may lead to drug toxicity when they use in combination with potent CYP2D6 inhibitors including bupropion, chlorpromazine, haloperidol, selective serotonin reuptake inhibitors, and quinidine. Concomitant administration of lithium with angiotensin converting enzyme inhibitors, angiotensin receptor blockers, and diuretics may increase serum lithium concentrations and toxicity. Calcium channel blockers and cholesterol lowering agents are subject to interactions with potent inhibitors of CYP3A4, such as amiodarone, diltiazem, fluvoxamine, nefazodone, and verapamil. Prescribing antiarrhythmic drugs in conjunction with medications are known to prolong QT interval and/or inhibitors on a relevant CYP450 enzyme is generally not recommended, or needs watchful monitoring. Digoxin and warfarin also have warrant careful monitoring if co-administered with psychotropic drugs.

• Journal of the Korean GEO-environmental Society
• /
• v.12 no.12
• /
• pp.21-30
• /
• 2011

The recycled soil that is proceeded from demolition concrete structures was analyzed by the methods of the physical and mechanical tests of soil and TCLP test to use the soil in low landfilling for the construction of an industrial complex. The laboratory test for diffusion of alkali ion in soil mass was analyzed by the methods of XRF and ICP. The fish toxicity test was also conducted to find an environmental influence. The recycled soil through the laboratory test satisfied the engineering property for low landfilling and the criteria of soil contamination. However, the solution which producted by 1:1 ratio of recycled soil and water contained the high pH concentration by alkali ion. The calcium hydroxide solution by CSH cement paste was estimated as the main reason why pH concentration is increased more than 9.0. The high pH concentration in recycled soils causes a toxicity to the livability of fishes. A diffusion area of pH concentration in the ground was analyzed by the Visual Modflow Ver. 2009 program based on geotechnical investigation. The high pH concentration in the recycled soils can be remained as high value due to cement paste in the long term period. Therefore, in the early stage of landfilling work, the mixing with the weathered granite soil is necessary to control the pH concentration.

• The Korean Journal of Pesticide Science
• /
• v.9 no.3
• /
• pp.243-249
• /
• 2005

The chemical and toxicological studies were conducted with acetamiprid 2% granules including different controlling agents for development of controlled-release acetamiprid 2% granule. The fundamental formulation recipe of acetamiprid 2% granule was prepared by the insoluble matrix using polyethylene wax. Starch, cellulose and mineral (calcium carbonate) were used as controlling agents. As a result of studies, release rate of active ingredient from granules into water static condition at $25^{\circ}C$ was increased by addition of starch and cellulose, but was decreased by addition of calcium carbonate. We could select calcium carbonate as controlling agent and make three granules which there were difference in release profiles of active ingredient according to contents of polyethylene wax. 24 hours-release rates of acetamiprid from three granules into water static condition at $25^{\circ}C$ were respectively 75, 50 and 25% when contents of wax were 2, 10 and 20%. The granule which 24 hours-release rate was 25% showed lower acute toxicity against mice and rats.

• Journal of the Korean Magnetic Resonance Society
• /
• v.19 no.2
• /
• pp.54-60
• /
• 2015

Papiliocin, from the swallowtail butterfly, Papilio xuthus, shows high bacterial cell selectivity against Gram-negative bacteria. Recently, we designed a 22mer analog with N-terminal helix from $Lys^3$ to $Ala^{22}$, PapN. It shows outstanding antimicrobial activity against Gram-negative bacteria with low toxicity against mammalian cells. In this study, we determined the 3-D structure of PapN in 300 mM DPC micelle using NMR spectroscopy and investigated the interactions between PapN and DPC micelles. The results showed that PapN has an amphipathic ${\alpha}$-helical structure from $Lys^3$ to $Lys^{21}$. STD-NMR and DOSY experiment showed that this helix is important in binding to the bacterial cell membrane. Furthermore, we tested antibacterial activities of PapN in the presence of salt for therapeutic application. PapN was calcium- and magnesium-resistant in a physiological condition, especially against Gram-negative bacteria, implying that it can be a potent candidate as peptide antibiotics.

• Fisheries and Aquatic Sciences
• /
• v.6 no.4
• /
• pp.172-179
• /
• 2003

The safety of pufferfish (Lagocephalus gloveri) liver oil and the contents of some nutritional components were examined to obtain important information on their use as high valued functional foods. Pufferfish liver oil was extracted by the hot-water method using $1\%$ NaOH solution to remove toxic compounds, and then purified using a general purifying method of fish oil. Any extraordinary clinical symptoms were not observed from all groups administrated with pufferfish liver oil throughout the test period. None of the rats died when administrated the highest concentration of 10 mL/kg of the pufferfish liver oil. Vitamin A content was 114.2 ppm, as a retinal equivalent in the oil extracted using hot-water, but the content was higher (169.3 ppm) in oil extracted using n-hexane. Vitamin D and E were not detected in ppm in oil extracted using hot-water. Vitamin D in the pufferfish liver oil extracted using n-hexane was also undetected, but vitamin E was at 32.5 ppm. Among the 18 minerals detected, the sodium content was the highest at 253.5 ppm, followed by 13.9 ppm ofpotassium, 1.5 ppm of calcium, 0.2 ppm of magnesium, and other trace minerals. The contents of EPA and DHA were $0.8\%\;and\;14.8\%$, respectively, in the pufferfish liver oil extracted using hot-water. Considering these results, there is potential that pufferfish liver oil could be used as a functional food.