• Korean Journal of Food Science and Technology
• /
• v.30 no.4
• /
• pp.721-727
• /
• 1998

An analytical method for simultaneous and rapid determination of organophosphorus, organochlorine, carbamate, and pyrethroid pesticides in polished rice was developed. The analysis is performed by gas chromatograph with mass selective detector (GC/MSD) in selected ion monitoring (SIM) mode. Pesticides were extracted from samples with acetone by automated Soxhlet apparatus and this extract was evaporated to dryness for the analysis. The residue was dissolved in hexane, followed by a treatment with a Sep-Pak florisil catridge. Pesticides were positively confirmed by GC/MS, retention times, and ion ratios. This analytical method allows a rapid, reliable, and a good recovery of hydrophilic pesticides. Except far captafol, captan, dichlofluanid and dichlorvos, recoveries of 42 pesticides were over 70%.

• Journal of the Korean Society of Radiology
• /
• v.83 no.4
• /
• pp.830-845
• /
• 2022

The male breast is a non-functional and rudimentary organ, but similarly to the female breast, it can be affected by various diseases. In contrast to female breast cancer, male breast cancer has a low incidence, and there is no established breast cancer screening program for male patients. Therefore, the diagnostic evaluation is usually performed in male patients with symptoms such as palpability or pain in the breasts. Furthermore, most adult male patients who visit breast clinics sometimes present with not only breast symptoms but also axillary symptoms, and both the breast and axilla are usually examined during breast ultrasonography in daily clinical practice. The purpose of this pictorial essay was to present the sonographic features of various palpable breast and axillary lesions in adult male patients.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.21 no.1
• /
• pp.69-75
• /
• 2013

This study is a fundamental research to test the applicability of powdered MSWI(Municipal Solid Waste Incinerator) ash melted slag as a seed Crystal for crystallization reaction. Powdered ash melted slag was melted at $1100^{\circ}C$ and ground to lesser than 0.35mm. According to the result of the tests, calcium, enough for crystallization reaction, was eluted from powdered ash melted slag. Moreover, sample(Phosphorus concentration is under 10 mg/L), more than 90% of Phosphorus can be removed. So we rectify the Phosphorus concentration to 100 mg/L. Alkalinity, being well known that it interferes crystallization reaction, effect was studied for synthetic solution(100 mg/L initial Phosphorus concentration, 50 mg/L calcium, pH 8, 1% powdered ash melted slag dosage). For this result, we know that Phosphorus removal is hindered by alkalinity. In addition, the effect of reaction temperature was performed at the same method. The reaction velocity was increased through raising the reaction temperature.

• Korean Journal of Food Science and Technology
• /
• v.53 no.1
• /
• pp.34-39
• /
• 2021

This study investigated the anti-cancer effects of Salicornia herbacea L. fractions in human ovarian cancer cells (OVCAR-3). S. herbacea powder was extracted with 95% EtOH and sequentially fractionated with hexane, dichloromethane (DCM), ethyl acetate, butanol, and H2O. Further, the growth inhibitory effects of the six fractions were determined using the MTS assay. The DCM fraction dramatically decreased cell viability. Similarly, the cell cycle was arrested at the subG1 phase in DCM-treated cells. To confirm apoptosis, the cells were stained with annexin V/FITC-PI solution. Total, early, and late apoptotic cells were significantly increased in the DCM fraction. The mRNA expression of Bcl-2 was reduced, whereas the pro-apoptotic factors Bax and Bak were increased in DCM fraction-treated cells. These results indicated that the DCM fraction in S. herbacea exhibited strong apoptotic effects through the p53-dependent signaling pathway.

• Korean journal of applied entomology
• /
• v.15 no.1 s.26
• /
• pp.1-6
• /
• 1976

his study was conducted to investigate selective toxicity of several organophosphorous and carbamic insecticides against the small brown planthopper (Laodelphax striatellus), the white-backed planthopper (Sogatella furcifera), the brown planthopper (Nilaparvata lugensEugens), and the green rice leafhopper (Nephotetix cincticeps). The test insecticides were the organophosphoric insecticides, Diazinon$(34\%\; Ec.,\; 3\%\; G.),$ $MEP(Sumithion 50\%\; Ec.)$, and PAP(Elsan\; 47.5\%\; Ec.)$ and the carbamic insecticides. MPMC $(Meobal\; 50\%\;WP.)$, $BPMC(Bassa\; 50\%\; Ec.)$, and carbofuran $(Curaterr; 3\%\; G.)$. Toxicitiy for emulsion concentrates and wettable powders were evaluated by dipping method of rice seedlings in the laboratory and that for granulated insecticides evaluated by submerged application with potted plants in the greenhouse. In the test of contact toxicity by seedling dips, Diazinon MEP and PAP showed significantly low toxicity to the brown planthopper and MEP to the green rice leafhopper. In the test of submerged application, Carbofuran showed almost equal toxicity to the four species of the hoppers, but Diazinon was greatly less toxic to the brown planthopper. In general. the organophosphorous insecticides tested seemed to be selective in toxicity to the species of the hoppers, while the carbamic insecticides being less selective. The carbamic insecticides such as MPMC, BPMC and Carbofuran were almost equal in toxicity to the four species of the hoppers tested.

• Journal of Preventive Medicine and Public Health
• /
• v.7 no.1
• /
• pp.115-121
• /
• 1974

In order to evaluate the health hazard due to exposure to organophosphorus insecticides, we measured the blood cholinesterase activity ana urinary para-nitrophenol among 56 exposed subjects. They are orchard workers, rice plant workers and smithion factory workers. The clinical symptoms were also checked by physicians. We also measured the blood cholinesterase activity and urinary para-nitrophenol excretion of 20 urban people and 15 rural people who had never been exposed to organophosphorus insecticides in order to compare them according to age, sex and geographical differences. And these results were also compared with those of exposed groups. The results obtained were as follows. 1. The normal plasma cholinesterase activity and cell cholinestrase activity were $0.861{\pm}0.148\;{\Delta}pH/hr$ and $0.822{\pm}0.154\;{\Delta}pH/hr$. And normal para-nitrophenol in urine was $1.21{\pm}0.52mg/liter$. 2. No significant difference was existed in blood cholinesterase activities and urinary para-nitrophenol excre tion according to sex, age and geographical difference. 3. The plasma cholinesterase activity and cell cholinesterase activity of orchard workers, rice plant workers and smithion factory workers were $0.682{\pm}0.189\;{\Delta}pH/hr,\;0.775{\pm}0.160\;{\Delta}pH/hr,\;0.754{\pm}0.123\;{\Delta}pH/hr,\;and\;0.691{\pm}0.082\;{\Delta}pH/hr,\;0.756{\pm}0.117\;{\Delta}pH/hr,\;0.739{\pm}0.117\;{\Delta}pH/hr$. And significant decreses in blood cholinesterase activities were existed among orchard workers and smithion factory workers compared with control group. 4, The urinary para-nitrophenol excretions of orchard workers, rice plant workers and smithion factory workers were $1.33{\pm}0.66mg/liter,\;1.19{\pm}0.88mg/liter\;and\;1.37{\pm}0.67mg/liter$ and there were no significant difference between exposed groups and control group. 5. The clinical symptoms complained during and after organophosphorus insecticides exposure were frequently ranked by headache (67.7%) and vertigo (64.5%) and muscular ataxia and weakness (51.6%).

• Korean journal of applied entomology
• /
• v.31 no.1
• /
• pp.1-6
• /
• 1992

These studies were carried out to compare toxicological test methods of two spotted spider mite, Tetranychus urticae Koch,; and to investigate relationship between in vivo resistant level of highly acaricide-selected population, and in vitro insensitivity of the AChE in the same population to carbophenothion and ethion. The slide dip method (CV = 8.7%) was of more accuracy and suitability than that of the leaf dip method(CV=12.2%) and leaf disc method (CV= 13.6 %) in determination of the resistant levels of twospotted spider mite to acaricides. The slide dip method also had the advantages of simple treatment with different populations on a slide at the same time, standardization of post-treatement conditions and living plants exclud¬ed from the test. Even though the topical application method(CV =8.1 %) showed high accuracy, it had the demerits of the much time consuming, need of expensive equipment and difficulty of test manipulation. For a limited time, the 22nd successive carbophenothion-selected population of two-spotted spider mite showed 156- and 128-fold resistant levels to carbophenothion and ethion(both alPs), respectively. However, the 24th successive ethion-selected population revealed 64.1- and 65-fold resistant levels to ethion and carbophenothion, respectively. In the inhibition of AChE activity, the carbophenothion-selected population showed 3.3- and 2.7-fold insensitivity in AChE activity to carbophenothion and ethion, respectively. Likewise, the ethion -selected population exhibited 3- and 2.6-fold insensitivity in AChE activity to carbophenothion and ethion, respectively, as compared with that of susceptible population. As a result, a good relation was recognized between in vivo resistance to organophosphorous acaricides and in vitro insensitivity of the AChE to corresponding inhibitors.

• Korean Journal of Environmental Agriculture
• /
• v.10 no.2
• /
• pp.167-177
• /
• 1991

O-ethyl S-methyl ethylphosphonothioate [$LD_{50}$ (rat, oral) 4.6mg/kg ; $K_i$(bovine erythrocyte acetylcholinesterase) 303 $M^{-1\;min-1}$] was selected as a model compound to study the mode of action of O, S-dialkyl alkylphosphonothioates which have been hypothesized to be toxic via a bioactivation process. Two chemical oxidants, meta-chloroperoxybenzoic acid and monoperoxyphthalic acid, and rat liver microsomal oxidases were used to mimic the action of mixed function oxidases on the model compound. The formation of S-oxide, a very unstable active intermediate, was proposed based on the identification of metabolic products.Furthermore, a trapping experiment with ethanol showed that the unstable intermediate S-oxide had the ability to phosphorylate acetylcholinesterase which is an important enzyme in nerve systems. The S-oxide intermediates are presumed to be responsible for the toxicity of O,S-dialkyl alkylphosphonothioates.

• Environmental Analysis Health and Toxicology
• /
• v.20 no.4 s.51
• /
• pp.297-302
• /
• 2005

The purpose of this study was to provide the standard method for the analysis of organophosphorous pesticides such as chlorpyrifos, diazinon, malathion and parathion in blood. We performed method validation for these pesticides in blood according to EURACHEM (A focus For Analytical Chemistry in Europe) guide. For the analysis of the pesticides, we used solid-phase extraction ,column (Waters Oasis $HLB^{(R)}$. After the extraction, the supernatants were evaporated to dryness under the nitrogen stream. They were analyzed by gas chromatography/mass spectrometry (GC/MS) after reconstituting with ethanol. Terbufos was used as an internal standard. To validate this method, we performed verification procedures with the following parameters: selectivity, linearity of calibration, accuracy, precision, limit of detection and quantification. Validation data according to Eurachem guide were adequate for our purpose for the analysis of chlorpyrifos, diazinon, malathion and parathion in blood.

• Korean Journal of Plant Taxonomy
• /
• v.44 no.4
• /
• pp.247-249
• /
• 2014

A newly naturalized plant, Carex scoparia Schkuhr ex Willd. var. scoparia, was found in Mt. Hanseok, Injegun, Gangwon-do, Korea. It belongs to sect. Ovales Kunth and had been known from North America, and was introduced into Europe and New Zealand. This species distinguished from related taxa in Asia, Carex maackii Maxim. and Carex leporina L., by pistillate scales lanceolate and having large perigynia. We propose the new Korean name, 'Han-seok-sa-cho', based on its first collecting place. We also provide descriptions for morphological characters, illustrations, photographs and keys to allied taxa.