• Analytical Science and Technology
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• v.29 no.2
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• pp.94-103
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• 2016

An analytical method was developed to determine the amount of spinetoram (spinetoram J and spinetoram L) in livestock samples. The spinetoram was extracted with acetonitrile and purified through a primary secondary amine (PSA) sorbent. The spinetoram residues were then quantified and confirmed using a liquid chromatography–tandem mass spectrometer (LC-MS/MS) in the positive ion mode using multiple reactions monitoring (MRM). Matrix-matched calibration curves were linear over the calibration ranges (0.005-0.5 mg/kg) into a blank extract with r² > 0.994. The limits of detection and quantification were 0.002 and 0.01 mg/kg, respectively. The recovery results of spinetram ranged between 81.9-106.4% at different concentration levels (LOQ, 10LOQ, 50LOQ, n=5) with relative standard deviations (RSDs) less than 10%. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL40, 2003). An interlaboratory study was conducted to validate the method. The proposed analytical method proved to be accurate, effective, and sensitive for spinetoram determination. The method will be used as an official analytical method in Korea.

• Tuberculosis and Respiratory Diseases
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• v.55 no.1
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• pp.88-97
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• 2003

Background : Although smoking is a major cause of chronic obstructive pulmonary disease (COPD), only 10-20% of cigarette smokers develop symptomatic COPD, which suggests the presence of genetic susceptibility. This genetic susceptibility to COPD might depend on variations in the activities of the enzyme that detoxify hazardous chemical products, such as microsomal epoxide hydrolase (mEPHX) and glutathione-S transferase M1 subunit (GSTM1) genes. Methods : The genotypes of 58 patients with COPD, and 79 age matched control subjects, were determined by a polymerase chain reaction, followed by restriction fragment length polymorphism (PCR-RFLP) for the mEPHX, and multiplex PCR for the GSTM1. Results : GSTM1 was deleted in 53.3% of the subjects. There was no difference in GSTM1 deletion rates between the COPD patients (32/58, 55.2%) and the control subjects (41/79, 51.9%). The combination patterns of two polymorphisms of mEPHX showed slow enzyme activity in 29(21.2%), normal in 73(53.3%) and fast in 32(23.4%). The COPD group (7/57, 12.3%) showed a significantly lower incidence of slow enzyme activity compared to the control subjects (22/77, 28.6%, p<0.05). However, when the COPD and control groups were compared with smokers only, there were no significant differences in the genotypes of GSTM1 and mEPHX. Conclusion : The genotypes of GSTM1 and mEPHX were not significant risk factors of COPD in this cohort of study.

• Journal of Aquaculture
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• v.4 no.2
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• pp.111-128
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• 1991

In puan area the environmental surveys were carried out at two farms of hard clam, Meretrix lusoria from April 1987 to November 1978 in order to know heather the farm environments could be rehabilitated for the cultivation of hard clam or not. The range of temperature of surface seawater was $10.7{\~}27.4^{\circ}C$, pH $7.6{\~}8.2$, salinity $22.3{\~}30.3$ ppt, COD $0.20{\~}4.71\;mg/{\ell}$, sulfide $0.04{\~}0.22\;{\mu}g-at./{\ell}$, suspended solid $34.8{\~}199.3\;mg/{\ell}$ chlorophyll a $3.71{\~}49.02\;mg/m^3$, TIN $2.01{\~}24.47\;{\mu}g-a5./{\ell}$, phosphate $0.60{\~}11.03\;{\mu}g-at./{\ell}$ and silicate $4.04{\~}476.36\;{\mu}g-at./{\ell}$. The range of temperature of substratum (bottom soil) was $14.2{\~}29.7^{\circ}C$, pH $8.3{\~}9.5$, water content of substratum was $0.28{\~}0.49\;mg/g$ dried mud, COD $2.80{\~}50.94\;mg/g$ dried mud, total organic matter $1.05{\~}1.97\%$ concentration of total Kjedhal nitrogen $31.9{\~}194.9\;{\mu}g./{\ell}$ dried mud, and sulfide $0.032{\~}0.133\;mg/g$ dried mud. Fine sand was dominant ranging over $92{\~}95\%$ and silt and clay was $2.8{\~}8.1\%$ of the composition of substratum. Some residual agricultural chemicals, ${\alpha},\;{\beta},\;{\gamma}$-BHC, heptachlor, heptachlor-epoxide, aldrin, DDE, DDT and dieldrin were detected in hard clams collected from Puan areas. Especialy, more chemical were detected during the period of rainfalls. From above results, it is considered that the hard clam frams were not yet recovered from deteriorated conditions for aquaculture.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.168-173
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• 2015

This study estimated the degree of uterine inflammation and resumption of ovarian cyclicity in postpartum dairy cows. In addition, the prevalence of health problems during calving and the postpartum period was investigated. A total of 224 Holstein dairy cows from four dairy farms in Chungcheong Province were used for the study. Uterine discharge was scored on a 0 to 5 rank scale (metricheck score) using a metricheck instrument from 1 to 8 weeks postpartum and uterine cytology (neutrophil level) was examined at 4, 6 and 8 weeks postpartum to evaluate uterine inflammation. Resumption of ovarian cyclicity was evaluated based on progesterone analysis (${\geq}1ng/mL$) at 4, 6 and 8 weeks postpartum. Postpartum disorders were diagnosed by veterinarians in the research team. The metricheck score decreased linearly (p < 0.0001) from weeks 1 ($3.4{\pm}0.1$) to 4 ($2.0{\pm}0.1$) postpartum, and then remained at that level through week 8 postpartum ($1.6{\pm}0.1$, p > 0.05). The neutrophil levels determined by uterine cytology assays also decreased (p < 0.0001) from week 4 ($22.3{\pm}1.8%$) to 6 ($12.1{\pm}1.4%$) postpartum, and then remained at that level through week 8 postpartum ($9.2{\pm}1.4%$, p > 0.05). The proportion of cows exhibiting the ovarian cyclicity increased linearly (p < 0.0001) from weeks 2 (12.1%) to 8 (74.3%) postpartum. The prevalence of dystocia and retained placenta were 20.5% and 30.4%, respectively. The prevalence of ketosis, milk fever, abomasal displacement, septicemic metritis, endometritis, subclinical endometritis, pyometra, and ovarian cysts were 18.8%, 3.6%, 4.0%, 36.2%, 29.5%, 17.0%, 4.5%, and 14.7%, respectively. The prevalence of digestive problems and mastitis were 5.4% and 9.6%, respectively. The prevalence of culling and death were 4.0% and 3.6%, respectively. The prevalence of dystocia, retained placenta, septicemic metritis, endometritis, ovarian cysts, digestive problems, mastitis, and culling differed among farms (p < 0.05 to 0.01). In conclusion, proper examinations for uterine inflammation and ovarian cyclicity during 4 to 8 weeks postpartum are useful clinical tools to maintain herd reproductive health. Dystocia, retained placenta, septicemic metritis, and endometritis were predominant disorders in dairy cows of the survey area.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.477-487
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• 2019

Objectives: Firefighters are known to be exposed to a variety of toxic substances, but little information is available on the exposure profile of firefighting activities. The aims of this study were to conduct exposure monitoring of toxic chemicals at fire scenes, to compare the concentrations of respective chemicals among firefighting tasks, and to assess the main factors influencing the concentrations of chemicals. Methods: Researchers performed sampling at firefighting scenes during four weeks in 2013. At the scene, we collected samples based on firefighters' own activities and examined the situation and scale of the accident. Collected samples were classified into three categories, including fire extinguishing and overhaul, and were analyzed in the laboratory according to respective analysis methods. Results: A total of fourteen fire activity events were surveyed: five fire extinguishing, six overhaul, and three fire investigations. Although no substance exceeded the ACGIH TLV, PAHs were detected in every sample. Naphthalene ranged from 0.24 to 279.13 mg/㎥ (median 49.6 mg/㎥) and benzo(a)pyrene was detected in one overhaul case at 10.85 ㎍/㎥. Benzene (0.01-12.2 ppm) was detected in every task and exceeded the ACGIH TLV. No significant difference in concentrations between tasks was shown. Conclusions: These results indicate that all firefighting tasks generated various hazardous combustion products, including possible carcinogens.

• Tuberculosis and Respiratory Diseases
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• v.50 no.2
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• pp.158-170
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• 2001

Background : Although an oxidants and antioxidants imbalance has been considered in the pathogenesis of chronic obstructive pulmonary disease (COPD), there is a paucity of reports focussing on the smoking-induced changes of oxidants and antioxidants in COPD. Method : The concentration of antioxidants (ascorbic acid, uric acid, retinol, and $\alpha$- & $\gamma$-tocopherol) was measured in the serum and induced sputum of 30 healthy controls and 34 stable COPD patients using high performance liquid chromatography (HPLC). The inhibition of lipid peroxidation as an index of antioxidant capacity was measured in the serum by a TBA assay. Results : The serum concentration of ascorbic acid, $\alpha$-tocopherol, and retinol were significantly lower in the patients with COPD than in healthy controls ($484.8{\pm}473.3$ vs $1497.8{\pm}819.2\;pmol/L$, $48.38{\pm}17.34$ vs $73.96{\pm}26.29\;pmol/L$, p<0.001, and $9.51{\pm}8.33$ vs $15.01{\pm}5.88\;pmol/L$, p<0.05, respectively, mean$\pm$SD). However, there were little differences in the ascorbic acid and uric acid concentrations in the induced sputum between the COPD patients and the controls. The induced sputum to serum ratio of ascorbic acid was significantly higher in COPD patients compared with healthy control (0.375 vs 0.085, p<0.05). In the normal controls, the serum ascorbic acid concentration was lower in smokers than in nonsmokers ($1073{\pm}536$ vs $1757{\pm}845\;pmol/L$, p<0.05), but the level was still higher than that of the COPD patients (p<0.05). The serum retinol levels were correlated with $FEV_1$ in COPD patients (r=0.58, p<0.05). The products of lipid peroxidation were increased in normal smokers and COPD compared with norma1 nonsmokers ($115.56{\pm}19.93$ vs $120.02{\pm}24.56$ vs $91.87{\pm}20.71\;{\mu}mol/{\mu}mol$ Pi of liposome, p<0.05). Conclusion : Cigarette smoking may induce the dep1etion of serum antioxidants and this depletion of antioxidants is suggested to play a role in the pathogenesis of COPD.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.4
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• pp.497-505
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• 2012

The nutritional, physicochemical and sensory quality characteristics of chilled loins of Jeju Black Cattle, Hanwoo and imported Australian beef were compared. For nutritional properties, moisture and crude protein contents of Jeju Black Cattle beef were 65.91% and 17.39% respectively, the lowest among the comparison groups. On the other hand, their crude fat and crude ash contents were 15.89% and 0.79%, respectively, the highest among the comparison groups. There was a significant difference in crude ash content, but there was no significant difference in the other properties. The Fe and Zn contents of Jeju Black Cattle beef were 29.85 and 48.13 ppm, respectively, lower than those of Hanwoo beef, although the difference was not significant. These values were higher than those of Australian beef (p<0.05). There was no significant difference among the samples in contents of Ca, P, Na and Cu. The total amino acid and essential amino acid contents of Jeju Black Cattle beef were 16.81% and 9.08%, respectively, the lowest among the samples, although the difference was not significant. The ratio of essential amino acids to total amino acids of Jeju Black Cattle beef was 54.01%, the highest among the samples. The saturated fatty acid (43.25%), stearic acid (13.51%), linoleic acid (2.39%) and essential fatty acid (2.47%) contents of Jeju Black Cattle beef were the lowest. However, their unsaturated fatty acid (56.69%), oleic acid (47.80%) and MUFA/SFA ratios were the highest, and there were significant differences compared with Australian beef. There was no significant difference in the PUFA/SFA ratio. Among physicochemical properties, redness ($a^*$) of Jeju Black Cattle beef was the highest while melting point was the lowest (p<0.05). There were no significant differences in lightness ($L^*$), yellowness ($b^*$), pH, water holding capacity, cooking loss or shear force value. For sensory properties, raw meat aroma, cooked meat aroma and palatability of Jeju Black Cattle beef were superior compared to other comparison groups, with significant differences in comparison with Australian beef (p<0.05). However, there were no significant differences in taste, juiciness, or tenderness of cooked meat.

• Journal of Veterinary Clinics
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• v.30 no.3
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• pp.178-185
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• 2013

This study evaluated the effects of milk yield on the postpartum health and reproductive performance of dairy cows. In total, data were collected from 1,060 cows on six dairy farms, including their milk production, body condition score (BCS), postpartum disorders, and reproductive performance. The lactation data were grouped based on the 305-day milk yield into control (< 10,000 kg, n = 445) and high milk yield (${\geq}$ 10,000 kg, n = 615) groups. The milk fat and protein, and BCS were lower during the first 5 months postpartum in the high milk yield group compared with the control group (p < 0.01). Ovarian cysts were more frequent (p < 0.0001) in the high milk yield group (28.6%) than in the control group (15.3%), whereas endometritis tended to be less frequent in the high milk yield group (29.6%) than in the control group (35.1%, p = 0.06). A higher proportion of cows tended to receive reproductive hormones (p = 0.06) in the high milk yield group (62.4%) than in the control group (56.6%). The probability of a pregnancy after first insemination tended to be lower (odds ratio = 0.78, p = 0.07) in the high milk yield group (30.2%) than in the control group (35.2%). Furthermore, the hazard of pregnancy by 210 days in milk was lower in the high milk yield group (hazard ratio = 0.84, p = 0.04) than in the control group, which resulted in a 20-day increase in the median interval to pregnancy. In conclusion, high milk yield was related to lower milk fat and protein, lower BCS, an increased incidence of ovarian cysts, and increased use of reproductive hormones, which resulted in decreased reproductive performance of dairy cows.

• Korean journal of food and cookery science
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• v.29 no.2
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• pp.105-113
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• 2013

Consumer organizations usually lead the opinions of the consumers. This study was performed to investigate the perceptions and information needs of consumer organizations on food additives for the promotion of risk communication. A survey was conducted for 4 weeks in March 2012 by using a self-administered questionnaire consisting of 32 questions. Total 111 responses were collected for analysis. 'Safety (91.0%)' was the most important factor influencing the purchase of processed food, and both 'food additives (24.3%)' and 'environmental pollution (23.4%)' were considered as main risk factors. The longer the career of the members had, the higher negative perceptions on food additives (p<0.01). About 70% of the respondents who had known KFDA's researches on evaluating safety of food additives answered that researches were not enough to make sure the safety. Although lectures and other domestic organization were the main channels for getting information, 'TV' was considered as the most suitable way for it. 'Poor risk communication (32.4%)' was pointed out as the serious problem of government's food safety policy. Based on these results, consumer organizations' low level of trust on government should be overcome by continuous supply of information what they need to facilitate risk communication on food additives.

• Journal of Forest and Environmental Science
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• v.21 no.1
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• pp.83-91
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• 2005

This research was carried out to elucidate the photosnthesis, respiration, and intercellullar $CO_2$ concentration of Kalopanax pictus leaves. The results obtained are summarized as follows; 1. The light compensation points in leaves of Kalopanax pictus seedlings were in the following order; the upper ($34{\mu}mol\;m^{-2}s^{-1}$) middle ($29{\mu}mol\;m^{-2}s^{-1}$) lower leaves ($24{\mu}mol\;m^{-2}s^{-1}$). The light saturated points were at $800{\sim}1200{\mu}mol\;m^{-2}s^{-1}$ in the upper leaves and $400{\mu}mol\;m^{-2}s^{-1}$ in the middle and lower leaves. At the light saturated points, the net photosynthesis rate was in the following order; the upper ($11.1{\mu}mol\;CO_2\;m^{-2}s^{-1}$) middle ($5.15{\mu}mol\;CO_2\;m^{-2}s^{-1}$) lower leaves ($4.01{\mu}mol\;CO_2\;m^{-2}s^{-1}$). The light use efficiency was in the following order; the upper ($0.041{\mu}mol\;CO_2\;{\mu}mol^{-1}$) middle ($0.040{\mu}mol\;CO_2\;{\mu}mol^{-1}$) lower leaves ($0.039{\mu}mol\;CO_2\;{\mu}mol^{-1}$). 2. In the upper leaves of Kalopanax pictus seedlings, the stomatal conductance increased continuously with increasing light intensity. In the middle and lower leaves, it was saturated at $400{\mu}mol\;m^{-2}s^{-1}$. 3. In the upper, middle and lower leaves of Kalopanax pictus seedlings, the intercellular $CO_2$ concentration/the atmospheric $CO_2$ concentration ($C_i/C_a$) ratio rapidly decreased to $600{\mu}mol\;m^{-2}s^{-1}$, and then showed a constant values. 4. In the upper leaves of Kalopanax pictus seedlings, the photorespiration rate was $3.34{\mu}mol\;CO_2\;m^{-2}s^{-1}$ and $CO_2$ compensation point was $48.7{\mu}mol\;mol^{-1}$. Dark respiration rate increased exponentially with increasing leaf temperature, and the photorespiration rate was 2.4 times higher than dark respiration rate.