• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.517-522
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• 2020

Electron beam have many factors that affect dose distribution, so even if identical settings are used, they should be identified and used for radiation treatment, and the effects on the structures in the body are sensitive, making it difficult to investigate uniform dose distribution on tumors. In this study, a dosimeter was produced using PbI₂ which is a photoelectric material, and electrical characteristics were analyzed for 6, 9, and 12 MeV electronics in linear accelerators. The reproducibility test results showed that RSD were 1.1215%, 1.0160%, and 0.05137% respectively at 6, 9, and 12 MeV energies, indicating that the output signals were stable. The linearity evaluation results showed that the R² values of the reliability indicator for straight line trend lines were 0.9999, 0.9999, and 0.9994, respectively, at 6, 9, and 12 MeV, to confirm that the output signal was proportional to PbI₂ as dose increased. The PbI₂ dosimeter in this study is judged to be highly applicable to electromagnet measurement and is thought to be able to be used as a basic study of electron detector through photoelectric material.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.293-298
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• 2017

BACKGROUND: Pyrethroids (PYRs) are a widely used insecticide in agriculture and household area. In mammals, PYRs such as deltamethrin is metabolized to 3-phenoxybenzoic acid (3-PBA) in liver that is mainly excreted in urine. This study is designed to single exposure of deltamethrin to rats in a dose-dependent manner and identify the correlation between deltamethrin exposure and its metabolite (3-PBA) in urine. METHODS AND RESULTS: Exposure levels of deltamethrin were control (0 mg/kg bw), low (0.0705 mg/kg bw), medium (0.705 mg/kg bw) and high (7.05 mg/kg bw) dose. Low concentration was derived by ussing Korea predictive operator exposure model (KoPOEM). Dermal exposure persisted for 6 h, and urine specimens were collected for 24 h. The urine matrix was removed after a series of procedures and 3-PBA was analyzed by gas chromatography/mass spectrometry. CONCLUSION: There was a strong correlation ($R^2=0.83$) between the amount of oral exposure to delta me thrin and urinary levelof3-PBAexcreted. In dermal exposure groups of deltamethrin except high-dose, also there was a good correlation between urinary 3-PBA and deltamethrin exposure, but not stronger than in oral deltamethrin exposure groups. Based on these results, therefore, the amount of 3-PBA in urine can be used as a good monitoring indicator that reflexing the exposure level of deltamethrin to human body.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.2
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• pp.217-226
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• 2016

Objectives : To investigate changes in, and predictors of, metabolic syndrome(MetS) status over a 5-year period in chronic schizophrenic patients and to identify factors associated with the prevention of or recovery from MetS. Methods : In total, 107 patients, all of whom provided written informed consent, were followed from 2011 to 2016 at Naju National Hospital for this study. MetS was defined according to the revised National Cholesterol Education Program-Adult Treatment Panel III guidelines. Results : During follow-up period, 22(20.5%) patients were newly diagnosed to MetS, 14(13.1%) were disappeared, 77(66.4%) were not changed[MetS : 34(31.8%), No MetS 37(34.6%)]. Common significant factors in the two changed groups were triglyceride and waist circumference, not dose and type of antipsychotic medication. Multiple logistic regression analysis revealed that female gender(odds ratio[OR]=2.846, 95% confidence interval[CI] : 1.020-7.942), attending two or more outpatient visits per month(OR=3.155, 95% CI : 1.188-8.379) and taking antidepressant medication(OR=3.991, 95% CI : 1.048-15.205) were significantly associated with MetS after controlling for other confounding variables. Type and dose of antipsychotic medication were not significantly associated with MetS. Conclusions : Triglyceride and waist circumference were important manageable indicator of MetS. Adoption of a healthy lifestyle is more important than adjusting the dose or type of antipsychotic medication in the treatment of chronic schizophrenia patients with MetS.

• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.203-210
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• 2001

Here, we compared the effectiveness of 50 MeV($p{\to}RBe^+$) cyclotron fast neutrons versus $^{60}Co$ ${\gamma}$-rays by the apoptotic fragment frequency in both rat peripheral lymphocytes and crypt cells to check a radiobiological endpoint. The incidence of apoptotic cell death was increased in all irradiated groups, and radiation at all doses trigger rapid changes in both crypt cells and peripheral lymphocytes. These data suggest that apoptosis may play an important role in homeostasis of damaged radiosensitive target organ by removing damaged cells. The curve of dose-effect relationship for these data of apoptotic fragments frequencies was $y=0.3+(6.512{\pm}0.279)D(r^2=0.975)$ after neutrons, while $y=0.3+(4.435{\pm}0.473)D+(-1.300{\pm}0.551)D^2(r^2=0.988)$ after ${\gamma}$-rays. In addition, $y=3.5+(118.410{\pm}10.325)D+(-33.548{\pm}12.023)D^2(r^2=0.992)$ after ${\gamma}$-rays in rat lymphocytes. A significant dose-response relationship was found between the frequency of apoptotic cell and dose. These data show a trend towards increase of the numbers of apoptotic cells with increasing dose. Dose-response curves for high and low linear energy transfer (LET) radiation modalities in these studies were different. The relative biological effectiveness (RBE) value for crypt cells was 1.919. In addition, there were significant peaks on apoptosis induction at 4 and 6h after irradiation, and the morphological findings of the irradiated groups were typical apoptotic fragments in crypt cells that were hardly observed in the control group. Thus, apoptosis induction in both crypt cells and peripheral lymphocytes could be a useful endpoint of rat model for studying screening test and microdosimetic indicator to evaluate the biological effects of radiation-induced cell damage.

• Journal of Veterinary Clinics
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• v.10 no.1
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• pp.111-130
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• 1993

Lead toxicity was evaluated in forty-five cats on a balanced diet, Treated with 0(control), 10, 100(low), 1, 000, 2, 000, and 4, 000(high) ppm of lead acetate orally on a body weight basis. The objectives were to establish toxic dosage level of leaf in cats, to characterize changes in behavior and clinical pathology, and to demonstrate what blood lead concentrations correlate with the known dosages of lead. Some high dose cats showed projectile vomiting, hyperactivity, and seizures. The growth rates did not appear to be altered in any of the dosed groups. Normal blood lead concentration in cats were lower than that of humans, dogs, and cattle. Blood lead concentrations of 3 to 20$\mu\textrm{g}$/100$m\ell$ could be termed a 'subclinical' range in the cat. Clinical lead toxicity in cats may have blood lead concentrations ranging 20 to 120$\mu\textrm{g}$/100$m\ell$. Zinc protoporphyrin concentrations were proportional to lead dosages and a significant ZPP elevation, greater than 50$\mu\textrm{g}$/100$m\ell$, may be indicative of clinical lead toxicity. The enzyme aminolevulinic acid dehydratase showed an inverss dose response relationship for all lead dosages and a significant ZPP elevation, greater than 50$\mu\textrm{g}$/100$m\ell$, may be indicative of clinical lead toxicity. The enzyme aminolevulinic acid dehydratase showed an inverse dose response relationship for all lead dosages and appears to be a good indicator of lead exposure in cats. Urinary aminolevuliruc acid concentrations generally increased with lead dosage, but individual values varied. Hair lead concentrations rose proportionately to lead dosages. Lead at least in high doses appears to inhibit chemotactic activity of polymorphonuclear cells and monocytes. No consistent dose response relationships were observed in hemoglobin, RBC, WBC, neutrophil, lymphocyte, monocyte, and eosinophil counts. There were no consistent dose related changes in total protein, plasma protein, BUN, and ALT values. Reticulocyte counts did not increase significantly in most lead dosage levels, and are probably of little value in diagnosing lead toxicity in cats. The fact that no significant changes were found in nerve conduction velocities may support that there was no segmental demyelination resulting from lead ingestion. The lethal dose in cats appear to range from 60 to 150mg/kg body weight. A reliable diagnosis of lead poisoning can be made utilizing blood lead, ZPP, and ALAD, and hair lead.

• Journal of Radiation Protection and Research
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• v.40 no.3
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• pp.168-173
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• 2015

The present investigation was planned to estimate potential possibility of striped field mice, Apodemus agrarius coreae (A. a. coreae), as a biological dosimeter in radio-environmental ecology. We bred captured wild A. a. coreae at laboratory and classified taxonomically based on external, cranial and tooth characters. Organ weights and splenocytic apoptosis were observed in order to establish a basic data on radiation biology of A. a. coreae (male, 40 weeks old). The biological effects was observed at 24hrs following irradiation (doses : 0, 0.5, 1, 2 Gy, dose rate : $0.8Gymin^{-1}$, $^{137}Cs$). Only thymus weights was significantly decreased. Splenocytic apoptosis was increased after irradiation. But splenocytic apoptosis was decreased in 0.5 Gy ${\gamma}$-irradiated mice compared to those of 0, 1, 2 Gy (P < 0.05). These data suggested that events in thymus and spleen of Korean dark-striped field mice, A. a. coreae THOMAS, could be a potential radio-biological indicator in human environments.

• Journal of Radiation Protection and Research
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• v.18 no.2
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• pp.37-45
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• 1993

Enzyme activity changes in rat blood as biochemical indicator useful for evaluating exposure dose were experimentally studied. The experimental results obtained are as follows: 1) Alkaline phosphatase activities increased in the blood serum until 24 hours after 0.1, 0.25, 0.5, 2 and 4Gy irradiation and its activities returned normal condition after 72 hours of post-irradiation. Creatine kinase activities increased in the blood serum until 72 hours after 2 and 4Gy irradiation but any significant activity changes were not detected after 0.1, 0.25Gy irradiation. 2) Malate dehydrogenase activities did not reveal available changes after 0.1, 0.25, 0.5 Gy irradiation and lactate dehynrogenase activities decreased in the blood serum after 0.1, 0.25, 0.5 Gy irradiation.3) Glutamate oxaloacetate transaminase activity changes were detected in the blood serum after 0.1, 0.25, 0.5, 2, 4Gy(0.1Gy/min.) and GOT activities increased after 0.5, 1, 1.5, 2, 3, 5, 7Gy(0.5Gy/sec.). Any acid phosphatase activities were detected in the blood serum after 0.1, 0.25, 0.5, 2, 4Gy(0.1Gy/min.) and 0.5, 1, 1.5, 2, 3, 5, 7Gy(0.5 Gy/sec.) irradiation. Potentially some of these enzymes can be used as indicator protein for radiation injury. Futher investigation is needed to find better biochemical indicators utilizing recent know-ledge and techniques of biochemistry.

• Journal of the Korea Convergence Society
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• v.9 no.8
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• pp.95-100
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• 2018

The Korea Convergence Society. The aim of this study was to evaluate the association between alcohol consumption and periodontal diseases in Korea adults. The date from the 2014 Korean National Health and Nutrition Survey were used, and 4,328 subjects over 30 years were included in the analysis. Periodontal disease was assessed using the Community Periodontal Index. The adjusted odds ratio of drinking experience, drinking frequency, the drinking amount and the drinking duration were calculated from the logistic regression model with the never-drinkers as a reference group and the logistic model controlled for age, gender, education, and diabetes. This study found that the risk of periodontal disease according to the drinking status of adults over 30 years of age was 1.39 times (95% CI=1.01-1.90) higher than that of non-drinking group when the number of drinks consumed at one time was more than seven glasses. The frequency of binge alcohol consumption, amount of alcohol consumption and duration of alcohol consumption were significantly associated with the risk of periodontal disease in a dose-response pattern among over 30 years. Alcohol consumption was discovered to be a potential risk indicator for periodontitis. Dental practitioners need to be aware that patients who drink may be at higher risk of periodontitis and could benefit from advice to quit drinking and maintain regular dental visits.

• Korean Journal of Acupuncture
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• v.21 no.2
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• pp.47-67
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• 2004

Objectives : In the present study, the effect of Scolopendrid Water-Alcohol Extract (SWAE) applied to acupuncture point BL23 (Shinsu) on the neuropathic pain was examined. A common source of persistent pain in humans is the neuropathic pain. Anti-convulsant drugs are used to treat the neuropathic pain. In the oriental medicine, Scolopendrid was used for long time to treat convulsant syndrome and back pain, etc. Methods : On the bases of the Scolopendrid clinical application, the effect of SWAE applied to the acupuncture point was tested in the rat model of neuropathic pain. Neuropathic pain was induced by tight ligation of L5 spinal nerve. When rats developed pain behaviors, One hundred microliter of SWAE was applied into the ipsilateral BL23 point at a dose of 10 mg/ml under enflurane anesthesia. The foot withdraw latency of the hind limb was measured for an indicator of pain level after each manipulation. Results : SWAE injection increased the mechanical threshold of the foot in the rat model of neuropathic pain significantly for the duration of 4h, suggesting a partial alleviation of pain. SWAE applied to BL23 point produced a significant improvement of mechanical sensitivity of the foot lasting for at least 4h. However, neither contralateral BL23 point, ST25 (Chonchu) point, nor LR3 (Taechung) point produce as much increase of mechanical sensitivity as ipsilateral BL23 point. And, this increase of mechanical sensitivity was dose-dependent. The improvement of mechanical threshold was interpreted as an analgesic effect. In addition, the analgesic effect of Scolopendrid 4 mg/kg injection is equivalent to that of gabapentin 50 mg/kg injection. The relations between SWAE-induced analgesia and endogenous nitric oxide(NO), inducible NO synthase (iNOS)/neuronal NO synthase (nNOS) were also examined. Results were turned out that both NO production and nNOS/iNOS protein expression which are increased by nerve injury were suppressed by SWAE injection applied to BL23 point. Conclusions : The data suggest 1) that SWAE produces a potent analgesic effect on the neuropathic pain model in the rat and 2) that SWAE-induced analgesia modulate endogenous NO through the suppression of nNOS/iNOS protein expression.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.99-105
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• 1986

Optimal balance between control probability and risk of complication is emphasized even in present time, Although certain incidence of intestinal injury is accepted as an inevitable consequence after abdominopelvic irradiation, these complications still remain as problems. 60 mice were irradiated with 250 kVp orthovoltage x-ray machine and $200rad{\times}5/wk$ regimen. Histpathologic findings of colorectum and the relationship with occult blood test were analyzed and possible tolerable dose which would be safe from permanent complication was also estimated. Followings are the results: Mild mucosal and submucosal edema were observed in 1,000 rad irradiated group. Congestion of small vessels was prominent in 2,000 rad irradiated group and infiltration of inflammatory cells was observed in 3,000 rad irradiated group. Denuded mucosa was observed in 3,000 rad irradiated group. Occult blood test is not a proper indicator for rectal denuding or rectal ulcer, but our results suggest the possibility of using this as a relative scale of intestinal damage. Mitotic figures of crypt cells were observed even in 5,000 rad irradiated group, these suggest that the repair capacity of crypt cells are still functioning.