• Title/Summary/Keyword: Regulatory Effect

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Photoimmunology -Past, Present and Future-

  • Daynes, Raymond A.;Chung, Hun-Taeg;Roberts, Lee K.
    • The Journal of the Korean Society for Microbiology
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    • v.21 no.3
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    • pp.311-329
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    • 1986
  • The experimental exposure of animals to sources of ultraviolet radiation (UVR) which emit their energy primarily in the UVB region (280-320nm) is known to result in a number of well-described changes in the recipient's immune competence. Two such changes include a depressed capacity to effectively respond immunologically to transplants of syngeneic UVR tumors and a markedly reduced responsiveness to known inducers of delayedtype (DTH) and contact hypersensitivity (CH) reactions. The results of experiments that were designed to elucidate the mechanisms responsible for UVR-induced immunomodulation have implicated: 1) an altered pattern of lymphocyte recirculation, 2) suppressor T cells(Ts), 3) deviations in systemic antigen presenting cell (APC) potential. 4) changes in the production of interleukin-1-like molecules, and 5) the functional inactivation of epidermal Langerhans cells in this process. The exposure of skin to UVR, therefore, causes a number of both local and systemic alterations to the normal host immune system. In spite of this seeming complexity and diversity of responses, our recent studies have established that each of the UVR-mediated changes is probably of equal importance to creating the UVR-induced immunocompromised state. Normal animals were exposed to low dose UVR radiation on their dorsal surfaces under conditions where a $3.0\;cm^2$ area of skin was physically protected from the light energy. Contact sensitization of these animals with DNFB, to either the irradiated or protected back skin, resulted in markedly reduced CH responses. This was observed in spite of a normal responsiveness following the skin sensitization to ventral surfaces of the UVR-exposed animals. Systemic treatment of the low dose UVR recipients with the drug indomethacin (1-3 micrograms/day) during the UVR exposures resulted in a complete reversal of the depressions observed following DNFB sensitization to "protected" dorsal skin while the altered responsiveness found in the group exposed to the skin reactive chemical through directly UVR-exposed sites was maintained. These studies implicate the importance of EC as effective APC in the skin and also suggest that some of the systemic influences caused by UVR exposure involve the production of prostaglandins. This concept was further supported by finding that indomethacin treatment was also capable of totally reversing the systemic depressions in CH responsiveness caused by high dose UVR exposure (30K joules/$m^2$) of mice. Attempts to analyze the cellular mechanisms responsible established that the spleens of all animals which demonstrated altered CH responses, regardless of whether sensitization was through a normal or an irradiated skin site, contained suppressor cells. Interestingly, we also found normal levels of T effector cells in the peripheral lymph nodes of the UVR-exposed mice that were contact sensitized through normal skin. No effector cells were found when skin sensitization took place through irradiated skin sites. In spite of such an apparent paradox, insight into the probable mechanisms responsible for these observations was provided by establishing that UVR exposure of skin results in a striking and dose-dependent blockade of the efferent lymphatic vessels in all peripheral lymph nodes. Therefore, the afferent phases of immune responses can apparently take place normally in UVR exposed animals when antigen is applied to normal skin. The final effector responses, however, appear to be inhibited in the UVR-exposed animals by an apparent block of effector cell mobility. This contrasts with findings in the normal animals. Following contact sensitization, normal animals were also found to simultaneously contain both antigen specific suppressor T cells and lymph node effector cells. However, these normal animals were fully capable of mobilizing their effector cells into the systemic circulation, thereby allowing a localization of these cells to peripheral sites of antigen challenge. Our results suggest that UVR is probably not a significant inducer of suppressor T-cell activity to topically applied antigens. Rather, UVR exposure appears to modify the normal relationship which exists between effector and regulatory immune responses in vivo. It does so by either causing a direct reduction in the skin's APC function, a situation which results in an absence of effector cell generation to antigens applied to UVR-exposed skin sites, inhibiting the capacity of effector cells to gain access to skin sites of antigen challenge or by sequestering the lymphocytes with effector cell potential into the draining peripheral lymph nodes. Each of these situations result in a similar effect on the UVR-exposed host, that being a reduced capacity to elicit a CH response. We hypothesize that altered DTH responses, altered alloresponses, and altered graft-versus-host responses, all of which have been observed in UVR exposed animals, may result from similar mechanisms.

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GATA-3 is a Key Factor for Th1/Th2 Balance Regulation by Myristicin in a Murine Model of Asthma (Myristicin이 Ovalbumin으로 유도한 천식 생쥐모델에서 Th1/Th2 Balance를 조절하는 GATA-3에 미치는 효과)

  • Lee, Kyu;Lee, Chang-Min;Jung, In-Duk;Jeong, Young-Il;Chun, Sung-Hak;Park, Hee-Ju;Choi, Il-Whan;Ahn, Soon-Cheol;Shin, Yong-Kyoo;Lee, Sang-Yull;Yeom, Seok-Ran;Kim, Jong-Suk;Park, Yeong-Min
    • Journal of Life Science
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    • v.17 no.8 s.88
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    • pp.1090-1099
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    • 2007
  • Myristicin, l-allyl-3,4-methylenedioxy-5-methoxybenzene, was one of the major essential oils of nutmeg. However, its anti-allergic effect in the Th1/Th2 immune response was poorly understood. Recently, it was shown that T-bet and GATA-3 was master Th1 and Th2 regulatory transcription factors. In this study, we have attempted to determine whether myristicin regulates Th1/Th2 cytokine production, T-bet and GATA-3 gene expression in ovalbumin (OVA)-induced asthma model mice. Myristicin reduced levels of IL-4, Th2 cytokine production in OVA-sensitized and challenged mice. In the other side, it increased $IFN-{\gamma}$, Th1 cytokine production in myristicin administrated mice. We also examined to ascertain whether myristicin could influence eosinophil peroxidase (EPO) activity. After being sensitized and challenged with ovalbumin (OVA) showed typical asthmatic reactions. These reactions included an increase in the number of eosinophils in bronchoalveolar lavage fluid, an increase in inflammatory cell infiltration into the lung tissue around blood vessels and airways, and the development of airway hyper-responsiveness (AHR). The administration of myristicin before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, these findings provide new insight into the immunopharmacological role of myristicin in terms of its effects in a murine model of asthma.

Modulation of Immune Response by Cimetidine (Cimentidine에 의(依)한 면역반응조절(免疫反應調節))

  • Ha, Tai-You;Lee, Hern-Ku;Song, Yang-Keun
    • The Journal of the Korean Society for Microbiology
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    • v.16 no.1
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    • pp.49-55
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    • 1981
  • Recent studies have demonstrated that histamine could have a modulatory influence on the immune response in vitro and in vivo. However, the effect of histamine on immune response in mice has not been extensivley analyzed. In the present study the regulatory effects of cimetidine, a histamine-2-receptor antagonist(H2 blocker) and histamine on the immune response to sheep red blood cells(SRBC) were evaluated in mice. Mice pretreated with daily intraperitoneal injection of varying concentrations of cimetidine for 14 days were immunized intraperitoneally with various concentrations of SRBC($10^6,\;10^7,\;and\;10^8$ cells) and challenged 4 days post immunization. The cellular immune response was determined by measuring the footpad swelling reaction. Footpad swelling reaction of each mouse was measured at 3hr(Arthus) reaction) and 24 or 48 hr(delayed reactions) after challenge. The humoral immune response was determined by measuring hemagglutinins to SRBC. Histamine in varying concentrations($10^{-1},\;10^{-3}\;and\;10^{-5}M$(was added in SRBC suspension at the time of antigen challenge into footpad, and 24-hr delayed type hypersensitivity(DTH) was measured. Cimetidine in varying concentrations(10, 50, 250, 1250 and 6250${\mu}g$) enhanced 24-hr DTH and this enhancement of DTH was more pronounced at 250${\mu}g$ of cimetidine. However, there were no significant differences between the cimetidine-pretreated groups and controls in Arthus reaction and hemagglutinin titers. Histamine suppressed the DTH in the dose-dependent fashion. This suppression was more pronounced at lower concentration of immunizing antigen($10^7\;and\;10^6$ SRBC). However, histamine did not diminish the DTH at higher concentration of antigen($10^8$ SRBC). These results present the evidences which strongly suggest that cimetidine enhances the cell-mediated immune response but not significantlly influences the humoral immune response and that exogenous and endogenous histamine is involved in the modulation of cellular immune response as well as immediate hypersensitivity.

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Influence of Intracerebroventricular Yohimbine on the Renal Function of the Rabbit (가토 신장기능에 미치는 측뇌실내 Yohimbine의 영향)

  • Kook, Young-Johng;Kim, Kyung-Keun;Kim, Sei-Jong
    • The Korean Journal of Pharmacology
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    • v.21 no.2
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    • pp.119-127
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    • 1985
  • The renal function is under regulatory influence of the central nervous system, mainly through activation of sympathetic nerve to the kidney, and it was recently reported that clonidine, an agonist to ${\alpha}_2$-adrenoceptors, induces diuresis and natriuresis when injected directly into a lateral ventricle of the rabbit brain (i.c.v.). This study was undertaken, therefore, to obtain further information as to the role of the central ${\alpha}_2$-adrenoceptors in regulating renal function, by observing the effects of i.c.v. yohimbine, a specific antagonist of adrenoceptors of ${\alpha}_2$-type, on the rabbit renal function, and to elucidate the mechanism involved in it. With 10 ${\mu}g/kg$ i.c.v. of yohimbine sodium excretion transiently increased along with increasing tendency of urine flow, renal plasma flow and glomerular filtration rate. These responses decreased with increasing doses. With 100 and 300 ${\mu}g/kg$ i.c.v. marked antidiuresis and antinatriuresis as well as profound decreases of renal perfusion and glomerular filtration were noted. Systemic blood pressure transiently increased. In reserpinized rabbits, 100 ${\mu}g/kg$ yohimbine i.c.v. did not produce any significant changes in urine flow, sodium excretion as well as in renal hemodynamics. The pressor response was also abolished. In preparations in which one kidney was denervated and the other left intact as control, i.c.v. yohimbine elicited typical antidiuretic antinatriuretic response in the innervated control kidney, whereas the denervated experimental kidney responded with marked diuresis and increases in excretory rates of sodium and potassium and in osmolar clearance in spite of absence of increased filtration and perfusion . Systemic blood pressure responded as in the normal rabbits. These observations indicate that i.c.v. yohimbine affects renal function in dual ways in opposite directions, the first being the antidiuretic antinatriuretic effects which results from decreased renal perfusion and glomerular filtration due to sympathetic activation and which is predominantly expressed in the normal rabbits, and the second less apparent effect being the diuretic and natriuretic action which is not mediated by nerve pathway but brought about by some humoral mechanism and which is effected by decreased sodium reabsorption in the tubules, possibly of the proximal portion.

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Effect of Treadmill Exercise Training on the Expression of PGC-1α, GLUT-1, Tfam Proteins and Antioxydent Ezymes in Brain of STZ-Induced Diabetic Rats (트레드밀 지구성 운동이 streptozotocin으로 유발된 당뇨 흰쥐의 뇌에서 PGC-1α, GLUT-1, Tfam 단백질 및 항산화 효소(Cu, Zn-SOD, Mn-SOD)의 발현량에 미치는 영향)

  • Park, Noh-Hwan;Lee, Jin;Jung, Kook-Hyun;Choi, Bong-Am;Jang, Hyung-Chae;Lee, Suk-In;Lee, Dong-Soo;Cho, Joon-Yong
    • Journal of Life Science
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    • v.21 no.3
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    • pp.435-443
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    • 2011
  • The purpose of this study is to identify the effects of exercise training [ET, 10~18 m/min (speed), 20~30 min (exercise duration)/a day for 5 day/wk, 6 wk) on PGC-$1{\alpha}$, GLUT-1, Tfam, Cu,Zn-SOD and Mn-SOD proteins in brain of STZ-induced diabetic rats. The male Sprague-Dawley (SD) rats were single-injected intraperitoneally with 50mg/kg of streptozotocin (STZ) to produce STZ-induced diabetic rats. Rats were divided into 3 experimental groups with 8 rats in each group, as follows: (1) non-STZ group (n=8), (2) STZ-CON group (n=8), (3) STZ-EXE group (n=8). The results of this study suggest that i) serum glucose level was significantly reduced in STZ-EXE group compared with STZ-CON group (p<0.05), ii) PGC-$1{\alpha}$ (p<0.001), mtPGC-$1{\alpha}$ (p<0.001), GLUT-1 (p<0.001), and mtTfam (p<0.001) proteins in brain of STZ-induced diabetic rats were significantly increased in STZ-EXE group compared with STZ-CON group, iii) Cu,Zn-SOD (p<0.001) and Mn-SOD (p<0.01) proteins in the STZ-induced diabetic rats were significantly increased in STZ-EXE group compared with STZ-CON group. In conclusion, the findings of the present study reveal that treadmill exercise training increases brain GLUT-1 protein level possibly through up-regulation of PGC-$1{\alpha}$ and Tfam proteins which represent key regulatory components of stimulation of brain mitochondrial biogenesis. In addition, treadmill exercise training may prevent oxidative stress by up-regulation of Cu,Zn-SOD and Mn-SOD proteins in the STZ-induced diabetic rats.

IP-10 Decreases TNF-α Induced MUC5AC Expression in Human Airway Epithelial Cells: a Possible Relation with Little Sputum Production in Idiopathic Pulmonary Fibrosis (IP-10에 의한 기도상피세포에서의 TNF-α 유도 MUC5AC발현 억제: 특발성폐섬유증 환자의 적은 객담과의 연관성)

  • Kim, Seung Joon;Kang, Chun Mi;You, Moon Bin;Yoon, Hyung Kyu;Kim, Young Kyoon;Kim, Kwan Hyoung;Moon, Hwa Sik;Park, Sung Hak;Song, Jeong Sup
    • Tuberculosis and Respiratory Diseases
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    • v.64 no.5
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    • pp.347-355
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    • 2008
  • Background: IPF is characterized by chronic, fibrosing inflammatory lung disease of unknown etiology. Typical symptoms of IPF are exertional dyspnea with nonproductive cough. Why patients with typical IPF have dry cough rather than productive cough, is unknown. IP-10 plays an important regulatory role in leukocyte trafficking into the lung. The present study investigated the effect of IP-10 in the pathogenesis of dry cough rather than productive cough in IPF patients. Methods: IP-10 concentration was measured by ELISA from BALF of IPF patients. To evaluate the role of IP-10 in mucin expression, the expression of the MUC5AC mucin gene was measured in NCI-H292 cells, a human pulmonary mucoepidermoid carcinoma cell line, after stimulation by TNF-${\alpha}$ with or without IP-10 pretreatment. EGFR-MAPK expression was also examined as a possible mechanism. Results: IP-10 levels were significantly higher in the BALF of IPF patients compared to healthy controls. IP-10 pretreatment reduced TNF-${\alpha}$ induced MUC5AC mucin expression by inhibiting the EGFR-MAPK signal transduction pathway in NCI-H292 cells. Conclusion: These findings suggest that little mucus production in IPF patients might be attributable to IP-10 overproduction, which inhibits the EGFR-MAPK signal transduction pathway required for MUC5AC mucin gene expression.

Effects of GnRH Agonist Used for Ovarian Hyperstimulation in Human IVF-ET on the Apoptosis of Preovulatory Follicular Cells (인간 체외수정 및 배아이식에 있어서 과배란 유도 과정에 사용한 GnRH Agonist가 배란 전 난포내 과립 세포의 세포자연사에 미치는 영향)

  • Yang, Hyun-Won;Kwon, Hyuck-Chan;Hwang, Kyung-Joo;Park, Jong-Min;Oh, Kie-Suk;Yoon, Yong-Dal
    • Clinical and Experimental Reproductive Medicine
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    • v.26 no.1
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    • pp.55-65
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    • 1999
  • There have been many reports to date regarding the role of GnRH as a local regulatory factor of ovarian function as studies of human and rat ovaries revealed GnRH and its receptor. In recent studies it has been shown that GnRH directly causes apoptosis in the granulosa cells of the rat ovary, and such results leads to the suggestion that the use of GnRH agonist for more stable long term ovarian hyperstimulation in human IVF-ET programs causes granulosa cell apoptosis which may lead to follicular atresia. Therefore this study attempts to determine if granulosa-luteal cell apoptosis occurs in patients during IVF-ET programs in which GnRH agonist is employed for ovarian hyperstimulation. The quality of oocyte-cumulus complexes obtained during ovum pickup procedures were assessed morphologically and then the fertilization rate and developmental rate was determined. Apoptotic cells among the granulosa-luteal cells obtained during the same procedure were observed after staining with Hematoxylin-eosin. The fragmentation degree of DNA extracted from granulosa-luteal cells was determined and comparatively analyzed. There was no difference in the average age of the patients, the number of oocytes retrieved, and fertilization and developmental rates between the FSH/hMG group and GnRH-long group. There was also no difference in the apoptosis rate and pyknosis rate in the granulosa-luteal cells between the two groups. However, when the oocyte-cumulus complexes were morphoogically divided into the healthy group and atretic group without regard for the method of hyperstimulation, the results showed that the number of oocytes obtained averaged $11.09{\pm}8.75\;and\;10.33{\pm}4.53$ per cycle, respectively, showing no significant difference, but the fertilization rate (77.05%, 56.99%, respectively, p<0.01) and developmental rate (65.96%, 41.51%, respectively, p<0.01) was significantly increased in the healthy group when compared to the atretic group. The degree of apoptosis in the granulosa-luteal cells showed that in the healthy group it was 2.25% which was not significantly different from the atretic group (2.77%), but the pyknosis rate in the atretic group (27.81%) was significantly higher compared to the healthy group (11.35%, p<0.01). The quantity of DNA fragmentation in the FSH/hMG group was 32.22%, while in the GnRH-long group it was 34.27%, showing no significant difference. On the other hand the degree of DNA fragmentation was 39.05% and 11.83% in the healthy group and atretic group, respectively, showing significantly higher increase in the atretic group (p<0.01). The above results suggest that death of granulosa-luteal cells according to the state of the oocyte-cumulus complex is more related to pyknosis rather than apoptosis. Also, the GnRH agonist used in ovarian hyperstimulation does not seem to directly affect the apoptosis of retrieved oocytes and granulosa-luteal cells, and which is thought to be due to the suppression of the apoptogenic effect of GnRH agonist as a result of the high doses of FSH administered.

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Characteristics of PM2.5 and PM10 Concentration in Pusan Area (부산지역 PM2.5와 PM10의 농도 특성)

  • Kim, Sang-Youl;Cheong, Jang-Pyo;Yi, Seung-Muk
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.6
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    • pp.1159-1170
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    • 2000
  • It is necessary to improve the ambient air quality through the proper treatment and control of pollutants by designating air pollutants to regulatory ones. Especially, human took a concern for particulate matters which raised visibility reduction, public health effects and injury of property for urban areas. In order to reduce the effect of particulate matters, we need to establish proper control strategies based on the concentration characteristics of particulate matters. In this study. to evaluate the characteristics of $PM_{2.5}$ and $PM_{10}$. thirty-eight samples of $PM_{2.5}$ and $PM_{10}$ were collected at Nam-Gu sampling site where continuous air monitoring system has been operated, from May, 1999 to November, 1999, and their concentrations for the mass and anion components($Cl^-$, $NO_3{^-}$, $SO_4{^{2-}}$) were analyzed. The important conclusions obtained in this study were as followings. Total average mass concentrations of $PM_{2.5}$ and $PM_{10}$ were 35.016 and $50.293{\mu}g/m^3$ respectively. and $PM_{2.5}/PM_{10}$ ratio was calculated 0.692. Total average concentrations of anion components in $PM_{2.5}$ were $1.581(Cl^-)$, $3.690(NO_3{^-})$ and $12.825(SO_4{^{2-}}){\mu}g/m^3$ and those in $PM_{10}$ were $2.471(Cl^-)$, $5.819(NO_3{^-})$ and $14.414(SO_4{^{2-}}){\mu}g/m^3$ respectively. From the correlations analysis. the correlation coefficient between mass concentration of $PM_{2.5}$ and $PM_{10}$ was calculated as 0.945. The correlation coefficients between $PM_{2.5}$ and anion components were analyzed as $Cl^-$(0.025), $NO_3{^-}$(0.788) and $SO_4{^{2-}}$(0.500) respectively, and the correlation coefficients between $PM_{10}$ and anion components were analyzed as $Cl^-$(-0.019), $NO_3{^-}$(0.806) and $SO_4{^{2-}}$)(0.535) respectively.

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Operator exposure risk assessment of benzimidazole fungicides on Korean agricultural condition (Benzimidazole계 살균제의 농작업자 위해성평가)

  • Lee, Je-Bong;Shin, Jin-Sup;Jeong, Mi-Hye;Park, Yeon-Ki;Im, Geon-Jae;Kang, Kyu-Young
    • The Korean Journal of Pesticide Science
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    • v.9 no.4
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    • pp.347-353
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    • 2005
  • Pesticide risk assessment for pesticide operators as well as for consumers has become one of the pesticide regulatory tools to reduce any unreasonable adverse health effects from pesticide use. The risk for pesticide operators can be quantified by comparing the acceptable operator exposure level(AOEL) with exposure level during pesticide application. This study is to evaluate the risk of benzimidazole fungicides application worker. The exposure level of pesticide applicators were calculated using Japanese operator exposure study tested with EPN 45% EC. The AOELs for pesticides were obtained dividing relevant lowest no observed abuse effect levels(NOAELs) for the exposure scenario into uncertainty factor, 100. For the non-cancer and cancer occupational risk assessment, $Q_1^*$ produced by US/EPA and life time average daily dose(LADD) calculated from average daily dose(ADD), treatment days per year, worked years for life time were used. Operator exposure for benzimidazole fungicides application were benomyl 0.2, carbendazim 0.36 and thiophanate-methyl 0.42 mg/kg/day. Short-term AOELs for benomyl, carbendazim and thiophanate-methyl were 0.3, 0.1, and 0.2 mg/kg/day, and long-term AOEL were 0.025, 0.025, 0.08 mg/kg/day, respectively. LADDs were benomyl 0.0038, carbendazim 0.0067, thiophanate-methyl 0.0081 mg/kg/day. The ratios of exposure to AOEL were $0.28{\sim}1.5$ for short-term and $3.73{\sim}9.88$ for long-term. Cancer risk for operator were $9.12{\times}10^{-6}$ for benomyl, $1.61{\times}10^{-5}$ for carbendazim and $1.13{\times}10^{-4}$ for thiophanate-methyl by the standard application scenario. The result showed 3 fungicides exceed the risk criteria, $1.0{\times}10^{-6}$. The above risk assessments were based upon conservative assumptions and therefore are believed to be protective of the applicator. To refine the risk at the more actual conditions, further risk assessment with more realistic data would be needed.

Analytical Method Development for Determination of Silymarin by LC-MS/MS for Related Health Functional Foods (LC-MS/MS를 이용한 건강기능식품 중 실리마린 분석법 연구)

  • Oh, Mihyune;Lee, Jin Hee;Kim, Sang-A;Kim, Meehye
    • Journal of Food Hygiene and Safety
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    • v.33 no.2
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    • pp.124-130
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    • 2018
  • The Ministry of Food and Drug Safety (MFDS) is amending its test methods for the use of health functional foods (dietary food supplement), in order to establish regulatory standards and specifications in Korea. In this regard, we continue to pursue and perform our research on the analytical method development for the items being researched and reviewed. In this study, we have developed a sensitive and selective test method that could simultaneously separate and determinate six major bioactive flavonolignans in silymarin, which are based on the use of a liquid chromatographic-tandem mass spectrometry (LC-MS/MS). The standard calibration curves presented a linearity effect with the correlation coefficient ($r^2$) > 0.999. The limits of detection (LODs) and limits of quantitation (LOQs) were in the range of $0.3{\sim}9.0{\mu}g/L$ and $0.8{\sim}27.3{\mu}g/L$, respectively. The recovery results ranged between 96.2~98.6% at 3 different concentration levels, and its relative standard deviations (RSDs) were less than 5% as noted in this study. The proposed analytical method was characterized with a noted high resolution of the individual silymarin constituents, and the assay was fully validated as well. Our research can provide a significant scientific evidence that can be useful to amend the silymarin test method for the Health Functional Food Code.