• Journal of Environmental Health Sciences
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• v.38 no.6
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• pp.510-519
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• 2012

Objectives: This study was conducted in order to evaluate the microbiological contamination of the indoor air of the lunchrooms at child care centers and investigate the toxin genes and toxin production ability of food-borne pathogens. Methods: A total of 64 child care centers were sampled to test total aerobic bacteria, coliform bacteria, fungi, Staphylococcus aureus, Bacillus cereus and Salmonella spp. according to the Korea Food Code. All toxin genes of pathogens were detected using the Polymerase Chain Reaction method. The Sthaph. aureus enterotoxin was detected by a Staphylococcus aureus enterotoxin-reversed passive latex agglutination kit. The heamolysin BL (HBL) and non-heamolytic enterotoxin (NHE) produced by B. cereus were detected using a B. cereus enterotoxin-reversed passive latex agglutination kit and Bacillus diarrheal enterotoxin visual immunoassay kit, respectively. Results: The means of total aerobic bacteria and coliform bacteria were $1.91{\pm}1.84$ log CFU/plate and $0.47{\pm}0.62$ log CFU/plate, respectively. The mean of fungi also showed $0.59{\pm}0.71$ log CFU/plate. Among the pathogenic bacteria tested in this study, Staphy. aureus and B. cereus were detected in four (6.3%) and 21 (32.8%) out of 64 indoor air samples from lunchrooms in child care centers, respectively. All Staphy. aureus tested in this study possessed no toxin genes and did not produce enterotoxin. The detection rate of nheABC, hblCDA, entFM and ces toxin gene in B. cereus was 100, 57.1, 76.2 and 0%, respectively. B. cereus isolates were classified into four groups according to the presence or absence of toxin genes. The nheABC gene was the major toxin gene among B. cereus tested in this study. The HBL was detected in 11 out of 21 B. cereus isolates (52.4%) and three B. cereus isolates produced NHE (14.3%). Conclusion: The results indicated that the contamination by microorganisms in the indoor air of lunchrooms was unqualified to supply safe catering in child care centers. The ongoing control of indoor air quality is required.

• Journal of Food Hygiene and Safety
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• v.19 no.3
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• pp.161-166
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• 2004

We investigated the antiplatelet effect of a newly synthesized guanidine derivative KR-32558, a sodium-hydrogen exchanger-1 (NHE-1) inhibitor, together with the elucidation of the possible mechanisms of action. KR-32558 concentration -dependently inhibited the aggregation of washed rabbit platelets induced by collagen (10 ${\mu}g/ml$) with an $IC_{50}$ value of 85.9 ${\mu}M$, but with much weaker potency against aggregation induced by thapsigargin (0.5 ${\mu}M$) or A23187 (5 ${\mu}M$). And had no effect on platelet aggregation induced by arachidonic acid (100 ${\mu}M$), thrombin (0.05 U/ml) and U46619 (1 ${\mu}M$) up to 100 ${\mu}M$. KR-32558 completely inhibited the $[Ca^{2+}]_i$ mobilization induced by collagen at concentration of 100${\mu}iM$. Taken together, these observation suggest that KR-32558 selectively inhibited collagen-mediated platelet aggregation by blocking the cytoplasmic calcium mobilization in addition to NHE-1 inhibition.

• The Journal of Pediatrics of Korean Medicine
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• v.38 no.1
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• pp.1-9
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• 2024

Objective The purpose of this study was to confirm the effects of Galgeunhwanggeumhwangryeon-tang (PSCG) extract on skin moisturizing, antibacterial, and tight junction recovery in atopic dermatitis-induced mice. Methods In this study, we used 4-week-old NC/Nga mice divided into four groups: control (Ctrl), lipid barrier elimination (LBE), dexamethasone (Dx) after lipid barrier elimination (DEX), and PSCG after lipid barrier elimination (PSC). Ten rats were assigned to each treatment group. Three days after drug administration following lipid barrier elimination, ceramide kinase, caspase 14, sodium hydrogen antiporter (NHE), cathelicidin, claudin, and toll-like receptor (TLR)-2 were observed to confirm the restoration of skin moisturizer production, antimicrobial barriers, and tight junctions in the skin barrier. Results Ceramide kinase and caspase 14 positive reaction were significantly higher in PSC than in LBE and DEX. Both NHE and cathelicidin showed higher positive reactions in PSC than in LBE and DEX. Claudin, and TLR-2 showed higher levels of positive staining in the PSC group than in the LBE and DEX groups. Conclusion It was confirmed that the PSCG extract can have the potential to restore the damaged skin barrier in atopic dermatitis.

• Archives of Pharmacal Research
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• v.29 no.5
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• pp.375-383
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• 2006

The anti platelet effects of a novel guanidine derivative, KR-32570 ([5-(2-methoxy-5-chlorophenyl) furan-2-ylcarbonyl]guanidine), were investigated with an emphasis on the mechanisms underlying its inhibition of collagen-induced platelet aggregation. KR-32570 significantly inhibited the aggregation of washed rabbit platelets induced by collagen $(10{\mu}g/mL)$, thrombin (0.05 U/mL), arachidonic acid $(100{\mu}M)$, a thromboxane (TX) $A_2$ mimetic agent U46619 (9,11-dideoxy-9,11-methanoepoxy-prostaglandin $F_2,\;1{\mu}M$) and a $Ca^{2+}$ ATPase inhibitor thapsigargin $(0.5{\mu}M)$ ($IC_{50}$ values: $13.8{\pm}1.8,\;26.3{\pm}1.2,\;8.5{\pm}0.9,\;4.3{\pm}1.7\;and\;49.8{\pm}1.4{\mu}M$, respectively). KR-32570 inhibited the collagen-induced liberation of $[^3H]$arachidonic acid from the platelets in a concentration dependent manner with complete inhibition being observed at $50{\mu}M$. The $TXA_2$ synthase assay showed that KR-32570 also inhibited the conversion of the substrate $PGH_2$ to $TXB_2$ at all concentrations. Furthermore, KR-32570 significantly inhibited the $[Ca^{2+}]_i$ mobilization induced by collagen at $50{\mu}M$, which is the concentration that completely inhibits platelet aggregation. KR-32570 also decreased the level of collagen $(10{\mu}g/mL)$induced secretion of serotonin from the dense-granule contents of platelets, and inhibited the NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. These results suggest that the antiplatelet activity of KR-32570 against collagen-induced platelet aggregation is mediated mainly by inhibiting the release of arachidonic acid, $TXA_2$ synthase, the mobilization of cytosolic $Ca^{2+}$ and NHE-1.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.50-56
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• 2017

The purpose of this study was to investigate the microbiological contamination of water and drinking cups in springs and to estimate the toxin gene, enterotoxin production ability and antibiotic susceptibility of foodborne pathogens. Ten spring water and 34 drinking cups were tested. The average number of total aerobic bacteria and coliform bacteria in spring water were 1.8 log CFU/mL and 1.2 log CFU/mL, and in drinking cups were $4.7log\;CFU/100cm^2$ and $1.7log\;CFU/100cm^2$. Salmonella spp., Staphylococcus aureus, E. coli O157:H7, Listeria monocytogenes, Vibrio parahaemolyticus, Yersinia enterocolitica were not isolated from all of samples but Bacillus cereus was detected in 5 (14.7%) of 34 drinking cups. The nheA and entFM genes were major enterotoxin genes in B. cereus isolated from drinking cups. All of B. cereus tested in this study produce non-heamolytic enterotoxin but only 2 isolates possessed heamolysin BL enterotoxin producing ability. B. cereus was resistant to ${\beta}-lactam$ antibiotics. These results revealed that the sanitary conditions of drinking cups in spring should be improved promptly. The substitution carrying a personal drinking cup for the public drinking cups equipped in springs is suggested to prevent food-borne illness.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.44-55
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• 2016

Bacillus cereus is a gram-positive, rod-shaped, spore-forming bacterium that has been isolated from contaminated fermented soybean food products and from the environment. B. cereus produces diarrheal and emetic toxins and has caused many outbreaks of foodborne diseases. In this study, we investigated whether B. amyloliquefaciens RD7-7, isolated from rice doenjang (Korean fermented soybean paste), a traditional Korean fermented soybean food, shows antimicrobial activity against B. cereus and regulates its toxin gene expression. B. amyloliquefaciens RD7-7 exhibited strong antibacterial activity against B. cereus and inhibited the expression of B. cereus toxin-related genes (groEL, nheA, nheC, and entFM). We also found that addition of water extracts of soybean and buckwheat soksungjang (Korean fermented soybean paste made in a short time) fermented with B. amyloliquefaciens RD7-7 significantly reduced the growth and toxin expression of B. cereus. These results indicate that B. amyloliquefaciens RD7-7 could be used to control B. cereus growth and toxin production in the fermented soybean food industry. Our findings also provide a basis for the development of candidate biological control agents against B. cereus to improve the safety of fermented soybean food products.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.219-224
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• 2020

The purpose of this study was to provide basic data necessary for the prevention of food poisoning and safe food management. We examined 872 food samples for B. cereus in accordance with the MFDS Food Code and investigated characteristics of their harboring toxin genes. We detected and isolated 113 strains of B. cereus from 78 food samples (8.9%), and the average detection level was 48 CFU/g. B. cereus isolates carried at least 1 toxin gene among the emetic toxins and 5 enterotoxin genes. The toxin gene profiles of B. cereus were classified into 18 different types of isolates showing genetic diversity. Among the strains, 34 (30.1%) had all 5 enterotoxin genes (Cytk-nheA-entFM-bceT-hblC), accounting for the highest percentage. The entFM and nheA genes were major enterotoxin genes, while the emetic toxin gene, CER, was the least detected in B. cereus isolated from food samples.

• 대한약리학회:학술대회논문집
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• 2006.10a
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• pp.93.2-93.2
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• 2006

• Development and Reproduction
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• v.17 no.3
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• pp.289-297
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• 2013

Bisphenol A (BPA) is an estrogenic endocrine disrupter. However, depending on a way of treatment, the harmful effects of BPA have not been confirmed. Also, trans-generational effects of BPA on male reproduction are still controversial. Because the reabsorption of testicular fluid in the efferent ductules (ED) and initial segment (IS) is important for sperm maturation, the present study was designed to determine trans-generational effect of BPA administrated orally on expression of water transport-related molecules in the mouse ED and IS. Ethanol-dissolved BPA was diluted in water to be 100 ng (low), $10{\mu}g$ (medium), and $1mg/m{\ell}$ water (high). BPA-containing water was provided for two generations. Expression of ion transporters and water channels in the ED and IS were measured by relative real-time PCR analysis. In the ED, BPA treatment caused expressional increases of carbonic anhydrase II, cystic fibrosis transmembrane regulator, $Na^+/K^+$ ATPase ${\alpha}1$ subunit, and aquaporin (AQP) 1. No change of $Na^+/H^+$ exchange (NHE) 3 expression was detected. BPA treatment at medium dose resulted in an increase of AQP9 expression. In the IS, the highest expressional levels of all molecules tested were observed in medium-dose BPA treatment. Generally, high-dose BPA treatment resulted in a decrease or no change of gene expression. Fluctuation of NHE3 gene expression by BPA treatment at different concentrations was detected. These findings suggest that trans-generational exposure to BPA, even at low dose, could affect gene expression of water-transport related molecules. However, such effects of BPA would be differentially occurred in the ED and IS.

• Bulletin of the Korean Chemical Society
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• v.19 no.9
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• pp.897-906
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• 1998

A new synthesis has been developed for 1-thia-4,7-diazacyclononane and the complexation behavior of a particular derivative has been explored. The pentadentate ligand 4,7-bis(2-pyridylmethyl)-l-thia-4,7-diazacyclononane ([9]$N_2SPY_2$) and its iron(Ⅱ) and manganese(Ⅱ) complexes were prepared and characterized. Magnetic moments of 5.17 and 5.90 μB respectively, indicate that the iron(Ⅱ) and manganese(Ⅱ) complexes are high spin. Charge transfer transitions (d-π*) occur for [Fe(Ⅱ)([9]$N_2SPY_2)(X)]^{n+}$at 27027, 25000, and 24390 cm-1 for X=$H_2O$, Cl-, and OH-, respectively. In acetonitrile solution, the cyclic voltammogram of the manganese(Ⅱ) complex exhibits a redox couple at 0.92 V vs. NHE while the redox potentials for [Fe(Il)([9]$N_2SPY_2)(X)]^{n+}$ are 0.70, 0.66, and 0.37 V vs. NHE for X=$H_2O$, Cl-, and OH-, respectively. The d-π* charge transfer energy and Fe(Ⅱ)/Fe(Ⅲ) redox potential for [Fe(Ⅱ)([9]$N_2SPY_2)(X)]^{n+}$ increase in the same order: $H_2O>Cl^- >OH^-$. The crystal structures of the iron(Ⅱ) and manganese(Ⅱ) complexes reveal that the metal ions are sixcoordinate, binding to four nitrogen atoms and a sulfur atom from the pentadentate ligand, as well as a chloride anion, with the chloride and sulfur atoms in cis positions. The two metals have similar coordination geometries, which are closer to trigonal prismatic than octahedral. In both iron and manganese complexes, the M-N($sp_3$) trans to Cl- is 0.07 Å longer than the one cis to Cl- , and M-N($sp^2$) trans to S is 0.05 longer than the one cis to S atom.