• Journal of Preventive Medicine and Public Health
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• v.25 no.2 s.38
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• pp.180-188
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• 1992

The effects of multiple exposures to pesticides on plasma cholinesterase(ChE) activities and urinary p-nitrophenol excretion were evaluated in rats. Rats were received single dose i.p. with $LD_{50}/100(mg/kg)$ of organophosphorous(OP), organophosphorous-organochroline(OP-OC), organophosphorous-carbamate(OP-CAB), organophosphorous-organoarsenate(OP-OA) pesticides for 4 consecutive days. In repeated administration of pesticides, plasma ChE activities were decreased, but urinary p-nitrophenol were increased after the first injection and then decreased gradually The recovery rates of ChE activities and p-nitrophenol excretion at 48 hours after the fourth Injection were delayed in comparision with the baseline value of 24 hours before the first injection. Statistical significances were found between OP and other groups except OP-OA group after the second injection in plasma ChE activities, but in urinary p-nitrophenol excretion there was statistical significance only between OP and OP-CAB.

• Journal of Embryo Transfer
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• v.22 no.2
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• pp.81-87
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• 2007

The purpose of the present study was to determine the preventive effects of the two antioxidant vitamin E and catechin on DEHP-induced disturbance of spermatogenesis in male rats. Rats at 4 weeks of age were randomly allocated into five groups with 20 animals per group. The first group was not any administrated as control. The second group was administrated DEHP (2 g/kg) daily for 14 days. The third group was administrated vitamin E (500 IU/kg) following DEHP treatment by the same method (daily for 14 days). The fourth group was administrated catechin (200 mg/kg) following DEHP treatment by the same method. The fifth group was co-administrated vitamin E (500 IU/kg) and catechin (200 mg/kg) following DEHP treatment by the same method. In order to determine the preventive effects, we examined pathological changes of testis with apoptotic index, and characteristics of sperm with computer assisted sperm analysis (CASA). Vitamin E and catechin supplementation were significantly prevented the testicular atrophy, apoptosis of germ cells in the seminiferous tubules and abnormal rate of sperm. Moreover, sperm concentration, viability and motility was significantly recovered in groups of alone and along with vitamin E and catechin. The results suggest that preventive effects of alone and along administration of vitamin E and catechin on DEHP-induced testicular atrophy damages have been demonstrated.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.549-560
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• 2020

Although DNA damage responses (DDRs) are reported to be involved in nitric oxide (NO) production in response to genotoxic stresses, the precise mechanism of DDR-mediated NO production has not been fully understood. Using a genotoxic agent aphidicolin, we investigated how DDRs regulate NO production in bovine aortic endothelial cells. Prolonged (over 24 h) treatment with aphidicolin increased NO production and endothelial NO synthase (eNOS) protein expression, which was accompanied by increased eNOS dimer/monomer ratio, tetrahydrobiopterin levels, and eNOS mRNA expression. A promoter assay using 5'-serially deleted eNOS promoters revealed that Tax-responsive element site, located at -962 to -873 of the eNOS promoter, was responsible for aphidicolin-stimulated eNOS gene expression. Aphidicolin increased CREB activity and ectopic expression of dominant-negative inhibitor of CREB, A-CREB, repressed the stimulatory effects of aphidicolin on eNOS gene expression and its promoter activity. Co-treatment with LY294002 decreased the aphidicolin-stimulated increase in p-CREB-Ser¹³³ level, eNOS expression, and NO production. Furthermore, ectopic expression of dominant-negative Akt construct attenuated aphidicolin-stimulated NO production. Aphidicolin increased p-ATM-Ser¹⁹⁸¹ and the knockdown of ATM using siRNA attenuated all stimulatory effects of aphidicolin on p-Akt-Ser⁴⁷³, p-CREB-Ser¹³³, eNOS expression, and NO production. Additionally, these stimulatory effects of aphidicolin were similarly observed in human umbilical vein endothelial cells. Lastly, aphidicolin increased acetylcholine-induced vessel relaxation in rat aortas, which was accompanied by increased p-ATM-Ser¹⁹⁸¹, p-Akt-Ser⁴⁷³, p-CREB-Ser¹³³, and eNOS expression. In conclusion, our results demonstrate that in response to aphidicolin, activation of ATM/Akt/CREB/eNOS signaling cascade mediates increase of NO production and vessel relaxation in endothelial cells and rat aortas.

• Annals of Laboratory Medicine
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• v.38 no.6
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• pp.555-562
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• 2018

Background: The emerging mobile colistin resistance gene, mcr-1, is an ongoing worldwide concern and an evaluation of clinical isolates harboring this gene is required in Korea. We investigated mcr-1-possessing Enterobacteriaceae among Enterobacteriaceae strains isolated in Korea, and compared the genetic details of the plasmids with those in Escherichia coli isolates from livestock. Methods: Among 9,396 Enterobacteriaceae clinical isolates collected between 2010 and 2015, 1,347 (14.3%) strains were resistant to colistin and those were screened for mcr-1 by PCR. Colistin minimum inhibitory concentrations (MICs) were determined by microdilution, and conjugal transfer of the mcr-1-harboring plasmids was assessed by direct mating. Whole genomes of three mcr-1-positive Enterobacteriaceae clinical isolates and 11 livestock-origin mcr-1-positive E. coli isolates were sequenced. Results: Two E. coli and one Enterobacter aerogenes clinical isolates carried carried IncI2 plasmids harboring mcr-1, which conferred colistin resistance (E. coli MIC, 4 mg/L; E. aerogenes MIC, 32 mg/L). The strains possessed the complete conjugal machinery except for E. aerogenes harboring a truncated prepilin peptidase. The E. coli plasmid transferred more efficiently to E. coli than to Klebsiella pneumoniae or Enterobacter cloacae recipients. Among the three bacterial hosts, the colistin MIC was the highest for E. coli owing to the higher mcr-1-plasmid copy number and mcr-1 expression levels. Ten mcr-1-positive chicken-origin E. coli strains also possessed mcr-1-harboring IncI2 plasmids closely related to that in the clinical E. aerogenes isolate, and the remaining one porcine-origin E. coli possessed an mcr-1-harboring IncX4 plasmid. Conclusions: mcr-1-harboring IncI2 plasmids were identified in clinical Enterobacteriaceae isolates. These plasmids were closely associated with those in chicken-origin E. coli strains in Korea, supporting the concept of mcr-1 dissemination between humans and livestock.

• Korean Journal of Veterinary Service
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• v.38 no.4
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• pp.211-220
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• 2015

Many chemical disinfectants are using to protect the foot and mouth disease (FMD) and avian influenza (AI) in Korea since 2000. This study was performed to confirm disinfective ability of commercialized chemical disinfectants and to investigate the sterilizing ability of E-ball as alterative to chemical disinfectants. 4 kinds of acidulant, 3 kinds of aldehyde, 1 kind of oxidizer and 300 g of E-ball were used in this study. Dilution rate of disinfective power of all chemical disinfectants were to 200 times. The sterilizing ability of aldehydes were better than the acidulant and oxidizer with Salmonella typhimurium. The sterilizing ability of E-ball treated solution was guessed due to the friction of E-ball deads. In the case of the friction of 2 beads of E-ball, Salmonella typhimurium was sterilizted on $1{\times}10^6/mL$ CFU in the E-ball treated solution. The E-ball treated solution had superior sterizing power compared with the chemical disinfectants in the bacteria of soil for antibacterial examination. E-ball treated solution has a possibility as the substitute of chemical disinfectants to protective the animal diseases contains FMD, AI.

• The Journal of the Korean Society for Microbiology
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• v.18 no.1
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• pp.53-58
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• 1983

Enterotoxigenic E. coli is one of causative agents of the infantile diarrhea and traveler's diarrhea. A modified infant mouse assay(IMA) was developed for the detection of heat stable enterotoxin (ST) of E. coli isolated from diarrheal and control infants and assay system was established with using enterotoxin producing reference strains. The supernatant of the 24 hour-shaking culture of E. coli in Casamino Acid Yeast Extract Salt Broth(CYES-2) was ingested orally into the 2-4 day old ICR mice. After the mice were kept at $25^{\circ}C$ for 4 hours, they were sacrificed and the gut weight body weight ratio(GW/BW) was taken as the index of fluid accumulation induced by heat stable enterotoxin of E. coli. The results obtained were as follows; 1. The GW/BW responses of IMA tested with enterotoxin reference strains of E. coli(E. coli O148H28:$ST^+LT^+$, E. coli $O78H^-:ST^+LT^+$, E. coli O15H11:$ST^-LT^+$, E. coli O1H7:$ST^-LT^-$) appeared ta be ST dose-dependent, and not LT-dependent. From the dose-response curve, $25{\mu}l$ of culture supernatant was determined as test amount of the IMA. 2. Frequency distribution of IMA result from 643 strain of E. coli showed normal distribution at low GW/BW ratio and dispersed pattern at high GW/BW ratio. The GW/BW ratios of $0.056{\pm}0.004(mean{\pm}SD)$ of normal distribution which distributed from 0.044 to 0.068(P<0.01) was considered as ST negative. Thus the GW/BW ratio above 0.069 could be regarded as ST positive.

• Journal of Gastric Cancer
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• v.12 no.3
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• pp.140-148
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• 2012

Purpose: Among cell adhesion molecules, serum levels of intercellular adhesion molecule-1 and E-selectin are known to be correlated with the metastatic potential of gastric cancer. In the present study, the authors investigated the expression of intercellular adhesion molecule-1 and E-selectin in gastric cancer tissues and cultured gastric cancer cells, and examined their clinical value in gastric cancer. Materials and Methods: The protein was extracted from gastric cancer tissues and cultured gastric cancer cells (MKN-28 and Kato-III) and the expression of intercellular adhesion molecule-1 and E-selectin was examined by western blotting. The clinical significance of intercellular adhesion molecule-1 and E-selectin was explored, using immunohistochemical staining of specimens from 157 gastric cancer patients. Results: In western blot analysis, the expressions of intercellular adhesion molecule-1 in gastric cancer tissues and cultured gastric cancer cells were increased, however, E-selectin in gastric cancer tissues and cells were not increased. Among 157 gastric cancer patients, 79 patients (50%) were intercellular adhesion molecule-1 positive and had larger tumor size, an increased depth of tumor invasion, lymph node metastasis and perineural invasion. The intercellular adhesion molecule-1 positive group showed a higher incidence of tumor recurrence (40.5%), and a poorer 3-year survival than the negative group (54.9 vs. 85.9%, respectively). Conclusions: Intercellular adhesion molecule-1 is overexpressed in gastric cancer tissues and cultured gastric cancer cells, whereas E-selectin is not overexpressed. Increased expression of intercellular adhesion molecule-1 in gastric cancer could be related to the aggressive nature of the tumor, and has a poor prognostic effect on gastric cancer.

• The Journal of Korean Medicine
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• v.24 no.4
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• pp.25-33
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• 2003

lridology, a form of complementary and alternative medicine (CAM), is the diagnosis of medical conditions through noting irregularities of the pigmentation in the iris. lridological constitution has a strong familial aggregation and is implicated in heredity. Apolipoprotein E (apoE) gene polymorphism is one of the most well studied genetic markers of vascular disease. I investigated the relationship between iridological constitution and apoE polymorphism. I classified 87 hypertensive patients with family history of cerebral infarction and 79 controls according to iris constitution, and determined apoE genotype. Neurogenic type in hypertensives was 32.2% compared with 16.5% in controls (P<0.001). No differences in the apoE genotypes frequencies were observed in patients compared with those in controls ($x^2=0.726$, df-=2, P=0.696). However, in a population with ${\varepsilon}3/{\varepsilon}4$ genotype, the frequency of neurogenic constitution was significantly higher in hypertensives than in controls (60% vs. 0%) ($x^2=5.265$, df=l, P=0.022). These results could imply that apoE ${\varepsilon}3/{\varepsilon}4$ genotype and neurogenic iris constitution are risk factors for hypertension.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.416-425
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• 2009

Angiogenesis is important for promoting cardiovascular disease, wound healing, and tissue regeneration. We here investigated the pharmacological effects of Korea red ginseng water extract (KRGE) on angiogenesis and its underlying signal mechanism. This study showed that KRGE increased in vitro proliferation, migration, and tube formation of human umbilical endothelial cells, as well as stimulated in vivo angiogenesis. KRGE-induced angiogenesis was accompanied by phosphorylation of ERK1/2, Akt, and endothelial nitric oxide synthase (eNOS) as well as an increase in NO production. Inhibition of PI3K activity by wortmannin completely inhibited KRGE-induced angiogenesis and phosphorylation of Akt, ERK1/2, and eNOS, indicating that PI3K/Akt activation is an upstream event of KRGE-mediated angiogenic pathway. The MEK inhibitor PD98059 completely blocked KRGE-induced angiogenesis and ERK phosphorylation without affecting Akt and eNOS activation. However, the eNOS inhibitor NMA effectively inhibited tube formation, but partially blocked proliferation and migration as well as ERK phosphorylation without altering Akt and eNOS activation, revealing that eNOS/NO pathway is in part involved in ERK1/2 activation. This study first demonstrated the critical involvement of both ERK1/2 and eNOS activation in KRGE-induced angiogenesis, which lie on downstream of PI3K/Akt. Thus, these results indicate that KRGE requires activation of both the PI3K/Akt-dependent ERK1/2 and eNOS signal pathways and their cross-talk for its full angiogenic activity.

• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.137-142
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• 2015

Trimethoprim-sulfamethoxazole (TMP-SMX) has been used for the treatment of urinary tract infections, but increasing resistance to TMP-SMX has been reported. In this study, we analyzed TMP-SMX resistance genes and their relatedness with integrons and insertion sequence common regions (ISCRs) in uropathogenic gram-negative bacilli. Consecutive nonduplicate TMP-SMX nonsusceptible clinical isolates of E. coli, K. pneumoniae, Acinetobacter spp., and P. aeruginosa were collected from urine. The minimal inhibitory concentration was determined by Etest. TMP-SMX resistance genes (sul and dfr), integrons, and ISCRs were analyzed by PCR and sequencing. A total of 45 E. coli (37.8%), 15 K. pneumoniae (18.5%), 12 Acinetobacter spp. (70.6%), and 9 Pseudomonas aeruginosa (30.0%) isolates were found to be resistant to TMP-SMX. Their MICs were all over 640. In E. coli and K. pneumoniae, sul1 and dfr genes were highly prevalent in relation with integron1. The sul3 gene was detected in E. coli. However, in P. aeruginosa and Acinetobacter spp., only sul1 was prevalent in relation with class 1 integron; however, dfr was not detected and sul2 was less prevalent than in Enterobacteriaceae. ISCR1 and/or ISCR2 were detected in E. coli, K. pneumoniae, and Acinetobacter spp. but the relatedness with TMP-SMX resistance genes was not prominent. ISCR14 was detected in six isolates of E. coli. In conclusion, resistance mechanisms for TMP-SMX were different between Enterobacteriaceae and glucose non-fermenting gram-negative bacilli. Class 1 integron was widely disseminated in uropathogenic gram-negative baciili, so the adoption of prudent use of antimicrobial agents and the establishment of a surveillance system are needed.