• BMB Reports
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• v.33 no.6
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• pp.463-468
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• 2000

Anthrax lethal toxin, which consists of two separate protein, protective antigen (83 KDa) and lethal factor (85 KDa) is responsible for major symptoms and death from systemic infection of Bacillus anthracis. High concentrations of this toxin are cytolytic to macrophages, whereas sublytic concentrations of lethal toxin induce these cells to produce interleukin $1{\beta}$ ($IL-1{\beta}$). It is proposed that melatonin and dehydroepiandrosterone (DHEA) may play an important role in modifying immune dysfunction. In this study, we investigated whether or not melatonin and DHEA could prevent $IL-1{\beta}$ production that is induced by anthrax lethal toxin in mouse peritoneal macrophages. Treatment of melatonin or DHEA alone, as well as together, prevented the production of $IL-1{\beta}$ caused by anthrax lethal toxin. We found that melatonin at a concentration of $10^{-6}-10^{-7}$ M inhibits $IL-1{\beta}$ production induced by anthrax lethal toxin. As expect, treatment of DHEA at a concentration $10^{-6}-10^{-7}$ M also suppressed production of $IL-1{\beta}$ by lethal toxin stimulated macrophages. The results of these studies suggest that melatonin and DHEA, immunomodulators, may have an important role in reducing the increase of cytokine production in anthrax lethal toxin-treated macrophages.

• Journal of Preventive Medicine and Public Health
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• v.27 no.4 s.48
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• pp.693-709
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• 1994

This epidemiologic study was carried out to investigate cauuse and magnitude of food-poisoning like epidemic occurred among inhabitants of a village who have eaten dead cow's meat near Kyongju in February of 1994, around lunar new year, The investigation consisted of interview survey on all inhabitants of 77 households (111 males and 119 females) and their visitors (40 males and 35 females), skin test with anthraxinum (Russian product), study on clinical characteristics for the patients hospitalized, and microbiologic examination on microbes isolated from cow's meat, patient and soils of dead cow's barn. The results obtained are as followings; 1. The proportion of the inhabitants who ingested the dead cow's meat was 36.4%. The incidence rate of the disease was 65.1% for males, 41.7% for females and the cases were distributed evenly for all age groups. The group ingested raw meat showed higher incidence than the group ingested cooked meat. There was no case among people who did not eat the meat. 2. The most clinical symptoms were significantly more frequent among cases than non-cases : sore throat (57%), nausea (51%), fever (47%), indigestion (43%), cough (41%), anorexia (41%), abdominal distention (41%), and abdominal pain (39%) were the major symptoms among cases. 3. Among 29 cases hospitalized out of total 61 cases, three patients, all old and feeble persons, deceased from the disease resulting in 4.9% fatality rate among total patient and 10.3% among hospitalized. Septicemia and meningitis were the causes of the deaths. 4. Three strains isolated from patients, and three strains from dead cow's meat and soil revealed typical microbiologic characteristics of Bacillus Anthracis, which also proved to be fatal to experimentally infected mice.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.195-198
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• 2006

Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.

• Korean Journal of Veterinary Service
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• v.45 no.2
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• pp.117-124
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• 2022

In the event of an outbreak of a livestock epidemic, it has been considered that the existing burial-centered carcass disposal method should be improved ecofriendly for prevention of leachate and odors from burial basically in regard of pathogen inactivation. Therefore, the aim of this study is whether it was possible to treat the carcass of cattle and chickens using the chemical carcass treatment method. It was conducted to establish detailed treatment standards for the chemical treatment method of cattle and chicken carcasses based on the results of the proof of the absence of infectious diseases in cattle chickens. After inoculating cattle carcass with 10 pathogens (foot and mouth disease virus, bovine viral diarrhea virus, Mycobacterium bovis, Mycobacterium avium subsp. Paratuberculosis, Brucella abortus, Bacillus anthracis, Clostridium chauvoei, Clostridium perfringens, Escherichia coli, and Salmonella Typhimurium) and chicken carcasses with low pathogenic avian influenza virus, Clostridium perfringens type C, E. coli and Salmonella Typhimurium, these were treated at 90℃ for 5 hours in a potassium hydroxide liquid solution corresponding to 15% of the body weight. This method liquefies all cadaveric components and inactivates all inoculated pathogens by PCR and culture. Based on these results, it was possible to prove that chemical treatment of cattle and chicken carcasses is effective in killing pathogens and is a safe method without the risk of disease transmission. The chemical treatment method of livestock carcasses can be suggested as an alternative to the current domestic burial-centered livestock carcass treatment method, preventing environmental pollution, and contributing to public health.