• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.375-380
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• 2000

The preliminary screening of several cyanobacteria, using mice bioassay, reveale the production of a hepatotoxin by the cyanobacterium Scytonema sp. strain BT 23 isolated from soil. An intraperitoneal injection of the crude toxin (LD50 56 mg/kg body wt) from this strain caused the death of the mice within 40 min, and the anmals showed slinical signs of mice within 40 min, and the animals showed clinical signs of hepatotoxicity. The toxin was purified and partially characterized. The active fraction appears to be nonpolar in nature and shows absorption peaks at 240 and 285 nm. The purified toxin had an LD50 of TEX>$100<\mu\textrm{g}/kg$ body wt and the test mice died within 40 min of toxin administration. The toxin-treated mice showed a 1.65-fold increase in liver weight at 40 min and the liver color chnged to dark red due to intrahepatic hemorrhage and pooling of blood. Furthermore, the administration of the toxin to test mice induced a 2.58, 2.63, and 2.30-fold increse in the activity of the serum enzymes alanine aminotransferase, lactate dehydrogenase, and alkaline phosphatase, respectively. Further experiments with the 14C-labeled toxin revealed a maximum accumulation of the toxin in the liver. The clinical symptoms in the mice were similar to those produced by microcystin-L.R. These results suggest that hepatotoxins may also be produced in non bloom-forming planktonic cyanobacteria.

• Archives of Pharmacal Research
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• 제15권2호
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• pp.146-151
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• 1992

The aim of this study was to evaluate capability of pertussis toxin (PT) to active mouse macrophages. The investigations were undertaken to determine whether the role played by this toxin required the A-protomer of the toxin to ADP-ribosylate a guanine nucleotide binding protein (a class I activity) or was dependent on the binding of B-oligomer of the toxin to the surface of target cells (a Class II activity). The results of these experiments have established that the mechanism of macrophage activation with PT seems to be dependent upon a Class II activity of the toxin.

• 한국식품위생안전성학회지
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• 제3권2호
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• pp.65-73
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• 1988

종래의 화학적, 생물학적 분석방법의 단점인 검출한도가 낮은점, 시료전처리의 복잡성, 비경제성 및 비 특이성 등을 극복하기 위해 monoclonal AB를 사용한 ELISA법으로 T-2 toxin 에 대해 특이성있는 새로운 분석법을 개발하여 다음과 같은 결과를 얻었다. 1. 종래의 GLC 및 GC-MS 분석법보다 간편하고 신뢰성이 높으며 검출한계가 0.1ppb인 고감도의 분석법을 개발하였다. 2. 본 분석법을 이용하여 Fusarium spp. 균의 T-2 생산유무를 단시간에 다량의 시료를 검색할 수 있었으며, data의 정확도가 GLC와 유사하며 GLC로는 검색할 수 없는 150ppb이하의 미량함유 시료에서도 T-2 toxin을 검색할 수 있었다. 3. 본 실험에 사용한 F. sporotichioides M-1-1 균주의 밀에 대한 최적 배양조건은 $24~27^{\circ}C$ 2주간임을 알았다.

• 미생물학회지
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• 제30권3호
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• pp.160-163
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• 1992

원형질체 융합을 통하여 육성한 killer 효모 융합주 FWKS 260 의 killer toxin 을 ammonium sulfate fractionation, Amicon PM 10 concentration, Sephadex G-200 및 Sephadex G-75 column chromatography 를 행하여 정제한 결과 단일 단백질 band 를 보여 순수하게 정제되었음을 알 수 있었고, 단백질 분해효소를 처리한 결과 killer 활성이 소실되어 killer toxin 의 단백질 부분이 killer 활성을 나타냄을 알 수 있었다. 그리고 이 toxin 은 20.deg.C 에서는 거의 안정하였으나, 온도가 증가함에 따라 점차 활성이 소실되었고, pH 2.0-5.0 에서 비교적 안정하였다. 한편, SDS-polyacrylamide gel electrophoresis 결과 분자량은 약 13.000 임을 알 수 있었고, SDS polyacrylamide gel electrophoresis 를 행한 후 Schiffs reagent 로 염색한 결과 붉은 단일 band 를 보여 정제된 killer toxin 은 glycoprotein 임을 확인 할 수 있었다.

• 한국식품위생안전성학회지
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• 제27권1호
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• pp.1-17
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• 2012

T-2 toxin and HT-2 toxin, belong to type A trichothecences, are the most toxic mycotoxins among the trichothecene family. These mycotoxins are commonly found in cereals such as maize, wheat, barley, oats and rice, and their occurrence in food can be of concern. This review investigated the current trends of patents and researches on T-2 toxin and HT-2 toxin pertaining to natural occurrence, toxicity, metabolism, risk assessment, analytical and screening methods, and reduction/detoxification techniques. As compared with other $Fusarium$ mycotoxins, there are limited data for natural occurrence and risk assessment, and regulatory limit and official analytical methods on T-2 toxin and HT-2 toxin in domestic and foreign countries. In particular, selective deacetylation at the C3 and/or C4 positions of T-2 toxin by carboxyesterase present in foods was reported to cause the disappearance of T-2 and the extremely high HT-2 recoveries. Currently, regulatory limits for T-2 and HT-2 are under discussion in EU. For enforcement purposes it is essential to have available precise and reliable analytical methods applicable at the regulatory levels for the T-2 toxin and HT-2 toxin and relevant commodities. In addition, a further study on natural occurrence, risk assessment and reduction/detoxification techniques will be recommended.

• 한국전문물리치료학회지
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• 제5권1호
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• pp.44-50
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• 1998

The purpose of this case study was to introduce botulinum toxin A injection in cerebral palsy. Spasticity can be managed using a variety of methods. Eliminating aggravating sources, promoting stretching and bracing, and positioning are the least invasive methods of treatment. Botulinum toxin A injection is a relatively recent method of spasticity management in children with cerebral palsy. A 3-year old boy was evaluated for possible botulinum toxin injection to promote left side function. The patient had left hemiparetic cerebral palsy. He walked with bilateral intoning, much worse on the left than on the right and with excessive plantar flexion on the left. Botulinum toxin A was injected into the left medial gastrocnemius, with the goals of improving quality of gait. Finally, botulinum toxin treatment of would improve the motor function and ambulatory status in cerebral palsy by hypertonicity, spasticity, dynamic contracture and athetoid movement.

• Archives of Pharmacal Research
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• 제27권6호
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• pp.640-645
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• 2004

Histone deacetylase inhibitors are new class of chemotherapeutic drugs able to induce tumor cell apoptosis and／or cell cycle arrest. Trichostatin A, an antifungal antibiotic, and HC-toxin are potent and specific inhibitors of histone deacetylase activity. In this study, we have examined the antiproliferative activities of trichostatin A and HC-toxin in estrogen receptor positive human breast cancer, T47D cells. Both trichostatin A and HC-toxin showed potent antiprolifer-ative efficacy and cell cycle arrest at $G_2/M$ in T47D human breast cancer cells in a dose-dependent manner. Trichostatin A caused potent apoptosis of T47D human breast cancer cells and trichostatin A-induced apoptosis might be involved in an increase of caspase-3／7 activity. HC-toxin evoked apoptosis of T47D cells and HC-toxin induced apoptosis might not be medi-ated through direct increase in caspase-3/7 activity. We have identified potent activities of anti-proliferation, apoptosis, and cell cycle arrest of trichostatin A and HC-toxin in estrogen receptor positive human breast cancer cell line T47D.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.522.2-522
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• 1986

In order to optimally induce sporulation and toxin formation in Bacillus thuringiensis, exhaustion of specific nutrients as well as resuspension experiments were tried. Sporulation and toxin formation was most abunduntly occurred when the growth was limited by carbon source. It was also occurred in a resuspension medium containing only distilled water. Various environmental and physiological factors affecting the efficiencies of spore and toxin formation were examined in chemically defined media. As a result of these studies, a batch fermentation resulted in higher spore and toxin yield than ever reported

• Journal of Microbiology and Biotechnology
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• 제22권2호
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• pp.170-175
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• 2012

Clostridium difficile toxin A glucosylates Rho family proteins, resulting in actin filament disaggregation and cell rounding in cultured colonocytes. Given that the cellular toxicity of toxin A is dependent on its receptor binding and subsequent entry into the cell, we herein sought to identify additional colonocyte proteins that might bind to toxin A following its internalization. Our results revealed that toxin A interacted with ERK1 and ERK2 in two human colonocyte cell lines (NCM460 and HT29). A GST-pulldown assay also showed that toxin A can directly bind to ERK1 and ERK2. In NCM460 cells exposed to PMA (an ERK1/2 activator), the phosphorylation of ERK1/2 did not affect the interaction between toxin A and ERK1/2. However, an in vitro kinase assay showed that the direct binding of toxin A to ERK1 or ERK2 inhibited their kinase activities. These results suggest a new molecular mechanism for the cellular toxicity seen in cells exposed to toxin A.

• 생약학회지
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• 제16권3호
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• pp.129-135
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• 1985

In order to search for potential antidotes for T-2 toxin poisoning, seven Chinese herbal drug extracts and five natural constituents were tested on mice intoxicated with T-2 toxin. When extracts of Panax ginseng and Atractylodes japonica (500 mg/kg) were administered p.o. once 3 hrs before and once 1 hr after T-2 toxin treatment, a 30% complete survival rate was noted. In case of Paeonia albiflora var. typica, a 30% complete survival rate was also produced at a dose of 250 mg/kg. Other extracts, Glycyrrhiza uralensis, Scutellaria baicalensis, Rehmannia glutinosa and Plantago asiatica exhibited no significant protection from the T-2 toxin poisoning. A nucleoside, thymidine showed protective activity against T-2 toxin toxicity and it produced a 40% complete survival rate when administered i.p. once 0.5 hr after T-2 toxin treatment. Other natural constituents, aucubin, vitamin C and E, and lipoic acid did not show any significant protective activities.