Disruption of rsmA Gene of Pectobacterium carotovorum subsp. carotovorum LY34 and Effect on Pathogenicity

Kim, Min Keun,Kang, Tae Ho,Kim, Sung Kyum,Jeong, Yu Seok,Yun, Han Dae,Kim, Hoon The Korean Society for Applied Biological Chemistr 2012 Applied Biological Chemistry (Appl Biol Chem) Vol.55 No.6

The rsmA gene was cloned from soft-rot bacterium Pectobacterium carotovorum subsp. carotovorum LY34 (Pcc LY34), and its role in pathogenicity was investigated by marker exchange mutagenesis. From a cosmid library of Pcc LY34 genomic DNA, a positive clone carrying the rsmA gene was selected, and the gene was cloned by polymerase chain reaction (PCR) amplification. The gene is 186 bp in size and encodes a protein of 62 amino acids with a predicted molecular mass of 6,839 Da. The calculated pI of the RsmA is 8.16. The phylogenetic tree showed that the RsmA of Pcc LY34 appeared genetically identical to the CsrA of Pectobacterium atrosepticum SCRI1043 (100% identity) and similar to the CsrA of Yersinia pestis KIM10+(98.3%). The gene was disrupted by the $Km^r$ gene, and the cells became mutated (i.e., $RsmA^-$ mutant). The pathogenicity test revealed that the disease rating of the $RsmA^-$ mutant only differed slightly from that of the wild type on a slice of potato tuber and a Chinese cabbage stalk. These results suggest that RsmA is not an essential factor for the pathogenicity of Pcc LY34 and that the rsmA gene of Pcc LY34 is not completely derepressed in the $RsmA^-$ mutant for virulence-related genes, contrary to the results of Erwinia carotovora subsp. carotovora $RsmA^-$ mutant, which proved hypervirulent for celery petioles. These results showed that the microenvironmental conditions of the host and/or strain of pathogen are important for the coordination of virulence gene expression.

수면량과 집중력의 상관관계

김병우,류지근,박우진,박계원,김미정,임지은,백대현,최재덕,최윤호,이가현,이관,김덕수 東國大學校醫學硏究所 2002 東國醫學 Vol.9 No.1

수면, 기억 그리고 학습의 연관성은 실제 매우 복잡하다. 많은 연구에도 불구하고 명확한 연구결과는 아직 없다. 우리는 이 연구에서 평소와는 달리 시험 전날 수면 변화 양상이 집중력에 어느 정도 영향력을 미치는지 알아보고자 하였고, 이를 이용해 효율적인 수면 관리를 할 수 있는 기초자료로 삼고자 하였다. 동국대 의대 본과 1학년생 중 지원자 30명과 본과 2학년생 10명을 대상으로 평상시 상태와 시험 직후 수면이 부족한 상태에서 각각 K-PES TEST를 실시하여 총 8항목에 걸쳐 암기력, 판단력, 단순반응의 변화정도를 검사하였다. 또 설문조사를 병행하여 결과에 영향을 미칠 수 있는 다른 인자들도 파악하였다. 수면량에 대한 부호 숫자 짝짓기(순간 판단력)을 검사한 결과, 인간의 최대 생리학적 기능은 꼭 수면부족에 의해 좌우되는 것은 아니다. 그러나, 수면감소는 피로를 증가시키고, 동기부여를 감소시키나 단, 새로운 사실을 학습하는 데에는 큰 영향을 끼치지 않는다. 즉, 수면부족으로 장시간 깨어있는 것은 정확성과 반응성을 떨어뜨린다. 흡연에 대한 부호 숫자 짝짓기(순간 판단력)을 검사한 결과, 니코틴의 수면에 대한 상호관계는 알려지지 않았고, 인간의 감정이나 의식, 인식에 영향을 주는 것으로 알고있지만, 장기적은 측면에서 흡연이나 알코올은 인식능력과 무관한 것 같다. 카페인에 대한 숫자 외우기(암기력)검사 결과, 카페인은 spacial selective attention에는 특별한 영향을 주지 않지만 지각과정이나 주의 집중에 큰 효과를 주며, 인간의 의식 수행에 긍정적인 효과를 준다. 즉 카페인은 활력, 혼란, 피로상태를 변화시키고 visual analog scales에서 휴식상태에 가까운 양상을 나타낸다. 또 48시간 동안 수면을 취하지 않은 사람에게 카페인은 집중력과 장시간의 좋은 기분을 유지하게 하였다. 그러나 규칙적, 비규칙적으로 먹는 사람간에는 인지수행력의 차이를 보이지 않으며 상용자에서는 상당한 내성이 보인다. 수면패턴에 대한 숫자 더하기(순간 판단력)검사 결과, 집중력은 수면패턴에 의해서도 영향을 받고, 수면패턴이 바뀌게 되면 순간판단력을 저하시킨다. This study was performed to evaluate relationship of sleep and attention, and to control sleep effectively. We conducted a K-PES test of 40 medical students. K-PES contains eight elements, for example, simple response, selective response, color pairing, OddEven discrimination, number addition, number-symbol matching, memory, right-tapping, left tapping. Through these, we tested changes of memory, judgement, simple response. And we conducted a questionnaire survey to exclude bias. Results are as follows. As a results of number-symbol matching test, we know that sleeplessness is not complete responsible for physiologic function for humans. But, decreased sleep increases fatigue and decreases motivation, but no influence on learning new materials. So, long term sleeplessness decreases precision and responsibility. As a results of number-symbol matching test on smoking, a relationship of nicotine and sleep is not certain. A point of view in long term period, smoking and drinking is not related cognition, even if we know that those influence mood, consciousness and cognition. As a results of memory work test on caffeine, caffeine does not influence spacial selective attention, but mainly does perception, attention and consiousness process. Namely caffeine changes energetic activities, chaos, fatigue states and shows resting state in visual analog scales In sleeplessness for 48 hours, caffeine produced attention and good mood for a long time. But, in case of cognitive process no significance shows in regular or irregular diet. Regular diet shows high resistance. As a results of number addition test on sleep patterns, seep patterns influence attention, changes of sleep patterns decrease a moment judgement.

생체분해성 망막압정을 이용한 망막고정에 대한 실험적 연구

김용백,민병무,김창식,박근성,김승영,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

Biodegradable retinal fixation devices obtain mechnical fixation of the retina with desirable chorioretinal scarring and with the potential for local, sustained release of antimetabolites and steroids to inhibit proliferative vitreoretinopathy. We manufactured a biodegradable retinal tack with barb that was designed in order to prevent intrusion from implantation of retinal tacks. This study was carried to evaluate the efficacy for retinal fixation and the capability for sustained release of drugs with a newly designed biodegradable retinal tack Biodegradable retinal tacks were made of polymers of glycolic acids and were designed with barbs in a shape to prevent the disinsertion. Biodegradale retinal tacks are divided into 3 parts, a conical portion that is inserted into the sclera, a cylinder portion that remains in the vitreous, and a neck portion between the pin and the cylinder. The tapered conical end was manufactured to allow easy insertion through the retina and choroid into the sclera. A cylinder portion was manufactured with a tapered angle that fixes firmly into the orifice of 19 gauge spinal needle. A neck portion, 0.4 mm in diameter, was designed to prevent disinsertion from following implantation of retinal tack. The applicator was a 19 gauge spinal needle and its orifice was prepared to 15°angle to accept the tapered cylinder portion of the retinal tack. The retinal tacks, secured in the needles, were passed through the formed vitreous and inserted into the retina, choroid, and sclera and were released by pushing the internal needle, usually within 2-3mm of the medullary ray of the posterior rabbit retina A retinal tack was placed in each of 8 pigmented rabbit eyes. Slit-lamp biomicroscopy, indirect ophthalmoscopy and fundus photography were performed periodically from 1 day to 8 weeks after surgery. Eight eyes were enucleated and studied by light microscopy at 8 weeks. Biomicroscopic evaluation of the animals revealed edemas adjacent to the retinal surfaces immediately after insertion of the biodegradable retinal tacks in all the animals. These edemas disappeared after 1 week. The first noticeable change in the size of retinal tacks was shown after 2weeks. The size of the retinal tacks gradually got smaller, decreasing to about one-half at 4 weeks and about one-third at 8 weeks. All retinal tacks remained in inserted places without any movement for an 8 week period. On light microscopy, epiretinal proliferations were seen to extend into the vitreous cavity. Cellular capsules that lined the inner aspect of the scleral defect caused by tack insertion were found. However the adjacent retina had a normal cytologic appearance and architecture in all specimens. We manufactured a biodegradable retinal tack that is designed to prevent intrusion from implantation of retinal tacks. All biodegradable retinal tacks reduce in size with time, but no retinal tacks extruded from the inserted place. The newly designed biodegradable retinal tack can be used for retinal fixation and may be used as a vehicle for the introduction of pharmacologic agents to prevent the cellular events that promote proliferative vitreoretinopathy.

베타-글루쿠로니다제에 의한 황련ㆍ황금 공침물의 가수분해 및 생체이용률 증가

김미정,김남순,김영일,김대근,양재헌 한국약제학회 2003 Journal of Pharmaceutical Investigation Vol.33 No.2

During the preparation of decoction from the mixture of Coptidis Rhizoma and Scutellariae Radix, insoluble copreciptate was formed. The coprecipitated product(COP) was composed of berberine and baicalin which was the active ingredient of Coptidis Rhizoma and Scutellariae Radix, respectively. COP was slightly soluble in water and could not be well absorbed after oral administration. This poor bioavailibility might be associated with its poor aqueous solubility. With the purpose of increasing the solubility and bioavailibility of COP, hydrolysis of COP by β-glucuronidase was carried out. Hydrolyzed products (HOP) of COP were identified and assayed for active ingredients. The partition coefficient study, in situ absorption test, and pharmacokinetic study after oral administration were also performed. COP was found to be consisted of berberine and baicalin with molecular ratio or 1 to 1. This compound was hydrolyzed to berberine and baicalin by β-glucuronidase. The rate of hydrolysis was higher at higher temperature up to 50℃ and higher concentration of β-glucuronidase up to 2500 unit under our experimental conditions. Baicalein, which is more liphophilic than baicalin, showed greater absorption in small intestine than baicalin did. The plasma concentrations of berberine and baicalein after oral administration of HOP were significantly higher than those of COP. The possible mechanism of increased bioavailibility of berberine and baicalein could be the hydrolysis of COP by β-glucuronidase. On the basis of the above results, it might be said that HOP should be a suitable preparation for increasing the bioavailibility of Coptidis Rhizoma and Scutellariae Radix.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

대청댐 유역 비점오염 저감방안 수립을 위한 연구

이대근 ( Dae Keun Lee ),김장현 ( Jang Hyun Kim ),전양근 ( Yang Kun Chun ) 한국물환경학회 2004 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2004 No.-

구두발표 : 비점오염원관리 (2) ; 대청댐 유역 비점오염 저감방안 수립을 위한 연구

이대근 ( Dae Keun Lee ),김장현 ( Jang Hyun Kim ),전양근 ( Yang Kun Chun ) 대한상하수도학회 2004 공동춘계 학술발표회 논문집 Vol.2004 No.-

생체분해성 고분자를 이용한 사시수술용 제형개발 및 효용성에 대한 연구

민병무,김용백,김승영,김창식,박근성,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

A new device, muscle clamping system was developed to facilitate exact quatifying technique A strabismus surgery, and reduce the risk of complications. The device is composed of a lower fixing body with three jaws and an upper supporting body. They are used to clip an extraocular muscle and fix it to the sclera with a single bite. Superior rectus recession on 16 rabbit eyes were performed with this new device. Conjunctival injection, muscle adhesion strength, and light microscopic findings were examined at 1, 2, 4 and 8 weeks postoperatively. The Conjunctival injection were minimal, adhesion power ranged from 420 to 600 gram gravity, which is sufficient in withstand the normal pull of human extraocular muscle. In microscopic exam, some Inflammatory cells and fibrosis were found. The new device was technically easy, fast, and accurate, so it may be useful in stabismus surgery.

8년간(1992~1999) 산업안전보건연구원에 의뢰된 직업병 심의 사례 분석

강성규,김규상,김양호,최정근,안연순,진영우,최병순,양정선,김은아,채창호,최용휴,김대성,박정선,정호근 대한산업의학회 2000 대한직업환경의학회지 Vol.12 No.2

Objectives : Pneumoconisis and noise-induced hearing loss (NIHL) have been reported as main occupational diseases by the Special Health Examination. The Industrial Accident Compensation Insurance has reported various work-related diseases, however, these two diseases occupied almost a half of compensated cases. Therefore, it was not well known about the status of occupational diseases other than pneumoconiosis, NIHL, and cardio-cerebrovascular accident (CVA). This study was conducted to analyze claimed cases as an occupational disease, that was requested to the Korea Industrial Safety and Health Agency (KOSHA). Methods : The local office of the Korea Labor Welfare Corporation (KLWC) has asked the KOSHA for confirmation of claimed cases as an occupational disease. We analyzed 379 cases requested from KLWC, the Ministry of Labor, employers, unions and occupational health agencies from 1992 to 1999. Results : Male was 80.7 % of the requested cases. Their mean age was 42 years old and 75.5 % of them were more than 35 years old. The requested cases were increased rapidly from 25 cases in 1992 to 108 cases in 1999 and the accept rate was 50.7 %. The majority of requested cases were respiratory diseases(22.4%), cancers(18.5%), Neuropsychiatric problems(14.5%), and musculoskeletal problems(13.5%). The accept rate was high in reproductive, respiratory, musculoskeletal and digestive disorders and low in neuropsychiatric, renal and otologic problems and occupational cancers. 73.6% of them were caused by chemical agents, especially 28.5 % were by organic solvents. 67% of them were clinically confirmed at university hospitals. A half of the cases were from KyongIn area, even the request came from the whole country. Conclusions : A claim was common in workers whose age was over 35 years old and exposure history was over 10 years. The respiratory diseases and neuropsychiatric disorders were still main problems in occupational health and occupational cancers was increasing even though its accept rate was not high yet.

백서의 복강내에 투여한 Mitomycin-C-Polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

송규상,강대영,최정목,노승무,정경수,오정연,김진향,양준목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

To evaluate the in-vivo effects of mitomycin-C-polyglycolic acid composite(MMC-PGA) the disk: shaped composite were implanted into the peritoneal cavity of the Sprague-Dawley rats. The pathologic changes were examined at various time points up to 12 weeks. Initially the soft tissue around the inserted disks showed capillary congestion at 3 days. Inflammatory infiltrates with foreign body giant cells appeared from the 2nd week and reached peak response at 6-8 weeks. These reaction diminished prominently at 12 weeks. No specific pathologic change was found in the liver, the kidneys, and the heart. The above results suggest that the MMC-PGA composite can serve as a new device for intraperitoneal chemotherapy of various types of cancers.