TEOS 솔 침전공정에서 SiO2 과포화 농도 및 입자 크기에 미치는 반응조건 영향

김경수,김선근,김우식,김성수,김준경 한국화학공학회 2000 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.38 No.6

본 연구에서는 솔 침전공정에서 TEOS(Tetraethylorthosilicate) 반응물을 이용하여 실리카 분말 합성시에 TEOS 농도, 물농도, 반응물 주입속도, 교반속도 등의 반응조건이 실리카 과포화 농도 및 입자크기에 미치는 영향에 대해 연구하였다. TEOS 반응물과 물 농도가 증가할수록 입자유도시간은 짧아졌으며 입자유도시점에서의 과포화 농도는 감소하였다. 그러나, 반응물 주입속도가 입자유도시간과 입자유도시점에서의 과포화 농도에 미치는 영향은 서로 상반되었다. 즉, 반응물 주입속도의 증가에 따라 입자유도시간은 감소하였으나 입자유도시점에서의 과포화 농도는 증가하였다. 반응조건에 따라 서로 다른 과포화 농도에서 입자가 유도되는 것은 입자의 형성에 있어서 과포화도 이외의 용액의 조건에도 영향을 준다는 것을 의미하는 것이다. 한편, 교반속도는 입자유도시간과 유도시점에서의 과포화 농도는 거의 영향을 주지 않았다. 이것은 솔 침전공정에서 반응물 혼합시간이 충분히 짧아 실리카 생성에 있어서 반응속도가 입자유도 및 과포화 농도 결정에 가장 크게 영향을 미쳤기 때문이다. 반응조건에 따른 가수분해 및 축합 반응속도를 Kim등[15]이 제시한 식을 이용하여 예측하였으며 이 결과는 본 실험에서 측정한 입자유도시간의 함수로도 매우 잘 묘사될 수 있었다. 또한, 반응조건에 따라 합성된 최종입자의 크기 변화도 입자유도시간의 함수로 훌륭히 묘사될 수 있음을 보여 주었다. In a single feed semi batch reactor effects of reaction conditions, such as TEOS and water concentrations, react feed flow rate and agitation speed, on the silica supersaturation and particle size synthesized in sol precipitation were investigated. As the TEOS and water concentrations increased, the particle induction time and the supersaturation at the particle induction point were reduced. However, the dependencies of the particle induction time and supersaturation at the particle induction point on the reactant flow rate were opposite to each other. That was, the particle induction tune decreased with increase in the reactant flow rate but the supersaturation at the particle induction point increased. The fact that the supersaturation level to induce the particle was varied with the reaction condition implied that the solution condition determined by the reaction condition as well as the supersaturation level was important to the particle induction. Meanwhile, the particle induction time and supersaturation at the particle induction point were little influenced by the agitation speed in the reactor. This result was due to the micromixing time being short enough in comparison to the reaction time of TEOS. Thus, the particle induction time and supersaturation at the particle induction point was predominantly determined by the reaction time rather than the micromixing time of TEOS. The reaction rate constants of TEOS hydroysis and condensation, which was predicted with Kim et al.'s equations [15] at the reaction conditions was described as a function of the particle induction time. In addition, the particle size synthesized at the reaction conditions was able to be well fitted as a function of the particle induction time.

부산지역 수돗물과 지하수의 중금속 농도

김준연,손지언,김형수,김두희,원미숙,김인식,이혜령 동아대학교 산업의학연구소 2000 산업의학연구소 논총 Vol.- No.5

This study investigated mean airborne CO concention of 15 workplaces, suspected of CO exposure and conducted self-reported questionnaire completion and indirect COHb concentration measure using Micro II Smokerlyzer to healthy 702 adult subjects from 1999 May to 1999 September in order to find a relation of CO exposure and occupational factors, socioeconomic factors, and health related behaviors and confirm the related conditions in the screening test for CO exposure. The results of this study were summarized as follows : 1. In the CO exposed and non exposed group, COHb concentrations of the smokers were 2.55±0.96% and 2.21±0.97% and that got a statistically significant difference, There were not statistically significant differences in the age and total smoking index. Passed times after the last smoking, Working time/day, and working duration were statistically significant difference (p〈0.05). 2. In the CO exposed and non exposed group, COHb concentrations of non-smoking group were 0.94±0.35% and 0.68±0.47% and that got a statistically significant difference. There were not statistically significant differences in the age and working duration but Working time/day was a statistically significant difference(p〈0.05). 3. In the CO exposed group, r-square of multiple regression of the smokers was 38.5 % and passed time after the last smoking, working time/day, and job category were statistically significant differences (p〈0.05). And r-square in the CO non-exposed group was 38.3 % and age, passed time after the last smoking, and total smoking index were statistically significant difference. 4. In the CO exposed group, r-square of multiple repression of the non-smokers was 66.3% and job category and airborne CO concentration were statistically significant differences(p〈0.05). But r-square of non-smokers in the CO non-exposed group was 1.0% and there was not a statistically significant difference(p〈0.05). 5. In the smokers of CO exposed and non exposed groups, relation of COHb concentration and passed time after the last smoking was expressed as exponential function, Y = 2.9182e-0.0083x and r-square of this function was 37.4%. Therefore it was more than 150 minutes that passed time after the last smoking was when COHb concentrations were measured as less than 1%. In conclusion, variable, that was statistically significant to COHb concentraion in the both CO exposed and non-exposed smokers, was a passed time after the last smoking. We suggest that you have to restrict the smoking of smokers at least 150 minutes in the exposed and non exposed group before COHb concentration measure in order to exclude smoking effects

Effect of Developmental Lead Exposure on the Expression of Hippocampal NMDA Receptor Subunit mRNA

Kim, Tae-Wan,Chung, In-Sung,Bae, Jae-Hoon,Shin, Dong-Hoon,Lee, Mi-Young,Kim, Joon-Sik 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

목적: in vivo 및 vitro에서 해마 신경세포의 발생단계별 NMDA 수용체 아단위 mRNA 발현에 대한 연 폭로 영향을 알아보고자 하였다. 방법: 흰쥐 해마 신경세포의 발생단계별 NMDA 수용체 NR2A, NR2B 아단위 mRNA 발현에 대한 연의 영향은 정상군과 연 폭로군의 출생 후 7일, 14일, 22일 흰쥐의 해마에서 in situ hybridization으로 mRNA 발현 정도를 densitometer로 측정하여 비교하였고, 연과 NMDA 의 세포독성은 해마 신경세포 일차배양 후 도립현미경을 이용한 형태학적인 관찰과 LDH 활성도를 이용하여 측정하였다. 결과: 연 과 NMDA 에 의한 세포독성에 대한 in vitro 실험에서 형태학적 소견과 LDH 활성도에서 해마 미성숙 신경세포와 성숙 신경세포사이의 차이가 있었으므로, 연과 NMDA 독성효과는 해마 신경세포의 발달 단계에 따라 차이가 있다. 정상군의 해마에서의 NR2A mRNA 발현은 출생 후 연령이 증가함에 따라 점진적으로 증가하였으나, NR2B mRNA 발현은 출생 후 연령이 증가함에 따라 점진적으로 증가하였으나 NR2B mRNA 발현은 연령의 증가에 따른 변화가 없었다. 연 폭로에 희한 NR2A mRNA 발현은 유의하게 감소하였으나(p<0.05), NR2B mRNA 발현은 변화가 나타나지 않았다. 만성적 연 폭로는 NR2A를 포함하는 NMDA 수용체를 감소시킬 수 있음을 알 수 있다. 결론: 연은 해마신경세포의 발생단계에서 NMDA 수용체 아단위 특히 NR2A mRNA 발현의 변화를 야기하여 시냅스 신호 전달에 영향을 나타냄을 알 수 있었다. Hippocampus

독성물질의 세포사 기전 및 세포사 유발물질의 검색법 개발에 관한 연구(Ⅰ) : 독성물질로 인한 파킨슨병 모델에서의 세포사 기전 연구 Study on the cell-death mechanisms of toxin-induced parkinsonism

강태석,김종민,서경원,김영옥,김준규,오재호,이윤동,김규봉,오정자,송연정,임종준,전범석,문전옥,최광식 식품의약품안전청 2000 식품의약품안전청 연보 Vol.4 No.-

MPTP 독성물질이 도파민성 신경세포에 선택적으로 작용하여 산화성 손상에 의한 신경세포사를 일으키는 것을 이용하여 파킨슨병의 동물모델을 만들고, 이를 통해서 아폼토시스를 비롯한 포사의 기전에 대한 연구 및 너코틴의 신경세포 보호효과 여부를 판정하는 실험을 병행하고자 하였다. 파킨슨꾐의 동물모델을 MPTf 독성 물질을 이용하여 확립하였으며, MPTP(30mgag, i.p.)를 투여한 후 1, 2,3, 4, 5일째 흑질 조직을 채춰하여 tarm로 박걸하여 tyrosine hydroxylase 면역조직화학염색을 수행하여 cell countif우한 결과, control은 57.635ce11s, 1일째 친.OfDells,2일째 57.9±6cells,3일릴 없.3±죠ells, 4일째 49.0츠3cells, 5일째 39.4±Scells료 4, 3일째 뚜렷한 신경세포 수의 감소를 보였다. 신경세포사 기전 규명을 위한 아폼토시스 분걱에서는 벼PTP 투여 후 1, 2, 3, 4, 5일째 조직을 채취하여 Hoechst staining, TUNEL staining을 수곡하였는데 양성 반응을 보인 신경세포는 관찰되지 않아. 아폼토시스로 인한 세포사가 관찰되지 않았다. bIPTP 파킨슨병 동물모델에서 nicotine 보호효과 탐색에 관한 실험은 nicat푸e 0.2mgAg을 5일 퐁안 투여 후 리『fP(30mgag)를 CS7Bt/6 마은스에 복강 내주사로 nicotine과 병용 투여한 후 1, 2, 3, 4, 5일째 뇌를 적출하땄다. 신경세포사가 뚜렷이 관찰되기 시작하는 4, 5일째의 신경세포 수의 감소 정도를 20. 30% 정도 약화시키는 경향을 보였으나, nicotine 보호효과에 대한 추가 실헝이 현재 수행 중에 있다. The cause of Parkinson's disease (PD) is largely unknown. However, free radical toxicit? may plaf a role ip. the degeneration of substantia nigra, which is the Hajorfocus of pathological damages in PD. Recently, a neuroprotective effect of nicotine in PD has been suggested. Therefore, the mechanism of neurodegenerafion and protective potential o( nicotine in PD were investigated in the experimental modeB of Pll using a neurotoxin, C57BL/6mice were administered with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg,j.p.). The degree of neurodegenerafion was determined by immunohistochemical stainiHB oftyrosine hydroxylase (TH). TH-positive cells on nigral sections were found 56.0 ±4, 57.9 ±6,52.315ce11s, 49.0±3cells, and 39,4±Scells at days 1, 2, 3, 4, 5, respectively (controls : 57.6±Scells). Hoechst and TUNEL staining showed no evidence of apoptosis. The exandnation on themice co-adrunistered with nicotine(0.2mgAg) and MPTP(30mgag) revealed a tendency ofnicotine protective effects. At days 4 and 5, the degree of TH-positive cells was decreased by20-30%, In corclusiffn, the role of apoptosis was not evidenced in this MPTP modeB of PB.The possible proteccon by nicotine should be elucidated with further studies.

급성 백혈병 환자에서 수두양 피부병변을 보인 파종성 Fusarium 감염 1예와 국내 파종성 Fusarium 감염증에 대한 고찰

오수진,정희선,김준성,김태석,조병식,최수미,김명신,이연수,이석,신완식 대한감염학회 2007 감염과 화학요법 Vol.39 No.5

최근 면역저하환자의 증가와 함에 국내에서도 점차 침습성, 파종성 Fusarium 감염증 보고가 증가하고 있다. Fusarium 감염은 아스페르길루스 감염과 유사한 임상양상을 보이지만 특징적인 피부병변을 동반하고 혈액배양에서 균이 분리되는 경우가 더 많다. 저자들은 급성 림프구성 백혈병으로 진단받고 치료중인 30세 남자 환자에서 중증의 호중구 감소 상태에서 비특이적인 피부병변을 동반한 파종성 Fusarium 혈류감염을 경험하였기에 국내 증례 고찰과 함께 보고하는 바이다. 환자의 초기 피부병변은 구진에서 시작하여 주로 소포성 병변과 일부 통증을 동반한 결절 등 여러 형태로 나타났고, Tzank 도말검사 양성으로 비정형 수두로 오인되었다. 이후 피부병변은 농포로 변하였고, 혈액배양 및 피부 조직검사에서 파종성 Fusarium 감염으로 진단받았다. 환자는 liposomal amphotericin B, voriconazole 병합요법과 G-CSF 투여, 과립구 수혈을 받았으나, 호중구 감소증에서 회복하지 못하고 급성 호흡곤란증후군과 다장기 기능부전으로 사망하였다. 본 증례는 파종성 Fusarium 감염의 경우에도 수두양 병변으로 비특이적인 양상으로 나타날 수 있으므로, 감별진단을 위해 적극적으로 혈액배양과 피부조직검사를 시행해야 함을 보여준다. Recently, we experienced a case of disseminated fusarial blood stream infection with varicelloid skin eruptions, who had suffered from persistent neutropenic fever after salvage chemotherapy for relapsed acute lymphocytic leukemia (ALL). Neutropenia continued in spite of G-CSF and granulocyte transfusion, and he failed to respond to conventional amphotericin B initially, and then liposomal amphotericin B and voriconazole combination therapy. Disseminated fusariosis can be diagnosed by blood cultures in 50% of patients and present skin lesions in more than 80% of patients. So, typical skin lesions are important clue to diagnose of the disseminated fusariosis. However, many skin lesions in immunocompromised hosts are due to various infectious and non-infectious causes. So, this case shows that it is important to obtain biopsy specimens of skin lesions for histopathologic examination, culture and staining. Here, we present our case with the review of the literatures reported in our country, so far.

Rat의 복강에 삽입한 Fluorouracil-Polyglycolic acid 제형의 Fluorouracil 용출에 관한 연구

노승무,정경수,오정연,김진향,양준묵,강대영,송규상,최정목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 忠南大學校 癌共同硏究所 1998 癌共同硏究所 硏究誌 Vol.2 No.1

A common form of relapse in adenocarcinoma of the stomach is intraperitoneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adcnocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.

위암 환자의 복강내 투여를 위한 Activated Charcoal-Alginate Bead 제형으로부터 Mitomycin C의 용출 거동

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

Locoregional recurrence is the most common type of recurrence in surgical operation of gastric adenocarcinoma, and peritoneal dissemination is one of the most difficult problems in advanced gastric adenocarcinoma treatment. Because the peritoneal cavity is the most common site of the first recurrence after gastric cancer resection, intraperitoneal chemotherapy seems a logical choice for cancer chemotherapy. In this study, Mitomycin C (MMC)-activated charcoal (CH)-alginate (ALG) beads were prepared by the mixtures of CH particles adsorbed with MMC as an anti-cancer drug and aqueous alginate solution. The alginate is recognized as biodegradable, nontoxic, and biocompatible. The release of MMC from the beads in 0.1 M Tris buffer was stable and continuous until about 1 week. The MMC-CH-ALG beads can be applied in the peritoneal cavity for intraperitoneal chemotherapy since they provide a good adhesiveness on the tissue and controlled release pattern of the drugs.

Rat의 복강에 삽입한 Filorouracil-Polyglycolic acid제형의 Fluorouracil용출에 관한 연구

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

A common form of relapse in adenocarcinoma of the stomach is intraperitioneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adenocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.

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.

위암환자의 복강내에 투여한 Mitomycin C-Carbon Particle의 Mitomycin 용출에 관한 연구

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

Locoregional recurrence is the most common type of recurrence in surgical operation of gastric adenocarcinoma, and peritoneal dissemination is one of the most difficult problems in advanced gastric adenocarcinoma treatment. Because the peritoneal cavity is the most common site of the first recurrence after gastric cancer resection, intraperitoneal chemotherpy seems a logical choice for cancer chemotherapy. The Mitomycin C(MMC) adsorbed by the activated charcoal particles(CH) is relatively released when the drug concentration surrounding the carbon particles becomes low in the peritoneum of the peritoneal cavity. For the intraperitoneal chemotherapy on the advanced gastric adenocarcnoma, mitomycin C adsorbed on activated carbon particles was administered in the peritoneal cavity just before abdominal wall closure. The closed drainage tubes were inserted in the peritoneal cavity and clamped for tuo hours after completion of operation. MMC concentrations were serially measured in peritoneal fluid, plasma and urine at 2hour, 48 hour, 72 hour and 168 hour following its administration in order to study the efficacy of the MMC-CH as a drug delivery system. There were minimal toxicities in born marrow, liver, and gastrointestinal system after intraperitoneal MMC-CH administration. The data of this study suggested that MMC-CH may have a somewhat more beneficial effect than surgery alone when administered in optimal dose and schedules, but the MMC concentration of the peritoneal fluid was not sufficient to eradicate remnant cancer cells, and effective duration of maintenance was only below 24 hours in the peritoneal fluid and plasma.