• 한방재활의학과학회지
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• 제21권2호
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• pp.63-85
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• 2011

Objectives : This study was carried out to know the effects of Danggwisayeokgaohsuyusaenggang-tang(hereinafter referred to DST) on arthritis induced by collagen on DBA/1 OlaHsd mice. Methods : For this purpose, DST was orally administered to mouse with arthritis induced by collagen II. Cytotoxicity, high performance liquid chromatograph(HPLC) analysis, arthritis index, value of immunocyte in draining lymph node and paw joint, cytokine were measured in vivo. Results : 1. The cytotoxicity against human fibroblast cells(hFCs) was not measured in any concentration. 2. In HPLC analysis, There are high peak patterns at 8 minute(min), 12 min, 35 min, 45 min. 3. The arthritis index was decreased significantly. 4. The degree of arthritis induced damage of joint of DST group is slight compared with control group in histopathologic observation(Hematoxylin and eosin stain(H&E), Masson's trichrome(M-T) staining). 5. In total cell counts of draining lymph node(DLN) and paw joint, the cells in DLN decreased significantly on DST 200 mg/kg and the cells in paw joint decreased significantly on 200 mg/kg and 50 mg/kg. 6. In DLN, $CD4^+/CD25^+$, $CD3^+/CD69^+$, major histocompatibility complex(MHC), class-II/$CD11c^+$ cells decreased significantly on DST 200 mg/kg and 50 mg/kg $CD3^+/CD8^+$ cells decreased significantly on DST 200 200 mg/kg, $CD4^+$, $CD3^+/CD44^+$ cells decreased. 7. In paw joints, $CD4^+$, $CD11b^+/Gr-1^+$ cells decreased significantly on DST 200 mg/kg and 50 mg/kg. 8. In joints, levels of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, cyclo-oxygenase-2(COX-2), NOS-II were decreased on DST 200 mg/kg and DST 50 mg/kg. 9. In analysing of cytokine in CD3/CD28 activated spleen, IL-17 was decreased significantly, IL-4 was increased significantly $INF-{\gamma}$ was decreased on DST 200 mg/kg. 10. In analysing of cytokine in collagen activated spleen, IL-17 were decreased significantly, IL-4 was increased significantly. Conclusions : This results demonstrated that DST suppressed the inflammatory progression of collagen-induced arthritis(CIA) mice and supported further studies are required to survey continuously in looking for the effective substance and mechanism in the future.

• 동의생리병리학회지
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• 제21권6호
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• pp.1549-1554
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• 2007

To verify the effects of JAUN-1, which is a water-extracted herbal mixture, on gastroenteric disorders induced by 0.1 percent of iodoacetamide (IA) in rats. We divided four groups, $Na{\"{\i}}ve$ + Distilled Water (DW), 0.1% IA + DW, 0.1% IA + Proton pump inhibitor (Lansoprazole, 5 mg/kg) and 0.1% IA + Herbal mixture (JAUN-1, 50mg/kg) and performed following experimental methods to confirm its advantageous effects against ulcerogenic stomach in rats induced by 0.1% IA; cell cytotoxicity, analysis of lesions score, Hematoxylin & Eosin (H&E) stain, RT-PCR for ${\beta}-actin$, COX-1 and COX-2 and evaluation of intestinal prokinetic activity. No cytotoxicity was elucidated at the concentration of 1, 5, 10, 50, 100, $500\;{\mu}g/ml$ and 1mg/ml JAUN-1 through MTT Assay using by human stomach epithelial AGS cells, respectively. In addition, the JAUN-1 treated group and the lansoprazole treated group significantly decreased in lesions score compared to the DW treated group in the gastritis induced rat model, and results of immunohistochemistry by H&E staining showed that histological recovery in Proton Pump Inhibitor (PPI) and JAUN-1 treated groups rather than the DW administrated group. Another outcome was that ${\beta}-actin$ relative COX-2 expression level was significantly promoted in the DW treated group while ${\beta}-actin$ relative COX-1 expression level was no meaningful change in this rat model. Finally, intestinal prokinetic activity was recovered from low level of prokinetic activity due to 0.1% IA induced gastritis to the similar level of Normal group. These results suggested that JAUN-1 may have beneficial effects against 0.1% IA-induced gastritis rat model through decreasing lesions score, histological recovery, ${\beta}-actin$ relative COX-1, 2 expression level and prokinetic activity.

• Clinical and Experimental Reproductive Medicine
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• 제28권3호
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• pp.183-190
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• 2001

Objective: Recently, microdissection of tissue sections has been used increasingly for the isolation of morphologically identified homogeneous cell populations, thus overcoming the obstacle of tissue complexity for the analysis cell-specific expression of macromolecules. The aim of the present study was to establish the minimal conditions required for the RNA extraction and amplification from the cells captured by the laser captured microdissection. Methods : Mouse ovaries were fixed and cut into serial sections (7 im thickness). Oocytes were captured by laser captured microdissection (LCM) method by using PixCell $II^{TM}$ system. The frozen sections were fixed in 70% ethanol and stained with hematoxylin and eosin, while the paraffin sections were stained with Multiple stain. Sections were dehydrated in graded alcohols followed by xylene and air-dried for 20 min prior to LCM. All reactions were performed in ribonuclease free solutions to prevent RNA degradation. After LCM, total RNA extraction from the captured oocytes was performed using the guanidinium isothiocyanate (GITC) solution, and subsequently evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) for glyceraldehyde-3-phosphate-dehydrogenase (GAPDH). Results: With the frozen sections, detection of the GAPDH mRNA expression in the number of captured 25 oocytes were not repeatable, but the expression was always detectable from 50 oocytes. With 25 oocytes, at least 27 PCR cycles were required, whereas with 50 oocytes, 21 cycles were enough to detect GA PDH expression. Amount of the primary cDNA required for RT-PCR was reduced down to at least 0.25 $\grave{i}$ l with 50 oocytes, thus the resting 19.75 il cDNA can be used for the testing other interested gene expression. Tissue-to-slide, tissue-to-tissue forces were very high in the paraffin sections, thus the greater number of cell procurement was required than the frozen sections. Conclusion: We have described a method for analyzing gene expression at the RNA level with the homogeneously microdissected cells from the small amount of tissues with complexity. We found that LCM coupled with RT-PCR could detect housekeeping gene expression in 50 oocytes captured. This technique can be easily applied for the study of gene expression with the small amount of tissues.

• Journal of Periodontal and Implant Science
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• 제38권1호
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• pp.59-66
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• 2008

Purpose: It has been shown that the inorganic polyphosphate is effective for the regeneration of bones through the preliminary animal test of rabbits. The most effective concentration of the polyphosphate, however, is not known yet. Moreover, the effectiveness of carriers inside human body is not confirmed.. Materials and Methods: In this study, we examined the effect of the concentration of the inorganic polyphosphate on the process of the bone regeneration using the 6 weeks old rabbits with the weight of 2.0 kg in average. We performed the experiment using TR-ePTFE membrane(membrane) filled with collagen immersed in 4%, 8% of inorganic polyphosphate, respectively, following removal of the proper sized cortical bones from the rabbit calvaria. The experimental results were compared with the one of the following four groups: The negative control group for membrane only, the positive control group for membrane filled with collagen, the first experimental group for membrane filled with collagen immersed in 4% of inorganic polyphosphate, and the second experimental group for membrane filled with collagen immerse in 8% of inorganic polyphosphate. The fragments of the tissue with membrane obtained from each group of the sacrificed rabbits for 8 or 16 weeks sustained after surgery were then prestained by the Hematoxylin-Eosin stain and coated by resin to form non-decalcified specimens for the histologic examination and analysis. New bone formation was assessed by histomorphometric and statistical analysis. Results: 1. All groups have shown better bone regeneration at 16weeks than 8weeks. 2. Negative control group has shown more bone regeneration relative to the other groups at 8 and 16 weeks. 3. All experimental groups have shown better bone regeneration relative to positive control group. 4. At 16 weeks, the first experimental group has shown more bone regeneration compared to the second experimental group. Exophytic bone formation is not good at the first and the second experimental groups compared with negative control group. But, the use of 4% inorganic polyphosphate was more effective to bone formation than the use of 8% inorganic polyphosphate. Conclusion: With above results, it is suggested the use of inorganic polyphosphate with vehicle under TR-ePTFE membrane.

• 한국어병학회지
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• 제9권2호
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• pp.147-155
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• 1996

수온과 pH가 높은 조건에서 뱀장어에 미치는 암모니아 급성독성에 대하여 육안적인 면과 병리조직학적 변성을 관찰하였다. 육안 관찰 결과, 암모니아 무첨가구(0 mg/$\ell$)에서는 pH 8.5이상에서 아가미의 암갈색화가 진행되었고 암모니아 20 mg/$\ell$ 이상의 농도에서는 pH 7.5에서도 위와 같은 증상이 나타났다. pH 9.0에서는 암모니아 10 mg/$\ell$이상의 농도에서 1시간 이내에 전부 폐사했다. 아가미에 대한 조직학적 관찰 결과는 암모니아 무첨가구의 pH 7.5에서만 정상 조직이 관찰되었고 수온과 pH의 상승, 암모니아 농도의 증가 및 노출시간의 경과에 따라 조직의 변성이 심해지는 경향을 보였다. 암모니아 무첨가구의 pH 8.0, 8.5에서도 2차새변의 부종과 만곡증상이 보였고 pH 9.0에서는 2차새변 상피의 박리증상이 나타난 것으로 보아 높은 pH 조건만으로도 병변을 일으키는 요인이 될 수 있는 것으로 사료된다. 조직학적 변성의 초기에는 2차새변의 부종과 만곡증상이 보이다가 상피세포의 박리와 괴사로 진행 되었으며, 특히 2차새변상피의 박리증상은 육안적으로 관찰되는 아가미의 암갈색으로 변색시점과 비슷한 시기에 관찰되었다. 암모니아 20 mg/$\ell$이상에서는 pH 8.5, 수온 $27^{\circ}C$ 조건에서 2차새변상피의 괴사가 일어났고, 수온 $32^{\circ}C$에서는 노출시간이 경과하면서 폐사체가 생겼다.

• Parasites, Hosts and Diseases
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• 제27권2호
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• pp.101-108
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• 1989

실험 동물의 면역기능을 인위적으로 억제시킴과 동시에 몇 가지 항생 물질을 투여하여 Pneumocystis carin힐 또는 다른 원인에 의한 폐염을 발현시킨 다음 각 원인별 치사율 및 평균 생 존 기간(mean survival day) 등을 비교함으로써 간질성 폐염의 원인충으로서 흑 carinil히 중요성 을 알아보고자 이 연구를 실시하였다. 실험 동물로 Sprague-Dawley계 흰쥐 90마리를 사용하였고 각각 15마리씩 1개 대조군과 다음 5개 투약군으로 분류하였다. 1군 prednisolone(25mg/kg twice weekly), 2군 prednisolone과 tetracycline (75mg/kg/day) , 3군 prednisolone, tetracycline 및 trimethoprim·sulfamethoBazole (50∼250mg/kg/day), 4군 prednisolone과 trimethoprim-sulfamethozazole, 5군 prednisolone과 griseofulvin(300 mg/kg/day). 상기 약제를 횐쥐가 죽을 때까지 투여하고 각 흰쥐의 생존 기간을 측정하였다. 죽은 흰쥐는 즉시 부검하여 폐장을 적출한 후 접촉 도말 표본과 조직 절편 표본을 만들고 toluidine blue O, Giemsa, Gomori's methenamine-silver, hematoxylin-eosin, Brown & Brenn 염색 등을 하여 관찰하였다. 각 군별 평균 생존 기간은 1군 $19.3{\pm}5.2$일, 2군 $41.1{\pm}14.0$일, 3군 $50.5{\pm}18.4$일, 4군 $43.0{\pm}22.9$일, 5군 $21.8{\pm}5.1$일이었다. 카 군별 생존 기간의 차이를 비교하면 1군과 2군, 1군과 3군 및 1 군과 4군이 각각 유의한 차이(p<0.01)를 보여 세균 감염 방지시 생존 기간이 연장되는 것으로 나타났다. 또 1군과 5군의 생존 기간은 거의 차이가 없었고, 2군과 5군, 3군과 5군 및 4군과 5군은 유의한 차이(p<0.01)를 보여 진균 감염보다는 세균이나 P. carinii 감염이 흰쥐 사인에 직접적인 영향을 주는 것으로 나타났다. P. carinii 폐염에 의한 사망은 실험 17일에 최초로 나타났으며 각 군별 비율은 3군이 92.9%로 가장 높고, 2군 및 5군이 80.0%, 4군이 78.6%, 1군이 33.3%를 보였다. P. carinii 폐염으로 죽은 53마리를 분류한 바 stage 1은 11.3%, stage 2는 28.3%, stage 3은 60.4%이었다. 죽은 흰쥐의 사인을 기간별로 분류했을 때 실험 전기(1일∼28일)는 세균 감염에 의한 사망이 많 고, 실험 중기(29∼56일)는 주로 P. carinii 폐염에 의한 사망이었으며 진균과의 혼합감염이 이 시 기에 나타났다. 실험 후기 (57∼82일)에는 세균, 진균 감염 없이 모두 P. carinii 폐염으로 사망하 였다. 이상의 결과로 볼 때 면역억제제 투여 1개월 이후 흰쥐의 사망 원인으로는 세균이나 진균성 폐염 보다 P. carinii 폐염이 더욱 중요하다는 것을 알 수 있었다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제5권1호
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• pp.19-25
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• 2002

목적: H. pylori에 대한 제균요법은 제균 효과와 안전성, 그리고 환자의 순응도와 경제성 등의 기준에 따라 약제를 선택하여 사용하고 있으며, 그 중 PPI제제가 포함된 삼제 병합요법은 성인에서 H. pylori 감염의 효과적인 치료법으로 인정되고 있다. 그러나, 소아에서 omeprazole, amoxicillin, clarithromycin (OAC) 삼제병합 요법의 H. pylori 제균 효과에 대해서는 아직 연구가 부족한 실정이다. 이에 저자들은 소아에서 OAC 삼제 병합요법을 1주 및 2주 투여군으로 나누어 그 제균 효과를 비교해 보고자 하였다. 방법: 1998년 7월부터 2000년 7월까지 연세의대 세브란스병원 소아과에 상부위장관 증세로 내원하여 위십이지장 내시경을 시행받고, 생검조직의 CLO검사와 H&E염색 또는 Alcian yellow 염색에서 H. pylori 감염으로 진단받은 후 omeprazole (0.7 mg/kg/day), amoxicillin (50 mg/kg/day), clarithromycin (25 mg/kg/day)을 투여한 34례를 1주 투여한 군과 2주 투여한 군으로 나누어서 H. pylori 제균 효과를 알아보았다. H. pylori 제균은 투약종료 4주 후에 내시경검사를 시행하여 얻은 생검조직의 CLO검사와 H&E 또는 Alcian yellow 염색에서 모두 음성인 경우로 정의하였다. 결과: 대상환아 34례 중 1주 투여한 군이 21명, 2주 투여한 군이 13명이었으며, 1주 투여한 군의 평균 연령은 $9.5{\pm}3.0$세, 남녀 비는 남자 11명, 여자 10명이었고, 2주 투여한 군의 평균 연령은 $9.9{\pm}4.0$세였고, 남녀 비는 남자 4명, 여자 9명이었으며, 내시경 진단은 결절성 위염이 19례(52.9%)로 가장 많았으며, 표재성 위염이 7례(20.6%), 소화성궤양이 4례(11.8%), 자반성 십이지장염이 2례 (5.9%)였고, 정상소견이 2례(5.9%)였다. 총 34례 중 28례(82.4%)에서 H. pylori가 제균되었는데, OAC를 1주 투여한 군에서는 21례 중 17례(81.0%), 2주 투여한 군에서는 13례 중 11례(84.6%)가 제균되었다. 제균되지 않은 6례에서는 colloidal bismuth subcitrate ($Denol^{(R)}$), metronidazole 등을 추가하여 치료하였으나 H. pylori는 제균되지 않았고, 그 후 추적 관찰되지 않았다. 결론: 본 연구에서 상부위장관 증세를 가진 H. pylori 감염 환아에 대한 omeprazole, amoxicillin, clarithromycin 삼제 병합 요법의 제균율은 82.4%로 성인에서의 85~95%와 유사하여, 일차치료로서 효과적인 것으로 사료된다. 또한 치료기간별 H. pylori 제균율은 1주 투여한 군에서 81.0%, 2주 투여한 군에서 84.6%로 두 군 간에 의미 있는 차이는 없었다(P=0.785).

• 한국식품과학회지
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• 제40권4호
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• pp.436-442
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• 2008

본 연구를 통하여 피부 미용 소재로 알려져 있는 콜라겐 펩타이드를 섭취한 후 혈중에 나타나는 소화분해산물 중 콜라겐 특유의 아미노산인 hydroxyproline과 이것의 dipeptide 형태인 Pro-Hyp이 피부에 미치는 영향을 알아보고자 하였다. 피부 미용 소재를 경구 섭취하는 사람의 피부는 광노화 및 자연노화가 어느 정도 진행된 상태이므로, 이와 유사한 조건을 조성하기 위해 경구 투여를 시작하기 전에 hairless mouse에 7주간 주 3회 UV를 조사하여 주름을 선유발시켰다. 군 분리를 시킨 후 7주간 경구로 실험물질을 주 5회 반복 투여하면서, 주 3회 UV 조사를 병행하였으며, 시험 기간 중 임상증상, 체중변화를 관찰하였고, 3회 (0,4. 7주차) 피부주형을 채취하여 영상 분석을 실시하였으며, 2회 (0,7 주차)의 피부탄력측정 및 1회(7주차)의 TEWL측정을 병행하였다. 실험종료 후 피부조직의 병리조직학적 검사(H&E, Masson-Trichrome stain) 및 피부두께 측정을 실시하였다. 실험기간 중 이상 임상증상을 보이거나 사망한 개체는 없었으며, 체중에 대한 통계적으로 유의한 변화는 관찰할 수 없었다. 피부 육안관찰 시 NC군에 비해 UC군의 피부 주름 증가가 뚜렷하였으며, 시험군들은 UC군에 비해 주름 증가가 적었다. 경구 투여 0, 4, 7주차에 제작된 replica의 주름 지표를 통계 처리한 결과, UV/H군과 UV/P군은 DC군에 비해 감소경향은 보였으나 유의적인 차이는 없었다. 탄력측정검사 결과 UV를 쬐지 않은 NC군은 UC군에 비해 UA/UF, Ur/Ue, Ur/Uf 지표에서 유의적인 증가를 보였다. UV/H군과 UV/P군은 모두 0, 7주차 모두 유의적인 차이를 보이지 않았다. 피부 보습력 측정 결과 NC군 및 모든 실험군에서 UC군에 비해 유의적인 TEWL 감소를 관찰할 수 있었다. 피부 두께의 경우 NC군, UV/H군, UV/P군은 UC군에 비해 피부 두께가 유의적으로 감소하였다. 진피층에서의 교원질 확인을 위해 실시한 Masson-Trichrome stain의 경우 UC군에서는 상부 진피층에서의 염색상 소실이 관찰되었으나, 모든 실험군에서 진피층 손상이 거의 관찰되지 않아 실험물질에 의한 회복을 확인 할 수 있었다. 이상의 실험 결과 hydroxyproline, Pro-Hyp의 경구반복투여시 자외선에 의해 광노화가 유발된 피부에 보습 효과, 피부 두께 감소 효과, 진피층 손상 회복 효과를 유의적으로 확인할 수 있었으며, 단, 피부 주름 개선 정도는 통계적 유의성은 없이 경향성만을 확인할 수 있었다. Hydroxyproline과 이를 함유하는 dipeptide 형태의 Pro-Hyp를 경구 투여한 시험으로부터 확인한 피부 보습 및 진피층 회복 효과는 이 물질들이 유래된 콜라겐을 도포 또는 섭취했을 때 피부에 나타날 수 있는 작용들과 상통하며, 단독 미용 소재로도 활용될 수 있는 가능성을 보여주었다. 본 연구에서는 콜라겐 펩타이드를 섭취 시 체내에 흡수되어 혈액을 통해 각 조직에 운반되는 분해 산물이 피부에 미치는 영향을 동물 시험을 통해 살펴보았는데, 향후 연구에서는 관절, 혈관과 같은 다른 생체 조직들에 미치는 영향에 대해서도 검증해 볼 필요가 있다.

• Radiation Oncology Journal
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• 제12권3호
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• pp.271-284
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• 1994

Purpose : Phospholipase C(PLC) isozymes play significant roles in transmembrane signal transduction. PLC-${\gamma}1$ acts as the intracellular effector in signal transduction for cellular proliferation and differentiation. Ras oncoprotein is also involved in cell growth. We determined the biological significance of PLC and ras oncoprotein in regeneration following radiation and the effect of different modes of administration of 5-FU. Materials and Methods : To determine the effect of the administration mode of 5-FU on the regeneration of intestinal mucosa of rats following radiation, we compared the expression of PLC and ras oncoprotein in six groups. Group I had no treatment. Group II received radiation(8 Gy) only. Group III received radiation(8 Gy) and 5-FU(150mg/kg) continuous intravenous (iv) infusion for 12 hours. Group IV received radiation(8 Gy) and 5-FU(750mg/kg) iv bolus injection. Group V received only 5-FU(150mg/kg) continuous iv infusion for 12 hours, Group VI received only 5-FU (150mg/kg) iv bolus injection. Through immunoblotting and immunohistochemistry, we examined the expression of PLC and ras oncoprotein in rat jejunum at 96 hours after radiation or 5-FU administration and at 120 hours after radiation and 5-FU adminstration. We also investigated the histological findings using hematoxylin and eosin stain. Results : In the immunohistochemistry study, PLC-${\gamma}1$ expression was the highest in group III followed by groups II and VI in that order and was weakly positive in groups V and VI. PLC-${\gamma}1$ was hardly detected in the control group. The expression of ras oncoprotein was the same as the PLC-${\gamma}1$ expression for all groups. These results were confirmed by the histological findings regarding the mucosal regeneration. In the immunoblotting analysis, PLC-${\gamma}1$ expression was the highest in group III followed by group IV and II in that order. This difference between the immunoblotting and immunohistochemistry study was due to the high expression of PLC-${\gamma}1$ on the damaged surface epithelium rather than to its expression in the regeneration region as observed in the immunohistochemistry study for group IV. The expression of PLC-${\delta}1$ was positive only in group V and VI, which received both radiation and 5-FU, and the expression of PLC-${\beta}1$ was negligible for all groups. Conclusion : These results suggest that PLC-${\gamma}1$ mediated signal transduetion and ras oncoprotein may have a significant role in mucosal regeneration after radiation, and that continuous iv infusion of 5-FU may induce active regeneration in intestinal mucosa following radiation. In addition, the expression of PLC-${\delta}1$ in combined group of radiation and 5-FU implies that PLC-${\delta}1$ may be involved in signal transduction mediated by concerted action between radiation and 5-FU.

• Journal of Periodontal and Implant Science
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• 제26권4호
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• pp.989-1002
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• 1996

The purpose of this study was to determine the effect of a pulsed Nd:YAG laser irradiation on human gingival tissues. The patients, who were planned to be treated by clinical crown lengthening procedure and gingivectomy, were selected. All the patients received oral hygiene instruction, scaling and root planing at preoperation. The crest of gingival tissue on upper and lower anterior teeth was irradiated by a pulsed Nd:YAG laser(El. EN. EN060, Italy) with a fiber optic of 300 m in contact mode for 20 seconds. Gingival tissues were divided into 4 groups according to the laser power of 1.0W(10Hz, 100mJ), 2.0W(20Hz, 100mJ), 3.0W(30Hz, 100mJ) and 4.0W(40Hz, 100mJ). Immediately after the laser irradiation, the specimens were excised, fixed 10% neutral formalin, sectioned $4-6{\mu}m$ thick, stained by Hematoxylin-Eosin and Periodic Acid Schiff stain and observed under light microscope. The removed tissue depth and the coagulated layer depth due to a laser irradiation by a laser irradiation were measured on the microphotographs. The difference of measurements according to the different laser power was statistical1y analyzed by Kruskal Wallis Test with SAS program. The results were as follows : 1. In histologic findings of irradiated gingival tissues; a. In the irradiated gingival specimen with 1.0W laser power, some vesicles were observed in limited superficial layer of gingival epithelium. b. In the irradiated gingival specimen with 2.0W and 3.0W laser power, the epithelium was almost removed except for the traces of viable basal cell remnants at ret peg, and coagulation necrosis related with the thermal effect of laser was noted. c. In the irradiated gingival specimen with 4.0W laser power, complete removal of epithelium, partial removal of underlying connective tissue, and the coagulation necrosis of subjacent gingival tissue were shown. 2. The removed tissue depth was deeper in the irradiated specimens with higher power. There was a statistical significance in the difference of removed tissue depth between 1.0W group ($44.54{\pm}6.99um$) and 3.0W group ($99.75{\pm}6.64{\mu}m$), and between 1.0W group($44.54{\pm}6.99{\mu}m$) and 4.0W group($111.36{\pm}4.50{\mu}m$), and between 2.0W group($98.01{\pm}4.53{\mu}m$) and 4.0W group($111.36{\pm}4.50{\mu}m$)(P<0.05). 3. The coagulated layer depth was deeper in the irradiated specimens with higher power. There was a statistical significance in the difference of coagulated layer depth between 1.0W group($31.82{\pm}8.99{\mu}m$) and 3.0W group($55.99{\pm}20.94{\mu}m$), and between 1.0W group($31.82{\pm}8.99{\mu}m$) and 4.0W group($83.68{\pm}10.34{\mu}m$)(P<0.05). From this study, the results demonstrated that the effects of a pulsed Nd:YAG laser irradiation on gingival tissues seemed to depend on the laser power and that the irradiation with high power could be harmful to adjacent healthy tissue.