• Restorative Dentistry and Endodontics
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• v.27 no.2
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• pp.122-134
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• 2002

목적 : 근관 치료의 최종 목적인 근관계의 영구적인 충전을 위해 사용되는 근관 봉함제는 많은 연구와 개선을 거쳐서 현재는 다양한 성분의 봉함제가 시판되고 있다. 이중에서 레진이 주성분인 봉함제는 조작이 편리하고 흐름성이 좋으며 근관의 벽에 높은 밀폐성을 보이고 충분한 작업시간과 높은 방사선 불투과성을 가지는 장점을 가짐에도 불구하고 높은 초기 생체 독성을 나타내는 단점을 가지고 있다. 본 실험에서는 기존의 상용화된 제품 중 레진이 주성분인 두 종류의 봉함제(AH 26, AH plus)와 산화아연이 주성분인 봉함제(Pulp Canal Sealer EWT)와 국내에서 새로이 개발한 제품으로서 레진이 주성분인 두 종류의 봉함제(Adseal-1,2)를 생체조직에 매식하여 국소적인 반응을 비교하여 생체친화성을 알아보고자 하였다. 방법 : 수종 봉함제의 생체 친화성을 알아보기 위하여 64마리의 Sprague-Dawley rat을 사용하였다. 봉함제의 피하조직 매식을 위해 길이와 직경이 각각 5와 1.5mm인 폴리에틸렌 테프론 관을 사용하였으며 이를 에탄올과 증류수로 세척 한 후 고압증기멸균을 시행하였다. Rat에 대하여 케타민으로 복강내 마취를 시행한 후 배부를 면도하고 iodine으로 소독한 다음 네 곳에 절개를 시행하였으며 blunt dissection을 통해 깊이 10mm이상의 피하조직 pocket을 형성하였다. 각각의 봉함제를 제조사의 지시 에 따라 혼합 후 즉시 멸균된 테프론 관에 주사기를 이용하여 담은 다음에 봉함제가 흐르지 않게 유의하며 pocket내로 삽입하였으며 이때 16개의 관을 대조군으로 사용하기 위해 봉함제를 넣지 않은 상태로 삽입하였다. 이 후 절개 부위를 surgical gut suture로 봉합하였으며 1주일 후에 발사하였다. Rat을 1, 2, 4, 12주 후에 각 군 당 세 마리 씩 에테르 흡입을 통해 희생하였으며 이 때 한 마리씩의 대조군도 포함시켰다. 이 후 매식된 관을 주위 조직과 함께 제거하고 포르말린에서 48시간 고정시킨 후 파라핀에 포매한 다음에 micro-tome을 사용하여 6$\mu\textrm{m}$로 serial section을 시행하였다. 정중선 부위의 시편에 Hematoxylin-Eosin staining을 시행한 후 Olsson, Orstavik 그리고 Mjor 등의 방법에 따라 조직학적 변화를 관찰한 후 slight(1), moderate(2), severe inflammation(3)의 단계로 분류하였다. 얻어진 결과를 통계처리 프로그램인 Jandel사의 Sigmastat을 이용하여 Kruskal Wallis Test로 통계처리를 하였다. 결과 : (Table omitted) 결론 : 1) Pulp Canal Sealer를 제외한 모든 군에서 시간이 지남에 따라 유의성 있게 염증이 감소되는 양상을 보였다(p<0.05). 2) Pulp Canal Sealer는 1주, 2주, 12주에서 강한 염증반응을 보였다. 3) AH 26과 AH Plus에서는 1주, 2주에서 강한 염증반응을 보였으나 12주에서는 염증반응이 감소하였다. 4) 새로 개발된 봉함제 Adseal-1,2는 1주, 2주에서는 가장 약한 염증반응을 보이나 4주, 12주 후에는 AH Plus와 비슷한 수준의 염증 반응을 보였다. 5) Pulp Canal Sealer를 제외한 모든 군에서 인정할 만한 생체친화성을 보였다. 6) Adseal-2가 Adseal-1에 비하여 전반적으로 낮은 염증반응을 보였다. 7) 각 군간 결과의 차이에 통계적 유의성은 없었다(p>0.05).

• Journal of Chest Surgery
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• v.41 no.6
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• pp.679-686
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• 2008

Background: Cellular remnants in the bioprosthetic heart valve are known to be related to a host's immunologic response and they can form the nidus for calcification. The extracellular matrix of the decellularized valve tissue can also be used as a biological scaffold for cell attachment, endothelialization and tissue reconstitution. Thus, decellularization is the most important part in making a bioprosthetic valve and biological caffold. Many protocols and agents have been suggested for decellularization, yet there ave been few reports about the effect of a treatment with hypotonic solution prior to chemical or enzymatic treatment. This study investigated the effect of a treatment with hypotonic solution and the appropriate environments such as temperature, the treatment duration and the concentration of sodium dodecylsulfate (SDS) for achieving proper decellularization. Material and Method: Porcine aortic valves were decellularized with odium dodecylsulfate at various concentrations (0.25%, 0.5%), time durations (6, 12, 24 hours) and temperatures ($4^{\circ}C$, $20^{\circ}C$)(Group B). Same the number of porcine aortic valves (group A) was treated with hypotonic solution prior to SDS treatment at the same conditions. The duration of exposure to the hypotonic solution was 4, 7 and 14 hours and he temperature was $4^{\circ}C$ and $20^{\circ}C$, respectively. The degree of decellularization was analyzed by performing hematoxylin and eosin staining. Result: There were no differences in the degree of decellularization between the two concentrations (0.25% 0.5%) of SDS. Twenty four hours treatment with SDS revealed the best decellularization effect for both roups A and B at the temperature of $4^{\circ}C$, but there was no differences between the roups at $20^{\circ}C$. Treatment with hypotonic solution (group A) showed a better ecellularization effect at all the matched conditions. Fourteen hours treatment at $4^{\circ}C$ ith ypotonic solution prior to 80S treatment revealed the best decellularization effect. The treatment with hypotonic solution at $20^{\circ}C$ revealed a good decellularization effect, but his showed significant extracellular matrix destruction. Conclusion: The exposure of porcine heart valves to hypotonic solution prior to SDS treatment is highly effective for achieving decellularization. Osmotic treatment with hypotonic solution should be considered or achieving decellularization of porcine aortic valves. Further study should be carried out to see whether the treatment with hypotonic solution could reduce the exposure duration and concentration of chemical detergents, and also to evaluate how the structure of the extracellular matrix of the porcine valve is affected by the exposure to hypotonic solution.

• Korean Journal of Clinical Laboratory Science
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• v.37 no.1
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• pp.47-55
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• 2005

These studies were done to know decalcification methods to reduce the time of decalcification for quick bone tissue diagnosis. When bone tissue was decalcified with 10 % formic acid at room temperature, decalcification and hematoxylin & eosin (H&E) stains were complete and satisfactory after 12 hours, but some of the tissue sections fell off during staining. In this way, decalcification, H&E stains were complete and satisfactory after 24 hours, 36 hours and 48 hours, tissue sections didn't fall off during staining. When bone tissue was decalcified with 10 % formic acid in a $60^{\circ}C$ paraffin oven, decalcification and H&E stains were complete and satisfactory after 6 hours, but some tissue sections fell off during staining. In this way, decalcification and tissue sections were complete, with no falling off during staining after 8 hours, 10 hours, 12 hours, 14 hours, 24 hours, or H&E stains were satisfactory from 8 hours to 12 hours, but H&E stains appeared to reddish nucleus after 14 hours and 24 hours. Bone tissue was decalcified with 10 % formic acid for 6 hours, 12 hours and 24 hours at DECAL machine frequencies of 15 Hz and 45 Hz, and for 6 hours, 12 hours and 24 hours at a DECAL machine frequency of 90 Hz. Decalcification and H&E stains were complete and satisfactory after 6 hours at the 15 Hz and 45 Hz DECAL settings. Some of the tissue sections fell off during staining at the 15 Hz DECAL machine setting. At the 90 Hz setting, decalcification, H&E stains, and tissue sections were complete and satisfactory with no falling off during staining after 4 hours. In this way, decalcification, H&E stains, and tissue section were complete and satisfactory with no falling off during staining after 12 hours, 24 hours at all machine settings. Bone tissue was decalcified with 10 % formic acid for 6 hours, 12 hours and 24 hours at $37^{\circ}C$ 3 hours, 6 hours and 12 hours at $45^{\circ}C$ and 1 hours, 5 hours and 10 hours at $60^{\circ}C$ with the RHS-1 machine setting at 60Hz. At the temperatures of $37^{\circ}C$, $45^{\circ}C$, and $60^{\circ}C$ decalcification, H&E stains, and tissue sections were complete and satisfactory, with no falling off during staining except for after 6 hours at $37^{\circ}C$. 3 hours, 1 hours, or decalcification, H&E stains, and tissue sections were complete and satisfactory with no falling off during staining after 12 hours and 24 hours at $37^{\circ}C$, 6 hours and 12 hours at $45^{\circ}C$, and 5 hours at $60^{\circ}C$. But H&E stains appeared to reddish nucleus after 10 hours at $60^{\circ}C$. From the above reults, the authors were able to deduce that decalcification is accelerated by heat and frequency. We therefore think that it is necessary for machines which are similar to the RHS-1 machine to be maintained at the temperature evenly with agitation effect for quick decalcification.

• Radiation Oncology Journal
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• v.12 no.3
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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.

• Proceedings of the Ginseng society Conference
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• 2007.12a
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• pp.57-58
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• 2007

Purpose: Ginseng is a well-known medical plant used in traditional Oriental medicine. Korean red ginseng (KRG) has been known to have potent biological activities such as radical scavenging, vasodilating, anti-tumor and anti-diabetic activities. However, the mechanism of the beneficial effects of KRG on diabetes is yet to be elucidated. The present study was designed to investigate the anti-diabetic effect and mechanism of KRG extract in C57BL/KsJ db/db mice. Methods: The db/db mice were randomly divided into six groups: diabetic control group (DC), red ginseng extract low dose group (RGL, 100 mg/kg), red ginseng extract high dose group (RGH, 200 mg/kg), metformin group (MET, 300 mg/kg), glipizide group (GPZ, 15 mg/kg) and pioglitazone group (PIO, 30 mg/kg), and treated with drugs once per day for 10 weeks. During the experiment, body weight and blood glucose levels were measured once every week. At the end of treatment, we measured Hemoglobin A1c (HbA1c), blood glucose, insulin, triglyceride (TG), adiponectin, leptin, non-esterified fatty acid (NEFA). Morphological analyses of liver, pancreas and white adipose tissue were done by histological observation through hematoxylin-eosin staining. Pancreatic islet insulin and glucagon levels were detected by double-immunofluorescence staining. To elucidate an action of mechanism of KRG, DNA microarray analyses were performed, and western blot and RT-PCR were conducted for validation. Results: Compared to the DC group mice, body weight gain of PIO treated group mice showed 15.2% increase, but the other group mice did not showed significant differences. Compared to the DC group, fasting blood glucose levels were decreased by 19.8% in RGL, 18.3% in RGH, 67.7% in MET, 52.3% in GPZ, 56.9% in PIO-treated group. With decreased plasma glucose levels, the insulin resistance index of the RGL-treated group was reduced by 27.7% compared to the DC group. Insulin resistance values for positive drugs were all markedly decreased by 80.8%, 41.1% and 68.9%, compared to that of DC group. HbA1c levels in RGL, RGH, MET, GPZ and PIO-treated groups were also decreased by 11.0%, 6.4%, 18.9%, 16.1% and 27.9% compared to that of DC group, and these figure revealed a similar trend shown in plasma glucose levels. Plasma TG and NEFA levels were decreased by 18.8% and 16.8%, respectively, and plasma adiponectin and leptin levels were increased by 20.6% and 12.1%, respectively, in the RGL-treated group compared to those in DC group. Histological analysis of the liver of mice treated with KRG revealed a significantly decreased number of lipid droplets compared to the DC group. The control mice exhibited definitive loss and degeneration of islet, whereas mice treated with KRG preserved islet architecture. Compared to the DC group mice, KRG resulted in significant reduction of adipocytes. From the pancreatic islet double-immunofluorescence staining, we observed KRG has increased insulin production, but decreased glucagon production. KRG treatment resulted in stimulation of AMP-activated protein kinase (AMPK) phosphorylation in the db/db mice liver. To elucidate mechanism of action of KRG extract, microarray analysis was conducted in the liver tissue of mice treated with KRG extract, and results suggest that red ginseng affects on hepatic expression of genes responsible for glycolysis, gluconeogenesis and fatty acid oxidation. In summary, multiple administration of KRG showed the hypoglycemic activity and improved glucose tolerance. In addition, KRG increased glucose utilization and improved insulin sensitivity through inhibition of lipogenesis and activation of fatty acid $\beta$-oxidation in the liver tissue. In view of our present data, we may suggest that KRG could provide a solid basis for the development of new anti-diabetic drug.

• Tuberculosis and Respiratory Diseases
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• v.39 no.2
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• pp.131-140
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• 1992

In order to investigate the changes of hydroxyproline amount and pathologic finding in rat lung which were instilled the natural coal and free silica dust intratracheally, the subjects were divided into two groups as follows. The control group was only administered intratracheally 0.5 ml of normal saline, and the experimental groups were instilled at once the turbid solution containing 10 mg, 30 mg and 50 mg of natural coal and free silica dust each, subjects were sacrified at the 3rd and the 20th week each after the experiment. Hydroxyproline amount in the right upper lung was measured by Woessner method and HPLC (modified Dunphy) method, and the pathlogic finding of lung tissue were observed for hematoxylin-eosin staining, Bielschowski method and Masson's trichrome method. The results were as follows. 1) The wet lung weights of all experimental groups excluding in the groups instilled 10 mg and 30 mg of natural coal dust at 3rd week, were significantly increased (p<0.05) compared with control group. The weight in each free silica group was markedly increased (p<0.05) at 20th week compared with the same dose of natural coal dust group, while the weight in the same dose group of free silica dust was increased significantly at 20th week compared with at 3rd week. 2) The amount of hydroxyproline were significantly increased (p<0.05) in the natural coal and free silica groups at 20th week compared with the control groups, and in each experimental group instilled the same kind and dose of dust, its amount was markedly increased (p<0.05) at 20th week compared with at 3rd week. And also the hydroxyproline in 30 mg and 50 mg free silica groups increased markedly (p<0.05) at 20th week compared with the natural coal dust of the same dose. 3) The polymorphonuclear leukocytes, fibroblasts and macrophages in interstitium and alveolar space showed the increasing tendency in the free silica group more markedly than in the natural coal dust group. The exudate in alveolar space at 3rd week was disappeared at 20th week, and pneumoconiotic nodules observed microscopically in all experimental groups at 20th week, while the nodules apeared already at 3rd week in the 30 mg and 50 mg free silica dust groups. The significant increase of Hydroxyproline content in lung tissue and pneumoconiotic nodule formation in experimental groups found in this study indicate that the observation period, dust amount and kind of dust is important factors associated with pneumoconiosis. And these findings were generally more severe in free silica dust groups than in natural coal groups.

• The korean journal of orthodontics
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• v.34 no.1 s.102
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• pp.71-81
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• 2004

In this study, we attempt to investigate the mechanisms by which PDL cells regulate osteoclast formation and also tc know whether PDL retained their characteristic phenotype during tooth eruption and interdental separation. Rats were prepared at developmental days 21 (pre-root formation), 27(toot development), 34(advanced root formation/eruption) and at later times(adult rats). To induce severe resorption state of alveolar bone and tooth root, interdental separation with brass wire was performed between the lower first and second molars for 2 weeks in adult rats. Rat mandibles were demineralized and embedded in paraffin, and horizontal and frontal section were prepared for immuno-histochemical analysis using PDL-specific protein 22 (PDLs22), receptor activator of NFKB ligand (RANKL) and osteoprotegerin (OPG) antibodies. 1. Root formation and eruption stage of tooth development. 1) PDLs22 immunolocalization was observed in tooth follicle/PDL cells and osteoblasts throught out the root formation and eruption stages of tooth development. 2) RANKL expression became stronger at eruption stage than root formation stage of tooth development. 3) Strong expression of OPG was detected in follice/PDL cells of toot formation stage but it was decreased with tooth eruption. 2. Interdental separation between lower first and second molar 1) Comparared to normal animal, multinucleated osteoclasts and odontoclasts were markedly induced in the alveolar bone and tooth root with PDL remodeling in hematoxylin-eosin section. 2) PDLs22 expression was decreased with interdental separation. 3) RANKL expression was Increased with interdental separation in PDL fibroblasts, osteoblasts, odontoclasts and it lacunae, resorting dentin, cementum and bone matrix. 4) OPG expression was slightly decreased in the PDL cells adjacent to the alveolar bone and root surface with interdental separation. These results suggested that during tooth eruption and tooth movement, RANKL and OPG in the periodontal tissues are important determinants regulating balanced alveolar bone and tooth root resorption. And it is also suggested that PDL cells retained their characteristic phenotype during tooth eruption and interdental separation except for the short period of PDL remodeling.

• Applied Microscopy
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• v.15 no.2
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• pp.31-68
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• 1985

Authors are trying to unveil the ultrastructural organization of olfactory bulb, which has been summerized under light microscopic level or communicated only in some detail in different view point until now. For the critical point of view, since the phylogenetical approach will give the ultimate value in the correlative study between structural and functional bases (Brodal, 1969), the present study was carried out light and electron microscopic analyses of the structures of the neurons and synaptic organizations in olfactory bulbs from different animals in phylogenetical scale. We selected each one species from five animal classes: the house rabbit(Oryctolagus cuniculus var. domesticus [Gmelin]) from Mammalia, the domestic fowl (Gallus gallus domesticus Brisson) from Aves, the viper (Agkistrodon hylys [G.P. Pallas]) from Reptilia, a frog (Bombiana orientalis Boulenger) from Amphibia and the crussian carp (Carassius carassius [Linne]) from Pisces. For light microscopic study, samples were fixed in 10% formalin and paraffin sections were stained with hematoxylin-eosin. For the electron microscopic study, the tissues were fixed by perfusion through the heart or immersion with 1% paraform-aldehyde-glutaraldehyde mixture (phosphate buffer, pH 7.4), and final tissue block trimmed under dissecting microscope were osmicated (1% OsO4), they were embedded in Araldite or Epon 812, and ultrathin sections were made by LKB-V ultratome following the inspection of semi-thin sections stained with toluidine blue-borax solution. Ultra-thin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100CX electron microscope. We have summerized our morphological analyses as follows: 1. The olfactory bulb of rabbit, viper and frog shows the eight layers of fila olfactoria, glomerular, external granular, external plexiform, mitral cell, internal plexiform, internal granular, medullary but domestic fowl shows the five layers of glomerular, fibrillar, mitral, granular and medullary and the three layers of fibrilla, glomerular and medullary in crussian carp. The sharpness of demarcation between the layers shows deferential tendency according to phylogenetical order. 2. Mitral cells of vertebrate have large triangular or oval shape with spherical nuclei which contain not so much chromatin. The cytoplasm contains numerous cell organelles, of which Nissl's bodies or granular endoplasmic reticula arranged as parallel strands. Development of granular endoplasmic reticula were declined as the phylogentical grade is going lower. 3. Tufted cells of all animal are mostly spindle or polygonal contour and contain oval nuclei which located in periphery of cytoplasm. The nuclei of rabbit, fowl, viper and frog has relatively space chromatin, but a nucleus of crussian carp contain irregularly aggregated chromatin in karyoplasm. Their cytoplasmic volume and cell organelle contents are in between those of mitral cell and granular cell. They contain moderate amount of mitochondria, granular endoplasmic reticula, a few Golgi complex, polysomes, lysosome, etc. 4. Granule of cells of all the vertebrate amimals studied exhibit similar features; cells and their dense nuclei show spherical or oval contour, and they have the thin rim of cytoplasm which contain only a few cell organelles. 5. In rabbit, the soma of mitral cells were in contact with boutons with two types of synaptic vesicles, that is, round and flat vesicles, especially flat vesicles in boutons were showing reciprocal synapses. However, in domestic fowls, vipers, frogs and crussian carps, there were found boutons showing only spherical synaptic vesicles. 6. The boutons containing round synaptic vesicles were made contact with the some of tufted cell of olfactory bulb in the rabbits, fowls, vipers and frogs, but no synaptic boutons were observed in soma of tufted cells in crussian carps. In the frogs, there were observed dendrites were contact with the soma of tufted cells. 7. In the neuropils of plexiform, granular and glomerular layers olfactory bulbs in the vertebrate, the synapses were axo-large dendrites, axo-median and small dendrites, dendrodendritic, and axo-axonal contacts. However, in the neuropil of crussian carps, synapses were observed only in glomerular layer.

• Korean Journal of Veterinary Research
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• v.15 no.1
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• pp.57-67
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• 1975

The poxvirus group is considered to be a typical cytoplasmic inclusion forming virus. Every poxvirus has been reported to produce only one kind of inclusion in the infected tissues. A vague concept that inclusions of poxviruses are eosinophilic or acidophilic has prevailed. Although many papers and theories about the nature of the inclusion have been presented, most of them are not quite convincing on the point of the relations with virus multiplication, and an analysis of papers published showed that there seem to be many discrepancies in the descriptions of the nature of the poxvirus inclusions. Comparative studies on host-virus interaction with cowpox, orf, swinepox and fowlpox viruses which selected from each Group (I-IV) of poxviruses were performed from the morphological and virological standpoints. At first, in cowpox virus-FL cell system, as a comparative model, cytoplasmic inclusion, nucleic acid metabolism by autoradiography and detection of viral antigen by immunofluorescence were studied and obtained the results as follows: 1. The focus-like cytopathic effect (CPE) at early stage developed to entire culture at terminal stage of infection, and also the developing status of CPE was correlated to viral doses for inoculation. Two kinds of cytoplasmic inclusions which named A and B type were easily observed by Giemsa, hematoxylin-eosin (H & E) and May-Greenwald Giemsa (MGG) stainings in the infected cells. The B type inclusions were formed at early stage of infection and the A type inclusions were produced subsequently the B type formation. The B type which common type inclusion in poxviruses was a small compact or aggregate at early stage and developed to a large diffuse body at terminal stage of infection. On the other hand, the A type inclusion which depend upon the kind of virus was appeared as round and discrete shape, and its size and number was increased gradually during the culture period. It was characteristic to form distinct halos around the both types of inclusions in acid fixed, H & E stained preparations of infected cultures. The B type inclusion was always positive in Feulgen reaction and showed as DNA containing body but the A type inclusion was not. 2. In the relationship between inclusion and DNA metabolism of infected cells by the qualitative autoradiography using 3H-thymidine, the appearance of silver grains was coincided with B type inclusion but not with A type inclusion. This showed that the DNA synthesis was proceeded in all B type inclusions except those in the terminal stage with a diffuse form. This suggested that the B type inclusions are only sites of DNA synthesis and this was proceeded after the cell infection independently. The activity of DNA synthesis of the inclusions was nearly the same as that of the nucleic of normal cells and non-inclusion bearing cells. and non-inclusion bearing cells. Regardless of the size of the degree of DNA synthesis of the B type inclusion, inclusion bearing cells all showed remarkable suppression of nuclear DNA synthesis. 3. By the direct fluorescent antibody technique viral antigen in infected cells was detected. The B type inclusions have been proved to contain a great deal of viral antigen, whereas the basic substance of A type inclusion did not show antigenicity except the round edge. It was suggested that the round edge fluorescence might be caused by the glare of cytoplasmic viral antigen which pushed out and concentrated by the A type inclusion development. 4. Hemorrhagic red pock formations on chorioallantoic membrane of embryonated chicken egg had proved the characteristic of used viral strain. 5. By the above studies on the nature of two types of inclusions and the role they play in virus multiplication, it was concluded that the B type inclusion must be the site of the synthesis of viral DNA and protein as well as the site of the virus.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.123-131
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• 1982

The purpose of this study was to observe the responses of the remaining pulp tissue after pulpotomy upon the several kinds of $Ca(OH)_2$ products and the responses of periapical tissue upon some root canal filling materials after extirpation. For pulpotomy, the class V cavities were prepared on the premolars, molars and upper canines, and the pulp was amputated. Each drug was placed over the amputated tissue and cavity was sealed with zinc oxide eugenol cement. The drugs which were used for the study were Dycal (Caulk Co. U.S.A.), Cavitec (Kerr Co. U.S.A.), Calvital, Nobudyne and Neodyne (Neo Dental Chemical Products). For extirpation, the endodontic cavities were prepared on the lingual surfaces of anterior teeth, and the pulp tissues were extirpated as routine method. After enlarging, irrigation, and measuring of root length by taking X-ray, each root canal filling material was filled in the canal with gutta percha cone, and endodontic cavity was sealed with zinc oxide eugenol cement. Zinc oxide eugenol, $Ca(OH)_2$ (Eli Lilly Co. U.S.A.) and Vitapex (Neo Dental Chemical Products) were used as root canal filling materials. Animals were sacrificed after 1, 3 and 6 weeks following the operation. The teeth were decalcified in formic acid, sectioned and stained with hematoxylin eosin. Microscopic examination revealed as follows. 1. Dycal: The dentin bridge formation was observed at the 3rd week after pulpotomy. Inflammatory conditions which were infiltration of inflammatory cells and dilatation of blood vessels were kept in remaining pulp tissue at the 6th week. 2. Calvital: The dentin bridge was observed at the 1st week after pulpotomy. As the time clasped, the pulp tended to be the fibrous degeneration. 3. Cavitec, Nobudyne and Neodyne: In the case of Cavitec and Nobudyne, the incompleted and irregular dentin bridge was observed at the 6th week, and in Neodyne, was observed at the 3rd week. The severe inflammatory changes were seen in the remaining pulp tissue. As the time clasped, the fibrous degeneration tended to spread in the remaining pulp tissue. 4. $Ca(OH)_2$: Osteocementum was formed at the 3rd week, the matrix of cementum and dentin were resorted, and infiltration of lymphocytes was seen in periapical tissue when $Ca(OH)_2$ was used as canal-filling materials. S. ZOE and Vitapex The cementum like substance was seen in periapical portion at the 1st week, when ZOE and Vitapex were used as root canal filling materials. As the time elapsed, the matrix of cementum and dentin tended to be resorted. At the 6th week, the inflammatory condition of periapical tissue was continued in the case of ZOE, but was reduced in the case of Vitapex.