Evaluation of the rat tissue reaction to experimental new resin cement and mineral trioxide aggregate cement

Yang, Won-Kyung,Ko, Hyun-Jung,Kim, Mi-Ri The Korean Academy of Conservative Dentistry 2012 Restorative Dentistry & Endodontics Vol.37 No.4

Objectives: New resin cement (NRC) has been developed as a root repairing material and the material is composed of organic resin matrix and inorganic powders. The aim of this study was to compare the rat subcutaneous tissue response to NRC and mineral trioxide aggregate (MTA) cement and to investigate the tissue toxicity of both materials. Materials and Methods: Sixty rats received two polyethylene tube-implants in dorsal subcutaneous regions, MTA and NRC specimens. Twenty rats were sacrificed respectively at 1, 4 and 8 wk after implantation and sectioned to 5 ${\mu}m$ thickness and stained with Hematoxylin-Eosin (H-E) or von-Kossa staining. The condition of tissue adjacent to the implanted materials and the extent of inflammation to each implant were evaluated by two examiners who were unaware of the type of implanted materials in the tissues. Data were statistically analyzed with paired t-test (p < 0.05). Results: In specimens implanted with both NRC and MTA, severe inflammatory reactions were present at one wk, which decreased with time. At eighth wk, MTA implanted tissue showed mild inflammatory reaction, while there were moderate inflammatory reactions in NRC implanted tissue, respectively. In NRC group, von-Kossa staining showed more calcification materials than MTA group at eighth wk. Conclusions: It was concluded that the calcium reservoir capability of NRC may contribute to mineralization of the tissues.

Evaluation of the rat tissue reaction to experimental new resin cement and mineral trioxide aggregate cement

Won-Kyung Yang,Hyun-Jung Ko,Mi-Ri Kim 大韓齒科保存學會 2012 Restorative Dentistry & Endodontics Vol.37 No.4

Objectives: New resin cement (NRC) has been developed as a root repairing material and the material is composed of organic resin matrix and inorganic powders. The aim of this study was to compare the rat subcutaneous tissue response to NRC and mineral trioxide aggregate (MTA) cement and to investigate the tissue toxicity of both materials. Materials and Methods: Sixty rats received two polyethylene tube-implants in dorsal subcutaneous regions, MTA and NRC specimens. Twenty rats were sacrificed respectively at 1, 4 and 8 wk after implantation and sectioned to 5 μm thickness and stained with Hematoxylin-Eosin (H-E) or von-Kossa staining. The condition of tissue adjacent to the implanted materials and the extent of inflammation to each implant were evaluated by two examiners who were unaware of the type of implanted materials in the tissues. Data were statistically analyzed with paired t-test (p < 0.05). Results: In specimens implanted with both NRC and MTA, severe inflammatory reactions were present at one wk, which decreased with time. At eighth wk, MTA implanted tissue showed mild inflammatory reaction, while there were moderate inflammatory reactions in NRC implanted tissue, respectively. In NRC group, von-Kossa staining showed more calcification materials than MTA group at eighth wk. Conclusions: It was concluded that the calcium reservoir capability of NRC may contribute to mineralization of the tissues.

Evaluation of the rat tissue reaction to experimental new resin cement and mineral trioxide aggregate cement

양원경,고현정,김미리 대한치과보존학회 2012 Restorative Dentistry & Endodontics Vol.37 No.4

Objectives: New resin cement (NRC) has been developed as a root repairing material and the material is composed of organic resin matrix and inorganic powders. The aim of this study was to compare the rat subcutaneous tissue response to NRC and mineral trioxide aggregate (MTA) cement and to investigate the tissue toxicity of both materials. Materials and Methods: Sixty rats received two polyethylene tube-implants in dorsal subcutaneous regions, MTA and NRC specimens. Twenty rats were sacrificed respectively at 1, 4 and 8 wk after implantation and sectioned to 5 μm thickness and stained with Hematoxylin-Eosin (H-E) or von-Kossa staining. The condition of tissue adjacent to the implanted materials and the extent of inflammation to each implant were evaluated by two examiners who were unaware of the type of implanted materials in the tissues. Data were statistically analyzed with paired t-test (p < 0.05). Results:In specimens implanted with both NRC and MTA, severe inflammatory reactions were present at one wk, which decreased with time. At eighth wk, MTA implanted tissue showed mild inflammatory reaction, while there were moderate inflammatory reactions in NRC implanted tissue, respectively. In NRC group, von-Kossa staining showed more calcification materials than MTA group at eighth wk. Conclusions: It was concluded that the calcium reservoir capability of NRC may contribute to mineralization of the tissues.

Significance of Serology by Multi-Antigen ELISA for Tissue Helminthiases in Korea

JIN YAN,김은민,최민호,오명돈,홍성태 대한의학회 2017 Journal of Korean medical science Vol.32 No.7

It is clinically important to differentiate tissue-invading helminthiasis. The purpose of this study was to assess the specific immunoglobulin G (IgG) antibody positive rates for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis 4 helminthiases from 1996 to 2006 using multi-antigen enzyme-linked immunosorbent assay (ELISA) in Korea. Results of 6,017 samples, which were referred to our institute for serodiagnosis, were analyzed. The subjects with positive serum IgG antibodies were 1,502 (25.0%) for any of the 4 helminthiases. The overall positive numbers for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis were 728 (12.1%), 166 (2.8%), 729 (12.1%), and 263 (4.4%), respectively. The positive serologic reaction to multi-antigens was determined in 309 (20.6%) of the 1,502 total seropositive subjects. Those with multi-antigen positivity were regarded as positive for the antigen of strongest reaction but cross-reaction to others with weak positive reaction. Annual seropositive rates for those 4 tissue helminthiases ranged from 12.1% to 35.7%. The highest rate was observed in age from 60 to 69 years old and prevalence of men (27.4%; 1,030/3,763) was significantly higher than of women (19.1%; 332/1,741). Hospital records of 165 ELISA positive patients were reviewed to confirm correlation with their clinical diagnosis. Paragonimiasis was highly correlated as 81.8% (9/11), cysticercosis 29.9% (20/67), clonorchiasis 29.0% (20/69), and sparganosis 11.1% (2/18). In conclusion, the multi-antigen ELISA using 4 helminth antigens is useful to differentiate suspected tissue-invading helminthiases, especially ELISA diagnosis of paragonimiasis is reliable. The seropositivity is still high among suspected patients in Korea.

연조직 결손을 일으킨 가토에서 진피 이식재에 따른 조직반응 비교

하현,김선국,유선열,Ha, Hyun,Kim, Sun-Kook,Ryu, Sun-Youl 대한구강악안면외과학회 2007 대한구강악안면외과학회지 Vol.33 No.2

The augmentation of soft tissue defects is one of the critical problems in the oral and maxillofacial surgery. Various types of graft materials, both autologous and non-autologous, have been used for the augmentation of soft tissue in the facial region. However, it is not easy to choose an ideal material for soft tissue augmentation because each has its advantages and disadvantages. An ideal graft material should meet the following criteria : it should not leave a scar at the area from which it was taken; should have less likelihood of causing infection; should feel natural after implanted; and should be not absorbed. Among the materials meeting these criteria, human dermis and artificial dermis are commonly used for clinical purposes. The present study was aimed to investigate and compare the resorption rate and the histological change following the use of the autologous dermis, the human homogenous dermis $Alloderm^{(R)}$, and the artificial dermis $Terudermis^{(R)}$ to reconstruct the soft tissue defect. Twenty mature rabbits of either sex, weighing about 2 ㎏, were used. Each rabbit was transplanted with the autologous dermis, $Alloderm^{(R)}$, and $Terudermis^{(R)}$ size $1{\times}1-cm$ at the space between the external abdominal oblique muscle and the external abdominal oblique fascia. They were then divided into 4 groups (n=5 each) according to the time elapsed after the surgery: 1, 2, 4, and 8 weeks. The resorption rate was calculated by measuring the volume change before and after the transplantation, and H-E stain was preformed to observe the histological changes. The resorption rate after 8 weeks was 21.5% for the autologous dermis, 16.0% $Alloderm^{(R)}$, and 36.4% $Terudermis^{(R)}$, suggesting that $Alloderm^{(R)}$ is the most stable while $Terudermis^{(R)}$ is the most unstable. In microscopic examinations, the autologous dermis graft was surrounded by inflammatory cells and showed foreign body reactions. The epidermal inclusion cyst was observed in the autologous dermis graft. $Terudermis^{(R)}$ and $Alloderm^{(R)}$ demonstrated neovascularization and the progressive growth of new fibroblast. The results suggest that $Terudermis^{(R)}$ and $Alloderm^{(R)}$ can be availably for substituting the autologous dermis.

수종의 봉합사의 조직반응에 관한 비교연구

김재석,박준봉,이만섭,허익,Kim, Jae-seok,Park, Joon-Bong,Lee, Man-Sup,Herr, Yeek 대한치주과학회 2002 Journal of Periodontal & Implant Science Vol.32 No.1

The purpose of this study is to evaluate histologically the tissue response and resorption of various nonresorbable and resorbable suture materials used for periodontal surgery, using a subcutaneous model on the dorsal surface of the rat. In this study, 10 Sprague-Dawley male rats (mean BW 150gm) were used and the commercially available materials included polyglactin 910, pain gut, nylon, e-PTFE. Animals were sacrificed at 3 days, 1, 2 and 4 weeks after implantation of various nonresorbable and resorbable suture materials. Specimens were prepared with Hematoxylin-Eosin stain for light microscopic evaluation. The results of this study were as follows: 1. Resorption : The resorption of plain gut was showed at 1 week after implantation, was lost their structure and almost resorbed at 4 weeks. The resorption of polyglactin 910 was started at 2 weeks and slowly absorbed untill 4 weeks. 2. Tissue response : Plain gut showed persistent and severe inflammatory reactions from 3 days to 4 weeks. Polyglactin 910, e-PTFE and nylon showed mild inflammatory reactions. Suture material should be biocompatible and be able to be functioned until tissue tensile strength reaches maximum level. In this study, polyglactin 910, nylon and e-PTFE are considered to be proper suture materials for periodontal surgery.

Ginkgo Biloba Extract가 마우스 피부 및 공장 소낭선의 방사선감수성에 미치는 영향

신경환(Kyung Hwan Shin),하성환(Sung Whan Ha) 대한방사선종양학회 1998 Radiation Oncology Journal Vol.16 No.2

목 적 : 혈관수축이완작용 및 혈액점도저하의 약리작용을 가져 말초혈관의 혈류를 증가시키는 것으로 알려진 은행잎 추출물인 Ginkgo biloba extract(GBE) 투여후 방사선 조사시 마우스 종양에서 방사선 효과가 증강됨이 확인되었다. 즉 저산소세포 분획이 감소되었으며 따라서 암조직의 혈류증가가 간접적으로 증명되었다. 방사선효과 증강제인 경우 암조직에 대한 효과가 정상조직에 대한 효과보다 더 커야한다는 것은 필수적이다. 이에 저자들은 GBE 투여후 방사선조사시 마우스 정상조직 급성 반응의 증가여부 및 그 정도를 확인하기 위하여 본 실험을 시행하였다. 대상 및 방법 : 방사선에 대한 급성 피부 반응의 측정 및 공장 재생 소낭선 측정을 위해서 C3H 마우스를 방사선 단독 조사군과 GBE 투여후 방사선조사군으로 나누었다. GBE는 방사선조사 24시간 전과 1시간 전에 각각 복강 내에 2회 주사하였다. 급성 피부 반응 측정 실험에서는 30-50Gy가 마우스 우측 하지에 조사되었고, 공장 재생 소낭선 측정 실험에서는 11-14Gy가 마우스 전신에 조사되었다. 결 과 : 방사선에 의한 급성 피부반응 점수 2.0 이상에 해당하는 RD50는 방사선 단독조사군에서 44.2Gy(40.6-48.2Gy)이었고, GBE 투여후 방사선 조사시에는 44.4Gy(41.6-47.4Gy)로서 GBE에 의한 영향이 없었다. 방사선 단독 조사군 및 GBE 투여후 방사선조사군의 각 방사선량에 따른 마우스 공장 재생 소낭선의 수는 차이를 보이지 않았다(p=0.57-0.94). 평균치사선량(D0)은 방사선 단독조사시 1.80Gy(1.57-2.09Gy), GBE 투여후 방사선조사를 병용시 1.88Gy(1.65-2.18Gy)로서 GBE에 의한 영향이 없었다. 결 론 : C3H 마우스에서 방사선에 의한 급성 정상조직 손상은 GBE에 의하여 전혀 증가되지 않는 것으로 판단되며 이미 증명된 종양세포에 대한 치료효과의 증강과 더불어 방사선치료시 GBE를 병용함으로써 치료적 이득을 얻을 수 있을 것으로 예상된다. Purpose : Ginkgo biloba extract(GBE) is known to increase the peripheral blood circulation. This study was designed to evaluate the effect of GBE on the acute normal tissue radiation reaction. Materials and Methods : C3H mice were divided into two groups, radiation alone and two doses GBE plus radiation, for both acute skin reaction and jejunal crypt assay. GBE was given i.p. one hour before irradiation with priming dose given one day earlier. Thirty to Fifty Gy for acute skin reaction and 11 to 14 Gy for jejunal crypt were irradiated to right hind leg and whole body, respectively. Results : Radiation doses(RD50) for peak skin score of 2.0 were 44.2Gy (40.6-48.2Gy) for radiation alone and 44.4Gy(41.6-47.4Gy) for two doses GBE plus radiation, showing no effect of GBE on acute radiation skin damage. The numbers of regenerating jejunal crypts per circumference were also almost the same for each radiation dose level(p=0.57-0.94), and the mean lethal doses(Do) were 1.80Gy(1.57- 2.09Gy) for radiation alone and 1.88Gy(1.65-2.18Gy) for two doses GBE plus radiation, indicating no effect of GBE on jejunal crypt cell survival after radiation. Conclusion : GBE doesn't increase acute normal tissue radiation reaction in this model system. As GBE was verified to enhance radiation effect on tumor, high therapeutic gain is expected when GBE is combined with radiation therapy.

Injectable hydrogels delivering therapeutic agents for disease treatment and tissue engineering

Jin Hyun Lee 한국생체재료학회 2018 생체재료학회지 Vol.22 No.4

Background: Injectable hydrogels have been extensively researched for the use as scaffolds or as carriers of therapeutic agents such as drugs, cells, proteins, and bioactive molecules in the treatment of diseases and cancers and the repair and regeneration of tissues. It is because they have the injectability with minimal invasiveness and usability for irregularly shaped sites, in addition to typical advantages of conventional hydrogels such as biocompatibility, permeability to oxygen and nutrient, properties similar to the characteristics of the native extracellular matrix, and porous structure allowing therapeutic agents to be loaded. Main body: In this article, recent studies of injectable hydrogel systems applicable for therapeutic agent delivery, disease/cancer therapy, and tissue engineering have reviewed in terms of the various factors physically and chemically contributing to sol-gel transition via which gels have been formed. The various factors are as follows: several different non-covalent interactions resulting in physical crosslinking (the electrostatic interactions (e.g., the ionic and hydrogen bonds), hydrophobic interactions, π-interactions, and van der Waals forces), in-situ chemical reactions inducing chemical crosslinking (the Diels Alder click reactions, Michael reactions, Schiff base reactions, or enzyme-or photo-mediated reactions), and external stimuli (temperatures, pHs, lights, electric/magnetic fields, ultrasounds, or biomolecular species (e.g., enzyme)). Finally, their applications with accompanying therapeutic agents and notable properties used were reviewed as well. Conclusion: Injectable hydrogels, of which network morphology and properties could be tuned, have shown to control the load and release of therapeutic agents, consequently producing significant therapeutic efficacy. Accordingly, they are believed to be successful and promising biomaterials as scaffolds and carriers of therapeutic agents for disease and cancer therapy and tissue engineering.

Comparative Efficacy of Various Formalin Fixatives for Molecular Diagnosis in Pathological Tissues

이우현,배문환,윤혜진,강인영,구명주,이재왕,전진현 대한의생명과학회 2022 Biomedical Science Letters Vol.28 No.4

Pathological tissue fixation using formalin has been widely used for histological samples in many hospitals and institutions. In general, formalin fixatives were either manufactured in laboratories or purchased commercially because of the risks and environmental concerns of handling organic compounds. In this study, the efficacy of three kinds of commercially purchased and one laboratory-made formalin fixative was compared in the PCR-based molecular diagnosis using the extracted DNA from formalin-fixed paraffin-embedded (FFPE) tissues. The quality of extracted DNA from FFPE tonsil tissues with four kinds of formalin solutions was evaluated, and PCR for beta-globin gene and microsatellite instabilities (MSI) tests for pentaplex panel markers were performed using the extracted DNA. There was no difference in PCR and MSI tests as molecular diagnoses regardless of the types of formalin used in this study. However, the total amount and average length of double-stranded DNA extracted from FFPE tonsil tissue showed significant differences according to the type of formalin fixative. Optimized formalin fixatives and methods for DNA extraction might be sophisticated to extract good quality DNA from the small size of specific tissue samples. Further studies are needed to select the most effective formalin fixative for histology and molecular pathology using human FFPE tissues.

양릉천(GB34),현종(GB39)에 대한 파장대별 레이저침 시술이 동통에 미치는 영향

윤대환 ( Dae Hwan Youn ),유평식 ( Pyung Sik Yoo ),김왕인 ( Wang In Kim ),김미래 ( Mi Rea Kim ),최동희 ( Dong Hee Choi ),나창수 ( Chang Su Na ) 경락경혈학회 2014 Korean Journal of Acupuncture Vol.31 No.4

Objectives : The purpose of this study is to examine the effects of laser acupuncture according to the wavelength(532 nm, 650 nm, 830 nm, 904 nm, and 1064 nm) at the acupoint of GB34ㆍGB39 on neuropathic pain rat induced by tibial and sural nerve transection(TST). Methods : Neuropathic pain in rats was induced by tibial nerve and sural nerve transection. The rats were divided into the intact group, the TST control group, and the laser acupuncture therapy group. The laser acupuncture therapy groups were then divided into subgroups with 532 nm(L532), 650 nm(L650), 830 nm(L830), 904 nm(L904), and 1064 nm(L1064) laser acupuncture therapy. The acupoint of GB34ㆍGB39 was selected, and laser acupuncture therapy was provided on both sides alternatively twice a week in a total of 6 sessions. Results : All the laser acupuncture groups showed a significant decrease in reaction time and force intensity. L532, L904, and L1064 groups showed a significant decrease in Bax, the L532 group showed a significant increase in Bcl-2, L532 and L1064 groups showed a significant decrease in the Bax/Bcl-2 ratio, and L532 and L650 groups showed a significant increase in mGluR5, as compared with the TST control group, among nerve tissue reaction. Conclusions : These results showed that laser acupuncture therapy at each of the wavelengths had some significance on neuropathic pain.