• Journal of Yeungnam Medical Science
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• 제26권1호
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• pp.1-14
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• 2009

Human bone marrow-derived mesenchymal stem cells (MSCs) are a rare population of undifferentiated cells that have the capacity of self renewal and the ability to differentiate into mesodermal phenotypes, including osteocytes, chondrocytes, and adipocytes in vitro. Recently, MSCs have been shown to reside within the connective tissue of most organs, and their surface phenotype has been well analyzed. Many reports showed that transplanted MSCs enhanced regeneration as well as functional improvement of damaged organs and tissues. The wide differentiation plasticity of MSCs was expected to contribute to their demonstrated efficacy in a wide variety of experimental animal models and in human clinical trials. However, new findings suggest that the ability of MSCs to alter the tissue microenvironment via secretion of soluble factors may contribute more significantly than their capacity for differentiation in tissue repair. This review describes what is known about the cellular characteristics and differentiation potential of MSCs, which represent a promising stem cell population for further applications in regenerative medicine.

• Biomaterials and Biomechanics in Bioengineering
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• 제2권2호
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• pp.61-69
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• 2015

Undifferentiated stem cells are being studied to obtain information on the therapeutic potential of isolates that are produced. Dental Pulp Stem Ccell (DPSC) may provide an abundant supply of highly proliferative, multipotent Mesenchymal Stem Cells (MSC), which are now known to be capable of regenerating a variety of human tissues including bone and other dental structures. Many factors influence DPSC quality and quantity, including the specific methods used to isolate, collect, concentrate, and store these isolates once they are removed. Ancillary factors, such as the choice of media, the selection of early versus late passage cells, and cryopreservation techniques may also influence the differentiation potential and proliferative capacity of DPSC isolates. This literature review concludes that due to the delicate nature of DPSC, more research is needed for dental researchers and clinicians to more fully explore the feasibility and potential for isolating and culturing DPSCs extracted from adult human teeth in order to provide more accurate and informed advice for this newly developing field of regenerative medicine.

• 대한의생명과학회지
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• 제28권4호
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• pp.290-297
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• 2022

Through previous studies, the central nervous system (CNS) was collected by dividing the scuttle fly into larval, pupa, and adult stages by developmental stage, and the morphological characteristics were observed. In situ hybridization (ISH) using the collected central nervous system, it was possible to confirm the location and extent of expression of the neurotransmitter corazonin (Crz) at each stage of development. In this study, paraffin specimens were prepared using central nervous system tissues of 3rd instar larval stage of scuttle fly, which had completed in situ hybridization, and general histochemical staining (hematoxylin-eosin, H-E) and special histochemical staining (luxol fast blue-cresyl violet) was performed to observe the histological and cytological morphology characteristics of corazonin neurons. As a result, a variety of nerve cell body existed between many myelin sheath. The corazonin neurons compose cortex of central nervous system with other neurons congregating in this tissue and show larger cell body relatively in neurohistochemical analysis.

• Parasites, Hosts and Diseases
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• 제34권1호
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• pp.59-68
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• 1996

만손열두조충의 스파르가눔(흰쥐에서 적출한 r-스파르가눔, 뱀에서 적출한 s-스파르가눔)과 성충을 재료로 하여 젖산탈수소효소와 말산탈수소효소의 조직내 분포 및 동위효소의 특징을 효소조직화학적 방법과 전기영동뎁으로 조사하였다. LDH와 WH는 외피하근층에서 강한 활성이 나타났으며, 실질조직(parenchyma)에서는 약하게 나타났다. 그러나 nH는 스파르가눔의 외피조직 에서도 활성이 나타났으나 성충의 외피조직에는 나타나지 않았다. LDH의 동위효소 유형은 5-스파르가눔, s-스파르가눔과 성충에서 각각 2개, 4개, 2개가 분리되었고, 45 kDa의 분회이 공통적으로 주분획이었으며 sinH의 동위효소는 5-스파르가눔, r-스파르가눔과 성충에서 각각 2개, 3개 4개의 분획이 분리되었고, IEF에 의해 성충에 존재하는 4개의 tmH 동위효소 분획의 등전점(Pl)은 각각 6.0, 6.5, 6.7, 7.1이었으며, 이 중 6.0이 주분획이었다. 또 최적 pH는 7이나 활성 범위가 pH 6 ~8이었고. 최적온도는 $40^{\circ}C$였으며, $50^{\circ}C$ 이상에서는 활성이 급격히 감소하였다 mH의 최적 활성도는 s-스파르가눔, r-스파르가눔과 성충에서 각각 19.4, 24.5, 108.0이었다. 위의 결과로 보아, 외피하근층으로 흡수된 양분은 충체 중앙으로 이동하면서 산화분해되며 유충에 비해 성충에서 물질 대사가 활발함을 알 수 있고, 또한 만손열두조충의 스파르가눔과 성충이 숙주와 기생 장소를 달리하지만 기생 환경에 따라 젖산탈수소효소와 말산탈수소효소의 동위효소들이 활성을 달리하므로써 숙주 환경에 적응한다는 사실을 알 수 있다.

• Journal of Periodontal and Implant Science
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• 제28권4호
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• pp.691-703
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• 1998

The 16S rRNA analyzing method is a bacterial identification method that is useful in identifying bacteria which is difficult to do by other means. The following 7 types of bacteria which are Treponema, A. actinomycetemcomitans, P. gingivalis, Fusobacterium, B. forsythus, P. intermedia, P. micros were evaluated in order to study their distribution among patients with adult periodontitis. The 16S rRNA analyzing method was used to compare bacterial distribution among 3 groups. Subgingival plaque acquired from the affected sites(pocket depth ${\geq}6mm$) of 29 patients with adult periodontitis were grouped as the experimental group while plaque from the non-affected sites(pocket depth ${\leq}3mm$) were grouped as control 2 and finally plaque acquired from students with healthy periodontal tissues were grouped as control 1. The results are as follows ; 1. The distribution of Treponema was 12.5% for control 1, 21.4% for control 2 and 75.4% for the experimental group. For A. actinomycetemcomitans the distribution was 0.5%, 19.0%, 44.4% in respect to the order of groups mentioned above. P.gingivalis showed 10.5%, 43.1%, 94.0% distribution, Fusobacterium 33.0%, 48.3%, 81.0% distribution, B. forsythus 9.5%, 17.2%, 65.9% distribution, P. intermedia 1.0%, 12.1%, 26.3% distribution and finally P. micros 5.0%, 19.0%, 48.7% respectively. In all 7 types of bacteria, the experimental group showed higher bacterial distribution compared to the other two groups with statistically significant difference. 2. In the case of Treponema, A. actinomycetemcomitans, gingivalis,Fusobacterium, B. forsythus, P. intermedia, P. micros showed significant difference between control 1 and 2. These results suggest that the 16S rRNA analyzing method which was applied on Koreans for the first time could be utilized and useful in finding potential pathogens of periodontal disease.

• Applied Microscopy
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• 제17권1호
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• pp.47-64
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• 1987

Morphological difference of the renal glomerulus at different age groups have been studied in young (three month-old), adult (twelve month-old) and old (thirty month-old) Fisher strain 344 rats. Pieces of the tissues were taken from renal corticies prefixed with 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1 M Millonig's phosphate buffer, pH 7.3), following by post-fixation with 1% osmium tetroxide (0.1 M Millonig's phosphate buffer, pH 7.3) and embedded within Araldite. The ultrathin sections contrasted with uranyl acetate and lead citrate were observed under a JEM 100CX electron microscope. The mean thickness of glomerular basal lamina and Bowman's capsule were determined by measuring the thinnest portion of basal lamina, and by taking the average of 50 readings from electron micrographs at different ages. The numerical changes of the slit pores were compared based upon the numbers over the length of 10um of glomerular basal lamina. The results were as follow: 1. The thickness of glomerular basal lamina is increased during aging; 140.4 nm in young rats, 270.0 nm in adult ones, and 437.8 nm in old ones. 2. The thickness of basal lamina of parietal cells of Bowman's capsule is 187.5 nm in young rats, 914.0 nm in adult ones, and 2850.0 nm in old ones. 3. The numbers of the slit pores of basal lamina are reduced during aging, 30.3 slit pores/$10{\mu}m$ in adult ones, and 24.2 slit pores/$10{\mu}m$ in old ones. 4. Accumulation of dense intracytoplasmic filamentous material in the parietal cells of Bowman's capsule is increased in the vicinity of the basal lamina during aging. The proximal tubule-like epithelial cell in Bowman's capsule is observed at one glomerulus in a young rat. 5. The endothelial cells are edematous and form balloon-like structure protruding into capillary lumen in young and old rats. 6. Cytoplasm of the podocyte shows a variety of alteration during aging, such as swelling of mitochondria and of endoplasmic reticulum, and increase of microtubules, microfilaments, lysosomes and lamellated myelin structures, etc. Accumulation of dense intracytoplasmic material in the foot processes is increased in the vicinity of the basal lamina during aging. The podocytic membrane-like structures are seen in young and o]d rats. 7. The mesangial matrices and mesangial cells are increased during aging, and slight swelling of endoplasmic reticulum and Golgi cisternae in young and old rats.

• 한국식물병리학회지
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• 제3권2호
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• pp.93-99
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• 1987

포장에서 도열병에 대하여 저항성이 다른 6개의 벼 품종을 일정한 환경조건에서 재배하여 벼 잎에 함유되어 있는 탄수화물, 아미노산 및 페놀화합물 함량과 식물의 여러 발육시기 및 벼 잎의 나이가 어떠한 관계가 있는지 연구하였다. 벼가 발육하는 동안 벼 잎에 함유되어 있는 탄수화물, 총 아미노산 및 페놀 화합물의 함량에 있어서 감수성 품종과 성체식물저항성 품종간에 유의차는 없었다. 단지 성체식물저항성 품종인 도봉만이 식물이 발육하는 동안 다른 품종에 비해 inositol함량이 가장 적었다. sucrose, inositol, glucose 및 fructose 함량은 모든 품종에서 5엽기보다 8엽기에서 증가하였으나 12엽기에서는 약간 감소하였다. 반면에 총 아미노산과 페놀화합물은 식물이 발육하는 동안 점차로 감소하였다. 건전한 5엽이 노쇠함에 따라 가용성 아미노산과 페놀화합물의 함량은 점차 증가하였으나 품종간의 품종간의 유의차는 없었다. 특히 도봉품종의 노쇠한 5엽에서 페놀화합물이 가장 높았다. 벼가 성숙하여 감에 따라 또한 노쇠한 벼 잎에서 도열병에 대하여 저항성이 증가되는 것은 아마도 도열병의 발생에 상이하게 작용하는 벼의 발육과 벼 잎이 노쇠하는 동안에 일어나는 생리적인 변화에서 기인하는 상이한 현상일지도 모른다.

• 한국발생생물학회지:발생과생식
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• 제3권1호
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• pp.101-105
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• 1999

N-Methylpurine-DNA glycosylase (MPG)는 DNA에서 N-methylpurine과 다른 손상된 purine기를 제거하는 DNA 회복 효소이다. 생쥐의 임신 8일 후의 태아조직부터 생후 400일까지의 조직들로부터 RT-PCR 방법으로 MPG mRNA 발현을 조사하였다. MPG mRNA는 태아 형성기동안 많은 양이 발현되었으며, 특히 15일에서 가장 높게 발현되었다. 태반에서의 MPG mRNA는 8 p.c. (post coitum)부터 18 p.c. 까지 계속적으로 감소하였다. 태아 형성기의 뇌와 간 조직에서 높은 mRNA 발현을 보였으나, 400일 되는 성체에서는 현저히 감소하였다. 부정소, 정낭, 정소, 정관, 난소, 난관 그리고 자궁 등의 생식기관에서의 MPG mRNA는 비교적 높게 발현되었고, 그들 중 부정소에서의 발현 정도가 가장 높았다. 이러한 결과들로 보아 MPG 유전자는 태아 발생단계 및 조직 특이적으로 발현됨을 알 수 있었다.

• 생명과학회지
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• 제19권8호
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• pp.1067-1072
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• 2009

성체흰쥐의 경우 항암제인 싸이클로포스파마이드(CY)처리로 퇴축된 가슴샘은 2주 후에 정상조직으로 재생된다. 가슴샘 발생과정에서 이미 알려진 SDF-1 신호전달의 중요성과는 달리 성체의 가슴샘 재생과정에서 그 역할에 관해서는 알려진 바 전혀 없다. 본 연구의 목적은 발생중인 가슴샘에서 발현이 증가된다고 이미 알려져 있는 SDF-1이 성체의 가슴샘재생과정에서 어떤 발현 양상을 보이는지를 조사하는 것이다. 본 연구에서는 사이클로포스파마이(cyclophosphamide: CY)를 투여하여 가슴샘의 급성 퇴축을 유발시킨 후, 가슴샘 재생과정동안 SDF-1의 발현 특성을 면역조직화학, 이중면역염색 형광법, 역전사 중합효소 연쇄반응법을 이용하여 조사하였다. 그 결과, SDF-1은 가슴샘의 급성 퇴축 이후 7일째 되는 시기에 mRNA와 단백질의 양이 급격히 증가하였으며, 이중면역염색 형광법을 통해 큰포식 세포와 위치적 분포가 일치함을 확인하였다. 따라서, 본 연구 결과들을 통해 SDF-1은 가슴샘의 급성 퇴축 초기 과정에서 나타나는 손상된 세포를 처리하는 큰포식 세포의 기능 조절에 관여할 것으로 생각된다.

• Toxicological Research
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• 제14권2호
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• pp.183-191
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• 1998

It has been reported that 50~70% of child asthma, bronchial asthma in adult, and allergic rhinitis are caused by house dust mite. The antigen extracted from house dust mite has been used for effective treatment against allergic diseases and for clinical test. This house dust mite antigen has been entirely imported from abroad. However, the composition and content of all the antigen imported vary from a brand to other brand. Thus, we need to standardize the composition and content of the antigen by developing it domestically. We proceeded pre-clinically general pharmacological test and toxicological test that are required for the eventual human use by utilizing the house dust mite cultured in Korea. In order to obtain information on general pharmacological tests such as its toxic signs in tissues or organs which are mainly affected, we examined the effect of house dust mite on the tensions of the isolated tissues and heart rates of cardiac muscle by recording with force displacement transducer of polygragh (Glass Model 7). We determined lethality of antigen extracted from house dust mite in mice and guinea pigs. We examined acute and subacute toxicity by administrating house dust mite extract of 500, 100, 20 times of the expected clinical dose. In male and female mice and guinea pigs, given a sigle intraperitoneal dose of antigen, $LD_{50}$ values were over 5.0 $\textrm{m}{\ell}$/kg, respectively. In animals administrated with house dust mite, there were no significant change of clinical symptom, body weight, food consumption, water consumption, eye examinations, urinalysis, blood biochemistry, and histopathological examinations in any animals tested. We found no toxic effect of this house dust mite. These results show that the house dust mite cultured by us could be used in the development of medicine against allergic diseases caused by the antigen of house dust mite.