• 폴리머
• /
• 제28권5호
• /
• pp.382-390
• /
• 2004

생체적합성 천연재료 중 하나인 탈미네랄화된 골분 (demineralized bone particle, DBP)은 골형성단백질 (BMP)을 함유하고 있어 골수간엽줄기세포 (BMSCs)의 분화를 유도한다. 본 연구에서는 DBP를 함유한 폴리 락타이드 (PLA)와 락타이드-글리콜라이드 공중합체 (PLGA) 다공성 지지체를 용매 캐스팅/염추출법으로 제조하였고, 수은다공측정계 및 전자주사현미경을 이용하여 특성결정 하였다. BMSCs는 골분화 배지를 이용하여 조골세포로 분화시켜 Wright-Giemsa, Alizarin red, von Kossa 및 ALP 염색으로 확인하였다. DBP가 함유된 지지체와 DBP가 함유되지 않은 지지체에 BMSCs를 파종한 후 면역결핍 누드마우스의 피하에 삽입하여 이들의 골형성 정도를 비교하여 보았다. 제조한 지지체의 다공도는 $90.2\%$ 이상이었고 평균 다공크기도 69.1$\mu$m 이상이었다. BMSCs는 Wright-Giemsa, Alizarin red, von Kossa 및 ALP 염색결과 조골세포로 분화가 가능했으며, 동물실험을 수행한 결과 DBP가 함유된 지지체에서 칼슘침착 영역을 확인할 수 있었지만 DBP가 함유되지 않은 지지체에서는 칼슘침착 영역을 확인하지 못하였다. 결론적으로 DBP를 함유한 지지체에서 DBP와 BMSCs가 골형성에 중요한 요인으로 작용한다고 사료된다.

• Journal of Ginseng Research
• /
• 제37권4호
• /
• pp.401-412
• /
• 2013

Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to $319.3{\pm}65.9%$ as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 ${\mu}M$ each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI-1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.

• 폴리머
• /
• 제32권5호
• /
• pp.403-408
• /
• 2008

케라틴은 울, 머리카락, 손톱 등을 형성하는 섬유단백질의 주요성분으로 유용한 생체재료이다. 골수간염 줄기세포를 이용한 조직공학 적용을 위해 Poly(4-lactide-co-glycolide) (PLGA)에 함량별로 케라틴을 함유한 지지체를 용매 캐스팅/염 추출법을 이용하여 제조하였다. 제조된 지지체의 표면과 단면의 형태를 전자현미경(SEM)으로 관찰하고 특성분석을 위해 다공도, 표면 적심성, 물 흡수성, 그리고 열적성질을 분석하였다. 이 후 쥐에서 분리한 골수간엽줄기세포를 지지체에 파종하여 세포의 증식율을 (4,5-dimethylthiazol-2-yl)-2.5-diphenyl-tetrazolium bromide(MTT) 분석방법을 이용하여 측정하였다. 천연/합성 하이브리드 담체인 케라틴/PLGA 지지체는 PLGA 단독으로 제조된 지지체와 비교 시 골수간엽줄기세포의 생장에 유익한 환경을 제공함을 확인하였다.

• 대한수의학회지
• /
• 제31권2호
• /
• pp.131-135
• /
• 1991

The purpose of this study was designed to compare the storage stage of spermatozoa in the utero-vaginal (U-V) glands and the infundibular glands of high-fecundity hens. These laying hens were assigned to four groups by date intervals after last artificial inseminations. The U-V glands and the infundibular glands in the tissue preparation of the each hen uterus were observed microscopically, and also the appearance rates of spermatozoa-contained U-V glands were compared with those of the infundibular glands. 1. The appearance rates of spermatozoa-contained U-V glands were found to be 27.8, 28.8, 19.9 and 11.1% respectively at the hen groups of 1, 3, 7 and 10 days after artificial insemination. 2. The appearance rates of spermatozoa-contained infundibular glands were found to be 0.5, 1. 1, 0.6 and 0.4% of 1, 3, 7 and 10 days after AI and number of spermatozoa contained in a infundibular glands tended predominantly to be 1 to 2. So this study concluded as follows: The appearance rates of spermatozoa-contained glands were found to be higher in the U-V glands than in the infundibular glands and also spermatozoa number per gland were more numerous in U-V glands than in infundibular glands.

• Archives of Plastic Surgery
• /
• 제46권6호
• /
• pp.603-607
• /
• 2019

During a full-thickness skin graft procedure, the thickness of the harvested donor skin is adjusted based on the location of the recipient site and the judgment of the surgeon. Conventionally, the thickness of the harvested skin is roughly adjusted using surgical instruments such as scalpels and scissors. However, this method is not only time-consuming, but also requires effort to obtain both the desired thickness of the harvested skin and a smooth surface of that skin. Moreover, there is a possibility of skin perforation. Hence, the authors devised a method of adjusting harvested skin thickness using the Versajet Hydrosurgery System. The Versajet device is a handheld hydrosurgical tool that delivers a high-speed jet stream of saline solution, which enables the precise debridement of tissue. This method makes it easier and faster for the surgeon to obtain the desired thickness of harvested skin. In addition, by obtaining a smooth surface and an even thickness of harvested donor skin, this technique may lead to improved graft viability.

• Journal of Forest and Environmental Science
• /
• 제35권4호
• /
• pp.232-239
• /
• 2019

This study was carried out to establish an efficient selection condition for cold-tolerant individuals among evergreen Quercus spp. To select higher cold-tolerant individuals among four species of evergreen Quercus spp. (Q. acuta, Q. glauca, Q. myrsinaefoila, and Q. salicina), an-year-old seedlings of each species were exposed to low temperature in serial, and then examined for the death of cell tissue and the surface temperature was monitored. It was shown that the higher numbers of seedlings of Q. myrsinaefolia were survived than the others when those seedlings are exposed to cold stress. Thus, selection of the cold tolerant individuals was conducted on Q. myrsinaefolia seedlings. The limit low temperature condition for selecting cold-tolerant individuals was -6℃ for 24 hrs because no seedling of Q. myrsinaefolia was survived after exposed to -7℃ for 24 hours. It was shown that the leaf surface temperature of the selected individuals was higher than those of the non-selected individuals when they were exposed to cold-stress while monitoring them using thermal graphic camera. The results in this study can be used for expanding afforestation area of tree species of the warm temperate zone for preparation of climate change.

• 대한치과보철학회지
• /
• 제38권3호
• /
• pp.366-374
• /
• 2000

FRC/ceromer system provides the clinician with a durable, flexible, and esthetic alternative to conventional porcelain fused to metal crowns. FRC is the matrix which is silica-coated and embedded in a resin matrix. The ceromer material which is a second generation indirect composite resin contains silanized, microhybrid inorganic fillers embedded in a light-curing organic matrix. FRC/ceromer restoration has a several advantages: better shock absorption, less wear of occluding teeth, translucency, color stability, bonding ability to dental hard tissues, and resiliency. It has versatility of use including inlay, onlay, single crown, and esthetic veneers. With adhesive technique, it can be used for single tooth replacement in forms of inlay adhesion bridge. In single tooth missing case, conventional PFM bridge has been used for esthetic restoration. However, this restoration has several disadvantages such as high cost, potential framework distortion during fabrication, and difficulty in repairing fractures. Inlay adhesion bridge with FRC/ceromer would be a good alternative treatment plan. This article describes a cases restored with Targis/Vectris inlay adhesion bridge. Tooth preparation guide, fabrication procedure, and cementation procedure of this system will be dealt. The strength/weakness of this restoration will be mentioned, also. If it has been used appropriately in carefully selected case, it can satisfy not only dentist's demand of sparing dental hard tissue but also patient's desire of seeking a esthetic restorations with a natural appearance.

• 한국환경보건학회지
• /
• 제34권1호
• /
• pp.49-54
• /
• 2008

The induction of heme oxygenase-1(HO-1) by UV radiation provides a protective defence against oxidative stress, and has been well demonstrated in skin irradiated with UVA, but not UVB. In this study, we show that the induction of cutaneous HO-l can be attributed to UVB radiation. The expression of HO-1 mRNA was assessed in vivo by reverse transcription-polymerase chain reaction (RT-PCR) analysis, and HO-1 enzyme activity was measured in microsomal preparation from irradiated mice. The mRNA level of HO-1 increases in liver and skin from 1d to 3d after UVB $(3KJ/m^2)$ exposure. The results of gene expression were same pattern of HO-1 enzyme activity in skin, but not in liver. HO-1 mRNA in liver resulted in a progressive increase to 4d after UVB exposure, but HO-1 activity in liver increased to 2d. This finding indicates that UVB radiation is an important inducer of HO-1 and increases in HO activity may protect tissue directly or indirectly from oxidative stress.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 1996년도 춘계학술대회
• /
• pp.179-179
• /
• 1996

The involvement of the cyclic AMP (cAMP) effector system in the release of endogenous dopamine and acetylcholine from the rat neostriatum was assessed. Forskolin, an activator of adenylate cyclase, was used to enhance CAMP production, and the consequence of this enhancement on the spontaneous and potassium stimulated release of dopamine and acetylcholine was evaluated. Neostriatal slices were prepared from Fischer 344 rats and after a preincubation period the release of each endogenous neurotransmitter was measured from the same slice preparation. To measure acetylcholine release the slice acetylcholinesterase (AChE) activity was inhibited with physostigmine, but the release from slices with intact AChE activity was also determined (choline, instead of acetylcholine was detected in the medium). Under both conditions forskolin induced a significant dose-dependent increase in the potassium-evoked release of dopamine. In the same tissue preparations the release of neither acetylcholine (AChE inhibited) nor choline (AChE intact) was affected by forskolin. The results indicate that the cAMP second messenger system is involved ill neuronal mechanisms that enhance neuronal dopamine release, but stimulation of this second messenger by forskolin does not further enhance neostriatal acetylcholine release.

• The Korean Journal of Physiology
• /
• 제26권2호
• /
• pp.123-128
• /
• 1992

The present study was undertaken to examine if endogenous nitric oxide is partly responsible for the high calcium induced vasorelaxation in vitro. Isolated porcine coronary arterial rings were suspended in the tissue chamber and their changes in isometric tension were recorded. KCI little affected the vascular tension in the calcium free media, but subsequent addition of cumulative doses of $CaCl_3$ from 1 to 40 mM caused a contraction followed by complete relaxation. The maximum tension was noted at the calcium concentration in the media of 5 mM, and then the tension progressively declined at 10-40 mM. The relaxation was slightly attenuated in the endothelium-denuded preparation. The relaxation was converted into a contraction by the addition of methylene blue. The relaxation response was not affected in the presence of indomethacin, but was significantly attenuated by $N^w-nitro-L-arginine$ methyl ester pretreatment. These results suggest that the calcium induced vasorelaxation is in part attributable to the release of endogenous nitric oxide.