• Molecules and Cells
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• 제38권7호
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• pp.663-668
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• 2015

hBMSCs are multipotent cells that are useful for tissue regeneration to treat degenerative diseases and others for their differentiation ability into chondrocytes, osteoblasts, adipocytes, hepatocytes and neuronal cells. In this study, biodegradable elastic hydrogels consisting of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(${\varepsilon}$-caprolactone) (PCL) scaffolds were evaluated for tissue engineering because of its biocompatibility and the ability to control the release of bioactive peptides. The primary cultured cells from human bone marrow are confirmed as hBMSC by immunohistochemical analysis. Mesenchymal stem cell markers (collagen type I, fibronectin, CD54, $integrin1{\beta}$, and Hu protein) were shown to be positive, while hematopoietic stem cell markers (CD14 and CD45) were shown to be negative. Three different hydrogel scaffolds with different block compositions (PEG:PCL=6:14 and 14:6 by weight) were fabricated using the salt leaching method. The hBMSCs were expanded, seeded on the scaffolds, and cultured up to 8 days under static conditions in Iscove's Modified Dulbecco's Media (IMDM). The growth of MSCs cultured on the hydrogel with PEG/PCL= 6/14 was faster than that of the others. In addition, the morphology of MSCs seemed to be normal and no cytotoxicity was found. The coating of the vascular endothelial growth factor (VEGF) containing scaffold with Matrigel slowed down the release of VEGF in vitro and promoted the angiogenesis when transplanted into BALB/c nude mice. These results suggest that hBMSCs can be supported by a biode gradable hydrogel scaffold for effective cell growth, and enhance the angiogenesis by Matrigel coating.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권6호
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• pp.379-391
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• 2003

The present study was undertaken to evaluate bone regenerative capacity around titanium screw implants placed in irradiated rat's tibiae. At one week after single 15-Gy dose irradiation, miniaturized titanium screw implants were inserted into anterior aspect of the upper tibia of rats weighing 200-250g. Seventy rats were involved: 35 rats were control and 35 rats radiation group. The rats were killed at different intervals as 1, 2, 3, 4, 6, 8, 12 weeks after implantation for histologic observation, histomorphometric analysis and immunohistochemical study with fibronectin and CD34 antibody. 1. Histologically, various stages of bone maturation and ossification can be seen at 4 weeks and regenerated bone close to edges demonstrates more advanced calcification, and network of new bone are well formed at 12 weeks in non-irradiated group. In contrast, active bone formation with increased contact of newly formed bone to implant surface was noted at 4 weeks and a significant amount of new bone formation and bone-implant contact is oberved at 12 weeks in irradiated group. 2. Histomorphometrical analysis confirmed these histologic findings. A significant difference in implant-bone contact and bone density was measured between the control and radiation group. Mean MBD was 62.2% in control group and 27.5% in radiation group, mean MBIC was 86.6% in control group and 47.7% in radiation group, and mean TBIC was 87.3% in control group and 45.6% in radiation group at 12 weeks after implantation. 3. In immunohistochemical study with fibronectin and CD34, radiation reduced hematopoietic progenitor cells severely and disturbed differentiation of osteoblast in bone marrow. The results of this study revealed bone healing capacity around implant after radiation therapy was severely impaired and irradiation reduces the capacity for osseointegration of titanium implants. Many factors including radiation dose, period between radiation and implantation, bone quality, time elapse between first and second surgery, type of prosthetics and hyperbaric oxygen therapy must be considered carefully in postradiation implantation.

• Clinical and Experimental Pediatrics
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• 제48권3호
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• pp.284-291
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• 2005

목 적 : 최근에 개발된 자동화혈구계산기를 이용하여 신속 간편하고 정확하게 IRF과 다양한 RCI 측정이 가능해졌다. 저자들은 정상 소아의 연령군별 RCI와 IRF의 정상치를 구하고, 소아빈혈 중 가장 흔한 원인질환인 철결핍성빈혈과 급성감염성빈혈을 포함한 소아빈혈군에서 RCI와 IRF치를 조사하여 소아빈혈의 조기진단과 철결핍성빈혈과 급성감염성빈혈의 감별진단에 유용한지를 알아보고자 하였다. 방 법 : 소아빈혈환자군 61명(급성감염성빈혈 34명, 철결핍성 빈혈 28명)과 정상대조군 57명을 대상으로 자동화혈구계산기 ADVIA 120을 이용하여 IRF과 CHr, MCVr, CHCMr, RDWr, HDWr 및 CHDWr를 포함한 RCI를 측정 후 대조군과 빈혈군 및 철결핍성빈혈군과 급성감염성빈혈군간의 평균치를 비교 분석하였다. 결 과 : 1) 정상대조군의 각 연령군별 IRF 평균치는 신생아군에서 가장 높았다. 정상대조군의 각 연령군별 RCI의 평균값을 비교해보면 신생아군에서 CHr, MCVr 및 HDWr이 다른 연령군에 비해 높았으나 CHCMr과 RDWr은 연령군별 차이를 보이지 않았다. 2) 빈혈군의 IRF는 정상대조군에 비하여 의미 있게 높았고, CHr과 CHCMr은 빈혈군에서 대조군에 비해 낮게 측정되었다. 그러나 MCVr은 빈혈군과 대조군 사이에 차이를 보이지 않았다. 3) 철결핍성빈혈군의 IRF는 정상대조군에 비하여 의미 있게 높았고, RCI 중 CHr과 CHCMr은 철결핍성빈혈군에서 대조군에 비하여 낮게 측정되었으며, RDWr은 철결핍성빈혈군에서 높았고, MCVr과 HDWr은 두 군간에 차이를 보이지 않았다. 4) 급성감염성빈혈군과 대조군의 IRF와 RCI를 비교해 보면 IRF는 급성감염성빈혈군에서 의미 있게 높았고, RCI 중 CHDWr만 차이를 보였으며, CHr, MCVr, CHCMr, RDWr 및 HDWr은 두 군간에 의의 있는 차이를 보이지 않았다. 5) 철결핍성빈혈군과 급성감염성빈혈군 간에 평균연령, 혈색소치 및 망상적혈구수는 차이가 없었다. IRF은 철결핍성빈혈군에 비하여 급성감염성빈혈군에서 의의 있게 높았고, RCI 중 CHr과 CHCMr은 급성감염성빈혈군에 비하여 철결핍성빈혈군에서 의의 있게 낮았으나, MCVr, RDWr 및 HDWr은 두 군간에 차이를 보이지 않았다. 결 론 : 빈혈의 감별진단에 IRF와 RCI가 매우 유용하리라 생각되며 특히 IRF는 급성감염에 의한 빈혈군에서 증가하는 것으로 보아 급성염증에 의한 골수반응이 있음을 생각할 수 있고, 또한 RCI 중 CHr은 빈혈의 감별진단에 아주 유용하고 특히 철결핍성빈혈군의 초기 진단에 유용하나 이에 대해 더욱 많은 연구가 필요하리라 사료된다.