• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.46-47
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• 2006

Vascularization is essential for success in regenerative medicine. We have developed in vitro models to study how human microvascular endothelial cells (EC) and endothelial progenitor cells (EPC) colonize polymer scaffolds and express the endothelial phenotype, including angiogenesis. Examples are given of supportive growth and differeniation of EC on microfibre meshes of the silk protein fibroin and blends of starch with poly(epsilon-caprolactone), phenotypic markers being studied at both protein and mRNA level. Experimental models are also shown and concepts discussed to investigate how the stem cell niche, including that responsible for vascularization could be targeted, for example, by using engineered biodegradable polymer nanoparticles.

• Applied Microscopy
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• v.52
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• pp.8.1-8.7
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• 2022

The Korean trident goby, Tridentiger brevispinis, lives in adverse habitats that can easily become hypoxic due to low precipitation, regional dry periods, and high amounts of solar radiation. Histological and morphometric studies revealed the goby's specialized skin (35.4-150.0㎛ in thickness), consisting of an epidermis and dermis. The thicker epidermis comprises an outermost surface layer (having taste buds, stratified fattened cells, mucous cells, pigment cells, and stratified polygonal cells), middle layer (having stratified polygonal cells), and stratum germinativum (stratified columnar cells). In particular, the dermis has scales, well-developed vascularization, and a few blood capillaries just above the basement membrane, and a reduced diffusion distance was present in the lateral body. Consequently, adaptations such as thicker epidermis, well-developed vascularization, few blood capillaries, and a reduced diffusion distance may provide cutaneous respiration for survival in poorly oxygenated water during the periodic dry season.

• Archives of Reconstructive Microsurgery
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• v.11 no.2
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• pp.125-134
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• 2002

This study was designed to investigate the process of re- or neo-vascularization in the prefabricated cutaneous flap using a skeletonized arteriovenous pedicle implantation. Fourty-eight flaps were divided into six groups of eight flaps, including control group of the conventional epigastric flap. In experimental groups, skin flap was fabricated by subcutaneous implantation of a distally ligated saphenous arteriovenous pedicle in left abdomen. At 2, 4, 6, 8, and 10 weeks after, prefabricated flap was elevated as an island flap based on implanted pedicle and sutured back in place. Three days after flap repositioning, the area of flap viability was quantified, the pattern of flap vascularization was evaluated with microangiography, and the quantification of vessels was assessed histologically. There were statistically significant differences in flap viability between group 2, 3, 4, and the control (p<0.05), with increased survival area in order. But Group 5 and 6 showed higher flap viability as much as the control did. In the microangiographis study, numerous small meander vessels were newly developed in the vicinity of the implanted pedicle just only 2 weeks after pedicle implantation, but neovascularization around the tip of implanted pedicle, and its anastomosis with native vasculatures was more important for overall flap survival, which was usually developed at least 4 weeks after pedicle implantation. Histologically, vessels are evenly spread over all layers of the flap at 6 weeks after pedicle implantation. The quantification of vessels was correlated well with the improvement of flap viability (p<0.05). In conclusion, neo- and re-vascularization around the tip of implanted pedicle was an important factor for overall survival of the prefabricated flap. Therefore, skeletonized pure vascular pedicle transfer, even though it used alone without surrounding was sufficient to get higher flap viability. The optimal duration of pedicle implantation was8 weeks to obtain maximal survival.

• BMB Reports
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• v.53 no.6
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• pp.291-298
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• 2020

Tumor angiogenesis is an essential process for growth and metastasis of cancer cells as it supplies tumors with oxygen and nutrients. During tumor angiogenesis, many pro-angiogenic factors are secreted by tumor cells to induce their own vascularization via activation of pre-existing host endothelium. However, accumulating evidence suggests that vasculogenic mimicry (VM) is a key alternative mechanism for tumor vascularization when tumors are faced with insufficient supply of oxygen and nutrients. VM is a tumor vascularization mechanism in which tumors create a blood supply system, in contrast to tumor angiogenesis mechanisms that depend on pre-existing host endothelium. VM is closely associated with tumor progression and poor prognosis in many cancers. Therefore, inhibition of VM may be a promising therapeutic strategy and may overcome the limitations of anti-angiogenesis therapy for cancer patients. In this review, we provide an overview of the current anti-angiogenic therapies for ovarian cancer and the current state of knowledge regarding the links between microRNAs and the VM process, with a focus on the mechanism that regulates associated signaling pathways in ovarian cancer. Moreover, we discuss the potential for VM as a therapeutic strategy against ovarian cancer.

• International Journal of Stem Cells
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• v.15 no.1
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• pp.85-94
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• 2022

Background and Objectives: Brain organoids have the potential to improve our understanding of brain development and neurological disease. Despite the importance of brain organoids, the effect of vascularization on brain organoids is largely unknown. The objective of this study is to develop vascularized organoids by assembling vascular spheroids with cerebral organoids. Methods and Results: In this study, vascularized spheroids were generated from non-adherent microwell culture system of human umbilical vein endothelial cells, human dermal fibroblasts and human umbilical cord blood derived mesenchymal stem cells. These vascular spheroids were used for fusion with iPSCs induced cerebral organoids. Immunostaining studies of vascularized organoids demonstrated well organized vascular structures and reduced apoptosis. We showed that the vascularization in cerebral organoids up-regulated the Wnt/β-catenin signaling. Conclusions: We developed vascularized cerebral organoids through assembly of brain organoids with vascular spheroids. This method could not only provide a model to study human cortical development but also represent an opportunity to explore neurological disease.

• The Korean Journal of Nuclear Medicine
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• v.33 no.6
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• pp.475-483
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• 1999

Purpose: Complete fibrovascular ingrowth within the hydroxyapatite ocular implant is necessary for peg drilling which is performed to Prevent infection and to provide motility to the ocular prosthesis. We compared planar bone scintigraphy and SPECT for the evaluation of the vascularization within hydroxyapatite ocular implants. Materials and Methods: Seventeen patients (M:F: 12:5, mean age; $50.4{\pm}17.5$ years) who had received a coralline hydroxyapatite ocular implant after enucleation surgery were enrolled. Patients underwent Tc-99m MDP planar bone and SPECT imaging by dual head gamma camera after their implant surgery (interval: $197{\pm}81$ days). Uptake on planar and SPECT images was graded visually as less than (grade 1), equal to (grade 2), and greater than (grade 3) nasal bridge activity. Quantitative ratio of implanted to non-implanted intraorbital activity was also measured. Vascularization within hydroxyapatite implants was confirmed by slit lamp examination and ocular movement. Results: All but three patients were considered to be vascularized within hydroxyapatite implants. In visual analysis of planar image and SPECT, grade 1 was noted in 9/18 (50%) and 6/18 (33%), respectively. Grade 2 pattern was 7/18 (39%) and 4/18 (22%), and grade 3 pattern was 2/18 (11%) and 8/18 (44%) respectively. When grade 2 or 3 was considered to be positive for vascularization, the sensitivity of planar and SPECT imaging were 60% (9/15) and 80% (12/15), respectively. In 3 patients with incomplete vascularization, both planar and SPECT showed grade 1 uptake The orbital activity ratios on planar imaging were not significantly different between complete and incomplete vascularization ($1.96{\pm}0.87$ vs $1.17{\pm}0.08$, p>0.05), however, it was significantly higher on SPECT in patients with complete vascularization ($8.44{\pm}5.45$ vs $2.20{\pm}0.87$, p<0.05). Conclusion: In the assessment of fibrovascular ingrowth within ocular implants by Tc-99m MDP bone scintigraphy, SPECT image appears to be more effective than planar scintigraphy.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.1
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• pp.11-21
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• 2009

Objectives : This study was performed to investigate the effects of Semen Persicae(SP) on muscle type change and vascularization effect by measuring expression of Myosin heavy chain (MHC) and Vascular endothelial growth factor (VEGF) protein in the Middle cerebral artery occlusion(MCAo) rats. Methods : The middle cerebral artery was occluded, SP extraction was administrated for 4 days. The effects of SP on muscle type change and vascularization were measured. Results : 1. VEGF protein expressions in the Semen Persicae oral administration group of MCAo group were increased compared to the control group. 2. There were no significant difference between the Semen Persicae oral administration of MCAo group and the control group in MHC isoform (Type I, Type IIa) expression change. Conclusions : The present study demonstrates the effect of Semen Persicae in the vascularizing after ischemia, but has no significant effect in musle type change and the improvement of musle atrophy.

• Proceedings of the Zoological Society Korea Conference
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• 2001.04a
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• pp.66.1-66
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• 2001

No Abstract, See Full Text

• Herbal Formula Science
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• v.25 no.2
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• pp.123-134
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• 2017

Wounds are commonly created during almost every kind of surgery, trauma and skin diseases. Delayed wound healing affects a plenty of patients and requires prolonged treatments that seriously reduce the quality of life for patients. Skin damage involving large areas or great severity can lead to disability or even death. Wound healing involves a complicated series of actions, of various tissues and cell lineages, concerning inflammation, migration, proliferation, reepithelialization, and remodeling. Sopung-san is reported to have anti-inflammatory effect and has been used for various skin diseases such as allergic dermatitis and atopic dermatitis. In this study, the hypothesis that oral treatment with Sopung-san could enhances healing potential on rat full thickness skin wounds was tested. Twenty young male Sprague-Dawley rats were used for the studies. A full-thickness skin wound was made on the dorsal skin of the rats. Either Sopung-san water extract (SPS) or saline (Control) was orally administrated every day. The wound area was measured and the percentages of wound contraction, wound healed and wound epithelization were calculated. Wound tissue samples were excised following injection for histopathological and immunohistological examination. Wound area in rats of SPS group significantly was decreased compared to Control. SPS group showed significant promotion of wound healing compared to Cotrol group in the percentages of wound contraction, wound healed and wound epithelization. Histopathological examination revealed that SPS induces neo-vascularization potential in wound healing process. SPS treatment in rats significantly accelerated cutaneous wound healing in the neo-vascularization process by increasing VEGF and $TGF-{\beta}1$ synthesis. The results suggest that Sopung-san affects key cellular processes responsible for wound repair and point to a unique potential for this molecule in the therapy of skin wounds, particularly as an angiogenic agent.

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.157.4-157
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• 2003

No Abstract, See Full Text