• The Korean Journal of Physiology and Pharmacology
• /
• 제19권4호
• /
• pp.335-340
• /
• 2015

Here, we investigated the role of zerumbone, a natural cyclic sesquiterpene of Zingiber zerumbet Smith, on angiogenesis using human umbilical vein endothelial cells (HUVECs). Zerumbone inhibited HUVECs proliferation, migration and tubule formation, as well as angiogenic activity by rat aorta explants. In particular, zerumbone inhibited phosphorylation of vascular endothelial growth factor receptor-2 and fibroblast growth factor receptor-1, which are key regulators of endothelial cell function and angiogenesis. In vivo matrigel plug assay in mice demonstrated significant decrease in vascularization and hemoglobin content in the plugs from zerumbone-treated mice, compared with control mice. Overall, these results suggest that zerumbone inhibits various attributes of angiogenesis, which might contribute to its reported antitumor effects.

• Archives of Plastic Surgery
• /
• 제46권3호
• /
• pp.267-271
• /
• 2019

A 70-year-old man complained imbalance while walking, inability to perform ankle flexion, and could not stand on tip-toe 3 months after injury. The ankle looked swollen with loss of Achilles contour and obvious gait disturbance. Magnetic resonance imaging shows a 5-cm Achilles tendon gap. Subsequently, surgery was performed to solve the neglected Achilles tendon rupture. Patient was put under general anesthesia with a regional block. Using a nontourniquet technique, a reconstructive procedure was performed using a half-width autologous Achilles tendon graft, which was attached to the calcaneal prominence with wire in a double strand Bunnell fashion. As for the proximal stump, double core Bunnell/modified Kessler suturing was carried out to suture the graft to Achilles stump. To increase the vascularization, an ipsilateral gastrocnemius fascial flap with a distally based-pedicle was harvested to wrap around the tendon graft. At a 6-month follow-up, the patient was able to stand on tip-toe and had also regained a normal gait.

• International Journal of Stem Cells
• /
• 제17권1호
• /
• pp.15-29
• /
• 2024

The development and differentiation of endothelial cells (ECs) are fundamental processes with significant implications for both health and disease. ECs, which are found in all organs and blood vessels, play a crucial role in facilitating nutrient and waste exchange and maintaining proper vessel function. Understanding the intricate signaling pathways involved in EC development holds great promise for enhancing vascularization, tissue engineering, and vascular regeneration. Hematopoietic stem cells originating from hemogenic ECs, give rise to diverse immune cell populations, and the interaction between ECs and immune cells is vital for maintaining vascular integrity and regulating immune responses. Dysregulation of vascular development pathways can lead to various diseases, including cancer, where tumor-specific ECs promote tumor growth through angiogenesis. Recent advancements in single-cell genomics and in vivo genetic labeling have shed light on EC development, plasticity, and heterogeneity, uncovering tissue-specific gene expression and crucial signaling pathways. This review explores the potential of ECs in various applications, presenting novel opportunities for advancing vascular medicine and treatment strategies.

• Archives of Reconstructive Microsurgery
• /
• 제6권1호
• /
• pp.9-28
• /
• 1997

Adequate vascularization is pivotally essential for a successful nerve graft. Theoretically, the immediate vascularization will inhibit fibroblast infiltration and stimulate nerve cell regeneration. In this study, histomorphological and electrophysiological studies were performed to determine if vascularized grafts are functionally superior. In rat model, a 4cm segment of the sciatic nerve was obtained and placed as a non vascularized graft on one side, and as a vascularized graft connected to the inferior gluteal vessels on the opposite side. To determine the compound action potential of the gastrocnemius muscle, electromyography was done after 2, 3 and 4 months. Histomorphologically, the distribution of myelinated nerve fibers and Schwann cell were evaluated after toluidine blue staining, The following resutls were obtained: 1. The electrophysiological studies showed no difference between the nonvascularized and vascularized grafts. 2. Two and three months after grafting, myelinated nerve fibers were more abundant in the vascularized proximal, middle and distal areas in all nerve fibers of varying diameters. 3. In the post-nonvascularized graft 2-month group, a few myelinated nerve fibers were present in the proximal and middle areas, but none distally. In the post-vascularized graft 2 month group, myelinated nerve fibers ranging $2-8{\mu}m$ were present in all three areas. 4. In the post-nonvascularized graft 3 month group, a few myelinated nerve fibers ranging in $2-6{\mu}m$ were present in all three areas, but in the post-vascularized graft 3 month group, many myelinated nerve fibers ranging in $2-10{\mu}m$ were present in all three areas. 5. In the post-graft 4-month group, more myelinated nerve fibers were present in all three areas of the vascularized grafts. However, nerve fibers of less than $2{\mu}m$ in diameter were more abundant in the non vascularized grafts. 6. Schwann cells were more abundant in the proximal, middle and distal areas of the post-vascularized 2, 3 and 4-month grafts. Based on these findings, the immediate restoration of circulation in vascularized nerve grafts allows for the increased number of surviving Schwann cells, rapid healing of the axon and myelin sheath changes which occur during Wallerian degeneration, and thus is able to stimulate a morphologically optimal regeneration.

• 대한핵의학회지
• /
• 제29권4호
• /
• pp.518-525
• /
• 1995

목적 : 안구제거술 후에 삽입한 hydroxyapatite 안구보충물내로 혈관신생이 완전하게 일어 나는 시기를 알아보기 위함이다. 방법 : 안구제거술을 받은 43예의 환자(남자 33예, 여자 10예, 14-56세)에게 대부분 변경되지 않은 방법으로 hydroxyapatite 안구보충물을 삽입한 후 10-23주 사이에 다양한 간격(10-12 주 2예, 13-16주 18예, 17-20주 20예, 21-23주 3예)을 두고 $^{99m}Tc-MDP$ 골주사를 시행하여 보충물내로의 혈관신생 정도를 전향적으로 측정하였다. 정면 및 측면촬영의 정적영상에서 안구보충물의 방사능섭취가 비교(nasal bridge)의 방사능섭취보다 약할 경우를 grade 1, 같을 경을 grade 2, 강할 경우를 grade 3로 나누었으며 grade 2와 3을 혈관신생이 완전하다고 정의하였다. 또한 43예 모두에서 방사능섭취 정도와 관계없이 안구보충물 삽입후 평균 21주되는 시기에 안구보충물에 구멍을 내어 이 구멍으로부터의 출혈여부를 확인한 후 운동성나사(motility peg)를 끼워 의안(prosthesis)과 연결하였다. 43예중 7예에서는 $^{99m}Tc-MDP$ 골주사와 조영제주입후의 자기공명영상(Gd-DTPA T1-weighted images)을 같은 날짜에 시행하여 각각의 예에서 방사능섭취 정도와 조영제증강 정도를 비교하였다. 결과 : 안구보충물내로 완전하게 혈관신생이 일어났던 grade 2와 3의 비율은 안구보충물삽입후 10-12주에서는 0%, 13-16주 33%, 17-20주 50%, 21-23주 67%로써 시간경과에 따라 점차 증가하였다. 골주사소견에 관계없이 안구보충물 삽입후 평균 21주되는 시기에 보충물 앞쪽에 구멍을 내었을 때 43예 모두에서 완전한 혈관신생을 의미하는 출혈을 볼 수 있었다. $^{99m}Tc-MDP$ 골주사와 조영제주입후의 자기공명영상을 둘 다 시행한 7예 각각에서 방사능섭취의 정도와 조영제증강의 정도가 거의 일치하였다. 결론 : 본 예비연구의 결과로써 hydroryapatite 안구보충물 삽입후 21주째에 $^{99m}Tc-MDP$ 골주사를 시행하는 것이 좋을 것으로 생각되며, hydroxyapatite 안구보충물내로의 완전한 혈관신생 여부를 보는 데에는 $^{99m}Tc-MDP$ 골주사가 조영제주입후의 자기공명영상보다 더 경제적이라고 할 수 있겠다.

• Imaging Science in Dentistry
• /
• 제50권3호
• /
• pp.199-208
• /
• 2020

Purpose: This study was performed to introduce an in vivo hybrid multimodality technique involving the coregistration of micro-computed tomography (micro-CT) and high-resolution magnetic resonance imaging (HR-MRI) to concomitantly visualize and quantify mineralization and vascularization at follow-up in a rat model. Materials and Methods: Three adult female rats were randomly assigned as test subjects, with 1 rat serving as a control subject. For 20 weeks, the test rats received a weekly intravenous injection of 30 ㎍/kg zoledronic acid, and the control rat was administered a similar dose of normal saline. Bilateral extraction of the lower first and second molars was performed after 10 weeks. All rats were scanned once every 4 weeks with both micro-CT and HR-MRI. Micro-CT and HR-MRI images were registered and fused in the same 3-dimensional region to quantify blood flow velocity and trabecular bone thickness at T0 (baseline), T4 (4 weeks), T8 (8 weeks), T12 (12 weeks), T16 (16 weeks), and T20 (20 weeks). Histological assessment was the gold standard with which the findings were compared. Results: The histomorphometric images at T20 aligned with the HR-MRI findings, with both test and control rats demonstrating reduced trabecular bone vasculature and blood vessel density. The micro-CT findings were also consistent with the histomorphometric changes, which revealed that the test rats had thicker trabecular bone and smaller marrow spaces than the control rat. Conclusion: The combination of micro-CT and HR-MRI may be considered a powerful non-invasive novel technique for the longitudinal quantification of localized mineralization and vascularization.

• International Journal of Vascular Biomedical Engineering
• /
• 제3권1호
• /
• pp.1-5
• /
• 2005

Background: Coronary atherosclerosis artery disease is the leading cause of morbidity and mortality. Coronary artery bypass grafting (CABG) which utilizes the saphenous vein graft, has helped in alleviating the suffering of these patients. Newer techniques are being developed to improve upon the techniques. Still there is significant number of failures, leading to re-grafting or re-vascularization. Some studies have helped in identifying the high and low shear stress regions. Further studies based on their realistic models are required. Material, methods and results: we developed the realistic model of fully blocked right coronary with bypass graft placed at angle of $5^0$ with curvature similar to that of artery. Pulsatile flow of birefringent solution through this model by polarized light was visualized. The images of complete flow field in the model were recorded and analyzed. Regions of high flow disturbances which are prone to further changes are identified. Existence of recirculation in the blocked coronary may initiate new blood-tissue interactions deleterious to bypass graft. Conclusion: Our study shows that by selecting the procedure to place bypass graft at minimum angle with curvature similar to that of artery and smooth sutures may improve the life span of the graft. This study also identified that coronary blocked regions contributing by recirculation flow at the proximal and distal regions of bypass which may require further studies.

• Journal of Periodontal and Implant Science
• /
• 제43권6호
• /
• pp.251-261
• /
• 2013

A paradigm shift is taking place in medicine and dentistry from using synthetic implants and tissue grafts to a tissue engineering approach that uses degradable porous three-dimensional (3D) material hydrogels integrated with cells and bioactive factors to regenerate tissues such as dental bone and other oral tissues. Hydrogels have been established as a biomaterial of choice for many years, as they offer diverse properties that make them ideal in regenerative medicine, including dental applications. Being highly biocompatible and similar to native extracellular matrix, hydrogels have emerged as ideal candidates in the design of 3D scaffolds for tissue regeneration and drug delivery applications. However, precise control over hydrogel properties, such as porosity, pore size, and pore interconnectivity, remains a challenge. Traditional techniques for creating conventional crosslinked polymers have demonstrated limited success in the formation of hydrogels with large pore size, thus limiting cellular infiltration, tissue ingrowth, vascularization, and matrix mineralization (in the case of bone) of tissue-engineered constructs. Emerging technologies have demonstrated the ability to control microarchitectural features in hydrogels such as the creation of large pore size, porosity, and pore interconnectivity, thus allowing the creation of engineered hydrogel scaffolds with a structure and function closely mimicking native tissues. In this review, we explore the various technologies available for the preparation of macroporous scaffolds and their potential applications.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제44권3호
• /
• pp.128-135
• /
• 2018

Objectives: The role of alloplastic materials in maxillofacial reconstruction is still controversial. Determining the utility of porous, high-density, polyethylene implants as a highly stable and flexible, porous alloplast, with properties such as rapid vascularization and tissue ingrowth, is crucial in cases of maxillofacial deformities and aesthetic surgery. Materials and Methods: Thirty high-density porous polyethylene implants were implanted in 16 patients that had been referred to a private office over a three-year period. These implants were used for correcting congenital deformities, posttraumatic defects and improving the aesthetic in nasal, paranasal, malar, chin, mandibular angle, body and orbital areas. Results: The outcomes of the cases in this study showed good aesthetic and functional results. The majority of patients had no signs of discomfort, rejection or exposure. Two implants suffered complications: a complicated malar implant was managed by antibiotic therapy, and an infected mandibular angle implant was removed despite antibiotic therapy. Conclusion: Based on the results, the Medpor implant seems to be an excellent biomaterial for correcting various facial deformities. Advantages include its versatility and relatively ideal pore size that allows for excellent soft tissue ingrowth and coverage. It is strong, flexible and easy to shape.

• Archives of Plastic Surgery
• /
• 제32권3호
• /
• pp.319-326
• /
• 2005

This study was designed to investigate the optimal period of pedicles implantation in the prefabricated periosteofascial flap using a vascular tissue transfer. Flap prefabrication was prepared with a transposition of the central pedicles of right auricle on the calvarium of the New Zealand white rabbit. Thirty flaps were divided into five groups of six flaps, including control group (group I) of the conventional periosteofascial flap based on the right lateral border of parietal bone. The prefabricated flap was elevated as a $2{\times}2cm$ sized island flap and reposed in place in 1, 2, 3, and 4 weeks after the pedicles transfer in groups II, III, IV, and V, respectively. Five days after flap repositioning, the flap viability and vascularity were evaluated with microangiography and histological study quantitatively. The flap survival was increased in accordance with the implanted period of the pedicle. New vessels developed around the implanted pedicle in the 2nd week, and overall vascularization of the flap was accomplished in the 3rd week. The flap with 4 weeks of implantation period, however, showed the same survival rate as the control group. In conclusion, prefabricated periosteo- fascial flap can be created with a vascular tissue transfer, and the optimal duration of the pedicle implantation is more than 4 weeks to obtain adequate flap survival.