Laparoscopy instrument requires blood vessel ligator to prevent blood leakage. Clip ligation device is widely used to prevent blood loss and secure surgical vision by using blood vessel ligator. However, in order to properly install the clip to the vessel ligator and ligate the blood vessel by the ligation machine, the device is properly operated and the parts constituting the jaw areas should be ensuring sufficient strength and rigidity during the operating. Therefore, the clip binding forces were calculated through a dynamic model of the blood vessel ligator. As a result, the force satisfies the target value of 8.5 N or more regardless of the grip force positions. And structural analysis was carried out to find out the maximum resistance force at the tip of the inner shaft. The maximum load was about 45.6 N, which sufficiently satisfies the development target of 40.0 N or higher.

정상 망막을 가진 대상자에서 나타난 망막혈관 형태의 특이 양상을 보고하고자 한다. 안과적 병력이 없고 정상 시력인 22세 여성 대상자의 안저 검사를 실시하였다. 빛간섭 단층촬영 측정결과 망막신경섬유층 두께와 시신경유 두 함몰/시신경유두 직경은 정상이었다. 안저카메라를 이용한 망막혈관 분포의 양상을 확인한 결과 망막중심동맥이 기시하는 시신경유두 부위는 특이 양상은 없었으나 우안의 망막중심동맥이 귀쪽 방향으로 주행 후 상하분지로 나누어지는 현상이 관찰 되었다. 안과적 질환이 없는 정상안에서도 망막중심동맥의 형태를 분류하는 10개의 양상에 포함되지 않는 혈관의 주행이 있을 수 있어 추가적인 확인이 필요할 것으로 사료된다.

Angiography has excellent advantages to visually observe the internal morphology of the stenosed blood vessel. For OCT(Optical coherence tomography), it is possible to directly provide a reliable two-dimensional cross-sectional information as compared to conventional angiography. In the present study, both velocity and wall shear stress distributions were numerically investigated using stenosed blood vessel models (0%, 25%, 50%, and 75% stenotic expansion rate). The blood vessel geometry was prepared based on the human stenotic aorta from OCT image. Commercially available software (CATIA V5) was used to reconstruct 3D blood vessel for numerial analysis. Pulsatile blood flow boundary condition was applied. The numerical study could help our understanding of the hemodynamic differences in a stenosed blood vessel.

본 연구는 50대 비만중년여성을 대상으로 순환운동이 건강체력, 혈압 및 혈관탄성도에 미치는 영향을 규명하는데 있었으며, 이를 위해 비만중년여성 24명을 대상으로 운동그룹 12명, 대조군 12명으로 분류하여 8주간 순환운동 프로그램을 실시하였다. 순환운동 프로그램은 유산소 운동과 저항운동으로 구성 되었으며, 회당 40분간, 주3회 실시하였고, 유산소 운동 수행강도는 50-70% HRmax, 저항운동은 1-RM 의 40-60%로 수행되었으며, 순환운동 전·후에 측정한 자료의 그룹 내 차이 비교를 위해 대응표본 T검정, 그룹 간 차이는 운동 전·후의 변화율을 산출하여 독립표본 T검정을 실시하였다. 그 결과 운동그룹은 건강 체력 중 BMI(p<.05)가 유의하게 감소하였고, 심폐지구력(p<.001), 근지구력(p<.001), 유연성(p<.01)이 증가하였으며, 그룹 간 대조군 보다 심폐지구력, 유연성이 유의하게 증가되었다(p<.01). 수축기 혈압과 이완기 혈압은 운동그룹이 유의하게 감소하였으며(p<.01), 이완기 혈압은 그룹 간 대조군 보다 운동그룹이 유 의하게 감소하였다(p<.05). PWV는 운동그룹이 유의하게 감소하였고(p<.05), 대조군이 유의하게 증가하였으며(p<.01), 그룹 간 대조군 보다 운동군이 유의하게 감소하였다(p<.05). 이상의 결과 비만중년여성의 건강증진 및 비만치료를 위한 순환운동은 건강체력, 혈압 및 혈관탄성도에 긍정적인 영향을 미친 것으로 사료된다.

Heavy metals such as cadmium and mercury are a highly toxic metal that affects a variety of cellular events, such as cell proliferation, differentiation and survival in animals as well as in human. The exposed heavy metals significantly affected the development and health in pubertal period. However, it is not clear how the toxicity of heavy metals in pubertal affects comparing in adults. To determine the effects of heavy metals on pubertal and adults, heavy metals such as cadmium and mercury were exposed to in pubertal and adults mice for 48 and 72h. Results showed that mice exposed to heavy metals for several hours induced overall tissue and organ damage. Especially, blood vessels of the most organ were more increased in adult mice compared to pubertal mice. And for morphologic alteration, secretary organs such as salivary gland and kidney were affected the most. Taken together, exposing to heavy metal in mice altered the blood vessels. In addition, the adverse effects of cadmium and mercury were more severe in adult mouse than puberty mouse. Further study is needed to focus on endothelial cells for more precise its mechanism

In the present numerical study, simple stenotic artery models using pulsatile flow condition were investigated. A reversing sinusoidal velocity for pulsatile flow was imposed at the flow inlet and the corresponding based on the vessel radius. The stenotic geometries modeled using mechanical 3D CAD. It has been used that consist of 0.2, 0.4, 0.5 0.75 and 0.8 stenotic rate in a cylindrical tube. In this paper, numerical solutions are presented for a second harmonic oscillatory flow using commercial code CFX 14. As stenosis rate increases, the maximum wall shear stress(WSS) increases while the minimum WSS decreases. As the stenotic rate increases, the pressure drop at the throat severely decreases to collapse the artery and plaque. It is found that the fluid mechanical disturbances due to the constriction were highly sensitive with rate of stenosis. When stenosis rate increases, the recirculation region exists. In this recirculation region the possibility of plaque attachment is increasingly higher. The present results enhance our understanding of the hemodynamics of a stenotic artery.

동맥경화 상태에서는 혈관이 수축물질에 예민하게 반응 함으로써 혈압의 급격한 변화에 대한 회복능력이 저하한다. 한편 뽕나무 잎에는 고지방식의 섭취로 인해 발생하는 동맥경화증의 발달을 감소시킬 가능성이 있는 여러 물질이 있다고 추정된다. 뽕나무 잎을 백서에 투여하면 고지 방식에 의해 유발된 혈관이 예민해지는 현상을 감소시킬 수 있는지 시험하기 위하여 고지방식 및 뽕나무잎을 8주 간 투여하고 혈관수축 물질에 대한 혈압의 반응성을 시험 하였다. 순환기반사에 따른 혈압반응 감수성차이를 최소화 할 목적으로 동물의 중추신경계를 파괴(pithing)하고 시험 하였다. 고콜레스테롤을 함유한 식이를 공급한 백서에서 교감신경계 전기자극이나 norepinephrine, phenylephrine, angiotensin II 및 vasopressin 등의 투여로 유발된 혈압상승반응이 증강되었으며, 사료에 뽕잎을 2% 또는 10% 첨 가하면 정상적인 혈압상승반응을 보여주었다. 교감신경계를 파괴하지 않은 채 마취만 한 백서에서는 고콜레스테롤에 의한 반응증강이나 뽕잎에 의한 변화를 관찰할 수 없었다. 이 결과로 부터 뽕잎이 동맥경화에서 나타나는 혈관반응성 변화를 방지하는 데 유용한 것으로 판단할 수 있을 것이다.

Endothelial cells are a vital constituent of most mammalian organs and are required to maintain the integrity of these tissues. These cells also play a major role in angiogenesis, inflammatory reactions, and in the regulation of thrombosis. Angiogenesis facilitates pulp formation and produces the vessels which are essential for the maintenance of tooth homeostasis. These vessels can also be used in bone and tissue regeneration, and in surgical procedures to place implants or to remove cancerous tissue. Furthermore, endothelial cell regeneration is the most critical component of the tooth generation process. The aim of the present study was to stimulate endothelial regeneration at a site of acute cyclophosphamide (CP)-induced endothelial injury by treatment with human umbilical cord-derived endothelial/mesenchymal stem cells (hEPCs). We randomly assigned 16 to 20-week-old female NOD/SCID mice into three separate groups, a hEPC (1 × 105 cells) transplanted, 300mg/kg CP treated and saline (control) group. The mice were sacrificed on days 5 and 10 and blood was collected via the abdominal aorta for analysis. The alanine transaminase (ALT), aspartate aminotransferase (AST), serum alkaline phosphatase (s-ALP), and albumin (ALB) levels were then evaluated. Tissue sections from the livers and kidneys were stained with hematoxylin and eosin (HE) for microscopic analysis and were subjected to immunohistochemistry to evaluate any changes in the endothelial layer. CP treatment caused a weight reduction after one day. The kidney/body weight ratio increased in the hEPC treated animals compared with the CP only group at 10 days. Moreover, hEPC treatment resulted in reduced s-ALP, AST, ALT levels compared with the CP only group at 10 days. The CP only animals further showed endothelial injuries at five days which were recovered by hEPC treatment at 10 days. The number of CD31-positive cells was increased by hEPC treatment at both 5 and 10 days. In conclusion, the CP-induced disruption of endothelial cells is recovered by hEPC treatment, indicating that hEPC transplantation has potential benefits in the treatment of endothelial damage.