Comparison of Angiogenic Potential of Human Microvascular Endothelial Cells and Human Umbilical Vein Endothelial Cells

Summary BACKGROUND: Endothelial cells cultured in vitro are commonly used as a model for testing the effects of therapeutic or detrimental agents on endothelium. Cells originating from different vascular beds display, however, a heterogeneity of function and phenotype. Here we compared the production of angiogenic growth factors and the sensitivity to exogenous growth factor stimulation of two popular endothelial cell types. METHODS: Experiments were performed on human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC-1) incubated in optimal conditions for 24–48 h. RESULTS: The profile of the spontaneously produced growth factors differed significantly between the two different cell lines tested. HUVEC did not produce detectable amounts of VEGF, whereas HMEC-1 released 24.9 pg/ml and this amount was significantly increased in response to IL-1. Instead, HUVEC produced high concentrations of soluble form of VEGF receptor-1 (VEGF-R1), whereas the release of VEGF-R1 from HMEC-1 was 10-fold lower. Small amounts of bFGF were found in media from both cell types, but higher levels were detected in HMEC-1 cultures. In contrast, the secretion of interleukin-8 (IL-8) and matrix metalloproteinase-1 (MMP-1) were 30- to 40-fold higher in HUVEC than in HMEC-1. The cell types differed also in their sensitivity to exogenous growth factors. The basal proliferation of HUVEC was very low but could be effectively stimulated by supplementation with VEGF or bFGF. HMEC-1 proliferated spontaneously and their proliferation rate was not further augmented by growth factors. Similarly, the spontaneous outgrowth of capillaries was negligible in HUVEC but well pronounced in HMEC-1. CONCLUSIONS: Production of angiogenic agents and sensitivity to exogenous growth factors is cell-type dependent. HUVEC, which do not release VEGF, can be easily stimulated with exogenous factors, whereas HMEC-1, which are able to produce VEGF, do not respond well to the additional stimulation. Our study demonstrates that conclusions resulting from in vitro experiments performed on only one type of endothelial cells can be misleading.     

Spatial-temporal display of colour-flow ultrasound for the assessment of the effects of intermittent pneumatic compression in limbs

Colour-flow M-mode ultrasonography in three dimensions (two spatial, one temporal) was used to assess the effects of intermittent pneumatic compression on the blood flow velocities in the common femoral vein and artery. The linear array of a standard 3-D system was held in place over the vessels, to record while a calf and thigh cuff compressed to 60 mmHg. The data was reconstructed in 3-D and, subsequently, sliced in different planes. The technique effectively demonstrated the emptying of distal veins during compression, and hyperaemia in the artery on deflation, in the coronal and sagittal planes. Reconstructions of this type may be of use in visualising the distribution of flow changes within blood vessels. (E-mail: morrisrj@cf.ac.uk)     

Comparison of argon-laser welded and sutured repair of inferior vena cava in a canine model

BACKGROUND AND OBJECTIVE: Advantages of laser-welded microarterial anastomoses have been reported. However, whether laser repair of large veins is advantageous is not yet known. Argon-laser welding of inferior vena cava was therefore compared with conventional-sutured repair. STUDY DESIGN/MATERIALS AND METHODS: Twenty-four adult mongrel dogs were used. Twelve inferior vena cavas were repaired using an argon laser and the rest using continuous sutures. Specimens were removed at 2, 8, 16, and 24 weeks after repair. Technical characteristics, cavographical findings, and results of histopathological study using light and transmission electron microscopy were compared. RESULTS: Procedure time did not significantly differ between the two groups. The sutured repair sites were narrower than those repaired by laser immediately after and at 2 and 24 weeks. Histologically, laser welding resulted from denaturation of collagen and mild healing occurred simultaneously with the disappearance of denatured collagen. By contrast, there was strong fibrotic reaction at sutured repair sites. CONCLUSIONS: These findings suggest that argon-laser repair of large veins is superior to continuous suturing.     

Diagnosis of pulmonary embolism

Pulmonary embolism (PE) is a common, lethal yet treatable disease. The clinical diagnosis of PE remains to be a problem due to the nonspecific presenting signs, symptoms, electrocardiographic findings, arterial blood gas abnormalities and chest X-ray changes. Despite these nonspecific clinical findings, clinicians are adept at assigning pretest probability using overall clinical assessment. Clinical models have been developed to improve the accuracy of pretest probability assessment. D-dimers are becoming a widely available clinical tool useful in the diagnostic management of suspected PE. The limitations of the imaging modalities for PE [ventilation–perfusion (V/Q) scanning, spiral computerised tomography, pulmonary angiography and venous leg imaging] necessitate the use of these tests in series and in combination with clinical pretest probability assessment and D-dimer in diagnostic management algorithms. These algorithms permit safe diagnostic management of patients with suspected PE while limiting invasiveness, inaccessibility and expense.     

Nutcracker phenomenon demonstrated by three-dimensional computed tomography

We report a 15-year-old girl with nutcracker syndrome (NCP) in whom three-dimensional helical computed tomography (3D helical CT) was useful for diagnosis; angiographic imaging using 3D helical CT provided fine outlines of the vascular structures in NCP, i.e., a compression of the left renal vein between the aorta and the superior mesenteric artery and the abnormal acute angle between them. Thus, a 3D helical CT enables precise depiction of the anatomical characteristics of renal vasculature and, therefore, may be a useful alternative imaging technique instead of conventional examinations, such as invasive venography or digital subtraction angiography. Further study in a large number of children with vascular abnormalities would be worthwhile. Received: 8 February 2001 / Revised: 10 May 2001 / Accepted: 10 May 2001     

Beware of ‘the vein that easily bleeds’: Accessory right colic vein

In this short article, we highlight the venous drainage of the right colon with special emphasis on the accessory right colic vein. This vein is easily torn during mobilization of the right colon. It is, however, seldom mentioned in the Western anatomy or surgical textbooks.      

Mechanical thrombectomy in patients with deep venous thrombosis

Purpose: To report our experience with mechanical thrombectomy in proximal deep vein thrombosis (DVT). Methods: Eighteen patients with a mean (± SD) age of 37.6 ± 16.1 years who presented with DVT in the iliac and femoral vein (n = 3), inferior vena cava (n = 5), or inferior vena cava and iliac vein (n = 10), were treated with the Amplatz Thrombectomy Device after insertion of a temporary caval filter. Results: Successful recanalization was achieved in 15 of 18 patients (83%). Overall, the percentage of thrombus removed was 66 ± 29%: 73 ± 30% at caval level and 55 ± 36% at iliofemoral level. Complementary interventions (seven patients) were balloon angioplasty (n = 2), angioplasty and stenting (n = 2), thrombo-aspiration alone (n = 1), thrombo-aspiration, balloon angioplasty, and permanent filter (n = 1), and permanent filter alone (n = 1). There was one in-hospital death. Follow-up was obtained at a mean of 29.6 months; three patients had died (two cancers, one myocardial infarction); 10 had no or minimal sequelae; one had post-phlebitic limb. Conclusion: Mechanical thrombectomy is a potential therapeutic option in patients presenting with proximal DVT.     

健侧大隐静脉与股深静脉吻合治疗下肢深静脉栓塞的应用解剖

ObjectiveTo provide anatomical basis for treatment of the deep venous thrombosis of lower limb with deep femoral vein shunting to contralateral great saphenous vein.MethodsThe course,tributaries,valve,anastomosis,length and diameter of the deep femoral vein were observed and measured on 30 sides of adult cadavers.ResultsThe deep formal vein,formed by the perforating venous trunk and tributaries of gracilis muscle,converged into the femoral vein 8.6±0.9 cm below the midpoint of inguinal ligament.Its truck was 2.6±0.5 cm long and 6.9±1.1 mm in diameter.In 29 cases,there was 1 valve proximal to the abouchement of the first perforating vein.The deep femoral vein collected the venous blood of the thigh and the knee,the superficial venous blood of the shank.ConclusionsThe deep femoral vein anastomosis with the contralateral great saphenous vein can remit the swelling and the venous high pressure of the lower limb by shunting the deep femoral venous blood to the contralateral great saphenous vein.     

妊娠高血压综合征患者血浆与羊水和脐静脉血肾上腺髓质素含量变化

目的:探讨ADM在妊娠高血压综合征(妊高征)患者血浆、羊水和脐静脉血中的变化。方法:对50例正常孕妇和59例妊高征患者血浆进行ADM(1-52)测定,并对其中46例正常孕妇和50例妊高征患者取羊水和脐静脉血进行ADM(1-52)测定。结果:妊高征患者血浆ADM(1-52)值(57.39±16.23)ng/L、羊水(57.09±13.39)ng/L和脐静脉血(61.33±18.75)ng/L,均显著高于正常妊娠妇女血浆(18.59±4.79)ng/L、羊水(20.65±8.75)ng/L和脐静脉血(17.34±6.85)ng/L(P均<0.001)。结论:妊高征患者血浆ADM水平高于正常妊娠妇女,提示妊高征患者ADM的代偿性升高具有保护机体、防止血压进一步升高,防止病情恶化。羊水和脐静脉血中保持高水平的ADM,提示胎儿胎盘可能参与ADM的合成和分泌。     

玻璃体腔注射曲安奈德治疗视网膜静脉阻塞黄斑水肿(英文)

目的:比较玻璃体腔注射曲安奈德和传统方法治疗视网膜静脉阻塞黄斑水肿的疗效。方法:共有21例因视网膜静脉阻塞导致黄斑水肿的患者纳入此项临床研究。接受治疗前所有的患者均进行了全面的眼科检查,并随机分为两组。实验组9例患者进行玻璃体腔注射4mg曲安奈德治疗;对照组12例患者接受传统方法治疗。结果:治疗前,对照组视力(logMAR)为1.20±0.38,而实验组为1.64±0.31。治疗后1mo,对照组的视力改善到0.98±0.54(logMAR),而曲安奈德治疗组改善到0.87±0.61(logMAR)。实验组和对照组之间视力改善有显著差异(P<0.01)。结论:研究结果显示,尽管实验组和对照组的患者视力均有改善,但治疗视网膜静脉阻塞黄斑水肿,玻璃体腔注射曲安奈德比传统方法更有效。