Focal or diffuse dilatation of pelvic vessels is observed occasionally on computed tomographic or magnetic resonance images. Two major mechanisms may account for dilatation. The first mechanism is development of collateral channels as a result of venous obstruction or stenosis. Symptoms associated with vessel dilatation vary according to the level ...

In this report, we describe a novel in vitro perfused microvessel model for training microvascular anastomotic exercises. Arteries and veins with a diameter of ca. 1 mm were explanted from chicken wings. These vessels were cannulated at both ends and mounted on a platform. Preserved, expired whole blood obtained from ...

The influence of He-Ne laser radiation on the formation of new blood vessels in the bone marrow compartment of a regenerating area of the mid-cortical diaphysis of the tibiae of young adult rats was studied. A small hole was surgically made with a dentistry burr in the tibia and the ...

Endometria from long term progestin only contraceptive-treated patients display abnormally enlarged blood vessels that are prone to bleeding as well as inflammation and possibly local diminution in blood flow. Such bleeding is also characterized by focal reductions in the expression of angiopoietin-1, a vessel stabilization and maturation agent, and excess ...

The engineering of biological substitutes and strategies for the replacement and/or repair of blood vessels and the components of the heart represents an important challenge for tissue engineering. In this review, the progress to date and the barriers remaining are addressed. Even though the progress has been considerable and there ...

The reproducible pattern of blood vessels formed in vertebrate embryos has been described extensively, but only recently have we obtained the genetic and molecular tools to address the mechanisms underlying these processes. This review describes our current knowledge regarding vascular patterning around the vertebrate midline and presents data derived from ...

BACKGROUND AND PURPOSE: Although vertebral artery (VA) blood flow is adequate in normal circumstances, reduction in the dimensions of the vessel because of atherosclerosis, or compression or stretching, may lead to hindbrain hypoxia with serious clinical manifestations. Such effects may be more pronounced in VAs that are naturally smaller than ...

Ablative therapies such as radio-frequency (RF) ablation are increasingly used for treatment of tumours in liver and other organs. Often large vessels limit the extent of the thermal lesion, and cancer cells close to the vessel survive resulting in local tumour recurrence. Accurate estimates of the heat convection coefficient h ...

Postnatal neovascularization is essential for wound healing, cancer progression, and many other physiological functions. However, its genetic mechanism is largely unknown. In this report, we study neovascularization in regenerating adult zebrafish fins using transgenic fish that express EGFP in blood vessel endothelial cells. We first describe the morphogenesis of regenerating ...

In the field of arterial vascular reconstructions there is an increasing need for functional small-diameter artificial grafts (inner diameter < 6mm). When autologous replacement vessels are not available, for example because of the bad condition of the vascular system in the patient, the surgeon has no other alternative than to ...

BACKGROUND: There is some evidence that the epithelial cell rests of Malassez partition the root surface from the periodontal ligament blood vessels, and may protect the root from resorption. OBJECTIVE: The aim of the present study was to determine the distributions of the epithelial rests of Malassez (ERM) and blood ...

A new coefficient of elasticity is proposed that relates to the elastic state of the blood vessels. This measure is proposed as a result of the realization, from personal experience as well as from the international literature, of the difficulty in measuring the thickness of the blood vessels in vivo ...

Regulation of blood vessels is intrinsically tied to inflammatory signaling. Recent research suggests that chronic inflammation is associated with atherosclerosis risk. The antiphospholipid syndrome is a prototypic autoimmune disease. Disturbance of blood vessel homeostasis in this disorder may increase risk for atherosclerosis by mechanisms that are direct (through antibody targeting ...

Inadequate vascular perfusion leads to fatal heart attacks, chronic ulcers, and other serious clinical conditions. The body's capacity to restore vascular perfusion through angiogenesis and arteriogenesis is often impaired by pre-existing disease, and availability of native replacements for nonfunctional arteries is limited in many patients. Thus, recreating blood vessels of ...

To test the hypothesis that the distribution of the pathology in variant Creutzfeldt-Jakob disease (vCJD) represents haematogenous spread of the disease, we studied the spatial correlation between the vacuolation, prion protein (PrP) deposits, and the blood vessel profiles in the cerebral cortex, hippocampus, dentate gyrus, and cerebellum of 11 cases ...

We have used time-lapse multiphoton microscopy of living Tg(fli1:EGFP)y1 zebrafish embryos to examine how a patterned, functional network of angiogenic blood vessels is generated in the early vertebrate trunk. Angiogenic vascular sprouts emerge from the longitudinal trunk axial vessels (the dorsal aorta and posterior cardinal vein) in two spatially and ...

The past decade has seen considerable advances in the understanding of angiogenesis. Blood vessel development and growth in the central nervous system are tightly controlled processes that are regulated by angiogenic factors. Angiogenic factors have been implicated in the pathogenesis of a wide variety of disorders, including primary and metastatic ...

Background/Purpose. Recent findings suggest that an objective assessment of retinal vessel caliber from fundus photographs provide information about the association of microvascular characteristics with macrovascular disease. Current methods used to quantify retinal vessel caliber, introduced by Parr(1,2) and Hubbard,(3) are not independent of scale and are affected by the number ...

We evaluated the distances and angles of the major blood vessels from various pelvic structures in the plane of the tension-free vaginal tape (TVT) procedure in 19 pelvic MR imagies. The major blood vessels were the iliofemoral vessels. The mean distance of the left iliofemoral vessels from the midline was ...

Microsurgery has revolutionized the art of reconstruction, with the discovery of the ability to replace like tissue with like tissue transferred from a distant site. The evolution of the tissue transferred has also progressed. No longer are free flaps based off a dominant anatomically named vessel, but one of its ...

CADASIL (Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is a type of small-artery stroke and vascular dementia-inducing pathology of the brain. In order to explain the molecular mechanisms behind the alterations to the blood vessels in CADASIL subjects, we scrutinized the expression of glycan and glycan-binding sites in ...

In the developing chondroepiphyses of long bones, the avascular cartilaginous anlage is invaded by numerous blood vessels, through the process of angiogenesis. The objective of this study was to investigate the chronology of this vascular invasion with the spontaneous calcification of the cartilaginous epiphysis during development of the secondary ossification ...

Two-photon excitation photodynamic therapy (TPE-PDT) is being investigated as a clinical treatment for age-related macular degeneration (AMD). TPE-PDT has the potential to provide a more specific and therefore advantageous therapy regime than traditional one-photon excitation PDT. The highly vascularized 8 to 9-day-old chicken chorioallantoic membrane (CAM) is used to model ...

PURPOSE: To determine the efficacy of photodynamic therapy (PDT) with verteporfin (Visudyne; Novartis AG, Basel, Switzerland) for treatment of corneal neovascularization in a rabbit eye model. METHODS: Corneal neovascularization was induced in Dutch belted rabbits by placing an intrastromal silk suture near the limbus. Verteporfin was administered by intravenous injection ...

PURPOSE: Looping patterns rich in laminin are present in tissue samples of primary aggressive human uveal melanomas and their metastases. Because these extravascular patterns connect to blood vessels and transmit fluid in vitro and in vivo, the three-dimensional configuration of these patterns has been the subject of considerable speculation. In ...

Measurements of the relative Doppler power scattered by an embolus and the surrounding blood are widely used to infer the composition of the embolus. For a given embolus, measured embolus-to-blood ratio (MEBR) is affected by the Doppler sample volume shape, the geometrical relationship between the sample volume and the vessel, ...

Angiogenic cytokines such as vascular endothelial growth factor-A(164/165) (VEGF-A(164/165)) and placenta growth factor (PlGF) are being considered for therapeutic relief of coronary heart disease and other forms of tissue ischemia caused by atherosclerosis. Before proceeding further with clinical testing, it is important to determine what types of new blood vessels ...

INTRODUCTION: The aim of this study is to examine the structure and vascularization of the acetabular labrum with regard to the pathogenesis and healing of labral tears. MATERIALS AND METHODS: The labral tissue was characterized immunohistochemically and under light microscopy; the collagen fibril texture was demonstrated by scanning electron microscopy ...

Blood vessels constitute the first organ in the embryo and form the largest network in our body but, sadly, are also often deadly. When dysregulated, the formation of new blood vessels contributes to numerous malignant, ischemic, inflammatory, infectious and immune disorders. Molecular insights into these processes are being generated at ...

Blood vessel growth after birth is limited to two major processes. Angiogenesis is the growth of new capillaries by sprouting or intussusception. The major stimulus for angiogenesis is ischemia. In contrast, arteriogenesis describes the remodeling and growth of collateral arteries from a preexisting arteriolar network. Arteriogenesis is induced after the ...

The cornea is an avascular structure whose closest point of approach to the systemic blood stream is provided by the limbal vessels. Activity within these structures provides the clinician with a sensitive indicator of contact lens performance and associated problems. In this paper, the anatomy and physiology of the limbal ...

BACKGROUND: Irregular bleeding affects up to 60% of hormone replacement therapy (HRT) users. The mechanism of this bleeding is not understood. Reduced endometrial microvascular integrity appears to underlie breakthrough bleeding in pre-menopausal women and the aim of this study was to establish whether similar changes are seen in HRT users ...

Optical tissue clearing by hyperosmotic chemical agents significantly increases light depth penetration in skin and may improve light-based therapeutics such as laser treatment of cutaneous vascular lesions. A feasibility study was conducted to evaluate the potential role of optical clearing by glycerol in laser treatment of cutaneous vessels. Optical imaging ...

PURPOSE: The authors propose to validate an angiographic scoring system that estimates the resting blood flow in the lower extremities in patients with peripheral vascular disease (PVD). MATERIALS AND METHODS: Twenty patients with PVD underwent lower-extremity angiography. For each patient, three readers used the proposed scheme to estimate flow within ...

Prolactin (PRL) is a pituitary hormone involved in a broad spectrum of physiological processes, including lactation, development, and immune function. To further investigate the in vivo roles of PRL, rat PRL cDNA, fused to the cytomegalovirus promoter, was introduced into mouse muscle by direct injection. Prolactin mRNA and protein were ...

OBJECTIVE: The aim of this study was to investigate the direct effect of erythropoietin on human placental vessels. STUDY DESIGN: Placental vessel rings (n = 8 for each group) from uncomplicated pregnancies were exposed to recombinant human erythropoietin (10-300 IU/mL) in an isometric myograph. One-way analysis of variance with the ...

Human cerebral blood vessels are frequently damaged in head impact, whether accidental or deliberate, resulting in intracranial bleeding. Additionally, the vasculature constitutes the support structure for the brain and, hence, plays a key role in the cranial load response. Quantification of its mechanical behavior, including limiting loads, is thus required ...

Vascular endothelial growth factor (VEGF) induces increased vessel permeability and formation of abnormal vessels. To investigate cerebral blood flow (CBF) during local overexpression of VEGF recombinant adenoviruses carrying the human VEGF165 complementary DNA (2.3 to 23. 108 pfu/mL) were injected stereotactically into the caudate nucleus of anesthetized rats. Saline and ...

The rat tail vascularization is histologically re-examined especially with respect to blood sampling and vascular-injection methods. The terminal third of the tail is recommended for blood vessel puncturing. In this segment, the arteries and veins are most prominent, since the structures of the musculo-skeletal system diminish towards the tip of ...

PURPOSE: Only sparse data are available on the blood supply of the hypospadiac prepuce. We investigated the development and course of the preputial blood vessels, and applied the results of this study to surgery for hypospadias. MATERIALS AND METHODS: In 157 patients who underwent hypospadias surgery from October 1996 to ...

BACKGROUND: To investigate the vasoactive effect of bimatoprost (Lumigan), a new topical ocular hypotensive agent, in isolated porcine ciliary arteries. MATERIAL AND METHODS: Arteries were placed in a myograph system to measure isometric forces. Quiescent vessels as well as vessels pre-contracted with either 10 nM endothelin-1 or 100 mM potassium ...

Fat necrosis is a common postoperative complication in transverse rectus abdominis muscle flap breast reconstruction. A histological quantification of the blood supply to the lower abdominal fat was undertaken to define this problem further. One hundred eighty sections, 1.5 cm(2) in size, were studied from one half of the lower ...

The microvascular architecture of the human cerebral subcortical white matter was studied. Most of the subcortical arteries ran straight through the cortex, but upon entering the white matter, they began to coil, loop, and spiral. Vascular stains showed wide spaces between the adventitial sheaths and blood vessels. The blood vessels ...

We examine the influence of vessel distensibility on the fraction of the total network flow passing through each vessel of a model vascular network. An exact computational methodology is developed yielding an analytic proof. For a class of structurally heterogeneous asymmetric vascular networks, if all the individual vessels share a ...

BACKGROUND/AIM: During angiogenesis-that is, the outgrowth of new from pre-existing blood vessels, new capillaries undergo a period of "fine tuning" when vascular endothelial cells become apoptotic if sufficient supply of angiogenic factors is lacking. Morphologically, this period correlates with the absence of pericyte coverage of new vessels. Mature, pericyte covered ...

The effect of peroxynitrite on the development of atherosclerosis is one of the major foci of recent studies. Here, the cytotoxic effect of peroxynitrite was investigated by quantitatively measuring nitrated tyrosine, 3-nitrotyrosine (3-NT) levels in atherosclerotic blood vessels. Atherosclerotic vessels were obtained from the patients who underwent either coronary artery ...

Diseases of small cerebral blood vessels are heterogeneous in etiology and manifestations. Lipohyalinosis, venous collagenosis, amyloid angiopathy, and CADASIL affect different populations of blood vessels. Large and small hemorrhages, lacunae, cortical microinfarcts, and leukoaraiosis are the most important consequences of the small vessel angiopathies. Altered permeability as well as ischemia ...

Relatively little attention has been given to vessel wall mechanics in interaction with the pulsatile fluid motion of blood in the epicardial coronary arteries which are prone to atherosclerotic plaque development. Theories for lipid transport by convective effects, while appealing in many ways, do not serve to explain the predominantly ...

Cerebral small-vessel alterations play a central role in determining lesions of subcortical structures and eventually may lead to cognitive impairment. Small-vessel diseases are classified according to the pathological viewpoint. The most important ones are the changes in small arteries and arterioles caused by prolonged hypertension. These small-vessel changes may result ...

The notion that blood vessel lumina and primordial blood plasma are linked by a single mechanism, intracellular vacuolation of angioblasts, has, for the most part, been overlooked since it was first described in the early decades of the last century. That vacuolation may play a major role in blood vessel ...