scholarly journals From Blood Islands to Blood Vessels: Morphologic Observations and Expression of Key Molecules during Hyaloid Vascular System Development

2012 ◽  
Vol 53 (13) ◽  
pp. 7912 ◽  
Author(s):  
D. Scott McLeod ◽  
Takuya Hasegawa ◽  
Takayuki Baba ◽  
Rhonda Grebe ◽  
Ines Galtier d'Auriac ◽  
...  
Keyword(s):  
Blood Vessels ◽  
Vascular System ◽  
System Development

Microfluidics of blood in blood vessels stenosis

2016 ◽  
Vol 11 (2) ◽  
pp. 210-217 ◽  
Author(s):  
A.T. Akhmetov ◽  
A.A. Valiev ◽  
A.A. Rakhimov ◽  
S.P. Sametov ◽  
R.R. Habibullina
Keyword(s):  
Blood Flow ◽  
Blood Vessels ◽  
Hydraulic Resistance ◽  
Microfluidic Device ◽  
Human Body ◽  
Vascular System ◽  
Hydrodynamic Conditions ◽  
Microstructure Change ◽  
Healthy Part

It is mentioned in the paper that hydrodynamic conditions of a flow in blood vessels with the stenosis are abnormal in relation to the total hemodynamic conditions of blood flow in a vascular system of a human body. A microfluidic device developed with a stepped narrowing for studying of the blood flow at abnormal conditions allowed to reveal blood structure in microchannels simulating the stenosis. Microstructure change is observed during the flow of both native and diluted blood through the narrowing. The study of hemorheological properties allowed us to determine an increasing contribution of the hydraulic resistance of the healthy part of the vessel during the stenosis formation.

Memoirs: Notes on the Structure and the Development of the Elephant's Placenta

1905 ◽  
Vol s2-49 (193) ◽  
pp. 1-38
Author(s):  
RICHARD ASSHETON ◽  
THOMAS G. STEVENS
Keyword(s):  
Blood Vessels ◽  
Vascular System ◽  
Single Layer ◽  
Blood Stream ◽  
Maternal Blood ◽  
Full Term ◽  
Maternal Tissue ◽  
Term Placenta ◽  
Uterine Mucosa ◽  
Foetal Blood

1. The full-term after-birth of the elephant consists of a chorion from which spring many much-branched villi, which spread out in all directions into plate-like branches. These end in (a) proximal foliaceous terminations, in which the fœtal blood vessels ramify, which interlace with a complicated system of much larger blood channels filled with maternal blood, having well-defined but non-nucleated walls; (b) more distal lobate terminations, which are covered by a wellmarked columnar or cubical epithelium -- presumably the trophoblast -- which are partly embedded in a kind of coagulum or detritus, and partly appear to hang loosely in irregular blood spaces without walls ; (c) the stems of still more prolonged villi, which have been torn off and probably left embedded in the walls of the uterus; (d) a few torn ends of blood-vessels. 2. The main trunks of the villi and their foliaceous terminations are everywhere separated from the maternal bloodchannels by a syncytial layer, which is continuous with the epithelium covering the lobate terminations, and is presumably trophoblastic. 3. The half-term placenta originally examined by Owen in 1850 shows, in its more central region, characters which are essentially similar to those of the full-term specimen, and goes far to prove the existence of longer villi which penetrate deeply into the uterine mucosa. The lateral areas of the zonary belt exhibit many most interesting previous conditions. We are able to see in these the simple terminations of the foetal villi covered with a single layer of trophoblast separated from the uterine tissues by a layer of matei'ial partly maternal and partly of foetal origin. There is no process of growth round existing maternal capillaries to form an angio-plasmode, nor apparently any phagocytic action on the part of the trophoblast. The vascularisation of the after-birth is effected by the invasion of the trophoblast by extravasated maternal blood, which flows at first in intercellular and intervillous passages which form the larger channels of the after-birth maternal vascular system, and then makes its way along intra-cellular or intrasyncytial canals through a plasmodium produced by the breaking down of the trophoblast of two adjoining villi. We think the evidence is in favour of considering the corpuscles floating in this invading stream, which contains no red non-nucleated corpuscles in its more advanced portions, to be of maternal rather than trophoblastic origin. 4. The tissues of the full-term placenta contain pigment granules, which are deposited chiefly in the syncytial layer. This we regard as an excretory product; it is almost quite absent from the tissues of the half-term specimen. Leucocytes, either of maternal or foetal origin, seem to be concerned in the transference of this pigment into the maternal blood stream. 5. The subcircular bodies of Owen we find as described by him and Turner, though we note the presence of minute villi on their outer surface. 6. We confirm the opinion of previous writers that the zonary band in part is a "deciduous" form of placenta, although there is not much maternal tissue except the blood. It is not correct to speak of the after-birth being composed of a "much hypertrophied mncosa layer of the uterus." 7. The placenta of the elephant shows by its long villi, which tend to remain embedded in the uterus wall, a resemblance to the condition found in the Sirenia; by the villous patches at the poles and other villi which come out from the uterus, either with or without their trophoblastic covering, but with no maternal cells attached, a resemblance to the ungulata vera of the Perissodactyl type ; by the invasion of the trophoblast--if such it is--by the maternal blood stream, a resemblance to the Discoplacental type, although the actual manner by which this invasion occnrs would seem to be--so far as our very limited material affords us opportunity of observation--unlike anything hitherto described.1 8. The resemblance, at first sight obvious enough to the zonary placenta of the carnivora, is superficial. The elephant's placenta differs from that of the carnivora in (a) consisting of three areas of attachment instead of one, two of which, are wholly in the non-deciduous type, the other partly deciduous, partly non-deciduous. (b) There is nothing formed comparable to an angio-plasmode. (c) The maternal capillaries do not directly become the maternal vessels of the after-birth.

EVALUATION OF THE VESSEL AGE BY APPLYING THE ACCELERATION PLETHYSMOGRAM ANALYSIS

2021 ◽  
pp. 61-67
Author(s):  
Елизавета Александровна Молчанова ◽  
Петр Вячеславович Лужнов
Keyword(s):  
Blood Vessels ◽  
Pulse Wave ◽  
Vascular System ◽  
Vascular Wall ◽  
Second Derivative ◽  
Contour Analysis ◽  
Physiological Factors ◽  
Vascular Age ◽  
Relationship Of ◽  
The Relationship

В работе приведены понятия жесткости, эластичности и тонуса сосудов, а также же их взаимосвязь с общим состоянием сосудистой стенки. Описан индекс, объединяющий влияние вышеперечисленных факторов на состояние сосудистой системы и дающий представление о возрасте сосудов пациента, а также показана связь этого индекса с возрастом человека. Представлен обзор способов определения возраста сосудов с помощью контурного анализа пульсовой волны. Среди предложенных способов был выделен подход на основе контурного анализа сигнала пульсовой волны, а также ее второй производной. В данном исследовании проводилась разработка алгоритма расчета показателя возраста сосудов (VA), базирующаяся на анализе сигнала и его второй производной. При этом особое внимание уделялось физической интерпретации параметров, входящих в состав расчетной формулы. С помощью представленного алгоритма в группе из трех испытуемых был определен сосудистый возраст. Из анализа полученных результатов было выявлено влияние физиологических факторов на значение возраста сосудов. Предложены методики, позволяющие исключить влияние этих факторов на значения показателя VA и тем самым получить более точные результаты. Также представлены стратегии дальнейшего развития исследований в этом направлении In The paper presents the concepts of rigidity, elasticity and tone of blood vessels, as well as their relationship with the general state of the vascular wall. An index is described that combines the influence of the above factors on the state of the vascular system and gives an idea of the age of the patient's vessels, and also shows the relationship of this index with the age of a person. An overview of the methods for determining the age of blood vessels using the contour analysis of the pulse wave is presented. Among the proposed methods, an approach based on the contour analysis of the pulse wave signal, as well as its second derivative, was singled out. In this study, an algorithm was developed for calculating the indicator of vascular age (VA), based on the analysis of the signal and its second derivative. In this case, special attention was paid to the physical interpretation of the parameters included in the calculation formula. Using the presented algorithm, vascular age was determined in a group of three subjects. From the analysis of the results obtained, the influence of physiological factors on the value of the age of the vessels was revealed. Methods are proposed that allow to exclude the influence of these factors on the values of the VA indicator and thereby obtain more accurate results. Also presented are strategies for the further development of research in this direction

Digital motion analysis as a tool for analysing the shape and performance of the circulatory system in transparent animals

2000 ◽  
Vol 203 (11) ◽  
pp. 1659-1669 ◽  
Author(s):  
T. Schwerte ◽  
B. Pelster
Keyword(s):  
Blood Vessels ◽  
Fluorescent Probe ◽  
Motion Analysis ◽  
Vascular System ◽  
Circulatory System ◽  
Cardiac Activity ◽  
Video Frame ◽  
Peripheral Blood Flow ◽  
Gray Scale ◽  
And Performance

The analysis of perfusion parameters using the frame-to-frame technique and the observation of small blood vessels in transparent animals using video microscopy can be tedious and very difficult because of the poor contrast of the images. Injection of a fluorescent probe (fluorescein isothiocynate, FITC) bound to a high-molecular-mass dextran improved the visibility of blood vessels, but the gray-scale histogram showed blurring at the edges of the vessels. Furthermore, injection of the fluorescent probe into the ventricle of small zebrafish (Danio rerio) embryos (body mass approximately 1 mg) often resulted in reduced cardiac activity. Digital motion analysis, however, proved to be a very effective tool for analysing the shape and performance of the circulatory system in transparent animals and tissues. By subtracting the two fields of a video frame (the odd and the even frame), any movement that occurred within the 20 ms necessary for the acquisition of one field could be visualised. The length of the shifting vector generated by this subtraction, represented a direct measure of the velocity of a moving particle, i.e. an erythrocyte in the vascular system. By accumulating shifting vectors generated from several consecutive video frames, a complete trace of the routes over which erythrocytes moved could be obtained. Thus, a cast of the vascular system, except for those tiny vessels that are not entered by erythrocytes, could be obtained. Because the gray-scale value of any given pixel or any given group of pixels increased with the number of erythrocytes passing it, digital motion analysis could also be used to visualise the distribution of blood cells in transparent tissues. This method was used to describe the development of the peripheral vascular system in zebrafish larvae up to 8 days post-fertilisation. At this stage, food intake resulted in a clear redistribution of blood between muscle tissue and the gut, and alpha-adrenergic control of peripheral blood flow was established.

Growth regulation of the vascular system: evidence for a metabolic hypothesis

1990 ◽  
Vol 259 (3) ◽  
pp. R393-R404 ◽  
Author(s):  
T. H. Adair ◽  
W. J. Gay ◽  
J. P. Montani
Keyword(s):  
Blood Flow ◽  
Blood Vessels ◽  
Growth Regulation ◽  
Vascular System ◽  
Major Influence ◽  
Control Element ◽  
Hypoxic Conditions ◽  
Control Growth ◽  
Vessel Growth ◽  
Tissue Cells

Prolonged imbalances between the perfusion capabilities of the blood vessels and the metabolic requirements of the tissue cells often lead to modification of the vasculature to satisfy the tissue needs. This homeostatic response appears to be bidirectional, since the vascularity of a tissue can increase or decrease in parallel with primary changes in metabolic rate. The factors that mediate the responses are not well understood, but oxygen has been implicated as a major control element, since vessel growth increases during hypoxic conditions and decreases during hyperoxic conditions. The following feedback control hypothesis may apply to many different physiological situations. Decreased oxygenation causes the tissues to become hypoxic, and this initiates a variety of signals that lead to the growth of blood vessels. The increase in vascularity promotes oxygen delivery to the tissue cells by decreasing diffusion distances, increasing capillary surface area, and increasing the maximum rate of blood flow. When the tissues receive adequate amounts of oxygen even during periods of peak activity, the intermediate effectors return to normal levels, and this negative signal, in turn, stops the further development of the vasculature. Although the effector mechanisms of the hypoxic stimulus are still being investigated, adenosine, which is produced in hypoxic tissues, appears to mediate hypoxia-induced increases in vascularity in some instances. Roles for fibroblast growth factor as well as mechanical factors associated with vasodilation and increased blood flow are postulated. Although blood vessel growth is a multifactorial process, a major influence in its regulation appears to be metabolic need. If this view is correct, it may be found that many of the quantitatively significant factors that control growth in a given vasculature are themselves modulated or controlled by metabolic signals reflecting the nutritional status of the tissues which that vasculature supplies.

ANGIOMATOSIS (HAMARTOMATOUS HEM-LYMPHANGIOMATOSIS)

PEDIATRICS ◽  
1961 ◽  
Vol 28 (1) ◽  
pp. 65-76
Author(s):  
Peter J. Koblenzer ◽  
Martin J. Bukowski
Keyword(s):  
Blood Vessels ◽  
Lymphatic System ◽  
Vascular System ◽  
Clinical Manifestations ◽  
Body Cavity ◽  
Histologic Examination ◽  
Peripheral Vascular ◽  
Osteolytic Lesions ◽  
System A

A case is described of a diffuse, possibly generalized, abnormality of a hamartomatous nature of the peripheral vascular system. A number of cases from the literature, which also appear to belong in this category, are summarized. Histologic examination shows that lymph and blood vessels may both be involved, though this may be essentially an abnormality of the lymphatic system in which extensive venolymphatic communications occur. The clinical manifestations vary according to the site of involvement and the extent of dissemination and also according to whether the lesions are predominantly hemangiomatous or lymphangiomatous. The main features are osteolytic lesions, visceromegaly, cutaneous hemangiomas or lymphangiomas and massive effusions into any body cavity. The effusions are usually chylous, sanguineous or a mixture of both. Any or all of these features may be present in any one case. The disease frequently has its onset in childhood or adolescence and tends to be progressive. If the lesions are widely disseminated or an effusion into a body cavity is present the outlook is grave. Treatment so far has been unsuccessful. Surgery may occasionally have a place. The term angiomatosis is employed to denote this condition not only to underline its potentially extensive nature but also to avoid debate as to whether it is essentially hemangiomatosis or lymphangiomatosis.

scholarly journals Systemically Administered, Target-Specific, Multi-Functional Therapeutic Recombinant Proteins in Regenerative Medicine

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 226 ◽  
Author(s):  
Tero A.H. Järvinen ◽  
Toini Pemmari
Keyword(s):  
Regenerative Medicine ◽  
Blood Vessels ◽  
Recombinant Proteins ◽  
Clinical Medicine ◽  
Vascular System ◽  
Therapeutic Potential ◽  
Systemic Administration ◽  
Molecular Signature ◽  
Postal Code ◽  
Organ Specific

Growth factors, chemokines and cytokines guide tissue regeneration after injuries. However, their applications as recombinant proteins are almost non-existent due to the difficulty of maintaining their bioactivity in the protease-rich milieu of injured tissues in humans. Safety concerns have ruled out their systemic administration. The vascular system provides a natural platform for circumvent the limitations of the local delivery of protein-based therapeutics. Tissue selectivity in drug accumulation can be obtained as organ-specific molecular signatures exist in the blood vessels in each tissue, essentially forming a postal code system (“vascular zip codes”) within the vasculature. These target-specific “vascular zip codes” can be exploited in regenerative medicine as the angiogenic blood vessels in the regenerating tissues have a unique molecular signature. The identification of vascular homing peptides capable of finding these unique “vascular zip codes” after their systemic administration provides an appealing opportunity for the target-specific delivery of therapeutics to tissue injuries. Therapeutic proteins can be “packaged” together with homing peptides by expressing them as multi-functional recombinant proteins. These multi-functional recombinant proteins provide an example how molecular engineering gives to a compound an ability to home to regenerating tissue and enhance its therapeutic potential. Regenerative medicine has been dominated by the locally applied therapeutic approaches despite these therapies are not moving to clinical medicine with success. There might be a time to change the paradigm towards systemically administered, target organ-specific therapeutic molecules in future drug discovery and development for regenerative medicine.

Gene Trap, Gene Knockout, Gene Knock-In, and Transgenics in Vascular Development

1999 ◽  
Vol 82 (08) ◽  
pp. 865-869 ◽  
Author(s):  
Thomas Sato
Keyword(s):  
Animal Models ◽  
Molecular Mechanisms ◽  
Vascular System ◽  
System Development ◽  
Gene Knockout ◽  
Vascular Development ◽  
Branching Morphogenesis ◽  
Abnormal Development ◽  
Organ Systems ◽  
Almost All

IntroductionThe vascular system is one of the first organ systems to develop in our bodies. Normal development and maturation of the physiological functions of almost all of the other organs are critically dependent on the accurate and tightly controlled establishment of the vascular system. Our understanding of the mechanisms underlying the formation of the vascular system during development is still in its infancy. With further understanding of these mechanisms, we may eventually be able to correct the abnormal development and the malfunctioning of many organs by therapeutically modulating the morphology and/or physiological function of the vascular system.Our further understanding of the vascular development can, in part, be achieved by discovering the molecules that play critical roles in this process. We could also achieve this goal by learning more about the functions of previously identified molecules in the vascular system. Discovery of new processes underlying the development of the vascular system will also contribute to further understanding of these molecular mechanisms.Recent advances, using the whole genome approach, have resulted in a flood of new information. This trend will continue, and fortunately, a number of molecular reagents will become available. Therefore, the field will likely experience an exponential growth in terms of novel biological insights and discovering the mechanisms of vascular system development.Occasionally, reductionistic approaches help to systematically address a number of biological problems, including the problems associated with vascular system development. One such approach is to choose an organism that allows us to systematically address these biological questions. The choice of animal models that are well-suited for the study of a particular question has led to a large number of discoveries. To address questions in vascular system development, current research has focused on animal models, including fish, frog, bird, and mouse, and also studies involving humans. It is also worthwhile to note that the branching morphogenesis of the fly trachea system has been utilized to address fundamental questions of vascular morphogenesis.This chapter will summarize the genomic manipulation of the murine vascular system to address questions regarding vascular development. In addition, the advances that have been made in this field using such methods will be summarized.

scholarly journals The sialomucin CD34 is expressed on hematopoietic cells and blood vessels during murine development

Blood ◽  
1995 ◽  
Vol 85 (1) ◽  
pp. 96-105 ◽  
Author(s):  
PE Young ◽  
S Baumhueter ◽  
LA Lasky
Keyword(s):  
Blood Vessels ◽  
Matrix Protein ◽  
Vascular System ◽  
Fetal Liver ◽  
Hematopoietic Cells ◽  
Embryoid Bodies ◽  
Extracellular Matrix Protein ◽  
Hematopoietic Stem ◽  
Endothelial Growth Factor ◽  
High Degree

The processes of angiogenesis and hematopoiesis require a high degree of coordination during embryogenesis. Whereas much is understood about the development of the vascular system in avian embryos, little information has been attained in mammals, predominantly because there are no specific markers for either blood vessels or hematopoietic cells in any developing mammalian system. We have recently shown that murine CD34 (mCD34) is expressed on the vascular endothelium in all organs and tissues of the adult mouse as well as on a small percentage of presumably hematopoietic stem cells in the bone marrow and fetal liver. Here we show that mCD34 is also expressed on the endothelium of blood vessels and on a subset of hematopoietic-like cells throughout murine development. mCD34 is first observed on the yolk sac endothelium of day 7.5 embryos and on a subset of hematopoietic cells within these yolk sacs. mCD34 expression is maintained on vessels and hematopoietic cells in all organs and tissues throughout embryogenesis. In addition, mCD34 is localized on growth conelike filopodial processes that appear at the budding edge of newly sprouted capillaries. Double staining of capillaries for mCD34 and laminin shows that these growth conelike processes seem to be free of laminin, whereas the formed capillaries seem to be coated with this extracellular matrix protein. Analysis of vessels in developing brain shows that these filopodial processes seem to be directed toward the ventricular epithelium, a previously described site of vascular endothelial growth factor synthesis. Finally, we show that the vascular structures of developing murine embryoid bodies also express mCD34. These data suggest that mCD34 is a useful marker for the analysis of the development of the blood vascular system in murine embryos.

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