The Vascular Structure of the Kidney of Mallards and Doves

1999 ◽  
Vol 5 (S2) ◽  
pp. 1192-1193
Author(s):  
H. Ditrich
Keyword(s):  
Vascular System ◽  
Venous Drainage ◽  
Portal System ◽  
Physiological Data ◽  
Vascular Structure ◽  
Serial Sections ◽  
Functional Importance ◽  
Additional Material ◽  
Functional Studies ◽  
Primitive Feature

The architecture of the kidney of birds (and also reptiles) is, unlike in mammalians, mainly determined by the organization of the blood vascular system. Besides arterial supply and venous drainage, the renal portal system forms a main structural component. While the latter was often regarded as a “primitive” feature in the literature, morphological and physiological data reveal its great functional importance.Microvascular corrosion casts studied in the scanning electron microscope permit the visualization of minute vessels, retaining their 3D-arrangement. Additionally, when compared with graphical reconstructions of serial sections, this method avoids several inherent artifacts like fixation and dehydration shrinkage as well as the compression of the object by the sectioning blade. Most of the studies on avian kidneys with this technique used the domestic chicken as a model. In order to provide additional material for comparative and functional studies, data on the intrarenal vascular structure of other species are required.

Lasertechniques treatment of vascular malformations

Phlebologie ◽  
2010 ◽  
Vol 39 (03) ◽  
pp. 167-175
Author(s):  
M. Poetke ◽  
P. Urban ◽  
H.-P. Berlien
Keyword(s):  
Endothelial Cells ◽  
Spontaneous Regression ◽  
Vascular System ◽  
Vascular Malformations ◽  
Clinical Importance ◽  
Vascular Structure ◽  
Laser Application ◽  
Vascular Morphogenesis ◽  
Structural Abnormalities

SummaryVascular malformations are structural abnormalities, errors of vascular morphogenesis, which can be localized in all parts of the vascular system. All vascular malformations by definition, are present at birth and grow proportionately with the child; their volume can change. In contrast to the haemangiomas, which only proliferate from the endothelial cells the division in stages is of clinical importance. Vascular malformations are divided from the part of vascular system, which is affected.In principle the techniques of laser application in congenital vascular tumours like haemangiomas and in vascular malformations are similar, but the aim is different. In tumours the aim is to induce regression, in vascular malformations the aim is to destroy the pathologic vascular structure because there is no spontaneous regression. This means that the parameters for treatment of vascular malformations must be more aggressive than for vascular tumours.

scholarly journals Blood Flow in Portal Systems with Special Reference to the Rat Pituitary Gland

1992 ◽  
Vol 12 (1) ◽  
pp. 128-138 ◽  
Author(s):  
P. D. Lees ◽  
D. T. Lynch ◽  
H. K. Richards ◽  
A. H. J. Lovick ◽  
S. Perry ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Median Eminence ◽  
Venous Drainage ◽  
Mean Value ◽  
Portal System ◽  
Posterior Pituitary ◽  
Flow Rates ◽  
Fischer 344 ◽  
Rat Pituitary

Regional pituitary blood flow has been studied in adult female Fischer 344 rats by [14C]iodoantipyrine autoradiography. A general mathematical solution has been derived to allow the calculation of blood flow in the second compartment of a portal system and the proportion of blood “shunted” through the first compartment without exposure to tissue uptake from a knowledge of (a) the volume ratios of the two compartments, (b) the tissue tracer uptakes of the two compartments, and (c) the arterial tracer concentration with respect to time of a freely diffusible tracer. Significant diffusion limitation and/or arteriovenous shunting has been demonstrated in the neurohypophysis, suggesting that the majority of incoming blood is “shunted” unchanged to the adenohypophysis. The mean value of the shunt is 89% (range of 84–93%) for the median eminence and lies between 72% (range of 52–82%) and 73% (range of 59–81%) for the posterior pituitary. Neurohypophysial flow rates of 1.20 (range of 0.99–1.55) ml g−1 min−1 for the median eminence and 1.68 (range of 0.83–3.53) ml g−1 min−1 for the posterior pituitary were measured. These values represent “tissue-available” (nonshunted) flow; estimated mean total (shunted plus nonshunted) neurohypophysial flow rates were 11.7 (range of 9.5–17.5) ml g−1 min−1 for the median eminence and 6.1 (range of 3.1–8.9) ml g−1 min−1 (minimum) for the posterior pituitary. Adenohypophysial blood flow is heterogeneous. In the long portal territory, the flow rate was 1.18 (range of 0.95–1.75) ml g−1 min−1 but short portal territory flow calculation is complicated by an unquantifiable nonportal venous drainage; using the natural limits of zero and 100% gives a minimum adenohypophysial flow rate of 1.42 (range of 0.76–2.07) ml g−1 min−1 and a maximum value of 1.97 (range of 1.03–2.82) ml g−1 min−1.

THE VASCULAR STRUCTURE OF THE EXTRAPLACENTAL UTERINE MUCOSA OF THE RABBIT

1950 ◽  
Vol 7 (1) ◽  
pp. 86-99 ◽  
Author(s):  
HELEN J. PARRY
Keyword(s):  
Blood Vessels ◽  
Vascular System ◽  
Maternal Blood ◽  
Uterine Epithelium ◽  
Previous Literature ◽  
Physiological Significance ◽  
Vascular Structure ◽  
Uterine Endometrium ◽  
Early Stages ◽  
Uterine Mucosa

The finer vascular system of the extra-placental uterine mucosa of the rabbit during oestrus and the early stages of pregnancy and pseudopregnancy was studied by means of the benzidine-nitroprusside blood stain and by injection. In the oestrous uterus there is a marked mesometrial hyperaemia which intensifies during the early stages of pregnancy and pseudopregnancy. No spiral arteries nor arterio-venous anastomoses were found in the uterine endometrium. During the early stages of pregnancy, as the uterine mucosa proliferates, there is an intense growth of new blood vessels, accompanied by a corresponding increase in the amount of blood in the vessels. This occurs throughout the uterus at first, but after 8 days post coitum the increase continues around the conceptus but slows down and finally stops between the conceptuses and in the pseudopregnant horn. When the trophoblast of the blastocyst wall fuses with the uterine epithelium the fusion areas become well vascularized. It is suggested that this vascularization is stimulated by the invading trophoblast. The trophoblast actually breaks down the walls of the maternal capillaries and allows the maternal blood to bathe the embryonic syncytium and during the time that this is happening there is a marked leucocytosis around the fusion areas. The results are discussed in relation to the previous literature and to their possible physiological significance.

scholarly journals Phenylmethimazole blocks palmitate-mediated induction of inflammatory cytokine pathways in 3T3L1 adipocytes and RAW 264.7 macrophages

2010 ◽  
Vol 207 (3) ◽  
pp. 343-353 ◽  
Author(s):  
Kelly D McCall ◽  
Dawn Holliday ◽  
Eric Dickerson ◽  
Brian Wallace ◽  
Anthony L Schwartz ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Vascular System ◽  
Biologically Active ◽  
Portal System ◽  
Target Cells ◽  
Raw 264.7 ◽  
Raw 264.7 Macrophages ◽  
Induce Insulin Resistance ◽  
Fat Liver ◽  
First Time

Visceral adipocytes and associated macrophages produce and release excessive amounts of biologically active inflammatory cytokines via the portal and systemic vascular system, which induce insulin resistance in insulin target tissues such as fat, liver, and muscle. Free fatty acids (FFAs) absorbed via the portal system or released from adipocytes also induce insulin resistance. In this report, we show that phenylmethimazole (C10) blocks basal IL6 and leptin production as well as basal Socs-3 expression in fully differentiated 3T3L1 cells (3T3L1 adipocytes) without affecting insulin-stimulated AKT signaling. In addition, C10 inhibits palmitate-induced IL6 and iNos up-regulation in both 3T3L1 adipocytes and RAW 264.7 macrophages, LPS-induced NF-κB and IFN-β activation in 3T3L1 cells, and LPS-induced iNos, Ifn-β, Il1β, Cxcl10, and Il6 expression in RAW 264.7 macrophages. C10 also blocks palmitate-induced Socs-3 up-regulation and insulin receptor substrate-1 (IRS-1) serine 307 phosphorylation in 3T3L1 adipocytes. Additionally, we show for the first time that although palmitate increases IRS-1 serine 307 phosphorylation in 3T3L1 adipocytes, AKT serine 473 phosphorylation is enhanced, not reduced, by palmitate. These results suggest that through inhibition of FFA-mediated signaling in adipocytes and associated macrophages, as well as possibly other insulin target cells/tissues (i.e. non-immune cells), C10 might be efficacious to prevent or reverse cytokine-induced insulin resistance seen in obesity-related insulin resistance and type 2 diabetes mellitus.

scholarly journals Impact of Health Status and Lifestyle Modifications on Vascular Structure and Function in Children and Adolescents

2015 ◽  
Vol 11 (4) ◽  
pp. 330-343
Author(s):  
Donald R. Dengel ◽  
Justin R. Ryder
Keyword(s):  
Cardiovascular Disease ◽  
Children And Adolescents ◽  
Vascular System ◽  
Disease Process ◽  
Structure And Function ◽  
Vascular Structure ◽  
Lifestyle Modifications ◽  
Genetic Abnormalities ◽  
And Function ◽  
Reliable Methods

Until recently cardiovascular disease is often thought of as a disease that manifests itself during middle age. Researchers and clinicians have begun to realize that the initial signs of cardiovascular disease begin early on in childhood with changes present in both vascular structure and function. This increased recognition has resulted in considerable effort to develop accurate and reliable methods to measure as well as track changes in vascular structure and function applicable to study this process in children and adolescents. Certain genetic abnormalities and chronic diseases, which present or emerge in childhood often result in meaningful changes to vascular structure and function, which aid in our understanding of the vascular disease process. In this review, we will discuss different methods of assessing vascular structure and function, the diseases in childhood associated with decrements and maladaptive changes in the vascular system, and whether modification of lifestyle (ie, weight loss, dietary and/or exercise changes) can affect vascular structure and function in children.

Total Anomalous Pulmonary Venous Drainage into the Portal System

Radiology ◽  
1961 ◽  
Vol 76 (6) ◽  
pp. 894-902 ◽  
Author(s):  
Bertram Levin ◽  
Harvey White
Keyword(s):  
Venous Drainage ◽  
Portal System ◽  
Anomalous Pulmonary Venous Drainage

scholarly journals X. The intracranial vascular system of sphenodon

1909 ◽  
Vol 200 (262-273) ◽  
pp. 403-426 ◽  
Keyword(s):  
Blood Vessels ◽  
Vascular System ◽  
Serial Sections ◽  
Cranial Cavity ◽  
The Subject ◽  
Intracranial Arteries ◽  
Arteries And Veins ◽  
The Brain ◽  
Complete Account

In the course of my investigations on the Pineal Apparatus of the Tuatara ( Sphenodon punctas ) I have found it desirable to make as complete a study as possible of the arrangement of the intracranial arteries and veins, of which no description has as yet been published. As any facts relating to the structure of Sphenodon are of more than usual interest, and as I hope to be able to give a more complete account of the subject than has yet been given for any reptile, I have decided to offer my results for publication as a separate memoir, without waiting for the completion of my work on the pineal organs. The blood-vessels have been investigated partly by dissection and partly by means of serial sections, and such completeness of detail as I have been able to attain is very largely due to the adoption of a method of fixing and hardening which I have found to have many advantages both for the study of the vascular system and of the brain itself. By this method the entire contents of the cranial cavity are fixed and hardened in situ , and are then in excellent condition either for dissection or for histological purposes. The application of the method in the case of Sphenodon is greatly facilitated by the fact that the brain does not occupy nearly the whole of the cranial cavity, a large subdural space being left, especially above the brain, across which numerous blood-vessels run, together with delicate strands of connective tissue which connect the dura mater with the pia .

Embryonic and Early Fetal Development of Human Lung Vasculature and Its Functional Implications

2000 ◽  
Vol 3 (5) ◽  
pp. 439-449 ◽  
Author(s):  
Daphne E. deMello ◽  
Lynne M. Reid
Keyword(s):  
Pulmonary Artery ◽  
Human Lung ◽  
Pulmonary Veins ◽  
Pulmonary Vasculature ◽  
Human Embryos ◽  
Vascular Structure ◽  
Serial Sections ◽  
Peripheral Airways ◽  
Functional Implications ◽  
Airway Branching

Recently, we have identified in the mouse three processes involved in the early development of pulmonary vasculature: angiogenesis for branching of central vessels, vasculogenesis (lakes in the mesenchyme) for peripheral vessels, and a lytic process to establish luminal connection between the two. We have established that these three processes also operate in the human by studying serial sections of human embryos and early fetuses. Vascular lakes of hematopoietic cells appear at stage 13, i.e., 4+ weeks gestational age (GA), the first intrapulmonary vascular structure to appear. At stage 20 (50.5 days GA), a venous network with luminal connections to central pulmonary veins (PV) is present. Airways have not yet reached these regions of lung.At its first intrapulmonary appearance, the pulmonary artery (PA) is small and thick walled: it runs with the airway but its branching is slower, so many peripheral airways are not accompanied by a PA branch. By contrast, the PV has a peripheral patent network well before the PA.In the pseudoglandular phase, airway branching continues, and the PA catches up so that small PA branches are found with all airways. Later in this phase small nonmuscular vessels lie in the mesenchyme close to airway epithelium.By the early canalicular phase and the age of viability, continuity between pulmonary artery and the peripheral capillary network must be established. In a 10-week fetus several structures suggesting a breakthrough site were seen. Air-blood barrier structure is first seen at 19 weeks. Thus in the lung, the PA and PV are dissociated in their timing and pattern of branching. Early veins are present diffusely through the mesenchyme and establish central luminal connection to the main pulmonary vein before airway or artery are present at this level.

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