A mathematical representation for vessel network III.

I I Chen

doi:10.1016/s0022-5193(84)80199-x

Home/Archive/PubMed

PubMed · 6513563

A mathematical representation for vessel network III.

I I Chen

View original source ↗Export metadata ↓

Abstract

The loop vascular network is found frequently within biological tissue, but a schematic characterization of the loop vascular network is at present difficult to describe. The reason is that the topographical feature of vessel loop can change during maturation. In this article, we treat the mathematical representation of the loop vessel network, and discuss the application of this to the increased vascular resistance in hypertensive animals resulting from microvascular rarefaction. On the other hand, the number of regions into which the tissue plane is divided by n bifurcational tree branches is derived from recurrence relation.

Explore related subjects

Arterioles Blood Vessels Capillaries Humans Mathematics Microcirculation Models, Cardiovascular Vascular Resistance Venules Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

I I Chen. 1984-11-07. A mathematical representation for vessel network III.. https://doi.org/10.1016/s0022-5193(84)80199-x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Endothelial nitric oxide synthase in human intestine resected for necrotizing enterocolitis.

OBJECTIVE: To determine the expression and function of endothelial nitric oxide synthase (eNOS) in submucosal arterioles harvested from human intestine resected for necrotizing enterocolitis (NEC) or congenital bowel disease. STUDY DESIGN: eNOS expression was determined by using immunohistochemistry. The arteriolar diameter was measured in vitro at pressures of 10 to 40 mm Hg and also in response to the eNOS agonist acetylcholine (ACh), the exogenous nitric oxide (NO) donor S-nitroso-N-acetylpenicillamine, and the smooth muscle relaxant papaverine. Arteriolar release of NO in response to ACh was determined with a Sievers NOAnalyzer. Hemodynamics were also determined at flow rates of 50 and 100 microL/min. RESULTS: eNOS was present in microvessels from both groups, but NEC arterioles failed to demonstrate physiological evidence of eNOS function: they constricted in response to pressure, failed to dilate or generate NO in response to ACh, and failed to dilate in response to flow. However, they dilated in response to exogenous NO and papaverine, indicating functional vascular smooth muscle and vasodilator reserve. CONCLUSION: eNOS-derived NO, a vasodilator in the newborn intestine, did not contribute to vasoregulation in arterioles harvested from intestine resected for NEC. These vessels were constricted; lack of eNOS-derived NO may contribute to this vasoconstriction.

Arterioles↗

PubMed2007

BMI and retinal vascular caliber in children.

OBJECTIVE: In adult populations, changes in retinal vascular caliber have been linked with obesity and metabolic syndrome. We examined the association of BMI and weight with retinal vascular caliber in children. RESEARCH METHODS AND PROCEDURES: This was a school-based, cross-sectional study of 768 children, 7 to 9 years old, randomly sampled from the Singapore Cohort Study of the Risk Factors for Myopia. Participants had digital retinal photographs. Retinal vascular caliber was measured using a computer-based program and combined to provide average calibers of arterioles and venules in that eye. Weight and height were measured using standardized protocol. These data were used to calculate BMI. RESULTS: In this population, the mean retinal arteriolar and venular calibers were 156.40 microm [95% confidence interval (CI), 155.44 to 157.36] and 225.43 microm (95% CI, 224.10 to 226.74) respectively. After controlling for age, gender, race, parental monthly income, axial length, birth weight, and birth length, each 3.1 kg/m2 (standard deviation) increase in BMI was associated with a 2.55-microm (95% CI, 1.21 to 3.89; p < 0.001) larger retinal venular caliber. In multivariable analysis, greater weight was also significantly associated with larger retinal venular caliber. BMI and weight were not associated with retinal arteriolar caliber. Height was not significantly associated with retinal arteriolar or venular caliber. DISCUSSION: Greater BMI and weight are associated with larger retinal venular caliber in healthy children.

Arterioles↗

PubMed2006

Anatomic bases of vascularized elbow joint harvesting to achieve vascularized allograft.

In order to later make precise the operative technique of free vascularized elbow allograft transfer, the anatomic conditions necessary for the success of such an operation are reviewed. The exact topography of the nutrient foramina of the humerus, radius, and ulna has been specified on 102 dry bones. The osseous resection at the recipient will have to be carried out on these aspects: nutrient foramina of the three bones of the elbow (at 9 cm from medial epicondyle for the humerus; at 8 cm for the two bones of forearm) in order to preserve diaphysary vascularization of the recipient. A study of arterial and venous vascularization carried out on 18 anatomic specimens showed that the osseous ends were irrigated by a periosteal arterial network and were drained in the centromedullary cavities. Systematization of the arteriovenous blood supply of the distal end of the humerus and proximal ends of the two forearm bones is proposed after dissection of 18 anatomic specimens. Arterial periosteal territories are defined. The importance of each peri articular arteriole is estimated according to the surface of its respective section. A radial, constant, and musculoperiosteal collateral artery from the brachial artery is described. It accounts for 12% (+/- 3%) of the total contribution. The recurrent radial artery is the most significant: 31% (+/- 9%) of the total contribution. The profunda brachii artery is negligible: 4% (+/- 2%) of the total contribution. As well for vascular as mechanical reasons, osteosynthesis will have to be carried out using screwed plates, the optimal location of which is specified according to the arterial periosteal cartography. Ulnar and radial nerves and, to a lesser extent, the median nerve can be harvested "en bloc" preserving their vascular supply in order to make vascularized grafts of them. Free vascularized elbow allograft transfer is technically possible, if one respects these anatomic bases.

Arterioles↗