High capillary diameter in psoriatic plaques of the lower legs

2020 ◽  
Vol 182 (4) ◽  
pp. 1064-1065
Author(s):  
F. Lacarrubba ◽  
A.E. Verzì ◽  
M.L. Musumeci ◽  
G. Micali
Keyword(s):  
Capillary Diameter

In vivo microvascular structural and functional consequences of muscle length changes

1997 ◽  
Vol 272 (5) ◽  
pp. H2107-H2114 ◽  
Author(s):  
D. C. Poole ◽  
T. I. Musch ◽  
C. A. Kindig
Keyword(s):  
Blood Flow ◽  
Blood Cell ◽  
Red Blood Cell ◽  
Oxygen Delivery ◽  
Sarcomere Length ◽  
Flow Dynamics ◽  
Capillary Diameter ◽  
Luminal Diameter ◽  
Length Changes

As muscles are stretched, blood flow and oxygen delivery are compromised, and consequently muscle function is impaired. We tested the hypothesis that the structural microvascular sequellae associated with muscle extension in vivo would impair capillary red blood cell hemodynamics. We developed an intravital spinotrapezius preparation that facilitated direct on-line measurement and alteration of sarcomere length simultaneously with determination of capillary geometry and red blood cell flow dynamics. The range of spinotrapezius sarcomere lengths achievable in vivo was 2.17 +/- 0.05 to 3.13 +/- 0.11 microns. Capillary tortuosity decreased systematically with increases of sarcomere length up to 2.6 microns, at which point most capillaries appeared to be highly oriented along the fiber longitudinal axis. Further increases in sarcomere length above this value reduced mean capillary diameter from 5.61 +/- 0.03 microns at 2.4-2.6 microns sarcomere length to 4.12 +/- 0.05 microns at 3.2-3.4 microns sarcomere length. Over the range of physiological sarcomere lengths, bulk blood flow (radioactive microspheres) decreased approximately 40% from 24.3 +/- 7.5 to 14.5 +/- 4.6 ml.100 g-1.min-1. The proportion of continuously perfused capillaries, i.e., those with continuous flow throughout the 60-s observation period, decreased from 95.9 +/- 0.6% at the shortest sarcomere lengths to 56.5 +/- 0.7% at the longest sarcomere lengths and was correlated significantly with the reduced capillary diameter (r = 0.711, P < 0.01; n = 18). We conclude that alterations in capillary geometry and luminal diameter consequent to increased muscle sarcomere length are associated with a reduction in mean capillary red blood cell velocity and a greater proportion of capillaries in which red blood cell flow is stopped or intermittent. Thus not only does muscle stretching reduce bulk blood (and oxygen) delivery, it also alters capillary red blood cell flow dynamics, which may further impair blood-tissue oxygen exchange.

Capillary diameter and geometry in cardiac and skeletal muscle studied by means of corrosion casts

1983 ◽  
Vol 25 (1) ◽  
pp. 68-84 ◽  
Author(s):  
R.F. Potter ◽  
A.C. Groom
Keyword(s):  
Skeletal Muscle ◽  
Corrosion Casts ◽  
Capillary Diameter

Influence of intratubular pressure on proximal tubular compliance and capillary diameter in the rat kidney

1979 ◽  
Vol 382 (2) ◽  
pp. 179-187 ◽  
Author(s):  
Peter Koch Jensen ◽  
Kenneth Steven
Keyword(s):  
Rat Kidney ◽  
Capillary Diameter ◽  
Intratubular Pressure ◽  
Proximal Tubular

Capillary diameter in rat heart in situ: Relation to erythrocyte deformability, O2 transport, and transmural O2 gradients

1976 ◽  
Vol 12 (3) ◽  
pp. 259-274 ◽  
Author(s):  
Louis Henquell ◽  
Paul L. LaCelle ◽  
Carl R. Honig
Keyword(s):  
Rat Heart ◽  
Erythrocyte Deformability ◽  
Capillary Diameter ◽  
O2 Transport

Regression method in capillary diameter measurement

1990 ◽  
Vol 33 (8) ◽  
pp. 768-771
Author(s):  
A. B. Androsik ◽  
S. D. Mirovitskaya ◽  
Sh. I. Pantskhava ◽  
G. V. Fateeva
Keyword(s):  
Regression Method ◽  
Capillary Diameter ◽  
Diameter Measurement

Increasing capillary diameter and the incorporation of gelatin enhance axon outgrowth in alginate-based anisotropic hydrogels

2011 ◽  
Vol 7 (7) ◽  
pp. 2826-2834 ◽  
Author(s):  
Kiran Pawar ◽  
Rainer Mueller ◽  
Massimiliano Caioni ◽  
Peter Prang ◽  
Ulrich Bogdahn ◽  
...  
Keyword(s):  
Axon Outgrowth ◽  
Capillary Diameter

scholarly journals Inner capillary diameter of hypothalamic paraventricular nucleus of female rat increases during lactation

2013 ◽  
Vol 14 (1) ◽  
Author(s):  
Albertina Cortés-Sol ◽  
Miguel Lara-Garcia ◽  
Mayvi Alvarado ◽  
Robyn Hudson ◽  
Pere Berbel ◽  
...  
Keyword(s):  
Paraventricular Nucleus ◽  
Hypothalamic Paraventricular Nucleus ◽  
Female Rat ◽  
Capillary Diameter

Guided transmission of 3-keV Ne7+ions through nanocapillaries in insulating polymers: Dependence on the capillary diameter

2010 ◽  
Vol 82 (5) ◽  
Author(s):  
N. Stolterfoht ◽  
R. Hellhammer ◽  
Z. Juhász ◽  
B. Sulik ◽  
E. Bodewits ◽  
...  
Keyword(s):  
Capillary Diameter ◽  
Insulating Polymers

scholarly journals Experimental evaluation of the mechanical degradation of HPAM polymeric solutions used in Enhanced Oil Recovery

2020 ◽  
Vol 10 (2) ◽  
pp. 131-141
Author(s):  
Gustavo Maya Toro ◽  
Julia Jineth Herrera Quintero ◽  
Ruben Hernan Castro Garcia ◽  
Henderson Ivan Quintero Pérez ◽  
Dalje Sunith Barbosa Trillos ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Polymer Solutions ◽  
Fractional Factorial ◽  
Pressure Differential ◽  
Influential Factor ◽  
Mechanical Degradation ◽  
Capillary Diameter ◽  
Degradation Rates

With the design of experiments (DoE), this study analyses the influence of physical (capillary diameter and pressure drop) and chemical variables (salinity, polymer concentration, and molecular weight) on the mechanical degradation of partially hydrolyzed polyacrylamide-type polymer solutions (HPAM) used in enhanced oil recovery processes. Initially, with the help of a fractional factorial design (2k-p), the variables with the most significant influence on the polymer's mechanical degradation were found. The experimental results of the screening demonstrate that the factors that statistically influence the mechanical degradation are the molecular weight, the diameter of the capillary, and the pressure differential. Subsequently, a regression model was developed to estimate the degradation percentages of HPAM polymer solutions as a function of the significant factors influencing the mechanical degradation of polymer solutions. This model had a 97.85% fit for the predicted values under the experimental conditions. Likewise, through the optimization developed by the Box Behnken response surface methodology, it was determined that the pressure differential was the most influential factor. This variable was followed by the capillary diameter, where less than 50% degradation rates are obtained with low polymer molecular weight (6.5 MDa), pressure differentials less than 500 psi, and diameters of the capillary greater than 0.125 inches.

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