Volume kinetics of Ringer solution after surgery for hip fracture

It remains uncertain whether the delayed onset of mitochondrial respiration on initiation of muscle contractions is related to O2 availability. The purpose of this research was to measure the kinetics of the fall in intracellular Po 2 at the onset of a contractile work period in rested and previously worked single skeletal muscle fibers. Intact single skeletal muscle fibers ( n = 11) from Xenopus laevis were dissected from the lumbrical muscle, injected with an O2-sensitive probe, mounted in a glass chamber, and perfused with Ringer solution (Po 2 = 32 ± 4 Torr and pH = 7.0) at 20°C. Intracellular Po 2 was measured in each fiber during a protocol consisting sequentially of 1-min rest; 3 min of tetanic contractions (1 contraction/2 s); 5-min rest; and, finally, a second 3-min contractile period identical to the first. Maximal force development and the fall in force (to 83 ± 2 vs. 86 ± 3% of maximal force development) in contractile periods 1 and 2, respectively, were not significantly different. The time delay (time before intracellular Po 2 began to decrease after the onset of contractions) was significantly greater ( P < 0.01) in the first contractile period (13 ± 3 s) compared with the second (5 ± 2 s), as was the time to reach 50% of the contractile steady-state intracellular Po 2(28 ± 5 vs. 18 ± 4 s, respectively). In Xenopus single skeletal muscle fibers, 1) the lengthy response time for the fall in intracellular Po 2 at the onset of contractions suggests that intracellular factors other than O2 availability determine the on-kinetics of oxidative phosphorylation and 2) a prior contractile period results in more rapid on-kinetics.

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Washout kinetics of red cells and plasma from the spleen

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.231.6.1665 ◽

1976 ◽

Vol 231 (6) ◽

pp. 1665-1671 ◽

Cited By ~ 19

Author(s):

MJ Levesque ◽

AC Groom

Keyword(s):

Ringer Solution ◽

Red Cell ◽

Compartment Analysis ◽

Vascular Space ◽

Cell Components ◽

Arterial Inflow ◽

Fine Structures ◽

Immature Cells ◽

Kinetics Of ◽

Red Pulp

Radioiodinated (125I) serum albumin was injected inttravenously in cats and allowed to equilibrate in the circulation. Red cell and plasma washout from the isolated spleens were enrom the isolated spleens were then compared during perfusion with oxygenated Ringer solution, the respective concentrations in the outflow being measured by celloscope and scintillation counters. Washout kinetics yielded three exponential components for cells (perfusate volumes for 50% washout (V1/2) being 0.067, 4.70, and 97 ml/g spleen) but only two for plasm (V1/2, 0.14 and 2.40 ml/g). There is no plasma counterpart to the slowly released cells, i.e., they do not represent a separate vascular space. This is an accord with a previous view that these are immature cells, delayed through adherence to fine structures of the red pulp. Compartment analysis indicates that the plasma and two remaining cell components represent washout from two separate vascular spaces, containing 0.09 ml/g blood at arterial hematocrit 37% and 0.42 ml/g blood at hematocrit 75%, perfused by 0.9 and 0.1 of the arterial inflow respectively. Evidence suggests these spaces are i) blood vessels, and ii) red pulp.

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Faculty Opinions recommendation of Natural history and tumor volume kinetics of papillary thyroid cancers during active surveillance.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.730364261.793541185 ◽

2018 ◽

Author(s):

Sebastiano Filetti

Keyword(s):

Natural History ◽

Active Surveillance ◽

Tumor Volume ◽

Papillary Thyroid ◽

Thyroid Cancers ◽

Volume Kinetics ◽

Kinetics Of

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The Distribution of Red Cells in the Spleen

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y71-100 ◽

1971 ◽

Vol 49 (8) ◽

pp. 734-743 ◽

Cited By ~ 14

Author(s):

S. H. Song ◽

A. C. Groom

Keyword(s):

Inclusion Bodies ◽

Ringer Solution ◽

Red Cells ◽

Compartment System ◽

Cell Counts ◽

Sinus Wall ◽

Free Cells ◽

Abnormal Cells ◽

Vascular Channels ◽

Kinetics Of

Kinetics of red cell washout, when isolated cat spleens are perfused with Ringer solution, show that the spleen corresponds to a three-compartment system. To determine whether or not there exist morphological counterparts to these compartments we examined microscopic sections from 16 spleens perfused by different volumes of Ringer solution. Red cells could be divided into three groups: (1) free cells in vascular channels and sinuses, (2) cells adhering to reticulum cells or sinus endothelium, and (3) cells in the cytoplasm of macrophages. When 50 ml were perfused no free cells were seen in vascular channels. After 600 ml few free cells remained in the sinuses. Thereafter the number of cells adhering to the sinus wall decreased gradually and cell counts agreed with predictions from the washout curve. We conclude that the compartments of our model (fast, intermediate, and slow) represent, respectively, free cells in vascular channels, free cells within sinuses, and cells adhering to sinus walls. The only cells trapped irreversibly are the very few found in the cytoplasm of macrophages. It is suggested that the slow compartment represents red cells in a pre-phagocytosed stage, e.g. aged cells, abnormal cells containing inclusion bodies, and possibly, reticulocytes in the process of maturation.

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