The Distribution of Red Cells in the Spleen

1971 ◽  
Vol 49 (8) ◽  
pp. 734-743 ◽  
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.

Physical Characteristics of Red Cells Collected from the Spleen

1971 ◽  
Vol 49 (12) ◽  
pp. 1092-1099 ◽  
Author(s):  
A. C. Groom ◽  
S. H. Song ◽  
P. Lim ◽  
B. Campling
Keyword(s):  
Bone Marrow ◽  
Specific Gravity ◽  
Ringer Solution ◽  
Red Cells ◽  
Venous Outflow ◽  
Morphological Studies ◽  
Arterial Blood ◽  
Free Cells ◽  
Vascular Channels ◽  
Kinetics Of

Kinetics of cell washout, when isolated cat spleens are perfused with Ringer solution, have shown previously that the red cells stored in the spleen correspond to a system of three compartments (fast, intermediate, and slow); morphological studies, at different stages of the washout, have already identified these compartments as free cells in vascular channels, free cells within sinuses, and cells adhering to sinus walls, respectively. By collecting the venous outflow at three particular stages of the washout fairly pure samples (>85%) of the cells from each compartment have now been obtained. We have measured the density (phthalate method), volume, and osmotic changes (Celloscope) of these cells. Cells from the fast and intermediate compartments were not significantly different from those of arterial blood, but cells from the slow compartment were lighter (specific gravity difference was 0.0064; p < 0.01), larger in volume (5.0%; p < 0.01), and swelled 14% less in 200 mOsmol/l (p < 0.01). These differences indicated that cells from the slow compartment might be predominantly younger cells and this has been confirmed by finding reticulocyte counts of 58.0 ± 3.8 (S.E.) %. It is suggested that immature red cells, released from the bone marrow, may be sequestered in the spleen and matured.

Release of red cells from the slowly-exchanging splenic pool after noradrenaline administration

1976 ◽  
Vol 54 (4) ◽  
pp. 477-484 ◽  
Author(s):  
H. B. Geiger ◽  
S. H. Song ◽  
A. C. Groom
Keyword(s):  
Time Course ◽  
Cell Concentration ◽  
Splenic Vein ◽  
Ringer Solution ◽  
Red Cells ◽  
Red Cell ◽  
Outflow Rate ◽  
Abnormal Cells ◽  
Noradrenaline Administration ◽  
Red Pulp

Isolated, denervated, cat spleens were perfused at constant flow with modified Ringer solution. Perfusion pressure, outflow rate, and outflow red cell concentration were measured against time. After splenic perfusion by 500 ml solution the cell washout curve became a single exponential function, indicating that only cells from the most slowly exchanging red cell compartment remained (these are immature and abnormal cells which adhere to the fine structures of the red pulp). Splenic contraction was induced by injection of 5 μg noradrenaline into the inflow after perfusion by 600 and 1000 ml of fluid, respectively; outflow cell concentration rose 17-fold before returning to baseline value and 32% of red cells in the spleen were expelled. The time course of changes in cell concentration was similar in shape but delayed with respect to that of outflow rate. The transit time of the cells from the site of release to the splenic vein must have exceeded 40 s, which is consistent only with release from the red pulp. Furthermore, at the peak of the cell concentration curve the mean reticulocyte count was 37.8%. Thus immature and abnormal red cells, which comprise the slowly-exchanging compartment, are indeed released from the spleen during contraction.

Scanning Electron Microscopy of the Red Pulp of the Spleen

1971 ◽  
Vol 29 ◽  
pp. 496-497
Author(s):  
Masayuki Miyoshi
Keyword(s):  
Electron Microscope ◽  
Ringer Solution ◽  
Conclusive Evidence ◽  
Sinus Wall ◽  
Transmission Electron ◽  
Type 3 ◽  
Cytoplasmic Processes ◽  
Splenic Red Pulp ◽  
Scanning Electron ◽  
Red Pulp

In spite of various attempts, conclusive evidence to explain blood passage in the splenic red pulp does not seem to have been presented. Scanning electron microscope (SEM) observations on the rabbit spleen, originally performed by us, revealed that the sinus was lined by a perforated lattice composed of longitudinally extended rod cells and transverse cytoplasmic processes, and that perforations in the lattice were continuous to the spaces among the stellate reticulum cells of the cord. In the present study the observation was extended to the dog and rat spleens, in which the cord is more developed than in the rabbit in order to clarify the possible differences in the fine structure of the sinus wall. An attempt was also made to examine the development and distribution of macrophage in the blood passage of the red pulp.Spleens were washed and fixed by perfusion with Ringer solution and then with buffered glutaraldehyde. Small tissue cubes were dehydrated with acetone, dried in air and heated with gold. Observations were made by a JEOL SEM Type-3. One air dried tissue cube was cut into small pieces and post fixed with buffered OsO4 for examination under the transmission electron microscope (TEM).

Description of a Simple Model for the Study of Bone Calcium Metabolism

1980 ◽  
Vol 19 (01) ◽  
pp. 11-15
Author(s):  
G. Roncari ◽  
L. Rapisardi ◽  
L. Conte ◽  
G. Pedroli
Keyword(s):  
Simple Model ◽  
Calcium Metabolism ◽  
Good Description ◽  
Radioactive Tracer ◽  
Normal Subjects ◽  
Bone Diseases ◽  
Compartment System ◽  
Bone Calcium ◽  
Finite Period ◽  
Kinetics Of

A simple model for the study of bone calcium metabolism is proposed. It describes the kinetics of a radioactive tracer in terms of an open single compartment system with an expanding volume for a finite period of time. In addition to the simplicity of the hypotheses introduced, the model is able to give a good description of the biological processes which regulate calcium kinetics. Moreover the functional parameters can be easily calculated, even just graphically. 15 normal subjects and 22 patients affected by various bone diseases were studied. The results were compared with those obtained by using the model proposed by Burkinshaw et al. and the method described by Reeve et al.

scholarly journals CD19 Cell Count at Baseline Predicts B Cell Repopulation at 6 and 12 Months in Multiple Sclerosis Patients Treated with Ocrelizumab

2021 ◽  
Vol 18 (15) ◽  
pp. 8163
Author(s):  
Gianmarco Abbadessa ◽  
Giuseppina Miele ◽  
Paola Cavalla ◽  
Paola Valentino ◽  
Girolama Alessandra Marfia ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Count ◽  
Considerable Proportion ◽  
Cell Counts ◽  
Time Scheduling ◽  
Magnetic Resonance Imaging Mri ◽  
Multiple Sclerosis Patients ◽  
Kinetics Of ◽  
Cell Repopulation

Background: The kinetics of B cell repopulation in MS patients treated with Ocrelizumab is highly variable, suggesting that a fixed dosage and time scheduling might be not optimal. We aimed to investigate whether B cell repopulation kinetics influences clinical and radiological outcomes and whether circulating immune asset at baseline affects B cell repopulation kinetics. Methods: 218 MS patients treated with Ocrelizumab were included. Every six months we collected data on clinical and magnetic resonance imaging (MRI) activity and lymphocyte subsets at baseline. According to B cell counts at six and twelve months, we identified two groups of patients, those with fast repopulation rate (FR) and those with slow repopulation rate (SR). Results: A significant reduction in clinical and radiological activity was found. One hundred fifty-five patients had complete data and received at least three treatment cycles (twelve-month follow-up). After six months, the FR patients were 41/155 (26.45%) and 10/41 (29.27%) remained non-depleted after twelve months. FR patients showed a significantly higher percentage of active MRI scan at twelve months (17.39% vs. 2.53%; p = 0,008). Furthermore, FR patients had a higher baseline B cell count compared to patients with an SR (p = 0.02 and p = 0.002, at the six- and twelve-month follow-ups, respectively). Conclusion: A considerable proportion of MS patients did not achieve a complete CD19 cell depletion and these patients had a higher baseline CD19 cell count. These findings, together with the higher MRI activity found in FR patients, suggest that the Ocrelizumab dosage could be tailored depending on CD19 cell counts at baseline in order to achieve complete disease control in all patients.

Myocardial CO2 buffering: role of transmembrane transport of H+ or HCO3-ions

1976 ◽  
Vol 230 (4) ◽  
pp. 1037-1041 ◽  
Author(s):  
DR Strome ◽  
RL Clancy ◽  
NC Gonzalez
Keyword(s):  
Small Volume ◽  
Coronary Circulation ◽  
Myocardial Cell ◽  
Ringer Solution ◽  
Red Cells ◽  
Transmembrane Transport ◽  
High Degree

Isolated rabbit hearts were perfused with rabbit red cells suspended in Ringer solution. A small volume of perfusate was recirculated for 10 min at Pco2 of 33.4 +/- 0.9 or 150.8 +/- 7.5 mmHg. Hypercapnia resulted in an increase in perfusate HCO3- concentration that was smaller than that observed when isolated perfusate was equilibrated in vitro with the same CO2 tensions (delta HCO-3e = 1.6 mM, P less than 0.01). This difference is consistent with a net movement of HCO3- into or H+ out of the mycardial cell, and cannot be accounted for by dilution of HCO3- in the myocardial interstitium. Recirculation of perfusate through the coronary circulation at normal Pco2 for two consecutive 10-min periods was not followed by changes in perfusate HCO3- concentration. A high degree of correlation (r = 0.81) was observed between intracellular HCO-3e concentration and the corresponding delta HCO-3e in individual experiments. The results suggest that transmembrane exchange of H+ or HCO3- is a buffer mechanism for CO2 in the myocardial cell.

scholarly journals A comparison of the short-term kinetics of zinc metabolism in women during fasting and following a breakfast meal

1998 ◽  
Vol 80 (4) ◽  
pp. 363-370 ◽  
Author(s):  
Nicola M. Lowe ◽  
Leslie R. Woodhouse ◽  
Janet C. King
Keyword(s):  
Energy Content ◽  
Compartment Model ◽  
Zinc Metabolism ◽  
Short Term ◽  
Compartment System ◽  
Breakfast Meal ◽  
Physiological Importance ◽  
Two Compartment Model ◽  
Zn Concentration ◽  
Kinetics Of

The physiological importance and mechanism of the postprandial fall in plasma Zn concentration is not well understood. In order to gain further information on this apparent redistribution of plasma Zn, a stable isotope, 70Zn, was used to study the effect of a breakfast meal on plasma Zn kinetics. Nine women participated in two trials, a fasting trial and a breakfast-meal trial; five of the women participated in a third trial in which the energy content of the breakfast meal was doubled. At each trial, 0.1mg of 70Zn was infused intravenously, and the plasma disappearance of the isotope was analysed using a two-compartment model of Zn kinetics. Plasma Zn concentration fell significantly following the two trials in which the subjects were given meals, reaching low points that were 13 and 19 %, respectively, below concentrations at comparable times during the fasting trial. Kinetic analysis revealed that after the doubled breakfast meal there was a significant fall (P < 0.007) in the size of the most rapidly turning over Zn pool (pool (a)) from 2.90 (se 0.13)mg in the fasting state to 2.47 (se 0.14) mg postprandially. The fractional turnover rate of pool (a) to other extravascular Zn pools, i.e. outside the two-compartment system, was also significantly elevated after the doubled breakfast meal (P < 0.05). These results suggest that the decline in plasma Zn concentration following a meal is due to a redistribution of Zn from the plasma to other more slowly turning over extravascular pools that may be involved in the assimilation and metabolism of fuels following food intake.

Comparative Clearance Kinetics of Beat Damaged (Hdrc) and Antibody Coated Red Cells (Igrc)

1982 ◽  
Vol 62 (2) ◽  
pp. 7P-7P ◽  
Author(s):  
A.M. Peters ◽  
M. J. Walport ◽  
K. B. Elkon ◽  
P. P. Ferjencik ◽  
G. R. V. Hughes ◽  
...  
Keyword(s):  
Red Cells ◽  
Clearance Kinetics ◽  
Kinetics Of

The Leeuwenhoek Lecture, 1978 Bacteria as proper subjects for cancer research

1980 ◽  
Vol 208 (1171) ◽  
pp. 121-133 ◽  
Keyword(s):  
Gene Expression ◽  
Stem Cells ◽  
Cancer Research ◽  
Mammalian Cells ◽  
Cell Renewal ◽  
Epigenetic Alterations ◽  
Cell Lineages ◽  
Abnormal Cells ◽  
Kinetics Of

Cancers are clones of abnormal cells, arising presumably as the result of mutational or epigenetic alterations of gene expression. The kinetics of appearance of spontaneous cancers in populations of multiplying cells (i. e. the relation between age and cancer incidence) will therefore depend, among other things, on how these populations are organized and, in general, on the kinetics of the response of cells to prolonged mutagenesis. The organization of cell renewal in epithelia (i. e. the arrangement of cell lineages) is still rather obscure; in particular, it is not known to what extent the properties and organization of the stem cells tend to protect them from accumulating mutations. We have tried to mimic the arrangement of epithelia by attaching multiplying bacteria to filters. Study of mutagenesis in long-term cultures of such anchored bacteria has led to the discovery of some additional pathways for DNA repair which also appear to operate in mammalian cells.

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