Physiological studies on trematodes: the osmotic activity of Gastrothylax crumenifer

Parasitology ◽  
1966 ◽  
Vol 56 (1) ◽  
pp. 101-104 ◽  
Author(s):  
Madan M. Goil
Keyword(s):  
Sodium Chloride ◽  
Osmotic Pressure ◽  
Freezing Point ◽  
Percentage Change ◽  
Freezing Point Depression ◽  
Gastrothylax Crumenifer ◽  
Physiological Studies ◽  
Osmotic Activity

The percentage change in weight, at 38·2 °C, in different concentrations of sodium chloride at different intervals, of a trematode, Gastrothylax crumenifer, from the reticulum of buffaloes has been recorded.A state of approximate isotonicity is reached between 0·4 and 0·5% sodium chloride.The osmotic pressure has also been expressed in terms of freezing-point depression.

Colloid osmotic pressure changes of dog's blood exposed to different mixtures of CO2 and air

1978 ◽  
Vol 44 (2) ◽  
pp. 254-257 ◽  
Author(s):  
Y. Kakiuchi ◽  
A. B. DuBois ◽  
D. Gorenberg
Keyword(s):  
Red Blood Cells ◽  
Osmotic Pressure ◽  
Cell Volume ◽  
Blood Cells ◽  
Freezing Point ◽  
Colloid Osmotic Pressure ◽  
Red Cell ◽  
Freezing Point Depression ◽  
Pressure Changes ◽  
Different Levels

Hansen's membrane manometer method for measuring plasma colloid osmotic pressure was used to obtain the osmolality changes of dogs breathing different levels of CO2. Osmotic pressure was converted to osmolality by calibration of the manometer with saline and plasma, using freezing point depression osmometry. The addition of 10 vol% of CO2 to tonometered blood caused about a 2.0 mosmol/kg H2O increase of osmolality, or 1.2% increase of red blood cell volume. The swelling of the red blood cells was probably due to osmosis caused by Cl- exchanged for the HCO3- which was produced rapidly by carbonic anhydrase present in the red blood cells. The change in colloid osmotic pressure accompanying a change in co2 tension was measured on blood obtained from dogs breathing different CO2 mixtures. It was approximately 0.14 mosmol/kg H2O per Torr Pco2. The corresponding change in red cell volume could not be calculated from this because water can exchange between the plasma and tissues.

Freezing point depression of rat kidney slices during water diuresis and antidiuresis

1960 ◽  
Vol 199 (5) ◽  
pp. 915-918 ◽  
Author(s):  
George A. Bray
Keyword(s):  
Pressure Gradient ◽  
Osmotic Pressure ◽  
Freezing Point ◽  
Rat Kidney ◽  
Freezing Point Depression ◽  
Water Diuresis ◽  
Outer Medulla ◽  
Kidney Slices ◽  
Outer Stripe ◽  
Osmotic Pressure Gradient

The freezing point depression of slices of rat kidney removed during water diuresis or antidiuresis has been investigated with a microcryoscopic method. The osmotic pressure gradient in the inner medulla first demonstrated by Wirz has been confirmed. The inner medulla was found to be hypertonic to plasma during water diuresis. Hypotonic tubules were present throughout the cortex and outer stripe of the outer medulla.

Correction for loss of CO2 from blood during measurement of osmotic pressure

1978 ◽  
Vol 44 (3) ◽  
pp. 474-478 ◽  
Author(s):  
S. S. Khosla ◽  
A. B. DuBois
Keyword(s):  
Vapor Pressure ◽  
Blood Sample ◽  
Osmotic Pressure ◽  
Freezing Point ◽  
Gas Mixture ◽  
Sample Holder ◽  
Freezing Point Depression ◽  
Pressure Method ◽  
Sample Chamber

During osmolality measurement by the vapor pressure method, exposure of the blood sample to air lowers the blood CO2 content and hence osmolality. A modification of the sample holder of a vapor pressure osmometer is described allowing exposure of the blood sample to a gas mixture with known concentration of CO2 and O2 while inside the closed sample chamber. This restores its CO2 content and hence osmolality. Data are presented comparing the unmodified and modified vapor pressure method with the freezing point depression method. A table was prepared for further correction of osmolality in case the blood's PCO2 differs from that of the gas mixture.

scholarly journals FREEZING POINTS OF ANTI-COAGULANT SALT SOLUTIONS

1935 ◽  
Vol 18 (4) ◽  
pp. 485-490 ◽  
Author(s):  
David I. Hitchcock ◽  
Ruth B. Dougan
Keyword(s):  
Sodium Chloride ◽  
Linear Function ◽  
Sodium Citrate ◽  
Freezing Point ◽  
Biological Fluid ◽  
Linear Equations ◽  
Freezing Point Depression ◽  
Salt Solutions ◽  
Freezing Points ◽  
Sodium Chloride Solutions

By a method involving equilibration of ice and solution, and analysis of the solution, freezing point depressions of solutions of sodium citrate, oxalate, and fluoride have been determined over the range Δ = 0.45 to 0.65°C. Determinations with sodium chloride solutions have confirmed the accuracy of the method. In each case the freezing point depression is given, within 0.002°C., as a linear function of the concentration. By the use of these linear equations it is possible to prepare a solution of any of these four salts isotonic with a given biological fluid of known freezing point, provided the latter falls within the range studied.

The Site of Formation of Hypotonic Urine in the Nephridium of Lumbricus

1949 ◽  
Vol 26 (1) ◽  
pp. 65-75 ◽  
Author(s):  
J. A. RAMSAY
Keyword(s):  
Osmotic Pressure ◽  
Freezing Point ◽  
Freezing Point Depression ◽  
Narrow Tube ◽  
Wide Tube ◽  
Different Parts

1. Methods for the collection of samples of urine from different parts of the nephridium of Lumbricus are described. 2. The osmotic pressures of these samples have been measured by determination of freezing-point depression and have been compared with the osmotic pressure of the medium surrounding the nephridium. 3. The results of this comparison indicate that the ability to form hypotonic urine is certainly present in the wide tube, is possibly present in the middle tube and is probably not present in the narrow tube. 4. The analogy between the nephridium and the vertebrate nephron is discussed.

Concentration Guidelines for Parenteral Antibiotics in Fluid-Restricted Patients

1987 ◽  
Vol 21 (12) ◽  
pp. 985-989 ◽  
Author(s):  
Daniel C. Robinson ◽  
Thomas L. Cookson ◽  
Joseph A. Grisafe
Keyword(s):  
Sodium Chloride ◽  
Freezing Point ◽  
Sterile Water ◽  
Freezing Point Depression ◽  
Three Solutions ◽  
Significant Incidence ◽  
Intravenous Antibiotics

A guideline for the preparation of peripherally administered antibiotics in fluid-restricted patients was developed. A maximum osmolality of 560 mOsmol/kg was selected since this corresponds to the theoretical osmolality of dextrose 5% in NaCl 0.9%, a solution commonly administered peripherally without significant incidence of phlebitis. Percentage concentrations corresponding to 560 mOsmol/kg of 26 intravenous antibiotics were calculated using sodium chloride equivalents. The antibiotics were reconstituted using sterile water, dextrose 5%, and NaCl 0.9% to provide an osmolality of 560 mOsmol/kg. The resulting solutions were measured for osmolality using a freezing-point depression osmometer. A total of 78 solutions were prepared and measured in triplicate. Of the 78 measured osmolalities, 67 (86 percent) were within 20 percent of the desired 560 mOsmol/kg. Only two osmolalities were more than 10 percent above the projected value. The percentage concentrations of 26 antibiotics in three solutions corresponding to 560 mOsmol/kg are presented. A method is also provided for tailoring concentrations to achieve desired osmolalities other than 560 mOsmol/kg.

Micropuncture Studies Of Chloride Concentration and Osmotic Pressure in the Crayfish Antennal Gland

1963 ◽  
Vol 40 (3) ◽  
pp. 487-492
Author(s):  
J. A. RIEGEL
Keyword(s):  
Osmotic Pressure ◽  
Freezing Point ◽  
Chloride Concentration ◽  
Distal Tubule ◽  
Freezing Point Depression ◽  
Antennal Gland ◽  
Marked Drop

1. Chloride concentration and freezing-point depression ( =osmotic pressure) have been measured on samples of urine obtained from various parts of the crayfish antennal gland by micropuncture. 2. The chloride concentration of the urine is significantly below that of the blood in all parts of the antennal gland, but a marked drop is not seen until the distal tubule is reached. 3. The urine becomes progressively hypo-osmotic to the blood in the labyrinth, distal tubule and bladder. In the coelomosac, it is iso-osmotic; possible reasons for this are discussed. 4. Chloride concentration and osmotic pressure are lower in urine taken from the nephropore than in urine taken from the distal tubule near the place where it joins the bladder. This suggests that the bladder is in part responsible for the production of hypotonic urine. 5. The results of the present study are discussed in relation to the theory that filtration (in the limited sense discussed by Riegel & Kirschner, 1960) is the mechanism by which primary urine is formed in the crayfish antennal gland.

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