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A DIRECT RECORD SCOTOMETER
812 The Determination of Sodium in Blood (p.312), by Edward A. Doisy and Richard D. Bell.-The method of Ball (Jour. Chem. Soc., 1910, xcvii., 1408) depending on the precipitation of sodium as
sodium caesium bismuth nitrite has been elaborated and details given for the estimation of small quantities of sodium in blood and urine by gravimetric, volumetric, and colorimetric procedure. See also Kramer (Jour. Biol. Chem., 1920, xli., 263) for method of estimation of sodium based upon the insolubility of sodium pyroantimonate.
New Inventions.
are
Absorption and Elimination of Manganese Ingested as Oxides and Silicates (p. 133), by C. K. Reiman and A. S. Minot.-The analysis of the blood of manganese workers showed no marked variation from the normal manganese content (0’012 mg. per 100 c.cm). Experimental work showed that ores containing manganese as oxides and silicates are soluble in gastric juice ; that manganese is absorbed in the blood stream causing a slight temporary rise in manganese concentration followed by a quick return to the normal. In none of the cases studied was the manganese content of the blood increased by the ingestion of manganese ores to a value more than double the normal level, and in some of the subjects no increase was noted. Prolonged feeding of large amounts of manganese ores to dogs failed to produce significant changes in the manganese content of blood and tissues or to cause pathological symptoms. Manganese ores are non-toxic, and in order to produce symptoms of poisoning must be ingested by individuals who are peculiarly susceptible ; such individuals are rare.
Gasometric Determination of Nitrogen and its Application to the Estimation of the Non-protein Nitrogen of Blood (p. 223), by R. L. Stehle.-5 or 10 c.cm. of the filtrate obtained from the blood after tungstic acid precipitation are submitted to the usual Kjeldahl digestion, after which decomposition with sodium hypobromite is carried out, and the volume of nitrogen measured. The method is stated to have certain advantages over the Kjeldahl procedure. The Iodometric Determination of Copper and its Use in Sugar Analysis!(1) Equilibria in the Reaction between Copper Sulphate and Potassium Iodide (p. 349); (2) Methods for the Determination of Reducing Sugars in Blood, Urine, Milk, and Other Solutions (p. 365), by P. A. Shaffer and A. F. Hartmann.-The reversible + I- Cu+ + 12 has been investigated and reaction applied to the determination of the mixture of cuprous and residual cupric copper resulting from the action of reducing sugar upon alkaline copper solutions. The reaction may be caused to take place to completion in either direction, thus enabling the determination by iodometric titration of the cupric or the cuprous copper in a mixture of the two forms. Details of methods for both titrations are given and their application, to the determination of reducing sugar in milk, blood, urine, and other solutions. The Estimation of the Bile Acids (p. 415), by C. L. A. Schmidt and A. E. Dart.-A method is described for the estimation of the nitrogen of bile acids of the taurine and glycocoll series. It is based on the fact that on hydrolysis with NaOH the bile acids are split giving taurine and glycocoll which react quantitatively with The taurine nitrogen can be estimated from the total HN02. sulphur-content of the protein-free bile. A Method for the Determination of Chlorine in Solid Tissues (p. 427), by R. D. Bell and E. A. Doisy.-The method depends on the rapid digestion of the tissue with concentrated sulphuric and persulphuric acid, the digestion gases being carried over by suction into alkaline sulphite solution in which the chlorine is estimated by the Van Slyke-Donleavy method. Details of technique and special apparatus used are given. Relationship between Plasma Bicarbonate and Urinary Acidity following the Administration of Sodium Bicarbonate (p. 101), by W. J. Palmer, H. Salvesen, and H. Jackson, jun.-In normal and pathological cases following the administration of sodium bicarbonate the plasma bicarbonate C02 approaches 68’7 ± 10 volumes per cent. at the time the first depressing effect of the alkali on the urinary acidity is noted. The use of the first significant effect on the pH of the urine, therefore, in controlling the therapeutic use of sodium bicarbonate, is safe and reliable, but owing to the inconstancy of the level of the plasma bicarbonate CO2 at this point the accurate estimation of the degree of diminished alkali reserve cannot be made. The observation of Palmer and Van Slyke is confirmed that " absorbed sodium bicarbonate is distributed in approximate uniformity ...... to the blood " ; and " the effect of a given dose in raising the plasma bicarbonate may be calculated by assuming that the body contains .700 c.cm. of fluid per kilo and that the bicarbonate is distributed therein uniformly." On this subject see also Calvert, Myers, and Milroy, Jour. Path. and Bact., xxiv., 91,1921.
A DIRECT RECORD SCOTOMETER FOR
INVESTIGATING
THE
CENTRAL
FIELD
OF
VISION.
VARIOUS instruments have been devised for the purpose of mapping out central nelds of vision, but the chief difficulties in this kind of perimetry have been due to the slowness of the means of taking the For the past two years I have been observations. which overcomes this difficulty. instrument an using Observations may be made quickly and accurately, and at the same time a direct record of the observations is taken. The apparatus consists of a rigid iron stand to which is fitted a frame carrying the screen against which the observations are to be made. The screen is of grey cloth, fixed into it in the central position is a small white metal stud; this is the fixation point. Behind the screen is a sheet of carbon and a paper chart, ruled for convenience in the usual degree circles and radii. Red and blue tracing papers are also supplied, which enable three records to be taken, at intervals, on the same chart. The object is carried on a suitable object holder and held in the surgeon’s hand, which is obscured from the patient’s view by a grey cloth bag-glove. At the back of the
Cu++
Relation of the Alkali Reserve of the Blood to Glycosuria and Hyperglycæmia in Pancreatic Diabetes (p. 51), by B. M. Hendrix and C. Y. Crouter.-A decrease in the alkali reserve of the blood, as shown by the C02 capacity of the plasma. is not simultaneous with the appearance of hyperglycæmia and glycosuria in pancrea.tectomised dogs. A slight increase in the CO2 capacity of blood plasma was observed on the first or second day after removal of the pancreas, later decreasing and gradually reaching about 30 volumes per cent. in two cases. Definite acidosis appears comparatively late in pancreatic diabetes in dogs. Studies of the Distribution of Carbon Dioxide Between Cells and Plasma (p. 245), by L. W. Smith, J. H. Means, and M. N. Woodwell. -From the investigation of the C02 content of the whole blood and plasma of both venous and arterial blood it has been found that as the blood passes from the arterial to the venous side of the circulation in normal man its corpuscles gain from 4 to 11 volumes per cent. of CO2; the corresponding gain in the plasma is only from 0’0 to 1’8 volumes per cent., and the conclusion is drawn, therefore, that the transport of C02 is accomplished mainly by the corpuscles. The same holds true in anaemia and certain other diseases, although the actual distribution of C02 between cells and plasma is
altered.
frame knobs are fixed in the usual positions of the blind spots, so that the surgeon has a reliable guide from which to work. In taking observations the patient’s face at the naso-buccal groove is pressed against the knob on the free upright of the stand. One eye is covered, the other looks at the fixation spot. The surgeon moves the object over those parts of the field he desires and notes when the patient sees it and when he does not. The records of the observations are made by pressing the small style on the back of the object holder against the screen, when the impress is conveyed by the carbon sheet to the chart. The whole of the movements of the object over the screen may be traced in this fashion by a light continuous pressure and salient points marked by deeper pressure. The real advantage of this recording instrument is the speed and accuracy with which observations may be made. If the surgeon has to move about, take notes, shift the instrument, or do anything that takes time or diverts the patient’s attention, accuracy of observation is diminished or indeed may be lost entirely. The instrument has been well made by Messrs. John Weiss and Son, Ltd.,.of 287, Oxford-street, London, W. 1. N. BISHOP HARMAN, M.B., B.C. Cantab., F.R.C.S. Eng.
sodium caesium bismuth nitrite has been elaborated and details given for the estimation of small quantities of sodium in blood and urine by gravimetric, volumetric, and colorimetric procedure. See also Kramer (Jour. Biol. Chem., 1920, xli., 263) for method of estimation of sodium based upon the insolubility of sodium pyroantimonate.
New Inventions.
are
Absorption and Elimination of Manganese Ingested as Oxides and Silicates (p. 133), by C. K. Reiman and A. S. Minot.-The analysis of the blood of manganese workers showed no marked variation from the normal manganese content (0’012 mg. per 100 c.cm). Experimental work showed that ores containing manganese as oxides and silicates are soluble in gastric juice ; that manganese is absorbed in the blood stream causing a slight temporary rise in manganese concentration followed by a quick return to the normal. In none of the cases studied was the manganese content of the blood increased by the ingestion of manganese ores to a value more than double the normal level, and in some of the subjects no increase was noted. Prolonged feeding of large amounts of manganese ores to dogs failed to produce significant changes in the manganese content of blood and tissues or to cause pathological symptoms. Manganese ores are non-toxic, and in order to produce symptoms of poisoning must be ingested by individuals who are peculiarly susceptible ; such individuals are rare.
Gasometric Determination of Nitrogen and its Application to the Estimation of the Non-protein Nitrogen of Blood (p. 223), by R. L. Stehle.-5 or 10 c.cm. of the filtrate obtained from the blood after tungstic acid precipitation are submitted to the usual Kjeldahl digestion, after which decomposition with sodium hypobromite is carried out, and the volume of nitrogen measured. The method is stated to have certain advantages over the Kjeldahl procedure. The Iodometric Determination of Copper and its Use in Sugar Analysis!(1) Equilibria in the Reaction between Copper Sulphate and Potassium Iodide (p. 349); (2) Methods for the Determination of Reducing Sugars in Blood, Urine, Milk, and Other Solutions (p. 365), by P. A. Shaffer and A. F. Hartmann.-The reversible + I- Cu+ + 12 has been investigated and reaction applied to the determination of the mixture of cuprous and residual cupric copper resulting from the action of reducing sugar upon alkaline copper solutions. The reaction may be caused to take place to completion in either direction, thus enabling the determination by iodometric titration of the cupric or the cuprous copper in a mixture of the two forms. Details of methods for both titrations are given and their application, to the determination of reducing sugar in milk, blood, urine, and other solutions. The Estimation of the Bile Acids (p. 415), by C. L. A. Schmidt and A. E. Dart.-A method is described for the estimation of the nitrogen of bile acids of the taurine and glycocoll series. It is based on the fact that on hydrolysis with NaOH the bile acids are split giving taurine and glycocoll which react quantitatively with The taurine nitrogen can be estimated from the total HN02. sulphur-content of the protein-free bile. A Method for the Determination of Chlorine in Solid Tissues (p. 427), by R. D. Bell and E. A. Doisy.-The method depends on the rapid digestion of the tissue with concentrated sulphuric and persulphuric acid, the digestion gases being carried over by suction into alkaline sulphite solution in which the chlorine is estimated by the Van Slyke-Donleavy method. Details of technique and special apparatus used are given. Relationship between Plasma Bicarbonate and Urinary Acidity following the Administration of Sodium Bicarbonate (p. 101), by W. J. Palmer, H. Salvesen, and H. Jackson, jun.-In normal and pathological cases following the administration of sodium bicarbonate the plasma bicarbonate C02 approaches 68’7 ± 10 volumes per cent. at the time the first depressing effect of the alkali on the urinary acidity is noted. The use of the first significant effect on the pH of the urine, therefore, in controlling the therapeutic use of sodium bicarbonate, is safe and reliable, but owing to the inconstancy of the level of the plasma bicarbonate CO2 at this point the accurate estimation of the degree of diminished alkali reserve cannot be made. The observation of Palmer and Van Slyke is confirmed that " absorbed sodium bicarbonate is distributed in approximate uniformity ...... to the blood " ; and " the effect of a given dose in raising the plasma bicarbonate may be calculated by assuming that the body contains .700 c.cm. of fluid per kilo and that the bicarbonate is distributed therein uniformly." On this subject see also Calvert, Myers, and Milroy, Jour. Path. and Bact., xxiv., 91,1921.
A DIRECT RECORD SCOTOMETER FOR
INVESTIGATING
THE
CENTRAL
FIELD
OF
VISION.
VARIOUS instruments have been devised for the purpose of mapping out central nelds of vision, but the chief difficulties in this kind of perimetry have been due to the slowness of the means of taking the For the past two years I have been observations. which overcomes this difficulty. instrument an using Observations may be made quickly and accurately, and at the same time a direct record of the observations is taken. The apparatus consists of a rigid iron stand to which is fitted a frame carrying the screen against which the observations are to be made. The screen is of grey cloth, fixed into it in the central position is a small white metal stud; this is the fixation point. Behind the screen is a sheet of carbon and a paper chart, ruled for convenience in the usual degree circles and radii. Red and blue tracing papers are also supplied, which enable three records to be taken, at intervals, on the same chart. The object is carried on a suitable object holder and held in the surgeon’s hand, which is obscured from the patient’s view by a grey cloth bag-glove. At the back of the
Cu++
Relation of the Alkali Reserve of the Blood to Glycosuria and Hyperglycæmia in Pancreatic Diabetes (p. 51), by B. M. Hendrix and C. Y. Crouter.-A decrease in the alkali reserve of the blood, as shown by the C02 capacity of the plasma. is not simultaneous with the appearance of hyperglycæmia and glycosuria in pancrea.tectomised dogs. A slight increase in the CO2 capacity of blood plasma was observed on the first or second day after removal of the pancreas, later decreasing and gradually reaching about 30 volumes per cent. in two cases. Definite acidosis appears comparatively late in pancreatic diabetes in dogs. Studies of the Distribution of Carbon Dioxide Between Cells and Plasma (p. 245), by L. W. Smith, J. H. Means, and M. N. Woodwell. -From the investigation of the C02 content of the whole blood and plasma of both venous and arterial blood it has been found that as the blood passes from the arterial to the venous side of the circulation in normal man its corpuscles gain from 4 to 11 volumes per cent. of CO2; the corresponding gain in the plasma is only from 0’0 to 1’8 volumes per cent., and the conclusion is drawn, therefore, that the transport of C02 is accomplished mainly by the corpuscles. The same holds true in anaemia and certain other diseases, although the actual distribution of C02 between cells and plasma is
altered.
frame knobs are fixed in the usual positions of the blind spots, so that the surgeon has a reliable guide from which to work. In taking observations the patient’s face at the naso-buccal groove is pressed against the knob on the free upright of the stand. One eye is covered, the other looks at the fixation spot. The surgeon moves the object over those parts of the field he desires and notes when the patient sees it and when he does not. The records of the observations are made by pressing the small style on the back of the object holder against the screen, when the impress is conveyed by the carbon sheet to the chart. The whole of the movements of the object over the screen may be traced in this fashion by a light continuous pressure and salient points marked by deeper pressure. The real advantage of this recording instrument is the speed and accuracy with which observations may be made. If the surgeon has to move about, take notes, shift the instrument, or do anything that takes time or diverts the patient’s attention, accuracy of observation is diminished or indeed may be lost entirely. The instrument has been well made by Messrs. John Weiss and Son, Ltd.,.of 287, Oxford-street, London, W. 1. N. BISHOP HARMAN, M.B., B.C. Cantab., F.R.C.S. Eng.