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THE INTERNAL ENVIRONMENT
794
ANNOTATIONS THE INTERNAL ENVIRONMENT
Bourdillon1 has given a local habitation and another name—interstitial cell fluid-to Claude Bernard’s milieu interne. This is the natural outcome of much recent work on the permeability of cell membranes and the distribution of water and salts in the body. The best known exposition of the trend of this type of research and of its importance to the human subject is probably the monograph by J. P. Peters.2 The thesis is briefly that the fluid in the body can be apportioned between the blood, the intercellular spaces and the cells themselves about in the proportions 9 : 15 : 76. The osmotic pressure of these subdivisions is identical. They are, however, demarcated from one another by physiological boundaries. Thus the walls of the blood capillaries appear relatively impermeable to protein, and this fact determines the partition of volume between plasma and interstitial cell fluid, which, apart from their protein content, are the same. An animal whose plasma is deproteinised shows a relative increase in the volume of intercellular fluid (oedema) for there is no longer any osmotic force to prevent the blood-pressure from forcing the plasma through the capillary walls which are freely permeable to all its remaining constituents. This is in accordance with Starling’s work of 45 years ago. As far as they affect the cells of the body, the plasma and intercellular fluid may be regarded as one, the plasma proteins being the means of keeping part of the whole in a system of patent channels through which a rapid flow, and therefore a thorough " stirring," can take
place. The boundary between this internal environment and the cells of the body which it bathes is more important than was formerly thought. The cell membrane appears in a broad sense to be impermeable to nearly all ions, such potassium, calcium, magnesium, phosphate and protein as the cells contain being prevented from leaving and sodium and chloride from entering. Osmotic equilibrium is probably achieved by the transfer of water and bicarbonate ions. Nutrition and metabolism require the passage of certain substances, and glucose and urea, for instance, Even the inorganic ions are known to pass freely. mentioned must presumably be subject to some longterm metabolic exchange. Nevertheless, there are good grounds for believing that one may regard the "body itselfas consisting of the cells and intracellular fluid and as bathed by an " internal environment" of intercellular fluid. This in turn, through its bloodplasma moiety, is in contact with the external environment via the gut, lungs and kidneys. By introducing substances into the plasma which cannot diffuse into the cells of the body and measuring their subsequent concentration, the effective volume of the milieu interne This lends it a quantitative aspect can be determined. which may be of great importance for therapeutics, although the details of its behaviour have not yet been
fully explained. HEALTH
IN
ICELAND
JUDGING from the latest reportthe people of Iceland -numbering some 117,000 of whom nearly a third live in the town of Reykjavik-enjoy good medical services and good health, and it is to be hoped that they may be left in peace to develop the former and main1. Bourdillon, J. Pr. méd. Feb. 7, 1940, p. 164. 2. Peters, J. P. Body Water, London, 1935. 3. Public Health in Iceland in 1937. Pp. 175. With summary.
tain the latter. The crude death-rate of 11’2 per 1000 living in 1937 was slightly above that of the previous year but the rise may be attributed to the influenza epidemic rather than to the reported poor economic conditions. This epidemic led to nearly or notifications 22,000 approximately 1 in 5 of the population, an extraordinarily high incidence, and is said to havebeen the most fatal since 1918. Indeed, most of the infectious diseases show remarkable yearly variations and epidemiologists may feel tantalised at being limited in the account of them to the short English summary. For instance, in the past ten years the annual cases of measles have varied between none in 1933 and 1934 and 8245 in 1936; in 1929-30 there were nearly 3000 cases of mumps while in the six years 1932-37 there have been only 26 all told; in 1935 there were 8267 cases of whooping-cough, whereas in 1937 there were none. A susceptible population is, it seems, repeatedly built up anew. Diphtheria, however, shows a much less dramatic change, from a minimum of 1 case to a maximum of 68, but relatively wide swings are also shown by acute tonsillitis, scarlet fever, epidemic catarrhal jaundice, and acute poliomyelitis. It is interesting to note the suggestion of a secular change in the incidence of acute rheumatism. In 1928 there were 88 cases while in 1929 and 1930 the figure rose to over 200; since then the level has slow-lv declined to 90-100 in 1936 and 1937. Tuberculosis has been the subject of special attack since 1935 and the results are shown in the decline both of notifications and of deaths. The number of patients with leprosy has likewise been steadily falling, and this year’s figure of 24 is the lowest on record. A record infant-mortality rate was also set up-33 deaths per 1000 livebirths-a figure of which any community might well be proud. One factor may be that 87 per cent. of the infants are reported to be breast-fed. The stillhirth-rate of 24 per 1000 fatal births is substantially below the level of 40 customary in England and Wales. Artificial abortions were legalised under the Birth Control Act of 1935 and in 1937 37 took place (in 1936 there were 32). In 11 of these social as well as health factors were taken into consideration. PRESENT STATUS OF ELECTROCARDIOGRAPHY
CLINICAL electrocardiography has run the familiar of medical innovations. Originally used by a select few as a means of investigating certain of the arrhythmias, its existence gradually became more widely known until in the years following the last war it was being used by all and sundry without much discrimination. Lately the pendulum has swung so far in the opposite direction that many sound clinicians have relegated the electrocardiograph to an insignificant position in their diagnostic amnamentarium, though according to Willius1 the apparatus is still abused on the other side of the Atlantic. Of its value in the diagnosis of the arrhythmias there can be no question. Here it has entirely replaced the polygraph as the final court of appeal. In other forms of heart disease, particularly in myocardial and coronary lesions, its place is not so certain. In his monograph on electrocardiographic patterns Barnes of the Mayo Clinic suggests that in these, although isolated electrocardiograms may be useful, accurate information can often only be obtained from serial records. Inversion
course
1. 2. an
English
Willius, F. A. Proc. Mayo Clin. 1940, 15, 143. Electrocardiographic Patterns. Their Diagnostic and Clinical Significance. By Arlie R. Barnes, M.D. London: Baillière, Tindall and Cox. 1940. Pp. 197. 27s. 6d.
ANNOTATIONS THE INTERNAL ENVIRONMENT
Bourdillon1 has given a local habitation and another name—interstitial cell fluid-to Claude Bernard’s milieu interne. This is the natural outcome of much recent work on the permeability of cell membranes and the distribution of water and salts in the body. The best known exposition of the trend of this type of research and of its importance to the human subject is probably the monograph by J. P. Peters.2 The thesis is briefly that the fluid in the body can be apportioned between the blood, the intercellular spaces and the cells themselves about in the proportions 9 : 15 : 76. The osmotic pressure of these subdivisions is identical. They are, however, demarcated from one another by physiological boundaries. Thus the walls of the blood capillaries appear relatively impermeable to protein, and this fact determines the partition of volume between plasma and interstitial cell fluid, which, apart from their protein content, are the same. An animal whose plasma is deproteinised shows a relative increase in the volume of intercellular fluid (oedema) for there is no longer any osmotic force to prevent the blood-pressure from forcing the plasma through the capillary walls which are freely permeable to all its remaining constituents. This is in accordance with Starling’s work of 45 years ago. As far as they affect the cells of the body, the plasma and intercellular fluid may be regarded as one, the plasma proteins being the means of keeping part of the whole in a system of patent channels through which a rapid flow, and therefore a thorough " stirring," can take
place. The boundary between this internal environment and the cells of the body which it bathes is more important than was formerly thought. The cell membrane appears in a broad sense to be impermeable to nearly all ions, such potassium, calcium, magnesium, phosphate and protein as the cells contain being prevented from leaving and sodium and chloride from entering. Osmotic equilibrium is probably achieved by the transfer of water and bicarbonate ions. Nutrition and metabolism require the passage of certain substances, and glucose and urea, for instance, Even the inorganic ions are known to pass freely. mentioned must presumably be subject to some longterm metabolic exchange. Nevertheless, there are good grounds for believing that one may regard the "body itselfas consisting of the cells and intracellular fluid and as bathed by an " internal environment" of intercellular fluid. This in turn, through its bloodplasma moiety, is in contact with the external environment via the gut, lungs and kidneys. By introducing substances into the plasma which cannot diffuse into the cells of the body and measuring their subsequent concentration, the effective volume of the milieu interne This lends it a quantitative aspect can be determined. which may be of great importance for therapeutics, although the details of its behaviour have not yet been
fully explained. HEALTH
IN
ICELAND
JUDGING from the latest reportthe people of Iceland -numbering some 117,000 of whom nearly a third live in the town of Reykjavik-enjoy good medical services and good health, and it is to be hoped that they may be left in peace to develop the former and main1. Bourdillon, J. Pr. méd. Feb. 7, 1940, p. 164. 2. Peters, J. P. Body Water, London, 1935. 3. Public Health in Iceland in 1937. Pp. 175. With summary.
tain the latter. The crude death-rate of 11’2 per 1000 living in 1937 was slightly above that of the previous year but the rise may be attributed to the influenza epidemic rather than to the reported poor economic conditions. This epidemic led to nearly or notifications 22,000 approximately 1 in 5 of the population, an extraordinarily high incidence, and is said to havebeen the most fatal since 1918. Indeed, most of the infectious diseases show remarkable yearly variations and epidemiologists may feel tantalised at being limited in the account of them to the short English summary. For instance, in the past ten years the annual cases of measles have varied between none in 1933 and 1934 and 8245 in 1936; in 1929-30 there were nearly 3000 cases of mumps while in the six years 1932-37 there have been only 26 all told; in 1935 there were 8267 cases of whooping-cough, whereas in 1937 there were none. A susceptible population is, it seems, repeatedly built up anew. Diphtheria, however, shows a much less dramatic change, from a minimum of 1 case to a maximum of 68, but relatively wide swings are also shown by acute tonsillitis, scarlet fever, epidemic catarrhal jaundice, and acute poliomyelitis. It is interesting to note the suggestion of a secular change in the incidence of acute rheumatism. In 1928 there were 88 cases while in 1929 and 1930 the figure rose to over 200; since then the level has slow-lv declined to 90-100 in 1936 and 1937. Tuberculosis has been the subject of special attack since 1935 and the results are shown in the decline both of notifications and of deaths. The number of patients with leprosy has likewise been steadily falling, and this year’s figure of 24 is the lowest on record. A record infant-mortality rate was also set up-33 deaths per 1000 livebirths-a figure of which any community might well be proud. One factor may be that 87 per cent. of the infants are reported to be breast-fed. The stillhirth-rate of 24 per 1000 fatal births is substantially below the level of 40 customary in England and Wales. Artificial abortions were legalised under the Birth Control Act of 1935 and in 1937 37 took place (in 1936 there were 32). In 11 of these social as well as health factors were taken into consideration. PRESENT STATUS OF ELECTROCARDIOGRAPHY
CLINICAL electrocardiography has run the familiar of medical innovations. Originally used by a select few as a means of investigating certain of the arrhythmias, its existence gradually became more widely known until in the years following the last war it was being used by all and sundry without much discrimination. Lately the pendulum has swung so far in the opposite direction that many sound clinicians have relegated the electrocardiograph to an insignificant position in their diagnostic amnamentarium, though according to Willius1 the apparatus is still abused on the other side of the Atlantic. Of its value in the diagnosis of the arrhythmias there can be no question. Here it has entirely replaced the polygraph as the final court of appeal. In other forms of heart disease, particularly in myocardial and coronary lesions, its place is not so certain. In his monograph on electrocardiographic patterns Barnes of the Mayo Clinic suggests that in these, although isolated electrocardiograms may be useful, accurate information can often only be obtained from serial records. Inversion
course
1. 2. an
English
Willius, F. A. Proc. Mayo Clin. 1940, 15, 143. Electrocardiographic Patterns. Their Diagnostic and Clinical Significance. By Arlie R. Barnes, M.D. London: Baillière, Tindall and Cox. 1940. Pp. 197. 27s. 6d.