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Rh outbreak of the World War Gen. Dubail took over the I. Army, which (with the II. Army under Gen. de Castelnau on the left) was responsible for the offensive into Lorraine, and later for the defence of the eastern fortress line against the armies of Prince Rupprecht of Bavaria. The stubborn resistance of Dubail and Castelnau not only nullified the threat of invasion but insured a pivot for future French manoeuvres; it prepared the way indeed for the Marne vic- tory. Gen. Dubail was given the Grand Cross of the Legion of Honour (Sept. 18 1914). On the withdrawal of the II. Army to the Somme, Dubail took charge of the whole line between Verdun and the Vosges, and when in Jan. 1915 the armies along the front were grouped under three headquarters of groups of armies, Dubail was placed in charge of that of the east, com- prising the III. of Verdun, his old I., and the Vosges force. In Oct. of the same year he was awarded the medaille militaire. On April 6 1916 he was made military governor of Paris. He was placed in the " Second Section " on reaching the age limit in April 1916, but retained his appointment as military governor of Paris. After his final retirement he was appointed Grand Chancellor of the Legion of Honour. DUCLAUX, AGNES MARY F. (1856- ), Anglo-French poet and critic (see 8.632), published after 1910 a volume of essays, The French Ideal (1911); a study of Madame de Sevigne (1914); A Short History of France (1918); Twentieth Century French Writers (1920) and a life of Victor Hugo (1921). DU CROS, WILLIAM HARVEY (1846-1918), British manu- facturer, of Huguenot descent, was born in co. Kildare, Ireland, June 19 1846. He was educated at the King's hospital, Dublin, and became founder of the pneumatic tire industry and a pioneer in automobile construction. From 1906-8 he represented Hast- ings in the House of Commons. He died at Dalkey, co. Dublin, Dec. 21 1918. DUCTLESS GLANDS (see 8.633). Much new work on the physiology, pathology and medicine of the ductless glands has been done since 1910.

There are two ways in which the consensus partium in the animal economy is brought about. The best known of these is that which occurs through the nervous system. But it has been recognized during recent years that other agents take part in this process of coordination. These are called the ductless glaruLs through their products the internal secretions, which have also been called hormones. The latter have, however, been renamed autocoid substances by Schafer, and these again divided into two groups: those which excite metabolic processes and those which depress them. The former autocoids are called by him hormones, the latter chalones.

In the glands of internal secretion, or as they are sometimes called the endocrine organs, the material secreted is passed away not through a duct but by means of the veins leaving the organ. This material when it reaches the general blood stream acts in the manner of a chemical messenger, or of a drug, producing effects upon various organs and tissues of the body. The ductless glands which we shall have to consider are (i) the adrenal gland; (2) the thyroid gland; (3) the parathyroid glandules; (4) the pituitary body; (5) the pineal gland. It is probable that the thymus is not an organ of internal secretion. In addition to these certain other glands furnished with a duct and providing an ordinary or external secretion are supposed to supply the body with internal secretions also. This applies to the pancreas. Further, the gonads (reproductive organs) have an endocrine function.

The Adrenal Gland. For many years it has been customary to refer to the cortex and the medulla of the adrenal body as the suprarenal capsule. But comparative anatomical studies have shown us that this is an inaccurate view of the problem. It is only in mammals that the terms cortex and medulla as applied to the two parts of the organ are strictly appropriate. In elas- mobranch fishes we have to deal with a series of paired chroma- phil bodies in connexion with the sympathetic ganglia, and with an interrenal body placed in the middle line between the two halves of the kidney. The first of these is the homologue of the mammalian medulla while the interrenal body corresponds to the

mammalian cortex. Even in mammals a trace of the original arrangement still persists, e.g. the sympathetic ganglia contain groups of chromaphil cells and there are other outlying masses of chromaphil tissue. The cortex also is not the sole representative in mammals of the original interrenal body. So that the problem before us is by no means to discover the function of a single organ but to ascertain the significance of the chromaphil tissues (of which the adrenal medulla is only a part) and of the cortical tissues (of which the adrenal cortex is only a part, albeit the principal one).

The chromaphil tissues everywhere contain adrenin, the formula for which is:

HO

^>CH (OH). OH 2. NH. CH 3

This substance is generally supposed to constitute the internal secre- tion of these tissues. When injected into the circulation of a living animal it produces effects similar to those brought about by stimula- tion of the sympathetic nervous system. That is to say, its action is sympathomimettc. Other substances having a similar chemical constitution will produce similar physiological effects. The most striking of such effects are constriction of arterioles and an enormous rise of blood pressure, dilatation of the pupil and inhibition of the muscular coats of the alimentary canal. Small doses often produce results qualitatively different from medium or large doses.

The secretion of the chromaphil tissues does not appear to be essential to life. It is tolerably certain that it does not help to main- tain the normal blood pressure. It is possible that it is important for the activity of muscular structures under circumstances of physiological and especially of emotional emergency.

Of the functions of the cortex we know practically nothing, and yet we are justified in regarding this portion as the adrenal body in the true sense of the word. Experimental and clinical evidence has taught us that it is the part which is essential to life. It seems prob- able that it has to do with the development of the organs of re- production. Tumors of the adrenal cortex are frequently associated with sexual precocity in young children.

The only disease definitely traceable to a lesion of the adrenal body is that known since 1855 as Addison's disease. The most strik- ing symptoms are a peculiar bronzing of the skin, extreme muscular weakness, low blood pressure, vomiting and other symptoms probably referable to the sympathetic nervous system. The patho- genesis of the skin pigmentation cannot be correlated with anything we know of the physiology of the gland. The muscular weakness is supposed to be pathognomic and attributable to the absence of circulating adrenin. The cases are always fatal, and treatment with adrenal substance seems to be of no use.

The Thyroid Gland. The thyroid is developed as an out- growth of the embryonic pharynx between the first and second branchial clefts. It is at first single and solid, but later becomes bilateral aud divided up into closed vesicles. It is doubtful how far the lateral rudiments or post-branchial bodies take part in the formation of the mature thyroid in mammals. The vesicles hold a peculiar " colloid " material which contains iodine. The blood supply is very rich and nerves are provided from both vagus and the sympathetic.

Extirpation of the thyroid produces varying results according to the kind of animal employed and according to its age. The symptoms are not always very clearly defined, but they consist in general terms of the manifestations of sluggish metabolism. In young animals there may be almost complete cessation of growth though there is a tendency to adiposity. The symptoms differ from those of myxoedema in the human subject.

DISEASES OF THE THYROID. Myxoedema. This condition is found in middle-aged or elderly subjects, usually women. The skin becomes altered, hands and feet swollen, lips and tongue en- larged. The oedema does not put on pressure, and there is mental dullness. The symptoms are in fact those of pronouncedly slowed metabolism. The disease is clearly due to deficient thyroid secre- tion, and may be kept in abeyance or permanently cured by treat- ment with thyroid substance.

Cretinism. This is usually due to atrophy of the gland at the time of birth. The growth of the skeleton is arrested and the nutri- tion of the muscles and skin is seriously affected, so that the children are deformed, and, as a result of lack of mental development, idiotic. Treatment with thyroid substance is often beneficial.

Simple Goitre. The precise pathological condition varies in different cases. The commonest form is now very generally con- sidered to be due to an infection from drinking-water. Many cases can be cured by treatment with intestinal antiseptics and steriliza- tion of the water. Small doses of iodides have been found useful as a prophylactic when administered to children in goitrous districts.