1
342 considerable attention, due often to substances, notably alkalis, used to clean the skin after work ; they dissolve the grease which holds the superficial skin cells together, leaving the ubiquitous germ to penetrate to the relatively unprotected deeper layers. Other cases originated from oil and " suds " in engineering. A clean skin and an emollient applica- tion prevent these troubles. The general impression to be gained from reading the report is that health depends far more than is often thought upon the way life is lived, and that sickness and disease are earned by exposure to faulty environment. THE JAW-WINKING PHENOMENON. THERE is an anomaly, first noticed in 1883 by the late Mr. Marcus Gunn, which affects certain people, most of whom have a partial congenital ptosis, generally unilateral. It is noticed that in these people, when the mouth is opened, and especially when the lower jaw is turned to the same side as the eye with ptosis, that eye is opened ; when the mouth is closed the lid falls again. A. Leri and J. Weill have lately reported this anomaly in two patients-a mother and son-and this is interesting because a familial inci- dence has rarely been noted before. In the mother the affection was bilateral, which is also very exceptional. The son had facial asymmetry, with partial atrophy of the side affected with ptosis. A similar facial asymmetry was seen in a daughter also (third generation) but she did not show the jaw- winking phenomenon. As regards causation, the explanation which has obtained most acceptance is that of Mr. Bishop Harman,2 who attributes the condition to atavism. He points out that the first gill-slit or " spiracle " of fishes, which is homologous with the human external auditory meatus, is sur- rounded by a deep and also by a superficial muscle. The deep muscle extends to the lower jaw which it depresses, and is homologous with the external pterygoid in man. The superficial one closes the orifice of the spiracle and also extends to the upper eye-lid which it closes. These two muscles are antagonistic. Anyone who watches fishes in an aquarium will see that when a fish opens its mouth the operculum covering its gills swings open too. In the same way when one of the subjects of this anomaly opens his mouth the orbiculus palpebrarum ceases to act, and the levator, though generally weak in these cases, has it all its own way. This is the explanation which finds favour in England, but the French authors we have mentioned are not satisfied with it, and prefer to regard the phenomenon as a " functional association " analogous to those seen in some cases of hemiplegia. GROWTH-INHIBITING SUBSTANCES. SUBSTANCES-or supposed substances-which encourage growth have become very familiar in recent years. The tissue-culturist adds embryo extract to get the tissues to grow in vitro, the nutritionist gives the observed rats vitamins. The assumption is made with considerable regularity that failure to grow is due to the absence of something which promotes growth rather than to the presence of something which retards or inhibits growth. The demonstration of growth-inhibiting substances in animal and vegetable tissues is therefore of rather particular interest and may have far-reaching implications. Dr. T. B. Heaton, of Oxford, showed some time since that extracts of animal organs had a thermostable property (conveniently spoken of as a substance) of selectively inhibiting the growth of fibroblasts from fowl embryos in tissue cultures ; on the growth of epithelium from the skin or bowel it had no influence. He now (Journal of Pathology and Bacteriology, 1929, xxxii.. 1 Bull. de la Soc. Méd. des Hôp. de Paris, July 8th, p. 875. 2 Trans. Ophthal. Soc., 1903, xxiii., 356. 565) follows this idea, out in greater detail. All tissue growth in vertebrates depends on the coordinated and commensurate growth of the connective tissue with its blood-vessels. A substance which obstructs the growth of fibrous tissue should therefore impede growth as a whole. He shows that from animal tissues yeast and especially malt extracts may be made which delay the metamorphosis of tadpoles and the regeneration of amputated parts in newts; given intraperitoneally to young rats they cause immediate cessation of growth which is resumed when the dosingis omitted; pregnant guinea-pigs stop increasing in weight and abort. These are the general results of extracts which are active in preventing the growth of fibroblasts in tissue cultures ; extracts which are negative to this test have no effect in the whole animal. Analogous experiments with the Jensen rat sarcoma gave similar results, the tumours ceasing to grow, and in some instances being completely absorbed. Dr. Heaton’s observations are not perhaps in all instances as ample as might be wished, but they seem to open the way to an interesting and important line of inquiry. ____ THE LESIONS OF ACUTE RHEUMATISM, Dr. A. F. Bernard Shaw has just published some valuable histological researches on the lesions of acute rheumatism. The source of the material was a girl of 15 who died from rheumatic fever and chorea. The exhaustive pathological and histological study made of this case is recorded in minute detail with many illustrations in the current issue of the Archives of Diseases in Children. Dr. Bernard Shaw shows that the virus of rheumatic infection has a predilection for connective tissue. The initial lesion there is a necrosis of the collagen followed by a focal infiltration with mobile cells including lymphocytes, plasma cells, macrophages, and many polymorphonuclears. The process is well seen in the Aschoff nodes in the myocardium, but is by no means uncommon in such widely different places as the tendinous slips of muscle, aponeurotic tissues, and arterial adventitia. The lesions in the walls of the nutrient arteries of the heart valves, coupled with those primarily in the connective tissue of the valves themselves, bring about a condition of valvulitis which may exist-and on the right side of the heart probably often does exist-without actual break of endocardial continuity. Valvulitis is, of course, often a precursor of endocarditis. The liability of a purely valvular lesion to advance to endocarditis depends on the degree of circulation of the virus permitted within the valve by its intrinsic arterial tree and the amount of mechanical stress to which the valve is exposed. Anatomical research on the intrinsic vascularity of the valves and physical assessment of the stresses to which each is exposed would lead to the theoretical assumption that endo- carditis would involve the valves in the following order of frequency-mitral, aortic, tricuspid, pulmonary. This is the precise order of frequency found in practice, and therefore the suggestion that endocarditis is partly due to advancing valvulitis, caused by intrinsic arterial and connective tissue lesions, and is not transmitted only through the blood. is well supported. In addition to discussions on the mechanism of the production of rheumatic endocarditis Dr. Bernard Shaw gives full and new descriptions of the wide- spread local manifestations of the general rheumatic infection in the heart muscle, the brain and meninges, the serous membranes, the muscles, the visceral arteries and veins, and the lymphoid tissue. Generally speaking, the brunt of the attack is borne in the first place by the connective tissue which presents focal necrotic lesions as the primary event and secondary cellular infiltration leading to the formation of a node. As a result of his histological researches the author dissents from the view that a deposit of fibrin forms the essential basis of a node. He is careful to explain that valvulitis may exist without

GROWTH-INHIBITING SUBSTANCES

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considerable attention, due often to substances,notably alkalis, used to clean the skin after work ;they dissolve the grease which holds the superficialskin cells together, leaving the ubiquitous germ topenetrate to the relatively unprotected deeper layers.Other cases originated from oil and " suds " inengineering. A clean skin and an emollient applica-tion prevent these troubles. The general impressionto be gained from reading the report is that healthdepends far more than is often thought upon the waylife is lived, and that sickness and disease are earnedby exposure to faulty environment.

THE JAW-WINKING PHENOMENON.

THERE is an anomaly, first noticed in 1883 by thelate Mr. Marcus Gunn, which affects certain people,most of whom have a partial congenital ptosis,generally unilateral. It is noticed that in these people,when the mouth is opened, and especially when thelower jaw is turned to the same side as the eye withptosis, that eye is opened ; when the mouth is closedthe lid falls again. A. Leri and J. Weill have latelyreported this anomaly in two patients-a mother andson-and this is interesting because a familial inci-dence has rarely been noted before. In the motherthe affection was bilateral, which is also veryexceptional. The son had facial asymmetry, withpartial atrophy of the side affected with ptosis. Asimilar facial asymmetry was seen in a daughter also(third generation) but she did not show the jaw-winking phenomenon. As regards causation, theexplanation which has obtained most acceptance isthat of Mr. Bishop Harman,2 who attributes thecondition to atavism. He points out that the firstgill-slit or " spiracle " of fishes, which is homologouswith the human external auditory meatus, is sur-

rounded by a deep and also by a superficial muscle.The deep muscle extends to the lower jaw which itdepresses, and is homologous with the externalpterygoid in man. The superficial one closes theorifice of the spiracle and also extends to the uppereye-lid which it closes. These two muscles are

antagonistic. Anyone who watches fishes in an

aquarium will see that when a fish opens its mouththe operculum covering its gills swings open too.In the same way when one of the subjects of thisanomaly opens his mouth the orbiculus palpebrarumceases to act, and the levator, though generally weakin these cases, has it all its own way. This is theexplanation which finds favour in England, but theFrench authors we have mentioned are not satisfiedwith it, and prefer to regard the phenomenon as a" functional association " analogous to those seen insome cases of hemiplegia.

GROWTH-INHIBITING SUBSTANCES.

SUBSTANCES-or supposed substances-whichencourage growth have become very familiar in recentyears. The tissue-culturist adds embryo extract toget the tissues to grow in vitro, the nutritionist givesthe observed rats vitamins. The assumption is madewith considerable regularity that failure to grow isdue to the absence of something which promotesgrowth rather than to the presence of something whichretards or inhibits growth. The demonstration ofgrowth-inhibiting substances in animal and vegetabletissues is therefore of rather particular interest andmay have far-reaching implications. Dr. T. B.Heaton, of Oxford, showed some time since thatextracts of animal organs had a thermostable property(conveniently spoken of as a substance) of selectivelyinhibiting the growth of fibroblasts from fowl embryosin tissue cultures ; on the growth of epithelium fromthe skin or bowel it had no influence. He now(Journal of Pathology and Bacteriology, 1929, xxxii..

1 Bull. de la Soc. Méd. des Hôp. de Paris, July 8th, p. 875.2 Trans. Ophthal. Soc., 1903, xxiii., 356.

565) follows this idea, out in greater detail. Alltissue growth in vertebrates depends on the coordinatedand commensurate growth of the connectivetissue with its blood-vessels. A substance whichobstructs the growth of fibrous tissue should thereforeimpede growth as a whole. He shows that fromanimal tissues yeast and especially malt extractsmay be made which delay the metamorphosis oftadpoles and the regeneration of amputated parts innewts; given intraperitoneally to young rats theycause immediate cessation of growth which is resumedwhen the dosingis omitted; pregnant guinea-pigs stopincreasing in weight and abort. These are the generalresults of extracts which are active in preventing thegrowth of fibroblasts in tissue cultures ; extracts whichare negative to this test have no effect in the wholeanimal. Analogous experiments with the Jensen ratsarcoma gave similar results, the tumours ceasing togrow, and in some instances being completely absorbed.Dr. Heaton’s observations are not perhaps in allinstances as ample as might be wished, but theyseem to open the way to an interesting and importantline of inquiry. ____

THE LESIONS OF ACUTE RHEUMATISM,

Dr. A. F. Bernard Shaw has just published somevaluable histological researches on the lesions ofacute rheumatism. The source of the material wasa girl of 15 who died from rheumatic fever and chorea.The exhaustive pathological and histological studymade of this case is recorded in minute detail withmany illustrations in the current issue of the Archivesof Diseases in Children. Dr. Bernard Shawshows that the virus of rheumatic infectionhas a predilection for connective tissue. Theinitial lesion there is a necrosis of the collagenfollowed by a focal infiltration with mobile cellsincluding lymphocytes, plasma cells, macrophages, andmany polymorphonuclears. The process is well seenin the Aschoff nodes in the myocardium, but is byno means uncommon in such widely different placesas the tendinous slips of muscle, aponeurotic tissues,and arterial adventitia. The lesions in the walls ofthe nutrient arteries of the heart valves, coupled withthose primarily in the connective tissue of the valvesthemselves, bring about a condition of valvulitiswhich may exist-and on the right side of the heartprobably often does exist-without actual break ofendocardial continuity. Valvulitis is, of course,often a precursor of endocarditis. The liability ofa purely valvular lesion to advance to endocarditisdepends on the degree of circulation of the viruspermitted within the valve by its intrinsic arterialtree and the amount of mechanical stress to whichthe valve is exposed. Anatomical research on theintrinsic vascularity of the valves and physicalassessment of the stresses to which each is exposedwould lead to the theoretical assumption that endo-carditis would involve the valves in the followingorder of frequency-mitral, aortic, tricuspid,pulmonary. This is the precise order of frequencyfound in practice, and therefore the suggestion thatendocarditis is partly due to advancing valvulitis,caused by intrinsic arterial and connective tissuelesions, and is not transmitted only through the blood.is well supported.

In addition to discussions on the mechanism of theproduction of rheumatic endocarditis Dr. BernardShaw gives full and new descriptions of the wide-spread local manifestations of the general rheumaticinfection in the heart muscle, the brain and meninges,the serous membranes, the muscles, the visceralarteries and veins, and the lymphoid tissue. Generallyspeaking, the brunt of the attack is borne in the firstplace by the connective tissue which presents focalnecrotic lesions as the primary event and secondarycellular infiltration leading to the formation of a node.As a result of his histological researches the authordissents from the view that a deposit of fibrin formsthe essential basis of a node. He is carefulto explain that valvulitis may exist without