METHODS AND OBJECTS OF PREVENTIVE MEDICINE

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  • 133METHODS AND OBJECTS OF PREVENTIVE MEDICINE.

    Pharmacology and Therapeutics.BICIY, A TOXIC FERMENT CONTAINED IN CASTOR-OIL SEEDS.IT has long been known that the seeds of the castor-oil

    plant were poisonous, but the nature and properties of thetoxic principle were very imperfectly known. A good dealof light has now been thrown on the question by the pub-lication of a Dorpat graduation thesis by Dr. H. Stillmark,who has been working at the subject in Professor Kobertilaboratory. He finds that the only toxic principle con-tained in ricinus seeds is an albuminoid body, which henames "ricin," and classes amongst the so-called 11 un-formed ferments." It is unaffected by dry heat of 100 C.,but is destroyed by boiling. It acts, when administered bythe mouth or by hypodermic or intravenous injection, by pro-ducing hmorrhagic inflammation of the gastro-intestinaltract, especially and primarily affecting the small intestine,and secondarily the stomach and large intestine. It usuallyalso causes extreme fulness of the gall-bladder, probably bysetting up some obstruction of the bile-duct; frequentlyalso the bladder is found greatly distended with urine, thevesical mucous membrane being inflamed. In connexionwith these experimental results obtained by observations onanimals, it is interesting to note that jaundice and anuriahave been observed in some cases of accidental poisoning bycastor-oil seeds in the human subject. Diarrhoea is by nomeans constant, constipation having been frequently noticedboth in experimental and clinical cases. Dr. Stillmark hasnever observed the cholera stools in animals which havebeen described as occurring in cases of accidental poisoning.The drowsiness and convulsions which occurred in some ofhis experimental observations he is disposed to attribute tothrombosis of the cerebral vessels. As to the lethal dose, hefinds that for animals it is 01 milligramme per kilogramme ofbody weight when the drugisinjectedintothe veins, so thatfora man weighing 60 kilogrammes it would be 6 0 milligrammes.As drugs administered in this way are perhaps ten times asactive as when taken into the stomach, the ordinary lethaldose of ricin may probably be set down as about 60 milli-grammes, a quantity contained in ten ordinary seeds. It mustbe observed, however, that Christison once had a fatal casewhere onlv "two or three seeds had been swallowed. Thisseems to have been a very exceptional instance, as there aremany cases on record where a much larger quantity has beentaken without a fatal issue: e.g., Rapp reported a casewhere an Italian non-commissioned officer took seventeenricinus seeds, and recovered ; Bouchardat, on the otherhand, had one where a girl of eighteen ate twenty seeds,and died in five days. Experiments on the physiologicalaction of ricin showed that it possesses a peculiar effectupon blood. When this is defibrinated, ricin produces a con-glomeration of the red corpuscles, together with the forma-tion of a fibrin-like substance. When blood is freshly drawnfrom a vein ricin causes it rapidly to coagulate. Again,defibrinated blood is rendered capable of passing through afilter by ricin-that is to say, the serum passes through,leaving the red corpuscles behind ; an extremely dilutesolution is sufficient for this-1 of ricin to 60,000. Noeffect was produced by ricin on isolated nerves or onthe blood pressure, and little or none on isolated muscles oron a frogs heart prepared according to Williamss method.Other euphorbiace were examined, especially the croton-oil plant, and an identical, or at all events a similar, poisonousprinciple was found in them. It was plainly proved byDr. Stillmarks experiments that the action of castor-oil hasnothing at all to do with ricin ; also that croton-oil acid,which has been shown by Buchheim, Krich, Hirschheydt,and Kobert to exist in croton-oil seeds, is an entirely distinctbody from ricin. These seeds therefore contain two virulentout distinct poisonous principles-ricin and croton-oil acid.

    HYDRASTIS CANADENSIS.

    Dr. Schatz of Rostock recommended five years ago, atthe meeting of German naturalists at Freiburg, hydrastiscanadensis as a remedy for hypermia and chronicinflammation of the internal genital organs. Since thenthis remedy has been very frequently employed, andprivate as well as public reports testify to the certainty ofits action within reasonable limits. The want of successwhich has been observed by some medical men is, according

    to Schatz, partly due to the fact that the drug was extractedin Germany, and consequently not from the fresh plant.He has repeatedly obtained remarkably good results whenthe preparation used was the one recommended, which ismade from the fresh American plant. In cases of uterinemyoma the menses became not only less in quantity andmore regular, but lie has even seen a case where thetumour, which had previously extended up to the umbilicus,had, after the constant use of the fluid extract for abouttwo years, almost disappeared in the pelvic cavity.Schatz also confirms his former communications as to thefact that hydrastis causes no pains, but produces onlydilatation of the vessels. He does not, however, wish tosay that the drug makes all, or even most, operations formyoma unnecessary. The drug is also recommended in thetoo frequent or excessive menstruation of young girls. Thehydrastis canadensis has, however, generally to be takenfor a long time and with great regularity. Another remedywhich has also come from America is, according to Schatz,most valuable in some cases, because we have no substi-tute for it, although it cannot be nearly so often em-ployed as hydrastis. It is viburnum prunifolium, whichwas obtained from the United States. This arrests thepains that some women, who have previously aborted,are apt to have during pregnancy, and which only toooften lead to the premature expulsion of the ovum. Thisdrug also has to be taken very regularly and for a longtime, in doses of from 40 to 60 grains of the inspissatedextract. Under these circumstances, however, it cannotbe replaced by opiates or by bromide of potassium. True,the opiates cannot be entirely replaced by viburnum,especially in all cases where strong labour has actually com-menced and requires to be arrested as promptly as possible.It will be impossible in such cases to do without rest andthe recumbent position, at least for some time; and successis of course only possible if the ovum is still living, andfurther interference with it warded off. But Schatz hasseen some cases in which at the first consultation the deathof the ovum could not be assumed, and where it was retainedfor months in the uterus by means of viburnum, while itactually had been dead all the time, as was shown by itsappearance when abortion subsequently took place. Theviburnum does not set quickly or powerfully enough tobe applicable to cases of normal birth or labour comingon suddenly. Schatz cannot as yet tell how the drugacts-whether by stimulating the inhibitory nervous centreof the uterus or by paralysing its motor nerves. He thinksthe former the more probable.

    METHODS AND OBJECTS OF PREVENTIVEMEDICINE.

    THE following is an abridged report of the Presidentialaddress delivered by Dr. John C. MVail, at the fourteenthannual meeting of the Sanitary Association of Scotlandon the 4th inst. :The means for disease prevention which lie at the dis-

    posal of the modern sanitarian are both numerous and varied,and the value itself of the whole object of preventivemedicine is but seldom called in question. Broadly speak-ing, we may take it that there are three great lines ofdefence, three groups of measures belonging to preventivemedicine. These are sanitation, inoculation, and isolation.Sanitation is the first line. The word is often used to coverboth inoculation and isolation, but I wish to apply it herein a more restricted sense. Assuming the theory to becorrect that zymotic diseases are due to specific organisms,we may say that the object of sanitation in this narrowedmeaning is to produce such conditions of air, soil, andwater as shall not be consonant with the existence of theseorganisms. Such environment as is most suited to a humanbeing is least suited to his microscopic foes. The first lineof defence, in fact, is simply cleanliness - cleanliness inbreathing, eating, and drinking ; cleanliness, personal,domestic, and national. It includes many measures. Itmeans that the soil on which we construct streets and housesshall be unpolluted, that the houses themselves shall beroomy and well ventilated, and that the air which ventila-tion provides shall itself be pure. It means that the waterwe drink shall contain no germs of cholera or enteric fever,and that our food shall be clean and wholesome. It means

  • 134 METHODS AND OBJECTS OF PREVENTIVE MEDICINE.

    many Acts of Parliament-Acts relating to pollution of :river:?, to adulteration of food, to water supply, to bake-houses, to smoke abatement, to cattle diseases, to dairiesand cowsheds, to factories and workshops, to open spaces,and to public health matters of many other kinds. This,then, is our first line of defence, and the question arises,Is it not in itself sufficient ? Are all these laws and is allthis cleanliness not enough, in our own country atleast, to exterminate zymotic diseases? Unfortunatelyexperience answers No, for there are germs and germs.A few feet of pure air are enough to destroy thepoison of typhus fever, while, if Dr. Hubert Airy beright, that of diphtheria may retain its vitality for severalmiles. Typhus fever, enteric fever, and cholera may betaken as the best examples of enemies which are unable topass our first line of defence. The question as to whetherthis line will ever be rendered capable of eradicating sucha disease as small-pox is hardly a practical one. I do notsay that cleanliness has no power over it. The germs ofsmall-pox will thrive better in a dirty house