Cellular toxins, or, The chemical factors in the causation of disease / by Victor C. Vaughan and Frederick G. Novy.

  • Vaughan, Victor C. (Victor Clarence), 1851-1929.
Date:
1903
Catalogue details

Licence: In copyright

Credit: Cellular toxins, or, The chemical factors in the causation of disease / by Victor C. Vaughan and Frederick G. Novy. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    clear and alkaline in reaction, was filtered and injected into animals without producing any effect. It must not be inferred from the above statements that bacteria do not produce ferments. Many of them do form both diastatic and peptic ferments, which may retain their activity after the bacteria have been destroyed; but there is no proof in any case that these ferments have a causal relation to the disease. After the disease process has been inaugurated some of these ferments probably play an important part in the production of morphological changes, the nature of which will be indicated when the different diseases are dis- cussed. (6) The microorganisms may act either directly or indirectly as ferments, splitting up complex proteids in the tissue and producing among these split products the specific poisons which induce the characteristic symptoms of the disease, and may cause death. This theory, once quite generally held, has stimulated numerous investi- gations, some of which have led to important discoveries; but at present it is safe to say that among the bacterial split products formed either in artificial culture media or in the body, there is not found one which, on account of its intensity of action or from the nature of the symptoms which it produces, can be regarded as the specific cause of any one of the infectious diseases. Moreover, it has been shown that some of the most virulent germs, as for instance, the bacillus ol tetanus, will grow and retain their virulence in artificial cultures made up principally of inorganic substances and containing only minute quantities of organic bodies of such simple construction that it must be admitted that the specific toxins of these microorganisms cannot result from their cleavage action. While we are forced to conclude that no specific toxin has been found among the cleavage products of bacteria, it is well established that certain powerful poisons originate in this way, and it will come within the scope of this treatise to deal with all substances formed by the cleavage action of bacteria, both upon the constituents of artificial culture media and within the animal body. _ ^ , . • (c) Poisons may be produced by the cellular activity of bacteria much in the same way as morphin is formed in the poppy, ihis theory supposes that the formation of bacterial toxms is a synthetical rather than an analytical, process. It is now generally believed that most, if not all, of the pathogenic microorganisms consist ot cell walls containing cell protoplasm, and that the specific toxin ^ consUt- uent of the protoplasm, and that its formation is one of the v.ta^ phenomena manifested by the organism in its Processes of grow^^ and multiplication. In some species the cell wall is not easily per- meable and the toxin is found only within the cell; ^hde in^^Jer species the toxin formed within the cell readily P«f .^^^ wall and diffuses through the culture media m artificial giowths, or