Cellular digestion : its utility in pathological processes / by N.S. Davis, jr.

  • Davis, N. S. (Nathan Smith), 1858-1920.
Date:
[1887?]
Catalogue details

Licence: Public Domain Mark

Credit: Cellular digestion : its utility in pathological processes / by N.S. Davis, jr. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    hours old the bacilli had become finely granular, many even mere granules or short, glistening, often irregularly formed rings. They were no longer capable of cultivation nor toxic to mice. Living bacilli were found very exceptionally in older pus. In reply to the query whether the bacilli had not been first swallowed and destroyed by the pus cells, and subsequently disgorged, the author urged the lesson of the following experiment. If pus containing liviug bacilli is sealed in a tube that is kept at 36° C. from forty-eiglit to seventy-two hours the changes above described will take place, but if bacilli growing in bouillon is similarly treated, tliey lose neither life nor toxicity. He supposed that the pus cells cease to be active, liviug factors when thus treated. It is evident, however, that the richly cellular pus is inimical to the bacilli, and probably if the cells are not their destroyers, something resulting from the presence of the cells is. While calling attention to the utility of intra-cellular digestion in pathological pro- cesses, I have mentioned only the white blood cells as possessing the power. Undoubt- edly connective tissue cells and granulation tissue cells, or embryonic cells, also possess it, and probably some forms of tumor cells. It is a well-known fact that inflamed or dead bone will undergo absorption unless suppuration intervenes. Numerous theories have been propounded to explain the phe- nomena. Rindfieiscli has suggested that the blood in the congested vessels contains an excess of carbonic acid, which may dissolve the lime salts, forming an acid carbonate.* Others have supposed that lactic acid is formed, which produces a soluble calcic sarco- lactate. These hypotheses are improbable, for bone exposed indefinitely to the influ- ences of purulent inflammation loses little of its substance and its surface may remain smooth. Virchow believes that cells derived from proliferation of bone corpuscles are the active agents. There is little doubt that the living cells which surround or perme- ate bone when it is undergoing absorption are the active factors in its removal, although most pathologists do not wholly agree with Virchow as to their origin. Usually the absorption power is ascribed to granulation cells or to osteoclasts, both of which origi- nate from leucocytes. To illustrate, recall the appearance of the changes that occur in rarefying osteitis. The bone is indented by deep or shallow, simple or complex depres- sions that are filled with cells of varying size. These cells originate as do granulation cells, but among them giant cells are oftener found than in ordinary granulations. Frequently they are continuous with or outgrowths of neighboring granulation tissue. These so-called osteoclasts fill the pockets in the bone, which so evidently melts before their encroachments that no one can doubt their activity in its removal. It is literally eaten away by them. Tumor cells are so various in character that we cannot affirm of all kinds digestive power, but some undoubtedly possess this function. The cells of infiltrating tumors have absorptive powers. This capability is most noticeable when bone is involved, for then the hard, compact bone is readily seen to have disappeared and to have been replaced by the new tumor tissue. When tumor cells infiltrate other tissues, the normal cells are seen to undergo atrophy and to finally disappear and be replaced by the tumor structures. This process is ordinarily explained by assigning to the growing tumor a mechanical power of interfering with the blood supply of the neighboring tissue, and therefore inducing atrophy. However, the disappearance of inert lime deposits in bone can scarcely be explained in this way. The influence of the contact of active, growing cells seems moie important. Can living cells render solid materials soluble by simple contact with them ? There is little doubt that intra-cellular digestion takes place. But in the absorption of bone there is no evidence that particles of it are first detached, swallowed and then digested by the osteoclasts. On the contrary, the latter apparently erode it by their contact. * Pepper, A. J., “ Surgical Pathology,” p. 234.