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SCIENCE 



iN. S. Vol. XXVII. No. 682 



diminished or increased in quantity. A 

 notable instance of this kind is found in 

 the relation of the thyroid gland to myxoe- 

 dema and to Basedow's disease. Still 

 another instance, possibly, has just been 

 mentioned in connection with the adrenal 

 gland. But in the pancreas it seems not 

 impi-obable that one and the same patho- 

 logical effect is or can be produced by 

 changes in the islands of Langerhans which 

 make for diminution of secretion, or its 

 increase, with, in the latter case, possibly, a 

 qualitative change in its chemical composi- 

 tion. That is to say, atrophy and degen- 

 eration of the islands have now been found 

 so many times in the pancreas of persons 

 succumbing to diabetes mellitus that it 

 would be accepted as a causal condition 

 were it not for the occurrence in a certain 

 number of severe and fatal clinical cases 

 of diabetes .of hypertrophy instead of 

 atrophy of the islands. Analysis of the 

 reported cases of diabetes in which the con- 

 dition of the islands of Langerhans were 

 carefully noted shows that it is in the 

 diabetes of the young especially that the 

 hypertrophied state of the islands is en- 

 countered, and the suggestion is a strong 

 one and merits careful consideration 

 whether the islands in these cases may not 

 have been imperfectly developed and have 

 yielded a secretion of such altered and 

 abnormal quality as to have been the cause 

 of the disturbance of the carbohydrate 

 metabolism leading to the fatal diabetes. 

 The conception is unusual, but it is not im- 

 possrble and is in harmony with the facts 

 so far collected. The mere fact that the 

 pancreas and the islands of Langerhans as 

 a whole are so rarely found even appar- 

 ently normal in diabetics must be accepted 

 as of great significance in respect to the 

 point as to whether, after all, alterations 

 in the islands are more than accidentally 

 connected with the disease ; for our histo- 

 logical methods are still so far from per- 



fect that subtile cellular changes, now only 

 suspected, "nill surely be discovered in the 

 future. 



In comparison with the gi-eat advances 

 already achieved in the infectious diseases 

 stands the relatively small progress made 

 in the clearing up of the etiology of the 

 more chronic diseases of the important 

 viscera. The problems of the latter have, 

 until now, except here and there, resisted 

 all effort at their solution. "What is chiefly 

 lacking to a fresh and successful endeavor 

 is a suitable and promising method of in- 

 vestigation, and we may well welcome, 

 therefore, an experimental one which aims 

 at a study of important tissues and organs 

 transferred from one animal to another of 

 the same or even of a different species, and 

 the gradual ablation or sudden increase of 

 important organs in order to establish the 

 influences exerted by a new environment ,, 

 on certain organs, or transplanted organs 

 on a new host, or the limit of destruction 

 of tissues with normal and with patho- 

 logical reactions, or the manner and degree 

 of control capable of being exercised over a 

 greatly augmented activity of different 

 organs. The technical surgical operation 

 involved in this kind of experimentation, ,; 

 on account of the necessity of maintaining 

 unimpaired the circulation of the blood, is 

 great but not impossible of achievement; 

 and the final goal is so important, involv- 

 ing as it does the possibility of substituting 

 sound for diseased organs in human beings, 

 that no effort will or should be spared to 

 reach it. 



This method of experiment has, of 

 course, nothing in common with the older 

 one of transplanting minute portions of 

 tissue from one animal to another. In 

 spite of survival of these grafts, for a time, 

 they have yielded very little of an active 

 functioning nature to the new host. By 

 the method of preservation of the circula- 

 tion through the transplanted organs their 



