200 INANITION AND MALNUTRITION 



proliferation of neuroglia around the degenerating nerve cells. Further investi- 

 gations on the results by Nissl's method are cited by Marie ('08, '10). Roberts 

 ('12) described the degenerative changes in the nerve cells as shown by Nissl's 

 technique and by other methods. 



Parhon and Papinian ('05) applied the modified silver technique and found 

 neurofibrillar lesions in the nerve cells of the spinal cord, most pronounced in 

 the cervical region. In the lumbar and sacral regions the central neurofibrillae 

 are most affected, those in the cell periphery and processes being more resistant. 

 These results were confirmed by Valtorta ('12), Bravetta ('11), Rezza ('12) and 

 others (cited by Harris ? io). 



Harris ('10) found sclerosis of the posterior and lateral columns in 4 out of 5 

 cases of pellagra, with constant degenerative changes in the nerve cells, similar 

 to those described by earlier investigators. Anderson and Spiller ('11) con- 

 cluded that in pellagra "The degeneration is caused by some toxic or infectious 

 substance affecting all parts of the cerebrospinal axis, producing cellular degen- 

 eration and diffuse degeneration of nerve fibers in the posterior and anterolateral 

 columns." 



In the spinal cord of 16 insane pellagrins, Kozowsky ('12) found the typical 

 changes in the nerve cells, especially of the anterior horn and Clarke's column, 

 and mostly in the middle and lower segments of the cord. The lateral pyra- 

 midal tracts are most frequently involved; the posterior columns next. There 

 is increased fibrosis along the blood vessels, which may be obliterated; some- 

 times passive congestion and small hemorrhages occur. Similar lesions were 

 described by Hamill ('12), Mott ('13), and other investigators cited by Raubit- 

 schek ('15) and Harris ('19). 



Vitamin Deficiencies. — The vitamin deficiencies in which the spinal cord has 

 been studied concern chiefly vitamin B (in beriberi) and vitamin C (in scurvy). 



Beriberi. — Rumpf and Luce ('00) reviewed the literature indicating that 

 previous investigators of human beriberi found no significant changes in the 

 spinal cord, aside from occasional atrophy of the anterior horn cells. Rumpf 

 and Luce found: "einen sparlichen Ausfall sowie eine unbedeutende Degenera- 

 tion der Vorderhornganglienzellen in alien Ruckenmarkssegmenten." Duerck 

 ('08) also made an extensive review of the subject (bibliography of 245 titles) 

 and described 11 original cases of human beriberi. The changes in the nervous 

 system, including the spinal cord, are variable in degree and not specific in 

 character, resembling the degenerations due to toxic causes. 



Experimental Beriberi. — In avian polyneuritis, Vedder and Clark ('12) by 

 Nissl's method found absence of the tigroid bodies in the cells of both ventral 

 and dorsal horns of the spinal cord (Figs. 63, 64). The stainable substance is 

 massed at one side of the cell and the nucleus sometimes stains poorly. The 

 mitochondria appear normal in these cells, however, even when the tigroid 

 bodies are markedly altered. Schnyder ('14), however, could find no appreci- 

 able change in the structure of the spinal cord in various animals (white mouse, 

 pigeon, chick, cat, dog) dying from beriberi. He used various histological 

 methods, including the Pal-Weigert. Findlay ('21) noted nearly complete 

 disappearance of the Nissl granules in avian beriberi (pigeons and fowls). 



