Page:Tropical Diseases.djvu/485

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XXVII]
ETIOLOGY
443

tion. A similar theory was propounded by De Giaxa in 1903. The latter ascribes the disease to a poison resulting from the action of Bacillus coli on sound maize after ingestion. He claims to have produced the anatomical lesions of pellagra in dogs by feeding them on porridge made with sound maize, and also to have obtained the same symptoms and lesions in animals inoculated with a toxin produced in vitro by the cultivation of Bacillus coli in maize media. These theories are disposed of by the harmlessness of maize in non-pellagrous districts.

(d) Toxic substances elaborated in decomposing maize.— Lombroso, in 1871, claimed that pellagra is due to the ingestion of certain toxic substances elaborated by saprophytes acting on the grain. In conjunction with others, he obtained from fermenting maize a watery extract containing a narcotic principle resembling conin, and" also an alcoholic extract and a red oil, both containing an alkaloid resembling strychnine, " pellagrozein." These two toxins combined, he holds, give rise to pellagra in the same way as sphacelinic acid and cornutin are believed to give rise to ergotism. In fowls inoculated with the toxins, Lombroso observed diarrhoea, loss of feathers, and death; in rats, wasting, choreiform movements, muscular spasm, and death; in men, vomiting, diarrhoea, desquamation of the epidermis, giddiness, dilatation of the pupil, and malnutrition.

These acute symptoms are in no way comparable to pellagra; identical results follow the administration or inoculation of analogous substances prepared by similar methods from wheat and other harmless foods.

Different investigators have extracted from damaged maize very different substances. Hausemann found a narcotic tetanic poison which he called "maizina." Selmi demonstrated the presence of ammoniacal acrolein. Pellogio extracted a bitter substance which produced paralytic symptoms. In 1881 Monselice analysed various specimens of damaged maize collected in pellagra districts, but was unable to find any alkaloid; he pertinently remarks that artificially fermented maize and the ordinary damaged maize are two very different things. In 1894 Pelizzi and Tirelli made experiments on dogs and rabbits, administering per os, or injecting subcutaneously or endovenously, the toxic substances obtained from cultures of the bacteria of maize. They observed spastic paresis of the posterior limbs and other symptoms which they considered characteristic of pellagra. Gosio, having observed that the commonest saprophyte of maize is Penicillium glaucum, prepared pure cultures of this fungus and extracted a substance belonging to the aromatic series. Ferrati made some experiments with a tincture of penicillium-damaged maize, and found that it is exceedingly toxic to rats, the animals dying in a few hours. Di Pietro noticed that only a certain variety of Penicillium glaucum has toxic properties. The poisonous substance is not present in cultures before the third day; it is a glucoside, and is found in the spores only. Experiments on guineapigs, dogs, cats, and rabbits produced symptoms very different from