Southern Society for Clinical Research 407 (and by invitation) Philip Y. Paterson, M.D. and Elizabeth Smithwick, M.D. New Or- leans, La. (From the Division of Infec-

tious Disease, Department of Medicine, Tulane University School of Medicine.) Allergic encephalomyelitis has been produced

in dogs by immunization with homologous brain extracts mixed with adjuvants. The histo- pathology of the disease resembles that described by others in monkeys but a longer time is re- quired for the development of lesions and the incidence is lower. An antibody has been demon- strated in the serum of immunized dogs which reacts with an antigenic component of normal dog brain and peripheral nerve in complement fixation tests. The relationship between this antigen-antibody system and the experimental disease is not known; all dogs showing demye- lination have had antibody but others without lesions have also had antibody.

The antigen is demonstrable in aqueous and lipid-solvent extracts of brain. It is present in brain and nerve tissue from other species but not in other organs. It is not demonstrable in new- born dog brain tissue. It is resistant to boiling and to treatment with 10 per cent formalin. It is a component of the acetone-soluble, unsaponi- fiable fraction of white matter lipids and is separable from cholesterol. Specific immunologic activity may be demonstrated with less than 1 microgram of the partially purified material. Further studies bearing on the nature of this material will be presented. EFFECTS OF POSTURE AND OF COMPRESSION

(OF THE NECK ON GLOMERULAR FILTRA- :TION. William Viar, M.D. and Thomas Lombardo, M.D. (introduced by T. R. Harri- son, M.D.). Dallas, Tex. (From the De-

partment of Medicine, Southwestern

Medical College.) The rise in sodium excretion produced by the

recumbent position or by compression of the neck in the sitting position is not attended by significant change in glomerular filtration. Alter- ations in tubular activity must therefore be held responsible. RELATIONSHIP UF DURATION OF PHASES w

CARDIAC CYCI.E LENGTH AS DETERMINED IN HUMANS BY THE ELECTROKYMOGRAPH. kathryn Willis, M.D. (introduced by Tin&y R. Harrison, M.D.). Dallas, Tex. (From the Department of Internal Medicine,

Southwestern Medical College.) There is a paucity of data in the literature

SEPTEMBER, 1950

of the duration of phases of the cardiac cycle in human subjects. Therefore, it seems worth while to present the duration of these phases and relation to cycle length as determined in ,normal subjects by the electrokymograph. The average values are, namely, isometric contraction 0.039 second, rapid ejection 0.104 second, total sys- tole 0.26 second, protodiastole (time from relaxa- tion of ventricle to closure of semilunar valve) 0.039 second, as measured from tracings of ascending aorta in thirty-two normal subjects. Diastolic phases measured from left ventricular border tracings are the following: isometric relaxation 0.104 second, rapid filling 0.135 sec- ond and diastasis 0.16 second. Ranges OF these values are to be presented as well as comparison to total cardiac cycle length. TREATMENT OF INFECTIONS DUE TO PSEUDO-

MONAS ~~ERUCINOSA (BACILLUS PYOCY- ANEUS) WITH POLYMYXIN-REPORT OF A CASE OF MENINGITIS. Ellard M. Tow, M.D. and E. R. Hayes, M.D.) (introduced by James A. Greene, M.D.). Minneafiolis, Minn. (From the Department of Medicine, Baylor University College of Medicine,

Houston, Texas and Students’ Health Service, University of Minnesota.) Polymyxin is a polypeptide antibiotic which

acts as a bactericidal agent against Aerobacter aerogenes, Sal. typhosa, K. pneumoniae, H. in- fluenzae, and Pseudomonas aeruginosa but not against Proteus vulgaris. It is composed of five fractions having similar chemical and biologic properties but varying somewhat in toxic mani- festations. Because of evidences of nephrotoxicity and neurotoxicity occurring in some patients, as well as the overlapping antibacterial spectrum of other antibiotic agents, its general use has been limited. Infections due to Pseudomonas aeruginosa, however, frequently do not respond to other available antimicrobial agents. Clinical experience thus far has revealed a consistently favorable response in patients with Pseudomonas infections treated with polymyxin. Conse- quently, it is believed that because of the high mortality rate associated with systemic infections due to this organism, polymyxin represents the most successful means of treatment available at the present time.

A case of meningitis due to Pseudomonas aeruginosa occurring in a sixteen year old girl following spinal anesthesia, failing to respond to sulfonamide, penicillin and streptomycin therapy but responding to the intramuscular and intra- thecal administration of polymyxin, is discussed.