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Human cerebrospinal fluid has been reported to contain a relatively small concentration of uric acid compared to that of plasma (cf. Table II). However, it is not known what proportion of these reported uric acid values is due to chromogenic substances similar to those giving the color reaction for uric acid in plasma (1). The introduction of enzymatic methods for determining uric acid specifically (2 to 5) has made reexamination of spinal fluid values advisable, particularly with regard to their relation to plasma ultrafiltrates. SUBJECTSCerebrospinal fluids 2 were obtained by lumbar puncture from individuals suspected of neurosyphilis and from others undergoing routine follow-up after antiluetic therapy. Those fluids which were serologically and Pandy negative were combined into 10-ml. pools, each pool representing 5 individuals. Total and urea-cyanide reagents. The concentration of uric acid equivalent to the color developed is termed total rate.2. Another (2-ml.) aliquot of the specimen is treated with uricase at pH 9.1 to destroy the uric acid present. It is then treated as above, the color developed being termed chromogen.3. The difference between the values for total urate and for chromogen represents the amount of uric acid destroyed by the specific enzyme and is therefore termed true rate.The actual size of the aliquots given in the preceding paragraph is that used in plasma determinations; cerebrospinal fluid contains so little urate that it is advisable to use twice or 3 times these amounts.The nature of the chromogenic substances in plasma and urine which give the color reaction for urate has been discussed recently (1) and will be reviewed more comprehensively in a forthcoming publication (6). A portion of the chromogen is non-purine in origin, but another portion is due to an incompletely characterized purine metabolite (or metabolites) of endogenous origin. In addition, methylurates from the methylxanthines of dietary origin contribute to the chromogen.The normal plasma urate values quoted are based upon repeated determinations on 31 normal individuals and are similar to the values obtained by Bulger and Johns (3) with a uricase method.Plasma for ultrafiltration was obtained from blood drawn in a heparinized syringe and immediately centrifuged; no attempt was made to preserve the normal carbon dioxide content. Ultrafiltrates of plasma were obtained by a modification of the method of Lavietes (7). The membranes used were DuPont No. 600 cellophane, soaked 3 days at 0°before used.8 RESULTSThe results of the urate partition in pooled normal cerebrospinal fluid are given in Table I, together with the average normal concentrations in plasma and the calculated C.S.F./plasma ratios. These data show that normal human cerebrospinal fluid appears to contain, on the average, only 6The cellophane membranes used in ultrafiltration were made available through the cooperation of E. I. du Pont de Nemours Co. 991

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PROBLEM AND METHODThis study investigates the possibility that the Verbal Scale of the WAIS(1) can be abbreviated to effect a considerable saving of time without sacrifice of either reliability or the variety of functions tap ed by the original instrument.The WAIE Verbal Scale records of 100 consecutive patients aged 16 to 72 at the Middletown State Hospital were taken from the files and rescored using selected items for each subtest according to the scheme in Table 1. Every third item waa used on the Information and Vocabulary subtests; only odd items were used on Comprehension, Arithmetic and Similarities. The Digit Span waa not abbreviated. For each subtest the total raw score waa then multi lied by the a propriate factor as indicated in $able 1 and &e results converted to weighted scores in traditional manner. Wechsler's tables were then utilized as usual in obtaining the abbreviated Verbal IQs. A preliminary application of the abbreviated scale showed that it tended to exaggerate IQs over 90. For this reason all IQs of 90 or over on the abbreviated scale were corrected by subtracting 2 points from the obtained Verbal

Three findings characterize the unusual purine metabolism of the Dalmatian dog (1): (a) Unlike other dogs, the urine of the pure bred Dalmatian contains large amounts of urate and relatively small amounts of allantoin, (b) per unit body weight, the urinary urate excretion of the Dalmatian is several times that of man, (c) although the Dalmatian excretes more urate than man per unit weight, this is accomplished at a plasma urate level much lower than that of man. In other words, the renal clearance of urate per unit weight per minute is much larger in the Dalmatian than in man.From the available literature, it is not clear whether the urate clearance of the Dalmatian exceeds the glomerular filtration rate or is merely equal to the glomerular filtration rate. Schaffer, Dill, and Stander (2) estimated urate and urea clearance simultaneously during a study of the renal effects of renin. In three clearance periods, when no renin had been given or after its immediate action had terminated, urate clearance was found to average 435 per cent of the urea clearance. These urate clearances were estimated with a colorimetric total urate method, but the same authors also studied enzymatically determined true urate values in other experiments on Dalmatians. If an average correction is made for the differences found between total urate and true urate values, the urate clearance in their experiments averaged 539 per cent of the urea clearance, a value far in excess of the glomerular filtration rate. Friedman and Byers, however, have presented data which they interpret as indicating an identity of urate clearance and glomerular filtration rate in the Dalmatian (3).