pentosuria

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distributed from the Agency’s medical benevolenceaccount was R1002 10s., including contributions of£ 150 to the War Emergency Fund of the RoyalMedical Benevolent Fund, and JE100 to the BelgianDoctors’ and Pharmacists’ Relief Fund. At the sametime the insurers received an advantage by thereturn out of the commissions received by theAgency of certain sums which in 1918 totalled f:697.Since the foundation of the Agency £ 7200 have beenreturned in this way to insurers, a sum whichrepresents a direct saving to the profession.The Agency is not bound to any particularcompanies or forms of policy, and is ableto advise medical practitioners contemplatinginsurance as to the best form of policy to suit theirparticular conditions. The life insurance businessconducted through the Agency is considerable, andit is confidently anticipated that as the conditionsdisturbed by the war become more stable this formof business will largely increase. The insuranceof motor-cars is growing into an extensive branchof energy; in spite of the difficulties in the way ofmotorists created by the war and the shortage ofpetrol and of cars the number of motor insuranceshas increased, and experience has proved that theAgency, owing to the amount of business it conductsin this direction, is able to assure to its clients thattheir claims shall be promptly and generously met.In presenting the financial report the chairman,Dr. G. E. Haslip, was able to speak in the most ’,hopeful terms of the future of the Agency, andmentioned that vacancies, due to deaths of severalmembers of the committee, had been filled by the ’,election of Dr. E. Weaver Adams, Dr. H. A. DesVceux, Lieutenant-Colonel R. H. Elliot, I.M.S., Dr.R. A. Gibbons, and Dr. R. Langdon-Down. ’

PENTOSURIA.

THE occurrence of pentoses in the urine isnot so rare an event as is commonly supposed.Pentosuria is not necessarily associated with anymorbid symptoms, and does not of itself call for

any particular treatment; the importance of thecondition arises from the fact that its presencemay lead to a hasty diagnosis of diabetes, with con-sequent dietetic restrictions which are unnecessary.Two distinct types may be recognised : (1) the

alimentary form, in which the sugar is 1-arabinoseand the urine rotates polarised light to the right;(2) true or essential pentosuria, in which the sugaris usually i-arabinose and the urine is opticallyinactive, unless some other sugar is present as well.Alimentary pentosuria is apt to cause mistakesin diagnosis, especially at this time of the yearwhen fruit is being eaten more extensively thanat other seasons. The tolerance limit for pentosesis small, about half a gramme, and even in healthypeople a surfeit of cherries will cause the appear-ance of the sugar in the urine. Plums, goose-berries, strawberries, apples, and other fruits insufficient amount may give rise to a similar result.The amount of sugar excreted is usually small,0’5 per cent. or under, and as arabinose does notreduce as readily as dextrose the reaction isdelayed and is often of a peculiar type. When,for example, the urine is added to Fehling’s or

Benedict’s solution and boiled no change occursfor a time, but after continued boiling the colourof the solution suddenly changes to green, no

turbidity occurring even when the heating is pro-longed. A small percentage of dextrose or otherreducing substance may give a similar result.

More characteristic is the orcin reaction, bestcarried out in the form of Bial’s test. 4-5 c.cm.of Bial’s reagent (0’5 gr. orcin, 250 c.cm. fuminghydrochloric acid, sp. gr. 1’195, and 12 drops ofliq. ferri perchlor.) are heated to boiling in atest-tube and 1 c.cm. of the urine added ; on

standing a green-blue colour develops when apentose is present. If the solution is cooled,extracted with amyl alcohol, and the extractexamined with the spectroscope, it shows a bandbetween the red and yellow (C and D). Glycuronicacid may give a similar reaction, but it also givesTollen’s naphthol-resorcinol test. The most con-clusive evidence is furnished by preparing the di-phenylhydrazone with a melting-point of 216-218° C.for the 1-arabinose derivative and 204-205° C. for thei-arabinose compound, and the parabrom-phenyl-osazone which melts at 196-200° C. in the case of1-arabinose and 200-202° C. for the inactive form.As pentoses are not fermented by yeast the reducingpower of the urine in cases of pure pentosuria isnot impaired by mixing it with yeast and standingin a warm place for 24 hours.

PRACTICAL ISSUES ON THE ALCOHOLQUESTION.

WE welcome the scientific investigation of alcoholwith reference to practical issues. No one drinksa dilution of pure alcohol and water, and yethitherto, whilst interesting evidence has been

accumulated, physiological experiments have, inthe main, been based not on the actual beveragesconsumed by the public, but literally on C2H50H+ H2O. That formula does not by any meanspresent the story of such beverages as claret,sherry, port, beer, champagne, and so forth, none ofwhich is a mere dilution of pure alcohol, and it iswell known that these various alcoholic bever-

ages differ in their effects. The effervescentwine champagne, for example, has a differenteffect from claret, though both contain the sameamount of alcohol. There are important varyingfactors in the numerous alcoholic beverages con-sumed by the public which must count in regardto their effects. A mixture of whisky and water,for example, is below the specific gravity of water,whilst wines and beers are above this point onaccount of the solid matters in solution. Osmoticpressure must therefore vary, and with it the rateof diffusibility of the alcohol.In an important investigation undertaken for

the Medical Research Committee by Dr. EdwardMellanby,’ bearing on the absorption into, and dis-appearance from, the blood of alcohol under differentconditions, these points find interesting illustration.It is shown that differences in intensity of intoxi-cating symptoms obtained by taking the sameamount of alcohol in one or several drinks dependon the type of beverage drunk and the intervalbetween the drinks. Foodstuffs inhibit intoxica-tion in consequence of their action in delaying theabsorption of alcohol from the alimentary canal. Themost effective inhibitor is milk, the action of whichappears to be dependent to some extent on its fatcontent. Its specific influence in delaying absorp-tion more than counterbalances its general effectas a fluid, and Dr. Mellanby comments upon thestriking differences observed in the effects of a doseof alcohol when given two hours after the consump-

1 Special Report Series, No. 31. National Health Insurance, MedicalResearch Committee: Alcohol: Its Absorption into, and Disappear-ance from, the Blood under Different Conditions. London: Publishedby His Majesty’s Stationery Office.