758

to 49 years and decreases rapidly until 70. Accordinglythe mortality in women is 143% of the estimatedmortality, and in men 288%, or more than double thenormal. Bechgaard postulates a sex difference whichcauses the circulatory system to be more resistant toraised blood-pressure in women. The prognosis becomesworse with increasing age owing to associated myocardialdegeneration, and it is bad in malignant hypertension.Although Bechgaard’s material consists of patients

who had a blood-pressure of 160/100 mm. Hg, or a

systolic blood-pressure of 180 mm. Hg at the firstexamination, he defines the upper limits of normal

blood-pressure as 140/90 mm. " in agreement with mostof the recent investigations." Accordingly, he regardspeople who have a blood-pressure of more than 140/90mm. as hypertonics, even if they are over 40 years ofage. He adds, correctly, that " with this limit a verylarge number of older people (in case of the oldest morethan 50%) are regarded as hypertonics." This would notbe accepted by British and American observers, whoregard as abnormal in people over 50 a blood-pressureof 170/105 mm. Hg taken under proper precautionson at least three occasions. 8

DETERMINING THE TIME OF OVULATION

IN the investigation of cases of infertility it is often

important to ascertain the time of ovulation. Themethods used for this purpose include examination ofthe vaginal smear and the cervical mucous plug, biopsyof the endometrium, and, more recently, charting of thetemperature, which theoretically should show a slightfall at the time of ovulation.9 9 Unfortunately this lastmethod, which has the attraction of simplicity, does notseem to be proving as accurate as was hoped.Farris of Philadelphia, proposes another way of

establishing the time of ovulation. He finds that if the

patient’s urine is injected into an immature white rat,the rat’s ovaries become hypersemic if ovulation is takingplace, but not otherwise. The first morning specimenof urine is used, and 2 ml. is injected subcutaneously intoeach of two animals. The animals are coal-gassed aftertwo hours and the abdomens opened. The degree ofredness of the ovaries is compared with a standardcolour chart. Farris attributes the hyperaemia to theaction of pituitary gonadotrophin, which shows a peakrise at the time of ovulation.

This new test is certainly of scientific interest, andshould prove valuable in laboratories equipped to

perform it. The reading of the reaction, however, is

by no means easy, and Farris admits that abnormalreactions are fairly common. We still await the simple,cheap, . reliable, easily interpreted test for ovulationwhich gynaecologists would find so useful.

FUTURE OF PREVENTIVE INOCULATIONS

THE list of diseases for which satisfactory preventiveinoculations have been discovered is ever lengthening.Dr. H. J. Parish, in his presidential address to the

epidemiological section of the Royal Society of Medicineon May 23, reviewed current immunological proceduresfor each disease in turn. In the prophylaxis of diphtheriaand tetanus, typhoid and typhus, smallpox and rabies,yellow fever and cholera, the use of an appropriatevaccine or toxoid is universally practised. Evidence ofthe value of pertussis vaccine is still somewhat contra-dictory, and the short-lived immunity obtained frominfluenza vaccine at present limits its application.Promising preliminary reports are appearing on the useof an attenuated mumps virus, and an effective attenuated

8. Evans, W. Lecture to the Association of Industrial MedicalOfficers in London on June 19, 1946.

9. Barton, M., Wiesner, B. P. Lancet, 1945, ii, 663; Halbrecht, I.Ibid, p. 668 ; Nieburgs, H. E. Ibid, 1946, i, 627.

10. Farris, E. J. Amer. J. Obstet. Gynec. 1947, 52, 14.

measles virus may in time be produced. Dr. Parishbelieves that advances depend on close cooperationbetween the immunologist, the bacteriologist, and thechemist. Many unsolved problems remain to be tackled.Knowledge of the basis of racial and species immunity(inherent non-susceptibility) is entirely lacking. There isno explanation of the immunity of man to avian tuber-culosis or of dogs and goats to tetanus. Again, weknow that immunisation of the pregnant motherwith diphtheria prophylactic raises the circulating anti-body titre of the child, but although passive immunitycan be conferred on the mother by injection of diphtheriaantitoxin in horse serum, these immune bodies do not

pass the placental barrier. Most exotoxins can bemeasured quantitatively and qualitatively, and theyare relatively stable substances ; but endotoxins are ina different category and our present understanding oftheir action is much less complete. Dr. Parish suggestedthat in the near future much effort will be expended onelucidating the antigenic structure of organisms andpreparing pure stable antigens capable of exact measure-ment and less likely to produce allergic manifestations.Other paths of research are the use of new mineral saltsto combine with antigens-such as the aluminium-phosphate diphtheria toxoid of Holt-and carefulassessment of the antigenic potency of strains used inthe preparation of vaccines and toxoids. The work ofBarr and Glenny,l showing that higher antibody titrescan be obtained with two doses of A.P.T. at a three-monthly interval (instead of the usual one month)reminds one that we do not yet know the optimumspacing or dosage of diphtheria toxoid.

There is little hope, in Dr. Parish’s view, that artificialimmunity will be obtained without recourse to parenteralinjections, and the ideal of all antigens being adminis-tered in one single inoculation is far in the future. The

growing practice, however, of combining certain antigens(e.g., diphtheria and tetanus toxoids with pertussisvaccine) should, he thought, become more common,for it reduces the number of injections without apparentlyreducing the immunising value of each antigen.

OUT OF POCKET

ENGLISH local government has a fine record of unpaidservice. Those taking part have given generously oftheir leisure and energy, and in the past they have notgrudged the expenses that went with their duties, forthey were usually in a position to afford them. Today,however, with altered social and economic conditions

many of those best fitted to serve on local councils can

only do so at a sacrifice which we are beginning to feelit is unfair to ask them to undertake. The interdepart-mental committee which have just reported 2 to theMinistry of Health and the Scottish Home Department onthe expenses of members of local authorities confirmthese uneasy fears. From the evidence they receivedthey gained the impression that some members weresuffering undue hardship, and that suitable candidateswere being deterred from standing for election by fearof expense and loss of time. They have therefore recom-mended that local authorities should have power to payallowances to councillors who lose remunerative time inattending meetings and carrying out their public duties,and that councillors should be entitled to be paid travel-ling expenses and subsistence allowances. The principleinvolved is of importance to the new health service, whichwill depend so much on the wisdom and generosity ofthose who sit on its committees and boards. If we areto have practical members chosen from among workingpeople-whatever their work _may be—it is importantthat no-one should be hindered from accepting officefrom fear of out-of-pocket expenses.

1. Barr, M., Glenny, A. T. J. Hyg. Comb. 1945, 44, 135.2. Cmd. 7126. H.M. Stationery Office. Pp. 51. 1s.