FIRST STEPS IN EMBRYOLOGY

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    only inseparable but are all transmissible to thesociety in which the individual affected-whether asvictim or aggressor-is transferred. This constellationof risks he describes as " degradation." Perpetratorsand victims of risks have at all times been removedfrom the community at large and placed in closed com-munities, the risks travelling with them. Institutionswhich have no proper facilities to prevent the spreadof the risks imported into them become slum institutions :and unfortunately this type of institution is quite commonthroughout the world.

    In a State service, where great numbers of administra-tors and employees have been given authority overgreater numbers of persons in public institutions, a groupcustodial relationship arises. Yet it is not clear whoare the persons responsible for the safe custody of peoplein public institutions. If, on occasion, the obligationof trust fails, the tendency is to name some official asresponsible, even though that official may have noexecutive powers. Dr. Robb contends that an anti-degradation philosophy must be accepted at the highestofficial levels before it can permeate to subordinatestaffs, because the physical means of guardianship areultimately controlled at the higher levels. An anti-degradation policy demands that institutions should beconstructed tofacilitate the work which must be carriedout in them. Architects in the past have designed anderected the most unmanageable of buildings, many ofwhich are still occupied. In such badly designed places,there may be provision for medical treatment and anabundance of kindness ; and yet custody may be farfrom safe. We share warmly his opinion that thearchitects and also the servicing departments shouldthoroughly understand the anti-degradation philosophy.

    Dr. Robb concludes that where the words " safecustody " appear in an enactment dealing with a publicinstitution, the interpretation of " safe " should mean" safe from the risks producing degradation." Hewarns that " strict custody " always tends to be danger-ous ; so all who are directly or indirectly responsible forthe custodial relationship are under an obligation tocooperate for safety. Public institutions might thenapproximate to that state which the law styles as" places of safe custody " irrespective of the specificpurpose of the institution.

    1. Odor, D. L., Blandau, R. J. Amer. J. Anat. 1951, 89, 292. Shettles, L. B. Amer. J. Obstet. Gynec. 1953, 66, 235.

    FIRST STEPS IN EMBRYOLOGYWE shall probably never be exactly certain of what

    takes place in the darkness of the human fallopian tubewhen the ovum is fertilised, but the last few yearshave seen a steady accumulation of indirect informationwhich enables us to make a reasonable guess. Circuxn-stantial evidence is here, as often in the law-court,almost as valuable as an eye-witness account. Thelatest weapon to be turned on this fundamental targetis the phase-contrast microscope. By its use, Odor andBlandau 1 studied the changes in living rat eggs removedfrom the fallopian tube, and the behaviour of spermatozoain relation to them. Now Shettles 2 has applied thistechnique to human ova removed at operation eitherfrom the ovarian follicle or from the tube, and he hastaken some remarkable photographs. The ova wereexposed to semen in vitro and incubated at 37C forvarying periods. Shettles finds that the corona andcumulus cells are rapidly stripped off a follicular ovumwhen small pieces of homologous tubal mucosa are addedto the preparation ; 5 this stripping is not effected byhyaluronidase or by semen alone. He failed to observeany evidence of a specific attraction of the ovum forthe spermatozoa, though those which come in contactwith it by chance become fixed to it. In vitro the ovumcan apparently be penetrated by several spermatozoa,

    though whether this occurs in vivo is uncertain. Italso appears that the whole spermatozoon may remainintact after penetration of the ooplasm, as has beenreported in several mammals.

    Such studies, carried on under artificial conditions,merely indicate probabilities, but they confirm thathuman as well as mammalian ova can be used to giveinformation about the process of conception. The earlierwork of Hamilton 3 in this country and Rock and hiscolleagues 4 5 in the U.S.A. is thus being extended, andphase-contrast microscopy has now proved its value ininvestigations of this kind.

    3. Hamilton, W. J. J. Anat., Lond. 1944, 78, 1 ; Ibid, 1946,80, 224.

    4. Rock, J., Hertig, A. H. Amer. J. Obstet. Gynec. 1948, 55, 6.5. Menkin, M. F., Rock, J. Ibid, p. 440.6. Payne, R. T. Brit. J. Surg. 1931, 19, 142; Lancet, 1933, i, 348;

    Proc. R. Soc. Med. 1938, 31, 398; Brit. med. J. 1940, i, 287.7. Bigler, J. A. Med. Clin. N. Amer. 1946, 30, 97.8. Jones, H. E. Arch. Dis. Childh. 1953, 28, 182.

    RECURRENT PAROTITIS IN CHILDHOOD

    THE pioneer work of Payne in the 30s added muchto our knowledge of recurrent parotitis ; but this disorder,which is by no means rare, continues to pass unrecog-nised. Published accounts of it are few ; the largestseries of cases in children was published in the UnitedStates by Bigler 7 a few years ago. Attention has againbeen drawn to it by Everley Jones, who describes 20cases in children observed over a period of five years inthe Midlands.

    Recurrent parotitis shows no decided age-distribution,though it is probably commoner in adults than inchildren. In children it seems to be equally commonin each sex, but among adults it is much commoner inwomen than in men. The principal clinical feature isswelling of one or both parotid glands, recurring one ormore times. The whole gland enlarges and is usuallytender ; and when recurrences are frequent some enlarge-ment may persist between exacerbations. The frequencyof recurrence may vary from weekly to yearly. In theactive phases there is always some discomfort, and usuallypain which may be severe. In most cases the orifice ofStensens duct usually looks normal, but in very acuteepisodes redness and swelling may be seen around it.Turbid saliva can nearly always be expressed, while insevere cases purulent saliva can occasionally be seen todrip from the duct orifice. In most cases the secretionproduces the " snowstorm " effect described by Payne;this is caused by small accretions of cells and mucus andcasts of ducts, suspended in turbid saliva. Calculi arenot formed. The diagnosis is confirmed by sialography.This valuable investigation, developed by Payne, revealscharacteristic changes which Everley Jones found in 13of the 14 children in whom it was done. When sialo-graphs are taken after injection through a blunt needleof 1-2 ml. of a radio-opaque fluid into Stensens duct,spherical dilatations of the finer ducts are displayed;occasionally dilatations, usually fusiform, are seen alsoin the main ducts. The dilatations are sometimes seg-mental. There may be no fever, and the white blood-cellcount is usually only slightly increased. Payne observedthat patients with recurrent parotitis are in generalconstitutionally nervous, and he suggested that instabilityof control of salivation via the cranial autonomic systemmight be a causal factor.As in other series, Everley Jones isolated