VAGINAL SMEARS—A Plea for More Critical Evaluation

To determine whether a conscious effort to reduce the incidence of equivocal (Class III) vaginal cytologic smear readings might have demonstrable clinical value, we have compared a previous study of our predictive efforts with a recent experience in screening a similar number of patients.It was possible to achieve an appreciable reduction in the incidence of Class III smears—from 2.4 per cent to 0.6 per cent. There was a modest increase in the reliability of the Class III smear as an indicator of cancer and a very notable increase in the reliability of the Class IV and V interpretations. While only 66 per cent of the earlier group with Class IV and V smears were shown to have cancer, 86 per cent of the present series with IV and V readings had malignant disease (97 per cent of the Class V group).The ultimate yield of malignancies was similar in the two series, but theoretically the overloading of Classes III, IV and V with women who do not actually have cancer necessarily leads to large numbers of diagnostic surgical procedures that might be avoided. Class III should be used to denote merely a temporary state of inconclusiveness rather than a real suspicion of cancer. With proper collaboration between physician and cytologist, most of the initially confusing situations can be either upgraded or downgraded to the proper rating, and eventually the bulk of patients standing to profit from conization will fall into Classes IV or V.     

SEROTONIN—Its Possible Relation to Allergic Disease

Increased amounts of serotonin as well as histamine have been found in the blood of animals during anaphylactic shock. Certain animals, particularly those in which antihistamines do not prevent anaphylaxis, have been found to have increased quantities of serotonin in the lung tissue during anaphylactic shock.Serotonin is a chemical derived from the amino acid tryptophan, which is widely distributed. It is excreted in the urine as the metabolite 5-hydroxyindoleacetic acid. Serotonin has been found in increased amounts in the blood of patients with carcinoids. The increase of serotonin in the blood and the finding of the excretory product in the urine has become a corroborative sign of the disease. The involvement of serotonin in the production of mental disease is evidenced by the effect of serotonin antagonists, which appear to influence mental behavior.That serotonin antagonists may be of ultimate value in the treatment of allergic disease is a possibility to be considered.     

Problems and paradigms: A mammalian molecular clock?

The molecular clock hypothesis remains controversial more than a quarter of a century after it was first proposed. A variety of approaches have been applied to testing the molecular clock in mammals. In many of these studies apparent refutation of the molecular clock has been based on false assumptions about the pattern of mammalian evolution. With a few exceptions there now appears to be little evidence for variation in the rate of molecular evolution among mammalian lineages, although comparison of more genes and proteins among a greater variety of mammalian orders is needed before a definitive conclusion can be reached on the issue.     

THE PAROTID GLAND—A Reinterpretation of Its Anatomic Structure

The parotid gland does not have a constant size and shape and relationship to the facial nerve. It consists of two glandular masses, one lying on the masseter muscle and the other in the pterygoid space to a varying depth. These two masses are connected by a glandular bridge, either wide or narrow, which lies on the posterior border of the mandible. The course of the facial nerve may be through this connecting bridge or it may pass to one side or a branch may pass on either side. In passing forward, the nerve branches may lie wholly within the glandular mass on the masseter, wholly beneath it or partly within it and partly beneath it.