"Thucydides syndrome" reconsidered: new thoughts on the "Plague of Athens".

A recently published theory (N Engl J Med 1985;313:1027-30) argues that the famous Athenian epidemic of 430 B.C. was caused by a combination of influenza and toxin-producing staphylococci (the "Thucydides syndrome"). Although it is accepted by some medical authorities, and ostensibly supported by identification of modern cases, the theory's plausibility has not been carefully examined. The authors used an epidemiologic approach supplemented by historical and clinical observations to examine the likelihood that a "Thucydides syndrome" could have caused the Athenian epidemic. Arguing against the influenza theory are epidemiologic and clinical features of the disease, mathematical models of the spread of influenza, and empirical observations of epidemic influenza in premodern populations of known size and crowding. The authors conclude that neither influenza nor a "Thucydides syndrome" could have produced the Athenian epidemic. Epidemiologic features suggest either a zoonotic or vectorborne disease, a disease associated with an environmental source, or a respiratory infection with unusual alternative mechanisms of spread.

Differential effects of controllable and uncontrollable acute stress on lymphocyte proliferation and leukocyte percentages in humans.

This study examined the effects of a 30-min laboratory stressor on aspects of immune function in 24 men and whether behavioral control over the stressor moderates stress effects. The stressor consisted of mild (2.5 mA) electric shock and loud (100 dB) white noise administered in an unpredictable, intermittent fashion. During stress sessions, only half of the subjects were able to control the stressor. Subjects with control were yoked to subjects who could not control the stressor so that both groups were exposed to identical intensity and duration of noise and shock. Immunologic function was assessed across stress and nonstress conditions by measuring changes in lymphocyte proliferation to concanavalin A (Con A) and phytohemagglutinin (PHA) and by measuring changes in percentages of lymphocytes and their subpopulations, granulocytes, and monocytes. Results revealed that exposure to the uncontrollable stressor altered mood but did not affect immune function. In contrast, exposure to controllable stress did not alter mood but did result in lowered lymphocyte proliferation to Con A. Poststress percentages of monocytes were also lower in subjects exposed to the controllable stressor. Results suggest that acute stress can alter aspects of immune function in humans and underscore the importance of stressor controllability in moderating stress effects on human immunity.

Frequency of artifacts with xeroradiography using artifact-reduction techniques.

Artifact-reduction techniques applied to intraoral xeroradiography have reduced the overall artifact level by 56.4% and the single-image retake rate from 17.4% to 11.3%. Nevertheless, the frequency of xeroradiography artifacts is greater than for intraoral film radiography, whether using manual processing (1.8% retake rate) or automatic processing (3.4% retake rate). Methods to identify and prevent xeroradiographic image artifacts are discussed in detail.

Neuronal cholecystokinin and schizophrenia: pathogenic and therapeutic studies.

Neuroleptic-free schizophrenic patients received caerulein, a potent analogue of cholecystokinin octapeptide, in a fixed- and rising-dose schedule. In addition, neuroleptic-treated patients received a single dose of the peptide with a 4-week follow-up. No significant change in mental status was observed after any of these administration schedules. Peak plasma levels of caerulein were noted at 20-30 min after IM administration; at this time no changes in cortical evoked potential were demonstrated. Furthermore, levels of cholecystokinin were not found to be reduced, but were in fact elevated in lumbar cerebrospinal fluid of schizophrenic patients. These data argue against the antipsychotic efficacy of systemic caerulein administration and, because evidence of CNS response to CCK is lacking, suggest that other pharmacologic strategies may be necessary to effectively modify central peptide systems with systemically administered drugs.

Comparison of dental xeroradiography and conventional film techniques for the frequency and significance of image artifacts.

The frequency of occurrence and the classification of image artifacts were determined during a large-scale clinical dental radiographic study in which two conventional film techniques and xeroradiography were used. The resultant 1,220 radiographic images were evaluated for the presence of image artifacts. A list of commonly occurring artifacts was compiled, and frequency tables were constructed. Xeroradiography showed more image artifacts and also a higher retake rate due to artifacts (17.4% for individual images and 4.3% when images were evaluated as part of a complete-mouth survey). Many of the artifacts observed for xeroradiography were related to incomplete operator training and unfamiliarity with specialized imaging techniques.

The need for accuracy in historiography.

Historiographers must be especially accurate in their citations and references. An article by Wettersten contained numerous incorrect references and citations, and factual errors. Corrections are provided.