Bias or artifact? A reply to Reade and Wertheimer

W. K. Reade and M. Wertheimer (see record 1977-08943-001) inferred in their analog study of the diagnosis of schizophrenia that diagnosticians' judgments were inappropriately biased by the information that a patient had an identical twin diagnosed as schizophrenic. The present authors argue that the procedures used in the study compelled the diagnostic behavior and that the implicit generalization from that study to reasonable clinical practice was unjustified. (1 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use of stable 48Ca in the clinical measurement of intestinal calcium absorption

Measurements of intestinal-calcium-absorption efficiency are fundamental for understanding calcium homeostasis in health and disease. Stable calcium isotopes are attractive tracers for such measurements, to avoid excessive radiation exposure to the subject and permit serial studies at short intervals. To realize this, we found it necessary to improve the sensitivity and precision of existing thermal neutron activation analyses for 48Ca. This report describes the details, sensitivity, precision, and accuracy of the improved method, and gives the results of studies in which intravenous 48Ca was used in conjunction with oral 47Ca to measure intestinal-calcium-absorption efficiency in patients.     

Effect of a high-beef diet on the fecal bacterial flora of humans

Ten human volunteers completed a 4-month diet series consisting of 1 month each of a control diet, a meatless diet, a high-beef diet, and the same control diet. Fat and fiber contents were essentially the same in all four diets, but protein content was doubled during the high-beef diet. During the 4th week on each diet, three stool specimens collected from each volunteer were analyzed for chemical composition and content of facultative, aerobic, and anaerobic bacteria. The bacteriological data are presented in this paper. High beef protein consumption had little effect on the composition of the intestinal flora. There were no significant differences in total counts of facultative and aerobic or anaerobic organisms in the feces when volunteers were on meatless or high-beef diets. At the species level, when counts during the two control diets were comparable, in only three instances did the change from the meatless to a high-beef diet significantly influence the bacterial numbers. The ratio of mean counts of anaerobic to facultative and aerobic organisms was approximately 15:1 during the meatless diet and 34:1 during the high-meat diet. The data indicate that animal protein consumption has little effect on the fecal bacterial profile in humans.     

Age-related variations in hepatic regeneration and erythropoietin production in the rat

Two hundred and thirty-five entrants into the MRC trial for mild to moderate hypertension were matched with control subjects in order to assess the psychological effects of a screening programme and recruitment into a clinical trial. The prevalence and incidence of psychiatric morbidity among the trial participants were compared with those of the controls by means of responses to a self-administered questionnaire and diagnostic psychiatric interviews. No differences among the groups were shown between screening and entry into the trial, but after entry the prevalence of psychiatric morbidity among the trial participants fell. This was due to a greater improvement of those with psychiatric symptoms at entry in this group, the incidence of new morbidity being similar among the groups.     

Behavioral effects of spinal cord transection in the developing rat

Albino rats, 0, 9, 12, 15, 18, 21 or greater than 90 days of age, were given a mid-thoracic spinal cord transection. Evaluation of responses of the hindlimbs to a variety of behavioral tasks was begun on the day of surgery and at intervals throughout the postoperative survival period (up to 300 days). Two investigators, independently and without knowledge of the animals' ages or survival times, rated the response data. Histological study showed all transections to be complete. Large differences in behavior are observed when animals trasected at the neonatal stage (0-4 days of age) are compared with animals transected at the weanling stage (21-26 days of age)37. Results of the present investigation indicate a critical period near 15 days of age; animals lesioned prior to this age (0, 9, 12 days of age) show response development and recovery similar to the neonatally lesioned animal, whereas those animals lesioned at a later age (18, 21, greater than 90 days of age) show little recovery and are behaviorally similar to the weanling transected animal. In animals lesioned prior to the fifteenth postnatal day, postural responses appear depressed for a brief period but recover rapidly while most responses of animals in the older groups are depressed for longer periods and never attain the degree of recovery characteristic of the neonatally transected animal. Finally, like the neonatally transected animal, rats lesioned on the ninth and twelfth postnatal day develop certain responses at appropriate times relative to normal response development. If, however, these responses are mature and supraspinal control is present at the time of lesioning, they appear to be permanently depressed and fail to recover.     

Continuous epidural analgesia in the obstetric patient: a feasibility study using a mechanical infusion pump

Eleven patients in uncomplicated labour received a continuous infusion of 0-125 or 0-25% bupivacaine solutions into the epidural space, using a simple rotary pump. Maternal and umbilical cord venous plasma bupivacaine levels were measured and were found to be within safe limits for mother and baby. Incidence of complications were noted.     

Chlorpropamide-induced thrombocytopenia

Thrombocytopenia is a rare complication of chlorpropamide therapy. An immunological mechanism is generally held responsible, but has never previously been proved. In the present case the existence of such a mechanism has been established.