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The effect of varying the time of sleep (2100-0500, 2400-0800, and 0300-1100 hrs) on the sleep, vigilance, and self-rated activation of 9 normal subjects was assessed. REM% increased, and Stage 2% decreased with progressively later bedtimes. An hour by hour analysis showed, however, that the increase in REM sleep was confined to the second 3 hrs of sleep. Vigilance and self-rated activation, assessed 30 min after waking, at midday and in the early evening, did not differ between conditions but varied reliably with time of day. It is concluded that shifts away from the conventional 2400-0800 sleep period do not impair performance. Rather, the changes in sleep (between conditions) and performance (within conditions) are, in the main, consistent with the known circadian rhythms of REM sleep propensity and performance efficiency. [ABSTRACT FROM AUTHOR]

Systematic variation in aspects of the sleep-wakefulness cycle of a depressed woman showed that recovery occurred reliably after 19 to 20 hours sustained wakefulness, unrelated to diurnal rhythm. Depression returned during as little as 15 minutes sleep. The effect of sleep deprivation was a specific response, probably unrelated to REM sleep. [ABSTRACT FROM AUTHOR]

This paper reports two experiments testing the hypotheses that the rate and degree of verbal conditioning are inversely related to the personality variables of rigidity and extraversion, these predictions being based on theoretical formulations by psychologists, R.B. Cattell and H.J. Eysenck, respectively. The most striking finding was that the conditioning procedures did not induce reliable, i.e. repeatable, changes in performance. This result which precluded an adequate test of the hypotheses under investigation is in marked contrast to previous studies using this and other methods of conditioning, and requires explanation.

The article presents information on a new stimulant called pemoline and a placebo that were used for the treatment of fatigue among students. Twenty-two university students conducted a study to assess the effect of the stimulant and the placebo. No significant difference was observed between the two treatments.

The article reports on psychometric test, the Eyesenck Personality Inventory (E.P.I.) with psychiatric patients. E.P.I. measures the personality dimensions of extraversion and neuroticism. The study found indicate that the neuroticism (N) and extraversion scales are stable, that N scores are influenced to a small, but significant degree by changes in the patient's clinical state, and that scores on its constituent Lie scale are significantly and inversely related to N scores. The data gathered from the study are samples taken from two psychiatric patients.

The article presents a double-blind trial concerning the efficacy of oxypertine as treatment for chronic anxiety neurosis. One group diagnosed with chronic anxiety neurosis were given 20 milligram of placebo, while the other group were given inert tablets of identical appearance. They are also administered with Eysenck Personality Inventory and IPAT Anxiety Scale. The researchers found no evidence that suggests the superiority of oxypertine against placebo in the treatment of the disease. Thus, they conclude that the IPAT Anxiety Scale is a not valid technique in the assessment of anxiety.

A letter to the editor is presented in response to an article on specificity of sleep deprivation in mental depression.

A letter to the editor is presented in response to an article about the Institute of Personality and Ability Testing Anxiety Scale in the October 1965 issue.

Objective: To evaluate the effects of nutrition counseling with or without oral supplementation in malnourished patients infected with the human immunodeficiency virus (HIV)., Design: Randomized controlled trial., Subjects: HIV-infected men (n=118) who were less than 90% of usual weight for height or who had lost more than 10% of body weight., Intervention: Nutrition counseling alone (control group) vs nutrition counseling plus enteral supplementation (supplement group) for 6 weeks. All patients were instructed to consume a diet that exceeded estimated total energy expenditure by 960 kcal/day., Main Outcome Measures: Weight, skinfold thickness, fat-free mass, grip strength, quality of life, and cognitive function (Buschke test)., Statistical Analyses: Differences in baseline variables and outcomes were evaluated using analysis of variance or the Wilcoxon rank sum test., Results: Ninety-nine men completed at least 4 weeks of treatment, 49 in the supplement group and 50 in the control group. Half the patients in each treatment group achieved at least 80% of their energy target. No differences in weight, skinfold thickness measurements, or quality of life were observed. Compared with the control group, the supplement group had larger increases in fat-free mass and grip strength, although the differences did not reach statistical significance., Applications: In the short term, nutrition counseling with or without oral supplementation can achieve a substantial increase in energy intake in about 50% of malnourished HIV-infected patients. Although further study is needed to evaluate long-term effects, these findings suggest that nutrition counseling has an important role in the management of malnourished HIV-infected patients.

To determine whether military personnel deployed outside the United States are at increased risk of Helicobacter pylori infection, 1,000 male U.S. Navy and Marine Corps personnel (mean age 22 years) were evaluated. Study subjects included 200 recruits, 500 shipboard personnel deployed for six months to South America, West Africa, and the Mediterranean, and 300 ground troops deployed for five months to Saudi Arabia. Among all 1,000 subjects, 247 (25%) were seropositive for H. pylori IgG antibody by an enzyme-linked immunosorbent assay; 24% of new recruits and 25% of troops who had been on active duty for a mean of four years. The prevalence of H. pylori antibody was higher among subjects who were older, nonwhite, foreign-born, and seropositive for antibody to hepatitis A virus. Among the 601 initially seronegative subjects evaluated before and after a 5-6 month deployment outside the United States, five seroconverted, for a rate of infection of 1.9% per person-year of exposure. As found in other populations in developed countries, these data indicate that among U.S. military personnel a large proportion of H. pylori infections occur before adulthood and infection is related to demographic factors. These preliminary findings also suggest that deployed U.S. military personnel may be at increased risk of H. pylori infection compared with adult populations in developed countries either from exposure in developing countries or from crowding.

Provision of nourishment to terminally ill patients has been a controversial topic in clinical medicine. Determination of the limits of palliative care requires an understanding of the disease process, as well as the boundaries of patient self-determination. With the advent of living wills, the determination of the patient to limit care, including nutrition support, has become socially acceptable. Difficulties arise when there are differences of opinion between the caregiver and the patient. The solutions to these conflicts are often decided in the courtroom, as demonstrated by the Cruzan and Quinlan cases. Living wills are often written to prevent unnecessary financial burdens in hopeless situations. As well, financial considerations influence the decisions made by caregivers in providing care to terminally ill patients. The following case report illustrates the conflict between patient self-determination and limitation of care for financial reasons. The use of substituted judgment within the Canadian health care system and the role of team meetings to resolve ethical decisions are discussed.

In this article we demonstrate that the difference in sleep between depressives and healthy controls varies systematically as a function of the mean age of the sample studied. The data were taken from 27 studies that had compared the sleep of drug-free depressed patients and age-matched healthy controls. In all, the studies give data for 822 patients (in 41 samples) and 621 healthy controls (in 37 samples). The mean age of the samples varied between 9 and 72 years. For total sleep time, minutes awake, sleep efficiency, minutes of slow-wave sleep, and REM latency, there are reliable age-related trends in both sets of samples. These trends follow a progressively diverging course such that, within studies, the mean difference and the standardized mean difference (d) between patients and controls increases as a linear function of the mean age of the former (i.e., the older the patients, the greater the difference). Possible reasons for the interaction are discussed.

Given the two-process model of sleep regulation, and the hypothesis that the sleep disorder in depressive illness is a consequence of a deficient Process S, it was predicted that relatively high levels of S would result in enhanced sleep continuity, increased slow-wave sleep (SWS), prolonged rapid-eye-movement (REM) latency, and less REM sleep. These predictions were tested in two studies. In Study 1, the level of Process S (at 0900 h prior to a 3-h sleep episode) was varied by altering the time and duration of prior nocturnal sleep (2400-0300 h, 0300-0600 h, 2400-0600 h). In Study 2, the leve of Process S (at 2400 h prior to an 8-h sleep episode) was varied by studying subjects when they had not napped or had taken 2-h naps beginning at either 1000 or 1900 h. As predicted by the model, SWS varied reliably depending on the level of S at bedrest, as did indices of sleep continuity at night. Contrary to prediction, however, REM sleep was either increased (Study 1) or did not change reliably (Study 2). It is suggested that, contrary to the other aspects of sleep, REM sleep is strongly influenced by circadian and homeostatic processes and that Process S plays a relatively minor role in its regulation.

Data from studies of naps and of shifted sleep were used to determine the relationship between two measures of rapid eye movement (REM) sleep (percentage of REM in the first 2 hr of sleep and REM latency) and prior wakefulness. For each sample, we calculated the difference between the observed value and that predicted by a cosine function that estimated the circadian rhythm of REM sleep propensity. The difference values were found to correlate reliably with hours and log hours of prior wakefulness. We conclude that while REM sleep is regulated in part by an endogenous circadian oscillator, it is also influenced by the duration of prior wakefulness.

The sleep of 4 groups (N = 8) of young healthy subjects was recorded during naps at either 09.00, 14.00, 19.00 or 24.00 h. For the first hour of sleep, conventionally scored slow wave sleep (SWS) and computed EEG power density (0-25 Hz) were found to increase exponentially as a function of prior wakefulness (range 3-18 h). The equations based on SWS and spectral analysis of the sleep EEG gave values for r' (the growth rate of the function) that were similar to each other (0.038 and 0.039, respectively) and to that reported by Daan et al. (1984; 0.055). These data are consistent with the proposal that process S, 1 of 2 processes believed to regulate sleep and wakefulness, increases exponentially during the waking day (Daan et al. 1984). In addition, they indicate that in this context SWS and spectral analysis provide measures of slow wave activity that are equally sensitive to changes in prior wakefulness.

Six drug-free depressed patients, each of whom acted as their own control, were studied for eleven consecutive days during which they were twice deprived of sleep for either 36 or 40 hours. The sequence of events was baseline (3 days), SD, recovery (3 days), SD, recovery (3 days). Blind ratings of clinical state were made on the basis of four-hourly interviews (standardized for each case), which were videotaped; sleep was monitored by conventional electrophysiological methods. Sleep deprivation had a beneficial, but transient, effect on four of the six patients studied. Changes in sleep were unrelated to changes in clinical state.

A phase advance of the circadian rhythm of rapid eye movement (REM) sleep propensity relative to the sleep-wake cycle has been hypothesized to account for the abnormalities of REM sleep in depression. One implication of this hypothesis is that an acute phase delay of sleep in normal subjects should produce the same abnormalities of REM sleep. A further implication is that changes in REM sleep that occur in normal subjects with delay shifts of sleep of progressively greater magnitude describe those that occur during the course of a depressive episode. This hypothesis was tested by computer simulation using two equations which, given the data derived from normal subjects experiencing phase delays of sleep, generated the REM latencies expected during successive stages of a depressive episode. For severely depressed patients, the computer-generated data matched those found empirically. The known correlation between severity of depression and REM latency, and the REM latencies of recovered patients, are consistent with the hypothesis.

Previous studies found an enhancing effect of glucose on fractional calcium absorption in humans but little information is available on the effect of different amounts of carbohydrate on Ca absorption. Thus, we studied the response of fractional Ca absorption to various loads of oral glucose coadministration with Ca in ten female subjects. After an overnight fast, 47Ca was administered orally on four occasions in solutions that contained varying doses of glucose (0 control, 56, 222, and 444 mmol). Seven of the ten subjects showed a positive response to glucose. In this group of responders there was a linear response to glucose between 0 and 222 mmol. No further increase was achieved at the higher dose of glucose. The response to 222 mmol glucose represented a 49% increase in Ca absorption compared with absorption without carbohydrate.

The effect of lactose vs glucose plus galactose on jejunal calcium absorption was studied in 10 subjects using a triple-lumen perfusion technique. In each, 30 cm of jejunum was perfused with two test solutions. The comparisons made were lactose (Lac) vs mannitol (Man), Lac vs glucose and galactose (GG), and Man vs GG. Compared with Man, Lac, and GG caused a significant increase in net water and sodium absorption and luminal calcium concentration. In subjects receiving both Lac and GG, water and sodium absorption were greater with GG. The only statistically significant increase in net calcium absorption occurred with Man vs GG in which water absorption increased from 16 to 350 mL.h-1.30 cm-1. However, by use of data from all test solutions, water and sodium absorption were found to be significantly correlated with calcium absorption (p less than 0.05). These results suggest that lactose or its component sugars enhance jejunal calcium absorption in proportion to their effect on fluid absorption.

Unlike sleep stages, which are assessed by standardized criteria, an informal survey by us showed that the definition of REM latency is relatively idiosyncratic. Differences in definition arise for two reasons: Differences in the definition of sleep onset, and the inclusion or exclusion of wakefulness that may occur prior to the first REM period. Seven definitions are identified. Each was applied to 70 records taken from 14 depressed patients, 5 remitted depressives, and 5 normal subjects. In all three samples, REM latencies calculated on the basis of the different definitions differed significantly. Reasons for adopting a common definition are discussed. It is suggested that, if established, the reliability and validity (concurrent and predictive) of the available measures would provide an empirical basis for selection.

The purpose of this study was to compare the absorption of calcium from two soluble Ca salts and determine if the oral Ca load test can be used as a simple measure of relative Ca bioavailability. Eight normal subjects ingested 750 mg Ca as solution of Ca(H2PO4)2 or Ca citrate (two occasions) tagged with 47Ca tracer. Absorption of Ca from the two salts was estimated from both the increase in forearm radioactivity and rise in urinary Ca (oral Ca load test). Both measures indicated that Ca was absorbed at least twice as well from Ca citrate as from Ca(H2PO4)2. However, the increment in urinary Ca 2-4 h after the oral load correlated with fractional absorption when only Ca citrate (r = 0.803, p less than 0.02) was ingested. For group comparisons the oral Ca load test is a rough index of Ca availability but cannot substitute for more direct measures of absorption in an individual.

A phase advance of some circadian rhythms (e.g., body temperature and rapid eye movement [REM] sleep propensity) relative to the sleep-wake cycle is thought to be implicated in the pathophysiology and pathogenesis of some affective disorders. Since this phase disturbance can be induced in normal subjects by acutely delaying their sleep onset, it follows that the outcome of this experimental procedure should resemble the symptoms of depressive illness. This hypothesis was tested by imposing a 6-hour phase delay of sleep in 10 young male subjects. There were reliable changes in observers' ratings of mood and in some self-report measures. For the most part, the effect was modest, being largely confined to variations within normal limits. Two of the subjects, however, were noticeably depressed when interviewed after either the first or the second night of phase shift.

By chance, we were able to record for five consecutive nights the sleep of a 61-year-old woman before each of two successive depressive episodes. In this patient, marked changes in EEG sleep (notably a decline in "sleep efficiency") preceded both episodes. These changes are considered to be of predictive, but not of etiological, significance.

A phase advance of the circadian rhythm of rapid eye movement (REM) sleep propensity relative to the sleep-wake cycle has been proposed to account for the abnormalities of REM sleep commonly found in depressed patients. One implication of this hypothesis is that a phase delay of sleep in normal subjects should produce the same abnormalities of REM sleep. The hypothesis was tested by computer simulation using equations based on data derived from normal subjects who had experienced phase shifts of their bedtime. At phase delays of between 4 and 6 hours (an estimate of the putative phase advance in depressed patients), the mean REM latency and the mean duration of the first REM period predicted by the equations did not differ significantly from those observed in depressed patients. The findings with respect to the distribution of REM latency were more equivocal.

Monoclonal antibodies (MAbs) of two different specificities were produced by immunizing mice with the semipurified M antigen of histoplasmin. One type, from clone CB4, was an immunoglobulin M that precipitated a polysaccharide present in histoplasmin and also formed immunoprecipitates with a cross-reactive polysaccharide present in extracts of Blastomyces dermatitidis and Coccidioides immitis. The second type of MAb, from clone EC2, was an immunoglobulin G that reacted in the enzyme-linked immunoelectrotransfer blot (EITB) assay with a doublet of proteins with an apparent molecular size of 70 to 75 kilodaltons. This molecule is proposed as the authentic M protein antigen that is recognized by M antibodies in sera from mice and rabbits immunized with Histoplasma capsulatum and from persons with histoplasmosis. The M factor also occurs in an abundant disulfide-bridged dimer which has a molecular size of 150 kilodaltons and is nonimmunoreactive under the conditions of sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Daan et al. (1984) have proposed that sleep and wakefulness are regulated, in part, by a "Process S" that increases during wakefulness and declines during sleep. Data derived from several studies were taken to determine the time course of Process S during both wakefulness and sleep. As required by the model, slow-wave-sleep (SWS; an index of Process S) was found to increase exponentially as a function of prior wake time (equation 1) and to decline exponentially as a function of time asleep (equation 2). The equations accounted for 91% and 96% of the variance, respectively. In addition, equation 1 accurately predicted the amount the amount of SWS in the first hour of nocturnal sleep.

We studied the effects of oral nutritional supplementation on respiratory muscle (RM) performance in 25 ambulatory patients with severe chronic obstructive pulmonary disease (COPD). There was a relationship between body weight and anthropometric parameters of nutritional status (triceps skinfold thickness [r = 0.67; p less than 0.005], midarm muscle circumference (r = 0.53; p less than 0.005), but body weight did not correlate with daily caloric intake, serum albumin, transferrin, or blood lymphocyte count. None of these measurements of nutritional status correlated with any measure of RM strength or endurance. In a randomized observer-blinded crossover trial, patients were allocated to one of two groups. In the first eight weeks of the study, group A received nutritional supplementation, and patients in group B were control subjects. In the second eight weeks, patients in group A were control subjects, and group B received supplement. Mean daily caloric intake and body weight increased in both groups while receiving supplement (both p less than 0.05). Calories provided by the supplement were frequently substituted for normal dietary calories. Any increases in RM performance in the group receiving supplement were matched by increases (due to learning) in controls. We conclude that oral dietary supplements have no important effects on RM performance in ambulatory patients with COPD.

The sleep of 10 bipolar patients was recorded for five consecutive nights following their recovery from a depressive episode. In all respects except the number of arousals, their sleep did not differ reliably from that of 10 sex and age-matched control subjects. We conclude that sleep measures are unlikely to be useful as trait markers of a depressive diathesis in bipolar disorder.