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Biomedical subjects

D H Shaw

Publications and source records attributed to D H Shaw.

At least 55 records · Page 3Linked to original sources
PubMed1982

EEG sleep, depression, and aging.

To date little attention has been paid to the possible age-dependent relationships of EEG sleep measures in depression or to the implications of such relationships for diagnostic sensitivity and specificity. In a study of 108 patients with major depressive disorders (67 inpatients, 41 outpatients), age was shown to be a very powerful determinant of electroencephalographic (EEG) sleep patterns. Thus, among other sleep variables, sleep efficiency, delta sleep percent, and REM latency all showed significant linear declines with increasing age. Similar trends were seen in both inpatients and outpatients. Some variables were without age trends (age-stable), including sleep latency, REM sleep percent, and REM activity. These findings confirm those of an earlier report from our laboratory [45] and suggest that age-corrected sleep variables can be developed for clinical diagnostic application. Thus, using normative data from Gillin et al. [19] for comparison, a sensitivity level of 65% for age-corrected REM latency was demonstrated, together with a specificity of 95% and a diagnostic confidence of 92%. Data from a pilot study comparing EEG sleep measures in depression and dementia are also presented; these data suggest the potential utility of EEG sleep measures in the differential diagnosis of these two disorders, especially in patients with mixed symptoms. Additional areas for further research are reviewed with enumeration of specific testable hypotheses.

Adult↗
PubMed1981

Sleep and treatment prediction in endogenous depression.

The prediction of clinical response in depression has been based primarily on clinical symptoms and history. Recently, psychobiologic measures have been used to increase the accuracy of clinical prediction. In 34 drug-free patients with primary endogenous depression treated with amitriptyline, the application of EEG-monitored sleep criteria alone was more significant than clinical status alone in the prediction of clinical response. Prolonged REM latency and reduced difficulty in sleep onset following the administration of amitriptyline were the main sleep variables contributing to this prediction equation. These data suggest a strong relationship between clinical outcome and psychobiologic profile in patients with endogenous depression after a "pharmacologic probe" with a tricyclic antidepressant.

Adult↗
PubMed1981

Distribution of REM latency in depression.

While shortened REM latency is now considered the most consistent sleep feature observed among patients suffering from primary depressive episodes, and one which has generated a variety of hypotheses regarding possible mechanisms, few studies have employed long-term longitudinal designs. In the present investigation, REM latency was examined in 22 hospitalized depressed patients who were studied nightly during a 5-week protocol were bimodally distributed medication during that period; REM latencies were bimodally distributed with peaks occurring shortly after sleep onset and again 30-40 min later. Very short REM latencies (less than or equal to 20 min) were neither uncommon nor isolated events and persisted over time in this patient sample. These findings are discussed in relation to findings on shortened REM latency in other study populations.

Adult↗
PubMed1981

Neuropsychological assessment and EEG sleep in affective disorders.

The neuropsychological test performance of 76 hospitalized, depressed patients meeting RDC for the presence of affective disorder was assessed as part of a protocol involving amitryptyline (n = 53) or placebo (n = 23). Tests included the Trail-making Test (TMT), the Benton Visual Retention Test, and the Shipley-Hartford Scale. Clinical ratings and data concerning the characteristics of EEG sleep were also obtained. Analysis of data collected after a drug-free period of 2 weeks and again at the end of the protocol yielded the following conclusions. Base-line performance was inferior to norms for these tests, but for the TMT, scores were not as poor as that expected for brain-damaged patients. Poor performance was often associated with older age, the presence of psychotic features, and prolonged sleep latencies. Baseline Hamilton Rating Scale (HRS) was predicted best by TMT part B. However, this association was not as strong as that between HRS and poor sleep efficiency. Treatment with drug or placebo had little differential effect upon test performance over the course of the protocol. It is suggested that further research should utilize tests which have specificity in localizing cerebral lesions, so that any focal deficits in brain function in depression might be identified.

Adult↗
PubMed1980

Optional production and utilization of polysaccharide by Aeromonas hydrophila.

Glucans from the fish pathogen Aeromonas hydrophila have been extracted and purified by a method utilizing phenol/water followed by sodium deoxycholate rather than the traditional sodium hydroxide extraction. Presence of substantial amounts of these glucans was shown to be dependant on whether or not the substrate contained dextrose, a point which had import because of the low carbohydrate environment in which this species must survive and multiply. These glucans, produced in the log phase, were utilized during the growth period. The structures of the two purified glucans were examined by methylation analysis, periodate oxidation, and enzymatic degradation. The results indicated that A. hydrophila under low-carbohydrate growth conditions produced two similar but distinguishable alpha 1 leads to 4 linked glucans substituted alpha 1 leads to 6 by single monosaccharide residues or short chains to give an amylopectinglucogen type of polysaccharide.

Aeromonas↗
PubMed1980

RBC and plasma choline levels in control and depressed individuals: a critical evaluation.

Red blood cell (RBC) and plasma choline (Ch) were measured in 78 depressed, drug-free patients and in 23 normal, drug-free control subjects. RBC Ch levels displayed a huge variability among the patients, in contrast to those measured in normal controls. Plasma Ch levels, on the other hand, were more consistent within each group, and were correlated with age among the two populations studied. RBC Ch levels would appear to be independent of plasma Ch levels, and to be highly individualized and reproducible within each subject. A segment of the depressed population exhibited significantly higher RBC Ch levels than those seen in the normal control population. A clinical correlation of RBC and plasma Ch levels within the depressed population indicated that the patients with RBC Ch levels exceeding 35 nmole/ml might represent a diagnostically distinct subpopulation with specific clinical characteristics. Results presented here, although preliminary, suggest a role for RBC Ch as a biological marker in certain categories of depressive illness.

Adolescent↗
PubMed1980

Effects of aging on EEG sleep in depression.

Many of the same electroencephalographic sleep measures which differentiate between normals and depressed patients have also shown differences among age groups within a normal population. The present study examines sleep measures in 87 inpatients with a major depressive syndrome, examining the specific sleep variables which are correlated with age between 18 and 60 years. REM latency shows a distinct decline with age, an effect not well demonstrated in normals. Thus, REM latency may differ from variables which measure aspects of awakening and which show a clear age trend in normal subjects. Since many sleep measures are greatly skewed or have truncated distributions, the present paper provides several alternative styles of measurement which allow comparisons to be made easily and also facilitate multivariate testing.

Adolescent↗
PubMed1979

An automated analysis of REM sleep in primary depression.

The REM sleep of 23 nonpsychotic patients with primary depression was studied by means of an automated REM analyzer during a drug-free period and again during amitriptyline administration. Initial drug administration (50 mg) was associated with an immediate reduction in the number, average frequency, and average size of the rapid eye movements. The average REM size remained suppressed with continued drug administration while the average REM frequency showed a rebound which was responsible for a partial recovery of the number of REMs and total REM intensity to predrug levels. With regard to individual REM periods, REM frequency and REM intensity were redistributed during tricyclic administration so that the second REM period became more "intense" than the first REM period. This automated REM analysis technique provides an objective set of measures for characterizing discrete aspects of REM sleep during a depressive episode and for evaluating the changes in REM sleep during psychotropic trials.

Adult↗
PubMed1978

Electroencephalographic sleep recordings and depression in the elderly.

Eighteen patients over the age of 60 who were experiencing a major depressive episode were studied on a Clinical Research Unit after they had been drug-free for at least two weeks. All-night electroencephalographic (EEG) recordings revealed considerable fragmentation of sleep, a mean sleep efficiency of 58 percent, and very little delta sleep. The findings of reduced sleep time, shortened REM latency, and high REM density were similar to those in depressed patients under the age of 60. These preliminary findings support the application of EEG sleep recordings as a tool for the differential diagnosis of depression in the elderly.

Aged↗
PubMed1978

Lipopolysaccharides of the motile aeromonads; core oligosaccharide analysis as an aid to taxonomic classification.

Twelve motile Aeromonas strains have been examined with respect to the hexose and heptose monosaccharide residures present in the core region of their cell wall lipopolysaccharides. These strains were divided into three distinctly separate groups on the basis of the various combinations of hexose and heptose residues. The assignment of a strain to any one of the three groups furnishes a distribution which is substantially the same as that recently reported in a computerbased numerical analysis. All strains tested which were previoulsy named A. liquefaciens fall into the same group.

Aeromonas↗
PubMed1977

Disposition of 5-fluorouracil after intravenous bolus doses of a commercial formulation to cancer patients.

A high-pressure liquid chromatographic method that is used to determine the pharmacokinetic disposition of 5-fluorouracil from the plasma compartment is presented. The method requires only 0.5 ml of plasma for each determination and is sensitive to 0.1 mg of drug per liter. Novel methodology with the use of an ion-specific electrode technique for the determination of urinary excretion kinetics of 5-fluorouracil and its metabolites is also presented. This study demonstrated a much greater variability for the disposition of 5-fluorouracil by cancer patients than has been reported previously. The apparent volume of distribution for this drug varied more than 37-fold. Its plasma half-life varied more than 19-fold, and its urinary excretion half-life varied almost 400-fold. These data are compatible with the hypothesis that this variation could account, at least in part, for the variable therapeutic and toxic response to 5-fluorouracil. The methodology presented in this study is sufficiently simple and sensitive to allow assessment of this hypothesis by investigating cancer patients who receive therapeutic doses of 5-fluorouracil.

Aged↗
PubMed1976

Interactive effects of brain catecholamines and variations in sexual and non-sexual arousal on copulatory behavior of male rats.

In pargyline pretreated male rats, an intraventricular 6-hydroxydopamine procedure which resulted in subtotal brain catecholamine (CA) depletion produced a mild defict in copulatory behavior followed by rapid recovery. Challenges employed to study the behavioral capacities of these 'recovered' animals revealed: (1) a heightened sensitivity to acute treatment with the CA synthesis inhibitor alpha-methyl tyrosine (AMT) as reflected in a reinstatement and exaggeration of the original copulation deficit; (2) a greater dependence on the sexual eliciting properties of the female, since abolishing her soliciting behavior also reinstated and exaggerated the sexual dysfunction; and (3) a pattern of behavioral impairment indicating increased difficulty in both initiating sexual activity and maintaining copulatory performance. Furthermore, in males not copulating after 6-OHDA/AMT treatment, copulation could easily be induced by the simple application of a non-specific activating stimulus. On the basis of these data and parallel findings reported for other behaviors, we have concluded that: (1) both the initiation and maintenance of copulatory behavior in the male rat is the part dependent on normal functioning in one or more of the brain CA-containing systems; and (2) this copulatory deficit is symptomatic of a broader functional impairment reflecting reduced behavioral responsiveness to stimuli that normally elict appetitive or approach responses but not to stimuli requiring more automatic, inhibitory responses.

Animals↗