Search PubMed⌕ Search

Biomedical subjects

D Pickar

Publications and source records attributed to D Pickar.

266 records · Page 15Linked to original sources
PubMed1979

A follow-up neurobiological study: why volunteer?

There is usually great concern over the use of psychiatric patients for clinical research, as it raises the ethical and legal issues of human dignity and autonomy. In this paper the authors describe and evaluate a follow-up neurobiological study of patients who had been discharged from a psychiatric research ward at least ten months earlier. It is pointed out that such studies are rare and that the writers were provided with the unique opportunity to examine attitudinal and motivational dimensions involved in the patients' agreement to participate in the study.

Affective Symptoms↗
PubMed1979

Tyramine infusions in bipolar illness: behavioral effects and longitudinal changes in pressor sensitivity.

Steady state intravenous tyramine dose pressor-response tests were administered to a patient with bipolar illness during depressed and hypomanic phases of her illness. The greatest tyramine sensitivity while unmedicated occurred when the patient was hypomanic, and the least sensitivity when she was depressed before her first switch. The data raise the possibility that changes in peripheral alpha-adrenergic receptor sensitivity accompany spontaneous mood cycles. Tyramine produced a replicable mood and cognitive alteration only in the infusion closest to the switch from hypomania to depression, suggesting that the CNS may be particularly susceptible to peripheral noradrenergic inputs at specific points in bipolar illness.

Adult↗
PubMed1978

Primary affective disorder, clinical state change, and MHPG excretion: a longitudinal study.

Urinary 3-methoxy-4-hydroxyphenethylene glycol (MHPG) excretion, which is thought to reflect CNS norepinephrine metabolism, has been shown to be significantly decreased in some depressed patients. Although there is consensus that urinary MHPG excretion varies directly with mood in rapidly cycling bipolar patients, there is little information on longer term state changes, such as those that accompany recovery from depression. Ten female patients with diagnoses of primary affective disorder were studied initially during an inpatient hospitalization and restudied at least ten months after discharge. Five healthy female comparison subjects were also studied over a similar interval of time. During the baseline period, the patient sample excreted less MHPG than did the comparison group. Improvement in clinical state from a seriously depressed baseline was associated with a significant increase in MHPG excretion, while the patients with recurrences of depression showed no change and continued to excrete less MHPG than the comparison subjects. These results suggest that urinary MHPG excretion may represent an index of psychobiological state in depressive patients.

Adult↗
PubMed1975

Are there two types of unipolar depression?

Personality traits and clinical characteristics in psychiatric outpatients with affective disorder were examined. Two groups of unipolar patients, divided on the basis of treatment response to tricyclic antidepressants, were compared to a bipolar group. While the unipolar-T (tricyclic responder) group showed premorbid personality traits of chronic anxiety and obsessiveness, neither the bipolar nor unipolar-L (tricyclic nonresponder, lithium carbonate responder) groups showed such findings. In fact, the unipolar-L and bipolar groups were similar not only with regard to personality variables, but also in terms of both drug response and certain family history features. These findings cast doubt on the homogeneity of unipolar depression and suggest the possibility of a subtype of unipolar depression with psychobiologic and personality features resembling bipolar disorder.

Adult↗
PubMedDate not supplied

Autonomic effects of clozapine in schizophrenia: comparison with placebo and fluphenazine.

Peripheral indicators of autonomic nervous system activity, including electrodermal activity and heart rate, were studied in 25 chronic schizophrenic patients given clinical trials of clozapine, a standard neuroleptic (fluphenazine), and placebo. The protocol included a rest period, presentation of nonsignal tones, and a reaction time task. Clozapine markedly attenuated electrodermal base levels and both phasic and tonic electrodermal responsivity compared to placebo, and somewhat less consistently compared to fluphenazine. Both electrodermal and vasoconstrictive orienting responses to tones were reduced. Elevated heart rate and reduced heart rate variability were also observed in patients taking clozapine. Many of these effects can be accounted for by clozapine's anticholinergic and antihistaminic properties. There was evidence that a smaller autonomic response to the mild stress of task performance and larger heart rate responses to nonsignal tones on the alternate treatments were predictive of a good clinical response to clozapine. These results suggest that when on alternate treatments good clozapine responders show more psychophysiological signs of pathology than clinical nonresponders.

Adult↗
PubMedDate not supplied

Pre- and post-dexamethasone plasma ACTH levels in depressed patients and normal controls.

Levels of plasma ACTH in relation to dexamethasone administration were evaluated in 16 medication-free patients with a major depressive episode and 39 normal controls. Depressed patients had significantly higher levels of plasma ACTH than controls both at 4:00 p.m. predexamethasone and 4:00 p.m. postdexamethasone. The significance of this finding is discussed.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Plasma cortisol and beta-endorphin immunoreactivity in human obesity.

The relationship of the endogenous opioid system and the hypothalamic-pituitary-adrenal axis to obesity was studied. Morning levels of plasma cortisol and beta-endorphin immunoreactivity in obese patients before diet treatment were found to be no different from those in matched family members of normal weight. In 32 untreated obese patients, no relationship between weight or body mass index (a measurement of obesity) and plasma levels of beta-endorphin immunoreactivity or cortisol was found. However, plasma cortisol levels were significantly correlated with obese patient ratings on the depression subscale of the General Health Questionnaire. Dexamethasone administration failed to suppress plasma beta-endorphin levels in untreated obese patients, but this finding has been reported in normal subjects in whom a similar assay methodology was used; it suppressed plasma cortisol levels in 29 of 32. The three patients resistant to suppression also suffered from benign essential hypertension. Plasma beta-endorphin immunoreactivity was unchanged, but cortisol levels significantly decreased as weight was lost on a 400-calorie/day modified protein fast. Patients who failed to complete the 6-month diet program had significantly increased plasma beta-endorphin levels compared to those who successfully completed the program.

Adult↗
PubMedDate not supplied

Naloxone reduces food intake in humans.

Hypotheses generated from animal studies that the endogenous opioid system is an important modulator of food intake suggest that blockade of the system in humans should affect eating behavior. To assess this hypothesis, seven normal volunteers were given 2 mg/kg naloxone or placebo on separate days in a double-blind, random but balanced cross-over experimental design. Compared to placebo, naloxone was found to reduce significantly total food intake from preselected prepared trays served 2.75 and 7.75 hours after drug administration (p less than 0.02). The reduction was considerable (28%), and although the magnitude varied greatly among individuals, reduction occurred in each. This reduced food intake was not accompanied by a demonstrable alteration of the volunteers' perceptions of their hunger. Further cautious experimental investigation of naloxone's effects during long-term administration and in patients with eating disorders is warranted in light of its apparent effect of reducing food intake in humans while not decreasing their satiety.

Adult↗
PubMedDate not supplied

Symptoms and EEG findings in the borderline syndrome.

Symptomatology and electroencephalographic abnormalities were examined in thirty-nine individuals with borderline personality disorder, compared with twenty unipolar depressed patients. Borderline individuals showed a much higher incidence of symptoms commonly seen in complex partial seizures or episodic dyscontrol, and in addition had a much higher incidence of EEG abnormalities, particularly posterior sharp activity. These findings suggest that neurophysiological dysfunction may contribute to the borderline syndrome.

Adolescent↗