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F Putnam

Publications and source records attributed to F Putnam.

6 recordsLinked to original sources
PubMed1999

Using 'off the shelf', computer programs to mine additional insights from published data: diurnal variation in potency of ACTH stimulation of cortisol secretion revealed.

We describe the use of available computer programs to mine additional insights from published data. Graphs from four studies of ACTH and cortisol plasma levels collected throughout the 24 h day in humans were scanned into digital form and the data points extracted. To investigate the magnitude of ACTH stimulation of cortisol secretion across the 24 h, Monte Carlo methods were used to fit the parameters of a computer model of the ACTH-adrenal axis to the extracted data. ACTH was found to have a greater effect on cortisol secretion during the peaks of the cycle than at the nadir. This finding could not be explained by previously published dose response curves of ACTH effect. This implies that other modulators influence the effect of ACTH on the adrenal. This study also demonstrates how available computer programs can be used to examine models of physiologic regulation using data already available in the literature.

Adrenocorticotropic Hormone↗
PubMed1989

Dissociative states and epilepsy.

Since symptoms of chronic dissociative disorders such as multiple personality disorder (MPD) may be shared by patients with seizure disorders, we investigated the possible relationship between dissociative states and epilepsy. We monitored 6 MPD patients with intensive video-EEG recordings to determine whether epileptic phenomena have any correlation to the dissociative symptoms experienced by these patients. Previously, physicians had diagnosed epilepsy in all 6 patients; however, none proved to have epilepsy. In addition, we studied dissociative symptoms in 71 epileptic patients with the aid of a standardized questionnaire, the Dissociative Experiences Scale, and compared them with age-matched controls. While the group median score of cases with complex partial seizures was higher than that of normal controls, it was significantly lower than that of the psychiatric patients with MPD. Partial seizure patients with dominant hemisphere foci had higher depersonalization subscale scores than those with nondominant foci. Our data suggest that epilepsy is not a primary pathophysiologic mechanism for developing dissociative symptoms.

Adult↗
PubMed1987

Intravenous procaine as a probe of limbic system activity in psychiatric patients and normal controls.

Evidence from animal and human studies suggests that procaine hydrochloride may selectively activate limbic system structures and suppress neocortical structures. We administered a series of intravenous bolus doses of procaine hydrochloride to 31 subjects (7 with affective disorders, 17 with borderline personality disorder, and 7 healthy normal volunteers). Dose-related cognitive and sensory distortions and illusions were observed; affective experiences ranged widely from euphoric to dysphoric. Topographic electroencephalogram (EEG) analysis indicated selective increases in fast activity (26-45 Hz) over the temporal lobes; the degree of increase in this activity correlated with degree of dysphoria experienced. Procaine was associated with increases in secretion of cortisol, adrenocorticotrophic hormone (ACTH), and prolactin, but not with growth hormone. These preliminary data are consistent with the possibility that procaine might serve as a clinically useful probe of psychosensory, affective, electrophysiological, and endocrine effects referable to the limbic system.

Adrenocorticotropic Hormone↗
PubMed1986

Kindling enhances the stimulation of inositol phospholipid hydrolysis elicited by ibotenic acid in rat hippocampal slices.

The increment of inositol phospholipid hydrolysis elicited by ibotenic acid (IBO) is greater in hippocampal slices prepared from brain of rats receiving single or repeated hippocampal electrical stimulation or electrically induced amygdala kindling. In the latter group of rats, a potentiation of IBO stimulation of inositol phospholipid hydrolysis was associated with stage 3-4 of kindling according to Racine's scale. This increment returned to normal within one month after withdrawal from electrical stimulations. In both control and stimulated animals, 2-amino-4-phosphonobutyric acid antagonized the increment of inositol phospholipid metabolism elicited by IBO. The stimulation of inositol phospholipid hydrolysis elicited by carbamylcholine and norepinephrine was virtually unaffected by amygdala kindling.

Amygdala↗
PubMed1984

Electroconvulsive seizures inhibit amygdala kindling: implications for mechanisms of action in affective illness.

Amygdala kindling, the progressive development of seizures following repeated electrical stimulation, has been used as a model of epileptogenesis, neural memory, and the development of behavioral alterations. In an attempt to interfere with the kindling process, electroconvulsive seizures (ECS) were administered 6 h prior to or immediately after once-daily amygdala stimulation. ECS compared with sham ECS 6 h prior to kindling profoundly inhibited the development of amygdala-kindled seizures, while ECS immediately after the afterdischarge (AD) were not effective. In a second study, seven daily ECS, but not a single ECS followed by a 6-day delay, markedly suppressed established amygdala-kindled seizures compared with sham ECS controls. The generalized seizures of ECS thus appear to be paradoxically anticonvulsant to limbic seizures. Carbamazepine, a potent anticonvulsant for temporal lobe and limbic seizures in animals and man, inhibits amygdala-kindled seizures and is effective in the treatment of manic-depressive illness. The current findings suggest the possibility that the efficacy of ECS in affective illness may be, in part, related to its limbic antikindling and anticonvulsant effects.

Amygdala↗