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Biomedical subjects

S M Southwick

Publications and source records attributed to S M Southwick.

At least 91 records · Page 5Linked to original sources
PubMed1991

Clinical features of cocaine-induced paranoia.

OBJECTIVE: The authors' objective was to assess the frequency and nature of cocaine-induced paranoia. METHOD: They interviewed 50 cocaine-dependent men consecutively admitted to a 28-day rehabilitation program. RESULTS: Thirty-four (68%) of the 50 men reported highly distressing transient paranoid states in the context of cocaine use. The men who experienced paranoia did not differ from those who did not in age, race, or measures of cocaine use. The mean duration and amount of cocaine use before development of paranoia of the men who reported paranoia were not significantly different from the mean lifetime duration and amount of cocaine used by the men who did not report paranoia. Paranoia became more severe and developed more rapidly with continued cocaine use. CONCLUSIONS: The transient paranoid state appears to be a common feature of cocaine dependence and does not seem to be simply a result of exceeding a threshold of use. Rather, affected individuals might possess a predisposition to this drug-induced state. The fact that paranoia became more severe and developed more rapidly with continued drug use is consistent with a sensitization model of cocaine-induced paranoia. In vulnerable individuals, limbic sensitization may underlie its expression, but localization to a specific brain region is speculative. Quantity of use and route of administration do not appear directly to predispose to this phenomenon. Future investigations must be aimed at uncovering the markers and meaning of vulnerability to transient paranoia in heavy cocaine users.

Adult↗
PubMed1991

Lymphocyte glucocorticoid receptor number in posttraumatic stress disorder.

OBJECTIVE: The authors' objective was to investigate the possibility that glucocorticoid receptor changes may be involved in the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis in posttraumatic stress disorder (PTSD). METHOD: They measured the number of lymphocyte cytosolic glucocorticoid receptors and plasma cortisol concentrations in 15 consecutively admitted male combat Vietnam veterans with PTSD and in a normal comparison group of 11 subjects. RESULTS: Both the patients and the normal comparison subjects showed a morning-to-afternoon decline in glucocorticoid receptor concentrations, paralleling the normal diurnal decline in cortisol levels. The number of glucocorticoid receptors was 63% greater in the morning and 26% greater in the afternoon in the patients with PTSD than in the normal subjects. No group differences in cortisol levels were observed, nor were glucocorticoid receptor number and cortisol levels correlated. The number of morning glucocorticoid receptors was positively correlated with symptoms of PTSD and anxiety. CONCLUSIONS: These results provide further evidence for a dysregulation of the HPA axis in PTSD. The finding that patients with PTSD had a substantially greater number of lymphocyte glucocorticoid receptors than normal comparison subjects is consistent with the authors' previous observations of low 24-hour urinary cortisol excretion in subjects with PTSD. Furthermore, the receptor changes observed are opposite of those reported in major depressive disorder. The present data, along with other findings of HPA abnormalities in PTSD, support the possibility of a greater negative feedback sensitivity at one or more levels of the HPA axis.

Adult↗
PubMed1990

Platelet alpha 2-adrenergic receptor binding sites in major depressive disorder and borderline personality disorder.

Platelet alpha 2-adrenergic receptor binding sites were measured in a group of patients with major depressive disorder (MDD) (n = 23) and in normal controls (n = 25). When all depressed subjects were compared to controls, there were no differences in either Kd (affinity of the ligand) or total binding site (number/platelet), although a significant change in the ratio of high to low affinity states was observed in the depressed group. When the depressed patients were subdivided into those with and without a co-occurring borderline personality disorder (BPD), the BPD group had significantly fewer alpha 2 high affinity binding sites, while the group with depression alone had significantly more binding sites (both low and high affinity) than the control group. The results support the concept that assessment of comorbid diagnoses may be essential to biological studies of depression.

Aged↗
PubMed1990

Low urinary cortisol excretion in patients with posttraumatic stress disorder.

In the present study, we replicated and extended our previous findings of low urinary free-cortisol levels in PTSD. Cortisol was measured in 16 male patients (nine inpatients, seven outpatients) with posttraumatic stress disorder (PTSD) and in 16 nonpsychiatric control subjects. The mean cortisol level in the PTSD group was significantly lower, and the range narrower, than that observed in control subjects. Low cortisol in PTSD did not seem to be related to the presence or absence of major depressive disorder or to overall psychiatric symptomatology as assessed by the sum Brief Psychiatric Rating Scale score. In the outpatient group, there was a relationship between PTSD symptomatology and cortisol levels. The findings suggests a physiological adaptation of the hypothalamic-pituitary-adrenal axis to chronic stress.

Adult↗
PubMed1990

Altered platelet alpha 2-adrenergic receptor binding sites in borderline personality disorder.

The authors found significantly fewer total platelet alpha 2-adrenergic receptor binding sites in 13 nonmedicated patients with borderline personality disorder than in 11 patients with borderline personality disorder who were receiving low doses of benzodiazepines and 18 nonpsychiatric control subjects. The two patient groups showed comparable degrees of depression as assessed by the Hamilton Rating Scale for Depression. However, nonmedicated borderline patients were considerably more anxious than medicated patients, raising the possibility that lower alpha 2-adrenergic receptor binding in borderline personality disorder is related to anxiety.

Anxiety Disorders↗
PubMed1990

Exploring the meanings of substance abuse: an important dimension of early work with borderline patients.

In this paper we encourage the evaluating clinician to approach substance abuse as though it were a symptom, like any other, that serves a psychological function for the borderline individual. During the assessment phase, this approach is likely to (1) generate interest among treaters (2) solidify rapport with the patient resulting in a positive attitude toward the assessing clinician with more informative self-reports, (3) elucidate, for the clinician, the patient's major deficits in personality structure, especially the inability to understand and control affective states, and (4) stimulate the patient's curiosity about the way in which emotions are perceived and processed.

Adult↗
PubMed1990

Noradrenergic function in panic disorder.

There is neuroanatomical, neurochemical, neurophysiologic, and behavioral preclinical evidence that suggests that the development of anxiety or fear relates, in part, to increased brain noradrenergic neuronal activity. In laboratory animals, uncontrollable stress has been shown to be associated with increases and altered regulation of brain noradrenergic function. Pharmacologic or electrical activation of noradrenergic neurons of the major brain noradrenergic nucleus, the locus ceruleus (LC), has anxiogenic effects in nonhuman primates. Elevated LC neuron firing is associated with anxiety or fear responses in freely moving cats. These observations are supported by clinical investigations that have demonstrated abnormal noradrenergic system regulation in panic disorder patients. From a neurodevelopmental perspective, these findings may be related to the natural course of panic disorder.

Animals↗
PubMed1989

Low platelet monoamine oxidase activity in borderline personality disorder.

Platelet monoamine oxidase (MAO) activity was significantly lower in nonpsychotic, nonorganic, unmedicated male inpatients with DSM-III-R borderline personality disorder (BPD) than in nonpsychiatric controls. Patients with BPD who also met DSM-III-R criteria for antisocial personality disorder had significantly lower MAO activity than those with BPD alone. Low MAO activity in this sample did not appear to be related to the comorbid presence of major depressive disorder or a history of substance abuse.

Adolescent↗
PubMed1988

Neuroendocrine aspects of suicidal behavior.

To assess biologic risk factors in suicidal behavior accurately, it is necessary to distinguish prospective from retrospective design. The former studies are more likely to elicit information concerning possible risk factors in suicide, whereas the latter may be better indicators of biologic traits. In both types of investigations, measures taken close to the suicide attempt are more likely to reflect the biologic state of the individual at the time of the behavior. Although the abnormalities present in suicidal individuals are not entirely clear, most evidence to date suggests an overactivity of the hypothalamic-pituitary-adrenal axis and a dysregulation of both serotonin and adrenergic metabolism. These systems are interrelated. Both animal and human studies have established that a multivariate biologic approach is necessary to the understanding of the pathophysiology of suicide.

Dexamethasone↗
PubMed1988

Neuroendocrine aspects of suicidal behavior.

To assess biologic risk factors in suicidal behavior accurately, it is necessary to distinguish prospective from retrospective designs. The former studies are more likely to elicit information concerning possible risk factors in suicide, whereas the latter may be better indicators of biologic traits. In both types of investigations, measures taken close to the suicide attempt are more likely to reflect the biologic state of the individual at the time of the behavior. Although the abnormalities present in suicidal individuals are not entirely clear, most evidence to date suggests an overactivity of the hypothalamic-pituitary-adrenal axis and a dysregulation of both serotonin and adrenergic metabolism. These systems are interrelated. Both animal and human studies have established that a multivariate biologic approach is necessary to the understanding of the pathophysiology of suicide.

Adrenal Cortex Hormones↗
PubMed1987

Sleep apnea and hypothyroidism presenting as depression in two patients.

Two patients are described who presented with depression and were later found to have both obstructive sleep apnea and hypothyroidism. Both patients had normal thyroxine (T4) levels but elevated thyroid-stimulating hormone (TSH) levels. Thyroid replacement led to resolution of both apnea and depression. The possibility of hypothyroidism as a cause of sleep apnea and depression is discussed.

Aged↗
PubMed1986

Characterization of water stress and low temperature effects on flower induction in citrus.

Experiments were conducted with containerized ;Tahiti' lime (Citrus latifolia Tan.) trees in order to define conditions needed to induce flowering. Cyclical or continuous water stress for 4 to 5 weeks induced flowering. Moderate (-2.25 megapascals, midday) or severe (-3.5 megapascals, midday) water stress as measured by leaf xylem pressure potential, for as little as 2 weeks induced flowering, but the response was more significant in severely stressed trees. Low temperature (18 degrees C day/10 degrees C night) induced a time dependent flowering response much like that of moderate water stress. Significantly negative leaf xylem pressure potentials as compared to controls were found only under water stress treatment, suggesting that a common stress-linked event, separate from low plant water potential is involved in floral induction. Leafless, immature cuttings from mature, field-grown trees were induced to flower by water stress treatment, suggesting that leaves are not essential for a flower inductive response.

Journal Article↗
PubMed1986

A rapid, simple synthesis and purification of abscisic Acid glucose ester.

A simple and rapid technique was developed to synthesize abscisic acid glucose ester. The free acid of abscisic acid (ABA) was combined with CsHCO(3) to form the Cs salt of ABA. The Cs salt of ABA was then combined with acetobromo-alpha-d-glucose tetraacetate, and the tetraacetate derivative of abscisic acid glucose ester was formed. Acetate groups were selectively removed from the glucose moiety with a crude enzyme preparation derived from Helianthus annuus seeds. Abscisic acid glucose ester was purified via silica gel column chromatography and identified by micro NMR.

Journal Article↗