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B Myers

Publications and source records attributed to B Myers.

At least 55 records · Page 3Linked to original sources
PubMed1992

Pharmacological specificity of the increase in neurotensin concentrations after antipsychotic drug treatment.

Neurotensin is an endogenous neuropeptide that produces many CNS effects that are similar to the behavioral and physiological alterations seen after administration of antipsychotic drugs to laboratory animals. As previously reported, sub-chronic (3 week) and acute (single injection) treatment with haloperidol (1 mg/kg), a clinically effective antipsychotic drug increases neurotensin concentrations in the nucleus accumbens and the caudate nucleus. In contrast, a tricyclic antidepressant (desipramine, 10 mg/kg), an anxiolytic (chlordiazepoxide, 25 mg/kg) and a histamine H1 receptor antagonist (diphenhydramine, 20 mg/kg) did not alter neurotensin concentrations in these brain regions after sub-chronic or acute treatment. These data demonstrate pharmacologic specificity to the antipsychotic drug-induced increases in regional brain neurotensin concentrations, and support the hypothesis that these changes may contribute to the clinical efficacy of these drugs.

Animals↗
PubMed1992

Somatostatin in Alzheimer's disease and depression.

Somatostatin (somatotropin release-inhibiting factor, SRIF) was originally discovered (1) during the purification of growth hormone-releasing factor from rat hypothalamus and was subsequently isolated and characterized (2) in 1972 from ovine hypothalamus. Since its initial characterization, SRIF has been shown to fulfill criteria for a neurotransmitter and to directly modulate neuronal activity as well as acting as an inhibitory factor regulating endocrine and exocrine secretion. Alterations in cerebrospinal fluid (CSF) concentrations of SRIF have been reported in several diseases exhibiting prominent cognitive dysfunction, including Alzheimer's disease (AD), major depression, Huntington's chorea, multiple sclerosis, schizophrenia and Parkinson's disease, while evidence for regional brain tissue concentration deficits in SRIF are more specific for AD. This mini-review will focus on the studies reporting alterations in CSF and postmortem tissue concentrations of SRIF in AD and depression.

Alzheimer Disease↗
PubMed1992

Normal renal blood flow measurement using phase-contrast cine magnetic resonance imaging.

RATIONALE AND OBJECTIVES: This study assesses the ability of a cardiac-gated phase-contrast magnetic resonance imaging (MRI) technique to measure renal blood flow (RBF) noninvasively in humans. METHODS: In nine normal volunteers, total RBF in the renal arteries and in the left renal vein was estimated by MRI and correlated with RBF determined by the clearance of para-aminohippuric acid (CPAH) and the hematocrit level. RESULTS: Correlation of RBF estimated from left renal vein flow, with RBF by CPAH-hematocrit, yielded r = .86 (P less than .003). Repeated measurement of RBF by MRI demonstrated a high degree of reproducibility, with coefficients of variation ranging from 4.8% to 8.9%. However, the MRI measurements of arterial flow did not significantly correlate with the standard measurements. CONCLUSIONS: Reproducible noninvasive measurement of normal RBF is possible with the phase-contrast MRI technique used to measure renal venous blood flow.

Adult↗
PubMed1991

Bright light effects on body temperature, alertness, EEG and behavior.

The immediate psychophysiological and behavioral effects of photic stimulation on humans [bright light (BL) of 5K lux or dim light (DL) of 50 lux] were assessed in male subjects (N = 43) under four different conditions. For one condition the same subjects (N = 16) received alternating 90-min blocks of BL and DL during the nighttime h (2300-0800 h) under sustained wakefulness conditions. A second condition was similar to the first except that subjects (N = 8) received photic stimulation during the daytime hours. For the third and fourth conditions different subjects received either continuous BL (N = 10) or continuous DL (N = 9) during the nighttime hours. For the nighttime alternating condition body temperature decreased under DL but either increased or maintained under BL. For the continuous light condition, body temperature dropped sharply across the night under DL but dropped only slightly under BL. Sleepiness was considerably greater under DL than under BL, and the difference became larger as the night progressed. Similarly, alertness, measured by EEG beta activity, was greater under BL, and nighttime performance on behavioral tasks was also generally better. There were no differential effects between BL and DL on any measure during the daytime. These data indicate that light exerts a powerful, immediate effect on physiology and behavior in addition to its powerful influence on circadian organization.

Adolescent↗
PubMed1991

Replication of ocular isolates of human adenovirus is serotype-dependent in rabbit corneal organ culture.

The goal of the present in vitro study was to determine the ability of unadapted human adenoviral ocular isolates to replicate in the rabbit cornea. Rabbit corneas grown in organ culture (24 well plate) were inoculated topically with 50 microliters (5 x 10(5) pfu) of different ocular adenoviral serotypes (ATCC and clinical isolates). Control wells (no cornea present) were inoculated in a similar fashion. Viral replication was determined by serial aliquots titrated on A549 cells. We demonstrated sustained viral replication over time of all isolates (100%) of Ad1, 2, 5, 6, 8, 9, 11 and 37 tested. No isolates (0%) of Ad3, 7A, 19, and 4 demonstrated replication in our model. Peak titers varied among successful serotypes from 10(2) pfu/ml (Ad11) to 10(5) PFU/ml (Ad5), and among different isolates of a given serotype. We conclude that the ability of unadapted human Ad serotypes to replicate in rabbit corneas was serotype-dependent, and that subgroup C (Ad1, 2, 5, and 6) appeared to be the most successful subgroup.

Adenoviruses, Human↗
PubMed1988

Bacteriuria and bacteraemia in patients with long-term indwelling catheters--a domiciliary study.

Men with indwelling catheters and men and women with suprapubic catheters were studied in their homes. Urine and blood were cultured and body temperature recorded after every catheter change. Nearly all patients had infected urine after 4 weeks of catheterisation, and all had bacteriuria after longer periods, usually with a mixture of organisms. Culture on selective media revealed a wider range of organisms than was detected on routine C.L.E.D. and blood agar with antibiotic sensitivity disks, but routine culture gave adequate information for clinical purposes. Bacteraemia was demonstrated after 20 of 197 changes of urethral catheter and after one of 19 changes of suprapubic catheter; but no patient had pyrexia or other symptoms. However, two had rigors on other occasions. When assessing "risk factors" for blood-stream infection in catheterised patients, it is important to record the total incidence of bacteraemia, asymptomatic as well as symptomatic.

Bacteria↗
PubMed1988

Clinical utility of the MMPI in the evaluation of adolescent suicide attempters.

MMPI profiles of female adolescents hospitalized on a general pediatrics floor following a suicide attempt were compared to a control group of medically hospitalized, female adolescents referred for psychiatric evaluation. The suicide attempters had only a lower score on the K scale when compared to the control group. Results do not suggest that a single MMPI profile differentiates suicide attempters from a comparison group of adolescents with emotional difficulties. Implications of these findings are discussed.

Adolescent↗
PubMed1988

Ambivalence in cardiac transplantation candidates.

During three and a half years of psychiatric liaison with a cardiac transplantation program, the authors evaluated and followed 101 transplantation candidates. Ten exhibited pronounced ambivalence toward cardiac transplantation. Ambivalence appears to be associated with three factors: difficulties facing the seriousness of the cardiac illness, fear of the actual operation, and quality of life-concerns. An essentially nonpathological response, ambivalence can produce significant psychiatric symptoms and management problems in transplant candidates. Its resolution can be facilitated by psychotherapy, appropriate medication, peer support, and patience. Some patients may need particular assistance in understanding that refusal of transplantation is an acceptable alternative.

Adaptation, Psychological↗
PubMed1988

Informed consent issues in the cardiac transplantation evaluation.

As consultation-liaison psychiatrists to a cardiac transplantation team, we have observed various informed consent issues that are particularly associated with evaluation for cardiac transplantation. We discuss complicating factors that relate to each component of informed consent and present the defense mechanism of denial as a barrier to making the decision to accept or refuse transplantation. Changes in the evaluation protocol could preclude existing impediments to provision of information and patient autonomy; however, certain intrapsychic issues must be recognized as ongoing clinical realities to be addressed as the doctrine of informed consent continues to evolve.

Adult↗
PubMed1987

Metabolism and urinary excretion of 5-amino salicylic acid in healthy volunteers when given intravenously or released for absorption at different sites in the gastrointestinal tract.

In six healthy subjects serum concentrations of 5 amino salicylic acid (5ASA) and acetyl 5ASA were measured for up to 24 hours, and urinary excretion over 48 hours. After an intravenous injection of 3.26 mmol 5ASA serum concentrations fell rapidly with a distribution half-life of 17 +/- 2 min and an elimination half-life of 42 +/- 5 min. After 45 minutes acetyl 5ASA became the dominant compound and after seven hours serum concentrations of both components were almost unrecordable. Orally ingested 5ASA in three preparations to ensure its release in the stomach, small intestine and ileocaecal region respectively gave lower serum concentrations and urinary excretion than those obtained after an intravenous infusion. Bioavailabilities which ranged from 19% for ileocaecal release to 75% for release in the upper gastrointestinal tract, were calculated from areas under the serum concentration curves. Urinary excretion of 5ASA and its acetyl metabolite over 48 hours was 78%, 52%, 55%, and 21% respectively of the dose given intravenously and orally for gastric, small intestinal and ileocaecal release.

Adult↗
PubMed1986

Eosinophilia in Caucasians returning from the tropics.

A retrospective study was carried out on 119 Caucasians who were admitted to the Hospital for Tropical Diseases, London, for investigation of eosinophilia on return from the tropics. In 46 patients (38.7%) a definite parasitological diagnosis was made, and in all those followed up eosinophilia decreased with appropriate chemotherapy. In those patients where no cause for eosinophilia could be found, results suggest that empirical treatment with a broad spectrum anthelmintic agent may be justified in an attempt to produce a normal blood picture.

Adult↗