Biomedical subjects

P L Clopton

Publications and source records attributed to P L Clopton.

9 recordsLinked to original sources

PubMed1998

Risks associated with removal of ventricular epicardial pacing wires after cardiac surgery.

BACKGROUND: Epicardial pacing wires are routinely used for the diagnosis and treatment of bradyarrhythmias after cardiac surgery. The frequency of arrhythmias during removal of the wires is unknown, and methods of removal vary among institutions. OBJECTIVES: To describe the frequency of ventricular arrhythmias during removal of epicardial pacing wires from the right ventricle, to determine variables that are predictive of ventricular arrhythmias during wire removal, and to describe patients' perceptions of wire removal. METHODS: A convenience sample of 145 patients who had undergone cardiac surgery was studied during the course of 1 year. Electrocardiographic and vital signs were recorded throughout wire removal. Patients' records were reviewed for variables that could predict the occurrence of arrhythmias during wire removal: laboratory values, history of arrhythmias, medications, medical history, postoperative course, and pain reported by the patient. RESULTS: Sixty-six percent of patients had one premature ventricular contraction or more while the ventricular wires were being removed. Seven percent of patients had nonsustained ventricular tachycardia during wire removal. Patients who had repeat cardiac surgery had significantly more nonsustained ventricular tachycardia than did all other patients (P < .01). Only a history of heart failure (P < .02) was a significant predictor of premature ventricular contractions during wire removal. On a scale of 0 (no pain) to 10 (worst pain), the mean rating of pain intensity reported by patients was 2.39 (SD = 2.77). CONCLUSION: Patients may be at risk for ventricular arrhythmias during removal of epicardial pacing wires. Findings support the need for electrocardiographic monitoring while pacing wires are being removed.

Adult↗

PubMed1997

Intrapulmonary drug delivery of salmon calcitonin.

Calcitonin (CT) and other bone-active peptides have been restrained in clinical use by the need for parenteral administration. Although nasal and other transmucosal routes can be used for CT treatment, bioavailability and bioactivity of the peptide thus delivered are limited. We have evaluated the intrapulmonary route (IP) for the delivery of salmon calcitonin (SCT) in normal subjects. SCT was administered with a dry powder delivery inhaler. For comparison, each subject also received intramuscular (IM) SCT. Inhaled SCT produced significant hypocalcemia in all subjects as did injected SCT, and the peptide could be readily measured in serum by immunoassay. Compared by dose, IP SCT had 66% of the bioactivity and 28% of the bioavailability of IM SCT. This intrapulmonary route of administration should enhance the clinical acceptability of SCT and could also be applicable to other bone-active peptides.

Administration, Inhalation↗

PubMed1994

Neuroendocrine effects of light therapy in late luteal phase dysphoric disorder.

In 20 late luteal phase dysphoric disorder (LLPDD) and in 11 normal control (NC) subjects, circadian profiles of cortisol, prolactin, thyrotropin-stimulating hormone (TSH), and core body temperature were measured during midfollicular (MF) and late luteal (LL) menstrual cycle phases and after 1 week of light therapy either with (1) bright (tau 2500 lux) white morning (6:30 AM to 8:30 AM), (2) bright white evening (7 PM to 9 PM) or (3) dim (< 10 lux) red evening light, randomly administered in three separate luteal phases. In NC but not PMDD subjects, the cortisol peak significantly delayed in the LL compared with the MF phase. In PMDD, prolactin peak and amplitude were higher, prolactin acrophase earlier, and temperature amplitude higher during both the MF and LL phases. After light treatment, prolactin amplitude remained higher in LLPDD than in controls. In both groups, bright light shifted the cortisol acrophase, and AM light increased the prolactin nadir. Bright PM light increased the TSH nadir in LLPDD, but decreased it in controls. Thus, menstrual cycle phase, diagnosis, and light therapy may differentially affect neuroendocrine systems.

Arousal↗

PubMed1993

Bone density and body composition on the Pacific rim: a comparison between Japan-born and U.S.-born Japanese-American women.

Bone mineral density (BMD) of total body, spine, and proximal femur and the percentage of body fat in 151 U.S.-born Japanese-American women and 137 Japan-born immigrant Japanese-American women living in San Diego, California were measured using dual-energy x-ray absorptiometry. These data were compared with unpublished data from Japanese women obtained in previous studies in Hamamatsu, Japan. The age-adjusted BMD for the spinal level, femoral neck, Ward's triangle, trochanter, and total body, respectively, of U.S.-born Japanese-American women were 10.2, 9.8, 9.9, 9.2, and 2.7% higher than those of native Japanese women. The U.S.-born Japanese-American women had significantly higher body fat than immigrant Japanese-American women. Furthermore, the immigrant women had higher BMD and higher body fat than their native Japanese counterparts; however, no significant total-body BMD differences were found among the three groups after age, height, and weight were adjusted. The U.S.-born Japanese-American women had BMD values equivalent to those of white normals at the spine and femur. Significant life-style differences between U.S.-born and immigrant Japanese-American women were noted. Weight, exercise, early menarche, and years of lifetime estrogen exposure correlated positively with BMD. The significant negative correlates of BMD were age, smoking, and percentage of body fat. Our study presents data suggesting that immigration to the United States has produced a higher BMD in Japanese-American women that is attributable to changes in life-style and diet.

Absorptiometry, Photon↗

PubMed1982

Remote memory during marijuana intoxication.

The effects of acute marijuana intoxication on remote memory and new learning were assessed. To test for the effects of marijuana on remote memory, titles of one-season television shows, aired up to 14 years previously, were used in three tests measuring recognition, temporal judgement and detailed recall of facts from the shows. Marijuana did not affect remote memory in comparison to placebo. The effects of marijuana on the learning of a word list were also tested. Marijuana significantly impaired new learning at the same time that remote memory was unaffected.

Adult↗

PubMed1981

Adult psychiatric diagnosis and symptoms compatible with the hyperactive child syndrome: a retrospective study.

Characteristics of the hyperactive child syndrome have been described extensively. More recently, reports have indicated that manifestation of the hyperactive child syndrome may persist into adulthood, both as a continuation of childhood symptoms and as psychopathologic entities. This study evaluated 100 adult psychiatric inpatient Veterans for self-report of symptoms of childhood and adulthood hyperactivity, attentional deficit, and impulsivity. Psychotic and non-psychotic psychiatric patients reported a significantly higher incidence of childhood hyperactive syndrome symptoms than did age and sex matched controls. In both childhood and adulthood, character disorder patients reported the highest incidence of target symptoms.

Adult↗

PubMed1980

The effects of naloxone on methylphenidate-induced mood and behavioral changes: a negative study.

The effects of naloxone on IV methylphenidate-induced mood, behavior, and neurohumoral changes were assessed in eight psychiatric inpatients. While methylphenidate alone produced anticipated changes, the indications for significant naloxone-methylphenidate interactions were minimal. It is speculated that larger doses of naloxone might be required to produce modification of the psychostimulant effects.

Behavior↗

PubMed1979

Marijuana and the perception of affect.

The influence of marijuana on the ability to perceive emotions in others was studied in 30 male volunteers who were experienced marijuana users. Subjects smoked either placebo or active marijuana containing 6 mg delta 9-THC. The Affective Sensitivity Scale, a test developed to measure the ability to perceive emotions in others, was divided at midpoint and the two halves were administered before and after smoking, respectively. Analysis of variance demonstrated a decline in test scores following active marijuana administration, while changes following the placebo treatment were not significant.

Adult↗

PubMed1979

Interpersonal effects of marijuana. A model for the study of interpersonal psychopharmacology.

The effect of marijuana on affective changes and interpersonal skills, including empathy, acceptance, warmth, and genuineness, was studied in 20 dyadic relationships in which the experimental subject smoking marijuana containing 6 mg of delta-9-tetrahydrocannabinol and a placebo in separate trials. Marijuana caused a relative decrease in the ratings of the interpersonal skills of the experimental subjects and decreased affective resonance between the experimental subjects and their partners.

Adult↗