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Biomedical subjects

R E Johnson

Publications and source records attributed to R E Johnson.

At least 181 records · Page 10Linked to original sources
PubMed1988

Correlates of adolescent drug use by gender and geographic location.

We examined the correlates of self-reported lifetime use of alcohol, marijuana, amphetamines, and cocaine within a sample of almost 7,000 high school sophomores in Arizona and Utah. Correlates of drug use (including parental attachment, religious attachment, educational attachment, conventional values, and drug-using friends) showed very similar patterns by gender, with some interesting differences by location. Drug-using friends are by far the best predictor of drug use for both males and females in Arizona and Utah.

Adolescent↗
PubMed1988

Cultural patterns and causal processes in adolescent drug use: the case of Greeks versus Americans.

Patterns of adolescent drug use in Greece (N = 174) and the United States (N = 2,610) are compared. The rates of self-reported lifetime alcohol and cigarette use are rather similar. For other drugs (marijuana, amphetamines, depressants, cocaine, LSD, PCP, and heroin) there is much more drug use in the United States. A causal model employing variables from social control and social learning theories is applied to drug use in both samples. We conclude that American theories of adolescent deviance assume certain cultural conditions, and therefore may need revision before they can be fruitfully applied to the behavior of young people in other cultures.

Adolescent↗
PubMed1988

Funding group benefit programs.

These authors examine various ways to fund group benefit plans. They devote special attention to self-funding of health care coverage.

Financial Management↗
PubMed1988

Buprenorphine: dose-related blockade of opioid challenge effects in opioid dependent humans.

This study assessed the blockade of hydromorphone challenge effects (cumulative s.c. doses of 0, 6 and 18 mg) during chronic buprenorphine treatment of opioid dependent subjects. Buprenorphine was administered daily via the sublingual route in ascending doses of 2, 4, 8 and 16 mg. Hydromorphone challenges were conducted after 10 to 14 days of chronic administration of each buprenorphine dose and 24 h after the last buprenorphrine dose. Buprenorphrine itself only produced dose-related effects in respiration rate. While subjects were maintained on 2 mg of buprenorphine, the hydromorphone challenge produced dose-related changes in physiological and self-report measures. As the dose of buprenorphine was increased, hydromorphone effects on self-report measures were attenuated to a greater extent than was noted for pupil diameter. The results of this study confirm previous reports of buprenorphine blockade of opioid agonist effects in humans and extent those findings by demonstrating both a buprenorphine dose-effect function and a dissociation between the potency of buprenorphine's opioid blockade for self-report vs. physiological measures.

Adult↗
PubMed1987

Chlamydia trachomatis infections in the United States. What are they costing us?

Chlamydia trachomatis has emerged as the most common sexually transmitted bacterial pathogen in the United States and is now recognized to cause substantial morbidity. To determine the economic consequences of chlamydial infections in the United States, we analyzed data from local, state, and national sources. We estimate that C trachomatis infections cost Americans over $1.4 billion per year in direct and indirect costs. Chlamydial infections in women account for 79% of this cost, although men and infants are also affected. Three fourths of the total cost is due to sequelae of untreated, uncomplicated infections. If the current rate of chlamydial infection persists, the projected annual costs will exceed $2.18 billion by 1990. Reducing the incidence of personal suffering and heavy economic burden imposed by C trachomatis infections requires establishment and maintenance of effective prevention/control programs.

Chlamydia Infections↗
PubMed1987

Human pharmacology and abuse potential of meptazinol.

Meptazinol was assessed in nine opioid abusers according to a double-blind, randomized, crossover design to determine if it produced typical morphine effects. A comparison of physiologic and subjective effects was made between morphine, 7.5, 15, and 30 mg, meptazinol, 70, 140, and 280 mg, and placebo. Both drugs constricted pupils. Meptazinol, 140 and 280 mg, decreased body temperature. Valid relative potency estimates of morphine to meptazinol were obtained for self-reported liking, opiate symptoms, and pupillary constriction. Meptazinol did not increase euphoria or sedation scale scores but did increase dysphoria scale scores. In the therapeutic dose range, meptazinol produced miosis, morphine-like identification and symptoms, limited liking, and some dysphoria. Dysphoria predominated at the 280 mg dose of meptazinol. From these data, it is concluded that meptazinol is not a typical morphine-like drug and has limited abuse potential.

Adult↗
PubMed1987

Job satisfaction of HMO pharmacy personnel.

This study identifies and examines the job satisfaction of pharmacy personnel in a large integrated prepaid group practice HMO. A large share of pharmacy personnel were satisfied with almost all aspects of their jobs. There were few differences between pharmacists and support personnel in satisfaction with specific aspects of their jobs. Among pharmacists, the challenge of their work, their management, and their physical working environment were the most significant factors in their overall job satisfaction while among support personnel the control of their work was the only significant factor. It seems that working in a large HMO can be satisfying for pharmacy personnel.

Health Maintenance Organizations↗
PubMed1987

Self-reported burnout among HMO pharmacists.

This study examines self-reported burnout, potential risk factors and causes, and self-reported solutions to burnout among different types of pharmacists in a large prepaid group practice HMO. A substantial share of pharmacists reported that burnout is or has been a problem with them. The quality of the job was mentioned as the most frequent cause of burnout by all types of pharmacists. More variety and responsibility and decreased workloads were the most frequently offered solutions to burnout by both staff and supervisor/specialist pharmacists. The findings suggest that pharmacists' burnout should be of concern to management.

Attitude of Health Personnel↗
PubMed1987

Relative afferent pupillary defect in a lesion of the pretectal afferent pupillary pathway.

A 23-year-old man presented with Parinaud's syndrome due to a mixed germ cell tumour of the pineal gland. Following treatment the syndrome resolved, but the patient was noted to have a relative afferent pupillary defect (RAPD) without any detectable visual dysfunction. The authors localize the lesion to the pretectal afferent pupillary pathway and discuss the differential diagnosis of an RAPD in the presence of normal visual function.

Adult↗
PubMed1987

Body composition in paraplegic male athletes.

The body composition and anthropometric characteristics of male paraplegic athletes (PARA, N = 22) were contrasted to an able-bodied ectomorphic (N = 22) and mesomorphic (N = 31) comparison group of moderately and highly trained male subjects. The validity of 12 body composition [density (Db)] prediction equations reported in the literature, 4 generalized, were determined (tested) on this special group of athletes (PARA). On the whole, the prediction equations over-predicted Db in PARA by 0.0039 to 0.0166 g X cm-3 (under-predicted relative fat by 1.8 to 7.4%). Five diameter, 11 circumference, and 7 skinfold measures were used in a SAS-STEPWISE multiple regression procedure with hydrostatically determined Db to develop several suitable Db prediction equations for the paraplegic athlete. Diameters were poor predictors (r = 0.60, SEE = 0.0164), while skinfolds, circumferences, or a combination of measures were acceptable, with the combined equation being best (r = 0.95, SEE = 0.0064). The findings of this study suggest that even generalized equations do not adequately predict Db in PARA and that paraplegic specific equations are presently best suited for predicting Db in paraplegic athletes. The results further indicate that although these equations meet many of the criteria of Lohman, the SEE and total error values are unusually high and make prediction of body composition using anthropometry in a heterogeneous group of PARA athletes slightly unreliable.

Adolescent↗
PubMed1987

Mother's versus father's role in causing delinquency.

This study examines parent-child relationships and self-reported delinquent behavior in a sample of over 700 adolescents. Family structure is controlled, and males and females are examined separately. Results indicate that males are more delinquent than females, that the gender of the adolescent is not related to the strength of parental attachment, that both males and females are closer to their mother than to their father, but that closeness to father is the better predictor of delinquent behavior--especially among the males. Finally, it is suggested that a revision of the conceptualization of parental attachment may make it a more useful variable in explaining delinquency.

Adolescent↗
PubMed1986

Effect of ethylene glycol and Ca2+ on the binding of Mg2+ x adenyl-5'-yl imidodiphosphate to rabbit skeletal myofibrils.

The binding of Mg2+ X adenyl-5'-yl imidodiphosphate (Mg2+ X AMP-PNP) to rabbit skeletal myofibrils has been measured in aqueous solution and in 50% ethylene glycol in the presence and absence of Ca2+. In water, the observed binding was weak with less than half the calculated myosin active sites filled even at 1 mM Mg2+ X AMP-PNP. In 50% ethylene glycol, the binding is at least 100-fold tighter and extrapolates to the expected number of binding sites. This is contrasted to the small change seen for Mg2+ X ADP binding between the same sets of conditions. This difference between Mg2+ X AMP-PNP and Mg2+ X ADP is attributed to the strong coupling of Mg2+ X AMP-PNP binding to dissociation of myosin cross-bridges. The Ca2+ sensitivity of Mg2+ X AMP-PNP binding in 50% ethylene glycol is taken as further evidence of the thermodynamic coupling of Mg2+ X AMP-PNP binding to cross-bridge dissociation. In addition, the binding of Mg2+ X AMP-PNP in 50% ethylene glycol is biphasic while Mg2+ X ADP binding under the same conditions is not. The biphasic Mg2+ X AMP-PNP binding could be caused by either the presence of two or more classes of cross-bridges or by negative cooperativity, but the presence of only a single class of Mg2+ X ADP-binding sites implies that if multiple classes of sites are involved, they do not simply differ in steric hindrance or accessibility of the binding site as a whole. The importance of using purified AMP-PNP in the study of actomyosin X AMP-PNP complexes is discussed.

Adenosine Triphosphate↗
PubMed1986

Acute effects of smoking marijuana on hormones, subjective effects and performance in male human subjects.

Four healthy male subjects smoked two marijuana cigarettes or one marijuana cigarette and one placebo cigarette, or two placebo cigarettes on separate days in a random order crossover design. Each marijuana cigarette contained 2.8% delta-9-tetrahydrocannabinol (THC). Plasma hormones and THC were measured before and after each smoking session. Plasma LH was significantly depressed and cortisol was significantly elevated after smoking marijuana. Nonsignificant depressions of prolactin, FSH, testosterone and free testosterone and elevation of GH also occurred. Concurrent measures of subjective effects via subscales of the Addiction Research Center Inventory, Single Dose Questionnaire and a Visual Analog Scale were generally elevated. Significant impairment on a psychomotor performance task paralleled elevations in subjective effects, hormone effects and peak THC determinations. Although all the hormone effects were within normal basal ranges, interactions between these systems, and their effects on behavior cannot be discounted.

Adrenocorticotropic Hormone↗
PubMed1986

The pharmacokinetics of pentazocine and tripelennamine.

The pharmacokinetics of single and combined doses of pentazocine HCl (40 and 80 mg) and tripelennamine HCl (50 and 100 mg) were studied in six healthy drug abusers. After intramuscular administration of 40 or 80 mg pentazocine alone, mean peak plasma concentrations at 15 minutes were 102 and 227 ng/ml, respectively, and mean plasma t1/2 values were 4.6 and 5.3 hours, respectively. After intramuscular administration of 50 or 100 mg tripelennamine, mean plasma concentrations at 30 minutes were 105 and 194 ng/ml, respectively, and mean plasma t1/2 values were 2.9 and 4.4 hours, respectively. After concurrent administration of pentazocine with tripelennamine, plasma pentazocine and tripelennamine concentrations at all time points were not significantly different from those when pentazocine or tripelennamine was administered alone. Coadministration of pentazocine and tripelennamine had no effect on the distribution, elimination, and clearance of either pentazocine or tripelennamine. In conclusion, there did not appear to be a clinically significant metabolic interaction between pentazocine and tripelennamine.

Adult↗
PubMed1986

Contact highs and urinary cannabinoid excretion after passive exposure to marijuana smoke.

Five healthy men were passively exposed under pre- and postplacebo controlled conditions to sidestream smoke from four and 16 standard marijuana cigarettes (2.8% delta-9-tetrahydrocannabinol [delta-9-THC]) for 1 hour each day for 6 consecutive days. Subjective effects produced by the 16-cigarette exposure conditions were similar to those observed after active smoking of one 2.8% delta-9-THC marijuana cigarette. Effects after the four-cigarette condition were less pronounced. Concurrent physiologic measurements showed no clear trends or effects of smoke exposure for either condition. Daily mean plasma levels of delta-9-THC ranged from 2.4 to 7.4 ng/ml with an individual high of 18.8 ng/ml for the 16-cigarette condition. With the use of EMIT cannabinoid assays with 20 ng/ml (EMIT 20) and 100 ng/ml (EMIT 100) cutoffs, urines positive per subject under the four- and 16-cigarette passive exposure conditions were 4.6 +/- 2.2 and 35.2 +/- 3.8, respectively, for the EMIT 20 and 0.0 and 1.0 +/- 0.8, respectively, for the EMIT 100 assay. From the results of these studies, caution is clearly indicated for individuals who might be substantially exposed to heavy marijuana cigarette smoke environments and for those interpreting marijuana screening data.

Adult↗