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Biomedical subjects

J Stevenson

Publications and source records attributed to J Stevenson.

At least 145 records · Page 8Linked to original sources

Cutaneous myiasis due to Tumbu fly.

A case of cutaneous myiasis due to larvae of the Tumbu fly Cordylobia anthropophaga is reported. The clinical presentation, treatment and prevention of this infestation is described.

Adult↗

An outcome study of psychotherapy for patients with borderline personality disorder.

OBJECTIVE: This study evaluated the effectiveness of well-defined outpatient psychotherapy for patients with borderline personality disorder. METHOD: Thirty patients with borderline personality disorder diagnosed according to the DSM-III criteria were given twice weekly outpatient psychotherapy for 12 months by trainee therapists who were closely supervised. The treatment approach was based on a psychology of self (this term being used in its broad sense), and strong efforts were made to ensure that all therapists adhered to the treatment model. Outcome measures included frequency of use of drugs (both prescribed and illegal), number of visits to medical professionals, number of episodes of violence and self-harm, time away from work, number of hospital admissions, time spent as an inpatient, score on a self-report index of symptoms, and number of DSM-III criteria (weighted for frequency, severity, and duration) fulfilled. RESULTS: The subjects showed statistically significant improvement from the initial assessment to the end of the year of follow-up on every measure. Moreover, 30% of the subjects no longer fulfilled the DSM-III criteria for borderline personality disorder. This improvement had persisted 1 year after the cessation of therapy. CONCLUSIONS: The results suggest that a specific form of psychotherapy is of benefit for patients with borderline personality disorder.

Adult↗

Clonidine treatment of Gilles de la Tourette's syndrome.

The safety and effectiveness of clonidine hydrochloride (3 to 5 micrograms/kg per day) were evaluated in 47 subjects with Gilles de la Tourette's syndrome, aged 7 to 48 years. Twenty-four subjects were randomly assigned to clonidine treatment and 23 to placebo. Forty subjects (21 given clonidine and 19 placebo) successfully completed the 12-week, double-blind clinical trial. Clinical ratings of tic severity improved for both groups. The magnitude of response was greater in the group receiving clonidine. Clinician-rated measures of motor tic severity, the degree to which the tics are "noticeable to others," motor tic counts from videotaped interviews, and parent-rated measures of impulsivity and hyperactivity were the most responsive to clonidine treatment. These results indicate that clonidine is more effective than placebo in reducing some of the tic and other behavioral symptoms associated with Gilles de la Tourette's syndrome.

Administration, Oral↗

Inhibition of prostaglandin synthesis fails to prevent gallbladder mucin hypersecretion in the cholesterol-fed prairie dog.

Gallstone formation in the cholesterol-fed prairie dog is preceded by an increase in mucin secretion by the gallbladder epithelium, and mucin hypersecretion is believed to promote cholesterol gallstone formation by accelerating the nucleation of cholesterol monohydrate crystals. Some studies have suggested that gallbladder mucin hypersecretion is mediated by increases in gallbladder prostaglandin synthesis, but other observations are difficult to reconcile with this view. An organ culture technique was used to measure mucin secretion in normal prairie dog gallbladder in response to exogenous prostaglandins and agents that increased or decreased endogenous prostaglandin production. Incubation with indomethacin produced a concentration-dependent inhibition of endogenous prostaglandin synthesis with virtually complete inhibition at 10(-5) mol/L indomethacin. However, indomethacin had no effect on gallbladder mucin secretion at concentrations as high as 10(-5) mol/L, and significant inhibition of mucin secretion was only found at 10(-4) mol/L indomethacin, a concentration that also produced a significant increase in lactate dehydrogenase release from cultured explants. Incubation of gallbladder explants with the calcium ionophore A23187 significantly stimulated endogenous prostaglandin synthesis in a concentration-dependent manner, increasing synthesis of prostaglandins E and F to as much as 278% +/- 20% and 335% +/- 21% of basal values, respectively; however, the same concentrations of A23187 did not stimulate mucin secretion. Incubation of gallbladder explants in the presence of exogenous prostaglandin E2 or prostaglandin F2a in concentrations as high as 10(-6) mol/L also did not stimulate mucin secretion. Prairie dogs fed a lithogenic 1.2% cholesterol diet showed a significant increase in gallbladder mucin secretion after 1 week (117.5 +/- 10.2% of control, P less than 0.05), and 4 of 5 had formed cholesterol monohydrate crystals after 3 weeks. Long-term treatment with indomethacin, 1.2 mg.kg-1.day-1, failed to inhibit gallbladder mucin hypersecretion (129.2 +/- 10.7% of control after 1 week) or cholesterol monohydrate crystal formation (3/5) in cholesterol-fed prairie dogs. Furthermore, incubation of explants with 10(-5) mol/L indomethacin failed to prevent in vitro mucin hypersecretion in cholesterol-fed animals. These findings suggest that prostaglandins do not regulate gallbladder mucin secretion in the prairie dog, and it is unlikely that increases in gallbladder prostaglandin synthesis are responsible for mediating gallbladder mucin hypersecretion during cholelithiasis in the prairie dog.

Animals↗

Acute bacterial thyroiditis presenting as otalgia.

A case of acute bacterial thyroiditis due to Haemophilus influenzae infection presenting as otalgia is reported. The features of this condition and the differential diagnosis from subacute (DeQuervains) thyroiditis are discussed.

Acute Disease↗

Ability of National Committee for Clinical Laboratory Standards-recommended quality control strains from the American Type Culture Collection to detect errors in disk diffusion susceptibility tests.

The National Committee for Clinical Laboratory Standards (NCCLS) recommends, as a quality control for the disk diffusion susceptibility test, the use of three strains from the American Type Culture Collection: Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922. This study assesses the capacity of these strains to detect errors in the overall method. ATCC strains were tested by comparing testing by the standard NCCLS-recommended procedure (ST) with testing under the following conditions: incubation at 25 degrees C, Mueller-Hinton agar depths of 2 mm (AD2) and 8 mm (AD8), agar pHs of 6.5 and 8, inocula with McFarland standards of 0.25 (0.25M) and 4.0 McFarland (4.0M), direct inoculation without preincubation of inoculum (DI), and a 2-h delay between inoculation and disk application (2HR). The frequency of zone measurements outside the NCCLS-recommended control zone limits were as follows: ST, 0%; AD2, 18%; AD8, 9.6%; pH 6.5, 7.9%; pH 8, 5.3%; 0.25M, 3.5%; 4.0M, 24%; DI, 3.4%; 2HR, 1.8%; 25 degrees C (only E. coli and P. aeruginosa were evaluable), 28%. These results suggest that the quality control strains are only partially effective in detecting single extreme laboratory errors and that careful laboratory supervision is necessary even in the setting of properly monitored quality control strains.

Clinical Laboratory Techniques↗

Concealed rectal opiates presenting as respiratory arrest: the importance of rectal examination in i.v. drug abusers.

A case of recurrent respiratory depression due to rectal absorption of concealed opiate drugs in an intravenous drug abuser held in police custody is described. The importance of rectal examination in intravenous drug abusers in police custody is stressed and it is emphasised that drugs may have been concealed in a body cavity at the time of arrest. The use of both the intramuscular and intravenous route for the administration of naloxone in treatment of unconscious intravenous drug abusers suspected of having overdosed on opiates is advocated as these patients frequently discharge themselves from hospital on regaining consciousness and may later present with recurrent respiratory depression.

Adult↗

Melatonin administration to blind people: phase advances and entrainment.

The purpose of this study was to test the phase-shifting and entraining effects of melatonin in human subjects. Five totally blind men were found in a previous study to have free-running endogenous melatonin rhythms. Their rhythms were remarkably stable, so that any deviation from the predicted phase was readily detectable. After determination of their free-running period and phase, they were given exogenous melatonin (5 mg) at bedtime (2200 hr) for 3 weeks, in a double-blind, placebo-controlled trial. The effects on the endogenous melatonin rhythm were assessed at intervals ranging from several days to 2 weeks. Exogenous administration of melatonin phase-advanced their endogenous melatonin rhythms. In three of the subjects, cortisol was shown to be phase-shifted in tandem with the melatonin rhythm. A sixth subject [one of the coauthors (JS)] was previously found to have free-running cortisol and temperature rhythms and was plagued by recurrent insomnia and daytime sleepiness. He had tried unsuccessfully to entrain his rhythms for over 10 years. After he took melatonin (7 mg at 2100 hr), his insomnia and sleepiness resolved. Determination of his endogenous melatonin rhythm after about a year of treatment demonstrated endogenous rhythms that appeared normally entrained. The treatment of blind people with free-running rhythms has many advantages for demonstrating chronobiological effects of hormones or drugs.

Adult↗

Psychosocial correlates of severe temper tantrums.

Temper tantrums are common and distressing, but little epidemiological information is available about them. Attempts to identify psychosocial correlates of tantrums have used small samples and have not controlled for multiple concurrent behavior problems. We analyzed interviews from 502 English mothers of 3-year-olds. Tantrums were considered present if mothers reported tantrums three or more times a day or lasting 15 minutes or longer. Behavior problems were assessed using the Behavior Screening Questionnaire. Tantrums were reported in 6.8% of children, of whom 52% had multiple behavior problems. Factors independently associated with tantrums included maternal depression and irritability, low education, and use of corporal punishment, manual social class, marital stress, child care provided exclusively by the mother, and poor child health. Tantrums were not associated (at p less than 0.01) with gender, maternal employment, low social support, or single parenthood. Severe tantrums may indicate the presence of multiple behavior problems and psychosocial stressors.

Child Behavior Disorders↗

The effect of lifting protocol on comparisons with isoinertial lifting performance.

The purpose of the study was threefold: (1) to determine if protocol constraints affected scores on a box-lifting task; (2) to identify any differences in impact of protocol changes on male and female scores; and (3) to determine if these protocol changes affected correlations between maximal box-lifting scores and maximal scores obtained on isoinertial lifting tests. Two hundred and sixty nine participants (143 males and 126 females) completed maximal isoinertial lifting tests to 1.50 m and 1.80 m using a constrained protocol on an Incremental Lifting Machine (ILM). Participants were divided into three samples for completion of a maximal box-lifting task, with each sample using one of the following task protocols: (1) set style; (2) free style; and (3) ergonomically redesigned. Statistical analyses using general linear models procedures revealed that changes in protocol constraints significantly affected scores on lifting tasks. Removal of protocol constraints resulted in greater percentage increases in task scores for females than for males. Furthermore, disparate patterns between genders in task-test correlations were observed. It was concluded that the ILM was unable to predict female lifting capabilities accurately using any of the three protocols.

Anthropometry↗

Effects of spaceflight on the spermatogonial population of rat seminiferous epithelium.

Testes from rats flown on Cosmos 1887 were compared with vivarium control and synchronous control samples. The mean weights of flight testes, normalized for weight per 100 g, were 6.4% less when compared with the vivarium controls. Counts of spermatogonia from tissue sections (seminiferous tubules in maturation stage 6) from five animals in each group revealed 4% fewer spermatogonia in flight testes compared with synchronous controls and 11% fewer spermatogonia in flight samples compared with vivarium controls.

Animals↗

Morphological and biochemical examination of Cosmos 1887 rat heart tissue: Part I--Ultrastructure.

Morphological changes were observed in the left ventricle of rat heart tissue from animals flown on the Cosmos 1887 biosatellite for 12.5 days. These tissues were compared to the synchronous and vivarium control hearts. While many normal myofibrils were observed, others exhibited ultrastructural alterations, i.e., damaged and irregular-shaped mitochondria and generalized myofibrillar edema. Analysis of variance (ANOVA) of the volume density data revealed a statistically significant increase in glycogen and a significant decrease in mitochondria compared to the synchronous and vivarium controls. Point counting indicated an increase in lipid and myeloid bodies and a decrease in microtubules, but these changes were not statistically significant. In addition, the flight animals exhibited some patchy loss of protofibrils (actin and myosin filaments) and some abnormal supercontracted myofibrils that were not seen in the controls. This study was undertaken to gain insight into the mechanistic aspects of cardiac changes in both animals and human beings as a consequence of space travel (1). Cardiac hypotrophy and fluid shifts have been observed after actual or simulated weightlessness and raise concerns about the functioning of the heart and circulatory system during and after travel in space (2-4).

Actins↗

Perinatal factors in the expression of Tourette's syndrome: an exploratory study.

The search for nongenetic factors that mediate the expression of a genetic vulnerability to Tourette's syndrome (TS) is an important undertaking that may provide valuable clues concerning the pathophysiology of this disorder as well as potential treatment approaches. In a direct interview study, the perinatal experiences of 31 TS patients were compiled in an effort to identify risk factors associated with tic severity. Severity of maternal life stress during pregnancy, gender of the child, and severe nausea and/or vomiting during the first trimester were found to be significantly associated with current tic severity. Future longitudinal studies of "at-risk" children are needed to confirm these findings. Set in the context of a known chromosomal site for the TS diathesis, such studies will permit the identification and quantification of risk and protective factors in the expression of TS and further develop TS as a model neuropsychiatric disorder for the study of gene-environment interactions.

Adolescent↗

The social environmental correlates of reading ability.

The influences of social and family characteristics on individual differences in reading and spelling ability and IQ were investigated for 550 twin children aged 13 yrs. Measures of family social circumstances, parental background, the emotional atmosphere at home and the family's reading behaviour were used as predictor variables in multiple regression analyses with reading, spelling and IQ as dependent variables. There were consistent relationships between many of these measures and the dependent variables. The findings are compared to a previous biometrical genetic analysis of the same data set. It is concluded that the results are within the limits predicted by the genetic analysis. Most of the effect of these environmental influences on children are general, i.e. related to IQ, and not specifically related to reading. After controlling for the effects of IQ on reading, only family size and some aspects of parent-child relationships were significant predictors of reading ability.

Adolescent↗