PubMed Health⌕ Search

Biomedical subjects

A G Blouin

Publications and source records attributed to A G Blouin.

14 recordsLinked to original sources

Courtship songs of Drosophila pseudoobscura and D. persimilis. II. Genetics of species differences.

Although male courtship songs have been repeatedly implicated in sexual isolation between numerous Drosophila species, no genetic studies have evaluated the genetic basis of differences between species beyond using quantitative genetic analyses of hybrids or surveying associations of song characters to five or fewer genetic markers. Here, we dissect the genetic basis of the difference between D. pseudoobscura and D. persimilis in two courtship song elements (interpulse interval and intrapulse frequency) using 15 molecular markers. We also evaluate the association between song elements and sexual isolation in these backcross hybrid males of these species. We find that song differences between these species are associated with at least two or three genomic regions, and the species difference in interpulse interval may be oligogenic. Courtship song differences are especially strongly associated with two inversions that differentiate these species. Further, we found that interpulse interval is strongly associated with mating success to D. pseudoobscura females, while intrapulse frequency is associated with mating success to D. persimilis females. Implications of these findings are discussed.

Animals↗

Light therapy in bulimia nervosa: a double-blind, placebo-controlled study.

The effects of light therapy on food intake and affective symptoms of bulimia nervosa (BN) were examined in a double-blind study. Eighteen women who met DSM-III-R criteria for BN were randomly assigned to receive either 2500 lux of bright light (experimental condition) or < 500 lux of dim light (placebo condition) daily in the early evening for a 1-week period. The Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorder Version (SIGH-SAD), the Beck Depression Inventory (BDI), and the Bulimic Symptoms Checklist were administered to subjects before light exposure, after 1 week of light exposure, and after 7 days of withdrawal of light exposure. Throughout the study, the Profile of Mood States and the Daily Binge Record were completed daily. Compared with subjects in the dim light condition, subjects in the bright light condition showed a significant improvement in depressed mood during light exposure, as measured by both the BDI and the SIGH-SAD. There was a return to pretreatment levels of depression after withdrawal of light exposure. No changes in depression were noted in the placebo group. No effect of light therapy was found on the frequency, size, or content of binge-eating episodes. The results are discussed in terms of the physiological processes associated with light therapy and seasonal affective disorder that may underlie the affective and food intake symptoms of BN.

Adult↗

Body image and steroid use in male bodybuilders.

This study was designed to examine the association between body image and eating-related attitudes among male bodybuilders in relation to two athletic comparison groups, runners and martial artists. It was also of interest to examine whether steroid use may be associated with body image disturbances in athletes. The volunteer sample of 139 male athletes recruited from fitness centers comprised 43 bodybuilders, 48 runners, and 48 martial artists (tae kwon do practitioners). Standardized measures of body dissatisfaction, drive for thinness, drive for bulk, bulimia, self-esteem, depression, maturity fears, and perfectionism as well as questionnaires designed to measure attitudes toward steroids, and rates of steroid use were administered in a manner that encouraged disclosure. Bodybuilders reported significantly greater body dissatisfaction, with a high drive for bulk, high drive for thinness, and increased bulimic tendencies than either of the other athletic groups. In addition bodybuilders reported significant elevations on measures of perfectionism, ineffectiveness, and lower self-esteem. They also reported the greatest use of anabolic steroids and most liberal attitudes towards using steroids. Steroid users reported that the most significant reason for using steroids was to improve looks. Steroid users reported an elevated drive to put on muscle mass in the form of bulk, greater maturity fears, and enhanced bulimic tendencies than nonusers. The results suggest that male bodybuilders are at risk for body image disturbance and the associated psychological characteristics that have been commonly reported among eating disorder patients. These psychological characteristics also appear to predict steroid use in this group of males.

Adolescent↗

Prognostic indicators in bulimia nervosa treated with cognitive-behavioral group therapy.

Prognostic indicators of short-term outcome were identified in 69 women with the DSM-III-R diagnosis of bulimia nervosa who participated in a weekly 10-session structured cognitive-behavioral outpatient group program. Prior to treatment, all subjects completed the computerized Diagnostic Interview Schedule (DIS), the Moos Family Environment Scale (FES), the Diagnostic Survey for Eating Disorders (DSED), the Beck Depression Inventory (BDI), the Hopkins Symptom Checklist, Revised (SCL-90-R), the Bulimic Cognitive Distortions Scale (BCDS), the Eating Disorders Inventory (EDI), and the Bulimic Symptoms Checklist (BSCL). The latter three scales were readministered on completion of the 10-week group. Symptom improvement was assessed by examining percentage reduction in binge frequency, purge frequency, and summed scores for the EDI subscales Bulimia, Drive for Thinness, and Body Dissatisfaction. The only significant predictor of improvement in binge frequency and bulimic cognitions was family environment. Conflicted, controlling, and over-organized family environments appear to impede both reductions in binge frequency and changes in bulimic cognitions. Reduction in vomit frequency was associated with weight history and with laxative or diuretic use. The implications for planning psychotherapeutic interventions in bulimia nervosa are discussed.

Adolescent↗

A double-blind placebo-controlled glucose challenge in bulimia nervosa: psychological effects.

Nineteen bulimic women and 22 age-matched controls were randomly assigned to receive 25 g of glucose or a placebo injection under double-blind conditions. Blood samples of glucose, insulin, and glucagon, and psychometric assessments of mood and food cravings were obtained 10 min before, and 0, 5, 10, 20, 30, 45, and 60 min after injection. Blood levels of the large neutral amino acids (LNAAs) tryptophan, tyrosine, leucine, valine, phenylalanine, and leucine were determined at 10 min before and 60 min after the injection. Bulimic subjects were found to report more symptoms of distressed mood throughout the entire monitoring period than controls. Five minutes following glucose ingestion the self-reports of depression, fatigue, anxiety, and bewilderment rose to a level among the bulimic subjects that was above that at baseline, and was higher than that of bulimia nervosa (BN) subjects receiving placebo. No comparable change in mood was observed among controls. Blood glucose levels were correlated with mood in the bulimic group, but not in controls. In addition, the glucose injection induced a heightened urge to binge in the bulimic group (compared to placebo at 10 and 60 min), whereas reducing food cravings (for sweets) in the controls (at 5 min). When collapsed across time and injection condition, the blood glucose level of bulimics was lower than that of controls. There were no differences in insulin response between the groups. The bulimic group was found to have lower baseline levels of blood tryptophan, whereas no differences in the tryptophan/LNAA ratio were observed either at baseline or following glucose.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Validity of the computerized DIS for diagnosing psychiatric inpatients.

The validity of a self-administered, computerized version of the National Institute of Mental Health Diagnostic Interview Schedule (DIS) was evaluated with a group of 41 psychiatric inpatients. Each patient was administered the computerized DIS (C-DIS) and a semi-structured clinical interview using the symptom checklist developed by Helzer et al. The concordance between the C-DIS and symptom checklist was comparable to that found in earlier studies of the original DIS. The overall distribution of kappas was also similar to those of previous studies. Overall, the results suggest that computerized administration may be a feasible alternative to face-to-face administration of the DIS.

Adolescent↗

The independence of hyperactivity from conduct disorder: methodological considerations.

It has been claimed that the childhood behavioural factors "hyperactivity" and "conduct disorder" are highly correlated. The fact that hyperactive symptoms load heavily on the conduct disorder factor has also been used to support the notion that hyperactivity is not an independent behavioural dimension. The present study employs a large sample of combined clinic and normal children to demonstrate that both of these observations are artifacts of methodological technique. When factor score coefficients are used to interpret factors, the hyperactive symptoms do not load on the conduct disorder factor. If factor scores are defined by the use of unit weights, as in previous studies, then the intercorrelation between the hyperactive and conduct disorder factors is high. The use of factor score coefficients to define factors, on the other hand, produces uncorrelated factors. The results support the idea that hyperactivity and conduct disorder are independent behavioural dimensions.

Adolescent↗

Computerized administration of the Diagnostic Interview Schedule.

The National Institute of Mental Health (NIMH) Diagnostic Interview Schedule (DIS) is a highly structured interview designed to be administered by lay interviewers and to yield psychiatric diagnoses. While the DIS has been used widely in large research centers, its use has been limited due to its complexity and need for extensive training to administer. In the present study 100 volunteers consisting of 80 psychiatric patients and 20 normal controls completed a self-administering computerized version of the DIS on two occasions. A standardized Computer Attitude Scale (CAS) was administered to each volunteer before the first and after the second computerized DIS (C-DIS). The C-DIS yielded acceptable test-retest reliability. Certain diagnoses were found to yield high test-retest reliability while reliability was lower for others. This general pattern was similar to the results of previous procedural validity studies. Patients found the C-DIS generally easy to use and operate, and after using the C-DIS, felt that their level of expertise in using computers had improved. Generally, the results support the use of computerized administration of the DIS.

Adult↗

Treatment of bulimia with fenfluramine and desipramine.

Desipramine and fenfluramine were administered to bulimic patients in a 15-week study of double-blind, placebo-controlled, crossover design. The 22 patients in the study met DSM-III criteria for bulimia and were of normal weight. Twelve subjects were randomly allocated to the fenfluramine group, and 10 subjects received desipramine. Half the subjects in each group received the active drug in the first 6 weeks and half received placebo. There was a 3-week washout period, after which subjects were crossed over for the remaining 6 weeks. The Eating Disorder Inventory, profile of Mood States, bulimia symptom checklists, and Hopkins Symptom Checklist were administered at weeks 0, 2, 4, 6, 9, 11, 13, and 15. Subjects maintained a daily record of bingeing, vomiting, and laxative/diuretic abuse. Results indicated that both drugs had beneficial effects on bingeing and vomiting frequency, although a greater proportion of patients were identified who responded to fenfluramine than to desipramine. Fenfluramine and desipramine were also effective in reducing the psychological symptoms of bulimia, such as the urge to binge, and feelings of depression. Results suggest that direct alteration of central food intake regulatory centers can effectively control bulimia.

Adolescent↗

Piracetam and event-related potentials in dyslexic males.

The effect of piracetam on visual event-related potentials (ERP) was investigated in a double-blind placebo-controlled study. Eight- to 12-year-old dyslexic males were randomly assigned to 3.3 g/day of piracetam or matching placebo in two divided doses over a 12-week period. Children performed a vigilance task in which they pressed a key when two alphabetic letters or shapes occurred in sequence. ERPs to letters and shapes, for active and passive responses, were recorded at the vertex and left and right parietal areas of the scalp. Performance measures included letter- and form-hits, misses, commission errors and reaction times. Piracetam increased the amplitude of a late positive component (believed to correspond to P300) at the vertex for letter-hits. Piracetam also increased the latency of this component in both hemispheres, but only for active responses (letter-hits) in the left hemisphere and passive responses (correct rejections and misses) in the right hemisphere. Although piracetam did not significantly affect performance, reaction time to letter-hits was significantly correlated with the latency of the P300 component, suggesting that letters created increased effort or attentional demand on the subjects compared with forms. An early ERP component (P225) also showed increased amplitude to piracetam in both hemispheres and effects were limited to form-hits. These effects were thought to possibly reflect slow negative potentials arising from stimulus anticipation in the CNV-like paradigm. In view of the small sample size, the results were cautiously interpreted as indicating a facilitation of verbal processing mechanisms responsible for analyzing the verbal significance of visual stimuli.

Brain↗

Nutritional effects on behavior of children.

Studies of nutritional effects on behavior of children present many of the same methodological problems as studies of drugs on behavior of children. Dependent measures must be made across several classes of response at different time scales and levels of precision. A schema is presented for an integrated series of nutritional studies. The effects of missing breakfast and of simple sugars are used to illustrate several applications from this schema, including autonomic (evoked cardiac response), central (event-related potentials), and behavioral measures. Each class of measures is found to be sensitive to these nutritional manipulations. Attention and motor behavior appear to be quite sensitive to subtle nutritional effects.

Attention↗