Cerebral activations during viewing of food stimuli in adult patients with acquired structural hypothalamic damage: a functional neuroimaging study.

BACKGROUND/OBJECTIVES: Obesity is common following hypothalamic damage due to tumours. Homeostatic and non-homeostatic brain centres control appetite and energy balance but their interaction in the presence of hypothalamic damage remains unknown. We hypothesized that abnormal appetite in obese patients with hypothalamic damage results from aberrant brain processing of food stimuli. We sought to establish differences in activation of brain food motivation and reward neurocircuitry in patients with hypothalamic obesity (HO) compared with patients with hypothalamic damage whose weight had remained stable. SUBJECTS/METHODS: In a cross-sectional study at a University Clinical Research Centre, we studied 9 patients with HO, 10 age-matched obese controls, 7 patients who remained weight-stable following hypothalamic insult (HWS) and 10 non-obese controls. Functional magnetic resonance imaging was performed in the fasted state, 1 h and 3 h after a test meal, while subjects were presented with images of high-calorie foods, low-calorie foods and non-food objects. Insulin, glucagon-like peptide-1, Peptide YY and ghrelin were measured throughout the experiment, and appetite ratings were recorded. RESULTS: Mean neural activation in the posterior insula and lingual gyrus (brain areas linked to food motivation and reward value of food) in HWS were significantly lower than in the other three groups (P=0.001). A significant negative correlation was found between insulin levels and posterior insula activation (P=0.002). CONCLUSIONS: Neural pathways associated with food motivation and reward-related behaviour, and the influence of insulin on their activation may be involved in the pathophysiology of HO.

Influence of life-history variation on the genetic structure of two sympatric salamander taxa.

Life-history characteristics are an important determinant of a species' dispersal abilities. We predict that variation in life history can influence population-level genetic patterns. To test this prediction, we estimate population-level genetic structure for two sympatric species of stream-breeding salamander. The Cope's giant salamander (Dicamptodon copei) rarely metamorphoses into a terrestrial adult, thereby limiting overland dispersal and potentially gene flow. In contrast, the Pacific giant salamander (D. tenebrosus) commonly metamorphoses, which is expected to facilitate overland dispersal and gene flow. Three sets of analyses based on microsatellite data support these hypotheses, showing that D. tenebrosus displays minimal population-level genetic structuring and no pattern of isolation by distance, whereas D. copei displays a high degree of population-level genetic structure and significant isolation by distance. Specifically, nearly all pairwise F(ST )values were significantly different from 0 between populations of D. copei, with fewer than half the pairwise F(ST )values significant from 0 in D. tenebrosus. Additionally, Structure analyses indicated eight genetic clusters for D. copei but only one genetic cluster for D. tenebrosus. Finally, Mantel tests showed significant correlations between stream and overland distance with genetic distance for D. copei but no significant correlations of either landscape feature for D. tenebrosus at the scale of the study. These results provide a case study of the link between life-history variation and population genetic patterns while controlling for phylogeny and environmental variation.

Origin of disc new vessels assessed by videofluorography.

Ten patients with disc neovascularisation of various aetiologies were studied to ascertain the origin of their new vessels. Fluorescein angiography was carried out with an image intensified video camera. A retinal artery derivation was demonstrated for the first time and was seen in three cases. Six further patients showed a retinal venous supply, and finally there was one from a choroidal source.

Traumatic myopia; an ultrasonographic and clinical study.

Three patients with transient myopia following blunt injury are described with the aid of serial ultrasonography. The cause of refractive change is an increase in the anteroposterior thickness of the crystalline lens, which probably results from oedema of the ciliary body.

Adolescents with physical disabilities: some psychosocial aspects of health.

PURPOSE: To examine the psychosocial issues related to growing up with a physical disability. METHODS: Adolescents with physical disabilities aged 11-16 years were compared with a Canadian national sample of adolescents using the Health Behaviours in School-Aged Children (HBSC), a World Health Organization Cross-National Study survey. RESULTS: Adolescents with physical disabilities reported good self-esteem, strong family relationships, and as many close friends as adolescents in the national sample. However, adolescents with physical disabilities participated in fewer social activities and had less intimate relationships with their friends. They had more positive attitudes toward school, teachers, and their fellow classmates than the national sample, but fewer had plans for postsecondary education. The majority of adolescents with physical disabilities reported that they had not received information on parenthood, birth control, and sexually transmitted diseases. CONCLUSIONS: There are a number of critical areas of risk for adolescents with physical disabilities to which health promotion efforts should be directed. These include lower levels of peer integration, heightened adult orientation, low educational aspirations, and poor knowledge of sexuality.

Polymorphic tetranucleotide microsatellites for Cope's giant salamander (Dicamptodon copei) and Pacific giant salamander (Dicamptodon tenebrosus).

We present primers and amplification conditions for 15 microsatellite loci developed for the Cope's giant salamander (Dicamptodon copei), 14 of which are tetranucleotide repeats. Cross-species amplification revealed 10 of these loci to also be polymorphic in the Pacific giant salamander (Dicamptodon tenebrosus). Several loci produced nonoverlapping allelic ranges between the two species and may be useful in species identification. These polymorphic microsatellite loci are potentially useful for future studies of population genetics in dicamptodontid salamanders.

Alcohol consumption and blood pressure: analysis of data from the Canada Health Survey.

Recent epidemiologic studies report a significant association between alcohol consumption and elevations in both systolic (SBP) and diastolic (DBP) blood pressures. To test this hypothesis, we conducted a multivariate analysis of physical examination and other data on 721 men and 697 women aged 20 or more collected during the Canada Health Survey in 1978-1979. SBP and DBP were considered as separate dependent variables in multiple regression models with the following independent variables: age, alcohol consumption (measured as a 7-day recall history and as an average frequency of consumption), serum cholesterol, plasma glucose, physical activity, Quetelet index, parental history of hypertension, cigarette consumption, income, education, and exogenous hormonal use in women. In both weighted and unweighted multiple regression analyses, we could not demonstrate for either sex, a significant association between alcohol consumption (as recorded and following quadratic and logarithmic transformations) and either SBP or DBP. For both sexes, only age and Quetelet index were highly significantly (P less than 0.0001) and consistently associated with both SBP and DBP. No other independent variables were consistently associated, for either sex, with SBP and DBP. Further, the dose-response patterns noted by other investigators suggesting either a positive and linear relationship or a curvilinear relationship were not found in either our univariate or multivariate analyses. Rather, the alcohol-blood pressure curves showed no consistent patterns of any kind in either sex. These findings do not support recent claims that alcohol consumption is a determinant of elevations in either SBP or DBP.

Deflazacort treatment of Duchenne muscular dystrophy.

OBJECTIVE: We report the long-term effects on muscle strength and side effects with deflazacort in Duchenne muscular dystrophy (DMD). STUDY DESIGN: Boys with DMD between the ages of 7 and 15 years were reviewed retrospectively; 30 had been treated with deflazacort, and 24 had not. Muscle function, pulmonary function, and side effects were compared. RESULTS: The boys not treated with deflazacort stopped walking at 9.8 +/-1.8 years. Seven of 30 treated boys had stopped walking at 12.3+/-2.7 years (P<.05), and of the 23 boys who were still walking, 21 were older than 10 years. Pulmonary function (percent predicted functional vital capacity) was significantly greater in treated boys at 15 years (88% +/- 18%) than in boys not treated (39%+/-20%) (P<.001). Between 9 and 15 years, treated boys were shorter. Between 9 and 13 years, treated boys weighed less. After 13 years the treated boys maintained their weight, whereas boys not treated lost weight. Asymptomatic cataracts developed in 10 of 30 boys who received deflazacort. Other potential side effects of deflazacort such as hypertension, glucosuria, acne, infection, or bruising were not more common. CONCLUSIONS: We conclude that deflazacort can preserve gross motor and pulmonary function in boys with DMD with limited side effects.