Phobic anxiety in 11 nations: Part I: Dimensional constancy of the five-factor model

The Fear Survey Schedule-III (FSS-III) was administered to a total of 5491 students in Australia, East Germany, Great Britain, Greece, Guatemala, Hungary, Italy, Japan, Spain, Sweden, and Venezuela, and submitted to the multiple group method of confirmatory analysis (MGM) in order to determine the cross-national dimensional constancy of the five-factor model of self-assessed fears originally established in Dutch, British, and Canadian samples. The model comprises fears of bodily injury-illness-death, agoraphobic fears, social fears, fears of sexual and aggressive scenes, and harmless animals fears. Close correspondence between the factors was demonstrated across national samples. In each country, the corresponding scales were internally consistent, were intercorrelated at magnitudes comparable to those yielded in the original samples, and yielded (in 93% of the total number of 55 comparisons) sex differences in line with the usual finding (higher scores for females). In each country, the relatively largest sex differences were obtained on harmless animals fears. The organization of self-assessed fears is sufficiently similar across nations to warrant the use of the same weight matrix (scoring key) for the FSS-III in the different countries and to make cross-national comparisons feasible. This opens the way to further studies that attempt to predict (on an a priori basis) cross-national variations in fear levels with dimensions of national cultures. (C) 2002 Elsevier Science Ltd. All rights reserved.

A comprehensive analysis of sexual dimorphism in the midbrain dopamine system

Thesis (Ph.D.)--University of Washington, 2016-06

Age-at-first-registration and heterogeneity in affective psychoses

Background: Previous research into age of onset in affective disorders has produced conflicting results. This paper examines the influence of heterogeneity on the age-at-first-registration distribution for the ICD-9 diagnostic group 'affective psychosis'. Method: For 1979-1991, data for age-at-first-registration for 4985 individuals diagnosed with affective psychosis (ICD-9 296.x) were extracted from a name-linked mental health register. These data were divided into (i) '296.1 only', a category used to code unipolar depression (males = 700; females = 1321); and (ii) '296 other', all 296 cases other than 296.1 (males = 1280; females = 1684). Inception rates for each 5-year age division were adjusted for the background population age-structure as a rate per 100 000 population. Results: The age-at-first-registration distribution for affective psychosis has a wide age range, with women outnumbering men. There is a near-linear increase in inception rates for both men and women with 296.1 only, while the bulk of those with affective psychoses (296 other) have an inverted U-shaped age distribution. Males have an earlier modal age-at-first-registration for 296 other compared to females. Conclusion: The heterogeneity in terms of subtypes and sex in affective psychosis clouds the interpretation of age-at-first-registration. Separating those with unipolar psychotic depression from other subclassifications and differentiating by sex may provide clues to factors that precipitate the onset of affective psychosis.

Gender diagnosticity and androgen receptor gene CAG repeat sequence

The gender diagnosticity (GD) approach of Lippa (1995) was used to evaluate the relationship of within-sex differences in psychological masculinity-femininity to a genetic characteristic, the length of a repeated CAG sequence in the X-linked androgen receptor (AR) gene. Previously assessed adult samples in Australia and Sweden were used for this purpose. A weak relationship (correlations in the range .11 to .14) was obtained in both countries. Additional data from adolescent twins from Australia (12-, 14-, 16-year-olds) did not confirm such a relationship at those ages, especially for males. The fact that this sample consisted of twins permitted two kinds of within-pair comparisons: (1) Did the dizygotic twin who had the longer AR sequence have the higher GD score? (2) Was one twin's GD score more highly correlated with the other twin's AR score in MZ than in DZ pairs? The answer in both cases was negative. Clarification of these relationships will require large samples and measurements at additional ages.

Sexual dimorphism of the femoral neck during the adolescent growth spurt: a structural analysis

Before puberty, there are only small sex differences in body shape and composition. During adolescence, sexual dimorphism in bone, lean, and fat mass increases, giving rise to the greater size and strength of the male skeleton. The question remains as to whether there are sex differences in bone strength or simply differences in anthropometric dimensions. To test this, we applied hip structural analysis (HSA) to derive strength and geometric indices of the femoral neck using bone densitometry scans (DXA) from a 6-year longitudinal study in Canadian children. Seventy boys and sixty-eight girls were assessed annually for 6 consecutive years. At the femoral neck, cross-sectional area (CSA, an index of axial strength), subperiosteal width (SPW), and section modulus (Z, an index of bending strength) were determined, and data were analyzed using a hierarchical (random effects) modeling approach. Biological age (BA) was defined as years from age at peak height velocity (PHV). When BA, stature, and total-body lean mass (TB lean) were controlled, boys had significantly higher Z than girls at all maturity levels (P < 0.05). Controlling height and TB lean for CSA demonstrated a significant independent sex by BA interaction effect (P < 0.05). That is, CSA was greater in boys before PHV but higher in girls after PHV The coefficients contributing the greatest proportion to the prediction of CSA, SPW, and Z were height and lean mass. Because the significant sex difference in Z was relatively small and close to the error of measurement, we questioned its biological significance. The sex difference in bending strength was therefore explained by anthropometric differences. In contrast to recent hypotheses, we conclude that the CSA-lean ratio does not imply altered mechanosensitivity in girls because bending dominates loading at the neck, and the Z-lean ratio remained similar between the sexes throughout adolescence. That is, despite the greater CSA in girls, the bone is strategically placed to resist bending; hence, the bones of girls and boys adapt to mechanical challenges in a similar way. (C) 2004 Elsevier Inc. All rights reserved.

Deletion of guanine nucleotide binding protein az subunit in mice induces a gene dose dependent tolerance to morphine

The Mechanism Underlying the development of tolerance to morphine, is still incompletely understood. Morphine binds to opioid receptors, Which in turn activates downstream second messenger cascades through heterotrimeric guanine nucleotide binding proteins (G proteins). In this paper, we show that G(z), a member of the inhibitory G protein family, plays an important role in mediating the analgesic and lethality effects of morphine after tolerance development. We blocked signaling through the G(z) second messenger cascade by genetic ablation of the alpha subunit of the G protein in mice. The Galpha(z) knockout Mouse develops significantly increased tolerance to morphine. which depends oil Galpha(z), gene dosage. Further experiments demonstrate that the enhanced morphine tolerance is not caused by pharmacokinetic and behavioural learning mechanisms. The results suggest that G(z) signaling pathways are involved ill transducing the analgesic and lethality effects of morphine following chronic morphine treatment. (C) 2004 Elsevier Ltd. All rights reserved.

The development of preferences for specific body shapes

Research with adults has shown a preference for average-weight female figures with waist-to-hip ratios (WHR) of 0.7, and average weight male figures with waist-to-hip ratios of 0.9. This study investigated the development of preferences for WHR sizes as well as preferences for specific body weights. Five-hundred eleven children ranging in age from 6 to 17 were presented with drawings of 12 male and 12 female silhouettes varying in weight and WHR and asked to select one they thought looked the nicest or most attractive. The youngest children showed preferences for the underweight figures, changing to consistent preferences for the average weight figures in the teenage years. The developmental curves for waist-to-hip ratio preferences were linear, changing gradually over time to become more adult-like. Potential developmental models for the development of preferences for specific body shapes are considered in relation to these data.

Statistical modeling and projections of lung cancer mortality in 4 industrialized countries

The purpose of this work was to model lung cancer mortality as a function of past exposure to tobacco and to forecast age-sex-specific lung cancer mortality rates. A 3-factor age-period-cohort (APC) model, in which the period variable is replaced by the product of average tar content and adult tobacco consumption per capita, was estimated for the US, UK, Canada and Australia by the maximum likelihood method. Age- and sex-specific tobacco consumption was estimated from historical data on smoking prevalence and total tobacco consumption. Lung cancer mortality was derived from vital registration records. Future tobacco consumption, tar content and the cohort parameter were projected by autoregressive moving average (ARIMA) estimation. The optimal exposure variable was found to be the product of average tar content and adult cigarette consumption per capita, lagged for 2530 years for both males and females in all 4 countries. The coefficient of the product of average tar content and tobacco consumption per capita differs by age and sex. In all models, there was a statistically significant difference in the coefficient of the period variable by sex. In all countries, male age-standardized lung cancer mortality rates peaked in the 1980s and declined thereafter. Female mortality rates are projected to peak in the first decade of this century. The multiplicative models of age, tobacco exposure and cohort fit the observed data between 1950 and 1999 reasonably well, and time-series models yield plausible past trends of relevant variables. Despite a significant reduction in tobacco consumption and average tar content of cigarettes sold over the past few decades, the effect on lung cancer mortality is affected by the time lag between exposure and established disease. As a result, the burden of lung cancer among females is only just reaching, or soon will reach, its peak but has been declining for I to 2 decades in men. Future sex differences in lung cancer mortality are likely to be greater in North America than Australia and the UK due to differences in exposure patterns between the sexes. (c) 2005 Wiley-Liss, Inc.

Anabolic responses to resistance training in older men and women: A brief review

Resistance training has been shown to be the most effective exercise mode to induce anabolic adaptations in older men and women. Advances in imaging techniques and histochemistry have increased the ability to detect such changes, confirming the high level of adaptability that remains in aging skeletal muscle. This brief review presents a summary of the resistance-training studies that directly compare chronic anabolic responses to training in older (> 60 years) men and women. Sixteen studies are summarized, most of which indicate similar relative anabolic responses between older men and women after resistance training. Relatively small sample sizes in most of the interventions limited their ability to detect significant sex differences and should be considered when interpreting these studies. Future research should incorporate larger sample sizes with multiple measurement time points for anabolic responses.

Myths and plain truths about schizophrenia epidemiology - the NAPE lecture 2004

Objective: Science needs to constantly match research models against the data. With respect to the epidemiology of schizophrenia, the widely held belief that the incidence of schizophrenia shows little variation may no longer be supported by the data. The aims of this paper are (i) to explore data-vs.-belief mismatch with respect to the incidence of schizophrenia, and (ii) to speculate on the causes and consequences of such discrepancies. Method: Based on a recently published systematic review of the incidence of schizophrenia, the distribution of incidence rates around the world was examined. In order to examine if the incidence of schizophrenia differed by sex, male vs. female risk ratios were generated. Results: The distribution of incidence rates for schizophrenia is asymmetrical with many high rates skewing the distribution. Based on the central 80% of rates, the incidence of schizophrenia varies in a five-fold range (between 7.7 and 43.0 per 100 000). Males have a significantly higher incidence of schizophrenia compared with females (median male to female risk ratio = 1.4), and this difference could not be accounted for by diagnostic criteria or age range. Conclusion: The beliefs that (i) the incidence of schizophrenia does not vary between sites and (ii) males and females are equally affected, may have persisted because of an unspoken deeper belief that schizophrenia is an egalitarian and exceptional disorder. Our ability to generate productive hypotheses about the aetiology of schizophrenia rests on an accurate appraisal of the data. Beliefs not supported by data should be identified and relabelled as myths.

Influence of gender on mental health literacy in young Australians

Objectives: To determine the effects of gender on mental health literacy in young people between 12 and 25 years of age. Design: Computer-Assisted Telephone Interviewing was employed to conduct a cross-sectional structured interview focusing on young people's awareness of depression and psychosis. Participants: The sample comprised 1207 young Australians (539 males and 668 females) between the ages of 12-25 recruited from two metropolitan and two regional areas within Victoria. Six hundred and six respondents were presented a depression vignette and 601 were presented a psychosis vignette. Results: Female respondents (60.7%) were significantly more likely to correctly identify depression in the vignette as compared to male respondents (34.5%). No significant gender differences were noted for the psychosis vignette. Males were less significantly likely to endorse seeing a doctor or psychologist/counsellor for the treatment of psychosis. Males were also significantly more likely than females to endorse alcohol as a way of dealing with depression and antibiotics as useful for dealing with psychosis. Conclusion: Gender differences in mental health literacy are striking. Males showed significantly lower recognition of symptoms associated with mental illness and were more likely endorse the use alcohol to deal with mental health problems. Such factors may contribute to the delays in help seeking seen in young males. Further research is needed to delineate how these gender differences in young people may obstruct help seeking, early intervention and other aspects of mental health service delivery.

Genetic and Cultural Transmission of Smoking Initiation: An Extended Twin Kinship Model

Background Considerable evidence from twin and adoption studies indicates that genetic and shared environmental factors play a significant role in the initiation of smoking behavior. Although twin and adoption designs are powerful to detect genetic and environmental influences, they do not provide information on the processes of assortative mating and parent–offspring transmission and their contribution to the variability explained by genetic and/or environmental factors. Methods We examined the role of genetic and environmental factors for smoking initiation using an extended kinship design. This design allows the simultaneous testing of additive and non-additive genetic, shared and individual-specific environmental factors, as well as sex differences in the expression of genes and environment in the presence of assortative mating and combined genetic and cultural transmission. A dichotomous lifetime smoking measure was obtained from twins and relatives in the Virginia 30,000 sample. Results Results demonstrate that both genetic and environmental factors play a significant role in the liability to smoking initiation. Major influences on individual differences appeared to be additive genetic and unique environmental effects, with smaller contributions from assortative mating, shared sibling environment, twin environment, cultural transmission and resulting genotype–environment covariance. The finding of negative cultural transmission without dominance led us to investigate more closely two possible mechanisms for the lower parent–offspring correlations compared to the sibling and DZ twin correlations in subsets of the data: (i) age × gene interaction, and (ii) social homogamy. Neither mechanism provided a significantly better explanation of the data, although age regression was significant. Conclusions This study showed significant heritability, partly due to assortment, and significant effects of primarily non-parental shared environment on smoking initiation.

Symptom prevalence and clustering of symptoms in people living with chronic hepatitis C infection

Quality of life has been shown to be poor among people living with chronic hepatitis C However, it is not clear how this relates to the presence of symptoms and their severity. The aim of this study was to describe the typology of a broad array of symptoms that were attributed to hepatitis C virus (HCV) infection. Phase I used qualitative methods to identify symptoms. In Phase 2, 188 treatment-naive people living with HCV participated in a quantitative survey. The most prevalent symptom was physical tiredness (86%) followed by irritability (75%), depression (70%), mental tiredness (70%), and abdominal pain (68%). Temporal clustering of symptoms was reported in 62% of participants. Principal components analysis identified four symptom clusters: neuropsychiatric (mental tiredness, poor concentration, forgetfulness, depression, irritability, physical tiredness, and sleep problems); gastrointestinal (day sweats, nausea, food intolerance, night sweats, abdominal pain, poor appetite, and diarrhea); algesic (joint pain, muscle pain, and general body pain); and dysesthetic (noise sensitivity, light sensitivity, skin. problems, and headaches). These data demonstrate that symptoms are prevalent in treatment-naive people with HCV and support the hypothesis that symptom clustering occurs.

Real-time imaging of human cortical activity evoked by painful esophageal stimulation

Background & Aims: Current models of visceral pain processing derived from metabolic brain imaging techniques fail to differentiate between exogenous (stimulus-dependent) and endogenous (non-stimulus-specific) neural activity. The aim of this study was to determine the spatiotemporal correlates of exogenous neural activity evoked by painful esophageal stimulation. Methods: In 16 healthy subjects (8 men; mean age, 30.2 ± 2.2 years), we recorded magnetoencephalographic responses to 2 runs of 50 painful esophageal electrical stimuli originating from 8 brain subregions. Subsequently, 11 subjects (6 men; mean age, 31.2 ± 1.8 years) had esophageal cortical evoked potentials recorded on a separate occasion by using similar experimental parameters. Results: Earliest cortical activity (P1) was recorded in parallel in the primary/secondary somatosensory cortex and posterior insula (∼85 ms). Significantly later activity was seen in the anterior insula (∼103 ms) and cingulate cortex (∼106 ms; P = .0001). There was no difference between the P1 latency for magnetoencephalography and cortical evoked potential (P = .16); however, neural activity recorded with cortical evoked potential was longer than with magnetoencephalography (P = .001). No sex differences were seen for psychophysical or neurophysiological measures. Conclusions: This study shows that exogenous cortical neural activity evoked by experimental esophageal pain is processed simultaneously in somatosensory and posterior insula regions. Activity in the anterior insula and cingulate - brain regions that process the affective aspects of esophageal pain - occurs significantly later than in the somatosensory regions, and no sex differences were observed with this experimental paradigm. Cortical evoked potential reflects the summation of cortical activity from these brain regions and has sufficient temporal resolution to separate exogenous and endogenous neural activity. © 2005 by the American Gastroenterological Association.

Sociolinguistic variability in oral narrative.

This thesis begins with a sociolinguistic correlational study of three phonetic variables - (h), (t) and (ing) - as used by four occupational groups - nurses, chefs, hairdressers and taxi-drivers. The groups were selected to incorporate three independent variables: sex (male-dominated versus female-dominated occupations); training (length and specialisation - nurses and chefs being more specialised than hairdressers and taxi-drivers) and location (the populations were selected from two cities - Liverpool and Birmingham). Although the correlational work demonstrates intra-sex and occupation consistency in speakers' choice of linguistic variants (females (particularly nurses) being significantly closer to the prestige norm), it is essentially non-explanatory and cannot accout for narrative dynamics and style shift. Therefore, an in-depth qualitative examination of the data (which draws mainly on Narrative and Discourse Analysis) forms the major part of the analysis. The study first analyses features common to all the narratives, direct speech, expressive phonology and linguistic ambiguity emerging as characteristic of all humorous storytelling. Secondly, three major sources of inter-personal variation are invetigated: narrator perspective, sex and occuptational role. Perspective is found to vary with topic and personality, greater narrator involvement coinciding with a higher proportion of internal evaluation devices. Sex differences include topic choice and bonding in the storytelling sessions. Sex differences are also evident in style shifting, where the narrator mimics the voice of a character in the narrative (aodpting segmental and/or prosodic tokens to signal a change of persona). The research finds that female narrators rarely employ segmental accommodation downwards on the social scale (whereas men do), but are on the other hand adept at using prosodic effects for mimicry. Taxi-drivers emerge as the group with the most distinctive narrative flair, a fact which is related to their occupation. The conclusion stresses a need for both quantitative and qualitative approaches to data; the importance of occupational role, as opposed to sex role per se in determining narrative conventions; the view of narrative as a negotiable entity, which is the product of relationships among participants; and the importance of considering the totality of the communicative act.