Study of behavioral phenotypes: goals and methodological considerations.

The study of behavioral phenotypes associated with genetic syndromes has gained increasing momentum over the past two decades. In this paper, the definition of behavioral phenotypes is presented and the complexities and obstacles to progress in this field are summarized. Also described are the goals of such investigations, including the need for syndrome delineation, provision of guidance for clinical management, contributions to understanding brain-behavior relations, advancements in developmental theory, and gaining understanding of the genetic bases of behavior. Methodological issues addressed in relation to such goals include the need for cross-disciplinary collaboration, concerns regarding sampling methods and comparison group selection, and developmental considerations. The complexity of cognitive abilities, the limitations of existing tests and measures, and ways of approaching the study of behavior are discussed. A final comment concerns the potential risks of research in behavioral phenotypes.

Very superior intelligence in a child with Noonan syndrome.

Psychological assessment documents very superior intelligence in a child with Noonan syndrome.

Language and behavior in children with Sotos syndrome.

OBJECTIVE: To examine language and behavior in children with Sotos syndrome, an overgrowth syndrome involving advanced bone age, characteristic facies, and developmental disability. METHOD: Twenty-seven children with Sotos syndrome were compared with 20 children with overgrowth, intellectual disability, and facies not characteristic of Sotos syndrome. Ages ranged from 5 to 16 years. Direct assessment was undertaken with standardized measures of intelligence and language abilities. Behavior was examined by parent and teacher report. RESULTS: Children with Sotos syndrome had levels of intelligence in the severely disabled to average range, with the majority falling in the borderline range. Mean level of intelligence was significantly higher than that observed for children in the comparison group. Language abilities were developed to a level consistent with overall level of intelligence. Rates of parent- and teacher-reported behavior problems were significantly higher than normal, but, with the exception of temper tantrums, did not differ from those observed in children in the comparison group. Attention-deficit hyperactivity disorder was observed in 38% of children with Sotos syndrome. They were more irritable and had more stereotypic behavior and inappropriate speech than is expected in children with intellectual disabilities, and they were more withdrawn and had more stereotypic behavior than children in the comparison group. CONCLUSIONS: Assessment of language abilities revealed no specific language impairment. High rates of behavior problems were observed, but these were not higher than those observed for other large, delayed, dysmorphic children.

Mitochondrial function in brain tissue in primary degenerative dementia.

Previous in vitro and in vivo studies of the brain in Alzheimer's disease indicated alterations in metabolism related to energy production although the relationships between these changes remains obscure. To help resolve this issue, in vitro oxygen uptake by homogenates of fresh samples of frontal neocortex from patients with dementia and neurosurgical controls has been examined as a measure of energy-related metabolism and mitochondrial function. Maximal respiratory rates (measured in the presence of an uncoupling agent) were similar for samples from 7 controls, 5 patients with Alzheimer's disease and two patients diagnosed clinically as Pick's disease, suggesting that there was little or no effect of these dementias on the maximal metabolic capacity of the tissue. However, under some conditions producing sub-maximal metabolic activity (which are of potentially greater physiological relevance) oxygen uptake rates were significantly elevated in the dementia group. The ratio of oxygen uptake rates in the presence and absence of ADP was significantly reduced (to 58% of control; P less than 0.02) for the dementia patients compared with controls, possibly indicative of partial mitochondrial uncoupling. These results indicate metabolic changes expressed in vitro which may be relevant to the pathogenesis of Alzheimer's disease and some related dementias.

Human figure drawings of gender-problem children: a comparison to sibling, psychiatric, and normal controls.

The Draw-a-Person test was used to evaluate a number of questions regarding children referred for potential problems in their gender-identity development (N = 36). Sibling (N = 31), psychiatric (N = 23), and normal (N = 30) children served as comparison groups. The major results included the following: (1) The gender-referred children were more likely to draw an opposite-sex person when requested to "draw a person" than were the other three groups; (2) the gender-referred children who drew an opposite-sex person were more likely to play with opposite-sex toys and dress-up apparel on a free-play task than were the gender-referred children who drew a same-sex person; (3) the gender-referred children drew taller opposite-sex persons than same-sex persons; (4) using Koppitz's (1968) criteria, the normal children had a smaller proportion of emotional disturbance indicators in their same-sex drawings than did the other three groups. These findings were discussed with regard to psychometric and interpretive issues in the assessment of children with atypical gender-role behavior.

A window for the study of prenatal sex hormone influences on postnatal development.

In humans, the influence of prenatal sex hormones on the fetal brain and subsequent postnatal development has had limited study because of the apparent inaccessibility of hormone levels in normal fetuses. We propose that amniotic fluid obtained via midtrimester amniocentesis can be assayed for fetal hormone levels during the period thought to be important for sexual differentiation of the brain. Amniotic fluid samples from midgestation (N = 70) were assayed for levels of testosterone and follicle-stimulating hormone, and significant sex differences were observed (ps less than .001), with some degree of overlap between the sexes. The possibility of applying hormone levels obtained from amniotic fluid to the study of postnatal development is discussed.

Voices from the trenches: nurses' experiences of hospital restructuring in Ontario.

Nurses, the largest occupational group in health care, have been disproportionately affected by health care restructuring initiatives. A survey of registered nurses in Ontario was conducted in the fall of 1998 to examine factors influencing their work life quality in hospital settings. As a part of this survey, respondents were provided with an opportunity to share their concerns about work conditions in an open ended section of the questionnaire. Almost sixty percent of the nurses chose to respond to the open ended question (n = 230), divided equally between males and females. The purpose of the qualitative component of the study was to obtain a more in depth analysis of the effects of hospital restructuring initiatives on staff nurses' working conditions. All geographic areas of the province were represented in the responses. A content analysis of the data was conducted to determine major themes. Similar themes were found across all geographic areas. The four major categories of concerns that emerged from the qualitative analysis were quality of worklife, quality of patient care, relations with management, and cumulative impact of work conditions on feelings and attitudes. Nurses' perceptions of their quality of work life, concern for the quality of patient care and their emotional and attitudinal responses were very similar to those reported in a recent study of hospital staff nurses in the United States. The decade of the 1990's has been characterized as one of constant change bordering on chaos within the health care system in Canada and the United States. In Canada, government fiscal policies have resulted in less money being directed toward health care forcing the system to reorganize in order to meet new financial realities. Many of the organizing efforts have been directed toward the acute care sector of the health care system. Nurses, as the largest occupational group within the health care system, have been disproportionately affected by these efforts. The purpose of this study was to tap nurses concerns about the effects of these changes on their personal and work experiences.

Amniotic fluid and midtrimester amniocentesis: a review.

The potential risks of midtrimester amniocentesis resulting from the loss of amniotic fluid are reviewed. Amniotic fluid fulfils important functions in fetal well-being, but its replacement time after amniocentesis is not known. A review of experimental amniocentesis in animals suggests risks to limbs and structural changes in fetal lungs. In humans, orthopaedic abnormalities and respiratory difficulties appear to be a risk of amniocentesis, and studies addressing these risks are also reviewed. Continued investigation of risks from fluid loss at midtrimester amniocentesis is recommended.

The antecedents and consequences of empowerment: a gender analysis.

Kanter argues that empowerment has many positive consequences. Not only do empowered employees work more effectively, but they are more likely to express positive attitudes toward their organization. Although support for Kanter's model has been found in several studies of nurses, these studies have not explored the possibility of gender differences. Do men in nursing have the same access as women do to structures that lead to empowerment? Moreover, do men and women react differently to empowerment? To answer these questions, we sampled 412 nurses (195 men; 217 women) about their access to empowerment structures and their trust and commitment to their organization. We found no support for the suggestion that male nurses are less empowered because of their "token" status. Also, we found that the model predicted the responses of men and women equally. Our results suggest that empowerment provides an excellent way of enhancing organizational attitudes for both men and women.

Calcium transport ATPase of canine cardiac sarcoplasmic reticulum. A comparison with that of rabbit fast skeletal muscle sarcoplasmic reticulum.

To define the mechanism responsible for the slow rate of calcium transport by cardiac sarcoplasmic reticulum, the kinetic properties of the Ca2+-dependent ATPase of canine cardiac microsomes were characterized and compared with those of a comparable preparation from rabbit fast skeletal muscle. A phosphoprotein intermediate (E approximately P), which has the stability characteristics of an acyl phosphate, is formed during ATP hydrolysis by cardiac microsomes. Ca2+ is required for the E approximately P formation, and Mg2+ accelerates its decomposition. The Ca2+ concentration required for half-maximal activation of the ATPase is 4.7 +/- 0.2 muM for cardiac microsomes and 1.3 +/- 0.1 muM for skeletal microsomes at pH 6.8 and 0 degrees. The ATPase activities at saturating concentrations of ionized Ca2+ and pH 6.8, expressed as ATP hydrolysis per mg of protein, are 3 to 6 times lower for cardiac microsomes than for skeletal microsomes under a variety of conditions tested. The apparent Km value for MgATP at high concentrations in the presence of saturating concentrations of ionized Ca2+ is 0.18 +/- 0.03 ms at pH 6.8 and 25 degrees. The maximum velocity of ATPase activity under these conditions is 0.45 +/- 0.05 mumol per mg per min for cardiac microsomes and 1.60 +/- 0.05 mumol per mg per min for skeletal microsomes. The maximum steady state level of E approximately P for cardiac microsomes, 1.3 +/- 0.1 nmol per mg, is significantly less than the value of 4.9 +/- 0.2 nmol per mg for skeletal microsomes, so that the turnover number of the Ca2+-dependent ATPase of cardiac microsomes, calculated as the ratio of ATPase activity to the E approximately P level is similar to that of the skeletal ATPase. These findings indicate that the relatively slow rate of calcium transport by cardiac microsomes, whem compared to that of skeletal microsomes, reflects a lower density of calcium pumping sites and lower Ca2+ affinity for these sites, rather than a lower turnover rate.

Organizational trust and empowerment in restructured healthcare settings. Effects on staff nurse commitment.

In today's dramatically restructured healthcare work environments, organizational trust is an increasingly important element in determining employee performance and commitment to the organization. The authors used Kanter's model of workplace empowerment to examine the effects of organizational trust and empowerment on two types of organizational commitment. A predictive, nonexperimental design was used to test Kanter's theory in a random sample of 412 Canadian staff nurses. Empowered nurses reported higher levels of organizational trust, which in turn resulted in higher levels of affective commitment. However, empowerment did not predict continuance commitment--that is, commitment to stay in the organization based on perceived lack of other job opportunities. Because past research has linked affective commitment to employee productivity, these results suggest that fostering environments that enhance perceptions of empowerment and organizational trust will have positive effects on organizational members and increase organizational effectiveness.

Mental rotation at 7 years: relations with prenatal testosterone levels and spatial play experiences.

Biological and social-experiential factors appear to play a role in the male advantage in spatial abilities. In the present study, relations among prenatal testosterone levels, spatial play experiences, and mental rotation task performance were explored in 7-year-old boys and girls. A positive correlation was observed between prenatal testosterone levels and rate of rotation in girls. The findings were less clear for boys, but suggested the opposite pattern of results. Relations between spatial play preferences and mental rotation task performance were not observed in children of either sex. These findings are consistent with the hypothesis that testosterone acts on the fetal brain to influence the development of spatial ability.

The impact of workplace empowerment, organizational trust on staff nurses' work satisfaction and organizational commitment.

A predictive, nonexperimental design was used to test Kanter's work empowerment theory in a random sample of 412 staff nurses selected from the professional registry list of a central Canadian province. Kanter argues that work environments that provide access to information, support, resources, and opportunity to learn and develop are empowering and influence employee work attitudes, productivity, and organizational effectiveness. Test results suggest that fostering environments that enhance perceptions of empowerment will have positive effects on organizational members and increase organizational effectiveness.

Testing Karasek's Demands-Control Model in restructured healthcare settings: effects of job strain on staff nurses' quality of work life.

BACKGROUND: Job strain among staff nurses has become an increasingly important concern in relationship to employee performance and commitment to the organization in current restructured healthcare settings. OBJECTIVES: The purpose of this study was to test Karasek's Demands-Control Model of job strain by examining the extent to which the degree of job strain in nursing work environments affects staff nurses' perceptions of structural and psychological empowerment, work satisfaction, and organizational commitment. METHOD: A predictive, nonexperimental design was used to test these relationships in a random sample of 404 Canadian staff nurses. Karasek's Job Content Questionnaire, the Conditions of Work Effectiveness Questionnaire-II, Spreitzer's Psychological Empowerment Questionnaire, Meyer and Allen's Organizational Commitment Questionnaire, and the Global Satisfaction Scale were used to measure the major study variables. RESULTS: Nurses with higher level of job strain were found to be significantly more empowered, more committed to the organization, and more satisfied with their work. CONCLUSIONS: Support for Karasek's Demands/Control theory was established in this study.

Impact of structural and psychological empowerment on job strain in nursing work settings: expanding Kanter's model.

OBJECTIVE: In this study, we tested an expanded model of Kanter's structural empowerment, which specified the relationships among structural and psychological empowerment, job strain, and work satisfaction. BACKGROUND: Strategies proposed in Kanter's empowerment theory have the potential to reduce job strain and improve employee work satisfaction and performance in current restructured healthcare settings. The addition to the model of psychological empowerment as an outcome of structural empowerment provides an understanding of the intervening mechanisms between structural work conditions and important organizational outcomes. METHODS: A predictive, nonexperimental design was used to test the model in a random sample of 404 Canadian staff nurses. The Conditions of Work Effectiveness Questionnaire, the Psychological Empowerment Questionnaire, the Job Content Questionnaire, and the Global Satisfaction Scale were used to measure the major study variables. RESULTS: Structural equation modelling analyses revealed a good fit of the hypothesized model to the data based on various fit indices (chi 2 = 1140, df = 545, chi 2/df ratio = 2.09, CFI = 0.986, RMSEA = 0.050). The amount of variance accounted for in the model was 58%. Staff nurses felt that structural empowerment in their workplace resulted in higher levels of psychological empowerment. These heightened feelings of psychological empowerment in turn strongly influenced job strain and work satisfaction. However, job strain did not have a direct effect on work satisfaction. CONCLUSIONS: These results provide initial support for an expanded model of organizational empowerment and offer a broader understanding of the empowerment process.

Altered metabolic properties of cultured skin fibroblasts in Alzheimer's disease.

Alzheimer's disease is associated with selective neuronal loss, the cause of which is undetermined. Evidence indicating a predisposing genetic factor associated with this disease suggests that important alterations may be expressed in tissues other than the brain. Because abnormal glucose and energy-related metabolism have been identified in both in vivo and in vitro studies of brain, we conducted a study to examine related measures in cultured skin fibroblasts from six patients with Alzheimer's disease and seven age-matched controls. After 60 minutes' incubation, the production of 14CO2 from [U-14C]glucose and lactate production were significantly higher in the cells from the group of patients with Alzheimer's disease. The increase of 14CO2 production, but not the production of lactate, was most evident after a more rapid period of metabolic activity in the first 10 minutes of incubation. By contrast, 14CO2 production from [U-14C]glutamine, which is probably the major substrate of oxidative metabolism in these cells, was significantly reduced in the Alzheimer's disease cells following longer (120-minute) incubations. Oxygen uptake by cell suspensions was also significantly reduced in the group with Alzheimer's disease. These results indicate that complex metabolic differences are expressed in nonneural tissues from some patients with Alzheimer's disease and may provide important clues to the pathogenesis of this disorder.

Effects of postdecapitative ischemia on mitochondrial respiration in brain tissue homogenates.

Mitochondria isolated from ischemic brain characteristically show changes in respiratory function. As conventional procedures for mitochondrial isolation yield a subpopulation of the total population and require extensive manipulation, it is unclear to what extent these changes are representative of mitochondria in the unfractionated tissue. We previously showed that the oxygen uptake by unfractionated forebrain homogenates, measured under two different sets of incubation conditions, provided information on some aspects of the respiratory activity of both the free and synaptosomal pools of mitochondria. Forebrain homogenates from animals subjected to 30 min of postdecapitative ischemia exhibited large reductions in oxygen uptake rates measured in a high K+ (mitochondrial) buffer in the presence of either ADP (44% of control values) or an uncoupling agent (45% of control values). These reductions in respiratory activity were comparable to alterations observed under the same conditions for mitochondria isolated from the ischemic brains. Similar alterations were seen in homogenates from three subregions: neocortex, hippocampus, and striatum. In a physiological buffer, in which oxygen uptake by homogenates largely resulted from activity of mitochondria within synaptosomes, there was little or no change in basal glucose-supported rates (79-96% of control values) and small reductions in maximal rates (63-81% of control values) measured in the presence of an uncoupling agent. These results suggest that alterations of respiratory function seen in isolated free mitochondria provide appropriate estimates of the dysfunction in the total free mitochondrial pool but that synaptosomal mitochondria may be less affected. Measurements of respiratory function of isolated synaptosomes from ischemic tissue provided further support for the relative preservation of synaptosomal mitochondria during ischemic insult.

Two subgroups of gender-problem children.

Gender-referred children who met the DSM-III diagnostic criteria for gender identity disorder of childhood (n = 21) and gender-referred children who did not meet these criteria (n = 15) were compared with regard to demographic, gender role, and behavioral disturbance information. As judged by parental questionnaires and behavioral tests, the cross-gender role behavior of gender-referred children who met the DSM-III criteria was generally more extreme than that of their non-DSM-III counterparts. These two diagnostically defined subgroups did not, however, differ in the degree of their behavioral and emotional disturbance. The DSM-III children were significantly younger than the non-DSM-III children, but the extent to which the disparity in age accounted for the gender role differences appeared equivocal. The implications of these findings for the diagnosis and assessment of gender-referred children are discussed.

The Play Activity Questionnaire: a parent report measure of children's play preferences.

Three studies describe the development and validation of the Play Activity Questionnaire (PQ), a parent report measure of children's play preferences. In Study 1, the 15-item PQ was completed by parents of 239 6- to 8-year-old children, and exploratory factor analysis revealed four play factors: Active and Adventurous, Athletic, Rough-and-Tumble, and Quiet. In Study 2, the factor structure was replicated with PQ data on 203 children of a broader age range (4 to 12 years). The play factors accounted for 65.7% of the variance. Boys' scores exceeded girls' scores on the Athletic and Rough-and-Tumble play factors. Girls' scores exceeded boys' scores on the Quiet play factor. Sex differences were not observed on the Active and Adventurous play factor. Interparent agreement was moderately high, and PQ factor scores were unrelated to social class or nationality. Individual factor scores showed moderate to high stability over 5 months. Validity of the play factors was examined in Study 3 by relating factor scores to measures of activity level, aggression, and sex-typed play. Play factor scores were associated with several of these measures, suggesting that the PQ is a valid measure of children's play behavior with potential applications in the fields of developmental psychopathology and psychoneuroendocrinology, and in studies of normal play and sex-role development.