Search PubMed⌕ Search

Biomedical subjects

S G West

Publications and source records attributed to S G West.

At least 37 records · Page 2Linked to original sources

Confirmation of linkage of hereditary partial lipodystrophy to chromosome 1q21-22.

Familial lipodystrophy is a genetically heterogeneous set of disorders characterized by a total or partial absence of subcutaneous fat, diabetes mellitus or impaired glucose tolerance, hyperlipidemia, and hypermetabolism [Senior and Gellis, 1964]. One subtype, familial partial lipodystrophy Dunnigan (FPLD), is a rare autosomal dominant trait that results in an gradual loss of subcutaneous fat in the lower trunk and limbs, Type V hyperlipoproteinemia, hypertriglyceridemia, and insulin-resistant diabetes. Previous reports of this condition have been limited to case reports or very small families. Recently, Peters et al. reported on linkage of five families of Western European descent to a 5.3 cM region on chromosome 1q21-22 between the flanking markers D1S305 and D1S1600 [Peters et al., 1998: Nat Genet 18:292-295]. We performed linkage and haplotype analysis using highly polymorphic, microsatellite markers on a large, multigeneration Caucasian kindred of German ancestry. The maximum two-point lod score achieved was 4.96 at theta(max) = 0 for marker D1S2721. Multipoint analysis gave an overall maximum lod score of 6.27 near marker D1S2721. The results of the haplotype analysis support the minimal candidate region as reported by Peters et al.

Adult↗

Emotionality and self-regulation, threat appraisal, and coping in children of divorce.

A model of the effects of children's temperament (negative and positive emotionality, impulsivity and attention focusing) on post-divorce threat appraisals, coping (active and avoidant), and psychological symptoms (depression and conduct problems) was investigated. The study utilized a sample of 223 mothers and children (ages 9 to 12 years) who had experienced divorce within the last two years. Evidence was found of direct effects of child-report negative emotionality on children's threat perceptions and of child-report positive emotionality and impulsivity on children's coping. Indirect effects of negative emotionality on active and avoidant coping through threat appraisal were found. Direct effects of the temperament variables on symptoms were also found. Cross group analyses indicated that the models were robust to age differences, but gender differences were found in the relation between negative emotionality and depression. The results of this study indicate that temperament and threat appraisals are important predictors of children's post-divorce symptoms, and that temperament is a predictor of children's appraisal and coping process.

Adaptation, Psychological↗

Potassium supplementation induces beneficial cardiovascular changes during rest and stress in salt sensitive individuals.

The typical American diet includes high salt and low potassium, a pattern linked to elevated blood pressure (BP) in cross-cultural studies. This study compared resting and stress cardiovascular responses on a high salt, low potassium diet to those observed during 2 interventions: salt restriction and potassium supplementation. Forty-seven percent of the primarily normotensive sample (n = 67 adults) were salt sensitive, showing a decrease in mean arterial pressure > or = 5 mmHg during low salt and equivalent reductions during high potassium. The equivalent benefits of the interventions were maintained, but not enhanced, during exposure to behavioral stress (i.e., no effect on reactivity). Salt resistants (SRs) exhibited no change in resting or stress BP across the diets. High salt increased cardiac index in both groups, whereas vascular tone was decreased only in the SR group. High potassium produced hemodynamic benefits similar to low salt, even with continued high salt intake.

Adult↗

High stress responsivity predicts later blood pressure only in combination with positive family history and high life stress.

High cardiovascular responsivity to stressors has not consistently improved prediction of later blood pressure increases beyond the predictive effects of baseline pressure. Animal models suggest that genetic susceptibility to hypertension and frequent stress exposure are important modulating factors in stress-related hypertension. Thus in 103 men originally tested at age 18 to 22 years and reassessed 10 years later, interactive effects of genetic susceptibility (defined as 1 or more hypertensive parents) with high stress responsivity (defined as top 25% on the basis of blood pressure and cardiac responses during both reaction time and cold pressor tasks) were examined in relation to follow-up systolic and diastolic levels and to change in blood pressure status from normal (diastolic<80 mm Hg) to marginally elevated (diastolic 85 to 95 mm Hg). Men with the combination of high stress response and hypertensive parents demonstrated higher systolic (P<0.05) and diastolic levels (P<0.05) at follow-up, and they showed a 7-fold increase (7.5, 95% confidence intervals 2.3, 24.3; P<0.001) in relative risk of change in blood pressure status versus men with no family history and a 3-fold increase (3.8, confidence intervals 1.5, 9.6; P<0.004) versus less stress-responsive men who also had hypertensive parents. In 65 men who also provided ratings of daily stress, family historyxstress responsivityxdaily stress interactions were significant in predicting follow-up systolic and diastolic levels (P<0.006 and 0.03, respectively), with highest pressure levels seen when high life stress was reported by high stress responders and/or men with hypertensive parents. In conclusion, results suggest that stress responsivity as a long-term predictor is modulated by both genetic and environmental factors.

Adult↗

Methodological issues in evaluating Rorschach validity: a comment on Burns and Viglione (1996), Weiner (1996), and Ganellen (1996)

The old controversy regarding the Rorschach Inkblot Test has recently revived. The present article suggests that the debate will be most productive if careful attention is paid to methodological issues. Three recent examples illustrate how incorrect conclusions regarding Rorschach validity may occur if methodological issues are not evaluated carefully. The present article examines (a) Burns and Viglione s (1996) conclusion that the Rorschach Human Experience Variable (HEV) is a predictor of interpersonal relatedness among adults; (b) Weiner s (1996) conclusion that the D score and Morbid Responses (MOR) are valid measures of experienced distress in Posttraumatic Stress Disorder (PTSD); and (c) Ganellen s (1996a, 1996b) conclusion that the Rorschach Depression Index (DEPI) and the Minnesota Multiphasic Personality Inventory (MMPI) are comparable in their power to identify diagnoses of depression.

Adult↗

Magnetic resonance imaging abnormalities and cognitive deficits in systemic lupus erythematosus patients without overt central nervous system disease.

OBJECTIVE: To investigate cerebral magnetic resonance imaging (MRI) abnormalities in relation to cognitive functioning in systemic lupus erythematosus (SLE) patients without a history of central nervous system (CNS) disease. METHODS: Ventricle-to-brain ratios (VBRs) and the total number of white matter hyperintensities (WMHIs) were computed in 20 female patients with non-CNS SLE using established MRI computer-generated quantification procedures. Comprehensive neuropsychological test scores across 8 domains were also obtained. RESULTS: A mean VBR of 2.83% (SD = 0.7) occurred in the non-CNS SLE patients compared with a VBR of 1.36% in a normative sample. The average number of WMHIs was 4.95 (SD = 6.0). Using a combined rating scale (VBR > 2.25%, WMHIs > 5), 7 of 20 MRI scans (35%) were classified as abnormal. Increased VBRs and larger numbers of WMHIs showed a trend association with longer duration of SLE. Thirty-five percent of the non-CNS SLE patients demonstrated neuropsychological deficits. No significant correlations were found between the VBR, total WMHIs, and cognitive scores. Comparisons of cognitively impaired and nonimpaired patients with non-CNS SLE revealed no significant differences across clinical characteristics or MRI values. CONCLUSION: Quantified MRI analyses indicated atypical brain structure and an increased number of WMHIs in a subset of non-CNS SLE patients. However, these MRI abnormalities were not associated with functional abnormalities determined by comprehensive neuropsychological testing. Therefore, MRI analyses are not likely to provide additional clinical information on cognitively impaired SLE patients who have no other evidence of CNS involvement.

Adult↗

Postexercise vasodilatation reduces diastolic blood pressure responses to stress.

Regular physical exercise is known to reduce cardiovascular risk. We examined the effects of a single bout of moderate bicycle exercise on hemodynamic measures at rest and in response to the foot cold pressor (CP) and mental arithmetic (MA). Sedentary males and females (N = 32) were tested twice, following 20 minutes of moderate exercise (exercise day) versus 20 minutes of quiet rest (control day). Although resting blood pressure was no lower 20 minutes after exercise relative to the same time point on the control day, diastolic blood pressure responses to CP (p = .05) and MA (p = .06) were attenuated on the exercise day. Furthermore, recovery from moderate exercise versus control rest was also associated with reduced vascular resistance index (VRI) at rest and during exposure to both stressors (p's < or = .02). VRI reductions were largest in subjects with elevated vascular tone on the control day and were accompanied by increases in heart rate throughout the postexercise period (p's < or = .004) and higher cardiac index during exercise recovery and in response to CP (p's < or = .05). Thus, the cardiovascular benefit of exercise may in part be due to reduced VRI and attenuated cardiovascular responses to stress during the acute postexercise period.

Adult↗

Moderators of self-other agreement: reconsidering temporal stability in personality.

Accurate prediction requires information not only about central tendencies but also about variability. In personality prediction, however, most research has focused on trait-level central tendencies. Previously proposed moderators of personality prediction are all conceptually similar in comparing an individual's central tendency in response patterns with that of the normative person. This article proposes an alternative: Trait-level prediction is enhanced by measuring the temporal stability of response patterns within persons. Across 2 studies, individuals with temporally stable response patterns had higher self-other agreement on conscientiousness and extraversion than did individuals with less temporally stable patterns. By comparison, normatively based variables (interitem variability, scalability, or construct similarity) did not moderate self-other agreement. The implications for personality structure, assessment, and prediction are discussed.

Adult↗

Temperament as a predictor of symptomatology in children: addressing contamination of measures.

Temperament has been conceptualized as an important predictor of children's psychological adjustment. However, even with reliable and valid measures, there is the additional problem of overlapping item content across measures of temperament and symptoms that threatens the interpretability of such associations. This study assessed this possible confounding using both confirmatory factor analysis (CFA) and expert ratings. A number of items from temperament measures of negative and positive emotionality, impulsivity, and attention focusing were shown to overlap with items measuring depressive and conduct problem symptoms. CFAs demonstrated that temperament could be reliably measured after eliminating overlapping items. Negative emotionality and impulsivity showed a positive relation to symptom measures, whereas positive emotionality and attention showed a negative relation to symptom measures. The pattern of associations indicated consistent relations between negative emotionality and depression and between impulsivity and conduct problems. The results show that even after removal of the threat to validity presented by overlap in measures, there continue to be significant, interpretable relations between temperament and symptoms.

Affect↗

Confirmation of a second locus for CMT2 and evidence for additional genetic heterogeneity.

The Charcot-Marie-Tooth (CMT) neuropathies are a group of disorders exhibiting neurophysical, pathological and genetic heterogeneity. CMT2 is a diagnostic subtype of this group of disorders characterized by variable expression and age-of-onset and normal or slightly diminished nerve conduction velocities. Previously, linkage and heterogeneity had been reported in CMT2 with linked families localizing to chromosome 1p (CMT2A). Recently a second CMT2 locus has been described on chromosome 7 in a single large CMT2 family (CMT2D). We have performed pedigree linkage analysis on 15 CMT2 families (N = 371 individuals, 106 affected family members) and have confirmed linkage to chromosome 7. Furthermore, using both admixture and multipoint linkage analysis we show conclusive evidence for additional heterogeneity within this clinical subtype with evidence of families that exclude linkage to both the CMT2D and CMT2A regions. In addition, unlike the previous report we found no obvious consistent clinical differences between the linked family types.

Charcot-Marie-Tooth Disease↗

Methotrexate hepatotoxicity.

Hepatoxicity is a major adverse reaction that can occur during methotrexate treatment of the rheumatic diseases. The pathologic lesions are nonspecific and the pathogenesis is poorly understood. Early studies in psoriasis clearly established a relationship between hepatic injury and several risk factors, particularly alcohol use. Methotrexate hepatoxicity occurs less frequently in rheumatoid arthritis than previously reported in psoriasis patients. Consequently, the American College of Rheumatology guidelines for methotrexate monitoring do not recommend baseline and surveillance liver biopsies in low-risk patients. These guidelines seem to be useful and cost-effective.

Antirheumatic Agents↗

Young women's condom use: the influence of acceptance of sexuality, control over the sexual encounter, and perceived susceptibility to common STDs.

A comprehensive model of the determinants of condom use among young women was developed, tested, and replicated, with longitudinal follow-up to assess predictive utility of the model for condom use over time. Participants in Study 1 and Study 2 were 198 female undergraduates (mean age, 18.6 years) and 238 female undergraduates (mean age, 19.1 years), respectively. Acceptance of sexuality and control over the sexual encounter were related to a multidimensional measure of condom use self-efficacy, which predicted condom use intentions. Perceived susceptibility to STDs was both directly related to intentions and indirectly related through perceived benefits and attitudes about condom use. Intentions predicted subsequent reports of condom use. The model suggests foci for condom use interventions for young women.

Adolescent↗

Introduction: personality psychology and the case study.

This article introduces the Journal of Personality's special issue on the life voyage of Dodge Morgan who, in 1986 at the age of 54, sailed solo around the world in 150 days. Before the voyage, Morgan agreed to participate in an intensive psychological case study, the data for which provide the focus for this special issue. William Nasby and Nancy W. Read have organized the vast array of psychological data obtained from Morgan and produced a complex and illuminating interpretation of his life, drawing liberally from the five-factor trait model of personality and the life-story model of adult identity. This introduction provides a historical and intellectual context for Nasby and Read's study by considering the various ways in which personality psychologists have employed the case study in research and examining the many conceptual and methodological problems and possibilities that arise in the psychological study of the single case.

History, 19th Century↗

Ten-year stability of cardiovascular responses to laboratory stressors.

In this study, we examined test-retest stability of cardiovascular stress responses over a decade of the life span. Participants were 55 male college undergraduates, 19 years of age at initial testing, and 29 years of age at follow-up testing. Stressors were a foot cold pressor and an aversive reaction time task. Cardiovascular measures included systolic and diastolic blood pressure, heart rate, and preejection period. For cold pressor, the magnitude and pattern of cardiovascular responses remained unchanged at the 10-year follow-up. For the reaction time task, the characteristic cardiovascular response patterns was preserved but with significant attenuation of magnitude. The present findings are consistent with previous observations of temporal stability but over a substantially longer test-retest interval. The long-term stability of stress responses is discussed in the context of stress test methodology, behavioral response demands, and maturation of the physiological systems involved in cardiovascular response expression.

Adolescent↗

The effect of methotrexate on mouse bone cells in culture.

OBJECTIVE: We have recently shown that administration of long-term, low-dose methotrexate (MTX) causes severe osteopenia in female rats. This osteopenia is characterized both by decreased osteoblast function without a decrease in osteoblast numbers, and by increased bone resorption that is believed to represent a physiologic remodeling response by osteoclasts. The present study investigates the effects of varying doses of MTX on mouse bone cells in culture. METHODS: Cells were obtained by sequential digestion of neonatal mouse calvariae, and cultured with fetal calf serum (10% for osteoblast-like cells and 2% for osteoclast-like cells). After 1 week, MTX was added to each culture in concentrations of 0.6 microM, 0.4 microM, 0.2 microM, 0.1 microM, 1 nM, and 0.5 nM. All experiments were done on 24 wells for each MTX concentration and for the controls. The effect on osteoblastic cells was assessed, at 7 days, by cell counts and by measurement of lysate alkaline phosphatase and supernatant osteocalcin levels, and, at 21 days, by analysis of the calcified matrix production, which was cultured with ascorbic acid and beta-glycerophosphate. For osteoclastic cells, cell count and lysate acid phosphatase levels were determined. RESULTS: Levels of osteoblastic cells and lysate alkaline phosphatase were not changed by any of the concentrations of MTX. Matrix calcification and supernatant osteocalcin levels were diminished by MTX in a dose-responsive manner. Osteoclast-like cell numbers and acid phosphatase levels were not significantly affected by MTX. CONCLUSION: These results suggest that diminished mouse osteoblastic cell function occurs with very low mean concentrations of MTX, in a dose-responsive manner. The mechanism seems to be inability of the cell to synthesize and calcify matrix, possibly through defective osteocalcin production. Thus, low-dose MTX may have an important impact on bone density by slowing osteoblastic matrix production.

Acid Phosphatase↗

Analysis of cognitive and psychological deficits in systemic lupus erythematosus patients without overt central nervous system disease.

OBJECTIVE: To examine cognitive and psychological functioning in relation to antiribosomal P protein autoantibodies in patients with systemic lupus erythematosus (SLE) who had no previous history of central nervous system disease (non-CNS SLE). METHODS: Comprehensive neuropsychological and psychological tests were administered to 51 non-CNS SLE patients, 29 rheumatoid arthritis (RA) patients, and 27 healthy controls. RESULTS: Twenty-nine percent of the non-CNS SLE patients, 31% of the RA patients, and 11% of the control subjects were classified as cognitively impaired. Similar reductions in intelligence, attention, and fluency were detected in the non-CNS SLE and RA patients compared with controls. The non-CNS SLE patients showed a distinct deficit in learning compared with the RA and control groups. Forty-two percent of the non-CNS SLE patients demonstrated psychological distress, compared with 7% of the RA patients and 6% of the controls. In the patient groups, neither cognitive dysfunction nor psychological distress was associated with disease activity or prednisone dosage. Elevated serum levels of autoantibodies to ribosomal P protein were not associated with either psychological or cognitive abnormalities. CONCLUSION: These results suggest that certain cognitive deficits in non-CNS SLE patients may not be specific to the immunopathology of SLE. In contrast, it is possible that deficits in learning, as well as psychological distress without major psychiatric pathology, may be subtle manifestations of CNS lupus.

Adult↗