Publications by Year: 2005

Studies of the five-factor model of personality in schizotypal personality disorder (SPD) have produced inconsistent results, particularly with respect to openness. In the present study, the NEO-FFI was used to measure five-factor personality dimensions in 28 community volunteers with SPD and 24 psychiatrically healthy individuals. Standard multivariate statistical analyses were used to evaluate personality differences as a function of diagnosis and gender. Individuals with SPD had significantly higher levels of neuroticism and significantly lower levels of extraversion, agreeableness and conscientiousness than those without SPD. Female, but not male, SPD subjects had significantly higher openness levels than their healthy counterparts, and this gender-specific group difference persisted when SPD symptom severity was statistically controlled. These findings suggest that gender-associated differences in openness may account for prior inconsistent findings regarding this dimension, and they further underscore the importance of examining gender effects in future studies of SPD.

The reaction of [Cp2*Rh2Cl4] (Cp* = C5Me5) with a slight excess of K(3)SbS(3) in boiling THF gave the neutral clusters [Cp*4Rh4S5] (1), [Cp*3Rh3Sb2S5] (2), and after salt metathesis [Cp*3Rh3SbSn]PF6 (3; n = 5 and 6). The structures of 1-3 are heterocubane clusters with CpRh, S, and Sb vertices but with sulfur inserted into one (1 and 2) or two (3) edges. X-ray diffraction analysis of 2 additionally reveals a very short Sb-S distance of 2.297(1) A within the novel mu3-Sb2S4 ligand. Density functional theory calculation of the model compounds [SSbS]3-, [HSSbS]2-, and [HSSbH2S]0 provided strong evidence for the existence of a stable terminal Sb=S double bond in 2.

INTRODUCTION: Schizotypal personality disorder (SPD) shares with schizophrenia many biological features, yet little is known about the clinical characteristics of persons diagnosed with this disorder. This report describes the clinical, cognitive and socio-occupational characteristics of a community sample of subjects diagnosed with SPD. METHOD: Sixty-four male and 40 female neuroleptic-naive DSM-IV SPD subjects and 59 male and 51 female comparison subjects were recruited from the community for a total sample of 214 subjects. Demographic and cognitive differences between groups and, within the SPD group, the effect of gender on clinical features, such as the SPD criteria, SAPS, SANS, Schizotypal Personality Questionnaire, and co-morbidity, were examined using ANOVA and Chi-square distributions. RESULTS: SPD subjects, in contrast to comparison subjects, had significantly lower socio-economic status, poorer social relationships and skills, and lower vocabulary scores. Furthermore, SPD subjects demonstrated more impairment on Vocabulary scores than on Block Design, as measured by the WAIS-R, a pattern not seen in comparison subjects. In the SPD cohort, positive symptoms predominated and nearly half were co-morbid for major depression. With respect to gender, male SPD subjects, compared with female SPD subjects, evinced significantly more negative symptoms, fewer friends, had more odd speech, and were more likely to also suffer from paranoid and narcissistic personality disorders. In contrast to male SPD subjects, female SPD subjects perceived themselves to be more disorganized. CONCLUSIONS: SPD subjects, similar to schizophrenics, are impaired socially, occupationally, and cognitively, particularly in the area of verbal measures. Moreover, male SPD subjects may be more severely affected than female SPD subjects across multiple domains of functioning.

BACKGROUND: The visual combination of different modalities is essential for many medical imaging applications in the field of Computer-Assisted medical Diagnosis (CAD) to enhance the clinical information content. Clinically, incontinence is a diagnosis with high clinical prevalence and morbidity rate. The search for a method to identify risk patients and to control the success of operations is still a challenging task. The conjunction of magnetic resonance (MR) and 3D ultrasound (US) image data sets could lead to a new clinical visual representation of the morphology as we show with corresponding data sets of the female anal canal with this paper. METHODS: We present a feasibility study for a non-rigid registration technique based on a biomechanical model for MR and US image data sets of the female anal canal as a base for a new innovative clinical visual representation. RESULTS: It is shown in this case study that the internal and external sphincter region could be registered elastically and the registration partially corrects the compression induced by the ultrasound transducer, so the MR data set showing the native anatomy is used as a frame for the US data set showing the same region with higher resolution but distorted by the transducer CONCLUSION: The morphology is of special interest in the assessment of anal incontinence and the non-rigid registration of normal clinical MR and US image data sets is a new field of the adaptation of this method incorporating the advantages of both technologies.

OBJECTIVE: To present and evaluate a registration method to fuse complementary information of CT and MRI of the temporal bone. METHODS: CT and MRI of the temporal bone of 26 patients were independently registered 4 times. A manual, iterative, intrinsic, rigid, and retrospective registration method was used. Mean CREm (consistency registration error) was calculated as a reproducibility measurement.

OBJECTIVE: The authors examined the association between volume of the fusiform gyrus, a region involved in face processing, and the personality trait of extraversion in patients with schizophrenia.

The purpose of this study was to compare the cognitive profiles of men and women with clinically defined schizotypal personality disorder (SPD). We examined the neuropsychological profile of SPD in 26 right-handed females and 31 right-handed males who met DSM-IV criteria for SPD, and matched comparison subjects. Cognitive performance was assessed on measures of abstraction, verbal and spatial intelligence, learning and memory, language, attention, and motor skills. Neuropsychological profiles were constructed by standardizing test scores based on the means and standard deviations of comparison groups matched for sex, age, handedness, ethnicity and parental SES. Overall, SPD subjects showed mild, general decrements in performance in most cognitive domains. However, unlike male SPD subjects, female SPDs did not show relative deficits in verbal learning and abstraction. The results suggest a less severe pattern of cognitive deficits in women with SPD compared to men, consistent with hypotheses of gender differences in cognitive function in schizophrenia.

Resolved NMR spectra from samples in inhomogeneous B0 and B1 fields can be obtained with the so-called "ex situ" methodology, employing a train of composite or adiabatic z-rotation RF pulses to periodically refocus the inhomogeneous broadening during the detection of the time-domain signal. Earlier schemes relied on a linear correlation between the inhomogeneous B0 and B1 fields. Here the pulse length, bandwidth, and amplitude of the adiabatic pulses of the hyperbolic secant type are adjusted to improve the refocusing for a setup with non-linear correlation. The field correlation is measured using a two-dimensional nutation experiment augmented with a third dimension with varying RF carrier frequency accounting for off-resonance effects. The pulse optimization is performed with a computer algorithm using the experimentally determined field correlation and a standard adiabatic z-rotation pulse as a starting point for the iterative optimization procedure. The shape of the z-rotation RF pulse is manipulated to provide refocusing for the conditions given by the sample-, magnet-, and RF-coil geometry.

We present a computational framework for image-based analysis and interpretation of statistical differences in anatomical shape between populations. Applications of such analysis include understanding developmental and anatomical aspects of disorders when comparing patients versus normal controls, studying morphological changes caused by aging, or even differences in normal anatomy, for example, differences between genders. Once a quantitative description of organ shape is extracted from input images, the problem of identifying differences between the two groups can be reduced to one of the classical questions in machine learning of constructing a classifier function for assigning new examples to one of the two groups while making as few misclassifications as possible. The resulting classifier must be interpreted in terms of shape differences between the two groups back in the image domain. We demonstrate a novel approach to such interpretation that allows us to argue about the identified shape differences in anatomically meaningful terms of organ deformation. Given a classifier function in the feature space, we derive a deformation that corresponds to the differences between the two classes while ignoring shape variability within each class. Based on this approach, we present a system for statistical shape analysis using distance transforms for shape representation and the support vector machines learning algorithm for the optimal classifier estimation and demonstrate it on artificially generated data sets, as well as real medical studies.