Faculty Bibliography

Although it is common for patients with dissociative disorders to report a history of suicide attempts, there is very little data systematically comparing suicidality in patients with dissociative disorders versus patients without these disorders. The subjects in our study were 231 patients consecutively admitted to an inner-city, hospital-based outpatient psychiatric clinic. Eighty-two of these patients completed structured interviews for dissociative disorders, borderline personality disorder, and trauma history (dissociative disorders interview schedule) and for posttraumatic stress disorder and substance abuse (Structured Clinical Interview for DSM-IV). Patients receiving a dissociative disorder diagnosis were compared with nondissociative patients on measures of self-harm and suicidality. Presence of a dissociative disorder was strongly associated with all measures of self-harm and suicidality. When we focused on patients with a history of multiple suicide attempts, significant associations were found between several diagnoses (dissociative disorder; borderline personality disorder; posttraumatic stress disorder; alcohol abuse/dependence) and multiple suicide attempter status. When these diagnoses were entered in a logistic regression, a highly significant association remained for dissociative diagnosis and multiple suicide attempter status (odds ratio, 15.09; 95% confidence interval, 2.67-85.32; p = 0.002). Dissociative disorders are commonly overlooked in studies of suicidality, but in this population they were the strongest predictor of multiple suicide attempter status

Elevated platelet serotonin (5-hydroxytryptamine, 5-HT) is found in a subset of children with autism and in some of their first-degree relatives. Indices of the platelet serotonin system, including whole blood 5-HT, 5-HT binding affinity for the serotonin transporter (K(m)), 5-HT uptake (V(max)), and lysergic acid diethylamide (LSD) receptor binding, were previously studied in 24 first-degree relatives of probands with autism, half of whom were selected for elevated whole blood 5-HT levels. All subjects were then genotyped for selected polymorphisms at the SLC6A4, HTR7, HTR2A, ITGB3, and TPH1 loci. Previous studies allowed an a priori prediction of SLC6A4 haplotypes that separated the subjects into three groups that showed significantly different 5-HT binding affinity (K(m), p=0.005) and 5-HT uptake rate (V(max), p=0.046). Genotypes at four individual polymorphisms in SLC6A4 were not associated with platelet 5-HT indices. Haplotypes at SLC6A4 and individual genotypes of polymorphisms at SLC6A4, HTR7, HTR2A, ITGB3, and TPH1 showed no significant association with whole blood 5-HT. Haplotype analysis of two polymorphisms in TPH1 revealed a nominally significant association with whole blood 5-HT (p=0.046). These initial studies of indices of the 5-HT system with several single-nucleotide polymorphisms at loci in this system generate hypotheses for testing in other samples

Considerable evidence suggests that estrogen can have neuroprotective effects. However, recent results raised important questions regarding the conditions under which hormone therapy (HT) following menopause can be beneficial. It has been suggested that variables such as time of initiation and duration of HT use are of critical importance for beneficial cognitive effects to be observed. The aim of the present study was to investigate the potential neuroprotective effects of estrogens in aging on brain regions with high levels of estrogen receptors, namely the hippocampus (HC) and the amygdala (AG). In order to better characterize the punctual and long-term effects of estrogens, we tested postmenopausal women currently using estrogen therapy alone (ET), past HT users, never users, and men. Age at menses, age at menopause, HT duration and age were included as covariates in the analysis. Results demonstrate that women using ET had larger left and right HC volumes compared to men, and larger right HC volumes compared to past users and never users. Importantly, we found a significant negative relationship between ET duration and HC volume in this group. The observed effects were region-specific since no significant differences could be observed for the AG. In summary, these findings support a treatment duration dependent neuroprotective role of estrogen on HC volume in aging

Establishing optimal correspondence across object populations is essential to statistical shape analysis. Minimizing the description length (MDL) is a popular method for finding correspondence. In this work, we extend the MDL method by incorporating various local curvature metrics. Using local curvature can improve performance by ensuring that corresponding points exhibit similar local geometric characteristics that can't always be captured by mere point locations. We illustrate results on a variety of anatomical structures. The MDL method with a combination of point locations and curvature outperforms all the other methods we analyzed, including traditional MDL and spherical harmonics (SPHARM) correspondence, when the analyzed object population exhibits complex structure. When the objects are of simple nature, however, there's no added benefit to using the local curvature. In our experiments, we did not observe a significant difference in the correspondence quality when different curvature metrics (e.g. principal curvatures, mean curvature, Gaussian curvature) were used.