Neuroimaging-based classification of PTSD using data-driven computational approaches: a multisite big data study from the ENIGMA-PGC PTSD consortium

Background: Recent advances in data-driven computational approaches have been helpful in devising tools to objectively diagnose psychiatric disorders. However, current machine learning studies limited to small homogeneous samples, different methodologies, and different imaging collection protocols, limit the ability to directly compare and generalize their results. Here we aimed to classify individuals with PTSD versus controls and assess the generalizability using a large heterogeneous brain datasets from the ENIGMA-PGC PTSD Working group. Methods: We analyzed brain MRI data from 3,477 structural-MRI; 2,495 resting state-fMRI; and 1,952 diffusion-MRI. First, we identified the brain features that best distinguish individuals with PTSD from controls using traditional machine learning methods. Second, we assessed the utility of the denoising variational autoencoder (DVAE) and evaluated its classification performance. Third, we assessed the generalizability and reproducibility of both models using leave-one-site-out cross-validation procedure for each modality. Results: We found lower performance in classifying PTSD vs. controls with data from over 20 sites (60 % test AUC for s-MRI, 59 % for rs-fMRI and 56 % for D-MRI), as compared to other studies run on single-site data. The performance increased when classifying PTSD from HC without trauma history in each modality (75 % AUC). The classification performance remained intact when applying the DVAE framework, which reduced the number of features. Finally, we found that the DVAE framework achieved better generalization to unseen datasets compared with the traditional machine learning frameworks, albeit performance was slightly above chance. Conclusion: These results have the potential to provide a baseline classification performance for PTSD when using large scale neuroimaging datasets. Our findings show that the control group used can heavily affect classification performance. The DVAE framework provided better generalizability for the multi-site data. This may be more significant in clinical practice since the neuroimaging-based diagnostic DVAE classification models are much less site-specific, rendering them more generalizable.Stress-related psychiatric disorders across the life spa

Failure of chemoprophylaxis with standard antituberculosis agents in child contacts of multidrug-resistant tuberculosis cases

BACKGROUND: There is little published information on optimal chemoprophylaxis for children with multidrug-resistant tuberculosis (MDR-TB) contacts. Current guidelines of World Health Organization suggest that isoniazid (INH), the standard first-line chemoprophylaxis, be used for those exposed to MDR-TB. METHODS: This is a retrospective review of medical records of 5 children residing in the Western Cape Province, South Africa, who developed MDR-TB while receiving conventional chemoprophylaxis with either INH or a combination of INH, rifampin, and pyrazinamide. RESULTS: Adult MDR-TB source cases were identified for all children and resistance patterns of patient and source case isolates matched in all cases. The median age of the patients was 0.4 years. One patient participated in a trial of INH chemoprophylaxis for HIV-infected children. Four HIV-uninfected infants presented with TB-related symptoms several months after being given chemoprophylaxis because of a known source case. Stigmata of TB were cough >3 weeks in 4, weight loss or a history of failing to thrive in 3, fever in 2 infants, and reported night sweats in 1. Chest radiographs at diagnosis revealed lymphadenopathy, lobar opacification, and airway narrowing. All patients were treated for varying time periods at a TB referral institution in the Western Cape. CONCLUSIONS: Standard, first-line anti-TB agents were inadequate to prevent MDR-TB in children exposed to MDR-TB contacts. Second-line chemoprophylaxis, reflecting the susceptibility profile of the source case's isolate, with at least 2 drugs with activity against the drug-resistant isolate for 6-12 months should be considered. © 2007 Lippincott Williams & Wilkins, Inc.Articl

Topographic differences in amniotic fluid concentrations of prostanoids in women in spontaneous labor at term

These studies were designated to determine if there are differences in prostanoid concentrations between amniotic fluid (AF) retrieved transvaginally from the membrane forebag (lower or forebag compartment) and fluid retrieved by transabdominal amniocentesis from the 'upper compartment' in women in labor. Fluid was retrieved from 53 women in active labor who underwent transabdominal and transvaginal amniocentesis. Fluid was assayed for prostaglandin E(2) (PGE(2)) and prostaglandin F-2 alpha (PGF(2 alpha)), 13,14-dihydro-15-keto-prostaglandin F-2 alpha (PGFM), thromboxane B-2 (TXB(2)), and 6-keto-prostaglandin F-1 alpha (6-k-PGF(1 alpha)) using sensitive and specific radioimmunoassays. Concentrations of all prostanoids measured were significantly higher in fluid retrieved by transvaginal than transabdominal amniocentesis; the magnitude of the increase (measured as the ratio of concentrations in the lower/upper compartment) was higher for PGF(2 alpha) and TXB(2) than for the other prostanoids measured; for each prostanoid measured, there was a significant correlation between the concentration in the upper and lower compartment

Interleukin-1 receptor antagonist (IL-1ra) production by human amnion, chorion, and decidua

PROBLEM: This study was conducted to determine whether (1) conditioned media from unstimulated primary cultures of human amnion, chorion, or decidua contain detectable concentrations of IL-1ra in vitro, and (2) bacterial endotoxin (LPS), tumor necrosis factor-alpha ( TNF-alpha), or IL-1-beta (IL-1beta) stimulate amnion, chorion, or decidua to produce increased amounts of IL-1ra

Colored Emission of Rare Earth Ions in a Potassium Feldspar Glass

The viability of rare earth ions as fluorescent coloring additives for dental porcelain was investigated. The data presented allow the formulation of porcelain with specific color properties under illumination by ultraviolet light. Attention is drawn to the possibility of energy transfer occurring with the result that prediction of color may not be done by application of the additive color-mixing scheme.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67486/2/10.1177_00220345770560110401.pd