A comparison of the Allen Cognitive Level Test and the Wisconsin Card Sorting Test in adults with schizophrenia.

OBJECTIVE: This study examines the relationship among executive function, visuospatial problem solving, and measures of occupational functioning in 33 adult men with schizophrenia or schizoaffective disorder. METHOD: Three measures were administered in a one-time assessment session. The Wisconsin Card Sorting Test (WCST) was used to measure executive functioning, abstract reasoning, and problem-solving abilities. The Allen Cognitive Level (ACL) Test was used to measure learning, problem solving, and visuospatial abilities. The Routine Task Inventory (RTI) measured the level of performance in activities of daily living. RESULTS: Using multiple regression controlling for age, the WCST significantly predicted performance on the ACL the RTI. Perseverative errors on the WCST were negatively correlated with the ACL (r = -.47) and RTI scores (r = -.59). The ACL and RTI were also significantly correlated (r = .67). CONCLUSION: Both the WCST and the ACL are sensitive to similar domains of functioning and are predictive of task performance. The results support the use of the ACL as a quick measure of a person's cognitive and functional abilities.

Pathogen-specific loss of host resistance in mice lacking the IFN-gamma-inducible gene IGTP.

Interferon-gamma (IFN-gamma) is critical for defense against pathogens, but the molecules that mediate its antimicrobial responses are largely unknown. IGTP is the prototype for a family of IFN-gamma-regulated genes that encode 48-kDa GTP-binding proteins that localize to the endoplasmic reticulum. We have generated IGTP-deficient mice and found that, despite normal immune cell development and normal clearance of Listeria monocytogenes and cytomegalovirus infections, the mice displayed a profound loss of host resistance to acute infections of the protozoan parasite Toxoplasma gondii. By contrast, IFN-gamma receptor-deficient mice have increased susceptibility to all three pathogens. Thus, IGTP defines an IFN-gamma-regulated pathway with a specialized role in antimicrobial resistance.

Coupled site-directed mutagenesis/transgenesis identifies important functional domains of the mouse agouti protein.

The agouti locus encodes a novel paracrine signaling molecule containing a signal sequence, an N-linked glycosylation site, a central lysine-rich basic domain, and a C-terminal tail containing 10 cysteine (Cys) residues capable of forming five disulfide bonds. When overexpressed, agouti causes a number of pleiotropic effects including yellow coat and adult-onset obesity. Numerous studies suggest that agouti causes yellow coat color by antagonizing the binding of alpha-melanocyte-stimulating hormone (alpha-MSH) to the alpha-MSH-(Melanocortin-1) receptor. With the goal of identifying functional domains of agouti important for its diverse biological activities, we have generated 14 agouti mutations by in vitro site-directed mutagenesis and analyzed these mutations in transgenic mice for their effects on coat color and obesity. These studies demonstrate that the signal sequence, the N-linked glycosylation site, and the C-terminal Cys residues are important for full biological activity, while at least a portion of the lysine-rich basic domain is dispensable for normal function. They also show that the same functional domains of agouti important to coat color determination are important for inducing obesity, consistent with the hypothesis that agouti induces obesity by antagonizing melanocortin binding to other melanocortin receptors.