Among patients with non-small-cell lung cancer who receive erlotinib, the presence of an EGFR mutation may increase responsiveness to the agent, but it is not indicative of a survival benefit.

Normative, reliability, and validity data are reported for the Mathematics Anxiety Rating Scale (MARS), a measure of mathematics anxiety for use in treatment and research. Normative data were collected on a sample of 397 college students. The instrument has high test-retest and internal consistency reliability. Evidence for validity comes from three studies in which MARS scores showed expected decreases following behavior therapy for mathematics anxiety, and a separate validity study in which MARS scores were found to correlate negatively with scores on a mathematics test. Possible uses of the instrument in treatment and research are discussed.

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Woodchucks were used to study the antiviral activity and toxicity of fialuridine (FIAU; 1,-2Јdeoxy-2Јfluoro-1-␤-Darabinofuranosyl-5-iodo-uracil). In an initial experiment, groups of six chronic woodchuck hepatitis virus (WHV) carrier woodchucks received daily doses of FIAU by intraperitoneal injection for 4 weeks. At 0.3 mg/kg/d, the antiviral effect was equivocal, but at 1.5 mg/kg/d, FIAU had significant antiviral activity. No evidence of drug toxicity was observed during the 4-week period of treatment or during posttreatment follow-up. In a second experiment, groups of nine WHV carriers or uninfected woodchucks were given 1.5 mg/kg/d of FIAU orally for 12 weeks, and the results compared with placebo-treated controls. After 4 weeks, the serum WHV-DNA concentration in the FIAUtreated carrier group was two to three logs lower than that in the placebo-treated group. After 12 weeks of FIAU treatment, serum WHV DNA was not detectable by conventional dot-blot analysis, hepatic WHV-DNA replicative intermediates (RI) had decreased 100-fold, and hepatic expression of WHV core antigen was remarkably decreased. No evidence of toxicity was observed after 4 weeks, but, after 6 to 7 weeks, food intake decreased and, after 8 weeks, the mean body weights of woodchucks treated with FIAU were significantly lower than controls. Anorexia, weight loss, muscle wasting, and lethargy became progressively severe, and all FIAU-treated woodchucks died or were euthanized 78 to 111 days after treatment began. Hepatic insufficiency (hyperbilirubinemia, decreased serum fibrinogen, elevated prothrombin time), lactic acidosis, and hepatic steatosis were characteristic findings in the final stages of FIAU toxicity in woodchucks. The syndrome of delayed toxicity in woodchucks was similar to that observed previously in humans treated with FIAU, suggesting that the woodchuck should be valuable in future investigations of the molecular mechanisms of FIAU toxicity in vivo and for preclinical toxicological evaluation of other nucleoside analogs before use in patients. (HEPATOLOGY 1998;28:179-191.)

Dideoxy chain-termination DNA sequencing was used to determine the specific DNA base changes induced after in vivo exposure of Escherichia coli to N-methyl-Nnitrosourea (MNU) and N-ethyl-N-nitrosourea (ENU) using the xanthine guanine phosphoribosyltransferase (gpt) gene as the genetic target. The resultant mutation spectra were compared with the levels of O6-alkylguanine and 04-alkylthymidine in genomic DNA immediately after exposure. All (39/39) of the MNU-induced mutations were G-C-+A-T transitions. In contrast, 24/33 point mutations isolated following ENU treatment were G-C-+AT transitions, 7/33 were A-T-*GC transitions,