Large-scale study of the precision of the approximate number system: Differences between formats, heterogeneity and congruency effects.

The study used a large sample of elementary schoolchildren in Russia (N = 3,448, 51.6% were girls, with a mean age of 8.70 years, ranging 6-11 years) to investigate the congruency, format and heterogeneity effects in a nonsymbolic comparison test and between-individual differences in these effects with generalized linear mixed effects models (GLMMs). The participants were asked to compare two arrays of figures of different colours in spatially separated or spatially intermixed formats. In addition, the figures could be similar or different for the two arrays. The results revealed that congruency (difference between congruent and incongruent items), format (difference between mixed and separated formats) and heterogeneity (difference between homogeneous and heterogeneous conditions) interacted. The heterogeneity effect was higher in the separated format, while the format effect was higher for the homogeneous condition. The separated format produced a greater congruency effect than the mixed format. In addition, the congruency effect was lower in the heterogeneous condition than in the homogeneous condition. Analysis of between-individual differences revealed that there was significant between-individual variance in the format and congruency effects. Analysis of between-grade differences revealed that accuracy improved from grade 1 to grade 4 only for congruent trials in separated formats. Consequently, the congruency effect increased in separated/homogeneous and separated/heterogeneous conditions. In general, the study demonstrated that the test format and heterogeneity affected accuracy and that this effect varied for congruent and incongruent items.

Technetium-99m methoxyisobutylisonitrile scintimammography for monitoring and early prediction of breast cancer response to neoadjuvant chemotherapy.

PURPOSE: The aim of the study was to evaluate the clinical value of scintimammography (SMG) with technetium-99m methoxyisobutylisonitrile (Tc-MIBI) for evaluating the efficacy of neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS: A total of 65 patients with advanced breast cancer (BC) were included in the study. Planar SMG with 740 MBq of Tc-MIBI was performed before the start and after two to three and four to six cycles of NAC. NAC efficacy was estimated as progression (grade I), stabilization (grade II), partial effect (grade III), prominent efficacy (grade IV), and complete response (grade V). In 59 women, histopathologic verification of BC response to NAC was performed according to the Miller-Payne classification with the same scores as were used in the evaluation of scintigraphic response. RESULTS: After two to three cycles of NAC, disease progression was detected in five of 65 (7.7%) patients. In 27 (41.5%) patients SMG detected early stabilization of BC. Only one of these patients achieved prominent (grade IV) response after the end of NAC. Partial (grade III) response after two to three cycles of NAC was seen in 24 (36.9%) patients. One-third of them had grades IV-V response at the end of treatment. The most promising was the group of nine (13.8%) patients with early-grades IV-V response, all of which transformed to complete response at the end of NAC. As per histopathologic verification, early SMG had 85.7% sensitivity, 94.2% specificity, and 93.2% accuracy in predicting complete pathologic response to four to six cycles of NAC. CONCLUSION: After two to three cycles of NAC, SMG with Tc-MIBI can determine patients with low, intermediate, and high probability of complete response to five to six cycles of NAC Video Abstract: http://links.lww.com/NMC/A43.

MLVA and SNP analysis identified a unique genetic cluster in Bulgarian Bacillus anthracis strains.

A collection of 40 Bacillus anthracis strains mostly isolated from soil in Bulgaria between 1960 and 1980 were investigated. All strains were proven to be B. anthracis by culture and amplification of a B. anthracis-specific chromosomal marker. PCR demonstrated that in nine strains both virulence plasmids (pX01+/pX02+) and in four strains only one plasmid (pX02+) were present, whereas the majority of strains (n = 27) lacked both plasmids (pX01-/pX02-). Multi-locus-variable number of tandem repeat-analysis (MLVA) using 15 markers differentiated three genotypes. Comparison with typing data of more than 1,000 different B. anthracis strains revealed that Bulgarian genotypes affiliated with the A1.a cluster and form their own unique cluster different from clusters containing strains isolated in geographical proximity, e.g., Turkey, Georgia, Hungary, Albania or Italy. In addition, a new allele of one marker (vrrC2) was identified. Canonical single nucleotide polymorphisms analysis allocated 31 Bulgarian strains into the A.Br.008/009 and nine strains into the A.Br.WNA group, which is the first description of B. anthracis strains of the A.Br.WNA group on the Eurasian continent.