Hemispheric asymmetries in feature integration during visual word recognition

Although the definitive source of the left hemisphere's superiority for visual word recognition remains illusive, some argue that the left (LH) and right (RH) hemispheres engage different strategies during early perceptual processes involved in stimulus encoding. In particular, it is proposed that the LH treats a word as a unitary perceptual group whereas the RH processes the letters comprising a word as a series of individual perceptual units. The present study investigated support for this processing distinction by examining hemispheric strategies for temporal integration using Prinzmetal and Millis-Wright's (1984) feature-binding paradigm. A total of 20 participants identified the colour and identity of a target letter, presented within a three-letter word (e.g., ART) or nonword (e.g., HRF), directed to their left or right visual field. Errors were classified on the basis of whether they involved substitution of a colour present within the stimulus but at a different location (ON error), or the substitution of a colour not present within the stimulus (OFF error). As anticipated, for word stimuli there was a higher proportion of OFF errors associated with trials directed to the RH, consistent with the notion that the LH treats words as single perceptual units and is hence biased toward miscombination of perceptual information present within the stimulus. The pattern of ON errors across stimulus type provided clear evidence of RH sequential encoding effects, with the number of errors increasing markedly across the ordinal position of the letters comprising the stimulus string. As such, these data provide new evidence that the LH's advantage for visual word recognition arises, at least in part, from the ability to encode verbal stimuli as single perceptual units.     

Comparison of new alcohol use test, the Helsinki Alcohol Use Test questionnaire, and Alcohol Use Disorders Identification Test and laboratory markers serum gamma-glutamyl transferase and carbohydrate-deficient transferrin

The purpose of the present study was to compare and evaluate the new Helsinki Alcohol Use Test (HAUT) and Alcohol Use Disorders Identification Test (AUDIT) as screening instrument in the general working population. The relationship between the HAUT and serum gamma-glutamyl transferase (GGT), and carbohydrate-deficient transferrin (CDT) was also evaluated. Our results seem to indicate that the HAUT has good performance as screening instrument for alcohol-related problems in the general population.     

Vesicoureteral reflux in children with suspected and proven urinary tract infection

The aim of this study was to estimate the prevalence of vesicoureteral reflux (VUR) and clinically significant ultrasonography (US) abnormalities in a large group of children with proven and suspected urinary tract infection (UTI). The medical reports on renal US and voiding cystouretrographies (VCUG) of 2,036 children were reviewed. Renal US was performed on all children and VCUG on 1,185 children (58%). Based on the urine culture data, the UTI diagnoses were classified into five reliability classes (proven, likely, unlikely, false and no microbial data). The UTI diagnose was considered proven in 583/2036 (28.6%) and false in 145 (7.1%) cases. The prevalence of VUR was similar among those with proven and false UTI [37.4 vs. 34.8%; relative risk (RR) 1.08, 95% confidence intervals (95% CI) 0.7–1.7, P = 0.75] and decreased with increasing age (P = 0.001). Clinically significant US abnormalities occurred in 87/583 (14.9%) cases with proven UTI and significantly less often (11/145, 7.6%) in the false UTI class (RR 1.96, 95% CI 1.1–3.6, P = 0.02). Our finding supports the claim that VUR is not significantly associated to UTI and that its occurrence among children even without UTI is significantly higher than traditional estimates. This challenges the recommendations of routine VCUG after UTI.     

Spontaneous mutation frequency and emergence of ciprofloxacin resistance in Campylobacter jejuni and Campylobacter coli

OBJECTIVES: We analysed the contribution of spontaneous mutation frequency to the evolution of ciprofloxacin resistance and the diversity of mutations in the quinolone resistance-determining region (QRDR) of gyrA and in the intergenic region, cmeR-cmeA, of the CmeABC efflux pump in Campylobacter jejuni and Campylobacter coli. METHODS: The mutation frequency was measured in 11 quinolone-susceptible C. jejuni and 5 C. coli strains, with and without ox bile. MICs and target-specific and efflux-associated mutations were studied for a number of colonies of each strain selected from plates containing 1 mg/L ciprofloxacin. RESULTS: The spontaneous mutation frequency level among susceptible C. jejuni and C. coli strains ranged from hypomutable (approximately 4 x 10(-9)) to strongly mutable (approximately 7 x 10(-3)). Ox bile had no effect on mutation frequency. Pre-existing ampicillin and tetracycline resistance increased the MICs of ciprofloxacin for two strains from 0.032-0.125 to 0.5 mg/L. MICs of ciprofloxacin for the colonies selected from plates containing 1 mg/L ciprofloxacin varied from 1 to 16 mg/L, with the Thr-86-->Ile or Asp-90-->Asn mutation detected in the QRDR of gyrA. In 21.5% (14/65) of the selected colonies, no specific mutations existed. Two types of mutations in CmeR promoter-binding inverted sequences were identified both in the parent strains and in the colonies selected from ciprofloxacin plates. CONCLUSIONS: The variation in mutation frequencies between most C. jejuni and C. coli strains was up to 700-fold. Mutation in the QRDR of gyrA or in the intergenic region was not associated with differences in spontaneous mutation frequencies. Previously acquired resistance to tetracycline and ampicillin predisposed strains to high-level ciprofloxacin resistance and to multiple antibiotic resistance.