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Background: The association of behavioural phenotype assessment with cytogenomic characterisation may provide a better comprehension of genotype–phenotype correlations in syndromes caused by chromosomal abnormalities, such as 18p deletion syndrome. Method: We report on four Brazilian patients with 18p deletion syndrome characterised by cytogenomic techniques and detailed neuropsychological evaluation. Intellectual, adaptive and behavioural characteristics were assessed through the Wechsler's Scales, the Vineland‐II Scale and the Child Behaviour Checklist, respectively. Socio‐economic measures including main caretaker educational level and family income as defined by Brazilian criteria for social class classification were also collected to evaluate a possible contribution of environmental factors in neurocognitive variability. Results: Two out of four patients showed intellectual disability (IQ < 70). Wechsler's scale results suggest that in our sample, interpretation of social situations based on observation of non‐verbal behaviour constitute a cognitive strength while judgement of social rules and language skills associated with word knowledge and verbal fluency may be a cognitive weakness. Concerning adaptive behaviour, motor and socialisation domains showed to better develop than communication and daily living skills on the Vineland‐II Scale. Only one patient presented internalising behavioural problems based on the Child Behaviour Checklist. Our results also suggested that socio‐economic status may contribute to overall patient development. Conclusion: Our results suggest that some 18p deletion syndrome patients may present average intellectual performance and that the segment deletion size and some families' socio‐economic conditions may influence cognitive development. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effects of an acute dose of the benzodiazepine (BZ) lorazepam in young healthy volunteers on five distinguishable visual perception abilities determined by previous factor-analytic studies. Methods This was a double-blind, cross-over design study of acute oral doses of lorazepam (2 mg) and placebo in young healthy volunteers. We focused on a set of paper-and-pencil tests of visual perceptual abilities that load on five correlated but distinguishable factors (Spatial Visualization, Spatial Relations, Perceptual Speed, Closure Speed, and Closure Flexibility). Some other tests (DSST, immediate and delayed recall of prose; measures of subjective mood alterations) were used to control for the classic BZ-induced effects. Results Lorazepam impaired performance in the DSST and delayed recall of prose, increased subjective sedation and impaired tasks of all abilities except Spatial Visualization and Closure Speed. Only impairment in Perceptual Speed (Identical Pictures task) and delayed recall of prose were not explained by sedation. Conclusion Acute administration of lorazepam, in a dose that impaired episodic memory, selectively affected different visual perceptual abilities before and after controlling for sedation. Central executive demands and sedation did not account for results, so impairment in the Identical Pictures task may be attributed to lorazepam's visual processing alterations. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

1 Nine synthetic amides similar to natural N-piperidine-3-(4,5-methylenedioxyphenyl)-2-(E)-propenamide and N-pyrrolidine-3-(4,5-methylenedyoxiphenyl)-2-(E)-propenamide were synthesized and identified by their spectroscopic data. 2 The toxicity of these synthetic amides to the Atta sexdens rubropilosa workers and the antifungal activity against Leucoagaricus gongylophorus, the symbiotic fungus of the leaf-cutting ants, were determined. 3 Workers ants that were fed daily on an artificial diet to which these compounds were added had a higher mortality rate than the controls for N-pyrrolidine-3-(3′,4′-methylenedioxyphenyl)-2-(E)-propenamide and N-benzyl-3-(3′,4′-methylenedioxyphenyl)-2-(E)-propenamide at a concentration of 100 µg/mL. 4 The completely inhibition (100%) of the fungal growth was observed with N-piperidine-3-(3′,4′-methylenedioxyphenyl)-2-(E)-propenamide and N,N-diethyl-3-(3′,4′-methylenedioxyphenyl)-2-(E)-propenamide at concentrations of 50 and 100 µg/mL and N-pirrolidine-3-(3′,4′-methylenedioxyphenyl)-2-(E)-propenamide at a concentration of 100 µg/mL. 5 The possibility of controlling these insects in the future using synthetic piperamides that can simultaneously target both organisms is discussed. [ABSTRACT FROM AUTHOR]

This study was designed to explore the effects on performance in stem-completion tasks of two benzodiazepines (BZ) in equipotent doses: lorazepam, a drug that atypically disrupts perceptual priming, and flunitrazepam, a compound with standard BZ effects. The study followed a placebo-controlled, double-blind, parallel-group design. Thirty-six young and healthy subjects carried out three completion tasks at theoretical peak-plasma concentrations of drugs: (a) indirect tasks, in which the subjects were instructed to complete stems with the first word that came to mind; (b) direct inclusion tasks/cued recall, in which the participants had to try to use words seen at study as completions; and (c) direct exclusion tasks, in which words seen at study were to be avoided. The PDP was applied to the results in the inclusion and exclusion tasks, to obtain indices of explicit/controlled (C ) and implicit/automatic (A ) memory. The C index was lowered by both BZs and A was equivalent in all treatments, confirming the general amnestic action of BZs. However, lorazepam led to decreases in completions in the indirect and inclusion tasks, while flunitrazepam impaired performance in the exclusion task. The qualitative differences between the drugs in their effects on performance suggest that these BZs may lead to differences in response bias. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In a parallel, double-blind study, 12 untreated hypertensive patients received terazosin (2-4 mg/day for 4 weeks), and 12 received placebo during the same period. Systolic and diastolic blood pressure decreased significantly in the terazosin group, from 150 ± 5.0 mmHg systolic and 99.6 ± 2.0 diastolic before treatment, to 134.0 ± 7.0 systolic and 85.6 ± 3.0 mmHg diastolic at week 4 of treatment. No significant blood pressure changes occurred in the placebo group. Blood pressure decrease showed a positive correlation (r = .62 and r = .52 for systolic and diastolic blood pressure, respectively) with the patient's age (P < .05). Total plasma cholesterol decreased 18% in the terazosin group (P < .05) and 9% in the placebo group (P > .05). Urinary dopamine excretion decreased significantly from 692.8 ± 180.0 to 330.5 ± 52.0 μg/24 hours in the terazosin group (P < .05) and showed a nonsignificant increase in the placebo group. Compared with 22 age- and sex-matched healthy volunteers, urinary dopamine excretion in the hypertensive group before treatment was not statistically different (779.3 ± 83.1 μg/24 hours). Dopamine excretion was higher in untreated hypertensive men and in male healthy volunteers compared with women. The decrease of urinary dopamine excretion observed under terazosin treatment could be due to a decrease of kidney dopamine synthesis or release induced by blood pressure reduction, or secondarily to the blockade of kidney α1-receptors, modulating dopamine excretion. No significant changes were observed in urinary excretion of noradrenaline and adrenaline. [ABSTRACT FROM AUTHOR]

At fixed bait stations in a large institutional setting in Brazil, the temporal and spatial pattern of usage of the dominant species of ant was studied. The ant Crematogaster cf. magnifica, was found in 91 % of sampling points. These studies were conducted using the same points as a previous study of the then dominant ant, Monomorium pharaonis, which was found to have declined from 93% to 3% spatial point occupation. The frequency of point usage during this study was significantly different from the Poisson distribution for both species, indicating non-random use of space. Crematogaster cf. magnifica was significantly more spatially exclusive than had been documented for M. pharaonis, and the probability of points originally occupied by M. pharaonis later becoming occupied by C. cf. magnifica was in excess of 90%. Temporal bait exploitation patterns of the two species did not differ. These data demonstrate that structural ant communities can change over time without human intervention, although short-term stability is characteristic of the urban dominant ants in subtropical Brazil. [ABSTRACT FROM AUTHOR]

The number of bacteria and yeasts occurring in the organic matter inside the nests were determined both in colonies of leaf-cutting ants reared on Eucaliptus alba (control) or Sesamum indicum (experimental). Sesame leaves induce imbalance and nests usually die. In control nests the number of bacteria in newer sponge and in older sponge were similar (3.6 × 105 and 1.4 × 105 CFU/g, respectively) whereas in waste deposit the mean reached 7.3 × 107 CFU/g. The Most Probable Number (MPN/g) of yeasts were 2.7 × 104, 1.3 × 105/g and 2.2 × 104 for newer sponge, older sponge and waste deposit, respectively. Using material from older sponge for comparison, the number of bacteria and yeasts reared on sesame leaves showed significant differences. The number of bacteria was 3.3 × 107 CFU/g, a value close to that found in waste deposit of normal (control) nests, whereas the number of yeasts was 6.7 × 105/g. These changes in microbial populations due to the effect of sesame leaf uptake could be a significant factor in nest imbalance and mortality when leaf-cutting ants are consuming toxic plants. [ABSTRACT FROM AUTHOR]

Mapping and collection of ants in cocoa trees in a 1 ha plot in the south of Bahia, Brazil, revealed three dominant species of the ant mosaic: Wasmannia auropunctata, Ectatomma tuberculatum and Azteca chartifex spiriti. A. chartifex demonstrated a larger influence in the cocoa plantation due to its spatial and temporal (1 y) stability in the same cocoa trees, and its capacity for territorial expansion. The management of A. chartifex for controlling insect pests of cocoa is strongly recommended. Considerations of temporal permanence of mosaic dominant ants should be a necessary criteria for ant management in tropical tree crops. [ABSTRACT FROM AUTHOR]

Laboratory colonies of the leaf-cutting ants Atta sexdens that were fed daily with leaves of Canavalia ensiformis showed a high ant mortality, and a significant decrease in fungal garden volume, with complete depletion of nests after 11 weeks of treatment. [ABSTRACT FROM AUTHOR]

The present study showed a strong deleterious effect on leaf-cutting ant Atta sexdens rubropilosa nests supplied exclusively with sesame ( Sesamum indicum) leaves in the laboratory. Sesame leaves were initially attractive to workers and later became antifeedant. Eucaliptus alba and Hibiscus rosu-sinensis leaves were used as control. [ABSTRACT FROM AUTHOR]

A letter to a editor is presented in response to an article on the nature of lorazepam effects by Vincenzo Di Lazzaro in the 2005 issue.

Objective: The purpose of the present study was to examine whether Alzheimer's Disease (AD) patients can benefit from the emotional content of visual stimuli in a picture recognition test., Methods: Sixteen patients with AD and 19 normal controls matched for age and years of education, were studied. Sixteen pictures (with varying emotional contents) were presented to each participant. Thirty minutes later, a recognition test was applied with the target-pictures mixed among 34 others of similar content. The subjects were instructed to rate them as pleasant, unpleasant or indifferent., Results: The total of pictures correctly recognized by the AD patients (75.4% of the target-pictures) was smaller than that of the controls (96.4%). Controls recognized more emotional pictures than indifferent pictures., Conclusion: Emotional content enhanced recognition of pictures in normal subjects, whereas for the Alzheimer's subjects the emotional significance attached to the pictures was of no benefit to enhance recognition.