Initial and resultant population densities in chickens between brooding and sexual maturity.

Seven flocks of chickens were raised in groups from weeks 5 to 9 after hatching. Initially the groups had the same number of chickens but they di0ered in population density. The number of birds that survived to week 9 was strongly related to the initial population density.

Smoking, processing speed and attention in a choice reaction time task.

Nineteen subjects performed a choice reaction time task in which two levels of choice (two and four stimuli), and two levels of spatial attention (narrow and wide) were manipulated under each of two smoking conditions: sham smoking (denicotinised cigarette) or regular smoking (0.8 mg nicotine cigarette). All three factors significantly affected reaction time, with the smallest reaction times being recorded to the two-choice narrow grouped stimuli recorded under the high nicotine condition. Nicotine appears to speed decision time for both complex and hard-to-attend tasks, which is compatible with a role for nicotinic receptors in systems jointly mediating attention, memory and processing speed.

Effects of smoking on simple and choice reaction time.

Twenty-nine subjects performed a reaction time task with four levels of choice-task complexity under non-smoking, sham smoking, and low, medium and high nicotine cigarette conditions. Nicotine reduced decision time, while sham smoking increased decision time. This effect was independent of subjects' habitual levels of cigarette consumption. No effect of smoking was found on movement time.

Smoking and Raven IQ.

Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks.

Effects of post-learning smoking on memory consolidation.

The effects of immediate post-learning smoking of low and medium nicotine delivery cigarettes were compared to those of smoking a denicotinised cigarette and a no-smoking control condition in a paired-associate learning task. Thirty-nine male smokers were tested for retention of the memorised material at 1 week post-learning. All subjects received all conditions in a repeated measures design. The low nicotine condition was associated with significantly fewer errors on first trial of recall and fewer total errors to criterion. There were no differences in performance reported between the no-smoking and zero nicotine conditions. The medium nicotine condition produced results part way between the no-smoking and low nicotine conditions. Results are discussed in terms of the effects of nicotine on long-term consolidation mechanisms.

Effects of nicotine on perceptual speed.

Two experiments investigating the effects of nicotine on performance in the inspection time (IT) procedure are reported. Experiment 1 compared ITs in smoking (0.8 mg nicotine cigarette), sham-smoking, and no-smoking conditions. IT was significantly shorter in the smoking condition as compared to both the no-smoking or sham-smoking conditions, suggesting that nicotine enhances early information processing. This result is of particular interest because of the correlation between IT and IQ reported in previous experiments. The nicotine related decrease in IT raises the possibility that nicotine enhances at least a subset of the physiological processes underlying intellectual performance. Experiment 2 examined the persistence of this nicotine related enhancement in IT, and investigated the effects of nicotine across 480 IT trials. Results suggested that ITs derived from the last third of the 480 trials were significantly shorter in the 0.8 mg cigarette condition than in no-smoking condition. The results from these two experiments, taken together with recent work examining the effects of nicotine on the string length measure of AEP waveform complexity and Hick decision time (DT), and studies investigating cognitive functioning and cholinergic system dysfunction in dementia, suggest a role of the cholinergic system in intellectual performance.

Comparison of PathVysion and INFORM fluorescence in situ hybridization kits for assessment of HER-2/neu status in breast carcinoma.

BACKGROUND: Fluorescence in situ hybridization is advocated for precise assessment of HER-2/neu status in breast carcinoma; however, few objective data compare available kits for clinical laboratories contemplating development of the test. METHODS AND RESULTS: Thirty breast carcinomas were analyzed for HER-2/neu amplification with the PathVysion kit (Vysis, Downers Grove, IL) and INFORM kit (Ventana Medical Systems, Tucson, AZ). Each kit was evaluated for morphology, background staining, technical and interpretation time, and cost. PathVysion detected amplification in seven of 30 cases (23.3%); INFORM detected six of 30 cases (20%). A greater percentage of PathVysion cases showed good morphology and lower background staining than INFORM. Technical and interpretation times, as well as cost, were less with PathVysion than INFORM. CONCLUSION: PathVysion is superior to INFORM because it produces better morphology and less background staining and is faster and less expensive than the INFORM kit. It also includes a chromosome 17 probe that serves as an internal control and enables correction for chromosome 17 aneuploidy.

HER-2/neu assessment in breast cancer by immunohistochemistry and fluorescence in situ hybridization: comparison of results and correlation with survival.

BACKGROUND: HER-2/neu immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) results guide breast cancer therapy; however, few studies compared the results and no published studies have correlated them with patient outcome. METHODS AND RESULTS: We compared results, cost, and turnaround time in 117 archival, invasive breast carcinomas and compared 50-month survival in 65 of these cases using commercial HER-2/neu IHC and FISH assays. Twenty-one of 112 FISH (19%) and 33 of 117 IHC cases (28%) were positive. Concordance was high overall (88%; 98 of 112 cases) and in IHC 3+ cases (88%; 14 of 16 cases) but low in IHC 2+ cases (35%; six of 17 cases). Survival correlated with IHC results in 3+ cases (P =.02) and FISH cases with signal ratio greater than 4.0 (P =.03), but not in IHC 2+ cases (P=.7). Cost and turnaround time were greater for FISH. CONCLUSION: IHC is appropriate for initial HER-2/neu assessment; however, patients with tumors scored less than 3+, particularly those interpreted as 2+, would benefit from FISH to more accurately assess HER-2/neu status and avoid inaccurate prognostication and inappropriate treatment.

The effects of cigarette smoking on verbal learning and retention.

The effects of smoking a low (.7 mg) and a middle (1.3 mg) nicotine yield cigarette on paired-associate learning and retention under conditions of high and low intralist interference, and on serial learning and retention, were examined in groups of male undergraduate smokers (N = 24). The interaction between nicotine level and task difficulty in paired-associate learning was marginally significant. The 1.3-mg nicotine dose impeded learning under low interference conditions, but facilitated learning of high interference sets. Both nicotine levels significantly improved retention in paired-associate learning; task difficulty appearing to have little relevance. Serial learning data suggested that the effect is shown on long-term, rather than short-term memory.

The relationship of mobility of inhibition to rate of inhibitory growth and measures of flexibility, extraversion, and neuroticism.

Measures of mobility of inhibition, and of internal, reactive and transmarginal inhibition, and inhibitory strength, which are claimed to index independent nervous system properties and personality dimensions, were obtained from a sample of 30 male undergraduates, and correlated with measures of sensorimotor, perceptual, and thinking flexibility, extraversion, and neuroticism. Results of a principal components analysis indicated that thinking flexibility and mobility of inhibition reflect speed of development of reactive inhibition, and the sensorimotor and perceptual flexibility are dependent on rate of growth of internal and transmarginal inhibition, respectively. Introverted Ss showed greater sensorimotor flexibility, but were less mobile, while Ss low on neuroticism were more flexible in perceptual tasks.

The effects of cigarette smoking on vigilance performance.

Each of 24 Ss completed an auditory vigilance task after smoking either a "low" nicotine cigarette (12 Ss) or a "middle" nicotine cigarette (12 Ss) and served as his own control in an identical session one week before or after the test session. The smoking was followed by improved vigilance in both groups as compared with the control performance. The improvement came about in different ways for the two groups. The low nicotine group recorded improved detection, the middle nicotine group reduced false positive rate. These effects are attributed to the known differential, biphasic effects of nicotine on performance.

The effects of smoking on memory consolidation.

The effects of smoking deprivation and of smoking a single .8 mg, 1.3 mg or 2 mg nicotine yield cigarette, immediately post acquisition on a paired-associate learning task, were studied in 54 male smokers and 15 male nonsmokers. Subjects were retested for retention of the memorized material at intervals of one-half hour, one day, one week, and one month. Nonsmokers showed superior recall to all smokers at one-half-hour retest, and to some of the smoking groups on later re-tests. At one-month retest the low- and middle-nicotine cigarette smokers outperformed high-nicotine cigarette smokers. Low/middle-nicotine smokers achieved superior recall to nonsmokers at one-month retest. Results are discussed in terms of smoker versus nonsmoker differences, in terms of the effects of nicotine on memory consolidation, and in terms of the PAL response measure adopted.

[Typology of the nervous system and personality]. / Tipologiia nervnoi sistemy i lichnost'.

The paper deals with structural organization of psycho-physiological and psychological characteristics of personality. The following characteristics were estimated: psychomotor, intellectual, creative abilities, features of imagination as well as basic properties of personality: extraversion--introversion, and neuroticism. Using the Q-technique of factor analysis of the 1-st, 2-nd and 3rd orders, the authors singled out three types of psychophysiological and psychological human organization. Each type was given a generalized interpretation. Conclusion is made that these types reflect more generalized processes than factors derived with R-technique of factor analysis.

Oestrogen-dependent satellite cell activation and proliferation following a running exercise occurs via the PI3K signalling pathway and not IGF-1.

AIM: The purpose of this study was to determine whether 17ß-estradiol (E2) enhances the activation, proliferation and differentiation of muscle satellite cells (SC) following eccentric exercise either via insulin-like growth factor-1 (IGF-1) or through phosphatidylinositol 3-kinase (PI3K) signalling. METHODS: This study used 64, 9-week-old, ovariectomized Sprague-Dawley rats that were divided into eight treatments groups based on oestrogen status (0.25 mg oestrogen pellet or sham), exercise status (90 min run @ 17 m min(-1), -13.5° or unexercised) and PI3K signalling inhibition (0.7 mg wortmannin kg(-1) body weight or DMSO control). RESULTS: Significant increases in total SCs were found in both soleus and white gastrocnemius muscles (immunofluorescent co-localization of Pax7(+) nuclei) 72 h following eccentric exercise (P < 0.05). Oestrogen supplementation caused a further enhancement in total SCs in exercised rats (P < 0.05). In animals where the PI3K pathway was inhibited, regardless of oestrogen or exercise status, there was no significant enhancement of SC number in both the soleus or white gastrocnemius muscles. Interestingly, oestrogen supplementation lowered muscle levels of IGF-1 with this effect being most prominent in the soleus muscle. While IGF-1 was increased following exercise (P < 0.05), oestrogen supplementation abrogated this increase back to sedentary levels. CONCLUSION: These data suggest that the increase in SC population following exercise in oestrogen-supplemented females may be mediated via PI3K pathway signalling and not IGF-1.

Personality and conditioning: factors of classical CR acquisition and extinction and their relationship to personality types.

A number of psychophysiological, cognitive and personality measures, and classical appetitive and aversive SR acquisition and extinction rates were taken from a sample of 25 male undergraduate volunteers. Principal Components Analysis of the data revealed general acquisition and extinction factors which were indexed by the psychophysiological variables. Regression analyses showed additionally that Eysenck's E-I dimension predicts both acquisition and extinction rates, and that imagery may be an important mediational variable in CR acquisition.

Inhibitory ease--a personality type?

Measures of reactive, transmarginal and internal inhibition, inhibitory strength, extraversion (E) and neuroticism (N) were obtained from a sample of 25 Ss. A Principal Components analysis of the data disclosed factors which were identified tentatively as extinctive/reactive inhibition, transmarginal inhibition, and appetitive and aversive inhibitory strength. N loaded the transmarginal inhibition factor, and I(Introversion) the appetitive inhibitory strength factor. It is suggested that the role of E in appetitive CR extinction may be a function of the extent to which inhibitory strength is involved in inhibitory dynamism.