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There is increasing recognition that using assistive devices can support healthy aging. Minimizing discomfort and loss of function and increasing independence can have a substantial impact physically, psychologically, and financially on persons with functional impairments and resulting activity limitations, as well as on caregivers and communities. However, it remains unclear who uses assistive devices and how device use can influence social participation. The current analysis used CLSA baseline data from 51,338 older adults between the ages of 45 and 85. Measures of socio-demographic, health, and social characteristics were analyzed by sex and age groups. Weighted cross-tabulations were used to report correlations between independent variables and assistive device use for hearing, vision, and mobility. We found that assistive device use was higher among those who were of older age, had less education, were widowed, had lower income, and had poorer health. Assistive devices were used differently according to sex and social participation, providing insight into assistive device use for the well-being of older adults and their families.

Background Recognizing that attention is not a unitary system, the Attention Network Test (ANT) and its variants were developed to measure the efficacy of the multiple components of attention. One potential weakness of these tests (ANTs) is that they are unengaging. This poses a problem when particular groups are tested (e.g., young children), when more stable measures of performance are desirable (and can only be achieved in longer testing sessions) and when repeated testing is necessary. New method Here we describe the evolution of a game-like tool, which we call the AttentionTrip©, that is suitable for investigating three isolable attentional networks (alerting, orienting, and executive functions). Results Utilizing this tool we were able to generate reasonable network scores for alerting, executive control (from both the flanker and Simon effects), endogenous orienting and, after some motivated modifications, exogenous orienting. Comparison with existing method(s) Split-half reliabilities of the alerting and executive (flanker) network scores were considerably higher than those reported by MacLeod et al. (2010) in their psychometric review of the ANT. Informal observations (e.g., some participants asking if they could keep doing the task when their session was over) suggesting that the AttentionTrip is considerably more engaging than the traditional ANT have been confirmed in a head-to-head comparison (Vallis & Klein, 2016). Conclusions The AttentionTrip@ is available now for research purposes. A tablet version, which will have greater clinical utility, is under development.

Prism adaptation (PA) is a promising rehabilitation technique for visuo-spatial neglect, an attention disorder that is characterized by spatial attention deficits (i.e., deficits in orienting). PA involves visuo-motor adaptation to rightward shifting prism goggles. Following goggle removal, this adaptation results in leftward shifts in visuo-motor aiming and amelioration of spatial neglect. Even though some studies clearly support the beneficial effects of PA for spatial neglect, not all studies find benefits, thus it remains unclear how PA effects could be improved. Taking advantage of the known interactions between orienting and alerting reported in the attention literature (i.e., alerting enhances orienting function; e.g., Ishigami and Klein in J Individ Differ 30:220-237. doi: 10.1027/1614-0001.30.4.220 , 2009, in J Neurosci Methods 190:117-28. doi: 10.1016/j.jneumeth.2010.04.019 , 2010; Robertson et al. in Nature 395:169-72. doi: 10.1038/25993 , 1998), we examined the effects of alerting tones on PA with healthy young and older adults. We found that the effects of alerting on PA with young adults were negative, while there was a positive effect with older adults, specifically on a visuo-motor outcome task. Thus, enhancement of PA effects by alerting may be age specific and task specific. Therefore, we can conclude that while the impact of alerting tones is not always positive, further research in patients with neglect may be warranted.

The current study examined the robustness, stability, reliability, and isolability of the attention network scores (alerting, orienting, and executive control) when young children experienced repeated administrations of the child version of the Attention Network Test (ANT; Rueda et al., 2004). Ten test sessions of the ANT were administered to 12 young children. Participants were asked to indicate the direction of a target fish, flanked by distractors, presented either above or below the fixation cross following different types of visual cues. Network scores, reflecting alerting, orienting, and executive control, were calculated using orthogonal subtractions of performance in selected conditions. Only the alerting network scores remained highly significant across the 10 sessions. The executive network scores showed some practice effects. The reliability of the network scores remained poor regardless of the amount of data. Based on the results, use of the ANT is cautioned against in young children when repe...

Impairments in information processing speed are common in multiple sclerosis (MS), with affected individuals demonstrating slower responses and more intraindividual variability (IIV) in their performance on timed tasks. Evidence suggesting that IIV provides novel information about cognitive deficits in MS is accumulating; however, little is known about the stability of IIV across multiple assessments. In this study, we investigated IIV in response speed in persons with MS across 6 monthly sessions using the Attention Network Test-Interaction (ANT-I).Individuals with relatively mild relapsing remitting MS and healthy controls completed the ANT-I at 6 monthly intervals. Clinical assessments (Sessions 1 and 6) and conventional magnetic resonance imaging (MRI) studies (Sessions 1-6) were examined for individuals with MS.The MS group's clinical and neuroimaging measures were stable during the 6-month period. Individuals with MS were slower and more variable in reaction time performance on the ANT-I than were controls. Differences in IIV between groups were maintained across the 6 sessions, with IIV demonstrating less susceptibility to across-session practice effects than mean latency scores.IIV provides a stable measure of cognitive performance in mildly affected persons with MS who are clinically and radiologically stable. Further studies exploring its utility as a clinical outcome are warranted.

Many biological activities of green tea have been attributed to a major constituent, (minus;)-epigallocatechin gallate (EGCG). We previously reported that EGCG and an EGCG-free fraction derived from green tea modulated the gene expression of gluconeogenic enzymes, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, in the mouse liver. EGCG is also known to affect the gene expression of enzymes related to lipid metabolism. However, it remains to be examined whether or not a constituent other than EGCG contributes to the change in gene expression of these enzymes. In this study, we prepared an EGCG-free water-soluble fraction (GT-W), and examined its effects on the hepatic gene expression of lipogenic enzymes in mice. The results of quantitative real-time PCR assays indicated that the dietary administration of GT-W for 4 weeks reduced the hepatic gene expression of lipogenic enzymes: fatty acid synthase, hydroxymethylglutaryl coenzyme A reductase, and acetyl-coenzyme A carboxylase alpha. Also, the gene expression of sterol regulatory element-binding transcription factor (Srebf)1 and/or Srebf2 was reduced, suggesting that the reduction of Srebfs contributed to the down-regulation of the lipogenic enzymes, since these transcription factors bind the promoter region to enhance their expression. The plasma levels of triglycerides and cholesterol were reduced with statistical significance in the group given a diet containing GT-W. These results suggest that in addition to EGCG, green tea contains some component(s) which may help to prevent arteriosclerosis and obesity.

Many biological activities of green tea have been attributed to a major constituent, (-)-epigallocatechin gallate (EGCG). We previously reported that EGCG and a catechin-rich green tea beverage modulated the gene expression of gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), in the mouse liver. However, it remains to be examined whether or not a constituent other than EGCG contributes to the change in gene expression of these enzymes. In this study, we separated the hot water infusion of green tea leaves (GT) into an ethanol-soluble fraction (GT-E) and an EGCG-free water-soluble fraction (GT-W), and examined their effects using rat hepatoma H4IIE cells. The inclusion of GT, GT-E, and GT-W in the culture medium reduced the gene expression of G6Pase and PEPCK. GT-W caused a decrease in expression of the transcription factor HNF4α. Reduced levels of PEPCK and HNF4α proteins were demonstrated in the cells treated with GT-W. GT-W showed an activity similar to insulin, but different from EGCG. Administration of GT-W to mice for 4 weeks reduced the hepatic expression of G6Pase, PEPCK, and HNF4α. These results suggest that green tea contains some component(s) with insulin-like activity distinguishable from EGCG and that drinking green tea may help to prevent diabetes.

Using orthogonal subtractions of performance in selected conditions the attentional network test (ANT) measures the efficacy of three isolable components of attention: alerting, orienting, and executive control. Ten test sessions, each containing two versions of the ANT (Fan et al., 2002; Callejas et al., 2005), were administered to 10 young adults to examine stability, isolability, robustness, and reliability of the tests. Participants indicated the direction of a target arrow presented either above or below the fixation. The target arrow was accompanied by distracting arrows, either pointing to the same direction (congruent) as or the opposite direction (incongruent) to the target arrow. The arrows were preceded by informative visual cues (central, double, spatial, and no cue) differing in temporal and spatial information (Fan et al.) or by alerting auditory signals (tone and no tone) and uninformative visual cues (valid, invalid, and no cue) (Callejas et al.). All network scores remained highly significant even after nine previous sessions despite some practice effects in the executive and the orienting networks. Some lack of independence among the networks was found. The relatively poor reliability of network scores with one session of data rises to respectable levels as more data is added.

Modulation of attentional capture by attentional control settings was explored using performance and phenomenology. Trials began with four figure-8s presented above, below, left, and right of fixation. Any figure-8 (or none) brightened uninformatively (cue) before presentation of either a digit target (2 or 5 made from a figure-8 by deletion) calling for a speeded identification, or a line connecting adjacent figure-8s calling for a motion judgement. Such lines are seen drawn away from an adjacent cue. Digit targets appeared only on the horizontal or vertical axes, encouraging voluntary attention to two (target-relevant) of the four figure-8s. Whereas voluntary attention reduced attentional capture from cues at taskirrelevant locations (when lines were unlikely to be presented near the task-irrelevant locations), it had no effect on motion judgements, suggesting that cue-elicited exogenous attention affects perceptual arrival times while voluntary attention prioritizes locations for further processing wit...

We administered the Cognitive Failures Questionnaire (CFQ) and one of two versions of the Attention Network Test (ANT) to 200 participants. Orthogonal subtraction scores based on performance (reaction time and error rate) from selected conditions of the ANT provided measures of the efficacy of three attention components: alerting, orienting, and executive control, while the total CFQ score provided a global measure of absentmindedness. Executive control was not associated with the CFQ in either experiment. When alertness was generated by a warning tone, greater alerting effects in reaction time were associated with higher CFQ scores (greater absentmindedness). The orienting effects in accuracy obtained from the two versions of the ANT varied with absentmindedness in opposite directions, suggesting that these two tests tap different aspects of orienting.

Green tea and its constituent (-)-epigallocatechin-3-O-gallate (EGCG) are known to have apoptosis-inducing activity on tumor cells including human leukemia HL-60 cells, providing an explanation for their anti-cancer effects. In the present study, we compared the sensitivity of undifferentiated cells and differentiated HL-60 cells with normal-like phenotypic characters. HL-60 cells treated with three differentiating agents were found to be resistant to EGCG-mediated apoptosis as compared with undifferentiated cells. Gene and protein expression of 67 kDa laminin receptor was down-regulated in differentiated HL-60 cells, suggesting its contribution to the difference in sensitivity in view of the fact that the receptor is a target of EGCG's action to induce apoptosis. The finding supports the view that EGCG induces apoptosis preferentially in cancer cells as compared with normal counterparts.

Auditory saltation is the orderly misperception of the spatial location of repetitive click stimuli emitted from two successive locations when the inter-click intervals (ICIs) are sufficiently short. The clicks are perceived as originating not only from the actual source locations, but also from locations between them. In two tasks, the present experiment compared free-field auditory saltation for 90 degrees excursions centered in the frontal, rear, left and right acoustic hemifields, by measuring the ICI at which subjects report 50% illusion strength (subjective task) and the ICI at which subjects could not distinguish real motion from saltation (objective task). A comparison of the saltation illusion for excursions spanning the midline (i.e. for frontal or rear hemifields) with that for stimuli in the lateral hemifields (left or right) revealed that the illusion was weaker for the midline-straddling conditions (i.e. the illusion was restricted to shorter ICIs). This may reflect the contribution of two perceptual channels to the task in the midline conditions (as opposed to one in the lateral hemifield conditions), or the fact that the temporal dynamics of localization differ between the midline and lateral hemifield conditions. A subsidiary comparison of saltation supported in the left and right auditory hemifields, and therefore by the right and left auditory forebrains, revealed no difference.

We extend the finding that word reading slows following successful responses to a color-word Stroop interference task (Masson, Bub, Woodward,Chan, 2003). Word reading was assessed in a picture-word interference task in which subjects alternated between naming a picture (with either a word or a row of Xs superimposed on it) and reading a word. For the word-reading task, words were presented either in isolation or superimposed on a picture. Word reading was slower after subjects responded to a bivalent stimulus that required resolution of conflict (naming a picture with a word superimposed on it) than after they responded to a stimulus that involved no conflict (naming a picture with Xs superimposed on it), indicating modulation of dominant task performance. This effect was found when word-reading targets were superimposed on pictures but not when those targets were presented in isolation. Modulation of word reading, therefore, appears to be the result of interference from a persistent picture-naming task set, cued by a stimulus configuration that invites execution of both competing tasks.

Prism adaptation (PA) is both a perceptual-motor learning task as well as a promising rehabilitation tool for visuo-spatial neglect (VSN) – a spatial attention disorder often experienced after stroke resulting in slowed and/or inaccurate motor responses to contralesional targets. During PA, individuals are exposed to prism-induced shifts of the visual-field while performing a visuo-guided reaching task. After adaptation, with goggles removed, visuo-motor responding is shifted to the opposite direction of that initially induced by the prisms. This visuo-motor aftereffect has been used to study visuo-motor learning and adaptation and has been applied clinically to reduce VSN severity by improving motor responding to stimuli in contralesional (usually left-sided) space. In order to optimize PA’s use for VSN patients, it is important to elucidate the neural and cognitive processes that alter visuomotor function during PA. In the present study, healthy young adults underwent PA while event-related potentials (ERPs) were recorded at the termination of each reach (screen-touch), then binned according to accuracy (hit vs. miss) and phase of exposure block (early, middle, late). Results show that two ERP components were evoked by screen-touch: an early error-related negativity (ERN), and a P300. The ERN was consistently evoked on miss trials during adaptation, while the P300 amplitude was largest during the early phase of adaptation for both hit and miss trials. This study provides evidence of two neural signals sensitive to visual feedback during PA that may sub-serve changes in visuomotor responding. Prior ERP research suggests that the ERN reflects an error processing system in medial-frontal cortex, while the P300 is suggested to reflect a system for context updating and learning. Future research is needed to elucidate the role of these ERP components in improving visuomotor responses among individuals with VSN.

The Attention Network Test (ANT) is a frequently used computer-based tool for measuring the three attention networks (alerting, orienting, and executive control). We examined the psychometric properties of performance on a variant of the ANT, the Attention Network Test-Interaction (ANT-I) in healthy older adults (N = 173; mean age = 65.4, SD = 6.5; obtained from the Brain in Motion Study, Tyndall et al. BMC Geriatr 13:21, 2013. doi: 10.1186/1471-2318-13-21) to evaluate its usefulness as a measurement tool in both aging and clinical research. In terms of test reliability, split-half correlation analyses showed that all network scores were significantly reliable, although the strength of the correlations varied across networks as seen before (r = 0.29, 0.70, and 0.68, for alerting, orienting, and executive networks, respectively, p’s < 0.05). In terms of construct validity, ANOVAs confirmed that each network score was significant (18.3, 59.4, and 109.2 ms for the alerting, orienting, and executive networks, respectively, p’s < 0.01) and that these scores were generally independent from each other. Importantly, for criterion validity, a series of hierarchical linear regressions showed that the executive network score, in addition to demographic information, was a significant predictor of performance on tests of conflict resolution as well as verbal memory and retrieval (β = −0.165 and −0.184, p’s < 0.05, respectively). These results provide new information regarding the reliability and validity of ANT-I test performance in a healthy older adult population. The results provide insights into the psychometrics of the ANT-I and its potential utility in clinical research settings.

Residual switch costs are notoriously difficult to eliminate. Yet Hunt and Klein (2002) eliminated them in a task that required observers to alternate between 8 trials of prosaccades and 8 trials of antisaccades, as long as there was at least 1 sec between the task cue and the onset of the saccade target. It was proposed that the elimination of residual switch costs occurred because prosaccade responses are computed very rapidly. These so-called hypercompatible responses bypass memory retrieval stages of the response process, thereby eliminating the source of residual switch costs. Here we tested this hypothesis by requiring observers to alternate between responding with the finger that was vibrated (another task that meets the criteria for hypercompatibility) and responding with the finger of the opposite hand. Residual switch costs were not eliminated, suggesting that their elimination in Hunt and Klein (2002) was due to special properties of the prosaccade-antisaccade task.

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). This reprinted article has been retracted at the request of the Publisher. The online version of this reprint has been withdrawn as it was a redundant duplicate of the original article. The original can be found via http://dx.doi.org/10.1016/j.jsr.2009.02.006 . The Publisher apologizes for any inconvenience this may cause.

Our conception of attention is intricately linked to limited processing capacity and the consequent requirement to select, in both space and time, what objects and actions will have access to these limited resources. Seminal studies by Treisman (Cognitive Psychology, 12, 97-136, 1980) and Broadbent (Perception and Psychophysics, 42, 105-113, 1987; Raymond et al. Journal of Experimental Psychology: Human Perception and Performance, 18, 849-860, 1992) offered the field tasks for exploring the properties of attention when searching in space and time. After describing the natural history of a search episode we briefly review some of these properties. We end with the question: Is there one attentional "beam" that operates in both space and time to integrate features into objects? We sought an answer by exploring the distribution of errors when the same participant searched for targets presented at the same location with items distributed over time (McLean et al. Quarterly Journal of Experimental Psychology, 35A, 171-186, 1982) and presented all at once with items distributed over space (Snyder Journal of Experimental Psychology; 92, 428-431, 1972). Preliminary results revealed a null correlation between spatial and temporal slippage suggesting separate selection mechanisms in these two domains.

The Attention Network Test (ANT) assesses the networks of attention (alerting, orienting, and executive control). The utility of measuring attention network performances with the repeated administration of the ANT in clinical populations has not yet been explored. In the present study, we administered a variant of the ANT (ANT-I) to 11 multiple sclerosis (MS) patients and 11 controls over six monthly sessions to examine the stability, isolability, robustness, and reliability of the ANT-I. Participants responded through button presses to indicate the direction of a target arrow presented either above or below a fixation cross. The target was accompanied by distracting arrows, pointing either in the same or opposite direction of the target arrow. Target arrows were preceded in some trials by alerting auditory signals and/or by uninformative visual cues. Network scores were calculated using orthogonal subtractions of performance under selected conditions. The MS patients were slower than the controls, though group differences in network performance were rare. Even after five test sessions, the network scores remained stable, despite some practice effects that were the largest under conditions that tested the executive network. The reliabilities of the orienting and executive network effects were good in both groups and increased across sessions, especially with the MS patients. The alerting network was the least reliable, especially for MS patients, but it also became more reliable across sessions. The results suggest that the ANT-I can be used to measure the integrity of attention networks for MS patients in applications that require repeated testing.

Our conception of attention is intricately linked to limited processing capacity and the consequent requirement to select, in both space and time, what objects and actions will have access to these limited resources. Seminal studies by Treisman(Cognitive Psychology, 12, 97-136, 1980) and Broadbent (Perception and Psychophysics, 42, 105-113, 1987; Raymond et al. Journal of Experimental Psychology: Human Perception and Performance, 18, 849-860, 1992) offered the field tasks for exploring the properties of attention when searching in space and time. After describing the natural history of a search episode we briefly review some of these properties. We end with the question: Is there one attentional “beam” that operates in both space and time to integrate features into objects? We sought an answer by exploring the distribution of errors when the same participant searched for targets presented at the same location with items distributed over time (McLean et al. Quarterly Journal of Experimental Psychology, 35A, 171–186, 1982) and presented all at once with items distributed over space (Snyder Journal of Experimental Psychology, 92, 428–431, 1972). Preliminary results revealed a null correlation between spatial and temporal slippage suggesting separate selection mechanisms in these two domains.

Ishigami and Klein (2010) showed that scores of the three attention networks (alerting, orienting, and executive control) measured with the two versions of the Attention Network Test (ANT; Fan et al., 2002; Callejas et al., 2005) were robust over 10 sessions of repeated testing even though practice effects were consistently observed especially in the executive network when young adults were tested. The current study replicated their method to examine robustness, stability, reliability, and isolability of the networks scores when older adults were tested with these ANTs. Ten test sessions, each containing two versions of the ANT, were administered to 10 older adults. Participants were asked to indicate the direction of a target arrow, flanked by distractors, presented either above or below the fixation following auditory signals or/and visual cue. Network scores were calculated using orthogonal subtractions of performance in selected conditions. All network scores remained highly significant even after nine previous sessions despite some practice effects in the executive and the alerting networks. Some lack of independence among the networks was found. The relatively poor reliability of network scores with one session of data rises to respectable levels as more data is added.

Green tea has been shown to have many beneficial health effects. We have previously reported that dietary (-)-epigallocatechin-3-O-gallate (EGCG), the major polyphenol in green tea, reduced gene expressions of gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), in the normal mouse liver. In the present study, we examined the effects of intragastrical administration of EGCG on the expression of gluconeogenesis-related genes in the mouse intestine. The results of experiments with the semi-quantitative reverse transcription-polymerase chain reaction indicated that EGCG at 0.6 mg/head caused a reduced expression of G6Pase, PEPCK, hepatocyte nuclear factor 1α (HNF1α), and HNF4α. Experiments using the quantitative real-time polymerase chain reaction confirmed these effects. We then examined the effects of EGCG using human colon carcinoma Caco-2 cells stimulated with dexamethasone and dibutyryl cAMP. The results were generally consistent with those from the experiments in vivo. The present findings suggest EGCG to contribute to the beneficial effects of green tea on diabetes, obesity, and cancer by modulating gene expression in the intestine.

Automatic attentional capture by a salient distractor can be prevented by spatial attentional control settings (ACSs) (e.g., Yantis and Jonides in J Exp Psychol Hum Percept Perform 16:121–134, 1990). Earlier, converging evidence for a spatial ACS (Eason et al. 1969) was found in event-related potentials (ERPs). In these studies, the ACS was defined by a single target-relevant location. In an extension, Ishigami et al. (Vis Cogn 17:431–456, 2009) demonstrated a successful ACS in performance that was based on multiple (two) target-relevant locations. The purpose of the current study is to seek converging evidence from ERPs for a spatial ACS defined by multiple (two) target-relevant locations, using the methods in Ishigami et al. (Vis Cogn 17:431–456, 2009). Any one of four figure-8s brightened uninformatively (cue) before presentation of a digit target calling for a speeded identification (2 or 5). A spatial ACS was encouraged because in different blocks, the digit targets appeared only on the horizontal or vertical axis. Performance was more impaired following the invalid-attended cues than following invalid-unattended cues, consistent with Ishigami et al. (Vis Cogn 17:431–456, 2009) and verifying a successful spatial ACS. The direction of attention significantly affected the visual evoked potentials (VEPs) elicited by otherwise identical cues: the amplitudes of early VEPs were greater when the location the cue was presented in was target-relevant than when the location was target-irrelevant. These results re-affirm that attentional capture by irrelevant salient stimuli can be modulated by spatial ACSs defined by multiple target locations in performance and provide converging evidence from ERPs for the previously established behavioral findings.

Tea has many beneficial effects. We have previously reported that green tea and a catechin-rich green tea beverage modulated the gene expression of the gluconeogenic enzymes glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) in the normal murine liver. In the present study, we examined the effects of oral administration of oolong tea on the hepatic expression of gluconeogenesis-related genes in the mouse. The intake of oolong tea for 4 weeks reduced the hepatic expression of G6Pase and PEPCK together with that of the transcription factor hepatocyte nuclear factor (HNF) 4α. When rat hepatoma H4IIE cells were incubated in the presence of oolong tea, the expression of these genes was repressed in accordance with the findings in vivo. The reduced protein expression of PEPCK and HNF4α was also demonstrated. We then fractionated oolong tea by sequential extraction with three organic solvents to give three fractions and the residual fraction (Fraction IV). In addition to organic fractions, Fraction IV, which was devoid of low-molecular-weight catechins such as (-)-epigallocatechin gallate (EGCG), had effects similar to those of oolong tea on H4IIE cells. Fraction IV repressed the gene expression of insulin-like growth factor binding protein 1, as insulin did. This activity was different from that of EGCG. The present findings suggest that drinking oolong tea may help to prevent diabetes and that oolong tea contains a component or components with insulin-like activity distinguishable from EGCG. Identification of such component(s) may open the way to developing a new drug for diabetes.

Rat hepatoma H4IIE cells were stimulated with dexamethasone and dibutyryl cAMP to increase gene expressions of gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK). Inclusion of catechin-rich green tea beverage (GTB) in the culture medium reduced the up-regulation of these genes as well as that of hepatocyte nuclear factor 4 alpha (HNF4alpha) gene. GTB was fractionated into chloroform-soluble (Fraction I), ethyl acetatesoluble (Fraction II), methanol-soluble (Fraction III) and residual (Fraction IV) fractions. Fractions II and III containing catechins caused an attenuation of the up-regulated expression of these genes as well as the down-regulation of HNF4alpha gene expression. Fraction IV had a synergistic effect on the up-regulation by dexamethasone/dibutyryl cAMP of the PEPCK gene expression and upregulated HNF4alpha gene expression. These results suggest that GTB down-regulated the expression of the HNF4alpha gene to cause the down-regulated gene expression of gluconeogenic enzymes. One reason why GTB did not down-regulate hepatic PEPCK gene expression in previous animal experiments may be that the component(s) acting to up-regulate PEPCK gene expression was more effective in vivo than in cultured cells.

The importin/exportin transport system provides the machinery involved in nucleocytoplasmic transport. Alterations of the levels of importins and exportins may play crucial roles in development, differentiation and transformation. Employing human leukaemia HL-60 cells, we and others have revealed the differentiation-associated changes in the protein and gene expression of these factors. The recent finding that a switch to the importin-alpha subtype triggers neural differentiation of embryonic stem cells underscores the importance of nucleocytoplasmic transport factors in cellular events. This review focuses on current research into the roles of importins and exportins in cell differentiation.

INTRODUCTION: Although it is becoming more and more accepted that driving while talking on a cell phone can be hazardous, most jurisdictions are making handheld phone use illegal while allowing hands-free phone use. METHODS: The scientific literature exploring the effects of these two types of cell phone use on driving and driving-related performance is reviewed here. RESULTS: Our review shows that talking on the phone, regardless of phone type, has negative impacts on performance especially in detecting and identifying events. Performance while using a hands-free phone was rarely found to be better than when using a handheld phone. Some studies found that drivers compensate for the deleterious effects of cell phone use when using a handheld phone but neglect to do so when using a hands-free phone. IMPACT ON INDUSTRY: Current research does not support the decision to allow hands-free phone use while driving. Keywords: Driver distraction; Language: en

Employing the DNA microarray technique, we previously reported the alteration in gene expression of nucleocytoplasmic transport factors, importins and exportins, induced by 1,25-dihydroxyvitamin D3 (DVD) in human leukemia HL-60 cells. Here, we used the quantitative reverse transcription-polymerase chain reaction method to confirm such previous findings, and compared them with those from the cells treated with all-trans-retinoic acid (ATRA). The results indicated that the gene expression of the transport factors examined was mostly down-regulated following differentiation induced by DVD and ATRA, but importin alpha5 gene expression was up-regulated in either case. The differences were found in the gene expression of importin alpha3 and exportin 6 between the cells after treatments with DVD and ATRA. These variations may be related to the difference between HL-60 cell lineages differentiating into monocytes/macrophages and granulocytes. The present findings provide further evidence to support the important roles of importins and exportins in cell differentiation.