3,080 research outputs found

    Acute effects of nicotine on visual search tasks in young adult smokers

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    Rationale Nicotine is known to improve performance on tests involving sustained attention and recent research suggests that nicotine may also improve performance on tests involving the strategic allocation of attention and working memory. Objectives We used measures of accuracy and response latency combined with eye-tracking techniques to examine the effects of nicotine on visual search tasks. Methods In experiment 1 smokers and non-smokers performed pop-out and serial search tasks. In experiment 2, we used a within-subject design and a more demanding search task for multiple targets. In both studies, 2-h abstinent smokers were asked to smoke one of their own cigarettes between baseline and tests. Results In experiment 1, pop-out search times were faster after nicotine, without a loss in accuracy. Similar effects were observed for serial searches, but these were significant only at a trend level. In experiment 2, nicotine facilitated a strategic change in eye movements resulting in a higher proportion of fixations on target letters. If the cigarette was smoked on the first trial (when the task was novel), nicotine additionally reduced the total number of fixations and refixations on all letters in the display. Conclusions Nicotine improves visual search performance by speeding up search time and enabling a better focus of attention on task relevant items. This appears to reflect more efficient inhibition of eye movements towards task irrelevant stimuli, and better active maintenance of task goals. When the task is novel, and therefore more difficult, nicotine lessens the need to refixate previously seen letters, suggesting an improvement in working memory

    Frequency of complementary and alternative medicine utilization in hypertensive patients attending an urban tertiary care centre in Nigeria

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    <p>Abstract</p> <p>Background</p> <p>To study the frequency and pattern of use of complementary and alternative medicine (CAM) in patients with essential hypertension attending a tertiary hypertension clinic.</p> <p>Methods</p> <p>Two hundred and twenty-five consecutive hypertensive patients attending the hypertension clinic of the Lagos University Teaching Hospital over a 3-month period were interviewed. Socio-demographic data, duration of hypertension, clinic attendance, current blood pressure, and compliance to conventional medications was documented. CAM utilization was explored using both structured and open-ended questions.</p> <p>Results</p> <p>There were 90 (40%) male and 135 (60%) female patients with mean age ± SD overall was 55.1 ± 12.4 years. 88 (39.1%) of the respondents used CAM. Herbal products were the most commonly used CAM type. Amongst the CAM users, the most common herbal product used was garlic (69.3%). Others were native herbs (25%), ginger (23.9%), bitter leaf (<it>Vernonia amygdalina</it>) (9.1%), and aloe vera (4.5%). 2.5% used spiritual therapy. There was no difference in the clinical characteristics, socio-economic status, and blood pressure control of CAM users and non-users. Patients who utilized CAM had higher BMI compared with those who did not, but the difference was not statistically significant (mean BMI ± SD of 29.1 ± 5.6 vs 27.1 ± 5.9 kg/m<sup>2</sup>; P = 0.05).</p> <p>Conclusion</p> <p>A significant proportion of hypertensive patients attending our tertiary facility and receiving conventional treatment also use CAM therapies. Clinicians need to be aware of this practice, understand the rationale for this health-seeking behaviour, proactively enquire about their use, and counsel patients regarding the potential of some of the therapies for adverse reactions and drug interactions.</p

    Sensory Electrical Stimulation Improves Foot Placement during Targeted Stepping Post-Stroke

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    Proper foot placement is vital for maintaining balance during walking, requiring the integration of multiple sensory signals with motor commands. Disruption of brain structures post-stroke likely alters the processing of sensory information by motor centers, interfering with precision control of foot placement and walking function for stroke survivors. In this study, we examined whether somatosensory stimulation, which improves functional movements of the paretic hand, could be used to improve foot placement of the paretic limb. Foot placement was evaluated before, during, and after application of somatosensory electrical stimulation to the paretic foot during a targeted stepping task. Starting from standing, twelve chronic stroke participants initiated movement with the non-paretic limb and stepped to one of five target locations projected onto the floor with distances normalized to the paretic stride length. Targeting error and lower extremity kinematics were used to assess changes in foot placement and limb control due to somatosensory stimulation. Significant reductions in placement error in the medial–lateral direction (p = 0.008) were observed during the stimulation and post-stimulation blocks. Seven participants, presenting with a hip circumduction walking pattern, had reductions (p = 0.008) in the magnitude and duration of hip abduction during swing with somatosensory stimulation. Reductions in circumduction correlated with both functional and clinical measures, with larger improvements observed in participants with greater impairment. The results of this study suggest that somatosensory stimulation of the paretic foot applied during movement can improve the precision control of foot placement

    Stochastic Modeling for the Expression of a Gene Regulated by Competing Transcription Factors

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    It is widely accepted that gene expression regulation is a stochastic event. The common approach for its computer simulation requires detailed information on the interactions of individual molecules, which is often not available for the analyses of biological experiments. As an alternative approach, we employed a more intuitive model to simulate the experimental result, the Markov-chain model, in which a gene is regulated by activators and repressors, which bind the same site in a mutually exclusive manner. Our stochastic simulation in the presence of both activators and repressors predicted a Hill-coefficient of the dose-response curve closer to the experimentally observed value than the calculated value based on the simple additive effects of activators alone and repressors alone. The simulation also reproduced the heterogeneity of gene expression levels among individual cells observed by Fluorescence Activated Cell Sorting analysis. Therefore, our approach may help to apply stochastic simulations to broader experimental data

    A falls prevention programme to improve quality of life, physical function and falls efficacy in older people receiving home help services: study protocol for a randomised controlled trial

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    BACKGROUND: Falls and fall-related injuries in older adults are associated with great burdens, both for the individuals, the health care system and the society. Previous research has shown evidence for the efficiency of exercise as falls prevention. An understudied group are older adults receiving home help services, and the effect of a falls prevention programme on health-related quality of life is unclear. The primary aim of this randomised controlled trial is to examine the effect of a falls prevention programme on quality of life, physical function and falls efficacy in older adults receiving home help services. A secondary aim is to explore the mediating factors between falls prevention and health-related quality of life. METHODS: The study is a single-blinded randomised controlled trial. Participants are older adults, aged 67 or older, receiving home help services, who are able to walk with or without walking aids, who have experienced at least one fall during the last 12 months and who have a Mini Mental State Examination of 23 or above. The intervention group receives a programme, based on the Otago Exercise Programme, lasting 12 weeks including home visits and motivational telephone calls. The control group receives usual care. The primary outcome is health-related quality of life (SF-36). Secondary outcomes are leg strength, balance, walking speed, walking habits, activities of daily living, nutritional status and falls efficacy. All measurements are performed at baseline, following intervention at 3 months and at 6 months' follow-up. Sample size, based on the primary outcome, is set to 150 participants randomised into the two arms, including an estimated 15-20% drop out. Participants are recruited from six municipalities in Norway. DISCUSSION: This trial will generate new knowledge on the effects of an exercise falls prevention programme among older fallers receiving home help services. This knowledge will be useful for clinicians, for health managers in the primary health care service and for policy makers

    Should colorectal cancer screening start at the same age in European countries? Contributions from descriptive epidemiology

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    We assessed incidence and mortality of colorectal cancer (CRC) at various ages among women and men in 38 European countries. The ages at which defined levels of incidence and mortality were reached varied between 9 and 17 years between countries. This variation requires consideration in the definition of screening guidelines
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