Associations of sitting time with leisure-time physical inactivity,education, and body mass index change

We aimed to investigate the associations of long-term leisure-time physical inactivity, body mass index (BMI) change, and education with sitting time in a 35-year follow-up based on self-reports in surveys. Influences of working status in 2011 and familial confounding on the associations were tested. Data were based on the population-based Finnish Twin Cohort of 5232 twins (53-67-year-old, 41% men) with four surveys in 1975-2011. Statistical analyses were performed using linear regression with several covariates. The effect of familial confounding (genetics and shared environment) was analyzed using a co-twin control design which should be interpreted as if familial confounding plays a role, an association should be seen among all individuals but not in discordant twin pairs. Compared to those not at work, those at work had a longer total sitting time/d. For those at work, higher education was associated with more total sitting but with less non-work sitting. Long-term leisure-time physical inactivity was associated with more non-work sitting among those at work, whereas long-term weight gain with more total and non-work sitting regardless of working status. Familial confounding attenuated the associations, except for the association of increasing BMI with total and non-work sitting among women at work. To conclude, total sitting time was longer among those still at work, but it was also influenced by long-term leisure-time physical inactivity, higher education, and an increase of BMI over the years. Public health efforts should be targeted to reduce sedentary behavior by promoting life-long leisure-time physical activity and weight control.     

Exploration and Preparation of a Dose-Flexible Regulation System for Levetiracetam Tablets via Novel Semi-Solid Extrusion Three-Dimensional Printing

Levetiracetam therapy is often associated with high levels of individual variation in the recommended dose required to achieve preferential treatment. Thus, a reliable and dynamic regulation system to accurately tailor dose is necessary. The main objective of this study is to explore and prepare a dose-flexible control system suitable for rapid release tablets equipped with high drug loading and a cylindrical model design. Semi-solid extrusion 3-dimensional printing was utilized to fabricate a series of tablets of increased volume. This method was compatible with 3 patterns to regulate the volumes to manipulate the tablet mass and achieve tailored personalized precision dosing. All tablets from each pattern exhibited a smooth surface and regular shape, as well as sufficient mechanical strength. A good linear correlation between the mass and theoretical volume of the tablets was maintained, regardless of the pattern used. The range of dose accuracy was between 103.3% and 96.2%, with an acceptable variation coefficient in the range of 0.6%-3.2%. Faster release behavior for levetiracetam can be achieved from the small-sized tablets due to their larger surface area/mass ratio. All the results demonstrated the potential and capability of semi-solid extrusion 3-dimensional printing as a novel pharmaceutical manufacturing technique to provide a dynamic and highly accurate controllable system for preparing patient-tailored medicines.     

Neuro-protective potential of quercetin during chlorpyrifos induced neurotoxicity in rats

Chlorpyrifos (CPF) has been considered as one of the most potent organophosphates and is linked to several neurological disorders. On the other hand, Quercetin is a vital plant flavanoid and has been reported to regulate a number of physiological processes in the central nervous system. The present study was conducted to investigate the protective potential of quercetin during chlorpyrifos induced neurotoxicity. Female Wistar rats weighing 150–200?g were divided into four different groups viz: Normal control, CPF treated (13.5?mg/kg.b.wt. every alternate day), Quercetin treated (50?mg/kg.b.wt./day) and combined CPF and quercetin-treated. All the treatments were carried out for a total duration of eight weeks. Chlorpyrifos treatment showed significant alterations in the cognitive behavior and motor activities of rats, which were appreciably improved upon simultaneous supplementation with quercetin. Further, CPF treatment caused a significant inhibition in the enzyme activities of acetylcholinesterase and choline acetyltransferase, but caused an increase in the levels of acetylcholine in the brain. Further, chlorpyrifos exposure significantly elevated the levels of lipid peroxidation and protein carbonyl contents as well as the activities of catalase, superoxide dismutase, which were interestingly found to be decreased following co-treatment with quercetin. In contrast, CPF treatment decreased the activities of glutathione reductase, transferase, as well as levels of reduced and total glutathione in both the cerebrum and cerebellum but co-administration of quercetin, increased these levels. Chlorpyrifos treatment altered the neuro-histoarchitecture, which showed improvement upon quercetin supplementation. Hence, this study suggests that quercetin can be used as a prophylactic intervention to prevent CPF induced neurotoxicity.     

Meal frequency and timing in health and disease

Although major research efforts have focused on how specific components of foodstuffs affect health, relatively little is known about a more fundamental aspect of diet, the frequency and circadian timing of meals, and potential benefits of intermittent periods with no or very low energy intakes. The most common eating pattern in modern societies, three meals plus snacks every day, is abnormal from an evolutionary perspective. Emerging findings from studies of animal models and human subjects suggest that intermittent energy restriction periods of as little as 16 h can improve health indicators and counteract disease processes. The mechanisms involve a metabolic shift to fat metabolism and ketone production, and stimulation of adaptive cellular stress responses that prevent and repair molecular damage. As data on the optimal frequency and timing of meals crystalizes, it will be critical to develop strategies to incorporate those eating patterns into health care policy and practice, and the lifestyles of the population.     

Neural correlates of auditory streaming in an objective behavioral task

Segregating streams of sounds from sources in complex acoustic scenes is crucial for perception in real world situations. We analyzed an objective psychophysical measure of stream segregation obtained while simultaneously recording forebrain neurons in the European starlings to investigate neural correlates of segregating a stream of A tones from a stream of B tones presented at one-half the rate. The objective measure, sensitivity for time shift detection of the B tone, was higher when the A and B tones were of the same frequency (one stream) compared with when there was a 6- or 12-semitone difference between them (two streams). The sensitivity for representing time shifts in spiking patterns was correlated with the behavioral sensitivity. The spiking patterns reflected the stimulus characteristics but not the behavioral response, indicating that the birds’ primary cortical field represents the segregated streams, but not the decision process.In the natural environment, sounds produced by multiple sources must be segregated to retrieve the information that they convey. At the same time, sequential sound signals from an individual source must be integrated to perform the analysis. The auditory system of humans, as well as that of many vertebrate species, is able to parse signals from multiple sources into separate sets of “auditory streams” based on the signals’ spectral and/or temporal profiles (1–5). Attention affects auditory streaming, and imaging studies have shown that it modulates brain activity during the analysis of segregated streams of signals (6–13). Although to date most psychophysical and imaging studies on auditory streaming have investigated attentive, actively listening human subjects, animal studies have only investigated passively listening subjects not involved in a specific task requiring stream segregation (14–18). Better insight into the cellular mechanisms underlying auditory streaming can be gained by investigating neuronal responses in an actively listening animal.Here we present neuronal response data obtained from an actively listening bird, the European starling (Sturnus vulgaris), performing a task that has been shown in human subjects to be more easily mastered if signals are integrated into a single auditory stream rather than separated into two different streams (19–21). Behavioral performance in such tasks can serve as an objective measure for stream segregation, and correlated neuronal response measures can serve to elucidate the mechanisms underlying the perceptual effects. Behavioral responses indicating auditory stream segregation of pure tone sequences in the European starling have been reported previously (22). Because larger frequency differences lead to better stream segregation both in the physiological response and in perception in a similar way as in humans (16, 22), the European starling is a suitable animal model for studying the central processes involved in auditory scene analysis.We investigated the detection of irregular timing in a sequence of signals for which the auditory system is more sensitive if the signals are perceived as forming a single stream rather than being perceptually segregated into different streams (20, 21, 23, 24). We recorded multiunit activity in the songbird forebrain in an area (field L complex) that is homologous to the mammalian primary auditory cortex while presenting sequences of pure tone ABA- triplet stimuli (i.e., ABA-ABA-..., ref. 1). Neural responses were recorded while the bird behaviorally reported a shift in the temporal position of the B tone in the triplet. Based on psychophysical studies in humans, we expected shift detection thresholds to be smaller if the A and B tones were perceived as belonging to one stream rather than to two separate streams. Parallel measurements of neuronal responses and the bird’s perception, as reflected in behavioral responses, allowed us to correlate the sensitivity of the neuronal representation with behavioral sensitivity on a trial-by-trial basis. We applied a similar metric to perception and neuronal representation using signal detection theory and receiver operating characteristic (ROC) analysis. By comparing neuronal responses when the animal detected versus failed to detect a given time shift, we evaluated whether neural activity in the starling’s primary cortical area reflects the stimulus characteristics or whether it also indicates the bird’s perception, as evidenced by its behavioral decisions.     

Impact of school-based health promotion interventions aimed at different behavioral domains: a systematic review

Objective

Given that lifestyleshave similar determinants and that school-based interventions are usually targeted at all the risks that affect adolescents, the objective of this systematic review was to summarize the characteristics and effects of school-based interventions acting on different behavioral domains of adolescent health promotion.

Methods

The review process was conducted by two independent reviewers who searched PubMed, Scopus, PsycINFO, and ERIC databases for experimental or observational studies with at least two measures of results published from 2007 to 2011, given that the research information available doubles every 5 years. Methodological quality was assessed with a standardized tool.

Results

Information was extracted from 35 studies aiming to prevent risk behaviors and promote healthy nutrition, physical activity, and mental and holistic health. Activities were based on theoretical models and were classified into interactive lessons, peer mediation, environmental changes, parents’ and community activities, and tailored messages by computer-assisted training or other resources, usually including multiple components. In some cases, we identified some moderate to large, short- and long-term effects on behavioral and intermediate variable.

Conclusions

This exhaustive review found that well-implemented interventions can promote adolescent health. These findings are consistent with recent reviews. Implications for practice, public health, and research are discussed.     

青岛和丽水地区双生子研究：体育活动和静坐行为的遗传度

目的 探讨山东省青岛和浙江省丽水地区双生子人群体育活动和静坐行为的遗传度。方法 使用两地区2004 年随访的有卵型信息的双生子人群（共568 对,其中青岛242 对,丽水326 对）横断面调查资料,通过问卷调查得到体育活动和静坐行为信息。采用基于双生子的方差组分分析方法计算双生子表型的遗传度。结果 同卵双生子有367 对,异卵双生子有201 对,双生子中男性571 人,女性565 人。同卵双生子年龄为（41.14±10.11）岁,异卵双生子年龄为（41.23±9.89）岁。青岛和丽水地区＜40 岁人群的体育活动遗传度为78%（35%～96%）、59%（0～94%）,≥40 岁人群体育活动不受遗传影响。青岛和丽水地区静坐行为遗传度分别为68%（59%～75%）、32%（7%～62%）。结论 青岛和丽水地区人群静坐行为水平受遗传影响,且遗传因素在20～40 岁人群的体育活动水平中有着重要作用。