饮水负荷试验测定胃感觉的临床研究

目的　建立简便易行、非侵入性、符合胃肠生理的检测胃感觉阈值的诊断方法。方法用饮水负荷试验和电子恒压器法分别对 15例健康自愿者和 30例功能性消化不良患者的胃感知和不适阈值进行测定 ,以了解饮水负荷试验测定胃感觉阈值的敏感性、特异性、Kappa值、符合率 ,以及二者之间有无相关性。结果　与电子恒压器法相比较 ,饮水负荷试验测定胃感知阈值的敏感性为85 7% ,特异性为 93 5 % ,Kappa值为 0 82 ,二者的符合率为 91 1% ,两种方法所测得的结果也具有良好的相关性 (P <0 0 1)。饮水负荷试验测定胃不适阈值的敏感性为 81 8% ,特异性为 91 2 % ,Kappa值为 0 79,二者的符合率为 88 9% ,两种方法所测得的结果也具有良好的相关性 (P <0 0 1)。结论　与电子恒压器相比 ,饮水负荷试验测定胃感觉阈值具有较高的特异性、Kappa值和符合率 ,以及良好的相关性 ,可用于消化不良患者胃感觉功能临床辅助诊断和初筛检查 ,在基层医院有广泛的应用前景。     

激素释放心房电极的临床应用评价

对１１９例应用激素释放电极及９６例应用非激素释放电极患者在心房电极植入后即刻及术后１，３，６，１２，１８个月分别测试心房起搏阈值，并进行比较。发现激素释放心房电极的心房起搏阈值均显著低于非激素释放电极，且无非激素释放电极的早期阈值升高现象。植入激素释放心房电极９５％的患者在术后第３个月心房起搏阈值≤１．３Ｖ；植入非激素释放电极的患者心房起搏阈值≤１．３Ｖ者仅占１５％。表明激素释放心房电极明显优于非激素释放电极，即使进行长期低能量起搏前者亦非常安全，故能降低起搏器电池消耗和延长其寿命。     

Cost-sparing effect of twice-weekly targeted endurance training in type 2 diabetics: a one-year controlled randomized trial

OBJECTIVE: We evaluated the effects of targeted, moderate endurance training on healthcare cost, body composition and fitness in type 2 diabetes patients routinely followed within the French healthcare system. DESIGN AND METHODS: A total of 25 type 2 diabetic patients was randomly assigned to one of two groups: 13 underwent a training programme (eight sessions, followed by training twice a week for 30-45 minutes at home at the level of the ventilatory threshold [V(T)]); and 12 received their usual routine treatment. Both groups were followed for one year to evaluate healthcare costs, exercise effectiveness and a six-minute walking test. RESULTS: The training prevented loss of maximum aerobic capacity, which decreased slightly in the untrained group (P=0.014), and resulted in a higher maximum power output (P=0.041) and six-minute walking distance (P=0.020). The Voorrips activity score correlated with both V(O2max) (r=0.422, P<0.05) and six-minute walking distance (r=0.446, P<0.05). Changes in V(O2max) were negatively correlated with changes in body weight (r=0.608, P<0.01). Training decreased the insulin-resistance index (HOMA-IR) by 26% (P<0.05). Changes in percentages of fat were correlated to changes in waist circumference (r=0.436, P<0.05). The total healthcare cost was reduced by 50% in the trained group (euro 1.65+/-1 per day versus euro 3.00+/-1.47 per day in the untrained group; P<0.02) due to fewer hospitalizations (P=0.05) and less use of sulphonylureas (P<0.05). CONCLUSION: Endurance training at V(T) level prevented the decline in aerobic working capacity seen in untrained diabetics over the study period, and resulted in a marked reduction in healthcare costs due to less treatments and fewer hospitalizations.     

心房起搏阈值的随访分析

对３３例植入心房电极者进行起搏阈值的随访，结果表明：起搏阈值峰值为１．４４±０．７４Ｖ／０．５ｍｓ，出现在植入后两周内；慢性期起搏阈值为１．２２±０．４０Ｖ／０．５ｍｓ；伴器质性心脏病患者慢性期起搏阈值（１．７０士０．３７Ｖ／０．５ｍｓ）明显高于不伴器质性心脏病者（１．１６±０．３７Ｖ／０．５ｍｓ），Ｐ＜０．０１；激素电极的起搏阈值峰值（１．１２±０．２９Ｖ／０．５ｍｓ）和慢性期起搏阈值（０．７７±０．１７Ｖ／０．５ｍｓ）均显著低于非激素电极（１．８０±０．６８Ｖ／０．５ｍｓ和１．４０±０．３３Ｖ／０．５ｍｓ），Ｐ＜０．０５及０．００１。提出在非特殊情况下，将出厂时的电能由５．０Ｖ／０．５ｍｓ降至２．５Ｖ／０．５ｍｓ既可保证有效起搏，又可节省电能，从而延长起搏器的使用寿命。     

Multi-level basis selection of wavelet packet decomposition tree for heart sound classification

Wavelet packet transform decomposes a signal into a set of orthonormal bases (nodes) and provides opportunities to select an appropriate set of these bases for feature extraction. In this paper, multi-level basis selection (MLBS) is proposed to preserve the most informative bases of a wavelet packet decomposition tree through removing less informative bases by applying three exclusion criteria: frequency range, noise frequency, and energy threshold. MLBS achieved an accuracy of 97.56% for classifying normal heart sound, aortic stenosis, mitral regurgitation, and aortic regurgitation. MLBS is a promising basis selection to be suggested for signals with a small range of frequencies.     

Physiology of handcycling: A current sports perspective

Handcycling is a mode of mobility, and sport format within Para‐cycling, for those with a lower limb impairment. The exercise modality has been researched extensively in the rehabilitation setting. However, there is an emerging body of evidence detailing the physiological responses to handcycling in the competitive sport domain. Competitive handcyclists utilize equipment that is vastly disparate to that used for rehabilitation or recreation. Furthermore, the transferability of findings from early handcycling research to current international athletes regarding physiological profiles is severely limited. This narrative review aims to map the landscape within handcycling research and document the growing interest at the elite end of the exercise spectrum. From 58 experimental/case studies and four doctoral theses, we provide accounts of the aerobic capacity of handcyclists and the influence training status plays; present research regarding the physiological responses to handcycling performance, including tests of sprint performance; and discuss the finite information on handcyclists’ training habits and efficacy of bespoke interventions. Furthermore, given the wide variety of protocols employed and participants recruited previously, we present considerations for the interpretation of existing research and recommendations for future work, all with a focus on competitive sport. The majority of studies (n = 21) reported aerobic capacity, detailing peak rates of oxygen uptake and power output, with values >3.0 L min^?1 and 240 W shown in trained, male H3‐H4 classification athletes. Knowledge, though, is lacking for other classifications and female athletes. Similarly, little research is available concerning sprint performance with only one from eight studies recruiting athletes with an impairment.     

Altered modulation of gamma oscillation frequency by speed of visual motion in children with autism spectrum disorders

Background

Recent studies link autism spectrum disorders (ASD) with an altered balance between excitation and inhibition (E/I balance) in cortical networks. The brain oscillations in high gamma-band (50–120 Hz) are sensitive to the E/I balance and may appear useful biomarkers of certain ASD subtypes. The frequency of gamma oscillations is mediated by level of excitation of the fast-spiking inhibitory basket cells recruited by increasing strength of excitatory input. Therefore, the experimental manipulations affecting gamma frequency may throw light on inhibitory networks dysfunction in ASD.

Methods

Here, we used magnetoencephalography (MEG) to investigate modulation of visual gamma oscillation frequency by speed of drifting annular gratings (1.2, 3.6, 6.0 °/s) in 21 boys with ASD and 26 typically developing boys aged 7–15 years. Multitaper method was used for analysis of spectra of gamma power change upon stimulus presentation and permutation test was applied for statistical comparisons. We also assessed in our participants visual orientation discrimination thresholds, which are thought to depend on excitability of inhibitory networks in the visual cortex.

Results

Although frequency of the oscillatory gamma response increased with increasing velocity of visual motion in both groups of participants, the velocity effect was reduced in a substantial proportion of children with ASD. The range of velocity-related gamma frequency modulation correlated inversely with the ability to discriminate oblique line orientation in the ASD group, while no such correlation has been observed in the group of typically developing participants.

Conclusions

Our findings suggest that abnormal velocity-related gamma frequency modulation in ASD may constitute a potential biomarker for reduced excitability of fast-spiking inhibitory neurons in a subset of children with ASD.

Electronic supplementary material

The online version of this article (doi:10.1186/s11689-015-9121-x) contains supplementary material, which is available to authorized users.     

Season, fever prevalence and pyrogenic threshold for malaria disease definition in an endemic area of Mali

BACKGROUND: Modelling malaria parasitaemia as function of fever has been proposed as best alternative to estimate the attributable fraction of malaria fever and the sensitivity and specificity of different case definitions of malaria disease. OBJECTIVES: To determine the prevalence of fever and its relation to malaria parasitaemia and to establish a pyrogenic threshold for malaria disease in the area. METHODS: We conducted two cross-sectional surveys in children of 6 months to 9 years of age (2434 during the rainy season of 1993 and 2353 during the dry season of 1994) randomly selected from 21 areas of Bandiagara district, Mali. RESULTS: The relationship between fever and Plasmodium falciparum parasitaemia depends strongly on the season, thus affecting the malaria-attributable fraction of fever cases and the sensitivity and specificity of malaria case definitions. The overall proportion of fever attributable to malaria parasitaemia was 33.6% during the rainy season and 23.3% during the dry season, with the highest proportion occurring among the youngest children. The cut-off value, where the sensitivity curve crosses the specificity curve, was around 3200 pf/microl for all age categories during the rainy season and 200 pf/microl during the dry season. CONCLUSIONS: Malaria remains a main cause of fever in this area of Mali. The pyrogenic threshold of parasitaemia depends strongly on the season, and different cut-off levels of parasitaemia should be used during the two seasons to define malaria cases in this area.