Duration of clinical symptoms in children under two years of age with acute otitis media

Objective: To describe the course of symptoms during the first ten days of episodes of AOM in children under two years of age.

Methods: Within the framework of a placebo-controlled, double-blind, randomised trial studying the effect of amoxicillin on acute otitis media in children under two years of age in the Netherlands, symptoms were recorded in diaries by the parents. Durations of symptoms were plotted by means of Kaplan-Meier curves. Possible factors influencing the duration were analysed in a Cox regression.

Results: Data from 230 children were used in the analyses. The median duration of fever was two days and the median duration of the combination of earache and/or crying was eight days. The duration of earache and/or crying was not influenced by any factor analysed (including treatment allocation).

Conclusion: Fifty per cent of the children under two years with an episode of AOM had symptoms for more than eight days (95% CI: 6.9-9.1). Since antibiotic treatment did not influence this period, persistence of symptoms should not be a reason for changing antibiotic therapy.     

The use of genetically modified mice in cancer risk assessment: Challenges and limitations

Abstract

The use of genetically modified (GM) mice to assess carcinogenicity is playing an increasingly important role in the safety evaluation of chemicals. While progress has been made in developing and evaluating mouse models such as the Trp53^+/?, Tg.AC and the rasH2, the suitability of these models as replacements for the conventional rodent cancer bioassay and for assessing human health risks remains uncertain. The objective of this research was to evaluate the use of accelerated cancer bioassays with GM mice for assessing the potential health risks associated with exposure to carcinogenic agents. We compared the published results from the GM bioassays to those obtained in the National Toxicology Program’s conventional chronic mouse bioassay for their potential use in risk assessment. Our analysis indicates that the GM models are less efficient in detecting carcinogenic agents but more consistent in identifying non-carcinogenic agents. We identified several issues of concern related to the design of the accelerated bioassays (e.g., sample size, study duration, genetic stability and reproducibility) as well as pathway-dependency of effects, and different carcinogenic mechanisms operable in GM and non-GM mice. The use of the GM models for dose-response assessment is particularly problematic as these models are, at times, much more or less sensitive than the conventional rodent cancer bioassays. Thus, the existing GM mouse models may be useful for hazard identification, but will be of limited use for dose-response assessment. Hence, caution should be exercised when using GM mouse models to assess the carcinogenic risks of chemicals.     

Perspective of parents and caregivers on the influence of full-time day-care attendance on young children

The aim of this study was to explore the experience of parents and caregivers regarding young children in day care. The tiredness of children after day-care attendance was explored. In the autumn of 2009, 41 parents and 35 caregivers of children aged 1.5 years or younger living in the city of Trondheim and nearby communities were assessed using a semi-structured qualitative interview. There was agreement among parents and caregivers that children became very tired after full-time care. In spite of the good quality of the care, with a relatively low child/adult ratio and very experienced caregivers with high educational qualifications, most children became very tired at the end of the stay. Tiredness in children also seemed to accumulate during the week and reached its peak on Fridays. The children adjusted well to care; however, they got very tired when the stay lasted a full day. Children who were picked up somewhat earlier did not exhibit the same level of tiredness.     

右室起搏电极参数随诊及其对心功能的影响

目的通过比较右室间隔部起搏和右室心尖部起搏电极参数和心功能的变化趋势，选择更为有利的起搏方式。方法选取心尖部起搏21例和间隔部起搏21例，术时、12个月、24个月随诊，分别作心脏彩色多普勒超声检查，记录左室舒张末期内径（LVEDD）、左室射血分数（LVEF）、起搏心电图测量Ⅱ导联QRS波时限、抽血查氨基末端脑钠肽前体（NT-proBNP）、起搏器程控仪记录阈值、阻抗、R波感知进行比较。结果间隔部组比心尖部组QRS时限和电极阻抗小，随起搏时间延长QRS时限、NT-proBNP、LVEDD增加、LVEF（％）下降，心尖部组表现较为明显。结论间隔部起搏QRS波较窄，LVEF（％）下降缓慢、LVEDD（mm）和NT-proBNP（pg／m1）升高缓慢，与心尖部起搏比较，心室同步性好、可延缓心功能减退，是右室起搏较好的选择部位。     

Enhancing the Reliability in the Noninvasive Measurement of the His Bundle Magnetic Field Using a Novel Signal Averaging Methodology

Background: Extraction of the weak electrical activity of the “His Bundle” (HB) by noninvasive methods has not been very successful in the past. The study reassesses the use of signal averaged magnetocardiography (SAMCG), overcoming some of the limitations in earlier studies including in the signal averaging methodology. Methods: SAMCG on healthy subjects (14 male and 1 female) were performed using R‐peak as the fiducial point in all cases and also using QRS‐onset as the fiducial point in select cases. Results: A conspicuous feature (H) with a magnitude up to 200 femto Tesla (fT) attributed to the HB activity was observed in the PR segment at several spatial positions on the thorax, with onset at 35–50 ms before the QRS‐onset (V) in 15 out of 18 trials constituting 83% of cases studied. The QRS‐onset as the fiducial point resolved the feature better compared to the conventionally used R‐peak, especially in trials exhibiting spread in heart rate (HR). This is attributed to the fluctuations in Q_onRD (the time interval between QRS‐onset and R‐peak) compared to the temporal stability of the H‐V duration. Conclusions: SAMCG reveals a well‐resolved H feature. The double hump morphology of the feature extended at least up to a frequency of 150 Hz. The importance of the choice of QRS‐onset as the fiducial point is unequivocally demonstrated, illustrated by measurements on subjects exhibiting considerable heart rate variability. The latter has a general validity and should be applicable to SAECG as well.     

Predictors of sleep disturbances in the first year of life: a longitudinal study

ObjectiveThe aim of this study was to identify early predictors of nocturnal awakenings and short sleep duration during the first year of life, in terms of sleep habits and patterns. We also analyzed the trend of nocturnal awakenings and total sleep duration from 3 to 12 months of age.MethodsThe parents of 704 infants (49.3% female) were interviewed during their first year of life. The interview included questions on infant sleep (eg, sleep habits, sleep duration, number of nocturnal awakenings) and maternal perception of infant sleep difficulties.ResultsThe study results indicate that most of the infants at risk, with three or more nocturnal awakenings or ≤10 h of total sleep duration in the early months of life, tend to display a similar pattern of sleep problems at 12 months. The main early predictors of sleep problems at 12 months were sleep duration, sleep initiation method, and nocturnal awakenings. More specifically, infants with three or more nocturnal awakenings or ≤10 h of total sleep duration at 12 months were those with a higher number of awakenings during the night and a shorter sleep duration, at both three and six months. In addition, infants at risk for sleep problems at 12 months had an independent sleep initiation method at three months, whereas these same infants had a nonindependent sleep initiation method at six months.ConclusionsOur study identified the early predictors of sleep problems at 12 months. Caregivers should identify these early symptoms in infants to prevent possible sleep difficulties in later years.     

Association of sleep duration and incidence of diabetes modified by tea consumption: a report from the Shanghai men's health study

ObjectivesTo evaluate the association between sleep duration and the incidence of diabetes stratified by sleep-related factors among Chinese men.MethodsThis study included 34,825 men who provided information on sleep-related questions in the Shanghai Men's Health Study, a population-based cohort study conducted in Shanghai, China from 2002 to 2011. Participants were excluded who had a history of diabetes or who were diagnosed with diabetes within 2 years of recruitment. Cox regression was employed to evaluate the influence of sleep duration and its interaction with sleep-related factors on diabetes risk.ResultsA total of 1521 incident cases were documented during a median of 5.6 follow-up years. Adjusted hazard ratios and 95% confidence intervals were 1.0 (0.9–1.1) and 1.2 (1.0–1.3) for men who slept <7 and ≥8 h per day, respectively, compared with those who slept 7 h per day (p_trend = 0.01). Stratified analyses revealed that the association between sleep duration and risk of diabetes was only statistically significant among current smokers and regular drinkers, never tea drinkers, men with a high body mass index, hypertension or comorbidity, and men who did not work nightshift or who snored. A statistically significant interaction between tea drinking and sleep duration was observed (p_interaction = 0.01). The above association patterns remained when daytime nappers were excluded from the analyses.ConclusionsThe data suggested that longer sleep duration, particularly among individuals already exhibiting factors linked to poor quality of sleep, was associated with diabetes. The association between sleep duration and diabetes may be modified by tea drinking, especially in older men or men with more sleep-related factors.