BACKGROUND & AIMS: BACKGROUND:Trabecular bone strength diminishes as a result of osteoporosis and altered biomechanical loading at the vertebral and spinal levels. The spine consists of the anterior, middle and posterior columns and the load supported by the anterior and middle columns will differ across different regions of the spine. Stress shielding of the anterior column can contribute to bone loss and increase the risk of wedge fracture. There is a lack of quantitative data related to regional spinal bone mineral density distribution over time. We hypothesize that there is an increase in the posterior-to-anterior vertebral body bone mineral density ratio and a decrease in whole-body bone mineral density over time. METHODS:Bone mineral density was measured in 33 subjects using quantitative computed tomography scans for L1-L3 vertebrae, region (anterior and posterior vertebral body), and time (baseline and 6 years after). FINDINGS:Lumbar bone mineral density decreased significantly (Δ: ~15%) from baseline to the 6th year visit. Individual vertebra differences over time (L1: ~14%, L2: ~14%, L3: ~17%) showed statistical significance. Anterior bone mineral density change was significantly greater than in the posterior vertebral body region (Δ anterior: ~18%; Δ posterior: ~13%). Posterior-to-anterior bone mineral density ratio was significantly greater in the 6th year compared to baseline values (mean (SD), 1.33 (0.2) vs. 1.23 (0.1)). INTERPRETATION:This study provides longitudinal quantitative measurement of bone mineral density in vertebrae as well as regional changes in the anterior and posterior regions. Understanding bone mineral density distribution over time may help to decrease the risk of wedge fractures if interventions can be developed to bring spine loading to its normal state.

背景与目标：

BACKGROUND & AIMS: :We investigated the ability of systolic and diastolic carotid artery longitudinal wall motion (CALM) to delineate expected differences in arterial health in individuals representing a range of both age and health status. We recruited 161 younger healthy adults (aged 24 ± 5 y), 51 older healthy adults (aged 70 ± 5 y) and 14 adults with coronary artery disease (aged 67 ± 8 y) for resting assessment of CALM and arterial stiffness. All CALM parameters were reduced in the old healthy adults and adults with coronary artery disease compared with the young healthy adults (p < 0.01), with diastolic velocity and maximum diastolic acceleration being further reduced in the adults with coronary artery disease than in the older healthy adults (p < 0.01). Diastolic CALM parameters were more strongly related to age (β range: -0.46 to -0.53) than systolic CALM parameters (β range: -0.24 to -0.44). In contrast to previous examinations of a variety of CALM parameters, diastolic CALM may provide superior promise in terms of characterizing arterial wall properties, with additional sensitivity to cardiovascular disease status.

背景与目标： : 我们研究了收缩期和舒张期颈动脉纵向壁运动 (CALM) 描绘代表年龄和健康状况范围的个体的动脉健康预期差异的能力。我们招募了161名年轻的健康成年人 (24 ± 5岁)，51名老年健康成年人 (70 ± 5岁) 和14名患有冠状动脉疾病的成年人 (67 ± 8岁) 进行静息评估平静和动脉僵硬度。与年轻健康成年人相比，老年健康成年人和患有冠状动脉疾病的成年人的所有CALM参数均降低 (p <0.01)，与老年健康成年人相比，患有冠状动脉疾病的成年人的舒张速度和最大舒张加速度进一步降低 (p <0.01)。舒张期平静参数与年龄 (β 范围: -0.46至-0.53) 的相关性高于收缩期平静参数 (β 范围: -0.24至-0.44)。与以前对各种平静参数的检查相比，舒张期平静在表征动脉壁特性方面可能具有出色的前景，并且对心血管疾病状态具有额外的敏感性。

BACKGROUND & AIMS: OBJECTIVE:To investigate: (1) the course of coronary heart disease risk factors (lipid profiles and body mass index (BMI)) in the first five years after discharge from inpatient spinal cord injury (SCI) rehabilitation and (2) the association between lifestyle (physical activity, self-care related to fitness, smoking, alcohol, body mass and low-fat diet) and coronary heart disease risk factors during that period. DESIGN:Prospective cohort study. PARTICIPANTS/METHODS:Individuals with SCI (N=130). Total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG) and BMI were determined at discharge from inpatient rehabilitation and 1 and 5 years after discharge. Using multilevel regression models, the effects of lifestyle (drinking alcohol, smoking, active lifestyle and self-care) on the lipid profiles and BMI were determined. RESULTS:After correction for lesion and personal characteristics, no changes in lipid profiles in the five years after discharge were seen, whereas the BMI increased significantly with 1.8 kg m(-2). A high percentage was at risk of cardiovascular disease due to high BMI (63-75%) or HDL (66-95%). The individuals who indicated to maintain their fitness level as good as possible and the individuals with a low BMI showed better lipid profiles. Individuals with a more active lifestyle showed higher HDL levels. Individuals who avoid smoking showed a 1.5 kg m(-2) higher BMI. CONCLUSION:Lipid profiles seem to stabilize in the years after discharge from inpatient SCI rehabilitation, whereas the BMI increased. Lifestyle factors associated with a favorable lipid profile and BMI could be identified.

背景与目标：

BACKGROUND & AIMS: OBJECTIVE:To examine the relative contribution of hyperactivity, conduct, and emotional problems in predicting criminal offending. METHOD:In all, 173 boys aged 6 to 8 years (assessed for hyperactivity, conduct, and emotional problems) were followed up 19 years later by examining criminal offense histories. RESULTS:Significant main effects for total and violent convictions were found, the strongest being for violent criminal offenses. Conduct problems predicted general offending (irrespective of the type of conviction), whereas emotional problems were the single best predictor of violent convictions. Hyperactivity was not a significant predictor in the models. CONCLUSION:The findings provide insight into the developmental mechanisms that mediate criminal behavior by showing that childhood emotional problems independently contribute to the risk of violent offending in later life.

背景与目标：

BACKGROUND & AIMS: OBJECTIVE:Acute stress reactions (ASR) and postpartum depressive symptoms (PDS) are frequent after childbirth. The present study addresses the change and overlap of ASR and PDS from the 1- to 3-week postpartum and examines the interplay of caregiver support and subjective birth experience with regard to the development of ASR/PDS within a longitudinal path model. METHOD:A total of 219 mothers completed questionnaires about caregiver support and subjective birth experience (Salmon's Item List) at 48-6-h postpartum. ASR and PDS were measured for 1- and 3-week postpartum. The Impact of Event Scale (IES) was used to assess ASR, and the Edinburgh Postnatal Depression Scale (EPDS) was used to assess PDS. RESULTS:ASR was frequent 1-week postpartum (44.7%) and declined till week 3 (24.8%, p <.001), while the prevalence of PDS was continuous (14.2% week 1; 12.6% week 3; p = .380). Favorable reports of caregiver support were related to better subjective childbirth experience, which was related to lower ASR and PDS (controlled for age, mode of delivery, parity, EDA and duration of childbirth). CONCLUSION:High quality of intrapartum care and positive birth experiences facilitate psychological adjustment in the first 3-week postpartum.

背景与目标：

BACKGROUND & AIMS: BACKGROUND:Predicted maturity offset and age at peak height velocity are increasingly used with youth athletes, although validation studies of the equations indicated major limitations. The equations have since been modified and simplified. OBJECTIVE:The objective of this study was to validate the new maturity offset prediction equations in independent longitudinal samples of boys and girls. METHODS:Two new equations for boys with chronological age and sitting height and chronological age and stature as predictors, and one equation for girls with chronological age and stature as predictors were evaluated in serial data from the Wrocław Growth Study, 193 boys (aged 8-18 years) and 198 girls (aged 8-16 years). Observed age at peak height velocity for each youth was estimated with the Preece-Baines Model 1. The original prediction equations were included for comparison. Predicted age at peak height velocity was the difference between chronological age at prediction and maturity offset. RESULTS:Predicted ages at peak height velocity with the new equations approximated observed ages at peak height velocity in average maturing boys near the time of peak height velocity; a corresponding window for average maturing girls was not apparent. Compared with observed age at peak height velocity, predicted ages at peak height velocity with the new and original equations were consistently later in early maturing youth and earlier in late maturing youth of both sexes. Predicted ages at peak height velocity with the new equations had reduced variation compared with the original equations and especially observed ages at peak height velocity. Intra-individual variation in predicted ages at peak height velocity with all equations was considerable. CONCLUSION:The new equations are useful for average maturing boys close to the time of peak height velocity; there does not appear to be a clear window for average maturing girls. The new and original equations have major limitations with early and late maturing boys and girls.

背景与目标：

BACKGROUND & AIMS: BACKGROUND:Older people constitute a significant proportion of the total population and their number is projected to increase by more than half by 2030. This increasing probability of late survival comes with considerable individual, economic and social impact. Physical activity (PA) can influence the ageing process but the specific relationship with healthy ageing (HA) is unclear. METHODS:We conducted a systematic review and meta-analysis of longitudinal studies examining the associations of PA with HA. Studies were identified from a systematic search across major electronic databases from inception as January 2017. Random-effect meta-analysis was performed to calculate a pooled effect size (ES) and 95% CIs. Studies were assessed for methodological quality. RESULTS:Overall, 23 studies were identified including 174,114 participants (30% men) with age ranges from 20 to 87 years old. There was considerable heterogeneity in the definition and measurement of HA and PA. Most of the identified studies reported a significant positive association of PA with HA, six reported a non-significant. Meta-analysis revealed that PA is positively associated with HA (ES: 1.39, 95% CI=1.23-1.57, n=17) even if adjusted for publication bias (ES: 1.27, 95% CI=1.11-1.45, n=20). CONCLUSIONS:There is consistent evidence from longitudinal observational studies that PA is positively associated with HA, regardless of definition and measurement. Future research should focus on the implementation of a single metric of HA, on the use of objective measures for PA assessment and on a full-range of confounding adjustment. In addition, our research indicated the limited research on ageing in low-and-middle income countries.

背景与目标：

BACKGROUND & AIMS: OBJECTIVES:To examine the mental health of unaccompanied refugee minors prospectively during the asylum-seeking process, with a focus on specific stages in the asylum process, such as age assessment, placement in a supportive or non-supportive facility and final decision on the asylum applications. DESIGN:This was a2½ year follow-up study of unaccompanied minors (UM) seeking asylum in Norway. Data were collected within three weeks (n=138) and at 4 months (n=101), 15 months (n=84) and 26 months (n=69) after arrival. SETTING:Initially in an observation and orientation centre for unaccompanied asylum-seeking adolescents, and subsequently wherever the UM were located in other refugee facilities in Norway. PARTICIPANTS:Male UM from Afghanistan, Somalia, Algeria and Iran. MAIN OUTCOME MEASURES:Mental health symptoms assessed by Hopkins Symptom Checklist-25 and Harvard Trauma Questionnaire. RESULTS:At the group level, the young asylum seekers reported high levels of psychological distress on arrival and symptom levels that stayed relatively unchanged over time. According to age-assessment procedures, 56% of the population were not recognised as minors. Subsequent placement in a low-support facility was associated with higher levels of psychological distress in the follow-up period. Those who were placed in a reception centre for adults had higher levels of psychological distress symptoms both after 15 months and 26 months compared with the remaining participants who were placed in reception centres for youth. Refusal of asylum was highly associated with higher levels of psychological distress. CONCLUSION:Mental health trajectory of young asylum seekers appears to be negatively affected by low support and refusal of asylum.

背景与目标：

BACKGROUND & AIMS: OBJECTIVE:We determined the longitudinal association of glucose metabolism with retinopathy in a sample of the Australian population. RESEARCH DESIGN AND METHODS:The Australian Diabetes Obesity and Lifestyle (AusDiab) study is a national, longitudinal study of adults aged > or =25 years from 42 randomly selected areas of Australia. Retinopathy was assessed at baseline in 1999-2000 and 5 years later in 2004-2005 in participants identified as having diabetes (based on self-report and oral glucose tolerance test) and impaired glucose metabolism and in a random sample with normal glucose tolerance. Complete retinal data were available for 1,192 participants. Photographs were graded at two time points according to a simplified version of the Wisconsin grading system. RESULTS:The 5-year incidences of retinopathy were 13.9 and 3.0% among those with known and newly diagnosed diabetes at baseline, respectively. Of those who developed incident newly diagnosed diabetes at follow-up, 11.9% had retinopathy at baseline compared with 5.6% of those who did not progress to incident newly diagnosed diabetes (P = 0.037). After adjustment for factors identified as risk factors for diabetes, individuals with retinopathy signs at baseline were twice as likely to develop incident newly diagnosed diabetes compared with those who did not have retinopathy signs at baseline. CONCLUSIONS:The 5-year incidence of retinopathy was 13.9% among individuals with known diabetes. Nondiabetic individuals with retinopathy signs at baseline had a twofold higher risk of developing incident newly diagnosed diabetes 5 years later. This result provides further evidence that mild retinopathy signs may be a preclinical marker of underlying microvascular disease and future diabetes risk.

背景与目标：

BACKGROUND & AIMS: :A mathematical model is presented to study the motion of the spermatozoa in the cervical canal by considering the transverse waves along its tail and the transverse and longitudinal motions of the cervical wall. In an attempt to control fertility by reducing the speed of sperm, the transverse waves have been considered in the direction opposite to the motion of the spermatozoa. It has been shown that by having appropriate transverse wave motion and longitudinal velocity, the sperm may not be able to move towards the oviduct even if it could continue to have its own propelling velocity. A particular case of the motion of a thin plane sheet in a channel under peristaltic motion of its walls has also been obtained and studied.

背景与目标： : 提出了一个数学模型，通过考虑沿其尾部的横波以及子宫颈壁的横向和纵向运动来研究精子在子宫颈管内的运动。为了通过降低精子的速度来控制生育能力，已将横波视为与精子运动相反的方向。已经表明，通过具有适当的横波运动和纵向速度，即使精子可以继续具有自己的推进速度，也可能无法向输卵管移动。还获得并研究了薄平面在通道壁蠕动下在通道中运动的特殊情况。

BACKGROUND & AIMS: OBJECTIVES:To longitudinally assess the receptive and expressive language functioning of children with symptomatic HIV disease and to explore the relationship between immune status, computed tomography (CT) brain scan abnormalities, and language dysfunction over time. METHODS:Children with symptomatic HIV infection were administered an age-appropriate standardized comprehensive language test and general cognitive measure prior to starting antiretroviral therapy (n = 44) and again after 6 months (n = 29) and 24 months (n = 17). CD4 percentage and CT brain scans were also obtained at each evaluation. RESULTS:Expressive language was significantly more impaired than receptive language at the baseline, 6- and 24-month evaluations. No significant changes over time were found in receptive or expressive language from baseline to after 6 months of antiretroviral therapy, but despite treatment, language scores declined significantly between 6 and 24 months. Overall cognitive function, however, remained stable from baseline to 24 months. Age-adjusted CD4 percentage increased significantly over the initial 6 months, then remained stable. Overall CT brain scan severity ratings did not change significantly over 24 months. CONCLUSION:Expressive language was consistently more impaired than receptive language over 24 months, further supporting an earlier finding that expressive language was differentially affected by HIV in children with symptomatic disease. Both receptive and expressive language declined significantly after 24 months despite antiretroviral therapy, although overall cognitive function remained stable. Thus, functioning in some domains may be more vulnerable to the effects of HIV and global measures of cognitive ability may mask such differential changes in specific brain functions.

背景与目标：

BACKGROUND & AIMS: BACKGROUND:To examine dementia characteristics, age at onset and associated comorbidities in persons with Down syndrome. METHOD:Seventy-seven people with Down syndrome aged 35 years and older were followed longitudinally. The diagnosis of dementia was established using the modified International Classification of Diseases, Tenth Revision (ICD-10) criteria and a combination of objective and informant-based tests. Cognitive tests included the Test for Severe Impairment and the Down Syndrome Mental Status Examination; adaptive behaviour was measured using the Daily Living Skills Questionnaire. The Dementia Questionnaire for Mental Retarded Persons (DMR) was added to the test battery in 2005 and this study includes follow-up data for this instrument. RESULTS:Over the 14-year period the average age of diagnosis at 55.41 years (SD = 7.14) was in the higher range of previously reported estimates (51-56 years) and a median survival of 7 years after diagnosis. Persons with dementia in the sample were significantly older than persons without dementia. The presence of dementia was also associated with epilepsy and sensory impairments. Among instruments the DMR appeared most sensitive to tracking change in symptoms over time before diagnosis. CONCLUSION:The previously reported high risk levels for dementia among people with Down syndrome was confirmed in these data as was the value of the instruments utilised in tracking decline and helping to confirm diagnosis even in persons with severe intellectual disability.

背景与目标：

BACKGROUND & AIMS: BACKGROUND/OBJECTIVE:Anxiety is common in patients experiencing neurocritical illness and their family caregivers. Resilience factors like mindfulness and coping skills may be protective against symptoms of emotional distress, including anxiety. Less is known about the interplay of anxiety symptoms and resilience factors between patients and caregivers. The purpose of this study is to examine the trajectory of anxiety symptoms among dyads of neurocritical care patients without major cognitive impairment and their family caregivers and to elucidate the relationship between resiliency (e.g., mindfulness and coping) and anxiety in these dyads. METHODS:Prospective, longitudinal study of adults admitted to the neurological intensive care unit (Neuro-ICU) and their caregivers. Dyads of patients (N = 102) and family caregivers (N = 103) completed self-report measures of mindfulness (Cognitive Affective Mindfulness Scale-Revised) and coping (Measure of Current Status-Part A) during Neuro-ICU hospitalization and anxiety symptoms (anxiety subscale of the Hospital Anxiety and Depression Scale) during hospitalization and at 3- and 6-month follow-up. We used actor-partner interdependence modeling to predict the effect of one's own baseline characteristics on one's own and one's partner's future anxiety symptoms. RESULTS:Rates of clinically significant anxiety symptoms were 40% for patients and 42% for caregivers at baseline. Of these, 20% of patients and 23% of caregivers showed moderate and severe symptoms. Approximately, one-third of patients and caregivers reported clinically significant anxiety symptoms at 3- and 6-month follow-ups, with more than 20% endorsing moderate or severe symptoms. Patients' own baseline mindfulness, coping, and anxiety symptoms were associated with lower anxiety symptoms at all time points (ps < 0.001)-this was also true for caregivers. For both patients and caregivers, one's own baseline mindfulness predicted their partner's anxiety symptoms 3 months later (p = 0.008), but not at 6-month follow-up. CONCLUSIONS:Anxiety symptoms in Neuro-ICU patient-caregiver dyads are high through 6 months following admission. Mindfulness is interdependent and protective against anxiety in dyads at 3-month but not 6-month follow-up. Early, dyad-based interventions may prevent the development of chronic anxiety in patients without major cognitive impairment and caregivers.

背景与目标：

BACKGROUND & AIMS: :The aim of this prospective cohort study was to investigate the association between intrauterine fetal growth patterns and periodontal status in pregnant women. Fifty-three pregnant women were recruited. Periodontitis was diagnosed based on probing pocket depth and clinical attachment level. Maternal urinary 8-hydroxy-2'-deoxyguanosine levels and body mass index were recorded. Ultrasonographic measurements of the biparietal diameter (BPD), abdominal circumference (AC), and femur length (FL) were recorded, and estimated fetal weight (EFW) was calculated. In addition, approximation spline curves of BPD, AC, FL, and EFW were obtained throughout the gestation period. Recorded delivery outcomes were gestational age (GA), birth weight and length, sex, placental weight, and umbilical cord length. Forty-four participants (34.1 ± 4.9 years) were analyzed. Mean neonatal birth weight was 2906.0 ± 544.4 g. On multiple regression analysis, birth weight was related with periodontitis (standardized β = -0.21, P = 0.001). For EFW and BPD, the curves of the periodontitis group were located lower than those of the non-periodontitis group, with significant differences after 32 weeks and 20 weeks of GA, respectively. In conclusion, periodontal treatment before conception may be recommended and a good periodontal condition in the early stage of pregnancy at the latest is desirable for infant growth.

背景与目标： : 这项前瞻性队列研究的目的是调查孕妇宫内胎儿生长模式与牙周状况之间的关系。招募了53名孕妇。根据探查袋深度和临床依附水平诊断牙周炎。记录孕妇尿8-羟基-2 '-脱氧鸟苷水平和体重指数。记录双顶径 (BPD)，腹围 (AC) 和股骨长度 (FL) 的超声检查，并计算估计的胎儿体重 (EFW)。此外，在整个妊娠期获得了BPD，AC，FL和EFW的近似样条曲线。记录的分娩结局包括胎龄 (GA)，出生体重和身长，性别，胎盘重量和脐带长度。分析了44名参与者 (34.1   ±   4.9岁)。新生儿平均出生体重2906.0   ±   544.4  g。多元回归分析显示，出生体重与牙周炎相关 (标准化 β   =  -0.21，p   =   0.001)。对于EFW和BPD，牙周炎组的曲线低于非牙周炎组，分别在GA 32周和20周后具有显着差异。总之，建议在怀孕前进行牙周治疗，并且最晚在怀孕初期获得良好的牙周状况对于婴儿生长是可取的。

BACKGROUND & AIMS: :Regression calibration provides a way to obtain unbiased estimators of fixed effects in regression models when one or more predictors are measured with error. Recent development of measurement error methods has focused on models that include interaction terms between measured-with-error predictors, and separately, methods for estimation in models that account for correlated data. In this work, we derive explicit and novel forms of regression calibration estimators and associated asymptotic variances for longitudinal models that include interaction terms, when data from instrumental and unbiased surrogate variables are available but not the actual predictors of interest. The longitudinal data are fit using linear mixed models that contain random intercepts and account for serial correlation and unequally spaced observations. The motivating application involves a longitudinal study of exposure to two pollutants (predictors) - outdoor fine particulate matter and cigarette smoke - and their association in interactive form with levels of a biomarker of inflammation, leukotriene E4 (LTE 4 , outcome) in asthmatic children. Because the exposure concentrations could not be directly observed, we used measurements from a fixed outdoor monitor and urinary cotinine concentrations as instrumental variables, and we used concentrations of fine ambient particulate matter and cigarette smoke measured with error by personal monitors as unbiased surrogate variables. We applied the derived regression calibration methods to estimate coefficients of the unobserved predictors and their interaction, allowing for direct comparison of toxicity of the different pollutants. We used simulations to verify accuracy of inferential methods based on asymptotic theory.

背景与目标： : 回归校准提供了一种方法，当测量一个或多个预测变量时，可以获得回归模型中固定效应的无偏估计量。测量误差方法的最新发展集中在模型上，该模型包括有误差的测量预测因子之间的交互项，以及分别用于考虑相关数据的模型中的估计方法。在这项工作中，当有工具和无偏替代变量的数据可用但没有实际的预测变量时，我们将得出包含交互项的纵向模型的回归校准估计量和相关的渐近方差的显式和新颖形式。使用线性混合模型拟合纵向数据，该模型包含随机截距，并考虑了序列相关性和不等间距的观测值。激励应用包括纵向研究暴露于两种污染物 (预测因子)-户外细颗粒物和香烟烟雾-以及它们与哮喘儿童炎症生物标志物白三烯E4 (LTE 4，结果) 水平的交互关系。由于无法直接观察到暴露浓度，因此我们使用固定室外监测器的测量值和尿可替宁浓度作为仪器变量，并且我们使用个人监测器错误测量的细环境颗粒物和香烟烟雾的浓度作为无偏替代变量。我们应用派生的回归校准方法来估计未观察到的预测因子及其相互作用的系数，从而可以直接比较不同污染物的毒性。我们使用模拟来验证基于渐近理论的推理方法的准确性。