Promoting Healthy Behaviors Among Adolescents and Young Adults With Intellectual Disability: Protocol for Developing a Digital Intervention With Co-Design Workshops

BACKGROUND

Intellectual disability (ID) is a neurodevelopmental disorder associated with a poorer health profile and higher mortality. Young people with ID have more sedentary lifestyles than their typically developing peers. Consequently, this group is at significant risk of developing lifestyle diseases (ie, noncommunicable diseases) later in life. Increasing physical activity and eating a healthier diet have been argued to be effective ways to improve the health of adolescents and young adults with ID. Digital interventions are a viable option for improving health behaviors.

OBJECTIVE

This research protocol describes a co-design approach using workshops to develop a digital intervention that promotes healthy behaviors, including increasing physical activity and eating a healthier diet, among adolescents and young adults with ID.

METHODS

A participatory design using a co-design approach will be applied as a strategy to include potential users of the digital intervention and other stakeholders in the research process, comprising research design, data collection, and data analysis. A total of 7 to 10 workshops will be conducted aimed at developing a digital intervention and will include procedures for assessing needs; facilitators and barriers to health promotion; physical, mental, and social well-being; participation; and relationships. The workshops will include 12 to 18 stakeholders with experience of clinical practice and research related to young people with ID, including relatives, as well as adolescents and young adults (aged 16-25 years) with mild to moderate ID. Participants will perform a mixture of individual and group work using whiteboards, sticky notes, felt-tip pens, cards, balls, stickers, and wireframe templates. Data analysis will take place concurrently with data collection as an iterative process. Transcribed data from the audio and video recordings of the groups' discussions will be analyzed following a qualitative methodological procedure.

RESULTS

This study protocol provides a systematic record of the scientific methodologies used when developing the digital intervention and provides insights into the potential practical solutions and challenges when following a co-design approach in which relatives and professionals, as well as adolescents and young adults with ID, are included as research partners. Recruitment of participants started in April 2023. Data collection, analysis, and reporting will be completed in December 2023.

CONCLUSIONS

This study will explore the effectiveness of workshops at gathering rich, reliable, and valid data in a co-design approach with participants. The results will provide increased knowledge in how to use technology to develop novel, evidence-based, and scalable interventions that adolescents and young adults with ID can and want to use to motivate physical activity and a healthier diet. The project will provide a simple and cognitively accessible digital solution for promoting lifestyle behaviors tailored to the needs of adolescents and young adults with ID.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/47877.

Effects of an Exercise Program on Cardiometabolic and Mental Health in Children With Overweight or Obesity: A Secondary Analysis of a Randomized Clinical Trial

Importance

Childhood obesity is a risk factor associated with type 2 diabetes, cardiovascular disease, and mental disorders later in life. Investigation of the parallel effects of a defined exercise program on cardiometabolic and mental health in children with overweight or obesity may provide new insights on the potential benefits of exercise on overall health.

Objective

To investigate the effects of a 20-week exercise program on cardiometabolic and mental health in children with overweight or obesity.

Design, Setting, and Participants

This secondary analysis of a parallel-group randomized clinical trial was conducted in Granada, Spain, from November 1, 2014, to June 30, 2016. Data analyses were performed between February 1, 2020, and July 14, 2022. Children with overweight or obesity aged 8 to 11 years were eligible, and the study was performed in an out-of-school context.

Intervention

The exercise program included 3 to 5 sessions/wk (90 min/session) of aerobic plus resistance training for 20 weeks. The wait-list control group continued with their usual routines.

Main Outcomes and Measures

Cardiometabolic outcomes as specified in the trial protocol included body composition (fat mass, fat-free mass, and visceral adipose tissue), physical fitness (cardiorespiratory, speed-agility, and muscular), and traditional risk factors (waist circumference, blood lipid levels, glucose levels, insulin levels, and blood pressure). Cardiometabolic risk score (z score) was calculated based on age and sex reference values for levels of triglycerides, inverted high-density lipoprotein cholesterol, and glucose, the mean of systolic and diastolic blood pressure, and waist circumference. An additional cardiometabolic risk score also included cardiorespiratory fitness. Mental health outcomes included an array of psychological well-being and ill-being indicators.

Results

The 92 participants included in the per-protocol analyses (36 girls [39%] and 56 boys [61%]) had a mean (SD) age of 10.0 (1.1) years. The exercise program reduced the cardiometabolic risk score by approximately 0.38 (95% CI, -0.74 to -0.02) SDs; decreased low-density lipoprotein cholesterol level by -7.00 (95% CI, -14.27 to 0.37) mg/dL (to convert to mmol/L, multiply by 0.0259), body mass index (calculated as weight in kilograms divided by height in meters squared) by -0.59 (95% CI, -1.06 to -0.12), fat mass index by -0.67 (95% CI, -1.01 to -0.33), and visceral adipose tissue by -31.44 (95% CI, -58.99 to -3.90) g; and improved cardiorespiratory fitness by 2.75 (95% CI, 0.22-5.28) laps in the exercise group compared with the control group. No effects were observed on mental health outcomes.

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial, an aerobic plus resistance exercise program improved cardiometabolic health in children with overweight or obesity but had no effect on mental health.

Trial Registration

ClinicalTrials.gov Identifier: NCT02295072.

Effectiveness of a Smartphone App (MINISTOP 2.0) integrated in primary child health care to promote healthy diet and physical activity behaviors and prevent obesity in preschool-aged children: randomized controlled trial

BACKGROUND

Childhood overweight and obesity is a public health priority. We have previously reported the efficacy of a parent-oriented mobile health (mHealth) app-based intervention (MINISTOP 1.0) which showed improvements in healthy lifestyle behaviors. However, the effectiveness of the MINISTOP app in real-world conditions needs to be established.

OBJECTIVE

To evaluate the real-world effectiveness of a 6-month mHealth intervention (MINISTOP 2.0 app) on children's intake of fruits, vegetables, sweet and savory treats, sweet drinks, moderate-to-vigorous physical activity, and screen time (primary outcomes), and on parental self-efficacy (PSE) for promoting healthy lifestyle behaviors, and children's body mass index (BMI) (secondary outcomes).

METHODS

A hybrid type 1 effectiveness-implementation design was utilized. For the effectiveness outcomes, a two-arm, individually randomized controlled trial was conducted. Parents (n = 552) of 2.5-to-3-year-old children were recruited from 19 child health care centers across Sweden, and, randomized to either a control (standard care) or intervention group (MINISTOP 2.0 app). The 2.0 version was adapted and translated into English, Somali and Arabic to increase reach. All recruitment and data collection were conducted by the nurses. Outcomes were assessed at baseline and after six months, using standardized measures (BMI) and a questionnaire (health behaviors, PSE).

RESULTS

Among the participating parents (n = 552, age: 34.1 ± 5.0 years), 79% were mothers and 62% had a university degree. Twenty-four percent (n = 132) of children had two foreign-born parents. At follow-up, parents in the intervention group reported lower intakes of sweet and savory treats (-6.97 g/day; p = 0.001), sweet drinks (-31.52 g/day; p < 0.001), and screen time (-7.00 min/day; p = 0.012) in their children compared to the control group. The intervention group reported higher total PSE (0.91; p = 0.006), PSE for promoting healthy diet (0.34; p = 0.008) and PSE for promoting physical activity behaviors (0.31; p = 0.009) compared to controls. No statistically significant effect was observed for children's BMI z-score. Overall, parents reported high satisfaction with the app, and 54% reported using the app at least once a week.

CONCLUSION

Children in the intervention group had lower intakes of sweet and savory treats, sweet drinks, less screen time (primary outcomes) and their parents reported higher PSE for promoting healthy lifestyle behaviors. Our results from this real-world effectiveness trial support the implementation of the MINISTOP 2.0 app within Swedish child health care.

TRIAL REGISTRATION

Clinicaltrials.gov NCT04147039; https://clinicaltrials.gov/ct2/show/NCT04147039.

Digital multiple health behaviour change intervention targeting online help seekers: protocol for the COACH randomised factorial trial

INTRODUCTION

Unhealthy lifestyle behaviours continue to be highly prevalent, including alcohol consumption, unhealthy diets, insufficient physical activity and smoking. There is a lack of effective interventions which have a large enough reach into the community to improve public health. Additionally, the common co-occurrence of multiple unhealthy behaviours demands investigation of efforts which address more than single behaviours.

METHODS AND ANALYSIS

The effects of six components of a novel digital multiple health behaviour change intervention on alcohol consumption, diet, physical activity and smoking (coprimary outcomes) will be estimated in a factorial randomised trial. The components are designed to facilitate behaviour change, for example, through goal setting or increasing motivation, and are either present or absent depending on allocation (ie, six factors with two levels each). The study population will be those seeking help online, recruited through search engines, social media and lifestyle-related websites. Included will be those who are at least 18 years of age and have at least one unhealthy behaviour. An adaptive design will be used to periodically make decisions to continue or stop recruitment, with simulations suggesting a final sample size between 1500 and 2500 participants. Multilevel regression models will be used to analyse behavioural outcomes collected at 2 months and 4 months postrandomisation.

ETHICS AND DISSEMINATION

Approved by the Swedish Ethical Review Authority on 2021-08-11 (Dnr 2021-02855). Since participation is likely motivated by gaining access to novel support, the main concern is demotivation and opportunity cost if the intervention is found to only exert small effects. Recruitment began on 19 October 2021, with an anticipated recruitment period of 12 months.

TRIAL REGISTRATION NUMBER

ISRCTN16420548.

Mobile phone-based lifestyle support for families with young children in primary health care (MINISTOP 2.0): Exploring behavioral change determinants for implementation using the COM-B model

Background

Obesity in childhood is a public health concern worldwide and mobile phone-based interventions (mHealth) has shown to facilitate obesity prevention. However, more research is needed on the implementation of digital tools in routine primary care. This study explored behavior change determinants for implementing a health promotion mHealth intervention (MINISTOP 2.0 app) targeting parents of 4-year-olds.

Methods

Secondary data from telephone interviews (n = 15) with child health care nurses working within primary child healthcare in Sweden was analyzed using directed content analysis and the COM-B model.

Results

Barriers for implementation included: limited knowledge about using technology and reservations about how and to what extent parents would use mHealth. Potential facilitators included nurses' openness to learn and try new tools, confidence in their role and engagement in reaching parents as well as beliefs that the app could improve practice by prompting dialogue and being a shared platform. Nurses expressed a strong professional identity and shared understanding of their practice, mechanisms that could potentially inhibit or facilitate implementation.

Conclusions

Findings suggest cautious optimism regarding implementing mobile phone-based tools in child primary healthcare in terms of capability, opportunity and motivation among stakeholders. Implementation strategies such as educational outreach visits and making the intervention testable among stakeholders could further facilitate implementation in this clinical context. However, more research is needed on behavior change determinants in different stages of real-world implementation.

Multiple lifestyle behaviour mHealth intervention targeting Swedish college and university students: protocol for the Buddy randomised factorial trial

Introduction

The time during which many attend college or university is an important period for developing health behaviours, with potentially major implications for future health. Therefore, it is concerning that many Swedish students excessively consume alcohol, have unhealthy diets, are not physical active and smoke. The potential of digital interventions which integrate support for change of all of these behaviours is largely unexplored, as are the dismantled effects of the individual components that make up digital lifestyle behaviour interventions.

Methods and analysis

A factorial randomised trial (six factors with two levels each) will be employed to estimate the effects of the components of a novel mHealth multiple lifestyle intervention on alcohol consumption, diet, physical activity and smoking among Swedish college and university students. A Bayesian group sequential design will be employed to periodically make decisions to continue or stop recruitment, with simulations suggesting that between 1500 and 2500 participants will be required. Multilevel regression models will be used to analyse behavioural outcomes collected at 2 and 4 months postrandomisation.

Ethics and dissemination

The study was approved by the Swedish Ethical Review Authority on 2020-12-15 (Dnr 2020-05496). The main concern is the opportunity cost if the intervention is found to only have small effects. However, considering the lack of a generally available evidence-based multiple lifestyle behaviour support to university and college students, this risk was deemed acceptable given the potential benefits from the study.

Recruitment will begin in March 2021, and it is expected that recruitment will last no more than 24 months. A final data set will, therefore, be available in July 2023, and findings will be reported no later than December 2023.

Trial registration number

ISRCTN23310640; Pre-results.

mHealth intervention for multiple lifestyle behaviour change among high school students in Sweden (LIFE4YOUth): protocol for a randomised controlled trial

Background

National surveys in Sweden demonstrate that the majority of young people do not engage in health promoting behaviours at levels recommended by the Public Health Agency of Sweden. The objective of this study is to estimate the effectiveness of a novel mHealth intervention named LIFE4YOUth, which targets multiple lifestyle behaviours (alcohol, diet, physical activity, and smoking) among high school students in Sweden.

Methods

A 2-arm parallel groups single blind randomised controlled trial (1:1) will be employed to estimate the effectiveness of the novel mHealth intervention. Students will be recruited at high schools throughout Sweden, and will be included if they fulfil one of six criteria relating to unhealthy behaviours with respect to alcohol, diet, physical activity and smoking. Eligible participants will be randomised to either receive the novel intervention immediately, or to be placed on a waiting list for 4 months. The intervention consists of a combination of recurring screening, text messages, and an interactive platform which is adaptable to individual preferences. Outcome measures with respect to alcohol, diet, physical activity and smoking will be assessed through questionnaires at 2 and 4 months post randomisation.

Discussion

The findings of this trial could be generalised to a diverse high-school student population as our recruitment encompass a large proportion of schools throughout Sweden with various educational profiles. Furthermore, if effective, the mHealth intervention has good potential to be able to be scaled up and disseminated at high schools nationally.

Trial registration

Registered prospectively on 2020-05-20 in ISRCTN (ISRCTN34468623).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11446-9.

Adapting a Parental Support App to Promote Healthy Diet and Physical Activity Behaviors (MINISTOP) for a Multi-Ethnic Setting: A Qualitative Study on the Needs and Preferences of Parents and Nurses within Swedish Child Health Care

Early efforts for prevention of childhood overweight and obesity are needed. In order to adapt an app promoting healthy diet and physical activity behaviors in children (MINISTOP 1.0) for multi-ethnic communities, we explored: (1) needs and concerns among Somali-, Arabic-, and Swedish-speaking parents in terms of supporting healthy diet and activity behaviors in their children; (2) nurses’ perceptions of parental needs and concerns in relation to diet and physical activity behaviors; and (3) how the features and content of the MINISTOP 1.0 app could be refined to better support health behaviors in children, among both parents and nurses. Focus groups with Somali-, Arabic-, and Swedish-speaking parents (n = 15), and individual interviews with nurses (n = 15) were conducted. Parents expressed several challenges in supporting children’s health behaviors, the need for a tailored app, and alternative ways of accessing the content (audio/video). Nurses emphasized the need of supporting parents early, and the value of a shared platform in different languages, to facilitate communication. This study contributes valuable insights about parental needs and relevant adaptations to a parental support app, such as addition of audio/video files for increased accessibility. This adapted app version—MINISTOP 2.0, can be useful for childhood obesity prevention in multi-ethnic communities.

Cardiorespiratory fitness, muscular strength, and obesity in adolescence and later chronic disability due to cardiovascular disease: a cohort study of 1 million men

Aims

Cardiorespiratory fitness, muscular strength, and obesity in adulthood are risk factors for cardiovascular disease (CVD). However, little is known regarding the associations of these risk factors, already in adolescence, with later disability due to chronic CVD. Hence, we investigated associations of cardiorespiratory fitness, muscular strength, and body mass index (BMI) in adolescence with later chronic disability due to specific causes of CVD disability (i.e. cerebrovascular disease, ischaemic heart disease and heart failure).

Methods and results

This population-based cohort study included 1 078 685 male adolescents (16–19 years) from the Swedish military conscription register from 1972 to 1994. Cardiorespiratory fitness (bicycle ergometer test), muscular strength (knee extension strength), and BMI were measured during the conscription examination. Information about disability pension due to CVD was retrieved from the Social Insurance Agency during a mean follow-up of 28.4 years. Cardiorespiratory fitness was strongly and inversely associated with later risk of chronic CVD disability for all investigated causes. The association was particularly strong for ischaemic heart diseases (hazard ratio 0.11, 95% confidence interval 0.05–0.29 for highest vs. lowest fitness-quintiles). Furthermore, overweight/obesity were associated with CVD disability for all investigated causes. Conversely, associations of muscular strength with CVD disability were generally weak.

Conclusions

This study provides evidence for associations between low levels of cardiorespiratory fitness and obesity with later risk of chronic disability due to CVD. Preventive actions may begin at young ages and include promotion of cardiorespiratory fitness and healthy body weight.

MINISTOP 2.0: a smartphone app integrated in primary child health care to promote healthy diet and physical activity behaviours and prevent obesity in preschool-aged children: protocol for a hybrid design effectiveness-implementation study

Background

Childhood obesity is still a major health problem in many countries, including Sweden. Childhood obesity and obesity-related behaviours in childhood, such as low physical activity and unhealthy eating habits, tend to track into adulthood, which highlights the need for early prevention. Our aims are to evaluate whether a parent-oriented mobile health app (the MINISTOP 2.0 app) integrated into primary child health care can improve diet and physical activity behaviours and reduce the prevalence of overweight and obesity in preschool-aged children as well as to evaluate the implementation among child health care nurses and parents.

Methods

This trial uses a hybrid type 1 effectiveness-implementation design. Families (n = 500) who attend a routine visit to one of 15–20 primary child health care centres throughout Sweden, when their child is 2.5 years, are offered participation in a randomised controlled trial (effectiveness evaluation). After acceptance, families will be randomised (1:1) to control or intervention groups. The intervention group receives a 6-month parent-oriented smartphone intervention aimed at improving the dietary and activity behaviours of their child (the MINISTOP 2.0 app) and the control group receives routine child health care. Dietary habits, physical activity and screen time (primary outcomes), body weight and height in children, and parental self-efficacy (secondary outcomes) are measured at baseline and at 6 months post randomisation. Implementation outcomes (i.e. perceived acceptability, appropriateness, and feasibility) of the intervention will be assessed among primary child health care nurses and parents in the trial through questionnaires and qualitative interviews.

Discussion

This trial will evaluate whether the MINISTOP 2.0 app can be used in primary child health care to improve diet and physical activity behaviours, and prevent overweight and obesity, in preschool-aged children. If effectiveness is proven, and the MINISTOP 2.0 app is considered acceptable, appropriate and feasible, it can be implemented nationally as part of the preventive strategies to combat childhood obesity provided by routine child health care.

Trial registration

The trial was registered at the Clinicaltrials.gov register platform (ID NCT04147039) on 31 October 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-09808-w.

Hip and wrist accelerometers showed consistent associations with fitness and fatness in children aged 8-12 years

AIM

Physical activity (PA) has traditionally been measured wearing accelerometers on the hip, but they are increasingly being worn on the wrist. We compared hip and wrist accelerometers with regard to their acceptability and any associations between PA and fatness and fitness.

METHODS

This cross-sectional study comprised 103 children aged 8-12 years (62% boys) who participated in the ActiveBrains trial by the University of Granada, Spain, in 2014-2016. The children wore both ActiGraph GT3X+ hip and wrist accelerometers round the clock for 7 days. The acceptability of both placements was evaluated by a questionnaire, while the children's fat mass index, waist circumference and cardiorespiratory fitness (CRF) were assessed.

RESULTS

Wearing wrist accelerometers caused less disturbance, mainly because hip accelerometers caused more issues during the night. The measurements from both placements showed that lower PA levels were associated with fatness and that higher PA levels were associated with better CRF.

CONCLUSION

Both placements showed consistent results with regard to measuring associations between PA levels and fatness and fitness. However, wearing them on the wrist caused less discomfort at night. Future studies are needed to confirm the best placement for accelerometers during PA studies.

The Mobile Health Multiple Lifestyle Behavior Interventions Across the Lifespan (MoBILE) Research Program: Protocol for Development, Evaluation, and Implementation

BACKGROUND

Clustering of multiple lifestyle risk behaviors has been associated with a greater risk of noncommunicable diseases and mortality than one lifestyle risk behavior or no lifestyle risk behaviors. The National Board of Health and Welfare in Sweden reported in 2018 that it is important to provide additional support to individuals with multiple lifestyle risk behaviors, as risks from these behaviors are multiplicative rather than additive. However, the same report emphasized that there is a lack of knowledge regarding interventions that support changes to unhealthy lifestyle behaviors.

OBJECTIVE

The MoBILE (Mobile health Multiple lifestyle Behavior Interventions across the LifEspan) research program has brought together two Swedish research groups supported by international collaborators. Through this collaboration, we aim to design and evaluate a number of novel and tailored mobile health (mHealth) multiple lifestyle behavior interventions across the life span of different health care populations. In addition, the MoBILE research program will extend ongoing research to include mHealth interventions for migrant pregnant women and children.

METHODS

Each project within the MoBILE program will focus on a specific group: pregnant women, preschool children, high school and university students, and adults in primary and clinical care. All the projects will follow the same 4 phases: requirements, development, evaluation, and implementation. During the requirements phase, implementers and end users will aid the design of content and functionality of the interventions. In the development phase, findings from the first phase will be synthesized with expert domain knowledge and theoretical constructs to create interventions tailored to the target groups. The third phase, evaluation, will comprise randomized controlled trials conducted to estimate the effects of the interventions on multiple lifestyle risk behaviors (eg, alcohol, nutrition, physical activity, and smoking). The final phase will investigate how the interventions, if found effective, can be disseminated into different health care contexts.

RESULTS

The research program commenced in 2019, and the first results will be available in 2020. Projects involving pregnant women, preschool children, and high school and university students will be completed in the first 3 years, with the remaining projects being planned for the program's final 3 years.

CONCLUSIONS

The development of evidence-based digital tools is complex, as they should be guided by theoretical frameworks, and requires large interdisciplinary teams with competence in technology, behavioral science, and lifestyle-specific areas. Individual researchers or smaller research groups developing their own tools is not the way forward, as it means reinventing the wheel over and over again. The MoBILE research program therefore aims to join forces and learn from the past 10 years of mHealth research to maximize scientific outcomes, as well as the use of financial resources to expand the growing body of evidence for mHealth lifestyle behavior interventions.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/14894.

Fat and fat-free mass of healthy Swedish children show tracking during early life, but there are differences

AIM

Obesity may start early in life. We investigated relationships between size and body composition variables in infancy and at 4 years of age using valid estimates of body composition. The results were compared to those obtained when body mass index (BMI) was used to estimate body fatness at 4 years.

METHODS

Using air displacement plethysmography, size, fat mass and fat-free mass were studied, between 2007 and 2015, in 253 full-term healthy Swedish children at 1 week, 12 weeks and 4 years of age.

RESULTS

Positive associations between variables in infancy and at 4 years were found at 1 and 12 weeks for weight, height, BMI, fat-free mass and fat-free mass index (p ≤ 0.002) and for fat mass, per cent body fat and fat mass index (p ≤ 0.04) at 12 weeks. Fat mass gained during infancy correlated positively (p ≤ 0.031) with per cent fat mass, fat mass index and BMI, all at 4 years. In girls, gains in fat-free mass during infancy correlated with BMI (p = 0.0005) at 4 years.

CONCLUSION

The results provide information regarding body composition trajectories during early life and demonstrate limitations of BMI as a proxy for body fatness when relating early weight gain to variables, relevant for later obesity risk.

A Smartphone App to Promote Healthy Weight Gain, Diet, and Physical Activity During Pregnancy (HealthyMoms): Protocol for a Randomized Controlled Trial

Background

Excessive gestational weight gain is common and associated with adverse outcomes both in the short and long term. Although traditional lifestyle-based interventions have shown to mitigate excess gestational weight gain, little is known about whether mobile Health (mHealth) apps can promote healthy weight gain, diet, and physical activity during pregnancy.

Objective

The primary aim of the HealthyMoms trial is to determine the effectiveness of a smartphone app (HealthyMoms) for mitigating excess gestational weight gain during pregnancy. Secondary aims are to determine the effectiveness of the app on dietary habits, physical activity, body fatness, and glycemia during pregnancy.

Methods

HealthyMoms is a two-arm randomized controlled trial. Women are being recruited at routine visits at the maternity clinics in Linköping, Norrköping and Motala, Sweden. Women are randomized to the control or intervention group (n=150 per group). All women will receive standard care, and women in the intervention group will also receive the HealthyMoms smartphone app.

Results

Recruitment of participants to the trial was initiated in October 2017, and 190 women have so far completed the baseline measurement. The baseline measures are estimated to be finalized in December 2019, and the follow-up measures are estimated to be completed in June 2020.

Conclusions

This project will evaluate a novel smartphone app intervention integrated with existing maternity health care. If successful, it has great potential to be implemented nationally in order to promote healthy weight gain and health behaviors during pregnancy.

International Registered Report Identifier (IRRID)

DERR1-10.2196/13011

Fitness and Body Mass Index During Adolescence and Disability Later in Life: A Cohort Study

BACKGROUND

Low physical fitness, obesity, and the combination of the two in adolescence may be related to risk for disability in adulthood, but this has rarely been studied.

OBJECTIVE

To examine individual and combined associations of cardiorespiratory fitness and obesity in male adolescents with later receipt of a disability pension due to all and specific causes.

DESIGN

Population-based cohort study.

SETTING

Sweden.

PARTICIPANTS

1 079 128 Swedish adolescents aged 16 to 19 years who were conscripted into the military between 1972 and 1994.

MEASUREMENTS

Cardiorespiratory fitness and body mass index (BMI) were measured at conscription and were related to information on later receipt of a disability pension obtained from the Social Insurance Agency.

RESULTS

Over a median follow-up of 28.3 years, 54 304 men were granted a disability pension. Low cardiorespiratory fitness was strongly associated with later receipt of a disability pension due to all causes (hazard ratio, 3.74 [95% CI, 3.55 to 3.95] for lowest vs. highest fitness decile) and specific causes (psychiatric, musculoskeletal, injuries, nervous system, circulatory, and tumors). Obesity was associated with greater risk for receipt of a disability pension due to all and specific causes, with the greatest risks observed for class II and III obesity. Compared with being unfit, being moderately or highly fit was associated with attenuated risk for receipt of a disability pension across BMI categories.

LIMITATION

The cohort did not include women, had data on smoking and alcohol intake only in a subsample, and lacked repeated measures of exposures and covariates.

CONCLUSION

Low cardiorespiratory fitness, obesity, and the combination of the two were strongly associated with later chronic disability due to a wide range of diseases and causes. Although additional well-designed studies are required, these findings support the importance of high cardiorespiratory fitness and healthy body weight during adolescence to prevent later chronic disease.

PRIMARY FUNDING SOURCE

Karolinska Institutet.

Physical fitness in relation to later body composition in pre-school children

OBJECTIVES

Although physical fitness is considered a marker of health in youth, little is known whether physical fitness in pre-school age is related to later body composition. Thus, this study investigated (i) associations of physical fitness at 4.5years of age with body composition 12months later and (ii) whether improvements in physical fitness during the 12-month follow-up were associated with changes in body composition.

DESIGN

This study included 142 children, measured at 4.5 and 5.5years, from the control group of the MINISTOP trial.

METHODS

Physical fitness (cardiorespiratory fitness, lower- and upper-body muscular strength and motor fitness) was measured using the PREFIT test battery. Body composition was assessed using air-displacement plethysmography.

RESULTS

In adjusted regression analyses, greater cardiorespiratory fitness, lower-body muscular strength and motor fitness at 4.5years were associated with a lower fat mass index at 5.5years (standardized β=-0.182 to -0.229, p≤0.028). Conversely, greater cardiorespiratory fitness, lower- and upper-body muscular strength as well as motor fitness at 4.5years of age were associated with a higher fat-free mass index (standardized β=0.255-0.447, p≤0.001). Furthermore, improvements in cardiorespiratory fitness, lower-body muscular strength and motor fitness during the 12-month follow-up period were associated with decreases in fat mass index and/or % fat mass.

CONCLUSIONS

In conclusion, the results of this study provide evidence of the importance of physical fitness early in life. Nevertheless, further studies are needed in order to clarify the influence of physical fitness in the pre-school age with later health outcomes.

Muscular weakness in adolescence is associated with disability 30 years later: a population-based cohort study of 1.2 million men

Objective

To investigate the associations of muscular strength in adolescence with later disability pension (DP), across different body mass index (BMI) categories and in combination with aerobic fitness.

Method

This prospective cohort study consisted of males aged 16–19 years, recruited from the Swedish military conscription register between 1969 and 1994. A total of 1 212 503 adolescents met all the inclusion criteria and were therefore included in the analyses. Knee extension, handgrip and elbow flexion strength and aerobic fitness (bicycle ergometer test) were measured during conscription. Causes of DP were retrieved from the Social Insurance Office between years 1971 and 2012 (average follow-up time: 29.6 years).

Results

Knee extension strength in adolescence was inversely associated with men’s risk of obtaining DP due to all causes (HR 1.40, 95% CI 1.36 to 1.44 for lowest vs highest strength quintile). Thus, muscular weakness was associated with DP. The risk associated with low muscular strength differed between specific causes of DP and the strongest associations were found for psychiatric, nervous system and other causes (HRs between 1.47 and 1.90 for lowest vs highest quintile). Being strong was associated with lower DP risk across BMI categories and being unfit, weak and obese was associated with the highest DP risk (HR 3.70, 95% CI 2.99 to 4.58).

Conclusion

There was a strong association between muscular weakness and disability. A combination of muscular weakness and low aerobic fitness was an especially important risk factor for disability. This adds weight to call for muscular strength and fitness enhancing exercise for adolescents in all BMI categories.

Longitudinal Physical Activity, Body Composition, and Physical Fitness in Preschoolers

PURPOSE

This study aimed to investigate longitudinal associations of objectively measured physical activity (PA) and sedentary behavior (SB) with body composition and physical fitness at a 12-month follow-up in healthy Swedish 4-yr-old children.

METHODS

The data from the population-based MINISTOP trial were collected between 2014 and 2016, and this study included the 138 children who were in the control group. PA and SB were assessed using the wrist-worn ActiGraph (wGT3x-BT) accelerometer during seven 24-h periods and, subsequently, defined as SB, light-intensity PA, moderate-intensity PA, vigorous-intensity PA (VPA), and moderate-to-vigorous PA (MVPA). Body composition was measured using air-displacement plethysmography and physical fitness (cardiorespiratory fitness, lower and upper muscular strength as well as motor fitness) by the PREFIT fitness battery. Linear regression and isotemporal substitution models were applied.

RESULTS

Greater VPA and MVPA at the age of 4.5 yr were associated with higher fat-free mass index (FFMI) at 5.5 yr (P < 0.001 and P = 0.044, respectively). Furthermore, greater VPA and MVPA at the age of 4.5 yr were associated with higher scores for cardiorespiratory fitness, lower body muscular strength, and motor fitness at 12-month follow-up (P = 0.001 to P = 0.031). Substituting 5 min·d of SB, light-intensity PA, or moderate-intensity PA for VPA at the age of 4.5 yr were associated with higher FFMI, and with greater upper and lower muscular strength at 12-month follow-up (P < 0.001 to P = 0.046).

CONCLUSION

Higher VPA and MVPA at the age of 4.5 yr were significantly associated with higher FFMI and better physical fitness at 12-month follow-up. Our results indicate that promoting high-intensity PA at young ages may have long-term beneficial effects on childhood body composition and physical fitness, in particular muscular strength.

Correlates of ideal cardiovascular health in European adolescents: The HELENA study

BACKGROUND AND AIMS

The ideal cardiovascular health (iCVH) construct consists of 4 health behaviors (smoking status, body mass index, physical activity and diet) and 3 health factors (total cholesterol, blood pressure and fasting glucose). A greater number of iCVH components in adolescence are related to better cardiovascular health, but little is known about the correlates of iCVH in adolescents. Thus, the aim of the study was to examine correlates of iCVH in European adolescents.

METHODS AND RESULTS

The study comprised 637 European adolescents with complete iCVH data. Participants were part of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study, a cross-sectional, multicenter study conducted in 9 different European countries. Correlates investigated were sex and age, family affluence scale, maternal education, geographic location, sleep time, television viewing, duration of pregnancy, birth weight and breastfeeding. Younger adolescents, those whose mothers had medium/high education or those who watched television less than 2 h per day had a greater number of iCVH components compared to those who were older, had a mother with low education or watched television 2 h or more daily (P ≤ 0.01).

CONCLUSION

Since in our study older adolescents had worse iCVH than younger adolescents, early promotion of cardiovascular health may be important. Future studies may also investigate the usefulness of limiting television viewing to promote iCVH. Finally, since adolescents of mothers with low education had poorer iCVH, it may be of special interest to tailor public health promotion to adolescents from families with low socioeconomic status.

Longitudinal assessment of body composition in healthy Swedish children from 1 week until 4 years of age

BACKGROUND/OBJECTIVES

Knowledge of longitudinal body composition development is required to identify the mechanisms behind childhood overweight and obesity and to prevent these conditions. However, accurate data on this development in early childhood are lacking. Our aim was to describe the longitudinal body composition development in healthy young Swedish children.

SUBJECTS/METHODS

Body size and composition were assessed in 26 children using air-displacement plethysmography (1 and 12 weeks and 4.4 years of age) and isotope dilution (1.5 and 3 years of age) and compared with available reference data.

RESULTS

Body fat (%) for boys (n=16) was 12.8±3.9 (1 week), 25.6±4.8 (12 weeks), 28.2±3.8 (1.5 years), 27.3±5.1 (3 years) and 26.1±3.5 (4.4 years). For girls (n=10) these values were 15.3±2.9, 25.7±3.9, 27.9±3.3, 26.3±7.2 and 26.0±5.3, respectively. These values were above the Fomon reference values at 1.5 years of age and later and higher than the Butte reference (P<0.05) for boys at 1.5 years of age. At all ages the coefficients of variation were higher for body fat (%) (12-30%) than for BMI (4-11%).

CONCLUSIONS

At 4 years of age our children had more body fat than indicated by reference data. This high level may have already been established at 1.5 years of age but our small sample and the lack of appropriate reference data limit the possibility of drawing firm conclusions. Our results demonstrate the limitations of BMI when investigating overweight and obesity in early life and highlight the need for appropriate reference body composition data in infants and young children.European Journal of Clinical Nutrition advance online publication, 23 August 2017; doi:10.1038/ejcn.2017.125.

Prevalence of ideal cardiovascular health in European adolescents: The HELENA study

BACKGROUND

The ideal cardiovascular health (iCVH) construct consists of 4 health behaviours and 3 health factors and is strongly related to later cardiovascular disease. However, the prevalence of iCVH in European adolescents is currently unknown.

METHODS

The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study is a cross-sectional, multicentre study conducted in 9 European countries during 2006-2007 and included 3528 adolescents (1683 boys and 1845 girls) between 12.5 and 17.5years of age. Status (ideal vs. non-ideal) for the health behaviours (smoking status, body mass index, physical activity and diet) and health factors (total cholesterol, blood pressure and fasting glucose) were determined.

RESULTS

Overall, the prevalence of ideal health behaviours was low; non-smoking (60.9% ideal), body mass index (76.8%), physical activity (62.1%), and diet (1.7%). The prevalence of ideal health factors was; total cholesterol (65.8%), blood pressure (62.0%) and plasma glucose (88.8%).

CONCLUSIONS

The low prevalence of iCVH behaviours, especially diet and physical activity, identified in European adolescents is likely to influence later cardiovascular health which strongly motivates efforts to increase ideal health behaviours in this population.

Mobile-based intervention intended to stop obesity in preschool-aged children: the MINISTOP randomized controlled trial

Background: Traditional obesity prevention programs are time- and cost-intensive. Mobile phone technology has been successful in changing behaviors and managing weight; however, to our knowledge, its potential in young children has yet to be examined.Objective: We assessed the effectiveness of a mobile health (mHealth) obesity prevention program on body fat, dietary habits, and physical activity in healthy Swedish children aged 4.5 y.Design: From 2014 to 2015, 315 children were randomly assigned to an intervention or control group. Parents in the intervention group received a 6-mo mHealth program. The primary outcome was fat mass index (FMI), whereas the secondary outcomes were intakes of fruits, vegetables, candy, and sweetened beverages and time spent sedentary and in moderate-to-vigorous physical activity. Composite scores for the primary and secondary outcomes were computed.Results: No statistically significant intervention effect was observed for FMI between the intervention and control group (mean ± SD: -0.23 ± 0.56 compared with -0.20 ± 0.49 kg/m²). However, the intervention group increased their mean composite score from baseline to follow-up, whereas the control group did not (+0.36 ± 1.47 compared with -0.06 ± 1.33 units; P = 0.021). This improvement was more pronounced among the children with an FMI above the median (4.11 kg/m²) (P = 0.019). The odds of increasing the composite score for the 6 dietary and physical activity behaviors were 99% higher for the intervention group than the control group (P = 0.008).Conclusions: This mHealth obesity prevention study in preschool-aged children found no difference between the intervention and control group for FMI. However, the intervention group showed a considerably higher postintervention composite score (a secondary outcome) than the control group, especially in children with a higher FMI. Further studies targeting specific obesity classes within preschool-aged children are warranted. This trial was registered at clinicaltrials.gov as NCT02021786.

A Mobile Phone Based Method to Assess Energy and Food Intake in Young Children: A Validation Study against the Doubly Labelled Water Method and 24 h Dietary Recalls

Mobile phones are becoming important instruments for assessing diet and energy intake. We developed the Tool for Energy Balance in Children (TECH), which uses a mobile phone to assess energy and food intake in pre-school children. The aims of this study were: (a) to compare energy intake (EI) using TECH with total energy expenditure (TEE) measured via doubly labelled water (DLW); and (b) to compare intakes of fruits, vegetables, fruit juice, sweetened beverages, candy, ice cream, and bakery products using TECH with intakes acquired by 24 h dietary recalls. Participants were 39 healthy, Swedish children (5.5 ± 0.5 years) within the ongoing Mobile-based Intervention Intended to Stop Obesity in Preschoolers (MINISTOP) obesity prevention trial. Energy and food intakes were assessed during four days using TECH and 24 h telephone dietary recalls. Mean EI (TECH) was not statistically different from TEE (DLW) (5820 ± 820 kJ/24 h and 6040 ± 680 kJ/24 h, respectively). No significant differences in the average food intakes using TECH and 24 h dietary recalls were found. All food intakes were correlated between TECH and the 24 h dietary recalls (ρ = 0.665-0.896, p < 0.001). In conclusion, TECH accurately estimated the average intakes of energy and selected foods and thus has the potential to be a useful tool for dietary studies in pre-school children, for example obesity prevention trials.

A new mobile phone-based tool for assessing energy and certain food intakes in young children: a validation study

Background

Childhood obesity is an increasing health problem globally. Obesity may be established already at pre-school age. Further research in this area requires accurate and easy-to-use methods for assessing the intake of energy and foods. Traditional methods have limited accuracy, and place large demands on the study participants and researchers. Mobile phones offer possibilities for methodological advancements in this area since they are readily available, enable instant digitalization of collected data, and also contain a camera to photograph pre- and post-meal food items. We have recently developed a new tool for assessing energy and food intake in children using mobile phones called the Tool for Energy Balance in Children (TECH).

Objective

The main aims of our study are to (1) compare energy intake by means of TECH with total energy expenditure (TEE) measured using a criterion method, the doubly labeled water (DLW) method, and (2) to compare intakes of fruits and berries, vegetables, juice, and sweetened beverages assessed by means of TECH with intakes obtained using a Web-based food frequency questionnaire (KidMeal-Q) in 3 year olds.

Methods

In this study, 30 Swedish 3 year olds were included. Energy intake using TECH was compared to TEE measured using the DLW method. Intakes of vegetables, fruits and berries, juice, as well as sweetened beverages were assessed using TECH and compared to the corresponding intakes assessed using KidMeal-Q. Wilcoxon matched pairs test, Spearman rank order correlations, and the Bland-Altman procedure were applied.

Results

The mean energy intake, assessed by TECH, was 5400 kJ/24h (SD 1500). This value was not significantly different (P=.23) from TEE (5070 kJ/24h, SD 600). However, the limits of agreement (2 standard deviations) in the Bland-Altman plot for energy intake estimated using TECH compared to TEE were wide (2990 kJ/24h), and TECH overestimated high and underestimated low energy intakes. The Bland-Altman plots for foods showed similar patterns. The mean intakes of vegetables, fruits and berries, juice, and sweetened beverages estimated using TECH were not significantly different from the corresponding intakes estimated using KidMeal-Q. Moderate but statistically significant correlations (ρ=.42-.46, P=.01-.02) between TECH and KidMeal-Q were observed for intakes of vegetables, fruits and berries, and juice, but not for sweetened beverages.

Conclusion

We found that one day of recordings using TECH was not able to accurately estimate intakes of energy or certain foods in 3 year old children.

A web- and mobile phone-based intervention to prevent obesity in 4-year-olds (MINISTOP): a population-based randomized controlled trial

BACKGROUND

Childhood obesity is an increasing health problem globally. Overweight and obesity may be established as early as 2-5 years of age, highlighting the need for evidence-based effective prevention and treatment programs early in life. In adults, mobile phone based interventions for weight management (mHealth) have demonstrated positive effects on body mass, however, their use in child populations has yet to be examined. The aim of this paper is to report the study design and methodology of the MINSTOP (Mobile-based Intervention Intended to Stop Obesity in Preschoolers) trial.

METHODS/DESIGN

A two-arm, parallel design randomized controlled trial in 300 healthy Swedish 4-year-olds is conducted. After baseline measures, parents are allocated to either an intervention- or control group. The 6- month mHealth intervention consists of a web-based application (the MINSTOP app) to help parents promote healthy eating and physical activity in children. MINISTOP is based on the Social Cognitive Theory and involves the delivery of a comprehensive, personalized program of information and text messages based on existing guidelines for a healthy diet and active lifestyle in pre-school children. Parents also register physical activity and intakes of candy, soft drinks, vegetables as well as fruits of their child and receive feedback through the application. Primary outcomes include body fatness and energy intake, while secondary outcomes are time spent in sedentary, moderate, and vigorous physical activity, physical fitness and intakes of fruits and vegetables, snacks, soft drinks and candy. Food and energy intake (Tool for Energy balance in Children, TECH), body fatness (pediatric option for BodPod), physical activity (Actigraph wGT3x-BT) and physical fitness (the PREFIT battery of five fitness tests) are measured at baseline, after the intervention (six months after baseline) and at follow-up (12 months after baseline).

DISCUSSION

This novel study will evaluate the effectiveness of a mHealth program for mitigating gain in body fatness among 4-year-old children. If the intervention proves effective it has great potential to be implemented in child-health care to counteract childhood overweight and obesity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02021786 ; 20 Dec 2013.

Evaluations of Actiheart, IDEEA® and RT3 monitors for estimating activity energy expenditure in free-living women

Activity energy expenditure (AEE) during free-living conditions can be assessed using devices based on different principles. To make proper comparisons of different devices' capacities to assess AEE, they should be evaluated in the same population. Thus, in the present study we evaluated, in the same group of subjects, the ability of three devices to assess AEE in groups and individuals during free-living conditions. In twenty women, AEE was assessed using RT3 (three-axial accelerometry) (AEERT3), Actiheart (a combination of heart rate and accelerometry) (AEEActi) and IDEEA (a multi-accelerometer system) (AEEIDEEA). Reference AEE (AEEref) was assessed using the doubly labelled water method and indirect calorimetry. Average AEEActi was 5760 kJ per 24 h and not significantly different from AEEref (5020 kJ per 24 h). On average, AEERT3 and AEEIDEEA were 2010 and 1750 kJ per 24 h lower than AEEref, respectively (P < 0·001). The limits of agreement (± 2 sd) were 2940 (Actiheart), 1820 (RT3) and 2650 (IDEEA) kJ per 24 h. The variance for AEERT3 was lower than for AEEActi (P = 0·006). The RT3 classified 60 % of the women in the correct activity category while the corresponding value for IDEEA and Actiheart was 30 %. In conclusion, the Actiheart may be useful for groups and the RT3 for individuals while the IDEEA requires further development. The results are likely to be relevant for a large proportion of Western women of reproductive age and demonstrate that the procedure selected to assess physical activity can greatly influence the possibilities to uncover important aspects regarding interactions between physical activity, diet and health.

Total body fat content versus BMI in 4-year-old healthy Swedish children

Childhood overweight and obesity, a worldwide problem, is generally identified using BMI (body mass index). However, this application of BMI has been little investigated in children below 5 years of age due to a lack of appropriate methods to assess body composition. Therefore, we used air displacement plethysmography (ADP) to study 4.4-year old boys and girls since this method is accurate in young children if they accept the requirements of the measurement. The purpose was to analyze the relationship between BMI and body fat in these children. Body composition was assessed in 76 (43 boys, 33 girls) of the 84 children brought to the measurement session. Boys and girls contained 25.2 ± 4.7 and 26.8 ± 4.0% body fat, respectively. BMI-based cut-offs for overweight could not effectively identify children with a high body fat content. There was a significant (P < 0.001) but weak (r = 0.39) correlation between BMI and body fat (%). In conclusion, requirements associated with a successful assessment of body composition by means of ADP were accepted by most 4-year-olds. Furthermore, BMI-based cut-offs for overweight did not effectively identify children with a high body fatness and BMI explained only a small proportion of the variation in body fat (%) in this age group.

Body-composition development during early childhood and energy expenditure in response to physical activity in 1.5-y-old children

BACKGROUND

The prevalence of childhood overweight and obesity has increased recently, but the mechanisms involved are incompletely known. Previous research has shown a correlation between the percentage of total body fat (TBF) and physical activity level (PAL). However, the PAL values used may involve a risk of spurious correlations because they are often based on predicted rather than measured estimates of resting energy metabolism.

OBJECTIVES

We studied the development of body composition during early childhood and the relation between the percentage of TBF and PAL on the basis of the measured resting energy metabolism.

DESIGN

Body composition was previously measured in 108 children when they were 1 and 12 wk old. When 44 of these children (21 girls and 23 boys) were 1.5 y old, their total energy expenditure and TBF were assessed by using the doubly labeled water method. Resting energy metabolism, which was assessed by using indirect calorimetry, was used to calculate PAL.

RESULTS

Significant correlations were shown for TBF (r = 0.32, P = 0.035) and fat-free mass (r = 0.34, P = 0.025) between values (kg) assessed at 12 wk and 1.5 y of age. For TBF (kg) a significant interaction (P = 0.035) indicated a possible sex difference. PAL at 1.5 y was negatively correlated with the percentage of TBF (r = -0.40, P = 0.0076) and the increase in the percentage of TBF between 12 wk and 1.5 y (r = -0.38, P = 0.0105).

CONCLUSIONS

The results indicate that body fatness and physical activity interact during early childhood and thereby influence obesity risk. Our results are based on a small sample, but nevertheless, they motivate additional studies in boys compared with girls regarding the development of body composition during early life.

Family 7 cellobiohydrolases from Phanerochaete chrysosporium: crystal structure of the catalytic module of Cel7D (CBH58) at 1.32 A resolution and homology models of the isozymes

Cellobiohydrolase 58 (Cel7D) is the major cellulase produced by the white-rot fungus Phanerochaete chrysosporium, constituting approximately 10 % of the total secreted protein in liquid culture on cellulose. The enzyme is classified into family 7 of the glycosyl hydrolases, together with cellobiohydrolase I (Cel7A) and endoglucanase I (Cel7B) from Trichoderma reesei. Like those enzymes, it catalyses cellulose hydrolysis with net retention of the anomeric carbon configuration. The structure of the catalytic module (431 residues) of Cel7D was determined at 3.0 A resolution using the structure of Cel7A from T. reesei as a search model in molecular replacement, and ultimately refined at 1.32 A resolution. The core structure is a beta-sandwich composed of two large and mainly antiparallel beta-sheets packed onto each other. A long cellulose-binding groove is formed by loops on one face of the sandwich. The catalytic residues are conserved and the mechanism is expected to be the same as for other family members. The Phanerochaete Cel7D binding site is more open than that of the T. reesei cellobiohydrolase, as a result of deletions and other changes in the loop regions, which may explain observed differences in catalytic properties. The binding site is not, however, as open as the groove of the corresponding endoglucanase. A tyrosine residue at the entrance of the tunnel may be part of an additional subsite not present in the T. reesei cellobiohydrolase. The Cel7D structure was used to model the products of the five other family 7 genes found in P. chrysosporium. The results suggest that at least two of these will have differences in specificity and possibly catalytic mechanism, thus offering some explanation for the presence of Cel7 isozymes in this species, which are differentially expressed in response to various growth conditions.

Structural basis for enantiomer binding and separation of a common beta-blocker: crystal structure of cellobiohydrolase Cel7A with bound (S)-propranolol at 1.9 A resolution

Cellobiohydrolase Cel7A (previously called CBH 1), the major cellulase produced by the mould fungus Trichoderma reesei, has been successfully exploited as a chiral selector for separation of stereo-isomers of some important pharmaceutical compounds, e.g. adrenergic beta-blockers. Previous investigations, including experiments with catalytically deficient mutants of Cel7A, point unanimously to the active site as being responsible for discrimination of enantiomers. In this work the structural basis for enantioselectivity of basic drugs by Cel7A has been studied by X-ray crystallography. The catalytic domain of Cel7A was co-crystallised with the (S)-enantiomer of a common beta-blocker, propranolol, at pH 7, and the structure of the complex was determined and refined at 1. 9 A resolution. Indeed, (S)-propranolol binds at the active site, in glucosyl-binding subsites -1/+1. The catalytic residues Glu212 and Glu217 make tight salt links with the secondary amino group of (S)-propranolol. The oxygen atom attached to the chiral centre of (S)-propranolol forms hydrogen bonds to the nucleophile Glu212 O(epsilon1) and to Gln175 N(epsilon2), whereas the aromatic naphthyl moiety stacks with the indole ring of Trp376 in site +1. The bidentate charge interaction with the catalytic glutamate residues is apparently crucial, since no enantioselectivity has been obtained with the catalytically deficient mutants E212Q and E217Q. Activity inhibition experiments with wild-type Cel7A were performed in conditions close to those used for crystallisation. Competitive inhibition constants for (R)- and (S)-propranolol were determined at 220 microM and 44 microM, respectively, corresponding to binding free energies of 20 kJ/mol and 24 kJ/mol, respectively. The K(i) value for (R)-propranolol was 57-fold lower than the highest concentration, 12.5 mM, used in co-crystallisation experiments. Still several attempts to obtain a complex with the (R)-enantiomer have failed. By using cellobiose as a selective competing ligand, the retention of the enantiomers of propranolol on the chiral stationary phase (CSP) based on Cel7A mutant D214N were resolved into enantioselective and non- selective binding. The enantioselective binding was weaker for both enantiomers on D214N-CSP than on wild-type-CSP.

Cellobiohydrolase 58 (P.c. Cel 7D) is complementary to the homologous CBH I (T.r. Cel 7A) in enantioseparations

Cellobiohydrolase 58 (EC 3.2.1.91, P.c. Cel 7D) from Phanerochaete chrysosporium was immobilized on silica and the resulting material, CBH 58-silica, was then used as a chiral stationary phase (CSP) in liquid chromatographic separations of enantiomers. The enantioselectivities obtained on CBH 58-silica were compared with those on CBH I-silica (a phase based on a corresponding cellulase from Trichoderma reesei). CBH 58-silica displayed higher selectivity than CBH I-silica for the more hydrophilic compounds, such as atenolol and metoprolol, although great similarities in chiral separation of beta-adrenergic antagonists were found between the two phases. None of the acidic compounds tested could be resolved on the CBH 58 phase. Moreover, the solutes were retained more on the CBH 58 phase in general, indicating an improved application potential in bioanalysis. Addition of cellobiose or lactose, both of which are inhibitors of cellulases, to the mobile phase impaired the enantioselectivity, indicating an overlap of the enantioselective and catalytic sites. The chiral analytes also functioned as competitive inhibitors and their inhibition constants were determined.

Discrimination between enantioselective and non-selective binding sites on cellobiohydrolase-based stationary phases by site specific competing ligands

A systematic study was performed to investigate the influence of cellobiose or lactose on the enantioselective retention behaviour of some beta-blockers in liquid chromatography using Cellobiohydrolase (CHB) I from Trichoderma reesei or Cellobiohydrolase 58 from Phanerochaete chrysosporium immobilized on silica as stationary phases. The results revealed that the retention could be described by the function [equation; see text] where the observed capacity factor corresponds to the sum of an enantioselective mode being influenced by a site specific competing ligand (competitor) and a non-selective mode unaffected by the competitor. A non-constrained non-linear least-square regression gave in all cases virtually identical nondisplacable capacity factors (k'ns) for both enantiomers of the same drug. The experimental capacity factors (k'(x,C)) of the enantiomers all show a close fit to the adapted function. The Kd values calculated for the competitor were also virtually identical for each pair of enantiomers and were in accordance with Ki data determined for the competitors in classical enzyme kinetics experiments, demonstrating that one unique site; namely, the catalytic site, was responsible for the enantioselective binding. Similar results were obtained with the resolution of rac-alprenolol and rac-metoprolol on CBH I phase.

Continuous beds for microchromatography: chromatofocusing and anion exchange chromatography

A method was developed for the preparation of continuous beds derivatized with polyethyleneimine (PEI) for chromatofocusing and anion exchange chromatography in the capillary mode. First, a continuous bed activated by epoxy groups was synthesized inside a fused silica capillary and became at the same time covalently attached to the inner wall of the capillary. A PEI solution was then pumped through the continuous bed to allow the imine groups in PEI to react with the epoxy groups in the bed. Efficient immobilization of PEI was indicated by the high-resolution separation of standard proteins (hemoglobins C, S, F, and A) in both chromatofocusing and anion exchange chromatography on a capillary column prepared by this method.

Endoglucanase 28 (Cel12A), a new Phanerochaete chrysosporium cellulase

A 28-kDa endoglucanase was isolated from the culture filtrate of Phanerochaete chrysosporium strain K3 and named EG 28. It degrades carboxymethylated cellulose and amorphous cellulose, and to a lesser degree xylan and mannan but not microcrystalline cellulose (Avicel). EG 28 is unusual among cellulases from aerobic fungi, in that it appears to lack a cellulose-binding domain and does not bind to crystalline cellulose. The enzyme is efficient at releasing short fibres from filter paper and mechanical pulp, and acts synergistically with cellobiohydrolases. Its mode of degrading filter paper appears to be different to that of endoglucanase I from Trichoderma reesei. Furthermore, EG 28 releases colour from stained cellulose beads faster than any other enzyme tested. Peptide mapping suggests that it is not a fragment of another known endoglucanases from P. chrysosporium and peptide sequences indicate that it belongs to family 12 of the glycosyl hydrolases. EG 28 is glycosylated. The biological function of the enzyme is discussed, and it is hypothesized that it is homologous to EG III in Trichoderma reesei and the role of the enzyme is to make the cellulose in wood more accessible to other cellulases.

Assessment of functional ability in patients with scleroderma: a proposed new disability assessment instrument

OBJECTIVE

To develop a simple assessment of functional ability in patients with scleroderma and to examine its reliability both as a patient self-administered instrument and when administered by a trained observer.

METHODS

An 11 item, 4 grade, functional assessment questionnaire was developed after extensive consultation with patients, physiotherapists (PT), and occupational therapists (OT) with the aim of including all functional areas of relevance. The instrument was self-administered by patients after an interval of 7 days. In the interval, the patients were assessed using the same instrument by direct observation from both a PT and an OT. Forty-seven patients with scleroderma, of varying severity, were recruited from 2 centers. Results were similar for both centers and data were pooled for analysis.

RESULTS

Agreement between the patients' first and 2nd assessment was good for all questions (estimated kappas 0.69 to 0.94) with no evidence of an order effect. Agreement was also good between therapists (estimated kappas 0.47 to 0.81). There was poor agreement between patients and therapists, with patients rating their disability substantially higher compared to the standardized therapist assessment.

CONCLUSION

This assessment schedule has high face and content validity and has excellent reliability both between trained therapists and within patients over a short time period. Its administration either as a self-report or by a therapist depends, in part, on the type of investigation undertaken.

The active sites of cellulases are involved in chiral recognition: a comparison of cellobiohydrolase 1 and endoglucanase 1

The cellulases cellobiohydrolase 1 (CBH 1) and endoglucanase 1 (EG 1) from the fungus Trichoderma reesei are closely related with 40% sequence identity and very similar in structure. In CBH 1 the active site is enclosed by long loops and some antiparallel beta-strands forming a 40 A long tunnel, whereas in EG 1 part of those loops are missing so that the enzyme has a more common active site groove. Both enzymes were immobilized on silica and these materials were used as chiral stationary phases for chromatographic separation of the enantiomers of two chiral drugs, propranolol and alprenolol. The CBH 1 phase showed much better resolution than did the EG 1 phase, suggesting that the tunnel structure of the protein may play an important role in the chiral separation. The chiral compounds were found to be competitive inhibitors of both enzymes when p-nitrophenyl lactoside (pNPL) was used as substrate. (S)-enantiomers showed stronger inhibitory effects and also longer retention time on the stationary phases than the (R)-enantiomers. The consistency between kinetic data and retention on the stationary phases clearly shows that the enzymatically active sites of CBH 1 and EG 1 are involved in chiral recognition.

Fine needle biopsy as a method for following ploidy changes in the Dunning R-3327 rat prostate tumour

The use of fine needle biopsies for the collection of cells for flow cytometry was investigated using the Altman Dunning R-3327 rat prostate tumour. Five rats were castrated 150 days after tumour implantation. Multiple fine needle biopsies were performed 138, 194 and 220 days post implantation and the results compared to those from intact animals. A small aneuploid peak was found at the 2.8c position in intact animals. Although tumour growth was slowing down in castrates, indicating hormone independency but sensitivity, no change in flow cytometric profile could be demonstrated. This indicates that, in this model, no correlation between aneuploidy and hormone independence exists. The fine needle biopsy method proved to be easy and reliable for tumours of above 1 cm3 in volume.