Resistance training responses across race and ethnicity: a narrative review.

OBJECTIVES: Although the physiological mechanisms are not fully understood, race/ethnicity differences vary across cardiometabolic disease risk factors. Resistance training (RT) is an effective therapy for improving these risk factors in addition to body composition and physical performance. Thus, the purpose of this study was to determine the effects of RT over time on different racial and ethnic populations across cardiometabolic, body composition, and physical performance outcomes. DESIGN: Electronic databases Scopus and PubMed were searched for studies that compared different racial/ethnic responses to RT across cardiometabolic, body composition, and physical performance parameters. Inclusion criteria for the studies were as follows: (1) published in the English language; (2) compared races or ethnicities across cardiometabolic risk factors, body composition, or physical performance variables following a RT intervention; (3) included adults 18 years or older, and (4) included an isolated RT intervention group. RESULTS: Nine studies were found that met the inclusion criteria. The identified studies involved cohorts of White American (WA), South Asian, European Chilean, Mapuche Chilean, White Scottish, and African American (AA) males and females. Race/ethnicity differences following a RT intervention were found for fat-free mass preservation and changes in blood pressure, endothelial function, brachial artery stiffness, cardiac autonomic function, inflammatory and oxidative stress markers, insulin sensitivity, body mass index, waist circumference, % body fat, and muscular strength. With the exception of changes in systolic blood pressure and brachial artery stiffness, AAs consistently showed more beneficial adaptations compared to WAs to RT across studies. CONCLUSION: Race and ethnicity play a role in how adults adapt to chronic RT. These data may aid in better understanding the social, biological, and environmental factors that likely influenced these racial/ethnic differences in response to RT, assist in creating tailored exercise prescriptions for various racial/ethnic populations, and inform policies for determining resource allocations to address health inequities.

A tyrosine phosphoregulatory system controls exopolysaccharide biosynthesis and biofilm formation in Vibrio cholerae.

Production of an extracellular matrix is essential for biofilm formation, as this matrix both secures and protects the cells it encases. Mechanisms underlying production and assembly of matrices are poorly understood. Vibrio cholerae, relies heavily on biofilm formation for survival, infectivity, and transmission. Biofilm formation requires Vibrio polysaccharide (VPS), which is produced by vps gene-products, yet the function of these products remains unknown. Here, we demonstrate that the vps gene-products vpsO and vpsU encode respectively for a tyrosine kinase and a cognate tyrosine phosphatase. Collectively, VpsO and VpsU act as a tyrosine phosphoregulatory system to modulate VPS production. We present structures of VpsU and the kinase domain of VpsO, and we report observed autocatalytic tyrosine phosphorylation of the VpsO C-terminal tail. The position and amount of tyrosine phosphorylation in the VpsO C-terminal tail represses VPS production and biofilm formation through a mechanism involving the modulation of VpsO oligomerization. We found that tyrosine phosphorylation enhances stability of VpsO. Regulation of VpsO phosphorylation by the phosphatase VpsU is vital for maintaining native VPS levels. This study provides new insights into the mechanism and regulation of VPS production and establishes general principles of biofilm matrix production and its inhibition.

Dimethyl sulfoxide for cryopreservation of alginate encapsulated liver cell spheroids in bioartificial liver support; assessments of cryoprotectant toxicity tolerance and dilution strategies.

The Bioartificial Liver (BAL) is an extra-corporeal liver support designed to support the function of the Liver in patients with impaired liver function. The BAL biomass consists of alginate encapsulated liver spheroids (AELS). To facilitate rapid delivery of a BAL to patients the AELS are cryopreserved using a DMSO-containing cryoprotectant solution. This study assesses toxicity of DMSO in AELS at concentrations and temperatures relevant to the cryopreservation and recovery process of a cellular biomass. Additionally, it develops a process to remove DMSO from AELS before delivery of cell product to patients. Exposure of AELS to DMSO, at a concentration of 12% (v/v) for 10 min did not have a negative effect on the viability of the AELS up to 24 h after exposure, irrespective of the exposure temperature between 37 C and 0 C. Evidence of toxicity was only seen with exposure to 40% (v/v) DMSO, which was more notable at warm temperatures. Post-Thaw removal of DMSO was measured by determining the DMSO concentration of the post-thaw washes using refractometry. Washing AELS 3 times in tapering concentrations of Glucose supplemented DMEM at an AELS:wash ratio of 1:2 was sufficient to reduce DMSO to undetectable levels (<1%). The study demonstrated that the thawing method minimised DMSO toxicity to the BAL biomass, and the post-thaw washing protocol successfully removed all the DMSO present in the cryopreserved BAL. Thereby enabling effective cryopreservation of the BAL for future clinical translation.

Utility of three anthropometric indices in assessing the cardiometabolic risk profile in children.

OBJECTIVES: To evaluate the ability of BMI, WC, and WHtR to identify increased cardiometabolic risk in pre-adolescents. METHODS: This is a cross-sectional study involving 192 children (10.92 ± 0.58 years, 56% female) from the United Kingdom between 2010 and 2013. Receiver operating characteristic curves determined the discriminatory ability of BMI, WC and WHtR to identify individuals with increased cardiometabolic risk (increased clustered triglycerides, HDL-cholesterol, systolic blood pressure, cardiorespiratory fitness, and glucose). RESULTS: A WHtR ≥ 0.5 increased the odds by 5.2 (95% confidence interval 2.6 - 10.3) of having increased cardiometabolic risk. Similar associations were observed for BMI and WC. Both BMI-z and WHtR were fair predictors of increased cardiometabolic risk, although BMI-z demonstrated the best trade-off between sensitivity and specificity, 76.1% and 63.6%, compared with 68.1% and 65.5% for WHtR. Cross-validation analysis revealed that BMI-z and WHtR correctly classified 84% of individuals (kappa score = 0.671, 95% CI 0.55, 0.79). The sensitivity of the cut-points suggests that 89.3% of individuals were correctly classified as being at risk with only 10.7% misdiagnosed whereas the specificity of the cut-points indicated that 77.8% of individuals were correctly identified as being healthy with 22.2% of individuals incorrectly diagnosed as being at risk. CONCLUSIONS: Findings suggest that WHtR provides similar cardiometabolic risk estimates to age and sex adjusted BMI.

A criterion-referenced assessment is needed for measuring child obesity.

Body Mass Index (BMI), as an adiposity indicator, assumes that for any given height a change in weight is attributed to a change in fat. This seems problematic in growing youth as great divergence is evident in bone, muscle, and adipose tissue development. Secondly, use of reference populations in categorizing children based on BMI, frequently use arbitrary percentile cut-offs for obesity and do not meet all of the assumptions that cut-offs imply. Lastly, BMI does not control for maturation status. Criterion-referenced assessments of child obesity that account for abdominal adiposity and permit international comparisons, such as waist-to-height ratio (WtHR), must be considered. Better predictive utility has been demonstrated when using WtHR for abdominal adiposity and cardiovascular risk factors in youth compared with BMI. Although multiple methods for assessing waist circumference may be problematic for comparison purposes, its simplicity and international comparability aspects make it a promising alternative to BMI.

Human placental organoids as a model to probe early gestation maternal immune dynamics.

During pregnancy, the human placenta establishes tolerance toward fetal allogeneic tissue, where specialized trophoblast subtypes play a complex role in local and peripheral immunomodulation. However, due to inadequate models to study the early gestation of the human placenta, each trophoblast subtype's role in modulating the maternal immune response has remained elusive. Here, we derived human placental organoids from early gestation trophoblast stem cells to (1) identify patterns of immunomodulatory protein expression by trophoblast subtype and (2) evaluate the effects of the placental organoid secretome on immune cell activation and regulation. We show that the three primary trophoblast phenotypes had distinct influences on immune cell phenotype and activation and that three-dimensional culture significantly alters trophoblast immunomodulation relative to traditional two-dimensional trophoblast culture.

Incidence and Risks of HIV Infection, Medication Options, and Adverse Effects in Accidental Needle Stick Injuries: A Narrative Review.

Accidental needle sticks can lead to infections, including HIV. As scientists have learned more about HIV and its replicative physiology, identification of target sites and novel medications have been developed. HIV is spread throughout the population through contact with blood, semen, and rectal or vaginal secretions of infected individuals. Therefore, it is important in general for healthcare workers to be aware of its transmission modes and ways to minimize exposure. In this regard, even with hospitals providing education, training, and safety protocols, there is a continued infection spread with HIV, especially by accidental needle sticks. There is also a wide variety of testing that can be used for HIV utilizing different methodologies, allowing for improved measurement of infection status. Any person with HIV should be tested to clarify infection status and be educated to minimize future virus spread. The current CDC recommendations for HIV infection treatment are antiretroviral therapies, such as an HIV postexposure prophylaxis regimen, which consists of a cocktail of antiretrovirals and postexposure prophylaxis immediately for occupational exposures, such as accidental needlestick exposure from an HIV infected patient. To decrease accidental HIV stick injuries, there are safety precautions in place, that if followed, would help reduce this incidence. HIV accidental needle stick injuries still happen in the hospital workplace, but with proper education and treatment, if exposed, there is hope to minimize the effects.

Topical Cocaine Hydrochloride Nasal Solution: Anesthetic and Surgical Considerations.

Adequate surgical view during various types of nasal procedures is essential for surgical operations to be performed in a safe, efficient, and successful manner. Minimizing bleeding during surgery is an important way of increasing visualization that is commonly achieved by using a vasoconstrictive agent to control intraoperative hemorrhage. Many otolaryngologists choose to employ topical cocaine to minimize bleeding during surgery owing to its vasoconstrictive properties, while simultaneously benefitting from its dual local anesthetic effects. The relative benefit of topical cocaine for otolaryngologic procedures when compared to other topical analgesics and vasoconstrictors remains a topic of discussion due to the multiple potential cardiac and central nervous system side effects associated with cocaine administration. Furthermore, there is not a scientifically backed maximal safe dose published; instead, most of the guidelines for intranasal cocaine use are based on untested clinical practice. Despite this, the short latency, adequate duration of action, and inherent vasoconstrictive and decongestive capabilities make cocaine a valuable anesthetic agent for use in clinical procedures. As the relative benefit of using topical cocaine compared to the use of other vasoconstrictors and analgesics for nasal procedures remains undetermined in the current literature, this leaves the need for a comprehensive review of research that explores the risks and benefits of using topical cocaine in nasal procedures based on clinical trials that compare intranasal cocaine with various other analgesics and vasoconstrictors.

Metabolic syndrome: Operational definitions and aerobic and resistance training benefits on physical and metabolic health in children and adolescents.

BACKGROUND: The variation in parameters for childhood metabolic syndrome (MetS) has hindered the development of a consensus for the diagnostic criteria in this group. Despite these inconsistencies, it is accepted that exercise can ameliorate the deleterious effects of MetS. However, direct comparison between aerobic versus resistance exercise on MetS symptomology in adolescents is lacking. AIM: Aim of this review was to discuss controversies associated with current MetS operation definitions in adolescents and present a review summarizing longitudinal studies relevant to the influence of aerobic and resistance training on children with MetS. METHODS: Reviews of PubMed and Web of Science were conducted to identify literature focusing on the influence of aerobic and resistance training on children with MetS. Selected manuscripts featured longitudinal research only. RESULTS: A universally accepted definition of MetS for the pediatric population has yet to be established. As such, consensus regarding diagnostic criteria for MetS among children is lacking despite the presence of various descriptions in the literature. Though studies support the importance of aerobic and resistance exercise to combat comorbidities associated with MetS, longitudinal studies investigating the benefits of each exercise type among adolescents are limited and inconsistent. CONCLUSION: An improved understanding of the impact of aerobic and resistance training on children with MetS is clinically relevant because it may facilitate more appropriate exercise recommendations for children with MetS. Additional large cohort studies are warranted to determine optimal exercise type.

Age-Associated Changes to Lymph Node Fibroblastic Reticular Cells.

The decreased proportion of antigen-inexperienced, naïve T cells is a hallmark of aging in both humans and mice, and contributes to reduced immune responses, particularly against novel and re-emerging pathogens. Naïve T cells depend on survival signals received during their circulation among the lymph nodes by direct contacts with stroma, in particular fibroblastic reticular cells. Macroscopic changes to the architecture of the lymph nodes have been described, but it is unclear how lymph node stroma are altered with age, and whether these changes contribute to reduced naïve T cell maintenance. Here, using 2-photon microscopy, we determined that the aged lymph node displayed increased fibrosis and correspondingly, that naïve T-cell motility was impaired in the aged lymph node, especially in proximity to fibrotic deposition. Functionally, adoptively transferred young naïve T-cells exhibited reduced homeostatic turnover in aged hosts, supporting the role of T cell-extrinsic mechanisms that regulate their survival. Further, we determined that early development of resident fibroblastic reticular cells was impaired, which may correlate to the declining levels of naïve T-cell homeostatic factors observed in aged lymph nodes. Thus, our study addresses the controversy as to whether aging impacts the composition lymph node stroma and supports a model in which impaired differentiation of lymph node fibroblasts and increased fibrosis inhibits the interactions necessary for naïve T cell homeostasis.

Effectiveness of Resistance Training and Associated Program Characteristics in Patients at Risk for Type 2 Diabetes: a Systematic Review and Meta-analysis.

BACKGROUND: Resistance training (RT) is an effective intervention for glycemic control and cardiometabolic health in individuals with type 2 diabetes (T2D). However, the use of RT in individuals at risk for T2D to prevent or delay the onset of T2D, and RT program characteristics that are most effective are still unknown. The purpose of this review is to determine the effects of RT on cardiometabolic risk factors in those at risk for T2D and to examine RT program characteristics associated with intervention effectiveness. METHODS: PubMed, Cochrane, Web of Science, and Embase databases were systematically searched for published controlled trials that compared cardiometabolic outcomes in adults with cardiometabolic risk for those that underwent an RT intervention with those that did not. A systematic review and meta-analysis was conducted to determine the effect of RT on glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG), body fat percentage (BF%), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides (TG). Additional analyses examined effects of intervention duration and dietary intervention on FPG and TG. RESULTS: Fourteen trials with 668 participants were included. For RT compared to controls, the standardized mean difference (SMD) was -1.064 for HbA1c (95% confidence interval [CI] -1.802 to -0.327; p=0.005), -0.99 for FPG (95% CI -1.798 to -0.183; p=0.016), -0.933 for TC (95% CI -1.66 to -0.206; p=0.012), -0.840 for BF% (95% CI -1.429 to -0.251; p=0.005), -0.693 for HDL (95% CI -1.230 to -0.156; p=0.011), -1.03 for LDL (95% CI -2.03 to -0.050; p=0.039), and -0.705 for TG (95% CI -1.132 to -0.279; p=0.001). CONCLUSIONS: RT is beneficial for improving glycemic control, BF%, and blood lipids in those at risk for diabetes. The addition of a dietary component did not result in larger reductions in FPG and TG than RT alone. PROSPERO REGISTRATION ID: CRD42019122217.

Effects of High-Intensity Interval Training Protocols on Liver Enzymes and Wellness in Women.

BACKGROUND: Single-modality, high-intensity interval training (HIIT) using traditional cardiorespiratory exercise selection has been found to provide similar and sometimes superior cardiometabolic effects compared with moderate-intensity continuous training. However, little is known regarding the cardiometabolic and psychosocial effects of HIIT using resistance training modalities. Therefore, this study aims to compare the effects of HIIT using rowing (R-HIIT) and multimodal HIIT (MM-HIIT) using resistance training on liver enzymes, cardiometabolic risk factors, and psychosocial outcomes. METHOD: Recreationally active females with a body mass index <30 kg/m2 (N = 16, 23.0 ± 5.9 years) were randomized into a MM-HIIT or R-HIIT group and completed a 12-week HIIT intervention (ClinicalTrials.gov registration number: https://clinicaltrials.gov/ct2/show/NCT03093441) using principles of social cognitive theory (SCT). Participants completed pre- and postintervention measurements on anthropometrics, resting heart rate, blood pressure, blood measures (lipids, liver enzymes, and glucose), exercise self-efficacy, and perceived wellness. Analysis of covariance was used to examine differences in postintervention measures between groups after controlling for baseline values, waist circumference, and waist-to-height ratio. RESULTS: R-HIIT group had significantly decreased alanine aminotransferase (mean difference = 13.16, P=0.013, effect size (ES) = 0.44, confidence interval (CI) = 3.40 to 22.92) and aspartate aminotransferase (mean difference = 10.79, P=0.024, ES = 0.38, CI = 1.67 to 19.90) levels compared with the M-HIIT group, and the whole group had improved wellness scores (14.72 ± 2.6 to 16.89 ± 2.76, P=0.002). CONCLUSION: R-HIIT may be an effective preventative method for improving liver health in females without obesity. When using principles of SCT, HIIT may enhance overall well-being.

Effects of single bout resistance exercise on glucose levels, insulin action, and cardiovascular risk in type 2 diabetes: A narrative review.

AIMS: Previous studies have reported beneficial effects of chronic resistance exercise in the prevention and treatment of type 2 diabetes. To clarify potential modulators of acute responses to resistance exercise, we reviewed the literature to determine the effects of a single bout of resistance exercise on cardiometabolic risk factors in type 2 diabetes. METHODS: Pubmed and Embase were searched for studies investigating the effects of single bouts of resistance exercise on glucose and insulin levels, and cardiovascular disease risk in people with diabetes. Fourteen reports were identified and reviewed to formulate evidence-based resistance exercise prescription recommendations. RESULTS: Glucose and insulin levels appear to decrease with resistance exercise with effects lasting up to 24 and 18 h, respectively. Bouts of resistance exercise may outperform aerobic exercise in reducing ambulatory blood pressure, with effects lasting up to 24 h. Moreover, resistance exercise after rather than before a meal may be more effective in reducing glucose, insulin, and triacylglycerol levels. However, reducing injectable insulin dosage prior to resistance exercise may blunt its favorable effects on glucose levels. CONCLUSIONS: This review suggests that a single bout of resistance exercise may be effective for acutely improving cardiometabolic markers in people with diabetes.

Grip Strength Cut Points for Diabetes Risk Among Apparently Healthy U.S. Adults.

INTRODUCTION: Early detection screening tools are needed to aid in preventing vascular complications associated with type 2 diabetes. As low muscular strength is linked to increased diabetes risk, the purpose of this study is to establish muscular strength cut points for determining diabetes risk using a large, nationally representative U.S. METHODS: Using the 2011-2012 and 2013-2014 National Health and Nutrition Examination Survey data, 5,108 participants aged 20-80 years (68.6% aged 20-50 years; young male participants, n=1,813, mean age=33.43 years; young female participants, n=1,692, mean age=33.39 years; older male participants, n=813, mean age=59.92 years; older female participants, n=790, mean age=60.45 years) and free of common diabetes comorbidities were included. Muscular strength was assessed using a handgrip dynamometer and normalized by adjusting for body weight. A logistic regression for survey data controlling for covariates was used to determine normalized grip strength cut points. Diabetes risk was determined using American Diabetes Association diagnostic criteria. Analyses were conducted in the summer of 2019. RESULTS: Normalized grip strength significantly predicted diabetes (p=0.0332), and the cut points for detecting diabetes risk included 0.78 (young male participants), 0.57 (young female participants), 0.68 (older male participants), and 0.49 (older female participants). The risk percentages for diabetes and estimated rates reported for all subgroups were comparable, and the risk percentages included 6.84 (95% CI=5.32, 8.36; younger male participants), 7.49 (95% CI=5.87, 9.10; younger female participants), 5.76 (95% CI=2.34, 9.19, older male participants), and 4.27 (95% CI=2.44, 6.10; older female participants). CONCLUSIONS: Normalized grip strength using the cut points proposed in this paper may be a useful screening tool for diabetes risk in apparently healthy, normotensive adults.

Normative data for the Balance Tracking System modified Clinical Test of Sensory Integration and Balance protocol.

Purpose: Force plate balance testing technology has traditionally been underutilized in clinical and research settings due to the high cost and lack of portability. A relatively new force plate called the Balance Tracking System (BTrackS) has been developed to overcome these barriers. BTrackS recently implemented the modified Clinical Test of Sensory Integration and Balance (mCTSIB) as a means of evaluating various sources of sensory information for postural sway control. The present study aimed to provide much needed normative data for the BTrackS mCTSIB protocol. Materials and methods: Data from 604 healthy adults (308 women; 296 men) between the ages of 18 and 29 years were collected according to the BTrackS mCTSIB protocol. The protocol consisted of four, 20-second static standing trials that manipulated relative contributions of the vision, proprioception and vestibular sensory systems through various eyes open/closed and foam/no foam conditions. Comparisons of men versus women and the impact of body size (ie body mass index) were determined so that relevant percentile rankings could be calculated. Results: Analysis of variance showed an interaction between sex and task condition on the BTrackS mCTSIB (p<0.001). This interaction indicated that women outperformed men on all conditions, but especially in the fourth trial where eyes were closed and standing was done on a compliant foam surface. Percentile rankings were calculated based on sex and BTrackS mCTSIB condition. No relationship was found between BTrackS mCTSIB results and body size. Conclusion: Normative data provided in this study are vital for establishing potential sensory feedback-based balance dysfunctions that may exist clinically or in laboratory settings. In addition, this data can aid in the tracking of changes over a rehabilitation period and/or the effectiveness of balance interventions.

The Impact of Different High-Intensity Interval Training Protocols on Body Composition and Physical Fitness in Healthy Young Adult Females.

Although traditional high-intensity interval training (HIIT) has been effective in improving body composition and physical fitness, it is unclear how multimodal HIIT affects these variables. This study compared the differences between these two training programs on body composition and physical fitness in apparently healthy, nonobese young adult females. A total of 16 participants (mean age = 23 ± 5.08 years) completed a 12-week HIIT intervention with two treatment groups: rowing and multimodal. Immediately before and after the intervention, the following measures were assessed: body mass index (BMI), total body mass, waist circumference, waist-to-height ratio, total body fat %, visceral adipose tissue, lean mass, bone mineral outcomes, cardiovascular fitness, and muscular fitness. A general linear model with repeated measures was used to assess changes over time for the group as a whole, as well as between-group differences. For the group as a whole, there were significant decrease in total body fat % (p = 0.04) and significant increases in BMI (p = 0.015), total body mass (p = 0.003), lean mass (p < 0.001), bone mineral content (BMC) (p < 0.001), VO2max (p = 0.01), broad jump (p = 0.001), squat endurance (p = 0.006), press (p < 0.001), back squat (p < 0.001), and deadlift (p < 0.001) one repetition maximum (1RM). The multimodal group (p < 0.001) increased deadlift 1RM significantly more than the rowing group (p = 0.002). HIIT can be an effective means for improving cardiovascular and muscular fitness, increasing lean mass and BMC, and thereby improving cardiometabolic as well as musculoskeletal health in nonobese females. Using a multimodal approach may give the added benefit of superior muscular strength increases.

Primary School Children's Health Behaviors, Attitudes, and Body Mass Index After a 10-Week Lifestyle Intervention With Follow-Up.

Background: Given the current global child obesity epidemic, testing the effectiveness of interventions in reducing obesity and its influencers is paramount. The purpose of this study was to determine immediate and long-term changes in body mass index and psychosocial variables following a 10-week lifestyle intervention. Methods: Seven hundred and seventy participants (8.75 ± 0.98 years of age, 379 boys and 391 girls) took part in the study. Participants had height, weight, and psychosocial questionnaires assessed at pre- and post-control, pre- and post-intervention, and 6-months post-intervention. Participants completed a weekly 10-week intervention consisting of healthy eating and physical activity education, physical activity, parental involvement, and behavior change techniques. Regression models were fit with correlated errors where the correlation occurred only between time points, not between subjects, and the nesting effects of school and area deprivation were controlled. Results: Regression models revealed a significant decrease in body mass index from pre- to post-intervention of 0.8512 kg/m2 (P = 0.0182). No Changes in body mass index occurred from post-intervention to 6-month follow-up (P = 0.5446). The psychosocial variables did not significantly change. Conclusions: This lifestyle intervention may be an effective means for improving body mass index in primary school children in the short-term if the duration of the intervention is increased, but these changes may not be sustained without on-going support.

A Systematised Review of Primary School Whole Class Child Obesity Interventions: Effectiveness, Characteristics, and Strategies.

Background. A systematised review was conducted to examine the effectiveness of school-based interventions that focus on changing dietary intake and physical activity levels to reduce childhood obesity. Methods. Multiple databases were searched for randomised and nonrandomised interventions from 2007 to 2016 in full-time elementary schools, which were delivered to the whole class, included dietary and physical activity components, involved both sexes, were written in English, and used body mass index (BMI) as an outcome. Results. The database search produced 8,866 titles from which 78 were deemed relevant and assessed for inclusion resulting in 15 studies meeting all inclusion criteria. From these 15 studies, 9 yielded a reduction or stabilisation in BMI or BMI z-score in the entire intervention group and/or subgroups. Programmes lasting between 6 and 12 months that involve multiple environmental, educational, and physical strategies appear to be most likely to result in BMI or BMI z-score improvement. Moderators most likely influencing an improvement in BMI included increased physical activity, decreased sugar sweetened beverages intake, and increased fruit intake. Conclusions. School-based interventions may be an effective means for child obesity prevention. The identification of consistent elements used in school-based interventions that have demonstrated effectiveness may aid in preventing child obesity.

A Strategy for Direct Chemical Activation of the Retinoblastoma Protein.

The retinoblastoma (Rb) tumor suppressor protein negatively regulates cell proliferation by binding and inhibiting E2F transcription factors. Rb inactivation occurs in cancer cells upon cyclin-dependent kinase (Cdk) phosphorylation, which induces E2F release and activation of cell cycle genes. We present a strategy for activating phosphorylated Rb with molecules that bind Rb directly and enhance affinity for E2F. We developed a fluorescence polarization assay that can detect the effect of exogenous compounds on modulating affinity of Rb for the E2F transactivation domain. We found that a peptide capable of disrupting the compact inactive Rb conformation increases affinity of the repressive Rb-E2F complex. Our results demonstrate the feasibility of discovering novel molecules that target the cell cycle and proliferation through directly targeting Rb rather than upstream kinase activity.