The home environment and childhood obesity in low-income households: indirect effects via sleep duration and screen time

Background Childhood obesity disproportionally affects children from low-income households. With the aim of informing interventions, this study examined pathways through which the physical and social home environment may promote childhood overweight/obesity in low-income households. Methods Data on health behaviors and the home environment were collected at home visits in low-income, urban households with either only normal weight (n = 48) or predominantly overweight/obese (n = 55) children aged 6–13 years. Research staff conducted comprehensive, in-person audits of the foods, media, and sports equipment in each household. Anthropometric measurements were collected, and children’s physical activity was assessed through accelerometry. Caregivers and children jointly reported on child sleep duration, screen time, and dietary intake of foods previously implicated in childhood obesity risk. Path analysis was used to test direct and indirect associations between the home environment and child weight status via the health behaviors assessed. Results Sleep duration was the only health behavior associated with child weight status (OR = 0.45, 95% CI: 0.27, 0.77), with normal weight children sleeping 33.3 minutes/day longer on average than overweight/obese children. The best-fitting path model explained 26% of variance in child weight status, and included paths linking chaos in the home environment, lower caregiver screen time monitoring, inconsistent implementation of bedtime routines, and the presence of a television in children’s bedrooms to childhood overweight/obesity through effects on screen time and sleep duration. Conclusions This study adds to the existing literature by identifying aspects of the home environment that influence childhood weight status via indirect effects on screen time and sleep duration in children from low-income households. Pediatric weight management interventions for low-income households may be improved by targeting aspects of the physical and social home environment associated with sleep

The natural history and management of hamstring injuries

Hamstring injuries in sport can be debilitating. The anatomical complexity of this muscle makes uniform assessment of injury epidemiology difficult and insures that post-injury management strategies must be individually focused. This article reviews the anatomy of the hamstring, its role in athletic movement, common mechanisms of injury, and management guidelines with the goal of return into sporting activity in mind

Dissection of mammalian orthoreovirus µ2 reveals a self-associative domain required for binding to microtubules but not to factory matrix protein µNS

Mammalian orthoreovirus protein μ2 is a component of the viral core particle. Its activities include RNA binding and hydrolysis of the γ-phosphate from NTPs and RNA 5´-termini, suggesting roles as a cofactor for the viral RNA-dependent RNA polymerase, λ3, first enzyme in 5´-capping of viral plus-strand RNAs, and/or prohibitory of RNA-5´-triphosphate-activated antiviral signaling. Within infected cells, μ2 also contributes to viral factories, cytoplasmic structures in which genome replication and particle assembly occur. By associating with both microtubules (MTs) and viral factory matrix protein μNS, μ2 can anchor the factories to MTs, the full effects of which remain unknown. In this study, a protease-hypersensitive region allowed μ2 to be dissected into two large fragments corresponding to residues 1–282 and 283–736. Fusions with enhanced green fluorescent protein revealed that these amino- and carboxyl-terminal regions of μ2 associate in cells with either MTs or μNS, respectively. More exhaustive deletion analysis defined μ2 residues 1–325 as the minimal contiguous region that associates with MTs in the absence of the self-associating tag. A region involved in μ2 self-association was mapped to residues 283–325, and self-association involving this region was essential for MT-association as well. Likewise, we mapped that μNS-binding site in μ2 relates to residues 290–453 which is independent of μ2 self-association. These findings suggest that μ2 monomers or oligomers can bind to MTs and μNS, but that self-association involving μ2 residues 283–325 is specifically relevant for MT-association during viral factories formation

From Molecular Genetics to Phylodynamics: Evolutionary Relevance of Mutation Rates Across Viruses

Although evolution is a multifactorial process, theory posits that the speed of molecular evolution should be directly determined by the rate at which spontaneous mutations appear. To what extent these two biochemical and population-scale processes are related in nature, however, is largely unknown. Viruses are an ideal system for addressing this question because their evolution is fast enough to be observed in real time, and experimentally-determined mutation rates are abundant. This article provides statistically supported evidence that the mutation rate determines molecular evolution across all types of viruses. Properties of the viral genome such as its size and chemical composition are identified as major determinants of these rates. Furthermore, a quantitative analysis reveals that, as expected, evolution rates increase linearly with mutation rates for slowly mutating viruses. However, this relationship plateaus for fast mutating viruses. A model is proposed in which deleterious mutations impose an evolutionary speed limit and set an extinction threshold in nature. The model is consistent with data from replication kinetics, selection strength and chemical mutagenesis studies

A new short uncemented, proximally fixed anatomic femoral implant with a prominent lateral flare: design rationals and study design of an international clinical trial

<p>Abstract</p> <p>Background</p> <p>Anatomic short femoral prostheses with a prominent lateral flare have the potential to reduce stress-shielding in the femur through a more physiological stress distribution to the proximal femur. We present the design rationale of a new short uncemented, proximally fixed anatomic femoral implant and the study design of a prospective multi-centre trial to collect long-term patient outcome and radiographic follow up data.</p> <p>Methods</p> <p>A prospective surveillance study (trial registry NCT00208555) in four European centres (UK, Italy, Spain and Germany) with a follow up period of 15 years will be executed. The recruitment target is 200 subjects, patients between the ages of 18 and 70 admitted for primary cementless unilateral THA will be included. The primary objective is to evaluate the five-year survivorship of the new cementless short stem. The secondary objectives of this investigation are to evaluate the long term survivorship and the clinical performance of the implant, the impact on the subjects health related Quality of Life and the affect of the prosthesis on bone mineral density. Peri- and postoperative complications will be registered. Clinical and radiographic evaluation of prosthesis positioning will be done post-operatively and at 3, 6, 12, 24, 60, 120 and 180 months follow up.</p> <p>Discussion</p> <p>Shortening of the distal stem can maximise bone and soft tissue conservation. New stem types have been designed to improve the limitations of traditional implants in primary THA. A new, uncemented femoral short stem is introduced in this paper. A long-term follow up study has been designed to verify stable fixation and to research into the clinical outcome. The results of this trial will be presented as soon as they become available.</p

Physician practices related to use of BMI-for-age and counseling for childhood obesity prevention: A cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Screening for obesity and providing appropriate obesity-related counseling in the clinical setting are important strategies to prevent and control childhood obesity. The purpose of this study is to document pediatricians (PEDs) and general practitioners (GPs) with pediatric patients use of BMI-for-age to screen for obesity, confidence in explaining BMI, access to referral clinics, and characteristics associated with screening and counseling to children and their caregivers.</p> <p>Methods</p> <p>The authors used 2008 DocStyles survey data to examine these practices at every well child visit for children aged two years and older. Counseling topics included: physical activity, TV viewing time, energy dense foods, fruits and vegetables, and sugar-sweetened beverages. Chi-square tests were used to examine differences in proportions and logistic regression to identify characteristics associated with screening and counseling.</p> <p>Results</p> <p>The final analytic sample included 250 PEDs and 621 GPs. Prevalence of using BMI-for-age to screen for obesity at every well child visit was higher for PEDs than GPs (50% vs. 22%, χ2 = 67.0, p ≤ 0.01); more PEDs reported being very/somewhat confident in explaining BMI (94% vs. GPs, 87%, p < 0.01); more PEDs reported access to a pediatric obesity specialty clinic for referral (PEDs = 65% vs. GPs = 42%, χ2 = 37.5, p ≤ 0.0001).</p> <p>In general, PEDs reported higher counseling prevalence than GPs. There were significant differences in the following topics: TV viewing (PEDs, 79% vs. GPs, 61%, χ2 = 19.1, p ≤ 0.0001); fruit and vegetable consumption (PEDs, 87% vs. GPs, 78%, χ2 = 6.4, p ≤ 0.01). The only characteristics associated with use of BMI for GPs were being female (OR = 2.3, 95% CI = 1.5-3.5) and serving mostly non-white patients (OR = 1.8, 95% CI = 1.1-2.9); there were no significant associations for PEDs.</p> <p>Conclusions</p> <p>The findings for use of BMI-for-age, counseling habits, and access to a pediatric obesity specialty clinic leave room for improvement. More research is needed to better understand why BMI-for-age is not being used to screen at every well child visit, which may increase the likelihood overweight and obese patients receive counseling and referrals for additional services. The authors also suggest more communication between PEDs and GPs through professional organizations to increase awareness of existing resources, and to enhance access and referral to pediatric obesity specialty clinics.</p

Activation of Human T-Helper/Inducer Cell, T-Cytotoxic Cell, B-Cell, and Natural Killer (NK)-Cells and induction of Natural Killer Cell Activity against K562 Chronic Myeloid Leukemia Cells with Modified Citrus Pectin

<p>Abstract</p> <p>Background</p> <p>Modified citrus pectin (MCP) is known for its anti-cancer effects and its ability to be absorbed and circulated in the human body. In this report we tested the ability of MCP to induce the activation of human blood lymphocyte subsets like T, B and NK-cells.</p> <p>Methods</p> <p>MCP treated human blood samples were incubated with specific antibody combinations and analyzed in a flow cytometer using a 3-color protocol. To test functionality of the activated NK-cells, isolated normal lymphocytes were treated with increasing concentrations of MCP. Log-phase PKH26-labeled K562 leukemic cells were added to the lymphocytes and incubated for 4 h. The mixture was stained with FITC-labeled active form of caspase 3 antibody and analyzed by a 2-color flow cytometry protocol. The percentage of K562 cells positive for PKH26 and FITC were calculated as the dead cells induced by NK-cells. Monosaccharide analysis of the MCP was performed by high-performance anion-exchange chromatography with pulse amperometric detection (HPAEC-PAD).</p> <p>Results</p> <p>MCP activated T-cytotoxic cells and B-cell in a dose-dependent manner, and induced significant dose-dependent activation of NK-cells. MCP-activated NK-cells demonstrated functionality in inducing cancer cell death. MCP consisted of oligogalacturonic acids with some containing 4,5-unsaturated non-reducing ends.</p> <p>Conclusions</p> <p>MCP has immunostimulatory properties in human blood samples, including the activation of functional NK cells against K562 leukemic cells in culture. Unsaturated oligogalacturonic acids appear to be the immunostimulatory carbohydrates in MCP.</p

Urinary C-Peptide Measurement as a Marker of Nutritional Status in Macaques

Studies of the nutritional status of wild animals are important in a wide range of research areas such as ecology, behavioural ecology and reproductive biology. However, they have so far been strongly limited by the indirect nature of the available non-invasive tools for the measurement of individual energetic status. The measurement of urinary C-peptide (UCP), which in humans and great apes shows a close link to individual nutritional status, may be a more direct, non-invasive tool for such studies in other primates as well and possibly even in non-primate mammals. Here, we test the suitability of UCPs as markers of nutritional status in non-hominid primates, investigating relationships between UCPs and body-mass-index (BMI), skinfold fatness, and plasma C-peptide levels in captive and free-ranging macaques. We also conducted a food reduction experiment, with daily monitoring of body weight and UCP levels. UCP levels showed significant positive correlations with BMI and skinfold fatness in both captive and free-ranging animals and with plasma C-peptide levels in captive ones. In the feeding experiment, UCP levels were positively correlated with changes in body mass and were significantly lower during food reduction than during re-feeding and the pre-experimental control condition. We conclude that UCPs may be used as reliable biomarkers of body condition and nutritional status in studies of free-ranging catarrhines. Our results open exciting opportunities for energetic studies on free-ranging primates and possibly also other mammals

Rhinovirus Genome Variation during Chronic Upper and Lower Respiratory Tract Infections

Routine screening of lung transplant recipients and hospital patients for respiratory virus infections allowed to identify human rhinovirus (HRV) in the upper and lower respiratory tracts, including immunocompromised hosts chronically infected with the same strain over weeks or months. Phylogenetic analysis of 144 HRV-positive samples showed no apparent correlation between a given viral genotype or species and their ability to invade the lower respiratory tract or lead to protracted infection. By contrast, protracted infections were found almost exclusively in immunocompromised patients, thus suggesting that host factors rather than the virus genotype modulate disease outcome, in particular the immune response. Complete genome sequencing of five chronic cases to study rhinovirus genome adaptation showed that the calculated mutation frequency was in the range observed during acute human infections. Analysis of mutation hot spot regions between specimens collected at different times or in different body sites revealed that non-synonymous changes were mostly concentrated in the viral capsid genes VP1, VP2 and VP3, independent of the HRV type. In an immunosuppressed lung transplant recipient infected with the same HRV strain for more than two years, both classical and ultra-deep sequencing of samples collected at different time points in the upper and lower respiratory tracts showed that these virus populations were phylogenetically indistinguishable over the course of infection, except for the last month. Specific signatures were found in the last two lower respiratory tract populations, including changes in the 5′UTR polypyrimidine tract and the VP2 immunogenic site 2. These results highlight for the first time the ability of a given rhinovirus to evolve in the course of a natural infection in immunocompromised patients and complement data obtained from previous experimental inoculation studies in immunocompetent volunteers