Effects of supplementing colostrum beyond the first day of life on growth and health parameters of preweaning Holstein heifers.

The preweaning period for a dairy calf is characterized by high morbidity and mortality rates, leading to financial losses for producers. Identifying strategies to improve the health and welfare of calves while reducing antimicrobial use continues to be crucial to the success of the dairy industry. The objective of this study was to determine the effects of feeding colostrum replacer (CR) to dairy heifer calves beyond d 1 of life on growth, serum IgG, the incidence of diarrhea and bovine respiratory disease (BRD), and the risk of mortality in the preweaning period. At birth, Holstein heifer calves (n = 200; 50/treatment) weighing 40.7 ± 0.35 kg (mean ± SE) were fed 3.2 L of CR (205 g IgG/feeding) at 0 h and 12 h of life. Calves were then randomly assigned to 1 of 4 treatments: 450 g of milk replacer (MR) from d 2 to 14 (control, CON), 380 g of CR + 225 g of MR from d 2 to 3, then 450 g of MR from d 4 to 14 (transition, TRAN), 45 g of CR + 450 g of MR from d 2 to 14 (extended, EXT); or 380 g of CR + 225 g of MR from d 2 to 3, then 45 g of CR + 450 g of MR from d 4 to 14 (transition + extended, TRAN+EXT). Each treatment was reconstituted to 3 L and fed twice daily. All CR treatments were fed using bovine-derived CR containing 27% IgG. From d 15 to 41, all calves were fed 600 g of MR reconstituted to 4 L twice daily. Body weight was recorded at birth and every 7 d until study completion on d 49. Blood samples were taken daily until d 7 to evaluate serum IgG and then every 7 d until d 49. A health assessment was performed daily to evaluate calves for BRD and diarrhea. Data were analyzed using mixed linear regression, mixed logistic regression, and survival analysis models in SAS 9.4. Serum IgG concentrations were not affected by treatment for the study period. The EXT and TRAN+EXT groups had greater average daily gain (ADG) from d 7 to 14 (0.14 kg/d) and the TRAN group had greater ADG from d 14 to 21 (0.11 kg/d), compared with CON. There was no association of treatment with the odds or the duration of a diarrhea bout. However, provision of CR to the TRAN and EXT calves was associated with a reduced hazard of diarrhea compared with CON calves. Furthermore, TRAN and EXT calves have a lower hazard of mortality compared with CON calves, with TRAN and EXT calves had a 2.8- and 3.8-times lower hazard of mortality, respectively. Our findings suggest that the supplementation of CR to dairy calves positively affects ADG, and reduces the hazard of diarrhea and mortality during the preweaning period. Future research should look to further refine the supplementation strategy of CR to calves and explore the mechanism of action.

Effects of enriching IgG concentration in low- and medium-quality colostrum with colostrum replacer on IgG absorption in newborn Holstein calves.

Ingestion and absorption of greater quantities of IgG are required to increase serum IgG levels in newborn calves. This could be achieved by adding colostrum replacer (CR) to maternal colostrum (MC). The objective of this study was to investigate whether low and high-quality MC can be enriched with bovine dried CR to achieve adequate serum IgG levels. Male Holstein calves (n = 80; 16/treatment) with birth body weights (BW) of 40 to 52 kg were randomly enrolled to be fed 3.8 L of the following combinations: 30 g/L IgG MC (C1), 60 g/L IgG MC (C2), 90 g/L IgG MC (C3), C1 enriched with 551 g of CR (60 g/L; 30-60CR), or C2 enriched with 620 g of CR (90 g/L: 60-90CR). A subset of 40 calves (8/treatment) had a jugular catheter placed and were fed colostrum containing acetaminophen at a dose of 150 mg/kg of metabolic body weight, to estimate abomasal emptying rate per hour (kABh). Baseline blood samples were taken (0 h), followed by sequential samples at 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, and 48 h relative to initial colostrum feeding. Results for all measurements are presented in the following order, unless otherwise stated: C1, C2, C3, 30-60CR, and 60-90CR. Serum IgG levels at 24 h were different among calves fed C1, C2, C3, 30-60CR, and 60-90CR: 11.8, 24.3, 35.7, 19.9, and 26.9 mg/mL ± 1.02 (mean ± SEM), respectively. Serum IgG at 24 h increased when enriching C1 to 30-60CR, but not from C2 to 60-90CR. Similarly, apparent efficiency of absorption (AEA) values for calves fed C1, C2, C3, 30-60CR, and 60-90CR were different: 42.4, 45.1, 43.2, 36.3, and 33.4% ± 1.93, respectively. Enriching C2 to 60-90CR reduced AEA, and enriching C1 to 30-60CR tended to decrease AEA. The kABh values for C1, C2, C3, 30-60CR, and 60-90CR were also different: 0.16, 0.13, 0.11, 0.09, and 0.09 ± 0.005, respectively. Enriching C1 to 30-60CR or C2 to 60-90CR reduced kABh. However, 30-60CR and 60-90CR have similar kABh compared with a reference colostrum meal (90 g/L IgG, C3). Even though kABh was reduced for 30-60CR, results indicate that C1 has the potential to be enriched and achieve acceptable serum IgG levels at 24 h without affecting AEA.

A soy-yoghurt-honey product as a therapeutic functional food: mode of action and narrative review.

Meal replacements and food supplements are now popular commercial weight loss and nutrition products. This review describes the efficacy, effectiveness, and therapeutic use of one such product - a soy-yoghurt-honey food formulation. The original formula of this product was created more than thirty years ago and since that time it has become well established as a food supplement supporting a healthy lifestyle. Therapeutic evidence for this product is based on numerous scientific studies and clinical trials, focusing particularly on weight management and associated metabolic risk factors and published as peer-reviewed articles. Given the availability of the product and the extent to which it has been experimentally evaluated, it is timely and important that the research is brought together under a single review to consolidate the understanding for the scientific and clinical communities. This review discusses the ingredients and the broad mechanisms of action, which are probably due to the biological properties of the three base components - soy, milk, and honey. It further summarizes and discusses the laboratory and clinical intervention studies, including the biochemical and metabolic mechanisms regarding the insulin- and lipid-lowering, anti-hypertensive, anti-inflammatory, antioxidant, and anti-microbial properties of the overall food and its base products.

Spray drying: Inhalable powders for pulmonary gene therapy.

Gene therapy holds potential in the treatment of many lung pathologies, as indicated by the growing number of clinical trials in recent decades. Pulmonary delivery of gene therapies via inhalation enables localised treatment while the extensive lung surface area promotes enhanced drug absorption. However, loss of nucleic acid integrity during the aerosolisation process, pulmonary clearance, and undesirable drug deposition, pose a major challenge for local delivery. Therefore, the development of nucleic acids into a stable inhalable pharmaceutical preparation would be advantageous. Dry powder inhalers (DPIs) are considered superior compared to nebulisation and pressurised-metered dose inhalers (pMDIs) due to the production of a stable dry formulation, an easy dispensing process, and minimal physical stress. DPIs are commonly produced via spray drying with a range of excipients, solvents, and separation options which can be modified to improve the stability of the nucleic acid cargo. This review details the ideal characteristics for pulmonary delivery and formulation of DPIs for gene therapy to the lungs. The utilisation of spray drying for the production of nucleic acid-containing DPIs is evaluated, with a specific focus on the influence of instrument parameters, the nucleic acid delivery system, and excipients with respect to cargo stability and functionality.

Design of a novel electrospun PVA platform for gene therapy applications using the CHAT peptide.

The electrospinning of polymers has previously shown excellent potential for localised gene therapy. Thus, it was proposed that for the first time, the cell-penetrating CHAT peptide could be utilised to deliver DNA via electrospun nanofibres for localised gene therapy treatment. CHAT is an effective delivery system that encapsulates pDNA to form nanoparticles with the physicochemical characteristics for cellular uptake and protein generation. In this study, the production of smooth, bead-free PVA nanofibres by electrospinning was optimised through a Design of Experiments approach. Bead-free PVA nanofibres were consistently produced using the optimised parameters as follows: applied voltage (8 kV); collector-emitter distance (8 cm); polymer flow rate (4 µL/min); polymer concentration (9 wt% polymer); PVA MW (146-180 kDa). PVA nanofibres were subsequently crosslinked in 1 vol% glutaraldehyde in methanol to confer stability under aqueous conditions with minimal change to morphology, and no compromise to biocompatibility. Nanoparticles of CHAT/pDNA were synthesised and incorporated into the crosslinked nanofibres via soak-loading. Evaluation studies indicated that 100% of the loaded cargo was released within 48 h from the nanofibres. Furthermore, the released pDNA retained structural integrity and functionality as confirmed by gel electrophoresis and transfection studies in NCTC-929 fibroblast cells. Taken together, this data demonstrates that delivery of CHAT/pDNA nanoparticles from electrospun PVA nanofibres represents a solution for localised gene therapy.

Injected human umbilical cord-derived mesenchymal stromal cells do not appear to elicit an inflammatory response in a murine model of osteoarthritis.

OBJECTIVE: This study investigated the effect of hUC-MSCs on osteoarthritis (OA) progression in a xenogeneic model. DESIGN: Male, 10 week-old C57BL/6 mice underwent sham surgery (n = 15) or partial medial meniscectomy (PMM; n = 76). 5x105 hUC-MSCs (from 3 donors: D1, D2 and D3) were phenotyped via RT-qPCR and immunoprofiling their response to inflammatory stimuli.They were injected into the mouse joints 3 and 6 weeks post-surgery, harvesting joints at 8 and 12 weeks post-surgery, respectively. A no cell 'control' group was also used (n = 29). All knee joints were assessed via micro-computed tomography (µCT) and histology and 10 plasma markers were analysed at 12 weeks. RESULTS: PMM resulted in cartilage loss and osteophyte formation resembling human OA at both time-points. Injection of one donor's hUC-MSCs into the joint significantly reduced the loss of joint space at 12 weeks post-operatively compared with the PMM control.This 'effective' population of MSCs up-regulated the genes, IDO and TSG6, when stimulated with inflammatory cytokines, more than those from the other two donors.No evidence of an inflammatory response to the injected cells in any animals, either histologically or with plasma biomarkers, arose. CONCLUSION: Beneficial change in a PMM joint was seen with only one hUC-MSC population, perhaps indicating that cell therapy is not appropriate for severely osteoarthritic joints. However, none of the implanted cells appeared to elicit an inflammatory response at the time-points studied. The variability of UC donors suggests some populations may be more therapeutic than others and donor characterisation is essential in developing allogeneic cell therapies.

Pore-forming bioinks to enable spatio-temporally defined gene delivery in bioprinted tissues.

The regeneration of complex tissues and organs remains a major clinical challenge. With a view towards bioprinting such tissues, we developed a new class of pore-forming bioink to spatially and temporally control the presentation of therapeutic genes within bioprinted tissues. By blending sacrificial and stable hydrogels, we were able to produce bioinks whose porosity increased with time following printing. When combined with amphipathic peptide-based plasmid DNA delivery, these bioinks supported enhanced non-viral gene transfer to stem cells in vitro. By modulating the porosity of these bioinks, it was possible to direct either rapid and transient (pore-forming bioinks), or slower and more sustained (solid bioinks) transfection of host or transplanted cells in vivo. To demonstrate the utility of these bioinks for the bioprinting of spatially complex tissues, they were next used to zonally position stem cells and plasmids encoding for either osteogenic (BMP2) or chondrogenic (combination of TGF-ß3, BMP2 and SOX9) genes within networks of 3D printed thermoplastic fibers to produce mechanically reinforced, gene activated constructs. In vivo, these bioprinted tissues supported the development of a vascularised, bony tissue overlaid by a layer of stable cartilage. When combined with multiple-tool biofabrication strategies, these gene activated bioinks can enable the bioprinting of a wide range of spatially complex tissues.

Influence of alginate backbone on efficacy of thermo-responsive alginate-g-P(NIPAAm) hydrogel as a vehicle for sustained and controlled gene delivery.

Alginate grafted poly(N-isopropylacrylamide) hydrogels (Alg-g-P(NIPAAm)) form three-dimensional networks in mild conditions, making them suitable for incorporation of labile macromolecules, such as DNA. The impact of P(NIPAAm) on copolymer characteristics has been well studied, however the impact of alginate backbone characteristics on copolymer properties has to-date not been investigated. Six different Alg-g-P(NIPAAm) hydrogels were synthesised with 10% alginate, which varied in terms of molecular weight (MW) and mannuronate/guluronate (M/G) monomer ratio, and with 90% NIPAAm in order to develop an injectable and thermo-responsive hydrogel formulation for localised gene delivery. Hydrogel stiffness was directly proportional to MW and the M/G ratio of the alginate backbone. Hydrogels with a high MW or low M/G ratio alginate backbone demonstrated a greater stiffness than those hydrogels comprising low MW alginates and high M/G ratio. Hydrogels with a high M/G ratio also produced a complexed and meshed hydrogel network while hydrogels with a low M/G ratio produced a simplified structure with the superposition of Alg-g-P(NIPAAm) sheets. This study was designed to produce the optimal Alg-g-P(NIPAAm) hydrogel with respect to localised delivery of DNA nanoparticles as a potential medical device for those with castrate resistant prostate cancer (CRPC). Given that CRPC typically disseminates to bone causing pain, morbidity and a plethora of skeletal related events, a copolymer based hydrogel was designed to for long term release of therapeutic DNA nanoparticles. The nanoparticles were comprised of plasmid DNA (pDNA), complexed with an amphipathic cell penetrating peptide termed RALA that is designed to enter cells with high efficiency. Alginate MW and M/G ratio affected stiffness, structure, injectability and degradation of the Alg-g-P(NIPAAm) hydrogel. Algogel 3001, had the optimal characteristics for long-term application and was loaded with RALA/pDNA NPs. From the release profiles, it was evident that RALA protected the pDNA from degradation over a 30-day period and conferred a sustained and controlled release profile from the hydrogels compared to pDNA only. Taken together, we have designed a slowly degrading hydrogel suitable for sustained delivery of nucleic acids when incorporated with the RALA delivery peptide. This now opens up several opportunities for the delivery of therapeutic pDNA from this thermo-responsive hydrogel with numerous medical applications.

Hospital Resource Utilisation by Patients with Community-Acquired Pneumonia.

Little data is available on the resource utilisation of patients admitted with Community-Acquired Pneumonia (CAP) in Ireland. A retrospective review of 50 randomly-selected patients admitted to Beaumont Hospital with CAP was undertaken. The mean length of stay of patients with CAP was 12 days (+/- 16 days). All patients were emergency admissions, all had a chest x-ray, a C-reactive protein blood test, and occupied a public bed at some point during admission. Common antimicrobial therapies were intravenous (IV) amoxicillin/clavulanic acid and oral clarithromycin; 60% received physiotherapy. The estimated mean cost of CAP per patient was €14,802.17. Costs arising from admission to hospital with CAP are substantial, but efforts can be undertaken to ensure that resources are used efficiently to improve patient care such as discharge planning and fewer in-hospital ward transfers.

Mesenchymal stem cell fate following non-viral gene transfection strongly depends on the choice of delivery vector.

Controlling the phenotype of mesenchymal stem cells (MSCs) through the delivery of regulatory genes is a promising strategy in tissue engineering (TE). Essential to effective gene delivery is the choice of gene carrier. Non-viral delivery vectors have been extensively used in TE, however their intrinsic effects on MSC differentiation remain poorly understood. The objective of this study was to investigate the influence of three different classes of non-viral gene delivery vectors: (1) cationic polymers (polyethylenimine, PEI), (2) inorganic nanoparticles (nanohydroxyapatite, nHA) and (3) amphipathic peptides (RALA peptide) on modulating stem cell fate after reporter and therapeutic gene delivery. Despite facilitating similar reporter gene transfection efficiencies, these nanoparticle-based vectors had dramatically different effects on MSC viability, cytoskeletal morphology and differentiation. After reporter gene delivery (pGFP or pLUC), the nHA and RALA vectors supported an elongated MSC morphology, actin stress fibre formation and the development of mature focal adhesions, while cells appeared rounded and less tense following PEI transfection. These changes in MSC morphology correlated with enhanced osteogenesis following nHA and RALA transfection and adipogenesis following PEI transfection. When therapeutic genes encoding for transforming growth factor beta 3 (TGF-ß3) and/or bone morphogenic protein 2 (BMP2) were delivered to MSCs, nHA promoted osteogenesis in 2D culture and the development of an endochondral phenotype in 3D culture, while RALA was less osteogenic and appeared to promote a more stable hyaline cartilage-like phenotype. In contrast, PEI failed to induce robust osteogenesis or chondrogenesis of MSCs, despite effective therapeutic protein production. Taken together, these results demonstrate that the differentiation of MSCs through the application of non-viral gene delivery strategies depends not only on the gene delivered, but also on the gene carrier itself. STATEMENT OF SIGNIFICANCE: Nanoparticle-based non-viral gene delivery vectors have been extensively used in regenerative medicine, however their intrinsic effects on mesenchymal stem cell (MSC) differentiation remain poorly understood. This paper demonstrates that different classes of commonly used non-viral vectors are not inert and they have a strong effect on cell morphology, stress fiber formation and gene transcription in MSCs, which in turn modulates their capacity to differentiate towards osteogenic, adipogenic and chondrogenic lineages. These results also point to the need for careful and tissue-specific selection of nanoparticle-based delivery vectors to prevent undesired phenotypic changes and off-target effects when delivering therapeutic genes to damaged or diseased tissues.

Critical review: Injectability of calcium phosphate pastes and cements.

Calcium phosphate cements (CPC) have seen clinical success in many dental and orthopaedic applications in recent years. The properties of CPC essential for clinical success are reviewed in this article, which includes properties of the set cement (e.g. bioresorbability, biocompatibility, porosity and mechanical properties) and unset cement (e.g. setting time, cohesion, flow properties and ease of delivery to the surgical site). Emphasis is on the delivery of calcium phosphate (CaP) pastes and CPC, in particular the occurrence of separation of the liquid and solid components of the pastes and cements during injection; and established methods to reduce this phase separation. In addition a review of phase separation mechanisms observed during the extrusion of other biphasic paste systems and the theoretical models used to describe these mechanisms are discussed. STATEMENT OF SIGNIFICANCE: Occurrence of phase separation of calcium phosphate pastes and cements during injection limits their full exploitation as a bone substitute in minimally invasive surgical applications. Due to lack of theoretical understanding of the phase separation mechanism(s), optimisation of an injectable CPC that satisfies clinical requirements has proven difficult. However, phase separation of pastes during delivery has been the focus across several research fields. Therefore in addition to a review of methods to reduce phase separation of CPC and the associated constraints, a review of phase separation mechanisms observed during extrusion of other pastes and the theoretical models used to describe these mechanisms is presented. It is anticipated this review will benefit future attempts to develop injectable calcium phosphate based systems.

A Rare Case of an Early Postoperative Obstructive Ileus in a Young Female Patient due to a Residual Trichobezoar Mass.

Trichobezoar is a rare cause of small bowel obstruction, whereby a mass forms most commonly in the stomach and duodenum of young females, from ingestion of hair, a condition known as trichophagia. We present a case of recurrent small bowel obstruction due to a residual hair mass that was removed surgically in a young female patient who had a laparotomy and gastrotomy for removal of a large gastric trichobezoar just two weeks prior to the current admission. This case illustrates the importance of a thorough inspection of the whole bowel to ensure that no residual bezoars remain after surgery.

Longitudinal copy number, whole exome and targeted deep sequencing of 'good risk' IGHV-mutated CLL patients with progressive disease.

The biological features of IGHV-M chronic lymphocytic leukemia responsible for disease progression are still poorly understood. We undertook a longitudinal study close to diagnosis, pre-treatment and post relapse in 13 patients presenting with cMBL or Stage A disease and good-risk biomarkers (IGHV-M genes, no del(17p) or del(11q) and low CD38 expression) who nevertheless developed progressive disease, of whom 10 have required therapy. Using cytogenetics, fluorescence in situ hybridisation, genome-wide DNA methylation and copy number analysis together with whole exome, targeted deep- and Sanger sequencing at diagnosis, we identified mutations in established chronic lymphocytic leukemia driver genes in nine patients (69%), non-coding mutations (PAX5 enhancer region) in three patients and genomic complexity in two patients. Branching evolutionary trajectories predominated (n=9/13), revealing intra-tumoural epi- and genetic heterogeneity and sub-clonal competition before therapy. Of the patients subsequently requiring treatment, two had sub-clonal TP53 mutations that would not be detected by standard methodologies, three qualified for the very-low-risk category defined by integrated mutational and cytogenetic analysis and yet had established or putative driver mutations and one patient developed progressive, therapy-refractory disease associated with the emergence of an IGHV-U clone. These data suggest that extended genomic and immunogenetic screening may have clinical utility in patients with apparent good-risk disease.

Normative data for three tests of visuocognitive function in primary school children: cross-sectional study.

BACKGROUND/AIMS: There is an increasing recognition that visuocognitive difficulties occur in children with neurodevelopmental problems. We obtained normative data for the performance of primary school children using three tests of visuocognitive function that are practicable in a clinical setting. METHODS: We tested 214 children aged between 4 and 11 years without known developmental problems, using tests to assess (1) orientation recognition and adaptive movement (postbox task), (2) object recognition (rectangles task) and (3) spatial integration (contours task). RESULTS: 96% could do the postbox task with ease-only 4% (all aged <9 years) exhibited minor difficulties. Errors in the rectangles task decreased with age: 33% of children aged 4-5 years had major difficulties but >99% of children aged ≥6 years had no, or minor, difficulties. Median scores for the contours task improved with age, and after age 8 years, 99% could see the contour using long-range spatial integration rather than density. CONCLUSIONS: These different aspects of children's visuocognitive performance were testable in a field setting. The data provide a benchmark by which to judge performance of children with neurodevelopmental problems and may be useful in assessment with a view to providing effective supportive strategies for children whose visuocognitive skills are lower than the expectation for their age.

Measuring growth and obesity across childhood and adolescence.

The dramatic rise in childhood obesity has driven the demand for tools better able to assess and define obesity and risk for related co-morbidities. In addition, the early life origins of non-communicable diseases including type 2 diabetes are associated with subtle alterations in growth and body composition, including total and regional body fatness, limb/trunk length and skeletal muscle mass (SMM). Consequently improved tools based on national reference data, which capture these body components must be developed as the limitations of BMI as a measure of overweight and obesity and associated cardiometabolic risk are now recognised. Furthermore, waist circumference as a measure of abdominal fatness in children is now endorsed by the International Diabetes Federation and National Institute for Clinical and Health Excellence for diagnostic and monitoring purposes. The present paper aims to review the research on growth-related variations in body composition and proportions, together with how national references for percentage body fat, SMM and leg/trunk length have been developed. Where collection of these measures is not possible, alternative proxy measures including thigh and hip circumferences are suggested. Finally, body ratios including the waist:height and muscle:fat ratios are highlighted as potential measures of cardiometabolic disease risk. In conclusion, a collection of national references for individual body measures have been produced against which children and youths can be assessed. Collectively, they have the capacity to build a better picture of an individual's phenotype, which represents their risk for cardiometabolic disease beyond that of the capability of BMI.

Identifying a consistent pattern of neural function in attention deficit hyperactivity disorder: a meta-analysis.

BACKGROUND: The neurobiological underpinnings of attention deficit hyperactivity disorder (ADHD) are inconclusive. Activation abnormalities across brain regions in ADHD compared with healthy controls highlighted in task-based functional magnetic resonance imaging (fMRI) studies are heterogeneous. To identify a consistent pattern of neural dysfunction in ADHD, a meta-analysis of fMRI studies using Go/no-go, Stop and N-back tasks was undertaken. METHOD: Several databases were searched using the key words: 'ADHD and fMRI' and 'ADHD and fMRI task'. In all, 20 studies met inclusion criteria comprising 334 patients with ADHD and 372 healthy controls and were split into N-back, Stop task and Go/no-go case-control groups. Using Signed Differential Mapping each batch was meta-analysed individually and meta-regression analyses were used to examine the effects of exposure to methylphenidate (MPH), length of MPH wash-out period, ADHD subtype, age and intelligence quotient (IQ) differences upon neural dysfunction in ADHD. RESULTS: Across all tasks less activity in frontal lobe regions compared with controls was detected. Less exposure to treatment and lengthier wash-out times resulted in less left medial frontal cortex activation in N-back and Go/no-go studies. Higher percentage of combined-type ADHD resulted in less superior and inferior frontal gyrus activation. Different IQ scores between groups were linked to reduced right caudate activity in ADHD. CONCLUSIONS: Consistent frontal deficits imply homogeneous cognitive strategies involved in ADHD behavioural control. Our findings suggest a link between fMRI results and the potentially normalizing effect of treatment and signify a need for segregated examination and contrast of differences in sample characteristics in future studies.

Skeletal muscle mass reference curves for children and adolescents.

BACKGROUND: Skeletal muscle is key to motor development and represents a major metabolic end organ that aids glycaemic regulation. OBJECTIVES: To create gender-specific reference curves for fat-free mass (FFM) and appendicular (limb) skeletal muscle mass (SMMa) in children and adolescents. To examine the muscle-to-fat ratio in relation to body mass index (BMI) for age and gender. METHODS: Body composition was measured by segmental bioelectrical impedance (BIA, Tanita BC418) in 1985 Caucasian children aged 5-18.8 years. Skeletal muscle mass data from the four limbs were used to derive smoothed centile curves and the muscle-to-fat ratio. RESULTS: The centile curves illustrate the developmental patterns of %FFM and SMMa. While the %FFM curves differ markedly between boys and girls, the SMMa (kg), %SMMa and %SMMa/FFM show some similarities in shape and variance, together with some gender-specific characteristics. Existing BMI curves do not reveal these gender differences. Muscle-to-fat ratio showed a very wide range with means differing between boys and girls and across fifths of BMI z-score. CONCLUSIONS: BIA assessment of %FFM and SMMa represents a significant advance in nutritional assessment since these body composition components are associated with metabolic health. Muscle-to-fat ratio has the potential to provide a better index of future metabolic health.

Children's body fatness and prevalence of obesity in relation to height for age.

BACKGROUND: Children who are taller for their age tend to have higher BMI and, as a group, a greater prevalence of overweight/obesity. AIM: To examine the relationship between height for age with three measures of adiposity. SUBJECTS AND METHODS: Height, weight, BMI, % body fat (%BF) (by bioimpedance) and waist circumference (WC) were measured in 2298 Caucasian children (1251 boys) aged 4-14 years. Standard deviation scores (SDS) were derived and cases divided into quartiles of height SDS. Mean BMI, %BF and WC SDSs were compared across quartiles. Prevalence of overweight/obesity, over-fat/obesity and abdominal overweight/obesity within each height for age quartile was determined. RESULTS: Mean BMI, %BF and WC SDSs increased with increasing quartile of height SDS. Overweight/obesity, overfat/obesity and abdominal overweight/obesity prevalence increased from the first quartile (8.8-13%) to the fourth quartile (32.7-45.5%) of height SDS. A significant rising trend in mean SDSs for BMI, %BF and WC was also observed with increasing height SDS in overweight/obese children only. CONCLUSION: A higher prevalence of excess weight, measured by BMI SDS among children taller for their age, is replicated when using %BF and WC. Height for age measurement has potential in screening children for later risk of obesity.