Long-term association between dairy consumption and risk of childhood obesity: a systematic review and meta-analysis of prospective cohort studies

BACKGROUND/OBJECTIVES

Data from small-scale, short-term, clinical trials suggest a beneficial effect of dairy consumption on the risk of childhood obesity; however, the long-term association is unclear. Therefore, we aim to examine the longitudinal association between dairy consumption and the risk of overweight/obesity in children and adolescents by conducting a systematic review and meta-analysis of prospective cohort studies.

SUBJECTS/METHODS

Eligible studies were identified by searching PubMed and EMBASE through March 2015. Additional studies were retrieved via Google Scholar or a hand review of the reference lists from relevant articles. Pooled associations of interest were estimated by using a random-effects model. The heterogeneity for each pooled analysis was evaluated by I(2) statistic as well as by Cochran's Q test. Publication bias was assessed by using both Egger's and Begg's tests.

RESULTS

Ten studies comprising 46,011 children and adolescents with an average 3-year follow-up were included. As compared with those who were in the lowest group of dairy consumption, children in the highest intake group were 38% less likely to have childhood overweight/obesity (pooled odds ratio (OR)=0.62; 95% confidence interval (CI): 0.49, 0.80). With each 1 serving/day increment in dairy consumption, the percentage of body fat was reduced by 0.65% (β=0.65; 95% CI: -1.35, 0.06; P=0.07), and the risk of overweight/obesity was 13% lower (OR=0.87; 95% CI: 0.74, 0.98).

CONCLUSIONS

Accumulated evidence from prospective cohort studies suggests that dairy consumption is inversely and longitudinally associated with the risk of childhood overweight/obesity. Further studies are warranted to examine the types of dairy products in relation to the risk of childhood overweight/obesity.

Spectral properties and highly efficient continuous-wave laser operation in Nd-doped Sr(1-x)Y(x)F(2+x) crystals

Spectral properties of Nd:Sr(1-x)Y(x)F(2+x) crystals were investigated. Compared with Nd:SrF2, the spectral parameters of Nd:Sr(1-x)Y(x)F(2+x) (x=0.05,0.1) were altered in a large scale. LD-pumped true CW laser has been demonstrated in the crystals. The slope efficiency up to 43.5% in 0.43% Nd:Sr0.95Y0.05F2.05 was achieved. The system is a promising candidate for highly efficient lasers.

Effect of exercise combined with dietary intervention on obese children and adolescents associated with the FTO rs9939609 polymorphism

OBJECTIVE

Aim of this study was to investigate the association of the FTO rs9939609 polymorphism with the effects of the exercise and dietary intervention on obese adolescents and children in China.

PATIENTS AND METHODS

Total 138 chinese children and adolescents (77 males and 61 females, aged 10-18 years) were recruited in the 2012 summer camp in Shanghai. Dietary and exercise intervention was performed for four weeks. Obesity related parameters were detected by the physical examination before and after four-week's intervention. Genotyping of the FTO rs9939609 was performed by using a TaqMan SNP Genotyping Assay. SPSS 19.0 were used to do the statistical analysis.

RESULTS

Finally, 135 campers were investigated in this study. The AA, AT and TT genotype frequencies of rs9939609 were 5.2%, 33.3% and 61.5%, respectively. The BMI in individuals with the genotype AA (or AT) was significantly higher compared with their with TT genotype (p = 0.044). The levels of body mass index (BMI), insulin (INS), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), red blood cell (RBC), Hemoglobin (HB) and hematocrit (HCT) in campers were significantly declined by the combined intervention (p < 0.05). Moreover, the levels of TC, low-density lipoprotein (LDL), RBC, HB, and HCT in the camper with genotype AA (or AT) were significantly decreased by the combined intervention compared with the camper with genotype TT (p < 0.05).

CONCLUSIONS

The effects of exercise combined with dietary intervention on obesity were associated with the FTO rs9939609 polymorphism in chinese adolescents and children.

Lack of association between the hOGG1 gene Ser326Cys polymorphism and gastric cancer risk: evidence from a case-control study and a meta-analysis

The association between the human 8-oxoguanine glycosylase 1 (hOGG1) gene Ser326Cys polymorphism (rs1052133) and gastric cancer has been widely evaluated, yet a definitive answer to whether this association exists is lacking. We first conducted a case-control study to assess this association in a large Han Chinese population, and then performed a meta-analysis to further address this issue. This case-control study involved 448 patients clinically diagnosed with gastric cancer and 372 cancer-free control individuals from China. Genotyping was conducted using the polymerase chain reaction-ligase detection reaction method. Meta-analysis was performed by the STATA software. Data and study quality were assessed in duplicate. Our case-control association study indicated that there were no significant differences in the genotype and allele distributions of the Ser326Cys polymorphism between gastric cancer patients and controls (P = 0.8026 for genotype, and P = 0.5857 for allele), consistent with the results of the subsequent meta-analysis involving 2745 patients and 4588 controls under both allelic [odds ratio (OR) = 1.02; 95% confidence interval (CI) = 0.91-1.14; P = 0.739] and dominant (OR = 0.97; 95%CI = 0.78-1.21; P = 0.803) models. Further subgroup analyses by ethnicity, source of controls, and sample size also did not detect any positive associations in this meta-analysis. Overall, our study in the Han Chinese population, along with the meta-analysis, failed to confirm the association of the hOGG1 gene Ser326Cys polymorphism with gastric cancer risk, even across different ethnic populations.

Synthesis and molecular characterization of acrylate liquid crystalline resin monomers (ALCRM)

A novel biocompatible resin monomer 4&mdash;3&mdash;(acryloyloxy)&mdash;2&mdash;hydroxypropoxy) phenyl 4&mdash;(3&mdash;(acryloyloxy)&mdash;2&mdash;hydroxypropoxy) benzoate, as an oral restorative &mdash; acrylate liquid crystalline resin monomer (ALCRM) was synthesized. The intermediate product and the final product were characterized by differential scanning calorimetry (DSC), polarized optical microscope (POM), and nuclear magnetic resonance (NMR). A resin matrix which has a potential application in dental composites was prepared by photopolymerizing ALCRM and triethylene glycol dimethacrylate (TEGDMA) as a primary and diluted monomer with a photosensitizer of camphorquinone (CQ) and 2&mdash;(Dimethylamino)ethyl methacrylate (DMAEMA) mixture. The molar ratio of ALCRM and TEGDMA was 7:3. The properties such as the curing depth, curing time, and the volumetric shrinkage of the resin matrix were investigated and compared with a traditional composite resin matrix Bis&mdash;GMA. After photocuring polymerization, the conversion degree of the resin matrix is 68.06%, higher than Bis&mdash;GMA/TEGDMA; the curing time is 4.08±0.20min, the curing depth is 2.10±0.17mm, and the volumetric shrinkage is 3.62%±0.26%. All the properties exhibit a better performance of the prepared resin matrix than Bis&mdash;GMA.

Relationship between serum levels of endogenous secretory RAGE and blood pressure in male nondiabetic patients with obstructive sleep apnea

The interaction of advanced glycation end products (AGE) and their specific cell-surface receptor (RAGE) has an important role in the pathogenesis of cardiovascular disease and diabetic complications. Two isoforms of C-truncated RAGE, soluble RAGE (sRAGE) and endogenous secretory RAGE (esRAGE), may prevent activation of RAGE signaling by acting as decoys. This study investigated whether serum esRAGE and sRAGE levels are associated with blood pressure in nondiabetic patients with obstructive sleep apnea (OSA). Male nondiabetic patients (n=139) with OSA were enrolled. Serum esRAGE and sRAGE levels were examined using enzyme-linked immunosorbent assay. Three consecutive seated systolic blood pressure (SBP) and diastolic blood pressure (DBP) measurements were obtained at 5-min intervals in the morning. In univariate analysis, there was a significant correlation between serum esRAGE and SBP or DBP, but not between serum sRAGE and SBP or DBP. Multiple regression analysis showed that SBP was independently associated with waist circumference, HbA1c, minimum SaO2 and serum esRAGE, and that DBP was independently associated with low-density lipoprotein cholesterol, apnea-hypopnea index, serum AGE and body mass index, but not with serum esRAGE. These results indicated that serum esRAGE levels were inversely associated with blood pressure, especially SBP, in male nondiabetic patients with OSA. esRAGE may have a protective role against hypertension in patients with OSA, and it may be a novel biomarker for OSA patients at high risk of developing cardiovascular diseases.

3D fluoroscopic image estimation using patient-specific 4DCBCT-based motion models

3D fluoroscopic images represent volumetric patient anatomy during treatment with high spatial and temporal resolution. 3D fluoroscopic images estimated using motion models built using 4DCT images, taken days or weeks prior to treatment, do not reliably represent patient anatomy during treatment. In this study we developed and performed initial evaluation of techniques to develop patient-specific motion models from 4D cone-beam CT (4DCBCT) images, taken immediately before treatment, and used these models to estimate 3D fluoroscopic images based on 2D kV projections captured during treatment. We evaluate the accuracy of 3D fluoroscopic images by comparison to ground truth digital and physical phantom images. The performance of 4DCBCT-based and 4DCT-based motion models are compared in simulated clinical situations representing tumor baseline shift or initial patient positioning errors. The results of this study demonstrate the ability for 4DCBCT imaging to generate motion models that can account for changes that cannot be accounted for with 4DCT-based motion models. When simulating tumor baseline shift and patient positioning errors of up to 5 mm, the average tumor localization error and the 95th percentile error in six datasets were 1.20 and 2.2 mm, respectively, for 4DCBCT-based motion models. 4DCT-based motion models applied to the same six datasets resulted in average tumor localization error and the 95th percentile error of 4.18 and 5.4 mm, respectively. Analysis of voxel-wise intensity differences was also conducted for all experiments. In summary, this study demonstrates the feasibility of 4DCBCT-based 3D fluoroscopic image generation in digital and physical phantoms and shows the potential advantage of 4DCBCT-based 3D fluoroscopic image estimation when there are changes in anatomy between the time of 4DCT imaging and the time of treatment delivery.

A microfluidic device enabling high-efficiency single cell trapping

Single cell trapping increasingly serves as a key manipulation technique in single cell analysis for many cutting-edge cell studies. Due to their inherent advantages, microfluidic devices have been widely used to enable single cell immobilization. To further improve the single cell trapping efficiency, this paper reports on a passive hydrodynamic microfluidic device based on the "least flow resistance path" principle with geometry optimized in line with corresponding cell types. Different from serpentine structure, the core trapping structure of the micro-device consists of a series of concatenated T and inverse T junction pairs which function as bypassing channels and trapping constrictions. This new device enhances the single cell trapping efficiency from three aspects: (1) there is no need to deploy very long or complicated channels to adjust flow resistance, thus saving space for each trapping unit; (2) the trapping works in a "deterministic" manner, thus saving a great deal of cell samples; and (3) the compact configuration allows shorter flowing path of cells in multiple channels, thus increasing the speed and throughput of cell trapping. The mathematical model of the design was proposed and optimization of associated key geometric parameters was conducted based on computational fluid dynamics (CFD) simulation. As a proof demonstration, two types of PDMS microfluidic devices were fabricated to trap HeLa and HEK-293T cells with relatively significant differences in cell sizes. Experimental results showed 100% cell trapping and 90% single cell trapping over 4 × 100 trap sites for these two cell types, respectively. The space saving is estimated to be 2-fold and the cell trapping speed enhancement to be 3-fold compared to previously reported devices. This device can be used for trapping various types of cells and expanded to trap cells in the order of tens of thousands on 1-cm(2) scale area, as a promising tool to pattern large-scale single cells on specific substrates and facilitate on-chip cellular assay at the single cell level.

Separation of cyclotron-produced 44Sc from a natural calcium target using a dipentyl pentylphosphonate functionalized extraction resin

Significant interest in ⁴⁴Sc as a radioactive synthon to label small molecules for positron emission tomography (PET) imaging has been recently observed. Despite the efforts of several research groups, the ideal ⁴⁴Sc production and separation method remains elusive. Herein, we propose a novel separation method to obtain ⁴⁴Sc from the proton irradiation of calcium targets based on extraction chromatography, which promises to greatly simplify current production methodologies. Using the commercially available Uranium and Tetravalent Actinides (UTEVA) extraction resin we were able to rapidly (<20min) recover >80% of the activity generated at end of bombardment (EoB) in small ~1M HCl fractions (400μL). The chemical purity of the ⁴⁴Sc eluates was evaluated through chelation with DOTA and DTPA, and by trace metal analysis using microwave induced plasma atomic emission spectrometry. The distribution coefficients (K_d) of Sc(III) and Ca(II) in UTEVA were determined in HCl medium in a range of concentrations from zero to 12.1M. The ⁴⁴Sc obtained with our method proved to be suitable for the direct labeling of small biomolecules for PET imaging, with excellent specific activities and radiochemical purity.