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Background: Child eating behaviors (CEBs) and parental feeding practices (PFPs) play critical roles in childhood obesity. However, the bidirectional relationships between CEBs and PFPs remain equivocal. This longitudinal study aimed to explore their bidirectional relationships. Methods: A convenience sample of 870 parents with preschoolers was recruited in this longitudinal study (Shanghai, China). Three non-responsive feeding practices (NFPs), three responsive feeding practices (RFPs), five CEBs, and covariates were collected using validated questionnaires at baseline and the 6-month follow-up. Cross-lagged analyses using structural equation modeling (SEM) were performed to examine their bidirectional relationships. Results: Eight hundred and fifty-three parents completed questionnaires, with a response rate of 98%. The mean age of their children at baseline was 4.39 years (standard deviation = 0.72 years). Eighteen out of sixty longitudinal cross-lagged paths were statistically significant. Parental encouragement of healthy eating and content-restricted feeding were found to be bidirectionally associated with child food fussiness. Four parent-driven associations and one child-driven association were identified between RFPs and CEBs. For example, monitoring was negatively associated with children's unhealthy eating habits (β = −0.066, standard error (SE) = 0.025, p < 0.01). Eight child-driven associations and one parent-driven association were observed between NFPs and CEBs. For example, higher child satiety responsiveness predicted a higher pressure to eat (β = 0.057, SE = 0.029, p < 0.01) and the use of food as a reward (β = 0.083, SE = 0.031, p < 0.01). Conclusions: There were bidirectional, parent-driven, and child-driven associations. Parents should be encouraged to adopt RFPs to shape CEBs. Increasing parents' understanding of CEBs and providing them with reasonable coping strategies would help optimize PFPs. [ABSTRACT FROM AUTHOR]

Alkaline phosphatase (ALP) activity and pyrophosphate ion (PPi) levels are remarkable for the human body functions such as signal transduction pathways and metabolism. Current quantitative methods mainly focus on developing complicated organic substrates or employing unstable metal ions as signal-regulated medium. Herein, we have developed a facile hydrothermal method for preparing FeWO4 nanomaterials with intrinsic peroxidase-like activity and further confirmed that such a catalytic activity could be significantly enhanced by adjusting the size and oxygen vacancy content. More encouragingly, PPi can easily inhibit the catalytic activity of FeWO4, whereas orthophosphate ions (Pi) cannot. Therefore, we constructed an FeWO4-based colorimetric assay for sensing PPi by means of the classical 3,3′,5,5′-tetramethylbenzidine-peroxidase chromogenic reaction. A facile and reliable ALP activity assay was also designed and developed because of the logical regulation of the peroxidase-like activity of FeWO4 through the ALP-catalyzed hydrolysis of PPi into Pi. Based on the clear mechanism and mimetic-enzyme FeWO4-catalyzed amplification, the sensing system exhibited excellent performance and was able to evaluate ALP activity in real serum samples and screen for potential ALP inhibitors. The proposed mimetic enzyme-involved colorimetric assay provides an alternative pathway, and FeWO4 nanomaterials with excellent performance have great potential for further biosensing and biomedical applications. [ABSTRACT FROM AUTHOR]

Glucose homeostasis is controlled by insulin in part through the stimulation of glucose transport in muscle and fat cells. This insulin signaling pathway requires phosphatidylinositol (PI) 3-kinase-mediated 3′-polyphos-phoinositide generation and activation of Akt/protein kinase B. Previous experiments using dominant negative constructs and gene ablation in mice suggested that two phosphoinositide phosphatases, SH2 domain-containing inositol 5′-phosphatase 2 (SHIP2) and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) negatively regulate this insulin signaling pathway. Here we directly tested this hypothesis by selectively inhibiting the expression of SHIP2 or PTEN in intact cultured 3T3-L1 adipocytes through the use of short interfering RNA (siRNA). Attenuation of PTEN expression by RNAi markedly enhanced insulin-stimulated Akt and glycogen synthase kinase 3α (GSK-3α) phosphorylation, as well as deoxyglucose transport in 3T3-L1 adipocytes. In contrast, depletion of SHIP2 protein by about 90% surprisingly failed to modulate these insulin-regulated events under identical assay conditions. In control studies, no diminution of insulin signaling to the mitogen-activated protein kinases Erk1 and Erk2 was observed when either PTEN or SHIP2 were depleted. Taken together, these results demonstrate that endogenous PTEN functions as a suppressor of insulin signaling to glucose transport through the PI 3-kinase pathway in cultured 3T3-L1 adipocytes. [ABSTRACT FROM AUTHOR]

Abstract: Aflatoxin B1 (AFB1) is a severe threat to human and animal health. The aflatoxin B1 aldehyde reductase (AFAR) family specifically catalyzes AFB1-dialdehyde, a toxic metabolic intermediate of AFB1, producing a nontoxic dialcohol. Although several AFARs have been found and characterized, the binding specificity of the family for AFB1-dialdehyde remains unclear. Herein, according to the published sequence, we cloned a porcine AFAR gene. Recombinant porcine AFAR was expressed and purified from Escherichia coli as hexa-histidine tagged fusion protein. Using the cloned porcine AFAR as a model, site-directed mutagenesis combined with high performance liquid chromatography studies revealed that the substitution of Trp266 with Ala resulted in almost complete loss of catalytic activity for AFB1-dialdehyde. Interestingly, the substitution of Met86 with Ala exhibited an obviously increased activity to the dialdehyde. Based on these results and by using molecular docking simulations, this work provides a structural explanation for why the AFAR family exhibits high specificity for AFB1-dialdehyde. The Trp266 residue in porcine AFAR plays a critical role in stabilizing the binding of AFB1-dialdehyde in the active pocket through the hydrophobic interaction of the side-chain indole ring of Trp266 with the fused coumarin rings of the dialdehyde molecule. The enhanced activity of M86A may be attributed to the formed π–π stacking interaction between Trp266 and the dialdehyde. In addition, other hydrophobic residues (e.g. Phe and Trp) around the dialdehyde molecule also stabilize the substrate binding. The findings may contribute to understanding the substrate specificity of the AFAR family for AFB1-dialdehyde. [Copyright &y& Elsevier]