27 research outputs found
Specific Alleles of Bitter Receptor Genes Influence Human Sensitivity to the Bitterness of Aloin and Saccharin
SummaryVariation in human taste is a well-known phenomenon [1]. However, little is known about the molecular basis for it. Bitter taste in humans is believed to be mediated by a family of 25 G protein-coupled receptors (hT2Rs, or TAS2Rs) [2–7]. Despite recent progress in the functional expression of hT2Rs in vitro, up until now, hT2R38, a receptor for phenylthiocarbamide (PTC), was the only gene directly linked to variations in human bitter taste [8]. Here we report that polymorphism in two hT2R genes results in different receptor activities and different taste sensitivities to three bitter molecules. The hT2R43 gene allele, which encodes a protein with tryptophan in position 35, makes people very sensitive to the bitterness of the natural plant compounds aloin and aristolochic acid. People who do not possess this allele do not taste these compounds at low concentrations. The same hT2R43 gene allele makes people more sensitive to the bitterness of an artificial sweetener, saccharin. In addition, a closely related gene's (hT2R44's) allele also makes people more sensitive to the bitterness of saccharin. We also demonstrated that some people do not possess certain hT2R genes, contributing to taste variation between individuals. Our findings thus reveal new examples of variations in human taste and provide a molecular basis for them
Neural Induction Potential and MRI of ADSCs Labeled Cationic Superparamagnetic Iron Oxide Nanoparticle In Vitro
Magnetic resonance imaging (MRI) combined with contrast agents is believed to be useful for stem cell tracking in vivo, and the aim of this research was to investigate the biosafety and neural induction of SD rat-originated adipose derived stem cells (ADSCs) using cationic superparamagnetic iron oxide (SPIO) nanoparticle which was synthesized by the improved polyol method, in order to allow visualization using in vitro MRI. The scan protocols were performed with T2-mapping sequence; meanwhile, the ultrastructure of labeled cells was observed by transmission electron microscopy (TEM) while the iron content was measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). After neural induction, nestin and NSE (neural markers) were obviously expressed. In vitro MRI showed that the cationic PEG/PEI-modified SPIO nanoparticles could achieve great relaxation performance and favourable longevity. And the ICP-AES quantified the lowest iron content that could be detected by MRI as 1.56~1.8 pg/cell. This study showed that the cationic SPIO could be directly used to label ADSCs, which could then inductively differentiate into nerve and be imaged by in vitro MRI, which would exhibit important guiding significance for the further in vivo MRI towards animal models with neurodegenerative disorders
Stress coping, cognitive flexibility and emotion regulation of preschoolers.
The current study investigated the coping strategies 4-year-old preschoolers used for nine different everyday life stressors. Interview was conducted. Results showed that preschoolers (N=18) reported the highest usage of the primary control-direct problem solving and the secondary control-social/spiritual support. Correlations between gender and the frequency of strategies used were insignificance. Additionally, cognitive flexibility was found to be significantly correlated with secondary-control coping, though emotion regulation did not correlate with any of the coping strategies.Bachelor of Art
Stress coping and the early development of theory of mind and executive function : a study of preschoolers in Singapore.
This study examined the relations between the executive function, theory of mind of 4-and 5-year old Singaporean preschoolers and 3 types of stress coping strategies, problem solving,social support and avoidance. Preschoolers (N = 20) were verbally interviewed about stress and coping. The Flexible Item Selection Task and the real and apparent emotion task was used as an executive function measure and theory of mind measure respectively. Family and social stressors were the major sources of stress and problem solving was used significantly more than social support or avoidance. The development of executive function was linked significantly with problem solving and social support. Theory of mind and preschoolers’ age were negatively correlated with avoidance strategies.Bachelor of Art
Stress coping and the development of executive function : a study on 4-year old preschoolers in Singapore.
The purpose of this study was to examine the relationship between self-reported coping mechanisms and executive function (EF) in 4-year old Singaporean preschoolers. Children (N = 18) were given a battery of EF tests presented in the form of child-friendly games in addition to an interview on challenging events and coping strategies (Frydenberg, 2004).Two measure of EF namely, cognitive flexibility and emotion regulation were hypothesized to be positively related to productive coping mechanisms defined as secondary control coping strategies. Results indicated that cognitive flexibility was positively correlated with productive coping strategies. Conversely, no significant relationship was found between emotion regulation and productive coping strategies. Directions for future research on EF and coping in preschoolers are suggested.Bachelor of Art
Determination of trace Pb(II), Cd(II) and Zn(II) using differential pulse stripping voltammetry without Hg modification
National Natural Scientific Foundation of China [21175112]; Fund of Key Laboratory of Global Change and Marine-Atmospheric Chemistry, SOA [GCMAC 1204]; Fujian Key Projects of Science and Technology [2011YZ0001-1]In this work, we reported a simultaneous determination approach for Pb(II), Cd(II) and Zn(II) at mu g L-1 concentration levels using differential pulse stripping voltammetry on a bismuth film electrode (BiFE). The BiFE could be prepared in situ when the sample solution contained a suitable amount of Bi(NO)(3), and its analytical performance was evaluated for the simultaneous determination of Pb(II), Cd(II) and Zn(II) in solutions. The determination limits were found to be 0.19 mu g L-1 for Zn(II), and 0.28 mu g L-1 for Pb(II) and Cd(II), with a preconcentration time of 300 s. The BiFE approach was successfully applied to determine Pb(II), Cd(II) and Zn(II) in tea leaf and infusion samples, and the results were in agreement with those obtained using an atomic absorption spectrometry approach. Without Hg usage, the in situ preparation for BiFE supplied a green and acceptability sensitive method for the determination of the heavy metal ions
Neutropenia after intravenous immunoglobulin therapy is associated with coronary artery lesions in children with Kawasaki disease: a case control study
Abstract Background To evaluate differences in laboratory parameters, clinical presentation, and incidence of coronary artery lesions (CAL) between children with neutropenic and non-neutropenic Kawasaki disease (KD). Methods All consecutive KD patients that presented to the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University in Wenzhou, China between January 2005 and December 2015 were included in this study. Patients were divided into two groups (KD with neutropenia (NKD) and KD without neutropenia (NNKD)) based on whether or not they developed neutropenia during the course of treatment. We compared differences in clinical manifestations, laboratory parameters, and treatment protocols between groups. We also evaluated the relationship between neutropenia with immunoglobulin dosage and incidence of CAL. Results An IVIG treatment regimen of 2 g/kg*1d was associated with a lower incidence of neutropenia compared to the 1 g/kg*2d protocol. The incidence of CAL was higher in KD patients with neutropenia than in those without. Subgroup analysis showed no difference in the incidence of CAL among the different age groups between KD patients with and without neutropenia. Conclusions Follow up ultrasonic echocardiography should be performed in KD patients with neutropenia in order to allow for early detection of CAL and timely intervention
Fluorescence determination of acrylamide in heat-processed foods
A simple and rapid fluorescence method has been developed for the determination of acrylamide in heat-processed food samples. In the determination, acrylamide is degraded through Hofmann reaction to generate vinyl amine, and pyrrolinone is produced when the vinyl amine reacts with fluorescamine, resulting in a strong fluorescence emission at 480 nm. Hofmann reaction is a key step for the fluorescence determination of acrylaminde, and the reaction conditions are investigated and optimized. Under the optimal conditions, the fluorescence intensity increases with the increase of acrylamide concentrations. The linear range between the fluorescence intensity and the square-root of acrylamide concentrations is from 0.05 μg mL-1 to 20 μg mL-1 with the correlation coefficient R2=0.9935. The detection limit is 0.015 μg mL-1 and the recovery for food samples is from 66.0% to 110.6%. In comparison with Specification of Entry&Exit Inspection and Quarantine Bureau of The Peoples Republic of China (SN/T 2281-2009), the method showed comparable results and demonstrated the accuracy of the method. ? 2014 Elsevier B.V. All rights reserved
2-Dodecyl-6-Methoxycyclohexa-2, 5-Diene-1, 4-Dione isolated from Averrhoa carambola L. root inhibits high glucose-induced EMT in HK-2 cells through targeting the regulation of miR-21–5p/Smad7 signaling pathway
Objective: 2-Dodecyl-6-Methoxycyclohexa-2, 5-Diene-1, 4-Dione (DMDD) isolated from Averrhoa carambola L. root, has been proven therapeutic effects on diabetic kidney disease (DKD). This research aims to assess DMDD’s effects on DKD and to investigate its underlying mechanisms, to establish DMDD as a novel pharmaceutical agent for DKD treatment. Methods: The human renal tubular epithelial (HK-2) cells were induced by high glucose (HG) to mimic DKD and followed by DMDD treatment. The cytotoxicity of DMDD was assessed using the Cell Counting Kit-8 (CCK-8) assay. The migratory capacity of HK-2 cells was evaluated through transwell and scratch-wound assays. To investigate the effect of Smad7 and miR-21–5p, lentiviral transfection was employed in HK-2 cells. Additionally, the expression of proteins related to epithelial-mesenchymal transition (EMT) and TGFβ1/Smad2/3 pathway was checked by QRT-PCR, Western blot, and immunofluorescence techniques. Results: This study has shown that DMDD significantly suppresses cell migration and the expression of Vimentin, α-SMA, TGFβ1, and p-Smad2/3 in HK-2 cells under HG conditions. Concurrently, DMDD enhances the protein expression of E-cadherin and Smad7. Intriguingly, the therapeutic effect of DMDD was abrogated upon Smad7 silencing. Further investigations revealed that DMDD effectively inhibits miR-21–5p expression, which is upregulated by HG. Downregulation of miR-21–5p inhibits the activation of the TGFβ1/Smad2/3 pathway and EMT induced by HG. In contrast, overexpression of miR-21–5p negates DMDD’s therapeutic benefits. Conclusion: DMDD mitigates EMT in HG-induced HK-2 cells by modulating the miR-21–5p/Smad7 pathway, thereby inhibiting renal fibrosis in DKD. These findings suggest that DMDD holds promise as a potential therapeutic agent for DKD