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1.
Immunity ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31604687

RESUMO

Generation of the first T lymphocytes in the human embryo involves the emergence, migration, and thymus seeding of lymphoid progenitors together with concomitant thymus organogenesis, which is the initial step to establish the entire adaptive immune system. However, the cellular and molecular programs regulating this process remain unclear. We constructed a single-cell transcriptional landscape of human early T lymphopoiesis by using cells from multiple hemogenic and hematopoietic sites spanning embryonic and fetal stages. Among heterogenous early thymic progenitors, one subtype shared common features with a subset of lymphoid progenitors in fetal liver that are known as thymus-seeding progenitors. Unbiased bioinformatics analysis identified a distinct type of pre-thymic lymphoid progenitors in the aorta-gonad-mesonephros (AGM) region. In parallel, we investigated thymic epithelial cell development and potential cell-cell interactions during thymus organogenesis. Together, our data provide insights into human early T lymphopoiesis that prospectively direct T lymphocyte regeneration, which might lead to development of clinical applications.

2.
IET Nanobiotechnol ; 13(8): 880-886, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31625531

RESUMO

In this study, the authors developed pectin-stabilised selenium nanoparticles (pectin-SeNPs) for curcumin (Cur) encapsulation and evaluated their physicochemical properties and biological activities. Results showed that pectin-SeNPs and Cur-loaded pectin-SeNPs (pectin-SeNPs@Cur) exhibited monodisperse and homogeneous spherical structures in aqueous solutions with mean particle sizes of ∼61 and ∼119 nm, respectively. Cur was successfully encapsulated into pectin-SeNPs through hydrogen bonding interactions with an encapsulation efficiency of ∼60.6%, a loading content of ∼7.4%, and a pH-dependent and controlled drug release in vitro. After encapsulation was completed, pectin-SeNPs@Cur showed enhanced water solubility (∼500-fold), dispersibility, and storage stability compared with those of free Cur. Moreover, pectin-SeNPs@Cur possessed significant free radical scavenging ability and antioxidant capacity in vitro, which were stronger than those of pectin-SeNPs. Antitumour activity assay in vitro demonstrated that pectin-SeNPs@Cur could inhibit the growth of HepG2 cells in a concentration-dependent manner, and the nanocarrier pectin-SeNPs exhibited a low cytotoxic activity against HepG2 cells. Therefore, the results suggested that pectin-SeNPs could function as effective nanovectors for the enhancement of the water solubility, stability, and in vitro bioactivities of hydrophobic Cur.

3.
Environ Sci Technol ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31661968

RESUMO

To investigate the characteristics of historic-use organochlorine pesticides (OCPs) in the marginal seawater of China, we examined the seasonal and spatial distributions of hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethane (DDTs) in the northern South China Sea (NSCS, 18-23° N) and East China Sea (ECS, 26-32° N). Seasonally, in the NSCS, the significantly higher concentrations (p < 0.05) of HCB, HCHs, and DDTs were found in summer, autumn, and summer through autumn, respectively. In the ECS, the higher concentrations were found in summer through winter, autumn, and summer, respectively. Spatially, HCB concentrations were significantly higher in the NSCS than in the ECS during all seasons except winter. During all four seasons, concentrations of HCHs were significantly higher in the NSCS than in the ECS. In summer and autumn, concentrations of DDTs were significantly higher in the NSCS than in the ECS, while no significant differences were found in spring and winter. Generally, regional usage, river-influenced coastal plumes, phytoplankton abundances, and ocean currents played crucial roles in the input, transport, degradation, and dilution of OCPs, respectively. These dynamic factors along with the seasonally alternating monsoon directly influenced the seasonal and spatial characteristics of OCPs. Furthermore, the profiles and diagnostic ratios of HCHs and DDTs revealed highly weathered OCP residues, attributed to eroded soils carried by surface runoff and long-range oceanic and atmospheric transport.

4.
Mol Ther Nucleic Acids ; 18: 308-319, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614321

RESUMO

Growing tumor cells possess a distinct metabolic phenomenon that allows them to preferentially utilize glucose through aerobic glycolysis, which is referred to as the "Warburg effect." Accumulating evidence suggests that microRNAs (miRNAs) could regulate such metabolic reprogramming. Our microarray analysis and quantitative real-time PCR validation revealed that miR-885-5p was strongly downregulated in hepatocellular carcinoma (HCC) tissues and cell lines. To investigate miR-885-5p's biological functions in HCC progression, malignant phenotypes were analyzed in different types of hypoxic model and indicated that overexpression of miR-885-5p significantly inhibited HCC cell proliferation and migration and induced apoptosis in vitro and tumor growth in vivo. Subsequent investigations of whether miR-885-5p regulated the glycometabolic activity of cancer cells demonstrated that forced expression of miR-885-5p in SMMC-7721 cells significantly reduced glucose uptake and lactate production by repressing several key enzymes related to glycolysis. Particularly, miR-885-5p directly targets the 3' UTR of hexokinase 2 (HK2), which is a key enzyme that catalyzes the irreversible first step of glycolysis and associates with poor patient outcomes. The miR-885-5p/HK2 axis strongly links aerobic glycolysis to carcinogenesis and may become a promising therapeutic target and prognostic predictor for HCC patients.

5.
Comput Math Methods Med ; 2019: 8617503, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662790

RESUMO

In this work, an ontology-based model for AI-assisted medicine side-effect (SE) prediction is developed, where three main components, including the drug model, the treatment model, and the AI-assisted prediction model, of the proposed model are presented. To validate the proposed model, an ANN structure is established and trained by two hundred forty-two TCM prescriptions. These data are gathered and classified from the most famous ancient TCM book, and more than one thousand SE reports, in which two ontology-based attributions, hot and cold, are introduced to evaluate whether the prescription will cause SE or not. The results preliminarily reveal that it is a relationship between the ontology-based attributions and the corresponding predicted indicator that can be learnt by AI for predicting the SE, which suggests the proposed model has a potential in AI-assisted SE prediction. However, it should be noted that the proposed model highly depends on the sufficient clinic data, and hereby, much deeper exploration is important for enhancing the accuracy of the prediction.

6.
ACS Appl Mater Interfaces ; 11(43): 40781-40792, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31588726

RESUMO

Metal-organic framework (MOF)-derived composites on the microwave absorption have received extensive attention. However, which kind of organic ligand corresponding MOF derivative has better electromagnetic wave absorption performance is an urgent problem to be solved. In this work, two kinds of Ni@C derived from the Ni-based MOFs with two kinds of organic ligands (dimethylimidazole as a ligand named as Ni-ZIF and trimesic acid as a ligand named as Ni-BTC) were successfully obtained. The compositions, morphologies, and electromagnetic properties of two composites were well controlled. As a result, both kinds of Ni@C exhibited the good microwave absorption properties. Comparatively speaking, the Ni@C derived from Ni-ZIF performs better. The Ni@C-ZIF microspheres with a 40% mass filling ratio exhibited a strong reflection loss of -86.8 dB at 13.2 GHz when the matching thickness was 2.7 mm, and the corresponding effective absorption bandwidth was 7.4 GHz (4-11.4 GHz) with the thickness ranging from 1.5 to 4.0 mm. The impedance matching, multiple reflection, and interfacial polarization among Ni and C were beneficial to the enhancement of microwave attenuation, which N-doping introduced by nitrogen-containing ligands leads to excellent microwave absorption properties. Therefore, this work can give insights into understanding the absorbing mechanism as well as provide a simple and flexible paradigm for the design and synthesis of the absorber with the tunable and high-efficiency performances.

7.
Cancer Lett ; 469: 78-88, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31629931

RESUMO

Selective estrogen receptor modulators (SERMs) are a class of structurally diverse compounds, which have been extensively used to treat hormone-responsive cancers due to their unique partially agonistic and antagonistic properties toward estrogen receptors. Our previous studies have identified a three-dimensional SERM, oxabicycloheptene sulfonate (OBHS), as an estrogen receptor α (ERα) ligand, which is effective for the prevention and treatment of estrogen-dependent endometriosis in vivo. Here, using genome-wide ChIP-seq and RNA-seq analysis, we report that OBHS rapidly induces genome-wide ERα occupancy and acts as a partial agonist and antagonist for ERα. Interestingly, OBHS downregulates the homologous recombination and repair (HRR) modules, resulting in increased DNA damage, apoptosis and cell cycle arrest, inducing synthetic lethality with poly (ADP-ribose) polymerase (PARP) inhibitor olaparib through ERα antagonism. Mechanistically, OBHS impairs the RNA polymerase II (Pol II) loading at the promoters of estrogen-responsive HRR genes. Furthermore, combination therapy of OBHS with olaparib significantly reduces the tumour burden and delays the progression of breast cancer in vivo. Together, our studies not only characterise a novel SERM which uniquely targets the homologous recombination and repair programmes through ERα antagonism but also propose a synthetic lethal strategy by combining OBHS with PARP inhibitor olaparib for ERα-responsive cancers.

8.
J Cell Mol Med ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657880

RESUMO

Solid tumour frequently undergoes metabolic stress during tumour development because of inadequate blood supply and the high nutrient expenditure. p53 is activated by glucose limitation and maintains cell survival via triggering metabolic checkpoint. However, the exact downstream contributors are not completely identified. BAG3 is a cochaperone with multiple cellular functions and is implicated in metabolic reprogramming of pancreatic cancer cells. The current study demonstrated that glucose limitation transcriptionally suppressed BAG3 expression in a p53-dependent manner. Importantly, hinderance of its down-regulation compromised cellular adaptation to metabolic stress triggered by glucose insufficiency, supporting that BAG3 might be one of p53 downstream contributors for cellular adaptation to metabolic stress. Our data showed that ectopic BAG3 expression suppressed p53 accumulation via direct interaction under metabolic stress. Thereby, the current study highlights the significance of p53-mediated BAG3 suppression in cellular adaptation to metabolic stress via facilitating p53 accumulation.

9.
Oxid Med Cell Longev ; 2019: 5276096, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31612074

RESUMO

Calorie restriction (CR) is a nongenetic intervention with a robust effect on delaying aging in mammals and other organisms. A mild stimulation on mitochondrial biogenesis induced by CR seems to be an important action mode for its benefits. Here, we reported that a component isolated from Rhodiola rosea L., salidroside, delays replicative senescence in human fibroblasts, which is related to its stimulation on mitochondrial biogenesis by activating SIRT1 partly resulted from inhibition on miR-22. Salidroside increased the mitochondrial mass that accompanied an increment of the key regulators of mitochondrial biogenesis including PGC-1α, NRF-1, and TFAM and reversed the mitochondrial dysfunction in presenescent 50PD cells, showing a comparable effect to that of resveratrol. SIRT1 is involved in the inducement of mitochondrial biogenesis by salidroside. The declined expression of SIRT1 in 50PD cells compared with the young 30PD cells was prevented upon salidroside treatment. In addition, pretreatment of EX-527, a selective SIRT1 inhibitor, could block the increased mitochondrial mass and decreased ROS production induced by salidroside in 50PD cells, resulting in an accelerated cellular senescence. We further found that salidroside reversed the elevated miR-22 expression in presenescent cells according to a miRNA array analysis and a subsequent qPCR validation. Enforced miR-22 expression by using a Pre-miR-22 lentiviral construct induced the young fibroblasts (30PD) into a senescence state, accompanied with increased senescence-related molecules including p53, p21, p16, and decreased SIRT1 expression, a known target of miR-22. However, salidroside could partly impede the senescence progression induced by lenti-Pre-miR-22. Taken together, our data suggest that salidroside delays replicative senescence by stimulating mitochondrial biogenesis partly through a miR22/SIRT1 pathway, which enriches our current knowledge of a salidroside-mediated postpone senility effect and provides a new perspective on the antidecrepitude function of this naturally occurring compound in animals and humans.

10.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(9): 1160-1162, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31657345

RESUMO

OBJECTIVE: Sepsis includes a highly diverse and dynamic mixture of systemic inflammatory response syndrome (SIRS) and compensatory anti-inflammatory response syndrome (CARS). In the past, drugs produced to block the early inflammatory response had little effect on reversing the development of sepsis. Recent studies have shown that the mortality and prognosis of patients are significantly correlated with the immunosuppression of sepsis and the overexpression of co-inhibitory molecules. Programmed death-1 (PD-1) is a recently focused co-inhibitory molecule, which can regulate the functions of a variety of immune cells and participate in innate immunity and acquired immunity. It has important value in risk stratification and prognosis prediction of patients with sepsis, and can be used as one of the intervention targets for immune regulation in sepsis in the future. The role of PD-1 signaling pathway in immunosuppression and its effect on patients' prognosis is reviewed in this article, providing new directions for the treatment of sepsis.


Assuntos
Sepse , Síndrome de Resposta Inflamatória Sistêmica , Humanos , Imunidade Inata , Imunossupressão , Transdução de Sinais
11.
Neuroimage ; 203: 116180, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31520745

RESUMO

The ability to conceive time is a corner stone of human cognition. It is unknown, however, whether time conceptualisation differs depending on language of operation in bilinguals. Whilst both Chinese and English cultures associate the future with the front space, some temporal expressions of Chinese involve a configuration reversal due to historic reasons. For instance, Chinese refers to the day after tomorrow using the spatiotemporal metaphor hou-tian - 'back-day' and to the day before yesterday using qian-tian - 'front-day'. Here, we show that native metaphors interfere with time conceptualisation when bilinguals operate in the second language. We asked Chinese-English bilinguals to indicate whether an auditory stimulus depicted a day of the week either one or two days away from the present day, irrespective of whether it referred to the past or the future, and ignoring whether it was presented through loudspeakers situated in the back or the front space. Stimulus configurations incongruent with spatiotemporal metaphors of Chinese (e.g., "Friday" presented in the front of the participant during a session held on a Wednesday) were conceptually more challenging than congruent configurations (e.g., the same stimulus presented in their back), as indexed by N400 modulations of event-related brain potentials. The same pattern obtained for days or years as stimuli, but surprisingly, it was found only when participants operated in English, not in Chinese. We contend that the task was easier and less prone to induce cross-language activation when conducted in the native language. We thus show that, when they operate in the second language, bilinguals unconsciously retrieve irrelevant native language representations that shape time conceptualisation in real time.

12.
Theranostics ; 9(19): 5610-5625, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534506

RESUMO

Photothermal therapy as novel strategy to convert near-infrared (NIR) light into heat for treatment cancers has attracted great attention and been widely studied. However, side effects and low efficiency remain the main challenge of precise cancer photothermal therapy. Methods: In this study, we have successfully fabricated and characterized the dual-targeted gold nanoprisms, whereby bare gold nanoprisms (Au NPR) were conjugated to a phenanthroline derivatives-functionalized tetraphenylethene (TPE) and further stabilized with target peptide aptamers via Au-S bonds (Au-Apt-TPE). Then, the remaining nitrogen atoms of the Au-Apt-TPE could effectively chelate with Zn2+ ions (Au-Apt-TPE@Zn) for monitoring early stage apoptotic cells. Results: The as-synthesized Au-Apt-TPE@Zn exhibited good monodispersity, size stability and consistent spectral characteristics. TPE synthesized here showed aggregation-induced emission (AIE) characteristics, and zinc conjunction (TPE@Zn) endowed Au-Apt-TPE@Zn with the cell membrane-targeted ability to selectively recognize the membranes of early stage apoptotic cells but not respond to healthy cells, which provided valuable diagnosis information on therapeutic efficacy. Au-Apt-TPE@Zn achieved specifically nuclear-targeted ability by surface decoration of AS1411 DNA aptamer. Au-Apt-TPE@Zn under NIR irradiation showed effective photothermal therapy against SGC-7901 human gastric carcinoma cells growth in vitro by inducing apoptosis through triggering reactive oxygen species (ROS) overproduction and regulating multiple signal crosstalk. In vivo studies revealed that Au-Apt-TPE@Zn under NIR irradiation showed deep penetration and dual-model imaging application (cancer-targeted fluorescence imaging and light-up photoacoustic imaging). Au-Apt-TPE@Zn under NIR irradiation also displayed strong photothermal therapy against gastric carcinoma xenograft growth in vivo by induction of apoptosis. Importantly, analysis of histopathology, hematotoxicity and immunocytotoxicity indicated that Au-Apt-TPE@Zn had less side effect and high biocompatibility. Conclusions: Our findings validated the design of using Au nanoprism with AIE materials and dual-targeted decoration could be an effective strategy in recognition of early apoptosis, dual-model imaging and precise cancer photothermal therapy.

13.
Food Res Int ; 125: 108552, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31554084

RESUMO

A rapid and non-destructive ultrasonic pulse echo system was developed for vegetable oils characterization. To understand the differences in the ultrasonic properties of the oils, physical traits, such as their viscosity and density, were related to the ultrasonic data. In turn, these physical traits were correlated with the fatty acid compositions of the oils. Eighty oil samples, including 30 extra virgin olive oil (EVOO), 15 refined olive oil, 15 pomace olive oil, 10 rapeseed oil, 5 sunflower oil and 5 peanut oil samples, were analysed for their sound properties, viscosities, densities and fatty acid compositions. It was observed that the ultrasonic velocity of EVOO decreased linearly with increase in temperature, the temperature coefficient of ultrasonic velocity in EVOO was -2.92 m·s-1·°C-1. The ultrasonic velocity of EVOO (1453 ±â€¯2 m/s) differed significantly from those of pomace olive oil and the oils of other botanical origin, but not from the velocity of refined olive oil. Ultrasonic velocity was positively correlated with the density and negatively correlated with the viscosity of the oils. The higher density and lower viscosity of the oils were in turn related to a higher unsaturation degree of the oils. Hence, oils with a higher proportion of unsaturated fat present higher densities and lower viscosities, which resulted in higher ultrasonic velocity values. Ultrasonic measurements allow rapid, non-destructive analysis, and this first application for characterization of these oils is promising.

14.
Oncogene ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501523

RESUMO

TRIM family proteins are defined as E3 ubiquitin ligases because of their RING-finger domains. The ubiquitin-like protein interferon-stimulated gene 15 (ISG15) encodes a 15-kDa protein, that is implicated in the posttranslational modification of diverse proteins. Both TRIM29 and ISG15 play both pro-tumoral and anti-tumoral functions in cancer cells derived from different histology. In the current study, we demonstrated that correlation expression of TRIM29 and ISG15 in pancreatic ductal adenocarcinomas (PDACs). The current study demonstrated that TRIM29 knockdown destabilized ISG15 protein via promoting its processing by calpain 3 (CAPN3). Importantly, the current study found that TRIM29 knockdown suppressed cancer stem cell-like features of PDACs, which can be rescued by ISG15 independent of its conjugation function. In addition, the current study demonstrated that extracellular free ISG15 played an important role in maintenance of cancer stem cell-like features of PDACs. Thereby, the current study displayed a novel mechanism by which TRIM29 modulates ISG15 stability via CAPN3-mediated processing, and subsequently extracellular ISG15 maintains the cancer stem cell-like features of PDAC via autocrine mode of action.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31471556

RESUMO

BACKGROUNDS: p53 is a tumor suppressor that prevents cancer onset and progression, and mutations in the p53 gene cause loss of the tumor suppressor function of the protein. The mutant p53 protein in tumor cells can form aggregates which contribute to the dominant-negative effect over the wild-type p53 protein, causing loss of p53 tumor suppression or gain of novel oncogenic functions. Mutations in p53 have been implicated in the pathogenesis of primary prostate cancer (PCa), and are often detected in recurrent and metastatic disease. Thus, targeting mutant p53 may constitute an alternative therapeutic strategy for advanced PCa for which there are no other viable options. METHODS: In this study, we used immunoprecipitation, immunofluorescence, clonogenic survival, and cell proliferation assays, flow cytometric analysis and in vivo xenograft to investigate the biological effects of ReACp53, a cell-permeable peptide inhibitor of p53 aggregation, on mutant p53-carrying PCa cells. RESULTS: Our results show that ReACp53 targets amyloid aggregates of mutant p53 protein and restores the p53 nuclear function as transcriptional factor, induces mitochondrial cell death and reduces DNA synthesis of mutant p53-carrying PCa cells; ReACp53 also inhibits xenograft tumor growth in vivo. CONCLUSIONS: The data presented here suggest a therapeutic potential of targeting mutant p53 protein in advanced PCa setting, which has a clinical impact for aggressive PCa with transforming how such tumors are managed.

16.
Cell Mol Life Sci ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486849

RESUMO

Cysteine and aromatic residues are major structure-promoting residues. We assessed the abundance, structural coverage, and functional characteristics of the "non-smelly" proteins, i.e., proteins that do not contain cysteine residues (C-depleted) or cysteine and aromatic residues (CFYWH-depleted), across 817 proteomes from all domains of life. The analysis revealed that although these proteomes contained significant levels of the C-depleted proteins, with prokaryotes being significantly more enriched in such proteins than eukaryotes, the CFYWH-depleted proteins were relatively rare, accounting for about 0.05% of proteomes. Furthermore, CFYWH-depleted proteins were virtually never found in PDB. Depletion in cysteine and in aromatic residues was associated with the substantially increased intrinsic disorder levels across all domains of life. Archaeal and eukaryotic organisms with higher levels of the C-depleted proteins were shown to have higher levels of the intrinsic disorder and lower levels of structural coverage. We also showed that the "non-smelly" proteins typically did not independently fold into monomeric structures, and instead, they fold by interacting with nucleic acids as constituents of the ribosome and nucleosome complexes. They were shown to be involved in translation, transcription, nucleosome assembly, transmembrane transport, and protein folding functions, all of which are known to be associated with the intrinsic disorder. Our data suggested that, in general, structure of monomeric proteins is crucially dependent on the presence of cysteine and aromatic residues.

17.
Colloids Surf B Biointerfaces ; 183: 110450, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31472388

RESUMO

Extracellular polymeric substances (EPS) contain a vast number of functional groups which can provide sorption sites for heavy metal cations in solution, however, the mechanisms for the interaction of EPS with various metal cations were not well understood. In this study, the sorption potential of EPS from Pseudomonas fluorescens for different cations was investigated. The changes of electrokinetic properties that occurred on the surface of EPS once they adsorbed these cations were also studied using zeta potential measurements as a function of pH and cation concentration. The adsorption data fitted Freundlich isotherm better than Langmuir and D-R isotherms. The interactions of the cations with EPS were favourable with the separation factor Kr < 1. Under different pH conditions, the zeta potential of EPS in the different cation solution followed the order: Fe(III) (at pH ≤ 5.0) > Al(III) > Cu(II) > Mn(II) > Ni(II)≈Cd(II) > Ca(II) > EPS, while with respect to the initial cation concentration, the zeta potential of EPS was in the order: Fe(III) > Al(III) > Cu(II) > Cd(II) > Ni(II)≈Mn(II)≈Ca(II). The effect of cation sorption on the surface charge of EPS increased with pH as well as cation concentration. The thermodynamic analysis demonstrated that besides the sorption of Fe which was exothermic, all the other cations were adsorbed through an endothermic process. The ΔSads revealed that most of the cations interacted with EPS through the formation of inner-sphere complexes. The ATR-FTIR analyses confirmed that complexation occurred between the cations and functional groups on the surface of EPS. The zeta potential of EPS shifted to positive value direction due to sorption of cations on EPS, indicating that the specific interactions were involved in the sorption process. This study enhances our understanding of EPS aggregation and heavy metal bio-sorption through the electrokinetic mechanism. The results will provide useful references for immobilization of heavy metals and alleviation of Al toxicity in acidic soils.

18.
Food Funct ; 10(9): 5574-5586, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31432066

RESUMO

The antidiabetic activity and potential underlying mechanism of a polysaccharide-protein (PSP) complex from Corbicula fluminea were determined in streptozotoxin (STZ)-induced diabetic rats. PSP exhibited inhibitory activity (in vitro) against α-glucosidase and α-amylase via a reversible competitive inhibition pattern with a stronger inhibition for α-glucosidase. Dietary administration of PSP had potential antidiabetic activities in vivo, which was evidenced by the fact that PSP alleviates body weight loss and organ injuries, reduced fasting blood glucose levels, elevated glucose tolerance, and ameliorated lipid metabolism and hepatic functions, as well as attenuated oxidative stress in STZ-treated diabetic rats. Furthermore, our results demonstrated that the antidiabetic activities of PSP were associated with the activation of the phosphoinositide 3-kinase/protein kinase B signaling pathway in STZ-treated rats. These findings supported the potential of PSP to be used as a functional ingredient in the preparation of functional and medicinal foods to inhibit diabetes mellitus and its complications.

19.
Food Chem ; 298: 124987, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260962

RESUMO

In this study, subcritical water extraction (SWE), SWE in aqueous citric acid (pH 5.0) (SWEC), and ultrasound-assisted SWEC (USWEC) were used to extract soluble dietary fiber (SDF) from wheat bran. Results showed that SWE-based methods significantly influenced the physicochemical, functional, and biological properties of the SDF. The fraction SDF-III attained via USWEC had higher SDF yield (46.30%) and carbohydrate content (82.91%), and lower weight-average molecular weight (65.2 kDa) and particle size (1.17 µm), and looser and more porous surface structure, compared with the SDF-I and SDF-II obtained by SWE and SWEC, respectively. USWEC increased the thermal stability and homogeneity of SDF-III but decreased its apparent viscosity and dynamic viscoelasticity. Moreover, the SDF-III exhibited more significant antioxidant and α-amylase inhibitory activities in vitro than SDF-I and SDF-II. Therefore, the USWEC technique had a greater potential for the highly-efficient production of SDF from wheat bran.


Assuntos
Fracionamento Químico/métodos , Fibras na Dieta , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Cítrico/química , Fibras na Dieta/farmacologia , Difusão Dinâmica da Luz , Inibidores Enzimáticos/farmacologia , Concentração de Íons de Hidrogênio , Peso Molecular , Monossacarídeos/análise , Tamanho da Partícula , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Água/química , alfa-Amilases/antagonistas & inibidores
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