Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 13 de 13
Filter
Add more filters










Publication year range
1.
Nutrients ; 14(12)2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35745214

ABSTRACT

Obesity and overweight are closely related to diet, and the gut microbiota play an important role in body weight and human health. The aim of this study was to explore how Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032 supplementation alleviate obesity by modulating the human gut microbiome. A randomized, double-blind, placebo-controlled study was conducted on 72 individuals with overweight. Over a 12-week period, probiotic groups consumed 1 × 1010 colony-forming units of HY7601 and KY1032, whereas the placebo group consumed the same product without probiotics. After treatment, the probiotic group displayed a reduction in body weight (p < 0.001), visceral fat mass (p < 0.025), and waist circumference (p < 0.007), and an increase in adiponectin (p < 0.046), compared with the placebo group. Additionally, HY7601 and KY1032 supplementation modulated bacterial gut microbiota characteristics and beta diversity by increasing Bifidobacteriaceae and Akkermansiaceae and decreasing Prevotellaceae and Selenomonadaceae. In summary, HY7601 and KY1032 probiotics exert anti-obesity effects by regulating the gut microbiota; hence, they have therapeutic potential for preventing or alleviating obesity and living with overweight.


Subject(s)
Gastrointestinal Microbiome , Lactobacillus plantarum , Probiotics , Body Weight , Double-Blind Method , Humans , Lactobacillus , Lactobacillus plantarum/physiology , Obesity/therapy , Overweight/therapy , Triglycerides
2.
Microorganisms ; 9(12)2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34946080

ABSTRACT

Probiotics should be well established in the gut, passing through the digestive tract with a high degree of viability, and produce metabolites that improve the gut environment by interacting with the gut microbiome. Our previous study revealed that the Lactiplantibacillus plantarum HY7715 strain shows good bile acid resistance and a riboflavin production capacity. To confirm the interaction between HY7715 and gut microbiome, we performed a metabolite and microbiome study using a simulated gut system (SGS) that mimics the intestinal environment. Changes in the microbiome were confirmed and compared with L. plantarum NCDO1752 as the control. After 14 days, the HY7715 treatment group showed a relatively high butyrate content compared to the control group, which showed increased acetate and propionate concentrations. Moreover, the riboflavin content was higher in the HY7715 treatment group, whereas the NCDO1752 treatment group produced only small amounts of riboflavin during the treatment period and showed a tendency to decrease during the washout stage; however, the HY7715 group produced riboflavin continuously in the ascending colon during the washout period. A correlation analysis of the genus that increased as the content of riboflavin increased revealed butyrate-producing microorganisms, such as Blautia and Flavonifractor. In conclusion, treatment with L. plantarum HY7715 induced the production and maintenance of riboflavin and the enrichment of the intestinal microbiome.

3.
Biosens Bioelectron ; 163: 112284, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32421632

ABSTRACT

Herein, we report a novel lateral flow immunoassay (LFIA) system for detecting cardiac troponin I (cTnI) in serum using the time-resolved fluorescence resonance energy transfer (TR-FRET) technique and the fusion 5 membrane. The fusion 5 membrane is used as a strip for LFIA, and it is constructed without additional matrices (such as a sample or conjugation pad). Although this strategy for constructing the LFIA strip is quite simple and cost-effective, LFIA is still not suitable for the analysis of biomarkers that require high sensitivity, such as cTnI. Therefore, the highly sensitive TR-FRET technique is integrated with a fusion 5 membrane-based LFIA strip. To accomplish this, a microparticle covered with europium chelate-contained silica nanoparticles is synthesized as a raspberry-type particle and used as a fluorescence donor. A gold nanorod (GNR) is used as a fluorescence acceptor particle. In the TR-FRET-based LFIA system, the competitive immunoassay should be performed to satisfy the condition required for the FRET phenomenon to occur. Therefore, the fluorescence signal is proportional to the cTnI concentration, ensuring a quantitative analysis of cTnI can be accomplished by measuring the fluorescence signal between the raspberry-type europium particles and GNR. Using the developed TR-FRET-based LFIA system, sensitive detection of cTnI is successfully achieved with a limit of detection of 97 pg/mL in human serum. Moreover, because the result can be obtained using one matrix (the fusion 5 membrane), the developed LFIA system can be employed in cTnI diagnosis with a simple manufacturing process.


Subject(s)
Biosensing Techniques , Rubus , Europium , Fluorescence Resonance Energy Transfer , Humans , Immunoassay , Limit of Detection , Troponin I
4.
ACS Nano ; 13(12): 14357-14367, 2019 Dec 24.
Article in English | MEDLINE | ID: mdl-31755706

ABSTRACT

Design of freestanding electrodes incorporated with redox-active organic materials has been limited by the poor intrinsic electrical conductivity and lack of methodology driving the feasible integration of conductive substrate and the organic molecules. Single-walled carbon nanotube (SWCNT) aerogels, which possess continuous network structure and high surface area, offer a three-dimensional electrically conducting scaffold. Here, we fabricate monolithic organic electrodes by coating a nanometer-scale imide-based network (IBN) that possesses abundant redox-active sites on the 3D SWCNT scaffold. The substantially integrated 3D monolithic organic electrodes sustain high electrical conductance through a 3D electronic pathway in their compressed form (∼21 µm). A thin and controllable layer (<8 nm) of IBN organic materials has a strong adhesion onto the ultra-lightweight and conductive substrate and facilitates multielectron redox reactions to deliver a specific capacity of up to 1550 mA h g-1 (corresponding to the areal capacity of ∼2.8 mA h cm-2). The redox-active IBN in synergy with the 3D SWCNT scaffold can enable superior electrochemical performances compared to the previously reported organic-based electrode architectures and inorganic-based electrodes.

5.
Nat Commun ; 10(1): 2351, 2019 05 28.
Article in English | MEDLINE | ID: mdl-31138791

ABSTRACT

A fast-charging battery that supplies maximum energy is a key element for vehicle electrification. High-capacity silicon anodes offer a viable alternative to carbonaceous materials, but they are vulnerable to fracture due to large volumetric changes during charge-discharge cycles. The low ionic and electronic transport across the silicon particles limits the charging rate of batteries. Here, as a three-in-one solution for the above issues, we show that small amounts of sulfur doping (<1 at%) render quasi-metallic silicon microparticles by substitutional doping and increase lithium ion conductivity through the flexible and robust self-supporting channels as demonstrated by microscopy observation and theoretical calculations. Such unusual doping characters are enabled by the simultaneous bottom-up assembly of dopants and silicon at the seed level in molten salts medium. This sulfur-doped silicon anode shows highly stable battery cycling at a fast-charging rate with a high energy density beyond those of a commercial standard anode.

6.
ACS Nano ; 12(2): 1642-1649, 2018 02 27.
Article in English | MEDLINE | ID: mdl-29390179

ABSTRACT

We present a simple, versatile approach to generate highly ordered nanostructures of block copolymers (BCPs) using rubbed surfaces. A block of poly(tetrafluoroethylene) (PTFE) was dragged across a flat substrate surface above the melting point of PTFE transferring a highly aligned PTFE topographic pattern to the substrate. Si wafer, glass, and polyimide films were used as substrates. Thin films of cylinder-forming asymmetric polystyrene-block-poly(2-vinylpyridine) copolymers (S2VPs) were solvent annealed on the surfaces having the transferred surface pattern to induce their directed self-assembly. Cylinders of P2VP oriented normal to the surface are markedly aligned along the rubbing direction and used as templates to generate extremely uniform arrays of various metallic nanoparticles of gold, silver, and platinum over a large area.

7.
ACS Nano ; 12(2): 1739-1746, 2018 02 27.
Article in English | MEDLINE | ID: mdl-29350526

ABSTRACT

We show that a high energy density can be achieved in a practical manner with freestanding electrodes without using conductive carbon, binders, and current collectors. We made and used a folded graphene composite electrode designed for a high areal capacity anode. The traditional thick graphene composite electrode, such as made by filtering graphene oxide to create a thin film and reducing it such as through chemical or thermal methods, has sluggish reaction kinetics. Instead, we have made and tested a thin composite film electrode that was folded several times using a water-assisted method; it provides a continuous electron transport path in the fold regions and introduces more channels between the folded layers, which significantly enhances the electron/ion transport kinetics. A fold electrode consisting of SnO2/graphene with high areal loading of 5 mg cm-2 has a high areal capacity of 4.15 mAh cm-2, well above commercial graphite anodes (2.50-3.50 mAh cm-2), while the thickness is maintained as low as ∼20 µm. The fold electrode shows stable cycling over 500 cycles at 1.70 mA cm-2 and improved rate capability compared to thick electrodes with the same mass loading but without folds. A full cell of fold electrode coupled with LiCoO2 cathode was assembled and delivered an areal capacity of 2.84 mAh cm-2 after 300 cycles. This folding strategy can be extended to other electrode materials and rechargeable batteries.

8.
Biosensors (Basel) ; 7(4)2017 Oct 18.
Article in English | MEDLINE | ID: mdl-29057816

ABSTRACT

The use of a robust optical signaling probe with a high signal-to-noise ratio is important in the development of immunoassays. Lanthanide chelates are a promising material for this purpose, which provide time-resolved luminescence (TRL) due to their large Stokes shift and long luminescence lifetime. From this, they have attracted considerable interest in the in vitro diagnostics field. However, the direct use of lanthanide chelates is limited because their luminescent signal can be easily affected by various quenchers. To overcome this drawback, strategies that rely on the entrapment of lanthanide chelates inside nanoparticles, thereby enabling the protection of the lanthanide chelate from water, have been reported. However, the poor stability of the lanthanide-entrapped nanoparticles results in a significant fluctuation in TRL signal intensity, and this still remains a challenging issue. To address this, we have developed a Lanthanide chelate-Encapsulated Silica Nano Particle (LESNP) as a new immunosensing probe. In this approach, the lanthanide chelate is covalently crosslinked within the silane monomer during the silica nanoparticle formation. The resulting LESNP is physically stable and retains TRL properties of the parent lanthanide chelate. Using the probe, a highly sensitive, sandwich-based TRL immunoassay for the cardiac troponin I was conducted, exhibiting a limit of detection of 48 pg/mL. On the basis of the features of the LESNP such as TRL signaling capability, stability, and the ease of biofunctionalization, we expect that the LESNP can be widely applied in the development of TRL-based immunosensing.


Subject(s)
Europium/chemistry , Immunoassay/methods , Nanoparticles/chemistry , Troponin I/metabolism
9.
ACS Nano ; 10(11): 10589-10597, 2016 11 22.
Article in English | MEDLINE | ID: mdl-27934078

ABSTRACT

Three-dimensional (3D) hyperporous silicon flakes (HPSFs) are prepared via the chemical reduction of natural clay minerals bearing metal oxides. Natural clays generally have 2D flake-like structures with broad size distributions in the lateral dimension and varied thicknesses depending on the first processing condition from nature. They have repeating layers of silicate and metal oxides in various ratios. When the clay mineral is subjected to a reduction reaction, metal oxide layers can perform a negative catalyst for absorbing large amounts of exothermic heat from the reduction reaction of the silicate layers with metal reductant. Selectively etching out metal oxides shows a hyperporous nanoflake structure containing 100 nm macropores and meso-/micropores on its framework. The resultant HPSFs are demonstrated as anode materials for lithium-ion batteries. Compared to conventional micro-Si anodes, HPSFs exhibit exceptionally high initial Coulombic efficiency over 92%. Furthermore, HPSF anodes show outstanding cycling performance (reversible capacity of 1619 mAh g-1 at a rate of 0.5 C after 200 cycles, 95.2% retention) and rate performance (∼580 mAh g-1 at a rate of 10 C) owing to their distinctive structure.

10.
Chem Commun (Camb) ; 52(67): 10221-4, 2016 Aug 11.
Article in English | MEDLINE | ID: mdl-27383444

ABSTRACT

3D multi-stacked hyperporous silicon flakes (MHSFs) are prepared via a selective chemical reduction of natural clay minerals bearing MgO negative catalyst layers. The resultant MHSFs are used as a photocatalyst for solar-driven hydrogen evolution and exhibit the highest photocatalytic acitivty (1031 µmol H2 h(-1) g(-1) Si) coupled with a Pt cocatalyst.

11.
Small ; 12(23): 3119-27, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27119208

ABSTRACT

It is known that grafting one polymer onto another polymer backbone is a powerful strategy capable of combining dual benefits from each parent polymer. Thus amphiphilic graft copolymer precursors (poly(vinylidene difluoride)-graft-poly(tert-butylacrylate) (PVDF-g-PtBA)) have been developed via atom transfer radical polymerization, and demonstrated its outstanding properties as a promising binder for high-performance lithium-ion battery (LIB) by using in situ pyrolytic transformation of PtBA to poly(acrylic acid) segments. In addition to its superior mechanical properties and accommodation capability of volume expansion, the Si anode with PVDF-g-PtBA exhibits the excellent charge and discharge capacities of 2672 and 2958 mAh g(-1) with the capacity retention of 84% after 50 cycles. More meaningfully, the graft copolymer binder shows good operating characteristics in both LiN0.5 M1.5 O4 cathode and neural graphite anode, respectively. By containing such diverse features, a graft copolymer-loaded LiN0.5 M1.5 O4 /Si-NG full cell has been successfully achieved, which delivers energy density as high as 546 Wh kg(-1) with cycle retention of ≈70% after 50 cycles (1 C). For the first time, this work sheds new light on the unique nature of the graft copolymer binders in LIB application, which will provide a practical solution for volume expansion and low efficiency problems, leading to a high-energy-density lithium-ion chemistry.

12.
ACS Nano ; 10(2): 2843-51, 2016 Feb 23.
Article in English | MEDLINE | ID: mdl-26789405

ABSTRACT

Two-dimensional Si nanosheets have been studied as a promising candidate for lithium-ion battery anode materials. However, Si nanosheets reported so far showed poor cycling performances and required further improvements. In this work, we utilize inexpensive natural clays for preparing high quality Si nanosheets via a one-step simultaneous molten salt-induced exfoliation and chemical reduction process. This approach produces high purity mesoporous Si nanosheets in high yield. As a control experiment, two-step process (pre-exfoliated silicate sheets and subsequent chemical reduction) cannot sustain their original two-dimensional structure. In contrast, one-step method results in a production of 5 nm-thick highly porous Si nanosheets. Carbon-coated Si nanosheet anodes exhibit a high reversible capacity of 865 mAh g(-1) at 1.0 A g(-1) with an outstanding capacity retention of 92.3% after 500 cycles. It also delivers high rate capability, corresponding to a capacity of 60% at 20 A g(-1) compared to that of 2.0 A g(-1). Furthermore, the Si nanosheet electrodes show volume expansion of only 42% after 200 cycles.

13.
Biochem Biophys Res Commun ; 392(1): 9-15, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-20043881

ABSTRACT

Non-viral gene delivery is a safe and suitable alternative to viral vector-mediated delivery to overcome the immunogenicity and tumorigenesis associated with viral vectors. Using the novel, human-origin Hph-1 protein transduction domain that can facilitate the transduction of protein into cells, we developed a new strategy to deliver naked DNA in vitro and in vivo. The new DNA delivery system contains Hph-1-GAL4 DNA-binding domain (DBD) fusion protein and enhanced green fluorescent protein (EGFP) reporter plasmid that includes the five repeats of GAL4 upstream activating sequence (UAS). Hph-1-GAL4-DBD protein formed complex with plasmid DNA through the specific interaction between GAL4-DBD and UAS, and delivered into the cells via the Hph-1-PTD. The pEGFP DNA was successfully delivered by the Hph-1-GAL4 system, and the EGFP was effectively expressed in mammalian cells such as HeLa and Jurkat, as well as in Bright Yellow-2 (BY-2) plant cells. When 10 microg of pEGFP DNA was intranasally administered to mice using Hph-1-GAL4 protein, a high level of EGFP expression was detected throughout the lung tissue for 7 days. These results suggest that an Hph-1-PTD-mediated DNA delivery strategy may be an useful non-viral DNA delivery system for gene therapy and DNA vaccines.


Subject(s)
Carrier Proteins/metabolism , DNA-Binding Proteins/metabolism , DNA/metabolism , Recombinant Fusion Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Transcription Factors/metabolism , Transduction, Genetic/methods , Carrier Proteins/genetics , DNA/genetics , DNA-Binding Proteins/genetics , HeLa Cells , Humans , Polycomb Repressive Complex 1 , Recombinant Fusion Proteins/genetics , Saccharomyces cerevisiae Proteins/genetics , Transcription Factors/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...