Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 301
Filtrar
1.
Nature ; 632(8025): 528-535, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39048826

RESUMO

Conjugated polymers promise inherently flexible and low-cost thermoelectrics for powering the Internet of Things from waste heat1,2. Their valuable applications, however, have been hitherto hindered by the low dimensionless figure of merit (ZT)3-6. Here we report high-ZT thermoelectric plastics, which were achieved by creating a polymeric multi-heterojunction with periodic dual-heterojunction features, where each period is composed of two polymers with a sub-ten-nanometre layered heterojunction structure and an interpenetrating bulk-heterojunction interface. This geometry produces significantly enhanced interfacial phonon-like scattering while maintaining efficient charge transport. We observed a significant suppression of thermal conductivity by over 60 per cent and an enhanced power factor when compared with individual polymers, resulting in a ZT of up to 1.28 at 368 kelvin. This polymeric thermoelectric performance surpasses that of commercial thermoelectric materials and existing flexible thermoelectric candidates. Importantly, we demonstrated the compatibility of the polymeric multi-heterojunction structure with solution coating techniques for satisfying the demand for large-area plastic thermoelectrics, which paves the way for polymeric multi-heterojunctions towards cost-effective wearable thermoelectric technologies.

2.
Small ; 20(33): e2401080, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38566553

RESUMO

Non-fullerene acceptors (NFAs) significantly enhance photovoltaic performance in organic solar cells (OSCs) using halogenated solvents and additives. However, these solvents are environmentally detrimental and unsuitable for industrial-scale production, and the issue of OSCs' poor long-term stability persists. This report introduces eight asymmetric NFAs (IPCnF-BBO-IC2F, IPCnF-BBO-IC2Cl, IPCnCl-BBO-IC2F, and IPCnCl-BBO-IC2Cl, where n = 1 and 2). These NFAs comprise a 12,13-bis(2-butyloctyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno-[3,2-b]indole (BBO) core. One end of the core attaches to a mono- or di-halogenated 9H-indeno[1,2-b]pyrazine-2,3-dicarbonitrile (IPC) end group (IPC1F, IPC1Cl, IPC2F, or IPC2Cl), while the other end connects to a 2-(5,6-dihalo-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (IC) end group (IC2F or IC2Cl). The optical and electronic properties of these NFAs can be finely tuned by controlling the number of halogen atoms. Crucially, these NFAs demonstrate excellent compatibility with PM6 even in o-xylene, facilitating the production of additive-free OSCs. The di-halogenated IPC-based NFAs outperform their mono-halogenated counterparts in photovoltaic performance within OSCs. Remarkably, the di-halogenated IPC-based NFAs maintain 94‒98% of their initial PCEs over 2000 h in air without encapsulation, indicating superior long-term device stability. These findings imply that the integration of di-halogenated IPCs in asymmetric NFA design offers a promising route to efficient, stable OSCs manufactured through environmentally friendly processes.

3.
Medicina (Kaunas) ; 59(6)2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37374325

RESUMO

Background and Objectives: This study aimed to evaluate the added value of cone-beam computed tomography (CBCT) for detecting hepatocellular carcinomas (HCC) and feeding arteries during transcatheter arterial chemoembolization (TACE). Material and methods: Seventy-six patients underwent TACE and CBCT. We subcategorized patients into groups I (61 patients: possible superselection of tumor/feeding arteries) and II (15 patients: limited superselection of tumor/feeding arteries). We evaluated fluoroscopy time and radiation dose during TACE. Two blinded radiologists independently performed an interval reading based on digital subtraction angiography (DSA) imaging only and DSA combined with CBCT in group I. Result: The mean total fluoroscopy time was 1456.3 ± 605.6 s. The mean dose-area product (DAP), mean DAP of CBCT, and mean ratio of DAP of CBCT to total DAP was 137.1 ± 69.2 Gy cm2, 18.3 ± 7.1 Gy cm2, and 13.3%, respectively. The sensitivity for detecting HCC increased after the additional CBCT reading, from 69.6% to 97.3% and 69.6% to 96.4% for readers 1 and 2, respectively. The sensitivity for detecting feeding arteries increased from 60.3% to 96.6% and 63.8% to 97.4% for readers 1 and 2, respectively. Conclusions: CBCT can increase sensitivity for detecting HCCs and feeding arteries without significantly increasing the radiation exposure.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Exposição à Radiação , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Artérias/patologia , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos Retrospectivos
4.
Proteomics ; 22(3): e2100125, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34596327

RESUMO

Akkermansia muciniphila is a prominent mucin-degrading bacterium that acts as a keystone species in regulating the human gut microbiota. Despite recently increasing research into this bacterium and its relevance to human health, a high-resolution database of its functional proteins remains scarce. Here, we provide a proteomic overview of A. muciniphila grown in different nutrient conditions ranging from defined to complex. Of 2318 protein-coding genes in the genome, we identified 841 (40%) that were expressed at the protein level. Overall, proteins involved in energy production and carbohydrate metabolism indicate that A. muciniphila relies mainly on the Embden-Meyerhof-Parnas pathway, and produces short-chain fatty acids through anaerobic fermentation in a nutrient-specific manner. Moreover, this bacterium possesses a broad repertoire of glycosyl hydrolases, together with putative peptidases and sulfatases, to cleave O-glycosylated mucin. Of them, putative mucin-degrading enzymes (Amuc_1220, Amuc_1120, Amuc_0052, Amuc_0480, and Amuc_0060) are highly abundant in the mucin-supplemented media. Furthermore, A. muciniphila uses mucin-derived monosaccharides as sources of energy and cell wall biogenesis. Our dataset provides nutrient-dependent global proteomes of A. muciniphila ATCC BAA-835 to offer insights into its metabolic functions that shape the composition of the human gut microbiota via mucin degradation.


Assuntos
Mucinas , Proteômica , Akkermansia , Humanos , Mucinas/metabolismo , Nutrientes , Verrucomicrobia/metabolismo
5.
J Cell Physiol ; 237(4): 2155-2168, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35048384

RESUMO

The fibroblast growth factor (FGF)/FGF receptor (FGFR) signaling pathway plays important roles in the development and growth of the skeleton. Apert syndrome caused by gain-of-function mutations of FGFR2 results in aberrant phenotypes of the skull, midface, and limbs. Although short limbs are representative features in patients with Apert syndrome, the causative mechanism for this limb defect has not been elucidated. Here we quantitatively confirmed decreases in the bone length, bone mineral density, and bone thickness in the Apert syndrome model of gene knock-in Fgfr2S252W/+ (EIIA-Fgfr2S252W/+ ) mice. Interestingly, despite these bone defects, histological analysis showed that the endochondral ossification process in the mutant mice was similar to that in wild-type mice. Tartrate-resistant acid phosphatase staining revealed that trabecular bone loss in mutant mice was associated with excessive osteoclast activity despite accelerated osteogenic differentiation. We investigated the osteoblast-osteoclast interaction and found that the increase in osteoclast activity was due to an increase in the Rankl level of osteoblasts in mutant mice and not enhanced osteoclastogenesis driven by the activation of FGFR2 signaling in bone marrow-derived macrophages. Consistently, Col1a1-Fgfr2S252W/+ mice, which had osteoblast-specific expression of Fgfr2 S252W, showed significant bone loss with a reduction of the bone length and excessive activity of osteoclasts was observed in the mutant mice. Taken together, the present study demonstrates that the imbalance in osteoblast and osteoclast coupling by abnormally increased Rankl expression in Fgfr2S252W/+ mutant osteoblasts is a major causative mechanism for bone loss and short long bones in Fgfr2S252W/+ mice.


Assuntos
Acrocefalossindactilia , Ligante RANK/metabolismo , Acrocefalossindactilia/genética , Acrocefalossindactilia/patologia , Animais , Diferenciação Celular , Técnicas de Introdução de Genes , Humanos , Camundongos , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Crânio/patologia
6.
Pediatr Allergy Immunol ; 33(2): e13724, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34936126

RESUMO

BACKGROUND: Gut microbiota dysbiosis is linked to the development and responses of the immune system and can play an important role in the onset of allergic diseases including atopic dermatitis (AD). This study investigated the association between host genetics and the gut microbiota in AD. METHODS: A global gene expression profiling of the gut epithelial colonocytes, genetic variations analysis, and the gut microbial composition analysis were performed. RESULTS: This study identified the upregulation of PTGR2 (p = .028), a gene involved in prostaglandin catalysis and inflammatory responses, as a potential risk factor for AD. In subsequent fine mapping analysis using 17 single nucleotide polymorphisms (SNPs) of PTGR2 in 864 Korean subjects (420 AD patients and 444 unaffected controls), several SNPs and haplotypes showed significant associations with AD and its SCORing AD (SCORAD) values (p = .002). To investigate host-microbial interactions, further gut microbiota data and genotypes were obtained from an independent cohort of 176 subjects (91 AD patients and 85 controls). From correlation analysis, a significantly negative association between SNP and Bifidobacterium abundance was observed in AD patients (p = .005). In additional observations of PTGR2-associated downstream molecules, NRF2 (p = .004) and several antioxidant genes (GSTT1, GCLC, GPX1; p < .05) showed significantly reduced expression in AD patients. CONCLUSIONS: Our current findings suggest that the interaction between PTGR2 dysregulated expression and a Bifidobacterium abundance affects a higher risk of AD and a more severe onset.


Assuntos
Dermatite Atópica , Microbioma Gastrointestinal , Bifidobacterium/genética , Criança , Dermatite Atópica/genética , Disbiose , Interações entre Hospedeiro e Microrganismos , Humanos , Polimorfismo de Nucleotídeo Único
7.
Allergy ; 74(4): 709-719, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30242844

RESUMO

BACKGROUND: Microbes in the airway have been shown to be associated with the pathogenesis of asthma. The upper airway microbiome influences the dysbiosis of the lower airway microbiome. However, to date, the influence of upper airway microbiome for adult and elderly asthma has not been fully elucidated. Here, the metagenome of upper airway microbiome of young adults and elderly was analyzed to identify their association with adult asthma. METHODS: Nasopharyngeal swabs were collected from young adult and elderly asthma patients and non-asthmatic subjects. The compositions and functional genes of airway microbiome were analyzed by high-throughput sequencing. RESULTS: The composition of microbiota differed between young adult and elderly, and it was different between asthmatics and non-asthmatics in each age group. Different bacteria were related to FEV1% predicted in each age group. Genes related to lysine degradation, N-glycan biosynthesis, caprolactam degradation, and PPAR signaling pathway, which could be related to the reduction in inflammation and degradation of air pollutants, were higher in non-asthmatics. Genes related to pentose phosphate pathway, lipopolysaccharide biosynthesis, flagella assembly, and bacterial chemotaxis-which may all be related to increased inflammation and colonization of pathogenic bacteria-were higher in young adult asthmatic patients. However, the functional genes of airway microbiome in elderly patients were not significantly different according to asthma morbidity. CONCLUSIONS: These results suggest that the composition and function of upper airway microbiome could influence asthma pathogenesis, and the microbiome could play various roles depending on the age group.


Assuntos
Asma/microbiologia , Microbiota/genética , Sistema Respiratório/microbiologia , Fatores Etários , Idoso , Bactérias/genética , Bactérias/isolamento & purificação , Feminino , Humanos , Masculino , Microbiota/imunologia , Doenças Nasofaríngeas/microbiologia , Adulto Jovem
8.
J Allergy Clin Immunol ; 141(4): 1310-1319, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29339259

RESUMO

BACKGROUND: Perturbations of the infant gut microbiota can shape development of the immune system and link to the risk of allergic diseases. OBJECTIVE: We sought to understand the role of the gut microbiome in patients with atopic dermatitis (AD). The metagenome of the infant gut microbiome was analyzed according to feeding types. METHODS: Composition of the gut microbiota was analyzed in fecal samples from 129 infants (6 months old) by using pyrosequencing, including 66 healthy infants and 63 infants with AD. The functional profile of the gut microbiome was analyzed by means of whole-metagenome sequencing (20 control subjects and 20 patients with AD). In addition, the total number of bacteria in the feces was determined by using real-time PCR. RESULTS: The gut microbiome of 6-month-old infants was different based on feeding types, and 2 microbiota groups (Bifidobacterium species-dominated and Escherichia/Veillonella species-dominated groups) were found in breast-fed and mixed-fed infants. Bacterial cell amounts in the feces were lower in infants with AD than in control infants. Although no specific taxa directly correlated with AD in 16S rRNA gene results, whole-metagenome analysis revealed differences in functional genes related to immune development. The reduction in genes for oxidative phosphorylation, phosphatidylinositol 3-kinase-Akt signaling, estrogen signaling, nucleotide-binding domain-like receptor signaling, and antigen processing and presentation induced by reduced colonization of mucin-degrading bacteria (Akkermansia muciniphila, Ruminococcus gnavus, and Lachnospiraceae bacterium 2_1_58FAA) was significantly associated with stunted immune development in the AD group compared with the control group (P < .05). CONCLUSIONS: Alterations in the gut microbiome can be associated with AD because of different bacterial genes that can modulate host immune cell function.


Assuntos
Aleitamento Materno , Dermatite Atópica/microbiologia , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/imunologia , Fórmulas Infantis/efeitos adversos , Estudos de Casos e Controles , DNA Bacteriano , Dermatite Atópica/imunologia , Fezes/microbiologia , Feminino , Humanos , Lactente , Masculino , Metagenoma , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
9.
J Cell Physiol ; 233(12): 9390-9403, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30132832

RESUMO

Myoblast fusion is critical for muscle growth, regeneration, and repair. We previously reported that the enzyme peptidyl-prolyl cis-trans isomerase NIMA interacting 1 (Pin1) is involved in osteoclast fusion. The objective of this study was to investigate the possibility that Pin1 also inhibits myoblast fusion. Here, we show the increased number of nuclei in the Pin1+/- mice muscle fiber compared to that in wild-type mice. Moreover, we show that low dose of the Pin1 inhibitor dipentamethylene thiuram monosulfide treatment caused enhanced fusion in C2C12 cells. The R-Smads are well-known mediators of muscle hypertrophy and hyperplasia as well as being substrates of Pin1. We found that Pin1 is crucial for maintaining the stability of Smad3 (homologues of the Drosophila protein, mothers against decapentaplegic (Mad) and the Caenorhabditis elegans protein Sma). Our results show that serine 204 within Smad3 is the key Pin1-binding site during inhibition of myoblast fusion and that both the transforming growth factor-ß receptor and extracellular signal-regulated kinase (ERK)-mediated phosphorylation are required for the interaction of Pin1 with Smad3. These findings suggest that a precise level of Pin1 activity is essential for regulating myoblast fusion during myogenesis and muscle regeneration.


Assuntos
Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Proteína Smad3/metabolismo , Animais , Fusão Celular , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos Endogâmicos C57BL , Atrofia Muscular/genética , Mioblastos/citologia , Mioblastos/metabolismo , Miostatina/metabolismo , Fosforilação , Ligação Proteica , Serina/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
10.
J Synchrotron Radiat ; 25(Pt 3): 878-884, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714200

RESUMO

A scanning transmission X-ray microscope is operational at the 10A beamline at the Pohang Light Source. The 10A beamline provides soft X-rays in the photon energy range 100-2000 eV using an elliptically polarized undulator. The practically usable photon energy range of the scanning transmission X-ray microscopy (STXM) setup is from ∼150 to ∼1600 eV. With a zone plate of 25 nm outermost zone width, the diffraction-limited space resolution, ∼30 nm, is achieved in the photon energy range up to ∼850 eV. In transmission mode for thin samples, STXM provides the element, chemical state and magnetic moment specific distributions, based on absorption spectroscopy. A soft X-ray fluorescence measurement setup has been implemented in order to provide the elemental distribution of thicker samples as well as chemical state information with a space resolution of ∼50 nm. A ptychography setup has been implemented in order to improve the space resolution down to 10 nm. Hardware setups and application activities of the STXM are presented.

12.
Nano Lett ; 17(11): 6997-7002, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-29064253

RESUMO

We report on the fabrication and electrical transport properties of superconducting junctions made of ß-Ag2Se topological insulator (TI) nanowires in contact with Al superconducting electrodes. The temperature dependence of the critical current indicates that the superconducting junction belongs to a short and diffusive junction regime. As a characteristic feature of the narrow junction, the critical current decreases monotonously with increasing magnetic field. The stochastic distribution of the switching current exhibits the macroscopic quantum tunneling behavior, which is robust up to T = 0.8 K. Our observations indicate that the TI nanowire-based Josephson junctions can be a promising building block for the development of nanohybrid superconducting quantum bits.

13.
Asian-Australas J Anim Sci ; 31(8): 1373-1380, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29381907

RESUMO

OBJECTIVE: This study was designed to investigate the effects of temperature and storage time on the evolution of bacterial communities in swine manure. METHODS: Manure was stored at -20°C, 4°C, 20°C, or 37°C and sampled at 7-day intervals over 28 days of storage, for a total of 5 time points. To assess the bacterial species present, 16S ribosomal RNA gene sequences were analyzed using pyrosequencing. RESULTS: After normalization, 113,934 sequence reads were obtained, with an average length of 466.6±4.4 bp. The diversity indices of the communities reduced as temperature and storage time increased, and the slopes of rarefaction curves decreased from the second week in samples stored at -20°C and 4°C. These results indicate that the richness of the bacterial community in the manure reduced as temperature and storage time increased. Firmicutes were the dominant phylum in all samples examined, ranging from 89.3% to 98.8% of total reads, followed by Actinobacteria, which accounted for 0.6% to 7.9%. A change in community composition was observed in samples stored at 37°C during the first 7 days, indicating that temperature plays an important role in determining the microbiota of swine manure. Clostridium, Turicibacter, Streptococcus, and Lactobacillus within Firmicutes, and Corynebacterium within Actinobacteria were the most dominant genera in fresh manure and all stored samples. CONCLUSION: Based on our findings, we propose Clostridium as an indicator genus of swine manure decomposition in an anaerobic environment. The proportions of dominant genera changed in samples stored at 20°C and 37°C during the fourth week. Based on these results, it was concluded that the microbial communities of swine manure change rapidly as storage time and temperature increase.

14.
J Cell Physiol ; 232(10): 2798-2805, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27800612

RESUMO

Pin1 is a peptidyl prolyl cis-trans isomerase that specifically binds to the phosphoserine-proline or phosphothreonine-proline motifs of several proteins. We reported that Pin1 plays a critical role in the fate determination of Smad1/5, Runx2, and ß-catenin that are indispensable nuclear proteins for osteoblast differentiation. Though several chemical inhibitors has been discovered for Pin1, no activator has been reported as of yet. In this study, we directly introduced recombinant Pin1 protein successfully into the cytoplasm via fibroin nanoparticle encapsulated in cationic lipid. This nanoparticle-lipid complex delivered its cargo with a high efficiency and a low cytotoxicity. Direct delivery of Pin1 leads to increased Runx2 and Smad signaling and resulted in recovery of the osteogenic marker genes expression and the deposition of mineral in Pin1-deficient cells. These result indicated that a direct Pin1 protein delivery method could be a potential therapeutics for the osteopenic diseases. J. Cell. Physiol. 232: 2798-2805, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Peptidilprolil Isomerase de Interação com NIMA/deficiência , Peptidilprolil Isomerase de Interação com NIMA/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Osteogênese/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Células 3T3 , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Portadores de Fármacos , Composição de Medicamentos , Fibroínas/química , Lipídeos/química , Masculino , Camundongos , Camundongos Knockout , Peptidilprolil Isomerase de Interação com NIMA/genética , Nanopartículas , Fenótipo , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Fatores de Tempo , beta Catenina/metabolismo
15.
Nanotechnology ; 28(12): 125603, 2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-28220763

RESUMO

We report the characterization and formation of sonication-assisted liquid phase exfoliation of bulk black phosphorus (BP) crystals with the incorporation of two representative ionic liquids (ILs) ([Emim][Tf2N] and [Bmim][Tf2N]) as green dispersing media was attempted, which resulted in stable dispersion of multi-layer BP flakes with unsuspected high oxidation resistance and chemical/structural integrity due to the presence of IL layer on top of BP flakes. There are two unveiled issues for the generation of BP dispersion in ILs. First, thin films of BP flakes can be simply prepared through our approach. Because self-oxidation of BP in ambient condition can be significantly minimized in ILs, vacuum filtration step can be adopted to produce BP thin films in ambient condition. Second, the binding of IL molecules on BP flakes has been firstly demonstrated by the time-of-flight secondary ion mass spectrometry characterization. In addition to the exploitation of ILs as the green solvents with less environmental harmfulness, IL-based exfoliation of BP might be easily scalable because harsh control of atmospheric oxygen and moisture is unnecessary in this approach.

16.
Angew Chem Int Ed Engl ; 56(50): 15998-16002, 2017 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-29071771

RESUMO

By greatly enhancing binding affinities against target biomolecules, multivalent interactions provide an attractive strategy for biosensing. However, there is also a major concern for increased binding to nonspecific targets by multivalent binding. A range of charge-engineered probes of a structure-specific RNA binding protein PAZ as well as multivalent forms of these PAZ probes were constructed by using diverse multivalent avidin proteins (2-mer, 4-mer, and 24-mer). Increased valency vastly enhanced the binding stability of PAZ to structured target RNA. Surprisingly, nonspecific RNA binding of multivalent PAZ can be reduced even below that of the PAZ monomer by controlling negative charges on both PAZ and multivalent avidin scaffolds. The optimized 24-meric PAZ showed nearly irreversible binding to target RNA with negligible binding to nonspecific RNA, and this ultra-specific 24-meric PAZ probe allowed SERS detection of intact microRNAs at an attomolar level.


Assuntos
Sondas Moleculares/química , Proteínas de Ligação a RNA/química , RNA/química , Sítios de Ligação , Modelos Moleculares , Análise Espectral Raman , Propriedades de Superfície
17.
Anal Chem ; 88(2): 1078-82, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26717968

RESUMO

A novel method (i.e., continuous magnetic cell separation in a microfluidic channel) is demonstrated to be capable of inducing multifractionation of mixed cell suspensions into multiple outlet fractions. Here, multicomponent cell separation is performed with three different distinguishable magnetic nanoclusters (MnFe2O4, Fe3O4, and CoFe2O4), which are tagged on A431 cells. Because of their mass magnetizations, which can be ideally altered by doping with magnetic atom compositions (Mn, Fe, and Co), the trajectories of cells with each magnetic nanocluster in a flow are shown to be distinct when dragged under the same external magnetic field; the rest of the magnetic characteristics of the nanoclusters are identically fixed. This proof of concept study, which utilizes the magnetization-controlled nanoclusters (NCs), suggests that precise and effective multifractionation is achievable with high-throughput and systematic accuracy for dynamic cell separation.


Assuntos
Separação Celular/instrumentação , Separação Celular/métodos , Nanopartículas de Magnetita/química , Técnicas Analíticas Microfluídicas , Elementos de Transição/química , Linhagem Celular Tumoral , Humanos , Fenômenos Magnéticos , Técnicas Analíticas Microfluídicas/instrumentação , Tamanho da Partícula , Propriedades de Superfície
20.
Helicobacter ; 21(6): 493-503, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26991862

RESUMO

BACKGROUND: Probiotic supplementation is utilized to alleviate the side effects associated with antibiotic therapy for Helicobacter pylori infection. Several studies have described the effects of administration of probiotics on the gut microbiota during antibiotic therapy. However, most of these studies have focused on specific bacteria, thereby providing limited information on the functional roles of the altered microbiota. Therefore, we examined the impact of probiotic supplementation on the structure and functional dynamics of the gut microbiota during H. pylori eradication, using whole-metagenomic sequence analysis. METHODS: Subjects were divided into two groups: the antibiotics group, which received only antibiotics, and the probiotics group, which received antibiotics with probiotic supplementation. The structural and functional profiles of gut microbiota was analyzed using metagenomic DNA extracted from the feces during treatment by Illumina MiSeq system. RESULTS: The overall alterations in microbiota, as revealed by whole metagenome sequencing, were similar with results from our previous 16S rRNA gene-based analysis. The proportional shift in functional gene families was greater in the antibiotics group than in the probiotics group. In particular, the proportion of genes related to selenocompound metabolism was reduced in the probiotics group, whereas genes associated with the metabolism of nucleotide sugars were increased. CONCLUSION: The functional alterations of gut microbiota may link to the reduction in intestinal irritation and maintenance of bacterial diversity observed following probiotic supplementation with antibiotic therapy. The potential beneficial roles of altered gut microbiota following probiotic supplementation are expected a reduction in side effects such as intestinal irritation and antibiotics resistance.


Assuntos
Antibacterianos/administração & dosagem , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Infecções por Helicobacter/terapia , Probióticos/administração & dosagem , Adulto , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA