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1.
Cell ; 165(5): 1280-1292, 2016 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-27203113

RESUMEN

The cistrome is the complete set of transcription factor (TF) binding sites (cis-elements) in an organism, while an epicistrome incorporates tissue-specific DNA chemical modifications and TF-specific chemical sensitivities into these binding profiles. Robust methods to construct comprehensive cistrome and epicistrome maps are critical for elucidating complex transcriptional networks that underlie growth, behavior, and disease. Here, we describe DNA affinity purification sequencing (DAP-seq), a high-throughput TF binding site discovery method that interrogates genomic DNA with in-vitro-expressed TFs. Using DAP-seq, we defined the Arabidopsis cistrome by resolving motifs and peaks for 529 TFs. Because genomic DNA used in DAP-seq retains 5-methylcytosines, we determined that >75% (248/327) of Arabidopsis TFs surveyed were methylation sensitive, a property that strongly impacts the epicistrome landscape. DAP-seq datasets also yielded insight into the biology and binding site architecture of numerous TFs, demonstrating the value of DAP-seq for cost-effective cistromic and epicistromic annotation in any organism.


Asunto(s)
Arabidopsis/genética , ADN de Plantas/genética , Genoma de Planta , Elementos de Respuesta , Análisis de Secuencia de ADN/métodos , Factores de Transcripción/metabolismo , Secuencias de Aminoácidos , ADN de Plantas/metabolismo , Epigénesis Genética , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/genética
3.
PLoS Genet ; 18(11): e1010473, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36413574

RESUMEN

Histone acetylation has been shown to involve in stress responses. However, the detailed molecular mechanisms that how histone deacetylases and transcription factors function in drought stress response remain to be understood. In this research, we show that ENAP1 and ENAP2 are positive regulators of drought tolerance in plants, and the enap1enap2 double mutant is more sensitive to drought stress. Both ENAP1 and ENAP2 interact with MYB44, a transcription factor that interacts with histone deacetylase HDT4. Genetics data show that myb44 null mutation enhances the sensitivity of enap1enap2 to drought stress. Whereas, HDT4 negatively regulates plant drought response, the hdt4 mutant represses enap1enap2myb44 drought sensitive phenotype. In the normal condition, ENAP1/2 and MYB44 counteract the HDT4 function for the regulation of H3K27ac. Upon drought stress, the accumulation of MYB44 and reduction of HDT4 leads to the enrichment of H3K27ac and the activation of target gene expression. Overall, this research provides a novel molecular mechanism by which ENAP1, ENAP2 and MYB44 form a complex to restrict the function of HDT4 in the normal condition; under drought condition, accumulated MYB44 and reduced HDT4 lead to the elevation of H3K27ac and the expression of drought responsive genes, as a result, plants are drought tolerant.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Sequías , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(11): e2112109119, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35263231

RESUMEN

SignificanceDirect ethanol fuel cells are attracting growing attention as portable power sources due to their advantages such as higher mass-energy density than hydrogen and less toxicity than methanol. However, it is challenging to achieve the complete electrooxidation to generate 12 electrons per ethanol, resulting in a low fuel utilization efficiency. This manuscript reports the complete ethanol electrooxidation by engineering efficient catalysts via single-atom modification. The combined electrochemical measurements, in situ characterization, and density functional theory calculations unravel synergistic effects of single Rh atoms and Pt nanocubes and identify reaction pathways leading to the selective C-C bond cleavage to oxidize ethanol to CO2. This study provides a unique single-atom approach to tune the activity and selectivity toward complicated electrocatalytic reactions.

5.
Proc Natl Acad Sci U S A ; 119(43): e2213373119, 2022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36256822

RESUMEN

The high level of reactive oxygen species (ROS) in the rheumatoid arthritis (RA) microenvironment (RAM) and its persistent inflammatory nature can promote damage to joints, bones, and the synovium. Targeting strategies that integrate effective RAM regulation with imaging-based monitoring could lead to improvements in the diagnosis and treatment of RA. Here, we report the combined use of small interfering RNAs (siRNAsT/I) and Prussian blue nanoparticles (PBNPs) to silence the expression of proinflammatory cytokines TNF-α/IL-6 and scavenge the ROS associated with RAM. To enhance the in vitro and in vivo biological stability, biocompatibility, and targeting capability of the siRNAsT/I and PBNPs, macrophage membrane vesicles were used to prepare biomimetic nanoparticles, M@P-siRNAsT/I. The resulting constructs were found to suppress tumor necrosis factor-α/interleukin-6 expression and overcome the hypoxic nature of RAM, thus alleviating RA-induced joint damage in a mouse model. The M@P-siRNAsT/I of this study could be monitored via near-infrared photoacoustic (PA) imaging. Moreover, multispectral PA imaging without the need for labeling permitted the real-time evaluation of M@P-siRNAsT/I as a putative RA treatment. Clinical microcomputed tomography and histological analysis confirmed the effectiveness of the treatment. We thus suggest that macrophage-biomimetic M@P-siRNAsT/I and their analogs assisted by PA imaging could provide a new strategy for RA diagnosis, treatment, and monitoring.


Asunto(s)
Artritis Reumatoide , Nanopartículas , Ratones , Animales , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6 , Especies Reactivas de Oxígeno/metabolismo , Biomimética , Microtomografía por Rayos X , Artritis Reumatoide/metabolismo , Citocinas/metabolismo , ARN Interferente Pequeño/uso terapéutico
6.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35193966

RESUMEN

Photoacoustic (PA) imaging offers promise for biomedical applications due to its ability to image deep within biological tissues while providing detailed molecular information; however, its detection sensitivity is limited by high background signals that arise from endogenous chromophores. Genetic reporter proteins with photoswitchable properties enable the removal of background signals through the subtraction of PA images for each light-absorbing form. Unfortunately, the application of photoswitchable chromoproteins for tumor-targeted imaging has been hampered by the lack of an effective targeted delivery scheme; that is, photoswitchable probes must be delivered in vivo with high targeting efficiency and specificity. To overcome this limitation, we have developed a tumor-targeting delivery system in which tumor-homing bacteria (Escherichia coli) are exploited as carriers to affect the point-specific delivery of genetically encoded photochromic probes to the tumor area. To improve the efficiency of the desired background suppression, we engineered a phytochrome-based reporter protein (mDrBphP-PCMm/F469W) that displays higher photoswitching contrast than those in the current state of the art. Photoacoustic computed tomography was applied to achieve good depth and resolution in the context of in vivo (mice) imaging. The present system effectively integrates a genetically encoded phytochrome-based reporter protein, PA imaging, and synthetic biology (GPS), to achieve essentially background-suppressed tumor-targeted PA monitoring in deep-seated tissues. The ability to image tumors at substantial depths may enable target-specific cancer diagnoses to be made with greater sensitivity, fidelity, and specificity.


Asunto(s)
Neoplasias/diagnóstico por imagen , Técnicas Fotoacústicas/métodos , Fitocromo/metabolismo , Animales , Línea Celular Tumoral , Escherichia coli , Femenino , Genes Reporteros/genética , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Imagen Molecular/métodos , Fitocromo/farmacología , Análisis Espectral/métodos , Tomografía Computarizada por Rayos X/métodos
7.
J Am Chem Soc ; 146(7): 4620-4631, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38330912

RESUMEN

Pancreatic cancer is highly lethal. New diagnostic and treatment modalities are desperately needed. We report here that an expanded porphyrin, cyclo[8]pyrrole (CP), with a high extinction coefficient (89.16 L/g·cm) within the second near-infrared window (NIR-II), may be formulated with an αvß3-specific targeting peptide, cyclic-Arg-Gly-Asp (cRGD), to form cRGD-CP nanoparticles (cRGD-CPNPs) with promising NIR-II photothermal (PT) therapeutic and photoacoustic (PA) imaging properties. Studies with a ring-array PA tomography system, coupled with analysis of control nanoparticles lacking a targeting element (CPNPs), revealed that cRGD conjugation promoted the delivery of the NPs through abnormal vessels around the tumor to the solid tumor core. This proved true in both subcutaneous and orthotopic pancreatic tumor mice models, as confirmed by immunofluorescent studies. In combination with NIR-II laser photoirradiation, the cRGD-CPNPs provided near-baseline tumor growth inhibition through PTT both in vitro and in vivo. Notably, the combination of the present cRGD-CPNPs and photoirradiation was found to inhibit intra-abdominal metastases in an orthotopic pancreatic tumor mouse model. The cRGD-CPNPs also displayed good biosafety profiles, as inferred from PA tomography, blood analyses, and H&E staining. They thus appear promising for use in combined PA imaging and PT therapeutic treatment of pancreatic cancer.


Asunto(s)
Nanopartículas , Neoplasias Pancreáticas , Técnicas Fotoacústicas , Animales , Ratones , Pirroles/uso terapéutico , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/terapia , Nanopartículas/química , Tomografía Computarizada por Rayos X , Técnicas Fotoacústicas/métodos , Línea Celular Tumoral , Fototerapia
8.
Cancer Sci ; 115(8): 2630-2645, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38889208

RESUMEN

Prostate carcinoma represents a predominant malignancy affecting the male population, with androgen deprivation therapy (ADT) serving as a critical therapeutic modality for advanced disease states, but it often leads to the development of resistance. Enzalutamide (Enz), a second-generation antiandrogen drug, initially offers substantial therapeutic benefit, but its efficacy wanes as drug resistance ensues. In this study, we found that synaptotagmin 4 (SYT4) is an upregulated gene in enzalutamide-resistant (EnzR) cell lines. The downregulation of SYT4, in combination with enzalutamide therapy, substantially enhances the antiproliferative effect on resistant prostate cancer cells beyond the capacity of enzalutamide monotherapy. SYT4 promotes vesicle efflux by binding to the synaptosome-associated protein 25 (SNAP25), thereby contributing to cell resistance against enzalutamide. The elevated expression of SYT4 is mediated by bromodomain-containing protein 4 (BRD4), and BRD4 inhibition effectively suppressed the expression of SYT4. Treatment with a therapeutic dose of enzalutamide combined with ASO-1, an antisense oligonucleotide drug targeting SYT4, shows promising results in reversing the resistance of prostate cancer to enzalutamide.


Asunto(s)
Benzamidas , Resistencia a Antineoplásicos , Exosomas , Nitrilos , Feniltiohidantoína , Neoplasias de la Próstata , Sinaptotagminas , Feniltiohidantoína/farmacología , Masculino , Humanos , Línea Celular Tumoral , Exosomas/metabolismo , Exosomas/efectos de los fármacos , Sinaptotagminas/metabolismo , Sinaptotagminas/genética , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Animales , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Ratones , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas que Contienen Bromodominio , Proteína 25 Asociada a Sinaptosomas
9.
Genome Res ; 31(4): 622-634, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33722936

RESUMEN

Heterosis or hybrid vigor is a common phenomenon in plants and animals; however, the molecular mechanisms underlying heterosis remain elusive, despite extensive studies on the phenomenon for more than a century. Here we constructed a large collection of F1 hybrids of Saccharomyces cerevisiae by spore-to-spore mating between homozygous wild strains of the species with different genetic distances and compared growth performance of the F1 hybrids with their parents. We found that heterosis was prevalent in the F1 hybrids at 40°C. A hump-shaped relationship between heterosis and parental genetic distance was observed. We then analyzed transcriptomes of selected heterotic and depressed F1 hybrids and their parents growing at 40°C and found that genes associated with one-carbon metabolism and related pathways were generally up-regulated in the heterotic F1 hybrids, leading to improved cellular redox homeostasis at high temperature. Consistently, genes related with DNA repair, stress responses, and ion homeostasis were generally down-regulated in the heterotic F1 hybrids. Furthermore, genes associated with protein quality control systems were also generally down-regulated in the heterotic F1 hybrids, suggesting a lower level of protein turnover and thus higher energy use efficiency in these strains. In contrast, the depressed F1 hybrids, which were limited in number and mostly shared a common aneuploid parental strain, showed a largely opposite gene expression pattern to the heterotic F1 hybrids. We provide new insights into molecular mechanisms underlying heterosis and thermotolerance of yeast and new clues for a better understanding of the molecular basis of heterosis in plants and animals.


Asunto(s)
Carbono/metabolismo , Homeostasis , Calor , Vigor Híbrido , Saccharomyces cerevisiae , Homeostasis/genética , Vigor Híbrido/genética , Hibridación Genética , Oxidación-Reducción , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulación hacia Arriba
10.
Small ; 20(30): e2311648, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38402429

RESUMEN

Ternary strategy with integration characteristics and adaptability is a simple and effective method for blooming of the performance of photovoltaic devices. Herein, a novel wideband gap polymer donor PBB2-Hs is synthesized as the guest component to optimize all-polymer solar cells (all-PSCs). High-energy photon absorption and long exciton lifetime of PBB2-Hs constitute efficient energy transfer. Good miscibility and cascade energy levels promote the formation of alloy-like structure between PBB2-Hs and host system. The dual working mechanisms greatly improve photon capture and charge transfer in active layers. Additionally, the introduction of PBB2-Hs also optimizes the ordered molecular stacking of acceptors and suppresses molecular peristalsis. Upon adding 15 wt% PBB2-Hs, the ternary all-PSC achieved a champion efficiency of 17.66%, and can still maintain 82% photostability (24 h) and 91% storage stability (1000 h) of the original PCE. Moreover, the strong molecular stacking and entanglement between PBB2-Hs and the host material increased the elongation at break of ternary blend film by 1.6 times (16.2%), allowing the flexible device to maintain 83% of the original efficiency after 800 bends (R = 5 mm). This work highlights the effectiveness of guest polymer on simultaneously improving photovoltaic performance, photostability and mechanical stability in all-PSCs.

11.
J Transl Med ; 22(1): 24, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38183115

RESUMEN

BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a rare disease, belonging to the same category of urothelial cancers as bladder cancer (BC). Despite sharing similar non-surgical treatment modalities, UTUC demonstrates a higher metastasis propensity than BC. Furthermore, although both cancers exhibit similar molecular disease emergence mechanisms, sequencing data reveals some differences. Our study investigates the transcriptomic distinctions between UTUC and BC, explores the causes behind UTUC's heightened metastatic tendency, constructs a model for UTUC metastasis and prognosis, and propose personalized treatment strategies for UTUC. METHODS: In our research, we utilized differential gene expression analysis, interaction networks, and Cox regression to explore the enhanced metastatic propensity of UTUC. We formulated and validated a prognostic risk model using diverse techniques, including cell co-culture, reverse transcription quantitative polymerase chain reaction (rt-qPCR), western blotting, and transwell experiments. Our methodological approach also involved survival analysis, risk model construction, and drug screening leveraging the databases of CTRPv2, PRISM and CMap. We used the Masson staining technique for histological assessments. All statistical evaluations were conducted using R software and GraphPad Prism 9, reinforcing the rigorous and comprehensive nature of our research approach. RESULTS: Screening through inflammatory fibrosis revealed a reduction of extracellular matrix and cell adhesion molecules regulated by proteoglycans in UTUC compared with BC, making UTUC more metastasis-prone. We demonstrated that SDC1, LUM, VEGFA, WNT7B, and TIMP3, are critical in promoting UTUC metastasis. A risk model based on these five molecules can effectively predict the risk of UTUC metastasis and disease-free survival time. Given UTUC's unique molecular mechanisms distinct from BC, we discovered that UTUC patients could better mitigate the issue of poor prognosis associated with UTUC's easy metastasis through tyrosine kinase inhibitors (TKIs) alongside the conventional gemcitabine and cisplatin chemotherapy regimen. CONCLUSIONS: The poor prognosis of UTUC because of its high metastatic propensity is intimately tied to inflammatory fibrosis induced by the accumulation of reactive oxygen species. The biological model constructed using the five molecules SDC1, LUM, VEGFA, WNT7B, and TIMP3 can effectively predict patient prognosis. UTUC patients require specialized treatments in addition to conventional regimens, with TKIs exhibiting significant potential.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/terapia , Medicina de Precisión , Perfilación de la Expresión Génica , Transcriptoma/genética
12.
Opt Express ; 32(10): 18150-18160, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858978

RESUMEN

Perineuronal nets (PNNs) are important functional structures on the surface of nerve cells. Observation of PNNs usually requires dyeing or fluorescent labeling. As a network structure with a micron grid and sub-wavelength thickness but no special optical properties, quantitative phase imaging (QPI) is the only purely optical method for high-resolution imaging of PNNs. We proposed a Scattering Quantitative Interference Imaging (SQII) method which measures the geometric rather than transmission or reflection phase during the scattering process to visualize PNNs. Different from QIP methods, SQII method is sensitive to scattering and not affected by wavelength changes. Via geometric phase shifting method, we simplify the phase shift operation. The SQII method not only focuses on interference phase, but also on the interference contrast. The singularity points and phase lines of the scattering geometric phase depict the edges of the network structure and can be found at the valley area of the interference contrast parameter SINDR under different wavelengths. Our SQII method has its unique imaging properties, is very simple and easy to implement and has more worth for promotion.

13.
Microb Pathog ; 195: 106907, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39218375

RESUMEN

Streptococcus agalactiae (S. agalactiae) is an opportunistic pathogen, and to date, studies have mainly focused on S. agalactiae strains isolated from humans, dairy cows, and fish. We reported one S. agalactiae strain, named CFFB, which was isolated from a healthy Sichuan golden snub-nosed monkey. Classical bacteriological approaches, as well as, next-generation sequencing, comparative genomics, and mice challenge test were used to characterize this strain. CFFB was identified as serotype III, ST19 combination which is a common type found in human strains. Phylogenetic analysis showed that the genome of CFFB was closely related to human clinical isolates, rather far away from animal strains. In total, CFFB contained fewer virulence-associated genes and antibiotic resistance genes than human isolates that were close to CFFB in evolutionary relationships. In the mice challenge test, CFFB had a relative weak virulence that just caused death in 33 % of ICR mice at a dose of 108 CFU by intraperitoneal injection, and CFFB was reisolated from the cardiac blood of the dead mice. Meanwhile, two intact prophages (prophage 1 and 2) were identified in the CFFB genome and shared high similarities with phage Javan52 and Javan29 which from human S. agalactiae isolate Gottschalk 1002A and RBH03, respectively. Moreover, the type II-A CRISPR-Cas system was detected in the CFFB genome, and the spacers from CFFB were the same to the streptococci isolates from human. These results suggest that CFFB isolated from healthy Sichuan golden snub-nosed monkeys may have its origin in human S. agalactiae. Our results suggested some genomic similarities between the S. agalactiae colonized in Sichuan golden snub-nosed monkey and those in infected humans.


Asunto(s)
Genoma Bacteriano , Filogenia , Infecciones Estreptocócicas , Streptococcus agalactiae , Animales , Streptococcus agalactiae/genética , Streptococcus agalactiae/aislamiento & purificación , Streptococcus agalactiae/patogenicidad , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/veterinaria , China , Virulencia/genética , Ratones , Colobinae/microbiología , Humanos , Profagos/genética , Ratones Endogámicos ICR , Factores de Virulencia/genética , Serogrupo , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades de los Monos/microbiología
14.
Glob Chang Biol ; 30(4): e17274, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38605677

RESUMEN

Climate change and other anthropogenic disturbances are increasing liana abundance and biomass in many tropical and subtropical forests. While the effects of living lianas on species diversity, ecosystem carbon, and nutrient dynamics are receiving increasing attention, the role of dead lianas in forest ecosystems has been little studied and is poorly understood. Trees and lianas coexist as the major woody components of forests worldwide, but they have very different ecological strategies, with lianas relying on trees for mechanical support. Consequently, trees and lianas have evolved highly divergent stem, leaf, and root traits. Here we show that this trait divergence is likely to persist after death, into the afterlives of these organs, leading to divergent effects on forest biogeochemistry. We introduce a conceptual framework combining horizontal, vertical, and time dimensions for the effects of liana proliferation and liana tissue decomposition on ecosystem carbon and nutrient cycling. We propose a series of empirical studies comparing traits between lianas and trees to answer questions concerning the influence of trait afterlives on the decomposability of liana and tree organs. Such studies will increase our understanding of the contribution of lianas to terrestrial biogeochemical cycling, and help predict the effects of their increasing abundance.


Asunto(s)
Ecosistema , Clima Tropical , Bosques , Árboles , Carbono
15.
Inorg Chem ; 63(36): 16733-16739, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39185620

RESUMEN

Sulfur hexafluoride (SF6) is widely used as an insulating gas, being an etchant and contrast agent in the electrical, semiconductor, and medical industries. However, due to its long lifetime and high global warming potential in the atmosphere, SF6 must be carefully handled to prevent leakage during production and usage. Herein, we report a sod-net metal-azolate framework (MAF) named MAF-stu-111, which decorates methyl and aldehyde groups in the porous windows, showing high adsorption affinity for SF6 at low pressure. Stability tests, gas adsorption, and breakthrough experiments demonstrated that MAF-stu-111 possesses excellent water and chemical stability, fully reversible SF6 uptake, high SF6/N2 separation selectivity (10:90, 285.2), good reusability, and high SF6 recovery purity (99.03%). Theoretical calculations revealed that hydrogen atoms of methyl and aldehyde groups can form multiple hydrogen bonds with SF6 molecules, which ensure that SF6 molecules are firmly held within the MAF-stu-111 framework, playing a key role in the selective separation of SF6/N2.

16.
Inorg Chem ; 63(9): 4185-4195, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38364251

RESUMEN

Posttreatment of pristine metal-organic frameworks (MOFs) with suitable vapor may be an effective way to regulate their structures and properties but has been less explored. Herein, we report an interesting example in which a crystalline nonporous Eu(III)-MOF was transferred to a porous amorphous MOF (aMOF) via iodine vapor adsorption-desorption posttreatment, and the resulting aMOF showed improved turn-on sensing properties with respect to Ag+ ions. The crystalline Eu-MOF, namely, Eu-IPDA, was assembled from Eu(III) and 4,4'-{4-[4-(1H-imidazol-1-yl)phenyl]pyridine-2,6-diyl}dibenzoic acid (H2IPDA) and exhibited a two-dimensional (2D) coordination network based on one-dimensional secondary building blocks. The close packing of the 2D networks gives rise to a three-dimensional supramolecular framework without any significant pores. Interestingly, the nonporous Eu-IPDA could absorb iodine molecules when Eu-IPDA crystals were placed in iodine vapor at 85 °C, and the adsorption capacity was 1.90 g/g, which is comparable to those of many MOFs with large BET surfaces. The adsorption of iodine is attributed to the strong interactions among the iodine molecule, the carboxy group, and the N-containing group and leads to the amorphization of the framework. After immersion of the iodine-loaded Eu-IPDA in EtOH, approximately 89.7% of the iodine was removed, resulting in a porous amorphous MOF, denoted as a-Eu-IPDA. In addition, the remaining iodine in the a-Eu-IPDA framework causes strong luminescent quenching in the fluorescence emission region of the Eu(III) center when compared with that in Eu-IPDA. The luminescence intensity of a-Eu-IPDA in water suspensions was significantly enhanced when Ag+ ions were added, with a detection limit of 4.76 × 10-6 M, which is 1000 times that of pristine Eu-IPDA. It also showed strong anti-interference ability over many common competitive metal ions and has the potential to sense Ag+ in natural water bodies and traditional Chinese medicine preparations. A mechanistic study showed that the interactions between Ag+ and the absorbed iodine, the carboxylate group, and the N atoms all contribute to the sensing performance of a-Eu-IPDA.

17.
Food Microbiol ; 123: 104566, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39038883

RESUMEN

Daqu is used as the fermentation starter of Baijiu and contributes diversified functional microbes for saccharifying grains and converting sugars into ethanol and aroma components in Baijiu products. Daqu is mainly classified into three types, namely low (LTD), medium (MTD) and high (HTD) temperature Daqu, according to the highest temperatures reached in their fermentation processes. In this study, we used the PacBio small-molecule real-time (SMRT) sequencing technology to determine the full-length 16 S rRNA gene sequences from the metagenomes of 296 samples of different types of Daqu collected from ten provinces in China, and revealed the bacterial diversity at the species level in the Daqu samples. We totally identified 310 bacteria species, including 78 highly abundant species (with a relative abundance >0.1% each) which accounted for 91.90% of the reads from all the Daqu samples. We also recognized the differentially enriched bacterial species in different types of Daqu, and in the Daqu samples with the same type but from different provinces. Specifically, Lactobacillales, Enterobacterales and Bacillaceae were significantly enriched in the LTD, MTD and HTD groups, respectively. The potential co-existence and exclusion relationships among the bacteria species involved in all the Daqu samples and in the LTD, MTD and HTD samples from a specific region were also identified. These results provide a better understanding of the bacterial diversity in different types of Daqu at the species level.


Asunto(s)
Bacterias , Fermentación , ARN Ribosómico 16S , ARN Ribosómico 16S/genética , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/metabolismo , China , Microbiota , Filogenia , ADN Bacteriano/genética , Biodiversidad , Bebidas Alcohólicas/microbiología , Bebidas Alcohólicas/análisis , Microbiología de Alimentos , Metagenoma , Alimentos Fermentados/microbiología
18.
J Sci Food Agric ; 104(3): 1668-1678, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37847204

RESUMEN

BACKGROUND: Hemp protein isolates (HPIs), which provide a well-balanced profile of essential amino acids comparable to other high-quality proteins, have recently garnered significant attention. However, the underutilized functional attributes of HPIs have constrained their potential commercial applications within the food and agriculture field. This study advocates the utilization of dynamic-high-pressure-microfluidization (DHPM) for the production of stable high-internal-phase emulsions (HIPEs), offering an efficient approach to fully exploit the potential of HPI resources. RESULTS: The findings underscore the effectiveness of DHPM in producing HPI as a stabilizing agent for HIPEs with augmented antioxidant activity. Microfluidized HPI exhibited consistent adsorption and anchoring at the oil-water interface, resulting in the formation of a dense and compact layer. Concurrently, the compression of droplets within HIPEs gave rise to a polyhedral framework, conferring viscoelastic properties and a quasi-solid behavior to the emulsion. Remarkably, HIPEs stabilized by microfluidized HPI demonstrated superior oxidative and storage stability, attributable to the establishment of an antioxidative barrier by microfluidized HPI particles. CONCLUSION: This study presents an appealing approach for transforming liquid oils into solid-like fats using HPI particles, all without the need for surfactants. HIPEs stabilized by microfluidized HPI particles hold promise as emerging food ingredients for the development of emulsion-based formulations with enhanced oxidative stability, thereby finding application in the food and agricultural industries. © 2023 Society of Chemical Industry.


Asunto(s)
Cannabis , Emulsiones/química , Excipientes , Oxidación-Reducción , Antioxidantes/metabolismo , Estrés Oxidativo , Tamaño de la Partícula
19.
BMC Oral Health ; 24(1): 105, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233815

RESUMEN

BACKGROUND: Peri-implantitis is a polybacterial infection that can lead to the failure of dental implant rehabilitation. This study aimed to profile the microbiome of the peri-implant plaque and estimate the effect of periodontitis on it among 40 Chinese participants with dental implant prostheses and presenting with varying peri-implant and periodontal health states. METHODS: Submucosal plaque samples were collected from four distinct clinical categories based on both their implant and periodontal health status at sampling point. Clinical examinations of dental implant and remaining teeth were carried out. Metagenomic analysis was then performed. RESULTS: The microbiome of the peri-implantitis sites differed from that of healthy implant sites, both taxonomically and functionally. Moreover, the predominant species in peri-implantitis sites were slightly affected by the presence of periodontitis. T. forsythia, P. gingivalis, T. denticola, and P. endodontalis were consistently associated with peri-implantitis and inflammatory clinical parameters regardless of the presence of periodontitis. Prevotella spp. and P. endodontalis showed significant differences in the peri-implantitis cohorts under different periodontal conditions. The most distinguishing function between diseased and healthy implants is related to flagellar assembly, which plays an important role in epithelial cell invasion. CONCLUSIONS: The composition of the peri-implant microbiome varied in the diseased and healthy states of implants and is affected by individual periodontal conditions. Based on their correlations with clinical parameters, certain species are associated with disease and healthy implants. Flagellar assembly may play a vital role in the process of peri-implantitis.


Asunto(s)
Implantes Dentales , Placa Dental , Microbiota , Periimplantitis , Enfermedades Periodontales , Periodontitis , Humanos , Periimplantitis/microbiología , Implantes Dentales/microbiología , Estudios Transversales , Placa Dental/microbiología
20.
Small ; 19(50): e2304808, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37501314

RESUMEN

The synthesis of efficient and highly selective catalysts and rational reactor design play decisive roles in the industrial application of the electrocatalytic carbon dioxide reduction reaction (CO2 RR). In this study, a dual-metal-organic framework (MOF) copper-based catalytic electrode is designed and prepared in one step by in situ synthesis on a foamed copper substrate. The MOF-on-MOF structure can effectively inhibit the generation of H2 and CO, and further enhance the selectivity of HCOOH. Furthermore, by using cheap and durable poly(tetrafluoroethylene) (PTFE) instead of an expensive and fragile GDE, the optimized reactor design improves the stability and durability of the gas channel and the replaceability of the electrode. The structure-optimized reactor has a maximum Faradaic efficiency of 89.2% in neutral medium, and an average current density of 26.1 mA cm-2 in the flow cell, which has comparable performance to a GDE and can continue to operate stably. The use of PTFE improves the service life of the gas mass transfer channel, and the independent catalytic electrode can provide good catalytic efficiency. These results provide new insights into the reaction mechanism of structurally recombined double MOFs and PTFE-optimized CO2 RR reactor designs, providing technical support for the practical industrial application of the CO2 RR.

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