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1.
Antioxidants (Basel) ; 13(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38539899

RESUMO

This study investigated the effects of dietary chitosan oligosaccharide (COS) supplementation on meat quality, antioxidant capacity, and muscle fiber characteristics in the thigh muscle of broilers. The results showed that dietary COS supplementation decreased shear force and increased crude protein content and nutritional value in the thigh muscle, while decreasing the content of C16:0, C18:0, and total saturated fatty acids. Dietary COS supplementation increased free radical scavenging activity, antioxidant enzyme activity, and antioxidant enzyme-related gene expression. Additionally, COS promoted MyHCI while decreasing MyHCIIb mRNA expression levels. The myofiber transformation was associated with upregulated gene expression of CaN, NFATc1, MyoD, and SIRT1. Together, the results of this study demonstrate that dietary COS supplementation improves meat quality, nutritional value, antioxidant capacity, and myofiber transformation to more oxidative muscle fibers in the thigh muscle of broilers when its supplemental level is 400 mg/kg.

2.
Poult Sci ; 103(2): 103381, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157786

RESUMO

This study was conducted to investigate the effects of chitosan oligosaccharide (COS) supplementation on intestinal development and functions, inflammatory response, antioxidant capacity and the related signaling pathways in broilers aged d 1 to 14. A total of 240 one-day old male Arbor Acres broilers (40.47 ± 0.30 g) were randomly allotted to 4 groups, and each group consisted of 6 replicate pens with 10 broilers per replicate. Broilers fed a basal diet supplementation with COS at 0 (CON group), 200 (COS200 group), 400 (COS400 group), and 800 mg/kg (COS800 group) for 14 d, respectively. Broilers in the COS supplementation groups had no significant effects on growth performance. Compared to the CON group, dietary COS supplementation increased (P < 0.05) the relative weight of duodenum, jejunal lipase activity, duodenal and ileal villus surface area, and lower (P < 0.05) ileal amylase and alkaline phosphatase activity, and crypt depth. The expression level of duodenal glucose transporter 1 (GLUT1), Na+-glucose cotransporter 1 (SGLT1), peptide transporter 1 (PepT1), occludin, zonula occludens-1 (ZO-1), toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and interleukin-10 (IL-10), jejunal SGLT1, PepT1, occludin, tumor necrosis factor-α (TNF-α), and ileal SGLT1, PepT1, and fatty acid binding protein 1 (FABP1) was upregulated by COS. However, the expression level of duodenal FABP1 and TNF-α, jejunal GLUT1, ZO-1, TLR4, MyD88, nuclear factor kappa-B p65 (NF-κB p65), and IL-1ß, and ileal GLUT1, NF-κB p65, and IL-1ß was downregulated by COS. Furthermore, dietary COS supplementation increased duodenal catalase (CAT), glutathione peroxidase (GSH-Px), and total superoxide dismutase (T-SOD) activity, jejunal CAT and T-SOD activity, upregulated the expression level of duodenal nuclear factor-erythroid 2-related factor 2 (Nrf2), CAT, glutathione peroxidase 1 (GPX1), and copper and zinc superoxide dismutase (Cu/Zn SOD), jejunal CAT, and ileal Nrf2, CAT, and GPX1. These results suggested that COS could promote intestinal development and functions in broilers aged d 1 to 14, which might be mediated by alleviating intestinal inflammatory response and enhancing antioxidant capacity.


Assuntos
Antioxidantes , Quitosana , Masculino , Animais , Antioxidantes/metabolismo , Quitosana/farmacologia , Quitosana/metabolismo , Galinhas/fisiologia , Receptor 4 Toll-Like/metabolismo , Suplementos Nutricionais , Ocludina/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa , Transportador de Glucose Tipo 1 , Fator 88 de Diferenciação Mieloide , Fator 2 Relacionado a NF-E2/metabolismo , Dieta , Oligossacarídeos/farmacologia , Superóxido Dismutase/metabolismo , Ração Animal/análise
3.
Chem Commun (Camb) ; 59(98): 14583-14586, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37990871

RESUMO

Recently, production of hydrogen (H2) through the urea oxidation reaction (UOR) and hydrogen evolution reaction (HER) has acquired great attention because it is more environmentally friendly and energy-saving. Herein, an approach of water activation was developed for in situ growth of NiMo LDH nanosheet arrays on NiMo foam without using any binder or pressurizing or heating steps. The obtained NiMo foam electrodes showed exceptional catalytic activity and durability for both the UOR and HER. This work offers a new standpoint on designing electrodes with high activation for efficient and sustainable hydrogen production coupled with urea organic oxidation.

4.
Chem Commun (Camb) ; 59(75): 11212-11215, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37655438

RESUMO

In this paper, a facile and ultrafast two-step dipping process was developed to in situ form an electrocatalyst on a NiMo foam substrate without consuming extra energy. The obtained electrode showed a porous coral-like structure decorated with nanosheets and exhibited excellent overall water splitting properties in alkaline solution. This study provides a feasible strategy for developing an environmentally friendly and energy-efficient non-noble metal electrode for hydrogen production from water splitting.

5.
Front Vet Sci ; 10: 1208538, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601754

RESUMO

Trichinella spiralis (T. spiralis) muscle-larva excretory/secretory products (ML-ESPs) is a complex array of proteins with antitumor activity. We previously demonstrated that ML-ESPs inhibit the proliferation of A549 non-small cell lung cancer (NSCLC) cell line. However, the mechanism of ML-ESPs against A549 cells, especially on the transcriptional level, remains unknow. In this study, we systematically investigated a global profile bioinformatics analysis of transcriptional response of A549 cells treated with ML-ESPs. And then, we further explored the transcriptional regulation of genes related to glucose metabolism in A549 cells by ML-ESPs. The results showed that ML-ESPs altered the expression of 2,860 genes (1,634 upregulated and 1,226 downregulated). GO and KEGG analysis demonstrated that differentially expressed genes (DEGs) were mainly associated with pathway in cancer and metabolic process. The downregulated genes interaction network of metabolic process is mainly associated with glucose metabolism. Furthermore, the expression of phosphofructokinase muscle (PFKM), phosphofructokinase liver (PFKL), enolase 2 (ENO2), lactate dehydrogenase B (LDHB), 6-phosphogluconolactonase (6PGL), ribulose-phosphate-3-epimerase (PRE), transketolase (TKT), transaldolase 1 (TALDO1), which genes mainly regulate glycolysis and pentose phosphate pathway (PPP), were suppressed by ML-ESPs. Interestingly, tricarboxylic acid cycle (TCA)-related genes, such as pyruvate dehydrogenase phosphatase 1 (PDP1), PDP2, aconitate hydratase 1 (ACO1) and oxoglutarate dehydrogenase (OGDH) were upregulated by ML-ESPs. In summary, the transcriptome profiling of A549 cells were significantly altered by ML-ESPs. And we also provide new insight into how ML-ESPs induced a transcriptional reprogramming of glucose metabolism-related genes in A549 cells.

6.
Chemosphere ; 338: 139494, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37451640

RESUMO

Since the discovery of microemulsions, they have attracted great attention due to its unique properties, such as ultra-low interfacial tension and nanoscale droplets. During the past several decades, microemulsions have shown unparalleled advantages in critical metal separation and recovery, e.g., high separation rate, high recovery efficiency, and good selectivity. Therefore, fundamental understandings of such metal recovery behavior are of great significance for the continuous development of microemulsion-based separation technology in this field. Herein, we first systematically reviewed the application of regular microemulsion in the separation and recovery process of critical metals focusing on their separation mechanisms. Then, we summarized the recent progress of CO2-responsive microemulsions and highlighted their potential application in critical metal separation and recovery, aiming to provide some insights into alleviating the difficulties in demulsification during the stripping stage using regular microemulsions. In this section, the latest development of CO2-responsive microemulsions is introduced, and the relationship between their composition, microstructure and macroscopic properties is discussed. Discussion and future perspectives are provided highlighting the design of new microemulsions and potential application of CO2-responsive microemulsions for metal separation and recovery in the future.


Assuntos
Dióxido de Carbono , Dióxido de Carbono/química , Emulsões/química
7.
Anal Methods ; 15(17): 2105-2113, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37066613

RESUMO

The spread of the monkeypox virus (MPXV) from Central and West Africa to previously non-endemic regions has caused a global panic. In this context, the rapid, specific, and ultrasensitive detection of MPXV is crucial to contain its spread, though such technology has seldom been reported. Herein, we proposed an MPXV assay combining recombinase-aided amplification (RAA) and CRISPR/Cas12a. This assay targeted the highly conserved MPXV F3L gene and demonstrates a low detection limit (LOD) of 101 copies per µL. By leveraging the high specificity nature of RAA and CRISPR/Cas12a, we rationally optimized probes and conditions to achieve high selectivity that differentiates MPXV from other orthopox viruses and current high-profile viruses. To facilitate on-site screening of potential MPXV carriers, a kit integrating lateral flow strips was developed, enabling naked-eye MPXV detection with a LOD of 104 copies per µL. Our RAA-Cas12a-MPXV assay was able to detect MPXV without the need for sophisticated operation and expensive equipment. We believe that this assay can be rapidly deployed in emerging viral outbreaks for on-site surveillance of MPXV.


Assuntos
Monkeypox virus , Humanos , Monkeypox virus/genética , /genética , Sistemas CRISPR-Cas/genética , Recombinases/genética , África Ocidental
8.
Sci Rep ; 12(1): 6349, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428800

RESUMO

The development of 3D printing has recently attracted significant attention on constructing complex three-dimensional physiological microenvironments. However, it is very challenging to provide a bio-ink with cell-harmless and high mold accuracy during extrusion in 3D printing. To overcome this issue, a technique improving the shear-thinning performance of semi-IPN bio-ink, which is universally applicable to all alginate/gelatin-based materials, was developed. Semi-IPN bio-ink prepared by cyclic heating-cooling treatment in this study can reduce the cell damage without sacrificing the accuracy of the scaffolds for its excellent shear-thinning performance. A more than 15% increase in post-printing Cell viability verified the feasibility of the strategy. Moreover, the bio-ink with low molecular weight and wide molecular weight distribution also promoted a uniform cell distribution and cell proliferation in clusters. Overall, this strategy revealed the effects of molecular parameters of semi-IPN bio-inks on printing performance, and the cell activity was studied and it could be widely applicable to construct the simulated extracellular matrix with various bio-inks.


Assuntos
Bioimpressão , Bioimpressão/métodos , Matriz Extracelular , Hidrogéis/farmacologia , Tinta , Peso Molecular , Impressão Tridimensional , Engenharia Tecidual/métodos , Alicerces Teciduais
9.
Angew Chem Int Ed Engl ; 61(16): e202117480, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35112449

RESUMO

An enantioselective synthesis of (-)-10-hydroxyacutuminine is reported. Central to our strategy is a photochemical [2+2] cycloaddition that forges two of the quaternary stereocenters present in the acutumine alkaloids. A subsequent retro-aldol/Dieckmann sequence furnishes the spirocyclic cyclopentenone. Efforts to chlorinate the acutumine scaffold at C10 under heterolytic or radical deoxychlorination conditions led to the synthesis of an unexpected cyclopropane-containing pentacycle.


Assuntos
Ciclização , Reação de Cicloadição , Estereoisomerismo
10.
IEEE Trans Vis Comput Graph ; 27(2): 1709-1719, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33052861

RESUMO

Numerous sampling strategies have been proposed to simplify large-scale networks for highly readable visualizations. It is of great challenge to preserve contextual structures formed by nodes and edges with tight relationships in a sampled graph, because they are easily overlooked during the process of sampling due to their irregular distribution and immunity to scale. In this paper, a new graph sampling method is proposed oriented to the preservation of contextual structures. We first utilize a graph representation learning (GRL) model to transform nodes into vectors so that the contextual structures in a network can be effectively extracted and organized. Then, we propose a multi-objective blue noise sampling model to select a subset of nodes in the vectorized space to preserve contextual structures with the retention of relative data and cluster densities in addition to those features of significance, such as bridging nodes and graph connections. We also design a set of visual interfaces enabling users to interactively conduct context-aware sampling, visually compare results with various sampling strategies, and deeply explore large networks. Case studies and quantitative comparisons based on real-world datasets have demonstrated the effectiveness of our method in the abstraction and exploration of large networks.

11.
Bioact Mater ; 6(5): 1402-1412, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33210032

RESUMO

As photocrosslinkable materials, methacryloyl-modified hydrogels are widely used as bioinks in tissue engineering. Existing printing methods to use these hydrogels, including changing the viscosity of the material or mixing them with other printing components, have been explored, but their application has been limited due to low printing quality or high cost. In addition, the complex operation of bulky equipment restricts the application of these existing printing methods. This study presents a lightweight stereolithography-based three-dimensional (3D) bioprinting system with a smart mechanical and structural design. The developed bioprinter dimensions were 300 mm × 300 mm × 200 mm and it can be placed on a benchtop. The equipment has a mini bioink chamber to store a small amount of bioink for each printing. We systematically investigated the point-by-point curing process in the 3D bioprinting method, which can print mixed cells accurately and have good biocompatibility. Here, we provide a compact, low-cost stereolithography bioprinting system with excellent biocompatibility for 3D bioprinting with methacryloyl-modified hydrogels. It can be potentially used for drug screening, studying pathological mechanisms, and constructing biological disease models.

12.
NAR Genom Bioinform ; 2(4): lqaa084, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33575629

RESUMO

The current challenge in cancer research is to increase the resolution of driver prediction from gene-level to mutation-level, which is more closely aligned with the goal of precision cancer medicine. Improved methods to distinguish drivers from passengers are urgently needed to dig out driver mutations from increasing exome sequencing studies. Here, we developed an ensemble method, AI-Driver (AI-based driver classifier, https://github.com/hatchetProject/AI-Driver), to predict the driver status of somatic missense mutations based on 23 pathogenicity features. AI-Driver has the best overall performance compared with any individual tool and two cancer-specific driver predicting methods. We demonstrate the superior and stable performance of our model using four independent benchmarks. We provide pre-computed AI-Driver scores for all possible human missense variants (http://aidriver.maolab.org/) to identify driver mutations in the sea of somatic mutations discovered by personal cancer sequencing. We believe that AI-Driver together with pre-computed database will play vital important roles in the human cancer studies, such as identification of driver mutation in personal cancer genomes, discovery of targeting sites for cancer therapeutic treatments and prediction of tumor biomarkers for early diagnosis by liquid biopsy.

13.
Appl Opt ; 58(4): 1093-1100, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874163

RESUMO

Being susceptible to the change of atmospheric conditions, the volume emission rate (VER) is very suitable to be used as a light source by passive remote sensing for measuring atmospheric wind and temperature. Thus, the VERs emitted from O2(0-1) and O(S1) of the nightglow at 80-120 km are studied in this paper. Based on the Naval Research Laboratory Mass Spectrometer Incoherent Scatter (NRLMSISE-00) model data and the ground-based airglow imaging interferometer (GBAII) instrument observation for a local time and place, simulated VER profiles represented by four layers are obtained for the nightglow of O2(0-1) and O(S1). The O2(0-1) nightglow model peak values at 94 km on 6 December 2013 and 8 November 2011 are 8111 photons·cm-3·s-1 and 8406 photons·cm-3·s-1, respectively; however, the O(S1) VER peak at a higher altitude of about 96 km on 18 December 2011 is only 338 photons·cm-3·s-1. The upper atmospheric VER values have been derived to transfer into the ground-based detected column intensities by our GBAII prototype. The calculated column integrated emission rates (IERs) of O2(0-1) for 0° and 45° zenith angles are 1.48×107 and 1.91×107 photons·cm-2·s-1, respectively; the calculated column IERs of O(S1) are 5.53×105 and 7.03×105 photons·cm-2·s-1, respectively. Correspondingly, the detected column IERs obtained by GBAII are 2.43×107 for O2(0-1) and 6.57×105 photons·cm-2·s-1 for O(S1).

14.
Small ; 15(4): e1804216, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30569632

RESUMO

Low-concentration gelatin methacryloyl (GelMA) has excellent biocompatibility to cell-laden structures. However, it is still a big challenge to stably fabricate organoids (even microdroplets) using this material due to its extremely low viscosity. Here, a promising electro-assisted bioprinting method is developed, which can print low-concentration pure GelMA microdroplets with low cost, low cell damage, and high efficiency. With the help of electrostatic attraction, uniform GelMA microdroplets measuring about 100 µm are rapidly printed. Due to the application of lower external forces to separate the droplets, cell damage during printing is negligible, which often happens in piezoelectric or thermal inkjet bioprinting. Different printing states and effects of printing parameters (voltages, gas pressure, nozzle size, etc.) on microdroplet diameter are also investigated. The fundamental properties of low-concentration GelMA microspheres are subsequently studied. The results show that the printed microspheres with 5% w/v GelMA can provide a suitable microenvironment for laden bone marrow stem cells. Finally, it is demonstrated that the printed microdroplets can be used in building microspheroidal organoids, in drug controlled release, and in 3D bioprinting as biobricks. This method shows great potential use in cell therapy, drug delivery, and organoid building.


Assuntos
Bioimpressão/métodos , Gelatina/química , Hidrogéis/química , Metacrilatos/química , Viscosidade
15.
J Am Chem Soc ; 139(25): 8428-8431, 2017 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-28594548

RESUMO

This report details a general and enantioselective means for the synthesis of alkyl-substituted aziridines. This protocol offers a direct route for the synthesis of alkyl-substituted chiral aziridines from achiral starting materials. Readily accessed allylic hydroxylamine esters undergo copper hydride-catalyzed intramolecular hydroamination with a high degree of regio- and enantiocontrol to afford the aziridine products in good to excellent yields in highly enantioenriched form. The utility of the products derived from this method is further demonstrated through derivatization of the chiral aziridine products to obtain a diverse array of functionalized enantioenriched amines.


Assuntos
Aziridinas/química , Cobre/química , Aminação , Catálise , Ciclização , Estrutura Molecular , Estereoisomerismo
16.
Org Lett ; 19(7): 1698-1701, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28349698

RESUMO

The first enantioselective total synthesis of the epipolythiodiketopiperazine (ETP) natural product (-)-acetylapoaranotin (3) is reported. The concise synthesis was enabled by an eight-step synthesis of a key cyclohexadienol-containing amino ester building block. The absolute stereochemistry of both amino ester building blocks used in the synthesis is set through catalytic asymmetric (1,3)-dipolar cycloaddition reactions. The formal syntheses of (-)-emethallicin E and (-)-haemotocin are also achieved through the preparation of a symmetric cyclohexadienol-containing diketopiperazine.


Assuntos
Dicetopiperazinas/química , Dissulfetos/química , Reação de Cicloadição , Estrutura Molecular , Estereoisomerismo
17.
Intravital ; 5(2)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27790387

RESUMO

Tumor hypoxia is linked to tumor progression, metastasis, and therapy resistance. However, the underlying mechanisms behind this linkage are not fully understood. Here we present a novel fluorescent mCherry hypoxia-responsive marker that can be used in real time imaging to specifically and sensitively identify hypoxic cells in vivo at single cell resolution. Tumors derived from triple negative tumor cells expressing the hypoxia marker reveal that the hypoxic tumor cells congregate near flowing blood vessels. Using multiphoton microscopy, hypoxic MDA-MB-231 cells were directly visualized and showed a more persistent slow migration phenotype as compared to normoxic cells in the same field in vivo. Hypoxic tumor cells are enriched in the cell population that migrates toward human epithelial growth factor gradients in vivo, and has increased collagen degradation and intravasation activity, characteristics of dissemination and metastasis competent tumor cells. The hypoxia probe introduced in this study provides a specific reporter of hypoxic cell phenotypes in vivo which reveals new insights into the mechanisms by which hypoxia is linked to metastasis.

18.
Angew Chem Int Ed Engl ; 53(24): 6206-10, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24777757

RESUMO

The concise total syntheses of the bis(pyrroloindolines) (-)-lansai B and (+)-nocardioazines A and B are reported. The key pyrroloindoline building blocks are rapidly prepared by enantioselective formal [3+2] cycloaddition reactions. The macrocycle of (+)-nocardioazine A is constructed by an unusual intramolecular diketopiperazine formation.


Assuntos
Ácidos Heterocíclicos/química , Produtos Biológicos , Reação de Cicloadição , Estrutura Molecular , Estereoisomerismo
19.
Tetrahedron ; 69(27-28): 5622-5633, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24039305

RESUMO

The (R)-BINOL•SnCl4-catalyzed formal (3 + 2) cycloaddition between 3-substituted indoles and benzyl 2-trifluoroacetamidoacrylate is a direct, enantioselective method to prepare pyrroloindolines from simple starting materials. However, under the originally disclosed conditions, the pyrroloindolines are formed as mixtures of diastereomers, typically in the range of 3:1 to 5:1 favoring the exo-product. The poor diastereoselectivity detracts from the synthetic utility of the reaction. We report here that use of methyl 2-trifluoroacetamidoacrylate in conjunction with (R)-3,3'-dichloro-BINOL•SnCl4 provides the corresponding pyrroloindolines with improved diastereoselectivity (typically ≥10:1). Guided by mechanistic studies, a one-flask synthesis of enantioenriched indolines by in situ reduction of a persistent iminium ion is also described.

20.
Org Biomol Chem ; 10(33): 6740-6, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22805766

RESUMO

A naphthalimide-rhodamine B derivative was synthesized as a fluorescence turn-ON chemodosimeter for Sn(4+). A colour change and marked enhancement of fluorescence was found in the presence of Sn(4+), Cu(2+) and Cr(3+) due to the ring open reaction of rhodamine and a fluorescence resonance energy transfer process. Addition of the strong chelating agent ethylenediaminetetraacetic acid disodium salt (EDTA) partly released the cation from the complex with Sn(4+) and restored the yellow fluorescence. In addition, the compound can be used as a fluorescent probe for Sn(4+) in biological systems and may act as a tool with which to study the physiological functions of tin or pathogenesis in the human body.


Assuntos
Corantes Fluorescentes/química , Naftalimidas/química , Rodaminas/química , Espectrometria de Fluorescência/métodos , Estanho/análise , Sobrevivência Celular , Quelantes/química , Colorimetria/métodos , Ácido Edético/química , Fluorescência , Células HeLa , Humanos , Microscopia Confocal , Sensibilidade e Especificidade
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