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1.
Food Chem ; 367: 130762, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34390912

RESUMO

Inhibitory effects of flavonoids on starch digestibility were well known, but the structural mechanism was not clear. This study was focused on the diverse effect of quercetin and rutin on digestibility of Tartary buckwheat starch. Results showed that quercetin and rutin reduced the starch digestion by altering starch structure in bound forms and inhibiting digestive enzyme activity in free forms simultaneously, and quercetin showed a stronger effect than rutin. Molecular docking and saturation transfer difference-nuclear magnetic resonance (STD-NMR) revealed different binding site of rutin from quercetin was due to its hydroxyl and hydrogen on the glycoside structure. Rutin interacted with enzymes mainly by CH and OH on the glycoside structure which induced steric hindrance and restricted the inhibitory effect of quercetin fraction. The glycoside structure weakened inhibition of rutin on digestive enzymes in free forms rather than influence its anti-digestive effects in bound forms with starch.


Assuntos
Fagopyrum , Rutina , Sítios de Ligação , Digestão , Simulação de Acoplamento Molecular , Quercetina , Amido
2.
Elife ; 102021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34792465

RESUMO

Two neural circuits control the release of vasopressin in response to eating and drinking before there are any detectable changes in blood water levels.

3.
Angew Chem Int Ed Engl ; 60(49): 25771-25775, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606160

RESUMO

The frustrated Lewis pair (FLP) derived from 2,6-lutidine and B(C6 F5 )3 is shown to mediate the catalytic hydrogenation of CO2 using H2 as the reductant and a silylhalide as an oxophile. The nature of the products can be controlled with the judicious selection of the silylhalide and the solvent. In this fashion, this metal-free catalysis affords avenues to the selective formation of the disilylacetal (R3 SiOCH2 OSiR3 ), methoxysilane (R3 SiOCH3 ), methyliodide (CH3 I) and methane (CH4 ) under mild conditions. DFT studies illuminate the complexities of the mechanism and account for the observed selectivity.

4.
J Hazard Mater ; 424(Pt A): 127303, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34601405

RESUMO

The development of convenient assays for the determination of hydrazine (N2H4) has drawn significant attention due to the high toxicity of this substance. Herein, we developed a concise, rapid and ultrasensitive surface-enhanced Raman scattering (SERS) sensor for N2H4 detection based on alpha-cyclodextrin-silver nanoparticles (α-CD-AgNPs) modified by 4-mercaptobenzaldehyde (4-MBA). The 4-MBA molecules can specifically capture the N2H4 molecules and undergo a Schiff base reaction. As a result, this induces the aggregation of nanoparticles and generates a new characteristic peak at 1529 cm-1 that is attributed to CN and CC vibrations. Compared with noble metal nanoparticles, 4-MBA not only formed AgS bonds but could also be fixed in the cavity of cyclodextrin to produce a more stable and stronger SERS signal. The SERS intensity at 1529 cm-1 and the logarithm of the concentration of N2H4 presented a good linear relationship from 10-9 to 10-7 M with an unprecedented limit of detection (LOD) of 38 pM. The proposed SERS sensor exhibited satisfactory selectivity and reproducibility and was applied to detect N2H4 in real and complex water samples. We expect this assay to be a promising alternative tool for the on-site detection of N2H4.

5.
Materials (Basel) ; 14(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34640144

RESUMO

The purpose of this study was to develop a flexible substrate methylcellulose-decorated silver nanoparticles (MC/Ag NPs) film and explore its application in fruits and vegetables by surface enhanced Raman spectroscopy (SERS) technology for rapid detection of pesticides. The performance of the MC/Ag NPs film substrate was characterized by Nile blue A (NBA), and the detection limit was as low as 10-8 M. The substrate also exhibited satisfactory Raman signal strength after two months of storage. The impressive sensitivity and stability were due to the excellent homogeneity of the silver nanoparticles that were grown in situ in the methylcellulose matrix, which generated "hot spots" between the silver nanoparticles without a large amount of aggregation, and resulted in the ultra-high sensitivity and excellent stability of the MC/Ag NPs film substrate. The MC/Ag NPs film substrate was used to detect thiram pesticides on tomato and cucumber peels, and the minimum detectable level of thiram was 2.4 ng/cm2, which was much lower than the maximum residue level. These results indicate that the MC/Ag NPs film is sensitive to rapid detection of multiple pesticides in food.

6.
Front Plant Sci ; 12: 754982, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630498

RESUMO

Autophagy is a ubiquitous process used widely across plant cells to degrade cellular material and is an important regulator of plant growth and various environmental stress responses in plants. The initiation and dynamics of autophagy in plant cells are precisely controlled according to the developmental stage of the plant and changes in the environment, which are transduced into intracellular signaling pathways. These signaling pathways often regulate autophagy by mediating TOR (Target of Rapamycin) kinase activity, an important regulator of autophagy initiation; however, some also act via TOR-independent pathways. Under nutrient starvation, TOR activity is suppressed through glucose or ROS (reactive oxygen species) signaling, thereby promoting the initiation of autophagy. Under stresses, autophagy can be regulated by the regulatory networks connecting stresses, ROS and plant hormones, and in turn, autophagy regulates ROS levels and hormone signaling. This review focuses on the latest research progress in the mechanism of different external signals regulating autophagy.

7.
Chem Asian J ; 16(22): 3640-3644, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592053

RESUMO

Reactions of benzyl potassium species with CO are shown to proceed via transient carbene-like intermediates that can undergo either dimerization or further CO propagation. In a sterically unhindered case, formal dimerization of the carbene is the dominant reaction pathway, as evidenced by the isolation of ((Ph3 SiO)(PhCH2 )C)2 2 and PhCH2 C(O)CH(OH)CH2 Ph 3. Reactions with increasingly sterically encumbered reagents show competitive reaction pathways involving intermolecular dimerization leading to species analogous to 2 and 3 and those containing newly-formed five-membered rings tBu2 C6 H2 (C(OSiR3 )C(OSiR3 )CH2 ) (R=Me 6, Ph 7). Even further encumbered reagents proceed to either dimerize or react with additional CO to give a ketene-like intermediates, thus affording a 7-membered tropolone derivative 14 or the dione (3,5-tBu2 C6 H3 )3 C6 H2 CH2 C(O))2 15.

8.
Angew Chem Int Ed Engl ; 60(46): 24534-24542, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34505339

RESUMO

Even populations of clonal cells are heterogeneous, which requires high-throughput analysis methods with single-cell sensitivity. Here, we propose a rapid, label-free single-cell analytical method based on active capillary dielectric barrier discharge ionization mass spectrometry, which can analyze multiple metabolites in single cells at a rate of 38 cells/minute. Multiple cell types (HEK-293T, PANC-1, CFPAC-1, H6c7, HeLa and iBAs) were discriminated successfully. We found evidence for abnormal lipid metabolism in pancreatic cancer cells. We also analyzed gene expression in a cancer genome atlas dataset and found that the mRNA level of a critical enzyme of lipid synthesis (ATP citrate lyase, ACLY) was upregulated in human pancreatic ductal adenocarcinoma (PDAC). Moreover, both an ACLY chemical inhibitor and a siRNA approach targeting ACLY could suppress the viability of PDAC cells. A significant reduction in lipid content in treated cells indicates that ACLY could be a potential target for treating pancreatic cancer.

9.
Angew Chem Int Ed Engl ; 60(48): 25281-25285, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34559447

RESUMO

Synthesis of value-added products from simple C1 feedstocks is an attractive alternative avenue to traditional fossil fuels. Hexa-substituted benzene derivatives are highly useful molecules but are often challenging to prepare. Herein, we report that the lithium complex [(Ph2 P(S))2 CLi2 (THF)]2 1 reacts with CO lead to C-C bond formation and migration of a Ph2 P(S)-fragment affording 2. Subsequent reaction with N2 O results in oxidative cleavage of a P-C bond affording [Ph2 P(S)OLi(THF)2 ]2 4 and the anionic ketene-derivative Ph2 P(S)CCOLi(THF)2 5. Heating 5 prompts cyclotrimerization giving the hexa-substituted benzene derivative [Ph2 P(S)CCOLi(THF)2 ]3 6 regioselectively. This transition metal-free protocol to a hexa-substituted benzene is viable on a gram scale and permits the incorporation of 13 C labels. The mechanisms of these reactions are detailed via extensive DFT computations.

10.
Bioinorg Chem Appl ; 2021: 2586990, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490051

RESUMO

In this work, quercetin was loaded in the highly-porous lactose via the adsorption of quercetin molecules in ethanol. The method aims to improve the quercetin solubility and the loading capacity of lactose. The method relates to the synthesis of the highly-porous lactose with a particle size of ∼35 µm, a mean pore width of ∼30 nm, a BET surface area of 35.0561 ± 0.4613 m2/g, and a BJH pore volume of ∼0.075346 cc/g. After the quercetin loading in ethanol, BET surface area and BJH pore volume of porous lactose were reduced to 28.8735 ± 0.3526 m2/g and 0.073315 cc/g, respectively. The reduction rate was based on the quercetin loading efficiency of highly-porous lactose. DSC analysis and XRD analysis suggest that the sediments of quercetin in the nanopores of porous lactose are crystalline. FTIR spectroscopy results suggest that there is no significant interaction between quercetin and lactose. The highly-porous lactose had a higher loading efficiency of 20.3% (w/w) compared to the α-lactose (with 5.2% w/w). The release rates of quercetin from the highly-porous lactose tablets were faster compared to the conventional α-lactose carrier.

11.
BMC Vet Res ; 17(1): 308, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34537035

RESUMO

BACKGROUND: PCV3 is a pathogen associated with porcine dermatitis and nephropathy syndrome (PDNS)-like clinical signs, reproductive failure, and cardiac and multiorgan inflammation, which was newly identified in 2016 in sows in USA. Recently, PCV3 has also been identified from several non-porcine species like (cattle, dog, wild boar, deer, mice and ticks). However, PCV3 infection in donkey is not well established. Since 2019, 300 blood samples were collected from female donkey, which was characterized by abortion and sterility, in Liaocheng city of China. RESULTS: In the present study, an investigation of PCV3 in donkey blood samples was undertaken employing by real time PCR. Positive rates of PCV3 in donkeys reach to 21.0 %. In addition, one full-length PCV3 genome sequence was obtained, and it had a highest identity with porcine circovirus 3 PCV3/CN/Nanjing2017 strain and is clustered to PCV3a genotype based on ORF2 sequences. CONCLUSIONS: This is the first report of detection of PCV3 from female donkeys presenting reproductive failure in large-scale donkey farms, China. In addition, the PCV3 strain identified in this study shared the closest relationship with those from porcine, suggesting that PCV3 may be transmitted from pigs to donkeys. Totally, PCV3 infection in donkey should be concerned although the association between it and reproductive failure are not better understood.


Assuntos
Aborto Animal/virologia , Infecções por Circoviridae/veterinária , Circovirus/classificação , Circovirus/fisiologia , Equidae , Infertilidade Feminina/veterinária , Filogenia , Animais , Infecções por Circoviridae/complicações , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/virologia , Circovirus/isolamento & purificação , Feminino , Infertilidade Feminina/complicações , Infertilidade Feminina/virologia
12.
J Vis Exp ; (175)2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34542536

RESUMO

Hepatic metastasis of colorectal cancer (CRC) is a leading cause of cancer-related death. Cancer-associated fibroblasts (CAFs), a major component of the tumor microenvironment, play a crucial role in metastatic CRC progression and predict poor patient prognosis. However, there is a lack of satisfactory mouse models to study the crosstalk between metastatic cancer cells and CAFs. Here, we present a method to investigate how liver metastasis progression is regulated by the metastatic niche and possibly could be restrained by stroma-directed therapy. Portal vein injection of CRC organoids generated a desmoplastic reaction, which faithfully recapitulated the fibroblast-rich histology of human CRC liver metastases. This model was tissue-specific with a higher tumor burden in the liver when compared to an intra-splenic injection model, simplifying mouse survival analyses. By injecting luciferase-expressing tumor organoids, tumor growth kinetics could be monitored by in vivo imaging. Moreover, this preclinical model provides a useful platform to assess the efficacy of therapeutics targeting the tumor mesenchyme. We describe methods to examine whether adeno-associated virus-mediated delivery of a tumor-inhibiting stromal gene to hepatocytes could remodel the tumor microenvironment and improve mouse survival. This approach enables the development and assessment of novel therapeutic strategies to inhibit hepatic metastasis of CRC.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Organoides , Veia Porta , Microambiente Tumoral
13.
ACS Omega ; 6(30): 19717-19730, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34368559

RESUMO

After paraquat (PQ) poisoning, it is difficult to accurately diagnose patients' condition by only measuring their blood PQ concentration. Therefore, it is important to establish an accurate method to assist in the diagnosis of PQ poisoning, especially in the early stages. In this study, a gas chromatography-mass spectrometry (GC-MS) metabonomics strategy was established to obtain metabolite information. A random forest algorithm was used to search for potential biomarkers of PQ poisoning, and data mining and network pharmacological analysis were used to evaluate the active components, drug-disease targets, and key pathways of Xuebijing (XBJ) injection in the treatment of PQ-induced pulmonary fibrosis. Targets from the network pharmacology analysis and metabolites from plasma metabolomics were jointly analyzed to select crucial metabolic pathways. Finally, molecular docking technology and in vitro experiments were used to verify the pathway targets to further reveal the potential mechanisms underlying the antipulmonary fibrosis effect of XBJ. Metabonomics studies showed that l-valine, glycine, citric acid, d-mannose, d-galactose, maltose, l-tryptophan, and arachidonic acid contributed more to the differentiation of different groups than other metabolites. Compared with the control group, the PQ poisoning group had higher levels of l-valine, glycine, citric acid, l-tryptophan, and arachidonic acid, and lower levels of d-mannose, d-galactose, and maltose. After treatment with XBJ injection, the relative levels of these metabolites were reversed. The network pharmacological analysis screened a total of 180 targets, mainly involving multiple signaling pathways and metabolic pathways, which jointly played an antipulmonary fibrosis effect. Based on the combined analysis of 180 targets and 8 different metabolites, arachidonic acid metabolism was selected as the key metabolic pathway. Molecular docking analysis showed that the XBJ compound had strong binding activity with the target protein. Western blot results showed that XBJ injection could reduce the inflammatory response by downregulating the expressions of p-p65, p-IKBα, and p-IKKß, thus inhibiting the development of PQ-induced pulmonary fibrosis. In summary, the combined results from metabolomics and network pharmacology studies showed that Xuebijing has the characteristics of multitarget, multichannel, and multicomponent action in the treatment of pulmonary fibrosis caused by PQ.

14.
Biomed Res Int ; 2021: 5561221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414236

RESUMO

Brucea javanica oil (BJO) is beneficial for the treatment of ulcerative colitis (UC), and that quassinoids in particular brusatol are bioactive components. However, it is still uncertain whether or not other components in BJO, such as oleic acid and fatty acids, have an anti-UC effect. The present study is aimed at comparing the anti-UC effects between brusatol-enriched BJO (BE-BJO) and brusatol-free BJO (BF-BJO) and at exploring the effects and mechanisms of BE-BJO on colon inflammation and intestinal epithelial barrier function. Balb/C mice received 3% (wt/vol) DSS for one week to establish the UC model. Different doses of BE-BJO, BF-BJO, or BJO were treated. The result illustrated that BE-BJO alleviated DSS-induced loss of body weight, an increase of disease activity index (DAI), and a shortening of colon, whereas BF-BJO did not have these protective effects. BE-BJO treatment improved the morphology of colon tissue, inhibited the production and release of TNF-α, IFN-γ, IL-6, and IL-1ß in the colon tissue, and reversed the decreased expressions of ZO-1, occludin, claudin-1, and E-cadherin induced by DSS but augmented claudin-2 expression. Mechanistically, BE-BJO repressed phosphorylation of NF-κB subunit p65, suppressed RhoA activation, downregulated ROCK, and prevented phosphorylation of myosin light chain (MLC) in DSS-treated mice, indicating that the protective effect of BE-BJO is attributed to suppression of NF-κB and RhoA/ROCK signaling pathways. These findings confirm that brusatol is an active component from BJO in the treatment of UC.


Assuntos
Brucea/química , Colite/tratamento farmacológico , Sulfato de Dextrana/efeitos adversos , Óleos Vegetais/administração & dosagem , Quassinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Quassinas/farmacologia , Resultado do Tratamento , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
15.
Oncol Rep ; 46(4)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34435654

RESUMO

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that the tumor images shown in Fig. 6B bore unexpected similarities to data appearing in different form in other articles by different authors. In addition, there were potential anomalies associated with the cell migration assay data shown in Fig. 2E. Owing to the fact that some of the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Oncology Reports, the Editor has decided that this paper should be retracted from the Journal. The authors agree with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Oncology Reports 39: 695-702, 2018; DOI: 10.3892/or.2017.6119].

16.
Org Lett ; 23(16): 6272-6277, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34328334

RESUMO

An efficient synthesis of indolo[2,1-a]benzazepinones through rhodium-catalyzed cascade reactions of 2-arylindoles with allyl alcohols has been developed. This work expands the scope of products that are available through C-H activation/intramolecular annulation reactions of 2-arylindoles in organic synthesis.

17.
Org Lett ; 23(15): 5952-5957, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34323501

RESUMO

The Rh(III)-catalyzed dual directing group assisted C-H activation/annulation of 3-arylisoxazolones with propargyl alcohols has been developed, which expands the application scope of isoxazolones in organic synthesis. This protocol also worked well with 3-aryl-1,4,2-dioxazol-5-ones to produce synthetically and biologically important 4-arylisoquinolones.

18.
DNA Cell Biol ; 40(9): 1167-1176, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34255539

RESUMO

Skeletal muscle has great plasticity. An increase in protein degradation can cause muscle atrophy. Atrogin-1 and muscle ring finger-1 (MuRF1) are dramatically upregulated in various muscle atrophy. Inhibition of Atrogin-1 and MuRF1 protects against muscle atrophy. MiR-29 plays an important regulatory role in skeletal muscle development. However, the function of miR-29 in skeletal muscle protein metabolism is not clear. To investigate the function of miR-29, we generated miR-29 knockout mice and the miR-29ab1 cluster overexpression mice. The disruption of miR-29 led to severe atrophy of skeletal muscle during puberty, and the muscle-specific overexpression of the miR-29ab1 cluster protected against denervation-induced and fasting-induced muscle atrophy. Furthermore, the overexpression of miR-29a, b mimics in myotubes resisted the muscle atrophy. MuRF1 was the direct target gene of miR-29a, b. These results demonstrate that miR-29ab1 cluster plays a critical role in the maintenance of skeletal muscle. MiR-29ab1 cluster is the excellent inhibitor of MuRF1, ultimately indicating that miR-29ab1 cluster is good therapeutic molecule candidate for adulthood.


Assuntos
MicroRNAs/fisiologia , Desenvolvimento Muscular , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Mioblastos
19.
Nanotechnology ; 32(37)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34111847

RESUMO

Electrocatalysis of oxygen evolution reaction (OER), one of the most important members in clean and efficient energy conversion, requires increasing studies on reaction process analysis, catalyst investigation and evaluation and so on throughin situexperiments. The bottleneck is the difficulties on clear and precise understanding towards the multi-step reactions with fast reaction rates. Interdigitated array (IDA) electrodes with sensitive responses on the generation, transfer and collection of reaction products are proposed and utilized as a convenient and effective tool toin situmonitor and characterize the reaction thermodynamics and kinetics information. Herein, nickel-iron hydroxide, a promising and novel OER catalyst, is chosen as the candidate to demonstrate the merit of IDA on studying the OER. With the generator-collector mode, the real-time oxygen evolution process is monitored precisely with the IDA collector, distinguished it from the general catalytic current which is normally recorded with conventional electrochemical method. In another word, the actual faradaic efficiency was observed experimentally with IDA electrodes, which is often misled as 100% in many works. The diffusion of the reaction products has been 'seen' as well with the generator-collector mode. This general tool (IDA) may make more contributions on the study of reaction process of all electrocatalytical reactions.

20.
Cell Rep ; 35(13): 109299, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34192549

RESUMO

The sterol regulatory element-binding protein (SREBP) pathway monitors the cellular cholesterol level through sterol-regulated association between the SREBP cleavage-activating protein (Scap) and the insulin-induced gene (Insig). Despite structural determination of the Scap and Insig-2 complex bound to 25-hydroxycholesterol, the luminal domains of Scap remain unresolved. In this study, combining cryogenic electron microscopy (cryo-EM) analysis and artificial intelligence-facilitated structural prediction, we report the structure of the human Scap/Insig-2 complex purified in digitonin. The luminal domain loop 1 and a co-folded segment in loop 7 of Scap resemble those of the luminal/extracellular domain in NPC1 and related proteins, providing clues to the cholesterol-regulated interaction of loop 1 and loop 7. An additional luminal interface is observed between Scap and Insig. We also show that Scap(D428A), which inhibits SREBP activation even under sterol depletion, exhibits an identical conformation with the wild-type protein when complexed with Insig-2, and its constitutive suppression of the SREBP pathway may also involve a later step in protein trafficking.

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