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1.
Int J Ophthalmol ; 17(8): 1462-1468, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39156778

RESUMO

AIM: To analyze the distribution of fibrovascular proliferative membranes (FVPMs) in proliferative diabetic retinopathy (PDR) patients that treated with pars plana vitrectomy (PPV), and to evaluate the outcomes separately. METHODS: This was a retrospective and cross-sectional study. Consecutive 25-gauge (25-G) PPV cases operated for PDR from May 2018 to April 2020. According to the FVPMs images outlined after operations, subjects were assigned into three groups: arcade type group, juxtapapillary type group, and central type group. All patients were followed up for over one year. General characteristics, operation-related variables, postoperative parameters and complications were recorded. RESULTS: Among 103 eyes recruited, the FVPMs distribution of nasotemporal and inferiosuperioral was significantly different (both P<0.01), with 95 (92.23%) FVPMs located in the nasal quadrants, and 74 (71.84%) in the inferior. The eyes with a central FVPM required the longest operation time, with silicon oil used in most patients, generally combined with tractional retinal detachment (RD) and rhegmatogenous RD, the worst postoperative best-corrected visual acuity (BCVA) and the highest rates of recurrent RD (all P<0.05). FVPM type, age of onset diabetes mellitus, preoperative BCVA, and combined with tractional RD and rhegmatogenous RD were significantly associated with BCVA improvement (all P<0.05). Compared with the central type group, the arcade type group had higher rates of BCVA improvement. CONCLUSION: FVPMs are more commonly found in the nasal and inferior mid-peripheral retina in addition to the area of arcade vessels. Performing 25-G PPV for treating PDR eyes with central FVPM have relatively worse prognosis.

2.
Heliyon ; 10(14): e34498, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39082026

RESUMO

Background: Sepsis, a severe infectious disease, carries a high mortality rate. Early detection and prompt treatment are crucial for reducing mortality and improving prognosis. The aim of this research is to develop a clinical prediction model using machine learning algorithms, leveraging complete blood cell (CBC) parameters, to detect sepsis at an early stage. Methods: The study involved 572 patients admitted to West China Hospital of Sichuan University between July 2020 and September 2021. Among them, 215 were diagnosed with sepsis, while 357 had local infections. Demographic information was collected, and 57 CBC parameters were analyzed to identify potential predictors using techniques such as the Least Absolute Shrinkage and Selection Operator (LASSO), Random Forest (RF), Support Vector Machine (SVM), and eXtreme Gradient Boosting (XGBoost). The prediction model was built using Logistic Regression and evaluated for diagnostic specificity, discrimination, and clinical applicability including metrics such as the area under the curve (AUC), calibration curve, clinical impact curve, and clinical decision curve. Additionally, the model's diagnostic performance was assessed on a separate validation cohort. Shapley's additive explanations (SHAP), and breakdown (BD) profiles were used to explain the contribution of each variable in predicting the outcome. Results: Among all the machine learning methods' prediction models, the LASSO-based model (λ = min) demonstrated the highest diagnostic performance in both the discovery cohort (AUC = 0.9446, P < 0.001) and the validation cohort (AUC = 0.9001, P < 0.001). Furthermore, upon local analysis and interpretation of the model, we demonstrated that LY-Z, MO-Z, and PLT-I had the most significant impact on the outcome. Conclusions: The predictive model based on CBC parameters can be utilized as an effective approach for the early detection of sepsis.

3.
Int J Surg ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954670

RESUMO

BACKGROUND: Carbon nanoparticle suspension injection (CNSI) and indocyanine green (ICG) have both been applied intraoperatively to facilitate lymphatic mapping and postoperatively to sort lymph nodes (LNs) in gastric cancer patients. However, no study has compared the two tracers in gastric cancer patients. MATERIALS AND METHODS: This prospective randomized controlled trial was conducted from January 2022 to March 2023. Patients with potentially resectable gastric cancer (cT1-4a N0/+ M0) were randomized to the CNSI or ICG group. RESULTS: This study enrolled 96 patients. Ninety patients were in the modified intention-to-treat population, including 46 patients (32 males and 14 females; mean [SD] age, 57.4 [9.4] years) in the CNSI group and 44 patients (31 males and 13 females; mean [SD] age, 60.8 [8.8] years) in the ICG group. The mean (SD) number of retrieved LNs was 69.8 (21.9) and 53.6 (17.2) in the CNSI and ICG groups, respectively (P<0.001). The mean (SD) number of retrieved micro-LNs was 19.9 (13.3) and 11.6 (9.9) in the CNSI and ICG groups, respectively (P=0.001). The mean (SD) number of metastatic LNs was 8.1 (11.9) and 5.2 (9.2) in the CNSI and ICG groups, respectively (P=0.19). CONCLUSIONS: Compared with ICG, CNSI can increase the number of LNs detected, especially micro-LNs. Both tracers have high diagnostic value for detecting metastatic LNs. CNSI-guided lymphography may be a superior method for improving the accuracy of LN dissection.

4.
Exp Cell Res ; 439(1): 114096, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768700

RESUMO

Early vascularization plays an essential role during the whole process in bone regeneration because of the function of secreting cytokines, transporting nutrients and metabolic wastes. As the preliminary basis of bone repair, angiogenesis is regulated by immune cells represented by macrophages to a great extent. However, with the discovery of the endolymphatic circulation system inside bone tissue, the role of vascularization became complicated and confusing. Herein, we developed a macrophage/lymphatic endothelial cells (LECs)/human umbilical vein endothelial cells (HUVECs) co-culture system to evaluate the effect of macrophage treated lymphatic endothelial cells on angiogenesis in vitro and in vivo. In this study, we collected the medium from macrophage (CM) for LECs culture. We found that CM2 could promote the expression of LECs markers and migration ability, which indicated the enhanced lymphogenesis. In addition, the medium from LECs was collected for culturing HUVECs. The CM2-treated LECs showed superior angiogenesis property including the migration capacity and expression of angiogenetic markers, which suggested the superior vascularization. Rat femoral condyle defect model was applied to confirm the hypothesis in vivo. Generally, M2-macrophage treated LECs showed prominent angiogenetic potential coupling with osteogenesis.


Assuntos
Técnicas de Cocultura , Células Endoteliais da Veia Umbilical Humana , Macrófagos , Neovascularização Fisiológica , Osteogênese , Humanos , Animais , Células Endoteliais da Veia Umbilical Humana/metabolismo , Macrófagos/metabolismo , Ratos , Células Endoteliais/metabolismo , Movimento Celular , Ratos Sprague-Dawley , Regeneração Óssea/fisiologia , Camundongos , Células Cultivadas , Masculino , Angiogênese
5.
World J Gastrointest Oncol ; 16(3): 1029-1045, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577446

RESUMO

BACKGROUND: CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors, including gastric cancer (GC), and is associated with tumor progression and immune infiltration; however, the roles and mechanisms of CALD1 in epithelial-mesenchymal transition (EMT) in GC are unknown. AIM: To investigate the role and mechanism of CALD1 in GC progression, invasion, and migration. METHODS: In this study, the relationship between CALD1 and GC, as well as the possible network regulatory mechanisms of CALD1, was investigated by bioinformatics and validated by experiments. CALD1-siRNA was synthesized and used to transfect GC cells. Cell activity was measured using the CCK-8 method, cell migration and invasive ability were measured using wound healing assay and Transwell assay, and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot. A GC cell xenograft model was established to verify the results of in vitro experiments. RESULTS: Bioinformatics results showed that CALD1 was highly expressed in GC tissues, and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC. The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression, and a prognostic model was constructed and evaluated. The experimental results were consistent with the results of the bioinformatics analysis. The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1, with the strongest expression found in AGS and MKN45 cells. Cell activity was significantly reduced after CALD1-siRNA transfection of AGS and MKN45 cells. The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection, and the related mRNA and protein expression was altered. According to bioinformatics findings in GC samples, the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway, and was closely related to the PI3K-Akt signaling pathway. Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K, p-AKT, and p-mTOR, members of the PI3K-Akt pathway,while decreasing the expression of PTEN; PI3K-Akt inhibitor treatment decreased the expression of PI3K, p-AKT, and p-mTOR in cells overexpressing CALD1 (still higher than that in the normal group), but increased the expression of PTEN (still lower than that in the normal group). CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor. Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor. The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1, whereas the effect of overexpression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor. Animal experiments showed that tumour growth was slow after inhibition of CALD1, and the expression of some PI3K-Akt and EMT pathway proteins was altered. CONCLUSION: Increased expression of CALD1 is a key factor in the progression, invasion, and metastasis of GC, which may be associated with regulating the PI3K-Akt pathway to promote EMT.

6.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38675422

RESUMO

Lycii Radicis Cortex (LRC) is a traditional medicine in East Asia with various beneficial effects, including antioxidant, anti-inflammatory, anti-tumor, anti-diabetic, and anti-depressant properties. However, its potential effects on skeletal muscle atrophy have not been studied. In this study, the protective effects of LRC extract (LRCE) on dexamethasone (DEX)-induced muscle atrophy were investigated in C2C12 myotubes and mice. We evaluated the effect of LRCE on improving muscle atrophy using a variety of methods, including immunofluorescence staining, quantitative polymerase chain reaction (qPCR), Western blot, measurements of oxidative stress, apoptosis, ATP levels, and muscle tissue analysis. The results showed that LRCE improved myotube diameter, fusion index, superoxide dismutase (SOD) activity, mitochondrial content, ATP levels, expression of myogenin and myosin heavy chain (MHC), and reduced reactive oxygen species (ROS) production in dexamethasone-induced C2C12 myotubes. LRCE also enhanced protein synthesis and reduced protein degradation in the myotubes. In mice treated with DEX, LRCE restored calf thickness, decreased mRNA levels of muscle-specific RING finger protein 1 (MuRF1) and atrogin-1, and increased insulin-like growth factor 1 (IGF-1) mRNA level. Moreover, LRCE also repaired gastrocnemius muscle atrophy caused by DEX. Although human studies are not available, various preclinical studies have identified potential protective effects of LRCE against muscle atrophy, suggesting that it could be utilized in the prevention and treatment of muscle atrophy.

7.
Chem Sci ; 15(5): 1752-1757, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38303957

RESUMO

We present a metal-free strategy to access fluoroalkyl-olefin linkages from fluoroalkane precursors and vinyl-pinacol boronic ester (BPin) reagents. This reaction sequence is templated by the boron reagent, which induces C-C bond formation upon oxidation. We developed this strategy into a one-pot synthetic protocol using RCF2H precursors directly with vinyl-BPin reagents in the presence of a Brønsted base, which tolerated oxygen- and nitrogen-containing heterocycles, and aryl halogens. We also found that HCF3 (HCF-23; a byproduct of the Teflon industry) and CH2F2 (HCF-32; a low-cost refrigerant) are amenable to this protocol, representing distinct strategies to generate RCF2H and RCF3 molecules. Finally, we demonstrate that the vinyldifluoromethylene products can be readily derivatized, representing an avenue for late-stage modification after installing the fluoroalkyl unit.

8.
Int J Biol Macromol ; 260(Pt 2): 129573, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266829

RESUMO

Polyphenol-starch complexes exhibit synergistic and beneficial effects on both polyphenols and resistant starches. This study evaluates the inhibitory effects and mechanisms of α-amylase on a Lonicera caerulea berry polyphenol-wheat starch (LPWS) complex following high hydrostatic pressure treatments of 400 MPa for 30 min and 600 MPa for 30 min. The IC50 values for α-amylase inhibition by the complex were 3.61 ± 0.10 mg/mL and 3.42 ± 0.08 mg/mL at a 10 % (w/w) polyphenol content. This interaction was further supported by Fourier-transform infrared spectroscopy and circular dichroism, which confirmed that the alpha helix component of the secondary structure of α-amylase was reduced due to the complex. Multifluorescence spectroscopy revealed that the complex induces changes in the microenvironment of fluorophores surrounding the α-amylase active site. Molecular dynamics simulations and molecular docking revealed that the active site of amylose within the complex becomes enveloped in polyphenol clusters. This wrapping effect reduced the hydrogen bonds between amylose and α-amylase, decreasing from 16 groups to just one group. In summary, the LPWS complex represents a low-digestible carbohydrate food source, thus laying the groundwork for the research and development of functional foods aimed at postprandial hypoglycemic effects.


Assuntos
Lonicera , Amido , Amido/química , alfa-Amilases/química , Amilose , Frutas/metabolismo , Simulação de Dinâmica Molecular , Simulação de Acoplamento Molecular , Polifenóis/farmacologia , Dicroísmo Circular , Digestão
9.
J Colloid Interface Sci ; 657: 913-920, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38091914

RESUMO

Chirality dynamic tuning plays fundamental roles in chemistry, material science and biological system. Herein, a pair of azobenzene-bridged bis-tryptophan enantiomers (Azo-di-d/l-Trp) were designed and synthesized via simple reactions. With the fuel of glucono-δ-lactone (GdL), releasing protons during its hydrolysis, the alkaline solution of Azo-di-d/l-Trp gradually self-assembled into contrast chiral helical structures and displayed magnitude and mirror image of circular dichroism (CD) signals. While the chiral helices converted to CD silent nanoparticles when the azobenzene moiety isomerized from trans- to cis-form under UV irradiation. More importantly, this chiroptical switch, displaying reversible interconversion between chiral amplification and silent, can be smartly controlled via photoirradiation at various wavelengths.

10.
Biochem Biophys Res Commun ; 692: 149360, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38081108

RESUMO

BACKGROUND: Myocardial infarction (MI) dramatically changes the mechanical stress, which is intensified by the fibrotic remodeling. Integrins, especially the αV subunit, mediate mechanical signal and mechanoparacrine of transforming growth factor ß1 (TGF-ß1) in various organ fibrosis by activating CFs into myofibroblasts (MFBs). We investigated a possible role of integrin αV mediated mechanoparacrine of TGF-ß1 in MFBs activation for fibrous reparation in mice with MI. METHODS: Heart samples from MI, sham, or MI plus cilengitide (14 mg/kg, specific integrin αV inhibitor) treated mice, underwent functional and morphological assessments by echocardiography, and histochemistry on 7, 14 and 28 days post-surgery. The mechanical and ultrastructural changes of the fibrous scar were further evaluated by atomic mechanics microscope (AFM), immunofluorescence, second harmonic generation (SHG) imaging, polarized light and scanning electron microscope, respectively. Hydroxyproline assay was used for total collagen content, and western blot for protein expression profile examination. Fibroblast bioactivities, including cell shape, number, Smad2/3 signal and expression of extracellular matrix (ECM) related proteins, were further evaluated by microscopic observation and immunofluorescence in polyacrylamide (PA) hydrogel with adjustable stiffness, which was re-explored in fibroblast cultured on stiff matrix after silencing of integrin αV. The content of total and free TGF-ß1 was tested by enzyme-linked immunosorbent assay (ELISA) in both infarcted tissue and cell samples. RESULT: Increased stiffness with heterogeneity synchronized with integrin αV and alpha smooth muscle actin (α-SMA) positive MFBs accumulation in those less mature fibrous areas. Cilengitide abruptly reduced collagen content and disrupted collagen alignment, which also decreased TGF-ß1 bioavailability, Smad2/3 phosphorylation, and α-SMA expression in the fibrous area. Accordingly, fibroblast on stiff but not soft matrix exhibited obvious MFB phenotype, as evidenced by enlarged cell, hyperproliferation, well-developed α-SMA fibers, and elevated ECM related proteins, while silencing of integrin αV almost abolished this switch via attenuating paracrine of TGF-ß1 and nuclear translocation of Smad2/3. CONCLUSION: This study illustrated that increased tissue stiffness activates CFs into MFBs by integrin αV mediated mechanoparacrine of TGF-ß1, especially in immature scar area, which ultimately promotes fibrous scar maturation.


Assuntos
Infarto do Miocárdio , Miofibroblastos , Animais , Camundongos , Actinas/metabolismo , Cicatriz/metabolismo , Colágeno/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Fibrose , Integrina alfaV/metabolismo , Infarto do Miocárdio/patologia , Miofibroblastos/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
11.
Bone Res ; 11(1): 64, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097598

RESUMO

Given afferent functions, sensory nerves have recently been found to exert efferent effects and directly alter organ physiology. Additionally, several studies have highlighted the indirect but crucial role of sensory nerves in the regulation of the physiological function of osteoclasts. Nonetheless, evidence regarding the direct sensory nerve efferent influence on osteoclasts is lacking. In the current study, we found that high levels of efferent signals were transported directly from the sensory nerves into osteoclasts. Furthermore, sensory hypersensitivity significantly increased osteoclastic bone resorption, and sensory neurons (SNs) directly promoted osteoclastogenesis in an in vitro coculture system. Moreover, we screened a novel neuropeptide, Cyp40, using an isobaric tag for relative and absolute quantitation (iTRAQ). We observed that Cyp40 is the efferent signal from sensory nerves, and it plays a critical role in osteoclastogenesis via the aryl hydrocarbon receptor (AhR)-Ras/Raf-p-Erk-NFATc1 pathway. These findings revealed a novel mechanism regarding the influence of sensory nerves on bone regulation, i.e., a direct promoting effect on osteoclastogenesis by the secretion of Cyp40. Therefore, inhibiting Cyp40 could serve as a strategy to improve bone quality in osteoporosis and promote bone repair after bone injury.


Assuntos
Reabsorção Óssea , Osteogênese , Humanos , Peptidilprolil Isomerase/metabolismo , Osteoclastos/metabolismo , Reabsorção Óssea/metabolismo
12.
Phys Chem Chem Phys ; 25(44): 30373-30380, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37909301

RESUMO

Structurally precise metal nanoclusters with a facile synthetic process and high catalytic performance have been long pursued. These atomically precise nanocatalysts are regarded as model systems to study structure-performance relationships, surface coordination chemistry, and the reaction mechanism of heterogeneous metal catalysts. Nevertheless, the research on silver-based nanoclusters for driving chemical transformations is sluggish in comparison to gold counterparts. Herein, we report the one-step synthesis of Pt/Ag alloy nanoclusters of [PtAg9(C18H12Br3P)7Cl3](C18H12Br3P), which are highly active in catalysing cycloaddition reactions of CO2 and epoxides. The cluster was obtained in a rather simple way with the reduction of silver and platinum salts in the presence of ligands in one pot. The molecular structure of the titled cluster describes the protection of the Pt-centred Ag9 crown by the shell of phosphine ligands and halides. Its electronic structure, as revealed by density function theoretical calculations, adopts a superatomic geometry with 1S21P6 configuration. Interestingly, the cluster displays high activity in the formation of cyclic carbonates from CO2 under mind conditions.

13.
Nature ; 624(7992): 672-681, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37935376

RESUMO

Trace-amine-associated receptors (TAARs), a group of biogenic amine receptors, have essential roles in neurological and metabolic homeostasis1. They recognize diverse endogenous trace amines and subsequently activate a range of G-protein-subtype signalling pathways2,3. Notably, TAAR1 has emerged as a promising therapeutic target for treating psychiatric disorders4,5. However, the molecular mechanisms underlying its ability to recognize different ligands remain largely unclear. Here we present nine cryo-electron microscopy structures, with eight showing human and mouse TAAR1 in a complex with an array of ligands, including the endogenous 3-iodothyronamine, two antipsychotic agents, the psychoactive drug amphetamine and two identified catecholamine agonists, and one showing 5-HT1AR in a complex with an antipsychotic agent. These structures reveal a rigid consensus binding motif in TAAR1 that binds to endogenous trace amine stimuli and two extended binding pockets that accommodate diverse chemotypes. Combined with mutational analysis, functional assays and molecular dynamic simulations, we elucidate the structural basis of drug polypharmacology and identify the species-specific differences between human and mouse TAAR1. Our study provides insights into the mechanism of ligand recognition and G-protein selectivity by TAAR1, which may help in the discovery of ligands or therapeutic strategies for neurological and metabolic disorders.


Assuntos
Proteínas de Ligação ao GTP , Receptores Acoplados a Proteínas G , Animais , Humanos , Camundongos , Aminas/metabolismo , Anfetamina/metabolismo , Antipsicóticos/química , Antipsicóticos/metabolismo , Sítios de Ligação , Catecolaminas/agonistas , Catecolaminas/química , Catecolaminas/metabolismo , Microscopia Crioeletrônica , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/ultraestrutura , Ligantes , Simulação de Dinâmica Molecular , Mutação , Polifarmacologia , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestrutura , Especificidade da Espécie , Especificidade por Substrato
14.
Nanoscale ; 15(44): 17818-17824, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37668358

RESUMO

Reported herein is the facial synthesis, molecular structure, and catalysis of a Pt/Ag nanocluster costabilized by organic ligands of phosphines and inorganic ligands of chlorides. The nanocluster with molecular formula of [PtAg18(dppp)6Cl8](SbF6)2 has been obtained facilely by the one pot method. The structure of the cluster could be anatomized as the stabilizaiton of PtAg12-centered icosahedral core by the metalloligand of dppp-Ag-Cl, in which Cl- not only caps the surface Ag atoms but also binds the core and surface motifs. Featuring eight free electrons in its structure, the cluster exhibits high stability. More interestingly, the exposure of surface metal sites endows the cluster with counterintutively  high catalytic activity in hydrogenation reactions.

15.
Dalton Trans ; 52(30): 10332-10337, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37449919

RESUMO

A facile synthesis of atomically precise metal nanoclusters, especially those decorated with functional groups, is the prerequisite for finding applications in special fields and studying structure-and-property relationships. The exploration of simple and efficient synthetic prototypes for introducing functional ligands (such as ferrocene) into cluster moieties is thus of high interest. In this work, a type of reducing agent of dppfCuBH4 (dppf is 1,1'-bis(diphenyphosphino)ferrocene) is introduced for the first time to prepare ferrocene-functionalized metal nanoclusters. Two new clusters of [Ag25Cu4(dppf)6(3-F-PhCC)12Cl6]3+ (1) and [Ag4(dppf)5Cl2]2+ (2) have been obtained from the simple synthetic method. The two compounds have been fully characterized by advanced techniques of electrospray ionization mass spectroscopy (ESI-MS), nuclear magnetic resonance (NMR), and ultraviolet-visible spectroscopy (UV-Vis). The total structure of the clusters, as determined by X-ray single-crystal diffraction, describes the Ag13@Ag12Cu4(dppf)6(3-F-PhCC)12Cl6 core-shell structure of 1 and [Ag2Cl(dppf)2]+-dppf-[Ag2Cl(dppf)2]+ polymeric structure of 2. This work opens the door to employing dppfCuBH4 as a functional reducing agent to discover many underlying metal nanoclusters and even other nanomaterials which feature ferrocene-groups.

16.
Foods ; 12(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37372634

RESUMO

Xylanases are the preferred enzymes for the extracting of oligosaccharides from wheat bran. However, free xylanases have poor stability and are difficult to reuse, which limit their industrial application. In the present study, we covalently immobilized free maleic anhydride-modified xylanase (FMA-XY) to improve its reusability and stability. The immobilized maleic anhydride-modified xylanase (IMA-XY) exhibited better stability compared with the free enzyme. After six repeated uses, 52.24% of the activity of the immobilized enzyme remained. The wheat bran oligosaccharides extracted using IMA-XY were mainly xylopentoses, xylohexoses, and xyloheptoses, which were the ß-configurational units and α-configurational units of xylose. The oligosaccharides also exhibited good antioxidant properties. The results indicated that FMA-XY can easily be recycled and can remain stable after immobilization; therefore, it has good prospects for future industrial applications.

17.
BMC Surg ; 23(1): 147, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37264328

RESUMO

BACKGROUND: There are only a few epidemiological reports available for reference. The clinicopathological features are not clear, so there is no consensus on treating rectal multiple neuroendocrine neoplasms. This study aims to summarize the clinicopathological characteristics and preliminarily discuss the clinical diagnosis and treatment of rectal multiple neuroendocrine neoplasms. METHODS: This study retrospectively analyzed rectal neuroendocrine neoplasm patients diagnosed and treated at the Fourth Hospital of Hebei Medical University from February 2007 to May 2021. The clinicopathological characteristics of rectal multiple neuroendocrine neoplasms were summarized and analyzed in combination with 14 studies on rectal multiple neuroendocrine neoplasms. RESULTS: The incidence of RM-NENs accounted for 3.8% of all R-NENs in this study. The number of tumors varied to some extent, the size of tumors was basically no more than 10 mm, and there were more G1 grade tumors. In the analysis of 46 cases with known lymph node metastasis, the difference in lymph node metastasis rate between the number of tumors < 8 and ≥ 8 was statistically significant (p = 0.002). CONCLUSIONS: The incidence of rectal multiple neuroendocrine neoplasms accounted for 3.8% of all rectal neuroendocrine neoplasms. For rectal multiple neuroendocrine neoplasms, the lymph node metastasis rate was higher when the number of tumors was ≥ 8. The influence of the number of tumors on lymph node metastasis should be considered in the selection of treatment.


Assuntos
Tumores Neuroendócrinos , Neoplasias Retais , Humanos , Prognóstico , Metástase Linfática , Estudos Retrospectivos , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/patologia , Neoplasias Retais/diagnóstico , Neoplasias Retais/epidemiologia , Neoplasias Retais/patologia
18.
Food Funct ; 14(10): 4807-4823, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37128963

RESUMO

Chinese chestnut shell is a by-product of chestnut food processing and is rich in polyphenols. This study sought to investigate the effect of chestnut shell polyphenol extract (CSP) on weight loss and lipid reduction in a 12-week high-fat diet (HFD)-induced murine obesity model. CSP (300 mg per kg body weight) was administered intragastrically daily. AG490, a JAK2 protein tyrosine kinase inhibitor, was also intraperitoneally injected. The results showed that an HFD induced leptin resistance (LR). Compared to corresponding values in the HFD group, CSP treatment improved blood lipid levels, weight, and leptin levels in obese mice (p < 0.01). Additionally, CSP treatment enhanced enzyme activity by improving total antioxidant capacity, attenuating oxidative stress, and reducing fat droplet accumulation and inflammation in the liver, epididymal, and retroperitoneal adipose tissue. CSP also activated the LEPR-JAK2/STAT3-PTP1B-SOCS-3 signal transduction pathway in hypothalamus tissue and improved LR while regulating the expression of proteins related to lipid metabolism (PPARγ, FAS, and LPL) in white adipose tissue in the retroperitoneal cavity. However, the amelioration of lipid metabolism by CSP was dependent on JAK2. Molecular docking simulation further demonstrated the strong binding affinity of procyanidin C1 (-10.3983297 kcal mol-1) and procyanidin B1 (-9.12686729 kcal mol-1) to the crystal structure of JAK2. These results suggest that CSP may be used to reduce HFD-induced obesity with potential application as a functional food additive.


Assuntos
Dieta Hiperlipídica , Leptina , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Fagaceae , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leptina/metabolismo , Lipídeos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Nozes , Obesidade/metabolismo , Extratos Vegetais , Estruturas Vegetais , Polifenóis/farmacologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
19.
Inorg Chem ; 62(13): 5088-5094, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36947487

RESUMO

Little advance has been made toward developing alternative bottom-up synthetic strategies for N-heterocyclic carbene (NHC)-stabilized gold nanoclusters, although this unique class of nanomaterials has exhibited exciting properties. We report in this work a simple and straightforward approach toward NHC-ligated gold nanoclusters by using imidazolium salts rather than free carbenes or NHC-coordinated gold complexes (NHC-Au-X, X is counterions) as precursors. Illustrated here is a one-pot and one-step preparation of an NHC-stabilized Au13Br4 cluster that features a distinct molecular formula, surface motifs, and assembling modes via chemical reduction of dpaAu, NaOMe, and FNHCBn·HBr by NaBH4 (Hdpa is dipyridylamine; FNHCBn·HBr is 1,3-dibenzyl-5,6-difluoro-1H-benzo[d]imidazole-3-ium bromide). In situ UV-vis and NMR studies have elucidated the base-assisted formation of NHCs from imidazolium salts for the protection of the metal core. This work not only reports a new NHC-ligated superatom that completes the Au13 library, thus facilitating structure-property studies, but also opens the door to explore underlying analogues in a facile and reasonable way.

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