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Metalation of metal-organic frameworks (MOFs) has been developed as a prominent strategy for materials functionalization for pore chemistry modulation and property optimization. By introducing exotic metal ions/complexes/nanoparticles onto/into the parent framework, many metallized MOFs have exhibited significantly improved performance in a wide range of applications. In this review, we focus on the research progress in the metalation of metal-organic frameworks during the last five years, spanning the design principles, synthetic strategies, and potential applications. Based on the crystal engineering principles, a minor change in the MOF composition through metalation would lead to leveraged variation of properties. This review starts from the general strategies established for the incorporation of metal species within MOFs, followed by the design principles to graft the desired functionality while maintaining the porosity of frameworks. Facile metalation has contributed a great number of bespoke materials with excellent performance, and we summarize their applications in gas adsorption and separation, heterogeneous catalysis, detection and sensing, and energy storage and conversion. The underlying mechanisms are also investigated by state-of-the-art techniques and analyzed for gaining insight into the structure-property relationships, which would in turn facilitate the further development of design principles. Finally, the current challenges and opportunities in MOF metalation have been discussed, and the promising future directions for customizing the next-generation advanced materials have been outlined as well.
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Localized surface plasmon resonances (LSPRs) can enhance the electromagnetic fields on metallic nanostructures upon light illumination, providing an approach for manipulating light-matter interactions at the sub-wavelength scale. However, currently, there is no thorough investigation of the physical mechanism in the dynamic formation of the strongly coupled LSPRs on sub-5 nm plasmonic cavities at the sub-picosecond scale. In this work, through femtosecond broadband transient absorption spectroscopy, we reveal the dynamic ultrastrong coupling processes in a nanoparticle-in-trench (NPiT) structure containing 2 nm gap cavities, and demonstrate a coherent motional coupling between vibrating AuNPs and the nanogaps. We achieve a maximum Rabi splitting energy of â¼660 meV in the sub-picosecond hot-electron relaxation time scale under the resonant excitation of the nanogap cavity's LSPR, reaching the ultrastrong coupling regime. This leads to a change of global vibration modes for the 2 nm gap cavity, potentially related to the dynamical Casimir effect with nanogap resonators.
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Library matching by comparing carbon-13 nuclear magnetic resonance (13C NMR) spectra with spectral data in the library is a crucial method for compound identification. In our previous paper, we introduced a deep contrastive learning system called CReSS, which used a library that contained more structures. However, CReSS has two limitations: there were no unknown structures in the library, and a redundant library reduces the structure-elucidation accuracy. Herein, we replaced the oversize traditional libraries with focused libraries containing a small number of molecules. A previously generative model, CMGNet, was used to generate focused libraries for CReSS. The combined model achieved a Top-10 accuracy of 54.03% when tested on 6,471 13C NMR spectra. In comparison, CReSS with a random reference structure library achieved an accuracy of only 9.17%. Furthermore, to expand the advantages of the focused libraries, we proposed SAmpRNN, which is a recurrent neural network (RNN). With the large focused library amplified by SAmpRNN, the structure-identification accuracy of the model increased in 70.0% of the 30 random example cases. In general, cross-modal retrieval between 13C NMR spectra and structures based on focused libraries (CFLS) achieved high accuracy and provided more accurate candidate structures than traditional libraries for compound identification.
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Imagen por Resonancia Magnética , Espectroscopía de Resonancia MagnéticaRESUMEN
OBJECTIVES: This study aimed to systematically assess the methodological quality and key recommendations of the guidelines for the diagnosis and treatment of liver failure (LF), furnishing constructive insights for guideline developers and equipping clinicians with evidence-based information to facilitate informed decision-making. DATA SOURCES: Electronic databases and manual searches from January 2011 to August 2023. STUDY SELECTION: Two reviewers independently screened titles and abstracts, then full texts for eligibility. Fourteen guidelines were included. DATA EXTRACTION AND SYNTHESIS: Two reviewers extracted data and checked by two others. Methodological quality of the guidelines was appraised using the Appraisal of Guidelines for Research and Evaluation II tool. Of the 14 guidelines, only the guidelines established by the Society of Critical Care Medicine and the American College of Gastroenterology (2023) achieved an aggregate quality score exceeding 60%, thereby meriting clinical recommendations. It emerged that there remains ample room for enhancement in the quality of the guidelines, particularly within the domains of stakeholder engagement, rigor, and applicability. Furthermore, an in-depth scrutiny of common recommendations and supporting evidence drawn from the 10 adult LF guidelines unveiled several key issues: controversy exists in the recommendation, the absence of supporting evidence and confusing use of evidence for recommendations, and a preference in evidence selection. CONCLUSIONS: There are high differences in methodological quality and recommendations among LF guidelines. Improving these existing problems and controversies will benefit existing clinical practice and will be an effective way for developers to upgrade the guidelines.
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We report on the continuous-wave (CW) and, for what we believe to be the first time, passively mode-locked (ML) laser operation of an Yb3+-doped YSr3(PO4)3 crystal. Utilizing a 976-nm spatially single-mode, fiber-coupled laser diode as pump source, the Yb:YSr3(PO4)3 laser delivers a maximum CW output power of 333â mW at 1045.8â nm with an optical efficiency of 55.7% and a slope efficiency of 60.9%. Employing a quartz-based Lyot filter, an impressive wavelength tuning range of 97â nm at the zero level was achieved in the CW regime, spanning from 1007â nm to 1104â nm. In the ML regime, incorporating a commercially available semiconductor saturable absorber mirror (SESAM) to initiate and maintain soliton-like pulse shaping, the Yb:YSr3(PO4)3 laser generated pulses as short as 61 fs at 1062.7â nm, with an average output power of 38â mW at a repetition rate of â¼66.7â MHz.
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We present the growth, spectroscopy, continuous-wave (CW) and passively mode-locked (ML) operation of a novel "mixed" tetragonal calcium rare-earth aluminate crystal, Yb3+:Ca(Gd,Y)AlO4. The absorption, stimulated-emission, and gain cross-sections are derived for π and σ polarizations. The laser performance of a c-cut Yb:Ca(Gd,Y)AlO4 crystal is studied using a spatially single-mode, 976-nm fiber-coupled laser diode as a pump source. A maximum output power of 347â mW is obtained in the CW regime with a slope efficiency of 48.9%. The emission wavelength is continuously tunable across 90â nm (1010 - 1100â nm) using a quartz-based Lyot filter. With a commercial SEmiconductor Saturable Absorber Mirror to initiate and maintain ML operation, soliton pulses as short as 35 fs are generated at 1059.8â nm with an average output power of 51â mW at â¼65.95â MHz. The average output power can be scaled to 105â mW for slightly longer pulses of 42 fs at 1063.5â nm.
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Vinylidene ortho-quinone methides (VQMs) have been proven to be versatile and crucial intermediates in the catalytic asymmetric reaction in last decade, and thus have drawn considerable concentrations on account of the practical application in the construction of enantiomerically pure functional organic molecules. However, in comparison to the well established chiral Brønsted base-catalyzed asymmetric reaction via VQMs, chiral Brønsted acid-catalyzed reaction is rarely studied and there is no systematic summary to date. In this review, we summarize the recent advances in the chiral Brønsted acid-catalyzed asymmetric reaction via VQMs according to three types of reactions: a) intermolecular asymmetric nucleophilic addition to VQMs; b) intermolecular asymmetric cycloaddition of VQMs; c) intramolecular asymmetric cyclization of VQMs. Finally, we put forward the remained challenges and opportunities for potential breakthroughs in this area.
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BACKGROUND: Smoking rationalisation beliefs are a huge barrier to quitting smoking. What types of rationalisations should be emphasised in smoking cessation interventions? Although past literature has confirmed the negative relationship between those beliefs and motivation to stop smoking, little is known regarding the importance and performance of those beliefs on motivation with varying cigarette dependence. The study aimed to ascertain rationalisations that are highly important for motivation yet perform poorly in different cigarette dependence groups. METHODS: The cross-sectional study was conducted from November 19 to December 9, 2023 in Guiyang City, China. Adult male current smokers were enrolled. Partial least squares structural equation modelling was used to test the hypothesis. The multi-group analysis was used to determine the moderating effect of cigarette dependence, and the importance-performance map analysis was utilised to assess the importance and performance of rationalisations. RESULTS: A total of 616 adult male current smokers were analysed, and they were divided into the low cigarette dependence group (n = 297) and the high cigarette dependence group (n = 319). Except for risk generalisation beliefs, smoking functional beliefs (H1: -ß = 0.131, P < 0.01), social acceptability beliefs (H3: ß = -0.258, P < 0.001), safe smoking beliefs (H4: ß = -0.078, P < 0.05), self-exempting beliefs (H5: ß = -0.244, P < 0.001), and quitting is harmful beliefs (H6: ß = -0.148, P < 0.01) all had a significant positive influence on motivation. Cigarette dependence moderated the correlation between rationalisations and motivation. In the high-dependence group, the social acceptability beliefs and smoking functional beliefs were located in the "Concentrate Here" area. In the low-dependence group, the social acceptability beliefs were also situated in there. CONCLUSIONS: Social acceptability beliefs and smoking functional beliefs showed great potential and value for improvement among high-dependence smokers, while only social acceptability beliefs had great potential and value for improvement among low-dependence smokers. Addressing these beliefs will be helpful for smoking cessation. The multi-group analysis and the importance-performance map analysis technique have practical implications and can be expanded to other domains of health education and intervention practice.
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Motivación , Cese del Hábito de Fumar , Humanos , Masculino , China , Estudios Transversales , Adulto , Cese del Hábito de Fumar/psicología , Persona de Mediana Edad , Fumadores/psicología , Fumadores/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Adulto Joven , Tabaquismo/psicología , Tabaquismo/terapia , Pueblos del Este de AsiaRESUMEN
The clinical advantage staging and underlying mechanisms of Wangbi Tablets against knee osteoarthritis(KOA) were studied based on the "disease-formula" interaction network. Firstly, the clinical symptoms and related genes corresponding to Wangbi Tablets and KOA in the acute, remission, and recovery phases were collected from clinical guidelines/consensus and SoFDA database, and the putative targets of Wangbi Tablets were obtained from ETCM 2.0. Then, Jaccard similarity and cosine similarity were employed to assess the similarities of clinical symptoms, genes, and enriched pathways between Wangbi Tablets and KOA in different phases. The "disease-formula" interaction network of the drug targets and disease genes was constructed, and the key targets were screened by topological feature calculation. KEGG and Reactome database were used for the functional enrichment of the key targets, on the basis of which the functional characteristics of Wangbi Tablets against KOA in the acute, remission, and recovery phases were predicted. Finally, the SW1353 cells exposed to lipopolysaccharide were used to decipher the mechanism of Wangbi Tablets against KOA. The results showed that 92/3 921, 138/3 708, 139/3 800, and 196/3 946 clinical symptoms and the related genes corresponded to KOA in the acute, remission, and recovery phases and Wangbi Tablets were collected from SoFDA, and 260 putative targets of Wangbi Tablets were obtained from ETCM 2.0. Wangbi Tablets had highest similarity of clinical symptoms, genes, and enriched pathways with KOA in the remission phase and the secondary highest similarity with KOA in the recovery phase. The key targets of Wangbi Tablets mainly participated in the regulation of immunity-inflammation imbalance and exerted pain-relieving and bone-protecting effects to alleviate symptoms such as knee joint pain, joint swelling, soreness, fatigue, and dysfunction. Intriguingly, the key targets of Wangbi Tablets possessed antioxidant effects during KOA in the acute and remission phases, while they maintained material and energy metabolism homeostasis and protected vessels during KOA in the recovery phase. The cell experiment indicated that Wangbi Tablets down-regulated the expression of interleukin(IL)-6, IL-1ß, tumor necrosis factor-α(TNF-α), and Bcl-2-associated X protein(Bax)/B-cell lymphoma 2(Bcl-2) via regulating the phosphatidylinositol 3-kinase(PI3K)-protein kinase B(Akt) signaling pathway. The findings lay a theoretical foundation for further clarifying the clinical advantage stage and precise clinical application of Wangbi Tablets in treating KOA.
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Medicamentos Herbarios Chinos , Osteoartritis de la Rodilla , Comprimidos , Humanos , Medicamentos Herbarios Chinos/farmacología , Osteoartritis de la Rodilla/tratamiento farmacológico , Osteoartritis de la Rodilla/genética , Osteoartritis de la Rodilla/metabolismoRESUMEN
This study explored the biosynthesis of bufadienolides(BDs) in Bufo bufo gargarizans to solve the dilemma of the decreasing resources of B. bufo gargarizans and provide a theoretical basis for the sustainable utilization of the resources. Ultra-high performance liquid chromatography-Orbitrap-mass spectrometry(UHPLC-Orbitrap-MS) was employed to detect the synthesis sites of BDs in B. bufo gargarizans, and the results were verified by desorption electrospray ionization-mass spectrometry imaging(DESI-MSI) and homogenate incubation experiments. BDs in B. bufo gargarizans had the highest content in the liver and the highest concentration in the gallbladder, in addition to the parotid gland and skin, which suggested that the liver could synthesize BDs. The results of DESI-MSI also showed that BDs were mainly enriched in the liver rather than the immature parotid gland. The incubation experiment of liver homogenates demonstrated the liver of B. bufo gargarizans had the ability to synthesize BDs. This study showed that the liver was a major organ for the synthesis of BDs in B. bufo gargarizans during metamorphosis, development, and growth, which provided strong theoretical support for the biosynthesis of BDs and the sustainable utilization of B. bufo gargarizans resources.
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Bufanólidos , Animales , Bufo bufo , Distribución Tisular , Bufonidae , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and lethal malignancy with extremely poor patient survival rates. A key reason for the poor prognosis is the lack of effective diagnostic tools to detect the disease at curable, premetastatic stages. Tumor surgical resection is PDAC's first-line treatment, however distinguishing between cancerous and healthy tissue with current imaging tools remains a challenge. In this work, we report a DOTA-based fluorescent probe targeting plectin-1 for imaging PDAC with high specificity. To enable heterogeneous functionalization of the DOTA-core with multiple targeting peptide units and the fluorophore, a novel, fully clickable synthetic route that proceeds in one pot was developed. Extensive validation of the probe set the stage for PDAC detection in mice and human tissue. Altogether, these findings may pave the way for improved clinical understanding and early detection of PDAC progression as well as more accurate resection criteria.
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Medios de Contraste , Compuestos Heterocíclicos con 1 Anillo , Neoplasias Pancreáticas , Plectina , Humanos , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Plectina/metabolismo , Animales , Medios de Contraste/química , Ratones , Compuestos Heterocíclicos con 1 Anillo/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Carcinoma Ductal Pancreático/diagnóstico por imagen , Carcinoma Ductal Pancreático/patología , Imagen ÓpticaRESUMEN
This study aims to reveal the endogenous metabolic characteristics of acteoside in the young rat model of purinomycin aminonucleoside nephropathy(PAN) by non-targeted urine metabolomics and decipher the potential mechanism of action. Biochemical indicators in the urine of rats from each group were determined by an automatic biochemical analyzer. The potential biomarkers and related core metabolic pathways were identified by ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) combined with principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA). MetaboAnalyst 5.0 was used to establish the receiver operating characteristic(ROC) curve for evaluating the clinical diagnostic performance of core metabolites. The results showed that acteoside significantly decreased urinary protein-to-creatinine ratio in PAN young rats. A total of 17 differential metabolites were screened out by non-targeted urine metabolomics in PAN young rats and they were involved in phenylalanine metabolism and phenylalanine, tyrosine and tryptophan biosynthesis. Thirtten differential metabolites were screened by acteoside intervention in PAN young rats, and they were involved in phenylalanine metabolism and arginine and proline metabolism. Among them, leucylproline and acetophenone were the differential metabolites that were significantly recovered after acteoside treatment. These pathways suggest that acteoside treats PAN in young rats by regulating amino acid metabolism. The area under the curve of two core biomarkers, leucylproline and acetophenone, were both greater than 0.9. In summary, acteoside may restore amino acid metabolism by regulating endogenous differential metabolites in PAN young rats, which will help to clarify the mechanism of acteoside in treating chronic glomerulonephritis in children. The characteristic biomarkers screened out have a high diagnostic value for evaluating the treatment of chronic glomerulonephritis in children with acteoside.
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Glomerulonefritis , Puromicina Aminonucleósido , Humanos , Niño , Ratas , Animales , Metabolómica/métodos , Biomarcadores/orina , Cromatografía Líquida de Alta Presión/métodos , Acetofenonas , Fenilalanina , AminoácidosRESUMEN
This study comprehensively analyzed the active components of Sanhan Huashi Formula using qualitative and quantitative mass spectrometry techniques, laying the foundation for understanding its pharmacological substance basis. UHPLC-LTQ-Orbitrap-MS and GC-MS technologies were used to analyze and identify the volatile and non-volatile components in Sanhan Huashi Formula. UHPLC-QQQ-MS/MS technology was used to simultaneously determine the content of 27 major active components in the formula. The results showed that 308 major chemical components were identified in Sanhan Huashi Formula, among which 60 compounds were identified by comparing with reference standards, mainly including alkaloids, flavonoids, coumarins, triterpenoid saponins, amino acids, and nucleosides. GC-MS technology preliminarily identified 52 volatile compounds, with γ-eudesmol and ß-eudesmol as the main components. The quantitative results demonstrated good linearity(r>0.99) for the 27 active components, indicating the stability, simplicity, and reliability of the established method. Among them, amygdalin, nodakenin, arecoline, ephedrine, and pseudoephedrine had relatively high content and were presumably the main pharmacologically active substances. In conclusion, this study systematically and comprehensively characterized the major chemical components and patterns in Sanhan Huashi Formula, providing a basis for understanding its pharmacological mechanisms and clinical applications.
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Medicamentos Herbarios Chinos , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Reproducibilidad de los Resultados , Medicamentos Herbarios Chinos/químicaRESUMEN
Anterior subcutaneous internal fixation (INFIX) is one of the current representatives of minimally invasive fixation of injuries to the anterior pelvic ring. The nail insertion point of this technique is located at the anterior inferior iliac spinous screw, with an angle of 30° outward and 20° backward. Screw in at an angle, and note that the screw head should be above the deep fascia and maintain a safe distance of 20 to 25 mm from the bone surface. Its improved versions include 3 or 4 nails INFIX with added pubic tubercle screws, unilateral INFIX, short-rod INFIX, and double INFIX. These improvements further enhance stability. The lateral femoral cutaneous nerve (LFCN) is relatively easy to be damaged during anatomy, so special attention should be paid during the operation. Biomechanical stability has advantages over external fixation, and its application is flexible. It is not limited to pubic ramus fracture, symphyseal separation, etc. It also plays an important role in combined anterior and posterior ring fixation. It can be combined with posterior sacroiliac screws, iliac lumbar screws, etc. Fixed etc. Good clinical results have also been reported in children, pregnant women, and people with contraindications for subcutaneous connecting rods. In addition, the current application of robots, reduction frames and other technologies has greatly reduced the difficulty of reduction and improved the quality of closed reduction, making it possible to fix complex pelvic fracture. This technique has high reduction quality and is as effective as traditional steel plates. A common complication is LFCN injury. Careful exposure and adjustment of the position and depth of internal fixation during surgery can effectively avoid this complication.
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Fijación Interna de Fracturas , Huesos Pélvicos , Humanos , Fijación Interna de Fracturas/métodos , Huesos Pélvicos/lesiones , Huesos Pélvicos/cirugía , Fracturas Óseas/cirugíaRESUMEN
Carbon fiber reinforced composite structures have been a research hotspot in recent years, with 9 specimens designed for static tests under bending and torsion loads of CFRP concrete filled steel tubes. The torque angle (T-θ) curve was studied from an experimental perspective. Subsequently, a reasonable finite element model was established using ABAQUS software. In addition, the effects of changes in parameters such as the number of steel concrete strength, bending ratio, and steel ratio on C-CF-CFRP-ST bending and torsion specimens were studied through numerical parameter research. Finally, equations of bearing capacity of CFRP-concrete filled steel tube under coupled bending and torsion are proposed.
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BACKGROUND: A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde cholangiography. Anatomical irregularities within the extrahepatic bile duct may increase susceptibility to bile duct stones. AIM: To investigate the anatomical risk factors associated with extrahepatic bile ducts in patients diagnosed with choledocholithiasis, with a specific focus on preventing stone recurrence after surgical intervention and endoscopic lithotomy. METHODS: We retrospectively analyzed the medical records of 124 patients without choledocholithiasis and 108 with confirmed choledocholithiasis who underwent magnetic resonance cholangiopancreatography examinations at our center between January 2022 and October 2022. Logistic regression analyses were conducted to identify the anatomical risk factors influencing the incidence of common bile duct stones. RESULTS: Multivariate logistic regression analysis revealed that several factors independently contributed to choledocholithiasis risk. Significant independent risk factors for choledocholithiasis were diameter of the common hepatic [adjusted odds ratio (aOR) = 1.43, 95% confidence interval (CI): 1.07-1.92, adjusted P value = 0.016] and common bile (aOR = 1.68, 95%CI: 1.27-2.23, adjusted P value < 0.001) ducts, length of the common hepatic duct (aOR = 0.92, 95%CI: 0.84-0.99, adjusted P value = 0.034), and angle of the common bile duct (aOR = 0.92, 95%CI: 0.89-0.95, adjusted P value < 0.001). CONCLUSION: The anatomical features of the extrahepatic bile duct were directly associated with choledocholithiasis risk. Key risk factors include an enlarged diameter of the common hepatic and bile ducts, a shorter length of the common hepatic duct, and a reduced angle of the common bile duct.
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Aromatic-carbonyl (Ar···CâO) interactions, attractive interactions between the arene plane and the carbon atom of carbonyl, are in the infancy as one type of new supramolecular bonding forces. Here the study and functionalization of aromatic-carbonyl interactions in solution is reported. A combination of aromatic-carbonyl interactions and dynamic covalent chemistry provided a versatile avenue. The stabilizing role and mechanism of arene-aldehyde/imine interactions are elucidated through crystal structures, NMR studies, and computational evidence. The movement of imine exchange equilibria further allowed the quantification of the interplay between arene-aldehyde/imine interactions and dynamic imine chemistry, with solvent effects offering another handle and matching the electrostatic feature of the interactions. Moreover, arene-aldehyde/imine interactions enabled the reversal of kinetic and thermodynamic selectivity and sorting of dynamic covalent libraries. To show the functional utility diverse modulation of fluorescence signals is realized with arene-aldehyde/imine interactions. The results should find applications in many aspects, including molecular recognition, assemblies, catalysis, and intelligent materials.
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Six Cordyceps militaris polysaccharides (named CMP-1, CMP-2, CMP-3, CMP-4, CMP-9, and CMP-A) were obtained by fractional alcohol precipitation. The experimental results showed that the six Cordyceps militaris polysaccharides had similar chemical composition and spectral features, and different molecular weights, monosaccharide compositions and anti-tumor activities. Purification of CMP-9 yielded the small molecule polysaccharide LMW-CMP (3.06 kDa). Structural experiments showed that LMW-CMP is an α-glucan with (1 â 4)-α-D-Glcp as the main chain and a glucose branched chain attached at the O-6 position. The results of cell experiments showed that LMW-CMP could effectively inhibit the growth and proliferation of HepG2 cells, activate the downstream NF-κB signaling pathway through the MAPK pathway to induce apoptosis of HepG2 cells, and block apoptosis at the G1 phase. Animal experiments showed that LMW-CMP inhibited the proliferation of tumor cells in H22 tumor-bearing mice by improving the state of immune organs, increasing the activity of immune cells and cytokine levels in the body, and regulating the distribution of lymphocyte subpopulations, with a tumor inhibition rate of 45.70 % (200 mg/kg).
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The prevalence of methicillin-resistant Staphylococcus aureus (MRSA), one of the most important multidrug-resistant bacteria in clinic, has become a serious global health issue. In this study, we designed and synthesized a series of griseofamine A derivatives and evaluated their antibacterial profiles. In vitro assays found that compound 9o10 showed a remarkable improvement of antibacterial activity toward MRSA (MIC = 0.0625 µg/mL), compared with griseofamine A (MIC = 8 µg/mL) and vancomycin (MIC = 0.5 µg/mL) with low hemolysis and cytotoxicity. Its rapid bactericidal property was also confirmed by time-kill curve assay. Furthermore, compound 9o10 displayed weak drug resistance frequency. In in vivo experiment, compound 9o10 exhibited more potent antibacterial efficacy than vancomycin and excellent biosafety (LD50 > 2 g/kg). Preliminary mechanism study revealed compound 9o10 might involve antibacterial mechanisms contributing to membrane damage. Taken together, compound 9o10 possessed excellent inhibitory activity against MRSA in vitro and in vivo with low toxicity and drug resistance frequency, making it a promising hit compound for further development against MRSA infections.
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Antibacterianos , Diseño de Fármacos , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Relación Estructura-Actividad , Estructura Molecular , Animales , Relación Dosis-Respuesta a Droga , Humanos , RatonesRESUMEN
Photodynamic immunotherapy (PDI) is an innovative approach to cancer treatment that utilizes photodynamic therapy (PDT) and photosensitizers (PSs) to induce immunogenic cell death (ICD). However, currently most commonly used PSs have restricted capabilities to generate reactive oxygen species (ROS) via a type-II mechanism under hypoxic environments, which limits their effectiveness in PDI. To overcome this, we propose a novel approach for constructing oxygen independent PSs based on stable organic free-radical molecules. By fine-tuning the characteristics of tris(2,4,6-trichlorophenyl)-methyl (TTM) radicals through the incorporation of electron-donating moieties, we successfully found that TTMIndoOMe could produce substantial amounts of ROS even in hypoxic environments. In vitro experiments showed that TTMIndoOMe could effectively produce O2Ë-, kill tumor cells and trigger ICD. Moreover, in vivo experiments also demonstrated that TTMIndoOMe could further trigger anti-tumor immune response and exhibit a superior therapeutic effect compared with PDT alone. Our study offers a promising approach towards the development of next-generation PSs functioning efficiently even under hypoxic conditions and also paves the way for the creation of more effective PSs for PDI.