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Structural complexity brings a huge challenge to the analysis of sugar chains. As a single-molecule sensor, nanopores have the potential to provide fingerprint information on saccharides. Traditionally, direct single-molecule saccharide detection with nanopores is hampered by their small size and weak affinity. Here, a carbon nitride nanopore device is developed to discern two types of trisaccharide molecules (LeApN and SLeCpN) with minor structural differences. The resolution of LeApN and SLeCpN in the mixture reaches 0.98, which has never been achieved in solid-state nanopores so far. Monosaccharide (GlcNAcpN) and disaccharide (LacNAcpN) can also be discriminated using this system, indicating that the versatile carbon nitride nanopores possess a monosaccharide-level resolution. This study demonstrates that the carbon nitride nanopores have the potential for conducting structure analysis on single-molecule saccharides.
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BACKGROUND & AIMS: As the first approved medication for metabolic dysfunction-associated steatohepatitis (MASH), thyroid hormone receptor-beta (THR-ß) agonist MGL-3196 (Resmetirom) is highly spotlighted as the liver-directed, bioactive oral drug. However, it was also identified with remarkable heterogeneity of individual clinical efficacy and its interference with gut microbiota in host hepatoenteral circulation was still undocumented. METHODS: We compared MASH attenuation by MGL-3196 and its derivative drug HSK31679 between germ-free (GF) and specific-pathogen free (SPF) mice to evaluate the role of gut microbiota. Then cross-omics analyses of microbial metagenome, metabolome and single-cell RNA-sequencing were applied into the randomized, double-blind, placebo-controlled multiple-ascending-dose (MAD) cohort of HSK31679 treatment (n = 40), to comprehensively investigate the altered gut microbiota metabolism and circulating immune signatures. RESULTS: HSK31679 outperformed MGL-3196 in ameliorating MASH diet-induced steatohepatitis of SPF mice but not GF mice. In the MAD cohort of HSK31679, relative abundance of B. thetaiotaomicron was significantly enriched to impair glucosylceramide synthase (GCS)-catalyzed monoglucosylation of microbial Cer(d18:1/16:0) and Cer(d18:1/24:1). In stark contrast to the non-inferiority MASH resolution between MGL-3196 and HSK31679 for GFBTΔGCS mice, HSK31679 manifested superior steatohepatitis alleviation than MGL-3196 for GFBTWT mice, due to its steric hindrance with R123 and Y401 of gut microbial GCS. For participants with high fecal GCS activity, the administration of 160 mg HSK31679 induced a shift in peripheral compartments towards an immunosuppressive niche, characterized by decreased CD8α+ dendritic cells and MINCLE+ macrophages. CONCLUSIONS: This study provided novel insights into the indispensable gut microbiota for HSK31679 treatment, which revealed microbial GCS may serve as its prognostic biomarker of MASH treatment, as well as the new target for further strategies of microbiota-based MASH therapeutics. IMPACT AND IMPLICATIONS: Remarkable heterogeneity of individual clinical efficacy of THR-ß agonists and their interferences with microbiome in host hepatoenteral circulation are poorly understood. In our current germ-free mice models and randomized, double-blind multiple-dose cohort study, we identified microbial GCS as the prognostic biomarker of HSK31679 treatment, as well as the new target for further strategies of microbiota-based MASLD therapeutics.
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PURPOSE: Acute myocardial infarction (AMI) is a leading cause of mortality. Neutrophils penetrate injured heart tissue during AMI or ischemia-reperfusion (I/R) injury and produce inflammatory factors, chemokines, and extracellular traps that exacerbate heart injury. Inhibition of the TRAIL-DR5 pathway has been demonstrated to alleviate cardiac ischemia-reperfusion injury in a leukocyte-dependent manner. However, it remains unknown whether TRAIL-DR5 signaling is involved in regulating neutrophil extracellular traps (NETs) release. METHODS: This study used various models to examine the effects of activating the TRAIL-DR5 pathway with soluble mouse TRAIL protein and inhibiting the TRAIL-DR5 signaling pathway using DR5 knockout mice or mDR5-Fc fusion protein on NETs formation and cardiac injury. The models used included a co-culture model involving bone marrow-derived neutrophils and primary cardiomyocytes and a model of myocardial I/R in mice. RESULTS: NETs formation is suppressed by TRAIL-DR5 signaling pathway inhibition, which can lessen cardiac I/R injury. This intervention reduces the release of adhesion molecules and chemokines, resulting in decreased neutrophil infiltration and inhibiting NETs production by downregulating PAD4 in neutrophils. CONCLUSION: This work clarifies how the TRAIL-DR5 signaling pathway regulates the neutrophil response during myocardial I/R damage, thereby providing a scientific basis for therapeutic intervention targeting the TRAIL-DR5 signaling pathway in myocardial infarction.
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Studies have shown that protein phosphorylation plays an important role in morphine abuse. However, the neurobiological mechanism of protein phosphatase 2A (PP2A) underlying the morphine-priming process is still unclear. Here we constructed T29-2-Cre; PP2Afl/fl conditional knockout mice (KO) and investigated the role of hippocampal PP2A in morphine priming. We observed that the deficit of PP2A inhibited the priming behavior of morphine and blocked the priming-induced long-term potentiation (LTP) in the hippocampus of KO mice. Moreover, the expression levels of Rack1 and the membrane GluN2B were significantly reduced in the nucleus accumbens of KO mice compared with those in the control mice, which may be attributed to the decreased HDAC4 in the hippocampus of KO mice. Consistent with it, the similar inhibited priming effects were also observed in the wild-type mice treated with sodium butyrate (NaB)-a nonspecific inhibitor of histone deacetylases-3 h after morphine administration. Taken together, our results suggest that hippocampal PP2A may be involved in morphine priming through the PP2A/HDAC4/Rack1 pathway.
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Morfina , Proteína Fosfatasa 2 , Ratones , Animales , Morfina/farmacología , Morfina/metabolismo , Proteína Fosfatasa 2/metabolismo , Hipocampo/metabolismo , Potenciación a Largo Plazo , Ratones NoqueadosRESUMEN
Obtaining information about cellular interactions is fundamental to the elucidation of physiological and pathological processes. Proximity labeling technologies have been widely used to report cellular interactions in situ; however, the reliance on addition of tag molecules typically restricts their application to regions where tags can readily diffuse, while the application in, for example, solid tissues, is susceptible. Here, we propose an "in-situ-tag-generation mechanism" and develop the GalTag technology based on galactose oxidase (GAO) for recording cellular interactions within three-dimensional biological solid regions. GAO mounted on bait cells can in situ generate bio-orthogonal aldehyde tags as interaction reporters on prey cells. Using GalTag, we monitored the dynamics of cellular interactions and assessed the targeting ability of engineered cells. In particular, we recorded, for the first time, the footprints of Bacillus Calmette-Guérin (BCG) invasion into the bladder tissue of living mice, providing a valuable perspective to elucidate the anti-tumor mechanism of BCG.
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Galactosa Oxidasa , Animales , Ratones , Galactosa Oxidasa/metabolismo , Galactosa Oxidasa/química , Humanos , Comunicación CelularRESUMEN
BACKGROUND: In the primary analysis of the CLEAR study, lenvatinib plus pembrolizumab significantly improved progression-free survival and overall survival versus sunitinib in patients with advanced renal cell carcinoma (data cutoff Aug 28, 2020). We aimed to assess overall survival based on 7 months of additional follow-up. METHODS: This is a protocol-prespecified updated overall survival analysis (data cutoff March 31, 2021) of the open-label, phase 3, randomised CLEAR trial. Patients with clear-cell advanced renal cell carcinoma who had not received any systemic anticancer therapy for renal cell carcinoma, including anti-vascular endothelial growth factor therapy, or any systemic investigational anticancer drug, were eligible for inclusion from 200 sites (hospitals and cancer centres) across 20 countries. Patients were randomly assigned (1:1:1) to receive lenvatinib (20 mg per day orally in 21-day cycles) plus pembrolizumab (200 mg intravenously every 21 days; lenvatinib plus pembrolizumab group), lenvatinib (18 mg per day orally) plus everolimus (5 mg per day orally; lenvatinib plus everolimus group [not reported in this updated analysis]) in 21-day cycles, or sunitinib (50 mg per day orally, 4 weeks on and 2 weeks off; sunitinib group). Eligible patients were at least 18 years old with a Karnofsky performance status of 70 or higher. A computer-generated randomisation scheme was used, and stratification factors were geographical region and Memorial Sloan Kettering Cancer Center prognostic groups. The primary endpoint was progression-free survival assessed by independent imaging review according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). In this Article, extended follow-up analyses for progression-free survival and protocol-specified updated overall survival data are reported for the intention-to-treat population. No safety analyses were done at this follow-up. This study is closed to new participants and is registered with ClinicalTrials.gov, NCT02811861. FINDINGS: Between Oct 13, 2016, and July 24, 2019, 1417 patients were screened for inclusion in the CLEAR trial, of whom 1069 (75%; 273 [26%] female, 796 [74%] male; median age 62 years [IQR 55-69]) were randomly assigned: 355 (33%) patients (255 [72%] male and 100 [28%] female) to the lenvatinib plus pembrolizumab group, 357 (33%) patients (275 [77%] male and 82 [23%] female) to the sunitinib group, and 357 (33%) patients to the lenvatinib plus everolimus group (not reported in this updated analysis). Median follow-up for progression-free survival was 27·8 months (IQR 20·3-33·8) in the lenvatinib plus pembrolizumab group and 19·4 months (5·5-32·5) in the sunitinib group. Median progression-free survival was 23·3 months (95% CI 20·8-27·7) in the lenvatinib plus pembrolizumab group and 9·2 months (6·0-11·0) in the sunitinib group (stratified hazard ratio [HR] 0·42 [95% CI 0·34-0·52]). Median overall survival follow-up was 33·7 months (IQR 27·4-36·9) in the lenvatinib plus pembrolizumab group and 33·4 months (26·7-36·8) in the sunitinib group. Overall survival was improved with lenvatinib plus pembrolizumab (median not reached [95% CI 41·5-not estimable]) versus sunitinib (median not reached [38·4-not estimable]; HR 0·72 [95% CI 0·55-0·93]). INTERPRETATION: Efficacy benefits of lenvatinib plus pembrolizumab over sunitinib were durable and clinically meaningful with extended follow-up. These results support the use of lenvatinib plus pembrolizumab as a first-line therapy for patients with advanced renal cell carcinoma. FUNDING: Eisai and Merck Sharp & Dohme.
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Carcinoma de Células Renales , Neoplasias Renales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Everolimus , Estudios de Seguimiento , SunitinibRESUMEN
Pulmonary arterial hypertension (PAH) comprises a heterogeneous group of diseases with diverse aetiologies. It is characterized by increased pulmonary arterial pressure and right ventricular (RV) failure without specific drugs for treatment. Emerging evidence suggests that inflammation and autoimmune disorders are common features across all PAH phenotypes. This provides a novel idea to explore the characteristics of immunological disorders in PAH and identify immune-related genes or biomarkers for specific anti-remodelling regimens. In this study, we integrated three gene expression profiles and performed Gene Ontology (GO) and KEGG pathway analysis. CIBERSORT was utilized to estimate the abundance of tissue-infiltrating immune cells in PAH. The PPI network and machine learning were constructed to identify immune-related hub genes and then evaluate the relationship between hub genes and differential immune cells using ImmucellAI. Additionally, we implemented molecular docking to screen potential small-molecule compounds based on the obtained genes. Our findings demonstrated the density and distribution of infiltrating CD4 T cells in PAH and identified four immune-related genes (ROCK2, ATHL1, HSP90AA1 and ACTR2) as potential targets. We also listed 20 promising molecules, including TDI01953, pemetrexed acid and radotinib, for PAH treatment. These results provide a promising avenue for further research into immunological disorders in PAH and potential novel therapeutic targets.
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Insuficiencia Cardíaca , Hipertensión Arterial Pulmonar , Humanos , Hipertensión Arterial Pulmonar/tratamiento farmacológico , Hipertensión Arterial Pulmonar/genética , Simulación del Acoplamiento Molecular , Hipertensión Pulmonar Primaria Familiar , Insuficiencia Cardíaca/metabolismo , BiomarcadoresRESUMEN
Executing glycan editing at a molecular level not only is pivotal for the elucidation of complicated mechanisms involved in glycan-relevant biological processes but also provides a promising solution to potentiate disease therapy. However, the precision control of glycan modification or glyco-editing on a selected glycoprotein is by far a grand challenge. Of note is to preserve the intact cellular glycan landscape, which is preserved after editing events are completed. We report herein a versatile, traceless glycan modification methodology for customizing the glycoforms of targeted proteins (subtypes), by orchestrating chemical- and photoregulation in a protein-selective glycoenzymatic system. This method relies on a three-module, ligand-photocleavable linker-glycoenzyme (L-P-G) conjugate. We demonstrated that RGD- or synthetic carbohydrate ligand-containing conjugates (RPG and SPG) would not activate until after the ligand-receptor interaction is accomplished (chemical regulation). RPG and SPG can both release the glycoenzyme upon photoillumination (photoregulation). The adjustable glycoenzyme activity, combined with ligand recognition selectivity, minimizes unnecessary glycan editing perturbation, and photolytic cleavage enables precise temporal control of editing events. An altered target protein turnover and dimerization were observed in our system, emphasizing the significance of preserving the native physiological niche of a particular protein when precise modification on the carbohydrate epitope occurs.
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Carbohidratos , Polisacáridos , Ligandos , Polisacáridos/química , Glicoproteínas/químicaRESUMEN
BACKGROUND: Lenvatinib plus pembrolizumab showed significantly improved progression-free and overall survival outcomes compared with sunitinib in patients with advanced renal cell carcinoma in the CLEAR study (NCT02811861). Here, we used CLEAR data to characterize common adverse reactions (ARs; adverse-event preferred terms grouped in accordance with regulatory authority review) associated with lenvatinib plus pembrolizumab and review management strategies for select ARs. MATERIALS AND METHODS: Safety data from the 352 patients who received lenvatinib plus pembrolizumab in the CLEAR study were analyzed. Key ARs were chosen based on frequency of occurrence (≥30%). Time to first onset and management strategies for key ARs were detailed. RESULTS: The most frequent ARs were fatigue (63.1%), diarrhea (61.9%), musculoskeletal pain (58.0%), hypothyroidism (56.8%), and hypertension (56.3%); grade ≥3 severity ARs that occurred in ≥5% of patients were hypertension (28.7%), diarrhea (9.9%), fatigue (9.4%), weight decreased (8.0%), and proteinuria (7.7%). Median times to first onset of all key ARs were within approximately 5 months (approximately 20 weeks) of starting treatment. Strategies for effectively managing ARs included baseline monitoring, drug-dose modifications, and/or concomitant medications. CONCLUSION: The safety profile of lenvatinib plus pembrolizumab was consistent with the known profile of each monotherapy; ARs were considered manageable with strategies including monitoring, dose modifications, and supportive medications. Proactive and prompt identification and management of ARs are important for patient safety and to support continued treatment. CLINICALTRIALS.GOV ID: NCT02811861.
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Carcinoma de Células Renales , Hipertensión , Neoplasias Renales , Humanos , Carcinoma de Células Renales/patología , Compuestos de Fenilurea/efectos adversos , Neoplasias Renales/patología , Fatiga/inducido químicamente , Diarrea/inducido químicamente , Hipertensión/inducido químicamente , Hipertensión/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéuticoRESUMEN
Glycosylation in live cell and animal modulate a constellation of biological functions. The advent of Chemical Biology has revolutionized the analysis and tailoring of glycans, by introducing myriads of glycan engineering methods. However, the ideal scenario to achieve glycan monitoring and structural manipulation at any hierarchical levels is unmet yet. Herein we review recent advances in the methodological innovation and the versatile applications of the protein-specific glycan visualization and editing in deciphering the biological functions of glycans. An outlook for future directions toward specific sugar-chain editing is also included.
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Polisacáridos , Azúcares , Animales , Glicosilación , Polisacáridos/químicaRESUMEN
Object recognition relies on a multitude of factors, including size, orientation, and so on. Mirrored orientation, particularly due to children's mirror confusion in reading, holds special significance among various object orientations. Brain imaging studies suggest that the visual ventral and dorsal streams exhibit distinct orientation sensitivity across diverse object categories. Yet, it remains unclear whether mirror orientation sensitivity also varies among these categories during development at the behavioral level. Here, we explored the mirror sensitivity of children and adults across five distinct categories, which encompass tools that activate both the visual ventral stream for function information and the dorsal stream for manipulation information, and animals and faces that mainly activate the ventral stream. Two types of symbols, letters and Chinese characters, were also included. Mirror sensitivity was assessed through mirror costs-that is, the additional reaction time or error rate in the mirrored versus the same orientation condition when judging the identity of object pairs. The mirror costs in reaction times and error rates consistently revealed that children exhibited null mirror costs for tools, and the mirror costs for tools in adults were minimal, if any, and were smaller than those for letters and characters. The mirror costs reflected in absolute reaction time and error rate were similar across adults and children, but when the overall difference in reaction times was considered, adults showed a larger mirror cost than children. Overall, our investigation unveils categorical distinctions and development in mirror sensitivity of object recognition across the ventral and dorsal streams.
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Imagen por Resonancia Magnética , Reconocimiento Visual de Modelos , Humanos , Adulto , Niño , Reconocimiento Visual de Modelos/fisiología , Percepción Visual/fisiología , Encéfalo/fisiología , Tiempo de Reacción/fisiologíaRESUMEN
The immobilization of proteins on nanoparticles has received much attention in recent years. Among different approaches, enzymatic protein immobilization shows unique advantages because of its site-specific connection. OaAEP1 is a recently engineered peptide ligase which can specifically recognize an N-terminal GL residue (NH2-Gly-Leu) and a C-terminal NGL amino acid residue (Asn-Gly-Leu-COOH) and ligates them efficiently. Herein, we report OaAEP1-mediated protein immobilization on synthetic magnetic nanoparticles. Our work showed that OaAEP1 could mediate C-terminal site-specific protein immobilization on the amino-functionalized Fe3O4 nanoparticles. Our work demonstrates a new method for site-specific protein immobilization on nanoparticles.
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Enzimas Inmovilizadas , Enzimas Inmovilizadas/químicaRESUMEN
Site-specific functionalization of natural amino acid-containing biological nanopores is pivotal in single molecule sensing. However, pore engineering methodologies are restricted to a limited choice and introduction of unnatural chemical components is extremely difficult. Herein we report the genetic code expansion (GCE) strategy to introduce unnatural amino acid (UAA) to an octameric Mycobacterium smegmatis porin A (MspA) nanopore. GCE allows for rapid and efficient introduction of bioorthogonal reactive site (i.e., azide) to the pore rim, and conjugation of single stranded DNA or lysozyme was demonstrated. The lysozyme-conjugated pore was further used for the discrimination of different oligosaccharides, demonstrating a sensing capacity that a bare MspA nanopore does not possess. GCE with bioorthogonal handles, which has never been previously applied in the preparation of nanopores, is a versatile strategy for pore engineering and may further expand the application scenarios of nanopores.
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Nanoporos , Muramidasa/genética , Muramidasa/metabolismo , ADN de Cadena Simple , Código Genético , Porinas/metabolismo , Mycobacterium smegmatis/químicaRESUMEN
Whispering-gallery-mode (WGM) microcavities have shown significant applications in nanoparticle sensing for environmental monitoring and biological analysis. However, the enhancement of detection resolution often calls for active cavities or elaborate structural designs, leading to an increase of fabrication complexity and cost. Herein, heterodyne amplification is implemented in WGM microsensors based on backscattering detection mechanism. By interfering with an exotic reference laser, the reflecting light backscattered by perturbation targets can be strongly enlarged, yielding an easy-to-resolve and consequently sensitive microsensor. The dependence of detection laser frequency has also been characterized with the assistance of optothermal dynamics. We show that exploiting heterodyne interferometry boosts the detection of weak signals in microresonator systems and provides a fertile ground for optical microsensor development.
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NanopartículasRESUMEN
Cannabidiol is the main non-psychoactive component of Cannabis sativa, which has multiple medicinal activities, such as antiepileptic, immunomodulation, analgesic, antioxidant, anticonvulsant, anti-anxiety and other functions. In recent years, it has been found that cannabidiol can inhibit the proliferation of various tumor cells, induce apoptosis and autophagy of tumor cells, arrest cell cycle, interrupt invasion and metastasis of tumor cells, regulate tumor microenvironment, exert synergistic therapy with other chemotherapeutic drugs, and reduce the toxicity of chemotherapeutic drugs. However, its anti-tumor effect remains controversial and its application is limited. The study of microspheres, nano liposomes and other new drug delivery systems can improve the anti-tumor effect of cannabidiol. In this study, the anti-tumor mechanism and application of cannabidiol were summarized and discussed in order to provide inspirations for its further investigation and application.
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Cannabidiol , Cannabis , Neoplasias , Humanos , Cannabidiol/farmacología , Cannabidiol/uso terapéutico , Neoplasias/tratamiento farmacológico , Apoptosis , Trastornos de Ansiedad/tratamiento farmacológico , Microambiente TumoralRESUMEN
We report a novel, to the best of our knowledge, way to achieve phase-controlled dual-wavelength resonance based on whispering-gallery-mode (WGM) microcavities experimentally. With the help of a feedback waveguide, not only two optical pathways but also a unidirectional coupling between counter-propagating waves are formed, which is the requirement of all-optical analogues of electromagnetically induced transparency and Autler-Townes splitting. By adjusting the accumulating phase introduced from the fiber waveguide, we observe the signal lineshape changes from symmetric to asymmetric, i.e., the resonant transmission and extinction ratio of two splitting modes can be controlled, which brings a new degree of freedom to the WGM resonator system. These results may boost the development of quantum state control and pave the way for reconfiguring devices such as narrow-band filters.
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Traditional Chinese multi-herb-combined prescriptions usually show better performance than a single agent since a group of effective compounds interfere multiple disease-relevant targets simultaneously. Huang-Lian-Jie-Du decoction is a remedy made of four herbs that are widely used to treat oral ulcers, gingivitis, and periodontitis. However, the active ingredients and underlying mechanisms are not clear. To address these questions, we prepared a water extract solution of Huang-Lian-Jie-Du decoction (HLJDD), called it as WEH (Water Extract Solution of HLJDD), and used it to treat LPS-induced systemic inflammation in mice. We observed that WEH attenuated inï¬ammatory responses including reducing production of cytokines, chemokines and interferons (IFNs), further attenuating emergency myelopoiesis, and preventing mice septic lethality. Upon LPS stimulation, mice pretreated with WEH increased circulating Ly6C- patrolling and splenic Ly6C+ inflammatory monocytes. The acute myelopoiesis related transcriptional factor profile was rearranged by WEH. Mechanistically we confirmed that WEH interrupted LPS/TLR4/CD14 signaling-mediated downstream signaling pathways through its nine principal ingredients, which blocked LPS stimulated divergent signaling cascades, such as activation of NF-κB, p38 MAPK, and ERK1/2. We conclude that the old remedy blunts LPS-induced "danger" signal recognition and transduction process at multiple sites. To translate our findings into clinical applications, we refined the crude extract into a pure multicomponent drug by directly mixing these nine chemical entities, which completely reproduced the effect of protecting mice from lethal septic shock. Finally, we reduced a large number of compounds within a multi-herb water extract to seven-chemical combination that exhibited superior therapeutic efficacy compared with WEH.
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Medicamentos Herbarios Chinos/uso terapéutico , Inflamación/tratamiento farmacológico , Monocitos/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Factores de Transcripción/efectos de los fármacos , Animales , Reprogramación Celular/efectos de los fármacos , Coptis chinensis , Medicamentos Herbarios Chinos/administración & dosificación , Citometría de Flujo , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Extractos Vegetales/administración & dosificación , Células RAW 264.7/efectos de los fármacos , Factores de Transcripción/metabolismoRESUMEN
Mammalian brains are highly enriched with sialoglycans, which have been implicated in brain development and disease progression. However, in vivo labeling and visualization of sialoglycans in the mouse brain remain a challenge because of the blood-brain barrier. Here we introduce a liposome-assisted bioorthogonal reporter (LABOR) strategy for shuttling 9-azido sialic acid (9AzSia), a sialic acid reporter, into the brain to metabolically label sialoglycoconjugates, including sialylated glycoproteins and glycolipids. Subsequent bioorthogonal conjugation of the incorporated 9AzSia with fluorescent probes via click chemistry enabled fluorescence imaging of brain sialoglycans in living animals and in brain sections. Newly synthesized sialoglycans were found to widely distribute on neuronal cell surfaces, in particular at synaptic sites. Furthermore, large-scale proteomic profiling identified 140 brain sialylated glycoproteins, including a wealth of synapse-associated proteins. Finally, by performing a pulse-chase experiment, we showed that dynamic sialylation is spatially regulated, and that turnover of sialoglycans in the hippocampus is significantly slower than that in other brain regions. The LABOR strategy provides a means to directly visualize and monitor the sialoglycan biosynthesis in the mouse brain and will facilitate elucidating the functional role of brain sialylation.
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Encéfalo/metabolismo , Genes Reporteros/fisiología , Liposomas/química , Imagen Molecular/métodos , Polisacáridos/metabolismo , Ácidos Siálicos/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente/métodos , Proteínas Recombinantes/metabolismo , Coloración y Etiquetado/métodos , Distribución TisularRESUMEN
Docetaxel-loaded nanomicelles were prepared in this study to improve the solubility and tumor targeting effect of docetaxel(DTX),and further evaluate their anticancer effects in vitro. PBAE-DTX nanomicelles were prepared by film-hydration method with amphiphilic block copolymer polyethyleneglycol methoxy-polylactide(PELA) and pH sensitive triblock copolymer polyethyleneglycol methoxy-polylactide-poly-ß-aminoester(PBAE) were used respectively to prepare PELA-DTX nanomicelles and PBAE-DTX nanomicelles. The nanomicelles were characterized by physicochemical properties and the activity of mice Lewis lung cancer cells was studied. The results of particle size measurement showed that the blank micelles and drug-loaded micelles had similar particle sizes, ranging from 10 to 100 nm. The particle size of PBAE micelles was changed under weak acidic conditions, with good pH response. The encapsulation efficiency of the above two types of DTX-loaded nanomicelles determined by HPLC was(93.8±1.70)% and(87.2±4.10)%, and the drug loading amount was(5.3±0.10)% and(4.9±0.05)%,respectively. Furthermore,the DTX micelles also showed significant inhibitory effects on Lewis lung cancer cells by MTT assay, and pH-sensitive PBAE-DTX showed better cytotoxicity. The results of flow cytometry indicated that,the apoptosis rate of lung cancer Lewis cells was(20.72±1.47)%,(29.71±2.38)%,and(40.91±1.90)%(P<0.05) at 48 h after treatment in DTX,PELA-DTX,and PBAE-DTX groups. The results showed that different docetaxel preparations could promote the apoptosis of Lewis cells, and PBAE-DTX had stronger apoptotic-promoting effect. The pH-sensitive DTX-loaded micelles are promising candidates in developing stimuli triggered drug delivery systems in acidic tumor micro-environments with improved inhibitory effects of tumor growth on Lewis lung cancer.