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1.
Org Biomol Chem ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38606462

RESUMO

A method for generation of SVI sulfones from ß-sulfinyl esters (SIV) under transition-metal-free non-oxidative mild conditions is presented. Various sulfones have been achieved with moderate to excellent yields. The advantage of using ß-sulfinyl esters as masked aryl sulfinates has also been exemplified using brominated substrates. Oxygen isotope-labeling experiments indicated that the oxygen atoms incorporated into the sulfone product come from the sulfoxide of the ß-sulfinyl ester. Successive ß-elimination/O-addition/sulfinate esterification/ß-elimination processes are proposed for the mechanism of generating SVI from SIV.

2.
Methods ; 226: 9-18, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604412

RESUMO

Biomedical event extraction is an information extraction task to obtain events from biomedical text, whose targets include the type, the trigger, and the respective arguments involved in an event. Traditional biomedical event extraction usually adopts a pipelined approach, which contains trigger identification, argument role recognition, and finally event construction either using specific rules or by machine learning. In this paper, we propose an n-ary relation extraction method based on the BERT pre-training model to construct Binding events, in order to capture the semantic information about an event's context and its participants. The experimental results show that our method achieves promising results on the GE11 and GE13 corpora of the BioNLP shared task with F1 scores of 63.14% and 59.40%, respectively. It demonstrates that by significantly improving the performance of Binding events, the overall performance of the pipelined event extraction approach or even exceeds those of current joint learning methods.

3.
J Cancer Res Clin Oncol ; 150(4): 193, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619663

RESUMO

PURPOSE: Minimal residual disease (MRD) is a validated prognostic factor in several hematological malignancies. However, its role in systemic light chain (AL) amyloidosis remains controversial, and this systematic review and meta-analysis aims to fill this gap. METHODS: We searched for relevant studies on Pubmed, Embase, and Cochrane Controlled Register of Trials, nine studies involving 451 patients were included and meta-analyzed. This systematic review has been registered in PROSPERO (CRD42023494169). RESULTS: Our study found that in the group of patients who achieved very good partial response (VGPR) or better, MRD negativity was correlated with higher cardiac and renal response rates [pooled risk ratio (RR) = 0.74 (95% CI 0.62-0.89), 0.74 (95% CI 0.64-0.87), respectively]. Patients with MRD positivity had a higher hematologic progression rate within two years after MRD detection [pooled RR = 10.31 (95% CI 2.02-52.68)]; and a higher risk of hematologic + organ progression in the first year [pooled RR = 12.57 (95% CI 1.73-91.04)]. Moreover, MRD negativity was correlated with a better progression-free survival (PFS) [pooled hazard ratio (HR) = 0.27 (95% CI 0.17-0.45)]; but it did not significantly improve the overall survival (OS) [pooled HR = 0.34 (95% CI 0.11-1.07)]. CONCLUSION: In AL amyloidosis, our study supports that MRD negativity correlates with higher cardiac or renal response rates and indicates a better PFS in the follow-up. However, the correlation between OS and the status of MRD is not significant.


Assuntos
Amiloidose , Neoplasias Hematológicas , Amiloidose de Cadeia Leve de Imunoglobulina , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/terapia , Neoplasia Residual , Rim
4.
Nat Biomed Eng ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641710

RESUMO

Intracellular DNA sensors regulate innate immunity and can provide a bridge to adaptive immunogenicity. However, the activation of the sensors in antigen-presenting cells (APCs) by natural agonists such as double-stranded DNAs or cyclic nucleotides is impeded by poor intracellular delivery, serum stability, enzymatic degradation and rapid systemic clearance. Here we show that the hydrophobicity, electrostatic charge and secondary conformation of helical polypeptides can be optimized to stimulate innate immune pathways via endoplasmic reticulum stress in APCs. One of the three polypeptides that we engineered activated two major intracellular DNA-sensing pathways (cGAS-STING (for cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes) and Toll-like receptor 9) preferentially in APCs by promoting the release of mitochondrial DNA, which led to the efficient priming of effector T cells. In syngeneic mouse models of locally advanced and metastatic breast cancers, the polypeptides led to potent DNA-sensor-mediated antitumour responses when intravenously given as monotherapy or with immune checkpoint inhibitors. The activation of multiple innate immune pathways via engineered cationic polypeptides may offer therapeutic advantages in the generation of antitumour immune responses.

5.
Nat Commun ; 15(1): 2672, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531889

RESUMO

Selective ion transport underpins fundamental biological processes for efficient energy conversion and signal propagation. Mimicking these 'ionics' in synthetic nanofluidic channels has been increasingly promising for realizing self-sustained systems by harvesting clean energy from diverse environments, such as light, moisture, salinity gradient, etc. Here, we report a spatially nanoconfined ion separation strategy that enables harvesting electricity from CO2 adsorption. This breakthrough relies on the development of Nanosheet-Agarose Hydrogel (NAH) composite-based generators, wherein the oppositely charged ions are released in water-filled hydrogel channels upon adsorbing CO2. By tuning the ion size and ion-channel interactions, the released cations at the hundred-nanometer scale are spatially confined within the hydrogel network, while ångström-scale anions pass through unhindered. This leads to near-perfect anion/cation separation across the generator with a selectivity (D-/D+) of up to 1.8 × 106, allowing conversion into external electricity. With amplification by connecting multiple as-designed generators, the ion separation-induced electricity reaching 5 V is used to power electronic devices. This study introduces an effective spatial nanoconfinement strategy for widely demanded high-precision ion separation, encouraging a carbon-negative technique with simultaneous CO2 adsorption and energy generation.

6.
Sci Rep ; 14(1): 6110, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480753

RESUMO

To verify the novel method of achieving a true-triaxial stress path with the pseudo-triaxial apparatus, a series of drained and undrained tests were carried out for the identical scheme with pseudo-triaxial apparatus and true-triaxial apparatus respectively. The differences between the two types of tests were quantified. The results show that the novel method effectively achieved the true-triaxial stress path by controlling the loading ratio of the pseudo-triaxial apparatus. The relationships of q - Îµ1 and η - Îµs measured by the two apparatuses had a higher similarity which decreases slightly with the b increase. When 0 ≤ b < 0.5, the slope of the critical state line measured by both apparatuses was almost identical. When 0.5 ≤ b ≤ 1, the slope of the critical state line measured by the novel method was slightly lower, but the biggest change was within 10% compared with the two Mohr-Coulomb criteria, the peak strength measured by the two apparatuses was distributed near the criteria, indicating the feasibility and rationality of the novel method. The tests show that the novel method greatly enriches the test range of pseudo-triaxial apparatus, which not only simplifies the process of soil 3D testing but also reduces the test cost.

7.
Org Lett ; 26(11): 2152-2157, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38456394

RESUMO

An asymmetric Michael/Friedel-Crafts cascade reaction with Morita-Baylis-Hillman (MBH) nitroallylic esters and 3-pyrrolyloxindoles has been developed for the stereoselective construction of spirooxindole-containing tetrahydroindolizines. A range of tetracyclic scaffolds possessing three consecutive chiral centers, including an all-carbon quaternary stereocenter, were generated in 53-85% isolated yields with high diastereoselectivities and enantiopurities (≥3:1 dr, 50-98% ee). A newly synthesized bifunctional secondary amine/squaramide organocatalyst was demonstrated to exhibit better stereochemical control than their tertiary analogues.

8.
Heliyon ; 10(6): e28295, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38545181

RESUMO

Sunitinib, the first-line targeted therapy for metastatic clear cell renal cell carcinoma (ccRCC), faces a significant challenge as most patients develop acquired resistance. Integrated genomic and proteomic analyses identified PYGL as a novel therapeutic target for ccRCC. PYGL knockdown inhibited cell proliferation, cloning capacity, migration, invasion, and tumorigenesis in ccRCC cell lines. PYGL expression was increased in sunitinib-resistant ccRCC cell lines, and CP-91149 targeting the PYGL could restore drug sensitivity in these cell lines. Moreover, chromatin immune-precipitation assays revealed that PYGL upregulation is induced by the transcription factor, hypoxia-inducible factor 1α. Overall, PYGL was identified as a novel diagnostic biomarker by combining genomic and proteomic approaches in ccRCC, and sunitinib resistance to ccRCC may be overcome by targeting PYGL.

9.
Hepatol Res ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430513

RESUMO

BACKGROUND AND AIM: Autotaxin (ATX) is an extracellular lysophospholipase D that catalyzes the hydrolysis of lysophosphatidylcholine into lysophosphatidic acid (LPA). Recent accumulating evidence indicates the biological roles of ATX in malignant tumors. However, the expression and clinical implications of ATX in human cholangiocarcinoma (CCA) remain elusive. METHODS: In this study, the expression of ATX in 97 human CCA tissues was evaluated by immunohistochemistry. Serum ATX levels were determined in CCA patients (n = 26) and healthy subjects (n = 8). Autotaxin expression in cell types within the tumor microenvironment was characterized by immunofluorescence staining. RESULTS: High ATX expression in CCA tissue was significantly associated with a higher frequency of lymph node metastasis (p = 0.050). High ATX expression was correlated with shorter overall survival (p = 0.032) and recurrence-free survival (RFS) (p = 0.001) than low ATX expression. In multivariate Cox analysis, high ATX expression (p = 0.019) was an independent factor for shorter RFS. Compared with low ATX expression, high ATX expression was significantly associated with higher Ki-67-positive cell counts (p < 0.001). Serum ATX levels were significantly higher in male CCA patients than in healthy male subjects (p = 0.030). In the tumor microenvironment of CCA, ATX protein was predominantly expressed in tumor cells, cancer-associated fibroblasts, plasma cells, and biliary epithelial cells. CONCLUSIONS: Our study highlights the clinical evidence and independent prognostic value of ATX in human CCA.

10.
Appl Microbiol Biotechnol ; 108(1): 238, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407600

RESUMO

Pasteurella multocida is an important bacterial pathogen that can cause diseases in both animals and humans. Its elevated morbidity and mortality rates in animals result in substantial economic repercussions within the livestock industry. The prevention of diseases caused by P. multocida through immunization is impeded by the absence of a safe and effective vaccine. Outer membrane vesicles (OMVs) secreted from the outer membrane of Gram-negative bacteria are spherical vesicular structures that encompass an array of periplasmic components in conjunction with a diverse assortment of lipids and proteins. These vesicles can induce antibacterial immune responses within the host. P. multocida has been shown to produce OMVs. Nonetheless, the precise characteristics and immunomodulatory functions of P. multocida OMVs have not been fully elucidated. In this study, OMVs were isolated from P. multocida using an ultrafiltration concentration technique, and their morphology, protein constitution, and immunomodulatory properties in RAW264.7 cells were studied. Transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA) revealed that the OMVs exhibited typical spherical and bilayered lipid vesicular architecture, exhibiting an average diameter of approximately 147.5 nm. The yield of OMVs was 2.6 × 1011 particles/mL. Proteomic analysis revealed a high abundance of membrane-associated proteins within P. multocida OMVs, with the capability to instigate the host's immune response. Furthermore, OMVs stimulated the proliferation and cellular uptake of macrophages and triggered the secretion of cytokines, such as TNF-ɑ, IL-1ß, IL-6, IL-10, and TGF-ß1. Consequently, our results indicated that OMVs from P. multocida could directly interact with macrophages and regulate their immune function in vitro. These results supported the prospective applicability of P. multocida OMVs as a platform in the context of vaccine development. KEY POINTS: • Preparation and characterization of P. multocida OMVs. • P. multocida OMVs possess a range of antigens and lipoproteins associated with the activation of the immune system. • P. multocida OMVs can activate the proliferation, internalization, and cytokine secretion of macrophages in vitro.


Assuntos
Pasteurella multocida , Animais , Humanos , Estudos Prospectivos , Proteômica , Macrófagos , Periplasma
11.
Bioact Mater ; 35: 208-227, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38327823

RESUMO

Repair of large bone defects caused by severe trauma, non-union fractures, or tumor resection remains challenging because of limited regenerative ability. Typically, these defects heal through mixed routines, including intramembranous ossification (IMO) and endochondral ossification (ECO), with ECO considered more efficient. Current strategies to promote large bone healing via ECO are unstable and require high-dose growth factors or complex cell therapy that cause side effects and raise expense while providing only limited benefit. Herein, we report a bio-integrated scaffold capable of initiating an early hypoxia microenvironment with controllable release of low-dose recombinant bone morphogenetic protein-2 (rhBMP-2), aiming to induce ECO-dominated repair. Specifically, we apply a mesoporous structure to accelerate iron chelation, this promoting early chondrogenesis via deferoxamine (DFO)-induced hypoxia-inducible factor-1α (HIF-1α). Through the delicate segmentation of click-crosslinked PEGylated Poly (glycerol sebacate) (PEGS) layers, we achieve programmed release of low-dose rhBMP-2, which can facilitate cartilage-to-bone transformation while reducing side effect risks. We demonstrate this system can strengthen the ECO healing and convert mixed or mixed or IMO-guided routes to ECO-dominated approach in large-size models with clinical relevance. Collectively, these findings demonstrate a biomaterial-based strategy for driving ECO-dominated healing, paving a promising pave towards its clinical use in addressing large bone defects.

12.
Can Assoc Radiol J ; : 8465371241231573, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389194

RESUMO

Purpose: To determine whether multiparametric MRI-based spatial habitats and fractal analysis can help distinguish triple-negative breast cancer (TNBC) from non-TNBC. Method: Multiparametric DWI and DCE-MRI at 3T were obtained from 142 biopsy- and surgery-proven breast cancer with 148 breast lesions (TNBC = 26 and non-TNBC = 122). The contrast-enhancing lesions were divided into 3 spatial habitats based on perfusion and diffusion patterns using K-means clustering. The fractal dimension (FD) of the tumour subregions was calculated. The accuracy of the habitat segmentation was measured using the Dice index. Inter- and intra-reader reliability were evaluated with the intraclass correlation coefficient (ICC). The ability to predict TNBC status was assessed using the receiver operating characteristic curve. Results: The Dice index for the whole tumour was 0.81 for inter-reader and 0.88 for intra-reader reliability. The inter- and intra-reader reliability were excellent for all 3 tumour habitats and fractal features (ICC > 0.9). TNBC had a lower hypervascular cellular habitat and higher FD 1 compared to non-TNBC (all P < .001). Multivariate analysis confirmed that hypervascular cellular habitat (OR = 0.88) and FD 1 (OR = 1.35) were independently associated with TNBC (all P < .001) after adjusting for rim enhancement, axillary lymph nodes status, and histological grade. The diagnostic model combining hypervascular cellular habitat and FD 1 showed excellent discriminatory ability for TNBC, with an AUC of 0.951 and an accuracy of 91.9%. Conclusions: The fraction of hypervascular cellular habitat and its FD may serve as useful imaging biomarkers for predicting TNBC status.

13.
Front Aging Neurosci ; 16: 1335550, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298610

RESUMO

Non-motor symptoms are prevalent among individuals with Parkinson's disease (PD) and seriously affect patient quality of life, even more so than motor symptoms. In the past decade, an increasing number of studies have investigated non-motor symptoms in PD. The present study aimed to comprehensively analyze the global literature, trends, and hotspots of research investigating non-motor symptoms in PD through bibliometric methods. Studies addressing non-motor symptoms in the Web of Science Core Collection (WoSCC), published between January 2013 and December 2022, were retrieved. Bibliometric methods, including the R package "Bibliometrix," VOS viewer, and CiteSpace software, were used to investigate and visualize parameters, including yearly publications, country/region, institution, and authors, to collate and quantify information. Analysis of keywords and co-cited references explored trends and hotspots. There was a significant increase in the number of publications addressing the non-motor symptoms of PD, with a total of 3,521 articles retrieved. The United States was ranked first in terms of publications (n = 763) and citations (n = 11,269), maintaining its leadership position among all countries. King's College London (United Kingdom) was the most active institution among all publications (n = 133) and K Ray Chaudhuri was the author with the most publications (n = 131). Parkinsonism & Related Disorders published the most articles, while Movement Disorders was the most cited journal. Reference explosions have shown that early diagnosis, biomarkers, novel magnetic resonance imaging techniques, and deep brain stimulation have become research "hotspots" in recent years. Keyword clustering revealed that alpha-synuclein is the largest cluster for PD. The keyword heatmap revealed that non-motor symptoms appeared most frequently (n = 1,104), followed by quality of life (n = 502), dementia (n = 403), and depression (n = 397). Results of the present study provide an objective, comprehensive, and systematic analysis of these publications, and identifies trends and "hot" developments in this field of research. This work will inform investigators worldwide to help them conduct further research and develop new therapies.

14.
Free Radic Biol Med ; 212: 403-414, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38171408

RESUMO

Bone remodeling is essential for the repair and replacement of damaged or aging bones. Continuous remodeling is necessary to prevent the accumulation of bone damage and to maintain bone strength and calcium balance. As bones age, the coupling mechanism between bone formation and absorption becomes dysregulated, and bone loss becomes dominant. Bone development and repair rely on interaction and communication between osteoclasts and surrounding cells. Osteoclasts are specialized cells that are accountable for bone resorption and degradation, and any abnormalities in their activity can result in notable alterations in bone structure and worsen disease symptoms. Recent findings from transgenic mouse models and bone analysis have greatly enhanced our understanding of the origin, differentiation pathway, and activation stages of osteoclasts. In this review, we explore osteoclasts and discuss the cellular and molecular events that drive their generation, focusing on intracellular oxidative and antioxidant signaling. This knowledge can help develop targeted therapies for diseases associated with osteoclast activation.


Assuntos
Reabsorção Óssea , Osteoclastos , Camundongos , Animais , Osteoclastos/metabolismo , Antioxidantes/metabolismo , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Osso e Ossos/metabolismo , Diferenciação Celular , Camundongos Transgênicos , Oxirredução
15.
J Neurosurg Spine ; 40(2): 255-264, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37948696

RESUMO

OBJECTIVE: The objective of this study was to evaluate the factors that affect refracture in the same cemented vertebra after percutaneous kyphoplasty (PKP) for Kümmell's disease (KD) and establish a risk prediction score. METHODS: A total of 2932 patients who were treated with PKP for KD between January 2019 and December 2021 were retrospectively reviewed. After inclusion and exclusion criteria were applied, 191 patients were included in the study. According to the criteria for refracture, there were 50 patients in the refracture group and 141 patients in the no-refracture group. Twenty-five factors were analyzed. Patient demographics, medical history, imaging data, surgical data, and postoperative management were reviewed. Multivariate logistic regression modeling was used to identify the independent risk factors for refracture. Receiver operating characteristic (ROC) curve analysis was used to assess and establish a risk score system and further predict the risk of refracture. RESULTS: In this study, 50 (26.2%) patients developed a refracture. Through univariate analysis, bone mineral density (BMD) (p < 0.001), compression rate (p = 0.007), classification (i.e., the stages determined by the compression ratios) (p < 0.001), bone cement volume (p < 0.001), volume fraction (p < 0.001), distribution pattern (p = 0.007), non-PMMA endplate contact (p < 0.001), and anti-osteoporosis therapy (p < 0.001) were found to be significant factors for post-cement vertebral refracture after PKP in patients with KD. Three independent risk factors were found to be significant for refracture: small volume fraction, low BMD, and no anti-osteoporosis therapy. One point was assigned for each factor. The incidence rates of refracture in patients with scores of 0, 1, 2, and 3 were 3.7%, 4.4%, 42.0%, and 100%, respectively. The area under the ROC curve for this risk prediction score was 0.888 (p < 0.001), indicating moderate accuracy. CONCLUSIONS: Volume fraction, BMD, and osteoporosis therapy are the main factors influencing the refracture of the same cemented vertebra in KD. On the basis of these factors, the risk prediction score developed in this paper can be used to forecast the incidence of refracture.


Assuntos
Fraturas por Compressão , Cifoplastia , Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Espondilose , Humanos , Cifoplastia/efeitos adversos , Cifoplastia/métodos , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas por Compressão/cirurgia , Resultado do Tratamento , Coluna Vertebral , Osteoporose/epidemiologia , Cimentos Ósseos/efeitos adversos , Fatores de Risco , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/cirurgia
16.
Mol Cancer Ther ; 23(3): 330-342, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-37956421

RESUMO

Ionizing radiation is known to possess immune modulatory properties. However, how radiotherapy (RT) may complement with different types of immunotherapies to boost antitumor responses is unclear. In mice implanted with EO771 syngeneic tumors, NL-201 a stable, highly potent CD25-independent agonist to IL2 and IL15 receptors with enhanced affinity for IL2Rßγ was given with or without RT. Flow analysis and Western blot analysis was performed to determine the mechanisms involved. STING (-/-) and CD11c+ knockout mice were implanted with EO771 tumors to confirm the essential signaling and cell types required to mediate the effects seen. Combination of RT and NL-201 to enhance systemic immunotherapy with an anti-PD-1 checkpoint inhibitor was utilized to determine tumor growth inhibition and survival, along characterization of tumor microenvironment as compared with all other treatment groups. Here, we showed that RT, synergizing with NL-201 produced enhanced antitumor immune responses in murine breast cancer models. When given together, RT and NL-201 enhanced activation of the cytosolic DNA sensor cyclic GMP-AMP synthase-stimulator of IFN genes (cGAS-STING) pathway, resulting in increased type I IFN production in dendritic cells (DC), and consequently greater tumor infiltration and more efficient priming of antigen-specific T cells. The immune stimulatory mechanisms triggered by NL-201 and RT resulted in superior tumor growth inhibition and survival benefit in both localized and metastatic cancers. Our results support further preclinical and clinical investigation of this novel synergism regimen in locally advanced and metastatic settings.


Assuntos
Interleucina-15 , Neoplasias , Animais , Camundongos , Interleucina-2 , Neoplasias/radioterapia , Linfócitos T , Imunidade Inata , Microambiente Tumoral
17.
Life Sci ; 336: 122319, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38035993

RESUMO

Various strategies can be employed to prevent and manage altitude illnesses, including habituation, oxygenation, nutritional support, and medication. Nevertheless, the utilization of drugs for the prevention and treatment of hypoxia is accompanied by certain adverse effects. Consequently, the quest for medications that exhibit minimal side effects while demonstrating high efficacy remains a prominent area of research. In this context, it is noteworthy that free radical scavengers exhibit remarkable anti-hypoxia activity. These scavengers effectively eliminate excessive free radicals and mitigate the production of reactive oxygen species (ROS), thereby safeguarding the body against oxidative damage induced by plateau hypoxia. In this review, we aim to elucidate the pathogenesis of plateau diseases that are triggered by hypoxia-induced oxidative stress at high altitudes. Additionally, we present a range of free radical scavengers as potential therapeutic and preventive approaches to mitigate the occurrence of common diseases associated with hypoxia at high altitudes.


Assuntos
Doença da Altitude , Sequestradores de Radicais Livres , Humanos , Sequestradores de Radicais Livres/farmacologia , Doença da Altitude/tratamento farmacológico , Altitude , Estresse Oxidativo , Hipóxia/tratamento farmacológico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico
18.
Nat Nanotechnol ; 19(2): 255-263, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37723279

RESUMO

Nanomedicines have been approved to treat multiple human diseases. However, clinical adoption of nanoformulated agents is often hindered by concerns about hepatic uptake and clearance, a process that is not fully understood. Here we show that the antitumour efficacy of cancer nanomedicine exhibits an age-associated disparity. Tumour delivery and treatment outcomes are superior in old versus young mice, probably due to an age-related decline in the ability of hepatic phagocytes to take up and remove nanoparticles. Transcriptomic- and protein-level analysis at the single-cell and bulk levels reveals an age-associated decrease in the numbers of hepatic macrophages that express the scavenger receptor MARCO in mice, non-human primates and humans. Therapeutic blockade of MARCO is shown to decrease the phagocytic uptake of nanoparticles and improve the antitumour effect of clinically approved cancer nanotherapeutics in young but not aged mice. Together, these results reveal an age-associated disparity in the phagocytic clearance of nanotherapeutics that affects their antitumour response, thus providing a strong rationale for an age-appropriate approach to cancer nanomedicine.


Assuntos
Nanopartículas , Neoplasias , Humanos , Camundongos , Animais , Neoplasias/terapia , Fagócitos/patologia , Nanomedicina/métodos , Nanopartículas/uso terapêutico , Cinética
19.
Adv Sci (Weinh) ; 11(3): e2304648, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38037457

RESUMO

The balance among different CD4+ T cell subsets is crucial for repairing the injured spinal cord. Dendritic cell (DC)-derived small extracellular vesicles (DsEVs) effectively activate T-cell immunity. Altered peptide ligands (APLs), derived from myelin basic protein (MBP), have been shown to affect CD4+ T cell subsets and reduce neuroinflammation levels. However, the application of APLs is challenging because of their poor stability and associated side effects. Herein, it is demonstrate that DsEVs can act as carriers for APL MBP87-99 A91 (A91-DsEVs) to induce the activation of 2 helper T (Th2) and regulatory T (Treg) cells for spinal cord injury (SCI) in mice. These stimulated CD4+ T cells can efficiently "home" to the lesion area and establish a beneficial microenvironment through inducing the activation of M2 macrophages/microglia, inhibiting the expression of inflammatory cytokines, and increasing the release of neurotrophic factors. The microenvironment mediated by A91-DsEVs may enhance axon regrowth, protect neurons, and promote remyelination, which may support the recovery of motor function in the SCI model mice. In conclusion, using A91-DsEVs as a therapeutic vaccine may help induce neuroprotective immunity in the treatment of SCI.


Assuntos
Vesículas Extracelulares , Traumatismos da Medula Espinal , Vacinas , Ratos , Camundongos , Animais , Ratos Sprague-Dawley , Ligantes , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/metabolismo , Vacinas/farmacologia , Vacinas/uso terapêutico , Peptídeos , Linfócitos T Reguladores , Vesículas Extracelulares/metabolismo , Células Dendríticas
20.
J Org Chem ; 89(1): 452-462, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38085572

RESUMO

A [2 + 4]/[1 + 2] annulation approach was successfully established to construct pyrroloquinoline-fused cyclopropane in a highly diastereoselective fashion (>20:1 dr). The tetracyclic 1,7-fused indoles were efficiently obtained from readily available starting materials under mild conditions. This methodology displays impressive substrate generality with two reaction components. The products resulting from this doubly annulative strategy are useful synthetic intermediates.

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