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1.
Adv Sci (Weinh) ; : e2405907, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324579

RESUMEN

LACTB is identified as a tumor suppressor in several tumors. However, preliminary study reveals that LACTB is overexpressed in osteosarcoma and indicates poor prognosis. Two missense mutations (rs34317102 and rs2729835) exist simultaneously in 92.31% of osteosarcoma patients and cause M5L and R469K double mutations in LACTB, suggesting the biologic function of LACTB protein may be altered in osteosarcoma. Moreover, LACTBM5L+R469K overexpression can promote malignant progression in different tumors, which suggests that the M5L and R469K mutations confer oncogene-like functions to LACTB. Mechanistically, LACTBM5L+R469K not only reduces the wild type p53 via enhancing PSMB7 catalytic activity, but also protects p53R156P protein from lysosomal degradation, which suggesting LACTBM5L+R469K is a dual-regulator for wt-p53 and mutant p53, and derive oncogene-like functions. More importantly, clavulanate potassium, a bacterial ß-lactamase inhibitor, can inhibit osteosarcoma proliferation and sensitize osteosarcoma to cisplatin by binding and blocking LACTBM5L+R469K. These findings revealed that the M5L and R469K double mutations can diminish the tumor suppressive ability of wild type LACTB and provide oncogene-like functions to LACTB. Inhibiting LACTBM5L+R469K can suppress the progression of osteosarcoma harbouring wild-type or mutant p53. Clavulanate potassium is a promising drug by targeting LACTBM5L+R469K-p53 pathway for the treatment of osteosarcoma patients.

2.
J Mater Chem B ; 12(36): 8812-8824, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39150370

RESUMEN

In situ monitoring of biological processes between different organelles upon oxidative stress is one of the most important research hotspots. Fluorescence imaging is especially suitable for biomedical applications due to its distinct advantages of high spatiotemporal resolution, high sensitivity, non-invasiveness, and in situ monitoring capabilities. However, most fluorescent probes can only achieve light-up imaging of single organelles, thus the combined use of two or more probes is usually required for monitoring biological processes between organelles, which can suffer from tedious staining and washing procedures, increased cytotoxicity and poor photostability. Exogenetic oxidants can affect broad-spectrum subcellular organelles, which are not conducive to in situ monitoring of biological processes between specific organelles. To tackle these challenges, a series of dual-/multi-organelle-targeted aggregation-induced emission (AIE) probes associated with oxidative stress have been designed and developed in the past few years. Herein, the recent progress of these AIE probes is summarized in biomedical applications, such as apoptosis monitoring, interplay between organelles, microenvironmental changes of organelles, organelle morphology tracking, precise cancer therapy, and so forth. Moreover, the further outlook for dual-/multi-organelle-targeted AIE probes is discussed, aiming to promote innovative research in biomedical applications.


Asunto(s)
Colorantes Fluorescentes , Imagen Óptica , Orgánulos , Estrés Oxidativo , Estrés Oxidativo/efectos de los fármacos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Humanos , Orgánulos/metabolismo , Orgánulos/química , Orgánulos/efectos de los fármacos , Animales
3.
Angew Chem Int Ed Engl ; : e202412922, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175166

RESUMEN

Chalcogens are used as sensitive redox-responsive reagents in tumor therapy. However, chalcogen bonds triggered by external ionizing radiation, rather than by internal environmental stimuli, enable site-directed and real-time drug degradation in target lesions. This approach helps to bypass chemoresistance and global systemic toxicity, presenting a significant advancement over traditional chemoradiotherapy. In this study, we fabricated a hybrid monodisperse organosilica nanoprodrug based on homonuclear single bonds (disulfide bonds (S-S, approximately 240 kJ/mol), diselenium bonds (Se-Se, approximately 172 kJ/mol), and tellurium bonds (Te-Te, 126 kJ/mol)), including ditelluride-bond-bridged MONs (DTeMSNs), diselenide-bond-bridged MONs (DSeMSNs) and disulfide-bond-bridged MONs (DSMSNs). The results demonstrated that differences in electronegativities and atomic radii influenced their oxidation sensitivities and reactivities. Tellurium, with the lowest electronegativity, showed the highest sensitivity, followed by selenium and sulfur. DTeMSNs exhibited highly responsive cleavage upon exposure to X-rays, resulting in oxidation to TeO32-. Furthermore, chalcogen-hybridized organosilica was loaded with manganese ions (Mn2+) to enhance the release of Mn2+ during radiotherapy, thereby activating the the stimulator of interferon genes (STING) pathway and enhancing the tumor immune response to inhibit tumor growth. This investigation of hybrid organosilica deepens our understanding of chalcogens response characteristics to radiotherapy and enriches the design principles for nanomedicine based on prodrugs.

4.
Nat Immunol ; 25(8): 1367-1382, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38992254

RESUMEN

Upregulation of diverse self-antigens that constitute components of the inflammatory response overlaps spatially and temporally with the emergence of pathogen-derived foreign antigens. Therefore, discrimination between these inflammation-associated self-antigens and pathogen-derived molecules represents a unique challenge for the adaptive immune system. Here, we demonstrate that CD8+ T cell tolerance to T cell-derived inflammation-associated self-antigens is efficiently induced in the thymus and supported by redundancy in cell types expressing these molecules. In addition to thymic epithelial cells, this included thymic eosinophils and innate-like T cells, a population that expressed molecules characteristic for all major activated T cell subsets. We show that direct T cell-to-T cell antigen presentation by minute numbers of innate-like T cells was sufficient to eliminate autoreactive CD8+ thymocytes. Tolerance to such effector molecules was of critical importance, as its breach caused by decreased thymic abundance of a single model inflammation-associated self-antigen resulted in autoimmune elimination of an entire class of effector T cells.


Asunto(s)
Presentación de Antígeno , Autoantígenos , Linfocitos T CD8-positivos , Inflamación , Timocitos , Timo , Animales , Autoantígenos/inmunología , Linfocitos T CD8-positivos/inmunología , Ratones , Timo/inmunología , Inflamación/inmunología , Presentación de Antígeno/inmunología , Timocitos/inmunología , Timocitos/metabolismo , Ratones Endogámicos C57BL , Inmunidad Innata , Autoinmunidad/inmunología , Tolerancia Inmunológica/inmunología , Ratones Transgénicos , Ratones Noqueados , Activación de Linfocitos/inmunología , Eosinófilos/inmunología
5.
Acta Biomater ; 183: 292-305, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38838903

RESUMEN

Limited success has been achieved in ferroptosis-induced cancer treatment due to the challenges related to low production of toxic reactive oxygen species (ROS) and inherent ROS resistance in cancer cells. To address this issue, a self-assembled nanodrug have been investigated that enhances ferroptosis therapy by increasing ROS production and reducing ROS inhibition. The nanodrug is constructed by allowing doxorubicin (DOX) to interact with Fe2+ through coordination interactions, forming a stable DOX-Fe2+ chelate, and this chelate further interacts with sorafenib (SRF), resulting in a stable and uniform nanoparticle. In tumor cells, overexpressed glutathione (GSH) triggers the disassembly of nanodrug, thereby activating the drug release. Interestingly, the released DOX not only activates nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) to produce abundant H2O2 production for enhanced ROS production, but also acts as a chemotherapeutics agent, synergizing with ferroptosis. To enhance tumor selectivity and improve the blood clearance, the nanodrug is coated with a related cancer cell membrane, which enhances the selective inhibition of tumor growth and metastasis in a B16F10 mice model. Our findings provide valuable insights into the rational design of self-assembled nanodrug for enhanced ferroptosis therapy in cancer treatment. STATEMENT OF SIGNIFICANCE: Ferroptosis is a non-apoptotic form of cell death induced by the iron-regulated lipid peroxides (LPOs), offering a promising potential for effective and safe anti-cancer treatment. However, two significant challenges hinder its clinical application: 1) The easily oxidized nature of Fe2+ and the low concentration of H2O2 leads to a low efficiency of intracellular Fenton reaction, resulting in poor therapeutic efficacy; 2) The instinctive ROS resistance of cancer cells induce drug resistance. Therefore, we developed a simple and high-efficiency nanodrug composed of self-assembling by Fe2+ sources, H2O2 inducer and ROS resistance inhibitors. This nanodrug can effectively deliver the Fe2+ sources into tumor tissue, enhance intracellular concentration of H2O2, and reduce ROS resistance, achieving a high-efficiency, precise and safe ferroptosis therapy.


Asunto(s)
Antineoplásicos , Doxorrubicina , Ferroptosis , Nanopartículas , Especies Reactivas de Oxígeno , Animales , Ferroptosis/efectos de los fármacos , Doxorrubicina/farmacología , Doxorrubicina/química , Nanopartículas/química , Humanos , Especies Reactivas de Oxígeno/metabolismo , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Línea Celular Tumoral , Ratones Endogámicos C57BL , Membrana Celular/metabolismo , Membrana Celular/efectos de los fármacos , Sinergismo Farmacológico
6.
Biomaterials ; 311: 122650, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38889598

RESUMEN

The dysfunction of bone mesenchymal stem cells (BMSCs), caused by the physical and chemical properties of the inflammatory and repair phases of bone regeneration, contributes to the failure of bone regeneration. To meet the spatiotemporal needs of BMSCs in different phases, designing biocompatible materials that respond to external stimuli, improve migration in the inflammatory phase, reduce apoptosis in the proliferative phase, and clear the hurdle in the differentiation phase of BMSCs is an effective strategy for multistage repair of bone defects. In this study, we designed a cascade-response functional composite hydrogel (Gel@Eb/HA) to regulate BMSCs dysfunction in vitro and in vivo. Gel@Eb/HA improved the migration of BMSCs by upregulating the expression of chemokine (C-C motif) ligand 5 (CCL5) during the inflammatory phase. Ultrasound (US) triggered the rapid release of Ebselen (Eb), eliminating the accumulation of reactive oxygen species (ROS) in BMSCs, and reversing apoptosis under oxidative stress. Continued US treatment accelerated the degradation of the materials, thereby providing Ca2+ for the osteogenic differentiation of BMSCs. Altogether, our study highlights the prospects of US-controlled intelligent system, that provides a novel strategy for addressing the complexities of multistage bone repair.


Asunto(s)
Regeneración Ósea , Hidrogeles , Células Madre Mesenquimatosas , Osteogénesis , Regeneración Ósea/efectos de los fármacos , Animales , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Hidrogeles/química , Osteogénesis/efectos de los fármacos , Ondas Ultrasónicas , Diferenciación Celular/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ratas Sprague-Dawley , Apoptosis/efectos de los fármacos , Masculino , Ratones , Quimiocina CCL5/metabolismo , Movimiento Celular/efectos de los fármacos
7.
Anal Chem ; 96(6): 2534-2542, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38302490

RESUMEN

Cerebrospinal fluid (CSF) biomarkers are more sensitive than the Movement Disorder Society (MDS) criteria for detecting prodromal Parkinson's disease (PD). Early detection of PD provides the best chance for successful implementation of disease-modifying treatments, making it crucial to effectively identify CSF extracted from PD patients or normal individuals. In this study, an intelligent sensor array was built by using three metal-organic frameworks (MOFs) that exhibited varying catalytic kinetics after reacting with potential protein markers. Machine learning algorithms were used to process fingerprint response patterns, allowing for qualitative and quantitative assessment of the proteins. The results were robust and capable of discriminating between PD and non-PD patients via CSF detection. The k-nearest neighbor regression algorithm was used to predict MDS scores with a minimum mean square error of 38.88. The intelligent MOF sensor array is expected to promote the detection of CSF biomarkers due to its ability to identify multiple targets and could be used in conjunction with MDS criteria and other techniques to diagnose PD more sensitively and selectively.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico , Biomarcadores/líquido cefalorraquídeo , Diagnóstico Precoz , Algoritmos , Aprendizaje Automático
8.
Luminescence ; 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38073054

RESUMEN

The development of photoactivatable aggregation-induced emission (AIE) probes is one of the hotspots for bioimaging and imaging-guided precise disease therapy due to the distinct advantages of high spatiotemporal resolution, precise spatiotemporal controllability, and noninvasiveness of light. To design and develop novel photoactivatable AIE probes, functional groups based on photodehydrogenation reaction mechanisms are combined with the AIE-active skeleton. Here, the recent progress in biomedical applications of photoactivatable AIE probes based on photocyclodehydrogenation and photo-oxidative dehydrogenation reactions are summarized briefly. Moreover, the outlook for photoactivatable AIE probes is discussed to aim at promoting innovative research in biomedical applications.

9.
ACS Sens ; 8(12): 4587-4596, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38038440

RESUMEN

Ascorbic acid (AA) is significant in protecting the brain from further damage and maintaining brain homeostasis after ischemia stroke (IS); however, the dynamic change of cerebral AA content after different degrees of ischemic stroke is still unclear. Herein, carboxylated single-walled carbon nanotube (CNT-COOH)- and polyethylenedioxythiophene (PEDOT)-modified carbon fiber microelectrodes (CFEs) were proposed to detect in situ cerebral AA with sensitivity, selectivity, and stability. Under differential pulse voltammetry scanning, the CFE/CNT-COOH/PEDOT gave a ratiometric, electrochemically responsive signal. The internal standard peak at -310 mV was from the reversible peak of O2 reduction and the deprotonation and protonation of quinone groups, while AA was oxidized at -70 mV. In vivo experimental results indicated that the cerebral AA level gradually increased with the ischemic time increasing in different middle cerebral artery occlusion (MCAO) model mice. This work implies that the increasing cerebral AA level may be highly related to the glutamate excitotoxicity and ROS-led cell apoptosis and paves a new way for further understanding the release and metabolic mechanisms of AA during ischemia reperfusion and IS.


Asunto(s)
Ácido Ascórbico , Encéfalo , Ratas , Ratones , Animales , Ácido Ascórbico/química , Ratas Sprague-Dawley , Encéfalo/metabolismo , Reperfusión , Isquemia/metabolismo
10.
Nano Lett ; 23(18): 8628-8636, 2023 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-37694968

RESUMEN

Magnetic resonance imaging (MRI) is an important tool in the diagnosis of many cancers. However, clinical gadolinium (Gd)-based MRI contrast agents have limitations, such as large doses and potential side effects. To address these issues, we developed a hydrogen-bonded organic framework-based MRI contrast agent (PFC-73-Mn). Due to the hydrogen-bonded interaction of water molecules and the restricted rotation of manganese ions, PFC-73-Mn exhibits high longitudinal relaxation r1 (5.03 mM-1 s-1) under a 3.0 T clinical MRI scanner. A smaller intravenous dose (8 µmol of Mn/kg) of PFC-73-Mn can provide strong contrast and accurate diagnosis in multiple kinds of cancers, including breast tumor and ultrasmall orthotopic glioma. PFC-73-Mn represents a prospective new approach in tumor imaging, especially in early-stage cancer.


Asunto(s)
Glioma , Manganeso , Humanos , Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética/métodos
11.
ACS Appl Mater Interfaces ; 15(28): 33239-33249, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37399544

RESUMEN

Rheumatoid arthritis (RA) is an autoimmune and inflammatory disease that is so far incurable with long-term health risks. The high doses and frequent administration for the available RA drug always lead to adverse side effects. Aiming at the obstacles to achieving effective RA treatment, we prepared macrophage cell membrane-camouflaged nanoparticles (M-EC), which were assembled from epigallocatechin gallate (EGCG) and cerium(IV) ions. Due to its geometrical similarity to the active metal sites of a natural antioxidant enzyme, the EC possessed a high scavenge efficiency to various types of reactive oxygen species (ROS) and reactive nitrogen species (RNS). The macrophage cell membrane assisted M-EC in escaping from the immune system, being uptaken by inflammatory cells, and specifically binding IL-1ß. After tail vein injection to the collagen-induced arthritis (CIA) mouse model, the M-EC accumulated at inflamed joints and effectively repaired the bone erosion and cartilage damage of rheumatoid arthritis by relieving synovial inflammation and cartilage erosion. It is expected that the M-EC can not only pave a new way for designing metal-phenolic networks with better biological activity but also provide a more biocompatible therapeutic strategy for effective treatment of RA.


Asunto(s)
Artritis Reumatoide , Cerio , Ratones , Animales , Cerio/farmacología , Cerio/uso terapéutico , Biomimética , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Inflamación/tratamiento farmacológico
12.
Chem Commun (Camb) ; 59(61): 9352-9355, 2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37431730

RESUMEN

Transarterial chemoembolization (TACE) is one of the most commonly used treatments for hepatocellular carcinoma (HCC); however, the poor stability of emulsified chemotherapy drugs by iodinated oil always leads to serious systemic cytotoxicity. Herein, a composite hydrogel Epi/Etpoil@MC/XG was proposed by stably distributing ethiodized poppyseed oil (Etpoil) and epirubicin (Epi) in the blend hydrogel of methylcellulose (MC) and xanthan gum (XG). Benefiting from its adjusted thermo-responsive and injectable properties, the Epi/Etpoil@MC/XG has been successfully applied in the embolization of the feeding artery for a VX2 tumor model.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Hidrogeles/uso terapéutico , Epirrubicina/farmacología , Epirrubicina/uso terapéutico , Aceite Etiodizado/uso terapéutico , Arterias
13.
Anal Chem ; 95(21): 8267-8276, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37191204

RESUMEN

Patients with triple-negative breast cancer (TNBC) have dismal prognoses due to the lack of therapeutic targets and susceptibility to lymph node (LN) metastasis. Therefore, it is essential to develop more effective approaches to identify early TNBC tissues and LNs. In this work, a magnetic resonance imaging (MRI) contrast agent (Mn-iCOF) was constructed based on the Mn(II)-chelated ionic covalent organic framework (iCOF). Because of the porous structure and hydrophilicity, the Mn-iCOF has a high longitudinal relaxivity (r1) of 8.02 mM-1 s-1 at 3.0 T. For the tumor-bearing mice, a lower dose (0.02 mmol [Mn]/kg) of Mn-iCOF demonstrated a higher signal-to-noise ratio (SNR) value (1.8) and longer retention time (2 h) compared to a 10-fold dose of commercial Gd-DOTA (0.2 mmol [Gd]/kg). Moreover, the Mn-iCOF can provide continuous and significant MR contrast for the popliteal LNs within 24 h, allowing for accurate evaluation and dissection of LNs. These excellent MRI properties of the Mn-iCOF may open new avenues for designing more biocompatible MRI contrast agents with higher resolutions, particularly in the diagnosis of TNBC.


Asunto(s)
Estructuras Metalorgánicas , Neoplasias de la Mama Triple Negativas , Humanos , Ratones , Animales , Estructuras Metalorgánicas/química , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Medios de Contraste/química , Espectroscopía de Resonancia Magnética
14.
Vaccine ; 40(32): 4371-4379, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35750539

RESUMEN

AIM: To evaluate the safety and immunogenicity of rabies vaccine for human use after post-exposure in China. METHODS: A systematic search was performed from PubMed, EMBASE, CNKI and Cochrane Library database, supplemented by manual retrieval. According to the inclusion and exclusion criteria, a meta-analysis was performed using Stata 16.0 software after independent literature screening, data extraction and quality assessment by two evaluators. RESULTS: A total of 32 studies were included. It was found that rabies vaccination after PEP could induce the body to produce sufficient RVNA. Both Essen and Zagreb regimens showed good immunogenicity, with no significant difference in systemic events and local events after PEP, but a relatively high incidence of local and systemic events after PEP under the Zagreb regimen. CONCLUSION: For the Chinese population, rabies vaccination after PEP has shown relatively a good immune efficacy and acceptable safety for preventing human rabies. The survey also found that the Zagreb regimen was comparable to the Essen regimen in terms of rabies prophylaxis with an acceptable safety profile.


Asunto(s)
Profilaxis Posexposición , Vacunas Antirrábicas , Rabia , Anticuerpos Antivirales , China , Humanos , Inmunogenicidad Vacunal , Rabia/prevención & control , Vacunas Antirrábicas/efectos adversos , Vacunas Antirrábicas/uso terapéutico
15.
J Nanobiotechnology ; 20(1): 104, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35246149

RESUMEN

BACKGROUND: Hypoxia is an important factor that contributes to chemoresistance and metastasis in triple negative breast cancer (TNBC), and alleviating hypoxia microenvironment can enhance the anti-tumor efficacy and also inhibit tumor invasion. METHODS: A near-infrared (NIR) responsive on-demand oxygen releasing nanoplatform (O2-PPSiI) was successfully synthesized by a two-stage self-assembly process to overcome the hypoxia-induced tumor chemoresistance and metastasis. We embedded drug-loaded poly (lactic-co-glycolic acid) cores into an ultrathin silica shell attached with paramagnetic Gd-DTPA to develop a Magnetic Resonance Imaging (MRI)-guided NIR-responsive on-demand drug releasing nanosystem, where indocyanine green was used as a photothermal converter to trigger the oxygen and drug release under NIR irradiation. RESULTS: The near-infrared responsive on-demand oxygen releasing nanoplatform O2-PPSiI was chemically synthesized in this study by a two-stage self-assembly process, which could deliver oxygen and release it under NIR irradiation to relieve hypoxia, improving the therapeutic effect of chemotherapy and suppressed tumor metastasis. This smart design achieves the following advantages: (i) the O2 in this nanosystem can be precisely released by an NIR-responsive silica shell rupture; (ii) the dynamic biodistribution process of O2-PPSiI was monitored in real-time and quantitatively analyzed via sensitive MR imaging of the tumor; (iii) O2-PPSiI could alleviate tumor hypoxia by releasing O2 within the tumor upon NIR laser excitation; (iv) The migration and invasion abilities of the TNBC tumor were weakened by inhibiting the process of EMT as a result of the synergistic therapy of NIR-triggered O2-PPSiI. CONCLUSIONS: Our work proposes a smart tactic guided by MRI and presents a valid approach for the reasonable design of NIR-responsive on-demand drug-releasing nanomedicine systems for precise theranostics in TNBC.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Neoplasias de la Mama Triple Negativas , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos , Hipoxia/diagnóstico por imagen , Hipoxia/tratamiento farmacológico , Imagen por Resonancia Magnética , Nanopartículas/uso terapéutico , Oxígeno/farmacología , Medicina de Precisión , Distribución Tisular , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Microambiente Tumoral
17.
Front Bioeng Biotechnol ; 9: 758482, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34708029

RESUMEN

Owing to high blood sugar level and chronic inflammation, diabetes tend to cause the overproduction of free radicals in body, which will damage tissue and cells, reduce autoimmunity, and greatly increase the incidence of tumors. Selenium nanoparticles (SeNPs) exhibit high antioxidant activity with anti-tumor ability. In addition, metformin is considered as a clinical drug commonly for the treatment of stage II diabetes. Therefore, in this study, different functionalized SeNPs combined with metformin were performed to detect the feasibility for cancer therapy. The combination of Tween 80 (TW80)-SeNPs and metformin was found to have a synergistic effect on MCF-7 cells. The mechanism of this synergistic effect involved in the induction of DNA damage by affecting the generation of reactive oxygen species through selenoproteins; the upregulation of DNA-damage-related proteins including p-ATM, p-ATR, and p38; the promotion of p21 expression; and the downregulation of cyclin-dependent kinases and cyclin-related proteins causing cell cycle arrest. Furthermore, the expression of AMPK was affected, which in turn to regulate the mitochondrial membrane potential to achieve the synergistic treatment effect.

18.
Immunity ; 54(9): 2005-2023.e10, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34525339

RESUMEN

Cell fate decisions during early B cell activation determine the outcome of responses to pathogens and vaccines. We examined the early B cell response to T-dependent antigen in mice by single-cell RNA sequencing. Early after immunization, a homogeneous population of activated precursors (APs) gave rise to a transient wave of plasmablasts (PBs), followed a day later by the emergence of germinal center B cells (GCBCs). Most APs rapidly exited the cell cycle, giving rise to non-GC-derived early memory B cells (eMBCs) that retained an AP-like transcriptional profile. Rapid decline of antigen availability controlled these events; provision of excess antigen precluded cell cycle exit and induced a new wave of PBs. Fate mapping revealed a prominent contribution of eMBCs to the MBC pool. Quiescent cells with an MBC phenotype dominated the early response to immunization in primates. A reservoir of APs/eMBCs may enable rapid readjustment of the immune response when failure to contain a threat is manifested by increased antigen availability.


Asunto(s)
Linfocitos B/inmunología , Centro Germinal/inmunología , Inmunidad Humoral/inmunología , Memoria Inmunológica/inmunología , Activación de Linfocitos/inmunología , Animales , Presentación de Antígeno/inmunología , Diferenciación Celular/inmunología , Ratones , Células Plasmáticas/inmunología , Células Precursoras de Linfocitos B/inmunología
19.
ACS Appl Mater Interfaces ; 13(30): 35376-35388, 2021 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-34313109

RESUMEN

Escorting therapeutics for malignancies by nano-encapsulation to ameliorate treatment effects and mitigate side effects has been pursued in precision medicine. However, the majority of drug delivery systems suffer from uncontrollable drug release kinetics and thus lead to unsatisfactory triggered-release efficiency along with severe side effects. Herein, we developed a unique nanovesicle delivery system that shows near-infrared (NIR) light-triggered drug release behavior and minimal premature drug release. By co-encapsulation of superparamagnetic iron oxide (SPIO) nanoparticles, the ultrasound contrast agent perfluorohexane (PFH), and cisplatin in a silicate-polyaniline vesicle, we achieved the controllable release of cisplatin in a thermal-responsive manner. Specifically, vaporization of PFH triggered by the heat generated from NIR irradiation imparts high inner vesicle pressure on the nanovesicles, leading to pressure-induced nanovesicle collapse and subsequent cisplatin release. Moreover, the multimodal imaging capability can track tumor engagement of the nanovesicles and assess their therapeutic effects. Due to its precise inherent NIR-triggered drug release, our system shows excellent tumor eradication efficacy and biocompatibility in vivo, empowering it with great prospects for future clinical translation.


Asunto(s)
Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Medios de Contraste/química , Portadores de Fármacos/química , Fluorocarburos/química , Neoplasias/tratamiento farmacológico , Células A549 , Compuestos de Anilina/química , Compuestos de Anilina/efectos de la radiación , Compuestos de Anilina/toxicidad , Animales , Antineoplásicos/química , Antineoplásicos/toxicidad , Cisplatino/química , Cisplatino/toxicidad , Medios de Contraste/toxicidad , Portadores de Fármacos/efectos de la radiación , Portadores de Fármacos/toxicidad , Liberación de Fármacos , Quimioterapia , Fluorocarburos/toxicidad , Humanos , Rayos Infrarrojos , Nanopartículas Magnéticas de Óxido de Hierro/química , Nanopartículas Magnéticas de Óxido de Hierro/efectos de la radiación , Nanopartículas Magnéticas de Óxido de Hierro/toxicidad , Ratones Desnudos , Terapia Fototérmica , Silicatos/química , Silicatos/toxicidad , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Sci Total Environ ; 794: 148662, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34225158

RESUMEN

Differentiating and clarifying the driving factors behind streamflow changes are critical for highlighting hydrological responses to changing environments. However, due to the limited number of hydrological stations, the dominant factor controlling global observed streamflow change remains unclear and intensely debated. Here, we revisit this scientific issue by using the most comprehensive dataset to attribute the observed global streamflow changes during 1960-2014. The results suggest that other factors than precipitation (P) and potential evaporation (E0) are the most important contributors to global observed streamflow changes, which dominate streamflow change for 48.9-50.9% of the stations. In contrast, the dominant factor translated into P in 72.3-72.9% of stations when using reconstructed streamflow datasets, in agreement with most previous global assessments. These differences indicate that streamflow attributions using reconstructed streamflow might overestimate the effects of P while underestimating the roles of other factors, such as the vegetation and human impact. At the global scale, the other factors affected by many catchment characteristics and their impacts on streamflow change have remarkable regional differences. This study highlights the necessity to apply the observed data in streamflow attribution to avoid biased conclusions regarding the dominant factor of streamflow changes.


Asunto(s)
Cambio Climático , Ríos , Humanos , Hidrología
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