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1.
Appl Opt ; 61(29): 8649-8656, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36255997

RESUMEN

A shotcreting robot needs to reconstruct the arch surface in three dimensions (3D) during the process of spraying a tunnel. To solve this problem, we propose an improved marching cube (MC) reconstruction method based on a point cloud splice and normal re-orient. First, we use the explosion-proof LIDAR to acquire the point cloud data of the tunnel arch, followed by the use of the iterative closest point algorithm, a PassThrough filter, and a StatisticalOutlierRemoval filter for point cloud splicing, data segmentation, and simplification, respectively. In order to improve the reconstruction accuracy, we adjusted the estimated point cloud normal for normal consistency and obtained the geometric features of the complex point cloud surface. Furthermore, combined with the improved MC algorithm, the 3D reconstruction of the tunnel arch is realized. The experimental results show that the proposed method can reconstruct the 3D model of the tunnel arch surface quickly and accurately, which lays a foundation for further research on a trajectory plan, spraying status monitors, and control strategies.

2.
Sensors (Basel) ; 22(16)2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-36015963

RESUMEN

In obstacle spatial path planning, the traditional A* algorithm has the problem of too many turning points and slow search speed. With this in mind, a path planning method that improves the A* (A-Star) algorithm is proposed. The mobile robot platform was equipped with a lidar and inertial measurement unit (IMU). The Hdl_graph_slam mapping algorithm was used to construct a two-dimensional grid map, and the improved A* algorithm was used for path planning of the mobile robot. The algorithm introduced the path smoothing strategy and safety protection mechanism, and it eliminated redundant points and minimal corner points by judging whether there were obstacles in the connection of two path nodes. The algorithm effectively improved the smoothness of the path and facilitated the robot to move in the actual operation. It could avoid the wear of the robot by expanding obstacles and improving the safety performance of the robot. Subsequently, the algorithm introduced the steering cost model and the adaptive cost function to improve the search efficiency, making the search purposeful and effective. Lastly, the effectiveness of the proposed algorithm was verified by experiments. The average path search time was reduced by 13%. The average search extension node was reduced by 11%. The problems of too many turning points and slow search speed of traditional A* algorithm in path planning were improved.

3.
Nano Lett ; 20(3): 1928-1933, 2020 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-32073871

RESUMEN

Immunogenic cell death (ICD) elicited by photodynamic therapy (PDT) is mediated through generation of reactive oxygen species (ROS) that induce endoplasmic reticulum (ER) stress. However, the half-life of ROS is very short and the intracellular diffusion depth is limited, which impairs ER localization and thus limits ER stress induction. To solve the problem, we synthesized reduction-sensitive Ds-sP NPs (PEG-s-s-1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] nanoparticles) loaded with an efficient ER-targeting photosensitizer TCPP-TER (4,4',4″,4'″-(porphyrin-5,10,15,20-tetrayl)tetrakis(N-(2-((4-methylphenyl)sulfonamido)ethyl)benzamide). The resulting Ds-sP/TCPP-TER NPs could selectively accumulate in the ER and locally generate ROS under near-infrared (NIR) laser irradiation, which induced ER stress, amplified ICD, and activated immune cells, leading to augmented immunotherapy effect. This study presents a novel ICD amplifying, ER-targeting PDT strategy that can effectively eradicate primary tumors under NIR exposure, as well as distant tumors through an abscopal effect.


Asunto(s)
Sistemas de Liberación de Medicamentos , Estrés del Retículo Endoplásmico , Retículo Endoplásmico , Inmunoterapia , Rayos Infrarrojos , Neoplasias Experimentales , Animales , Muerte Celular/efectos de los fármacos , Muerte Celular/inmunología , Línea Celular Tumoral , Retículo Endoplásmico/inmunología , Retículo Endoplásmico/patología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Estrés del Retículo Endoplásmico/inmunología , Estrés del Retículo Endoplásmico/efectos de la radiación , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/inmunología , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Especies Reactivas de Oxígeno/inmunología
4.
J Am Chem Soc ; 142(36): 15320-15330, 2020 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-32820914

RESUMEN

Current chemodynamic therapy (CDT) primarily relies on the delivery of transition metal ions with Fenton activity to trigger hydroxyl radical production from hydrogen peroxide. However, administration of an excess amount of exogenous Fenton-type heavy metals may cause potential adverse effects to human health, including acute and chronic damages. Here, we present a new CDT strategy that uses intracellular labile iron pool (LIP) as the endogenous source of Fenton-reactive metals for eliciting free radical generation, and the discovery of hydroperoxides (R'OOH) as an optimal LIP-mediated chemodynamic agent against cancer. By simulating the metabolic fates of peroxo compounds within cells, R'OOH was found to have excellent free radical-producing ability in the presence of labile iron(II) and to suffer only moderate elimination by glutathione/glutathione peroxidase, which contributes to its superior chemodynamic efficacy. The LIP-initiated nontoxic-to-toxic transition of R'OOH, together with increased LIP levels in tumor cells, enabled efficient and specific CDT of cancer. Moreover, pH/labile iron(II) cascade-responsive nanomedicines comprising encapsulated methyl linoleate hydroperoxide and LIP-increasing agent in pH-sensitive polymer particles were fabricated to realize enhanced CDT. This work not only paves the way to using endogenous Fenton-type metals for cancer therapy but also offers a paradigm for the exploration of high-performance chemodynamic agents activated by intracellular LIP.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Encefálicas/terapia , Compuestos Ferrosos/metabolismo , Radicales Libres/metabolismo , Glioblastoma/terapia , Peróxidos/farmacología , Terapia Fototérmica , Antineoplásicos/química , Antineoplásicos/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Compuestos Ferrosos/química , Radicales Libres/química , Glioblastoma/patología , Humanos , Imagen Óptica , Peróxidos/química , Peróxidos/metabolismo
5.
J Am Chem Soc ; 142(14): 6822-6832, 2020 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-32196319

RESUMEN

Biocatalytic reactions in living cells involve complex transformations in the spatially confined microenvironments. Inspired by biological transformation processes, we demonstrate effective biocatalytic cascade driven photodynamic therapy in tumor-bearing mice by the integration of an artificial enzyme (ultrasmall Au nanoparticles) with upconversion nanoparticles (NaYF4@NaYb0.92F4:Er0.08@NaYF4)zirconium/iron porphyrin metal-organic framework core-shell nanoparticles (UMOF NPs) which act as biocatalysts and nanoreactors. The construction of core-shell UMOF NPs are realized by using a unique "solvent-assisted self-assembly" method. The integration of ultrasmall AuNPs on the UMOFs matrix leads to glucose depletion, providing Au-mediated cancer therapy via glucose oxidase like catalytic activity. Meanwhile, the UMOF matrix acts as a near-infrared (NIR) light photon-activated singlet oxygen generator through a continuous supply of oxygen via hydrogen peroxide decomposition upon irradiation. Such kinds of biocatalysts offer exciting opportunities for biomedical, catalytical ,and energy applications.


Asunto(s)
Nanopartículas del Metal/química , Estructuras Metalorgánicas/metabolismo , Fotoquimioterapia/métodos , Humanos
6.
Small ; 15(41): e1903422, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31448577

RESUMEN

Gd chelates have occupied most of the market of magnetic resonance imaging (MRI) contrast agents for decades. However, there have been some problems (nephrotoxicity, non-specificity, and low r1 ) that limit their applications. Herein, a wet-chemical method is proposed for facile synthesis of poly(acrylic acid) (PAA) stabilized exceedingly small gadolinium oxide nanoparticles (ES-GON-PAA) with an excellent water dispersibility and a size smaller than 2.0 nm, which is a powerful T1 -weighted MRI contrast agent for diagnosis of diseases due to its remarkable relaxivities (r1 = 70.2 ± 1.8 mM-1 s-1 , and r2 /r1 = 1.02 ± 0.03, at 1.5 T). The r1 is much higher and the r2 /r1 is lower than that of the commercial Gd chelates and reported gadolinium oxide nanoparticles (GONs). Further ES-GON-PAA is developed with conjugation of RGD2 (RGD dimer) (i.e., ES-GON-PAA@RGD2) for T1 -weighted MRI of tumors that overexpress RGD receptors (i.e., integrin αv ß3 ). The maximum signal enhancement (ΔSNR) for T1 -weighted MRI of tumors reaches up to 372 ± 56% at 2 h post-injection of ES-GON-PAA@RGD2, which is much higher than commercial Gd-chelates (<80%). Due to the high biocompatibility and high tumor accumulation, ES-GON-PAA@RGD2 with remarkable relaxivities is a promising and powerful T1 -weighted MRI contrast agent.


Asunto(s)
Gadolinio/química , Imagen por Resonancia Magnética , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Tamaño de la Partícula , Resinas Acrílicas/química , Línea Celular Tumoral , Humanos , Nanopartículas/ultraestructura
7.
Bioconjug Chem ; 30(6): 1745-1753, 2019 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-31181890

RESUMEN

As highly expressed in insulinomas, the glucagon-like peptide-1 receptor (GLP-1R) is believed to be an attractive target for diagnosis, localization, and treatment with radiolabeled exendin 4. However, the high and persistent radioactivity accumulation of exendin 4 in the kidneys limits accurate diagnosis and safe, as well as effective, radiotherapy in insulinomas. In this study, we intend to reduce the renal accumulation of radiolabeled exendin 4 through degradation mediated by brush border membrane enzymes. A new exendin 4 ligand NOTA-MVK-Cys40-Leu14-Exendin 4 containing Met-Val-Lys (MVK) linker between the peptide and 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) chelator was synthesized and labeled with 68Ga. The in vitro mouse serum stability and cell binding affinity of the tracer were evaluated. Initial in vitro cleavage of the linker was determined by incubation of a model compound Boc-MVK-Dde with brush border membrane vesicles (BBMVs) with and without the inhibitor of neutral endopeptidase (NEP). Further cleavage studies were performed with the full structure of NOTA-MVK-Cys40-Leu14-Exendin 4. Kidney and urine samples were collected in the in vivo metabolism study after intravenous injection of 68Ga-NOTA-MVK-Cys40-Leu14-Exendin 4. The microPET images were acquired in INS-1 tumor model at different time points; the radioactivity uptake of 68Ga-NOTA-MVK-Cys40-Leu14-Exendin 4 in tumor and kidneys were determined and compared with the control radiotracer without MVK linker. 68Ga-NOTA-MVK-Cys40-Leu14-Exendin 4 was stable in mouse serum. The MVK modification did not affect the affinity of NOTA-MVK-Cys40-Leu14-Exendin 4 toward GLP-1R. The in vitro cleavage study and in vivo metabolism study confirmed that the MVK sequence can be recognized by BBM enzymes and cleaved at the amide bond between Met and Val, thus releasing the small fragment containing Met. MicroPET images showed that the tumor uptake of 68Ga-NOTA-MVK-Cys40-Leu14-Exendin 4 was comparable to that of the control, while the kidney uptake was significantly reduced. As a result, more favorable tumor to kidney ratios were achieved. In this study, a novel exendin 4 analogue, NOTA-MVK-Cys40-Leu14-Exendin 4, was successfully synthesized and labeled with 68Ga. With the cleavable MVK sequence, this ligand could be cleaved by the enzymes on kidneys, and releasing the fragment of 68Ga-NOTA-Met-OH, which will rapidly excrete from urine. As the high and consistent renal radioactivity accumulation could be significantly reduced, NOTA-MVK-Cys40-Leu14-Exendin 4 shows great potential in the diagnosis and radiotherapy for insulinoma.


Asunto(s)
Exenatida/farmacocinética , Radioisótopos de Galio/farmacocinética , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Insulinoma/diagnóstico por imagen , Animales , Exenatida/química , Exenatida/uso terapéutico , Femenino , Radioisótopos de Galio/química , Radioisótopos de Galio/uso terapéutico , Receptor del Péptido 1 Similar al Glucagón/análisis , Células HEK293 , Compuestos Heterocíclicos con 1 Anillo/química , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Humanos , Insulinoma/radioterapia , Ratones , Tomografía de Emisión de Positrones , Nanomedicina Teranóstica
8.
Angew Chem Int Ed Engl ; 58(41): 14758-14763, 2019 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-31429173

RESUMEN

Reactive oxygen species (ROS) can be used not only as a therapeutic agent for chemodynamic therapy (CDT), but also as a stimulus to activate release of antitumor drugs, achieving enhanced efficacy through the combination of CDT and chemotherapy. Here we report a pH/ROS dual-responsive nanomedicine consisting of ß-lapachone (Lap), a pH-responsive polymer, and a ROS-responsive polyprodrug. In the intracellular acidic environment, the nanomedicine can realize pH-triggered disassembly. The released Lap can efficiently generate hydrogen peroxide, which will be further converted into highly toxic hydroxyl radicals via the Fenton reaction. Subsequently, through ROS-induced cleavage of thioketal linker, doxorubicin is released from the polyprodrug. In vivo results indicate that the cascade of ROS generation and antitumor-drug release can effectively inhibit tumor growth. This design of nanomedicine with cascade reactions offers a promising strategy to enhance antitumor efficacy.


Asunto(s)
Antibióticos Antineoplásicos/química , Doxorrubicina/química , Naftoquinonas/química , Profármacos , Células A549 , Animales , Liberación de Fármacos , Humanos , Ratones , Nanopartículas , Neoplasias Experimentales/tratamiento farmacológico , Especies Reactivas de Oxígeno
9.
Mol Pharm ; 14(8): 2538-2547, 2017 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-28005375

RESUMEN

PHSCN peptide (licensed as ATN-161) is an effective α5ß1 integrin inhibitor that has advanced to phase II clinical trials to treat solid tumors. Here we developed ATN-161 functionalized self-cross-linkable and intracellularly de-cross-linkable polymersomes (ATN/SCID-Ps) for highly efficient and targeted delivery of doxorubicin hydrochloride (DOX·HCl) into B16F10 melanoma-bearing C57BL/6 mice. ATN/SCID-Ps exhibited a high loading capacity of DOX·HCl. The size of DOX-loaded ATN/SCID-Ps (DOX-ATN/SCID-Ps) decreased from 150 to 88 nm with increasing ATN surface densities from 0 to 100% (mol/mol). DOX-ATN/SCID-Ps were robust with low drug leakage under physiological conditions while quickly releasing DOX with the addition of 10 mM glutathione. MTT assay results displayed that DOX-ATN/SCID-Ps induced ATN density-dependent antitumor activity to α5ß1 integrin overexpressing B16F10 melanoma cells, in which 56% ATN-161 was optimal. Flow cytometry and CLSM studies revealed significantly more efficient internalization and cytoplasmic DOX release in B16F10 cells for DOX-ATN/SCID-Ps than for DOX-SCID-Ps (nontargeting control) as well as clinically used pegylated liposomal doxorubicin (DOX-LPs). DOX-ATN/SCID-Ps displayed a long blood circulation time (elimination half-life = 4.13 h) and 4 times higher DOX accumulation in B16F10 bearing C57BL/6 mice than DOX-LPs. Interestingly, DOX-ATN/SCID-Ps exhibited a superior maximum-tolerated dose of over 100 mg DOX·HCl/kg, 10 times higher than DOX-LPs. Remarkably, DOX-ATN/SCID-Ps could significantly inhibit the growth of aggressive B16F10 melanoma with little adverse effects via either multiple or single injection of total dosage of 100 mg DOX·HCl/kg, resulting in greatly improved survival rates as compared to DOX-LPs. ATN/SCID-Ps are appealing nanovehicles for targeted chemotherapy of α5ß1 integrin positive solid tumors.


Asunto(s)
Doxorrubicina/química , Doxorrubicina/uso terapéutico , Melanoma/tratamiento farmacológico , Péptidos/química , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Femenino , Citometría de Flujo , Semivida , Dosis Máxima Tolerada , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Biomacromolecules ; 16(6): 1726-35, 2015 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-25938556

RESUMEN

In spite of their high potency and specificity, few protein drugs have advanced to the clinical settings due to lack of safe and efficient delivery vehicles. Here, novel anisamide-decorated pH-sensitive degradable chimaeric polymersomes (Anis-CPs) were designed, prepared, and investigated for efficient and targeted delivery of apoptotic protein, granzyme B (GrB), to lung cancer cells. Anis-CPs were readily prepared with varying Anis surface densities from anisamide end-capped poly(ethylene glycol)-b-poly(2,4,6- trimethoxybenzylidene-1,1,1-tris(hydroxymethyl)ethane methacrylate)-b-poly(acrylic acid) (Anis-PEG-PTTMA-PAA) and PEG-PTTMA-PAA copolymers. Using cytochrome C (CC) as a model protein, Anis-CPs displayed high protein loading efficiencies (40.5-100%) and loading contents (up to 16.8 wt %). CC-loaded Anis-CPs had narrow distribution (PDI 0.04-0.13) and small sizes ranging from 152 to 171 nm, which increased with increasing CC contents. Notably, the release of proteins from Anis-CPs was accelerated under mildly acidic conditions, due to the hydrolysis of acetal bonds in PTTMA. MTT assays showed that GrB-loaded Anis-CPs (GrB-Anis-CPs) displayed high targetability to sigma receptor overexpressing cancer cells such as H460 and PC-3 cells. For example, GrB-Anis-CPs exhibited increasing antitumor efficacy to H460 cells with increasing Anis contents from 0 to 80%. The antitumor activity of GrB-Anis-CPs was significantly reduced upon pretreating H460 cells with haloperidol (a competitive antagonist). Notably, the half-maximal inhibitory concentrations (IC50) of GrB-Anis70-CPs were determined to be 6.25 and 5.94 nM for H460 and PC-3 cells, respectively, which were 2-3 orders of magnitude lower than that of chemotherapeutic drugs, such as paclitaxel. Flow cytometry studies demonstrated that GrB-Anis70-CPs induced widespread apoptosis of H460 cells. The confocal laser scanning microscopy (CLSM) experiments using FITC-labeled CC-loaded Anis-CPs confirmed fast internalization and intracellular protein release into H460 cells. GrB-Anis-CPs with high potency and specificity are particularly interesting for targeted therapy of lung cancers.


Asunto(s)
Benzamidas/química , Plásticos Biodegradables/química , Portadores de Fármacos/química , Células Epiteliales/efectos de los fármacos , Granzimas/administración & dosificación , Plásticos Biodegradables/síntesis química , Línea Celular Tumoral , Portadores de Fármacos/síntesis química , Granzimas/farmacología , Humanos , Metacrilatos/química , Polietilenglicoles/química
11.
Adv Sci (Weinh) ; 11(3): e2306580, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37984863

RESUMEN

Cancer immunotherapy has become a mainstream cancer treatment over traditional therapeutic modes. Cancer cells can undergo programmed cell death including ferroptosis, pyroptosis, autophagy, necroptosis, apoptosis and cuproptosis which are find to have intrinsic relationships with host antitumor immune response. However, direct use of cell death inducers or regulators may bring about severe side effects that can also be rapidly excreted and degraded with low therapeutic efficacy. Nanomaterials are able to carry them for long circulation time, high tumor accumulation and controlled release to achieve satisfactory therapeutic effect. Nowadays, a large number of studies have focused on nanomedicines-based strategies through modulating cell death modalities to potentiate antitumor immunity. Herein, immune cell types and their function are first summarized, and state-of-the-art research progresses in nanomedicines mediated cell death pathways (e.g., ferroptosis, pyroptosis, autophagy, necroptosis, apoptosis and cuproptosis) with immune response provocation are highlighted. Subsequently, the conclusion and outlook of potential research focus are discussed.


Asunto(s)
Apoptosis , Nanomedicina , Muerte Celular , Piroptosis , Autofagia
12.
Nat Commun ; 15(1): 5290, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38906865

RESUMEN

Long-term non-progressors (LTNPs) of HIV-1 infection may provide important insights into mechanisms involved in viral control and pathogenesis. Here, our results suggest that the ribosomal protein lateral stalk subunit P1 (RPLP1) is expressed at higher levels in LTNPs compared to regular progressors (RPs). Functionally, RPLP1 inhibits transcription of clade B HIV-1 strains by occupying the C/EBPß binding sites in the viral long terminal repeat (LTR). This interaction requires the α-helixes 2 and 4 domains of RPLP1 and is evaded by HIV-1 group M subtype C and group N, O and P strains that do not require C/EBPß for transcription. We further demonstrate that HIV-1-induced translocation of RPLP1 from the cytoplasm to the nucleus is essential for antiviral activity. Finally, knock-down of RPLP1 promotes reactivation of latent HIV-1 proviruses. Thus, RPLP1 may play a role in the maintenance of HIV-1 latency and resistance to RPLP1 restriction may contribute to the effective spread of clade C HIV-1 strains.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT , Infecciones por VIH , Duplicado del Terminal Largo de VIH , VIH-1 , Proteínas Ribosómicas , VIH-1/genética , VIH-1/metabolismo , VIH-1/fisiología , Humanos , Proteínas Ribosómicas/metabolismo , Proteínas Ribosómicas/genética , Duplicado del Terminal Largo de VIH/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/genética , Infecciones por VIH/virología , Infecciones por VIH/metabolismo , Infecciones por VIH/genética , Transcripción Genética , Unión Proteica , Latencia del Virus/genética , Sitios de Unión , Regulación Viral de la Expresión Génica , Células HEK293 , Núcleo Celular/metabolismo
13.
Adv Healthc Mater ; 13(16): e2303568, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319010

RESUMEN

High reactive oxygen species (ROS) levels in tumor microenvironment (TME) impair both immunogenic cell death (ICD) efficacy and T cell activity. Furthermore, tumor escapes immunosurveillance via programmed death-1/programmed death ligand-1 (PD-L1) signal, and the insufficient intracellular hydrogen peroxide weakens ferroptosis efficacy. To tackle the above issues, a glutathione (GSH)/ROS/pH triple-responsive prodrug nanomedicine that encapsulates Fe2O3 nanoparticle via electrostatic interaction is constructed for magnetic resonance imaging (MRI)-guided multi-mode theranostics with chemotherapy/ferroptosis/immunotherapy. The diselenide bond consumes ROS in TME to increase T cells and ICD efficacy, the cleavage of which facilitates PD-L1 antagonist D peptide release to block immune checkpoint. After intracellular internalization, Fe2O3 nanoparticle is released in the acidic endosome for MRI simultaneously with lipid peroxides generation for tumor ferroptosis. Doxorubicin is cleaved from polymers in the condition of high intracellular GSH level accompanied by tumor ICD, which simultaneously potentiates ferroptosis by NADPH oxidase mediated H2O2 self-generation. In vivo results indicate that the nanoplatform strengthens tumor ICD, induces cytotoxic T lymphocytes proliferation, inhibits 4T1 tumor regression and metastasis, and prolongs survival median. In all, a new strategy is proposed in strengthening ICD and T cells activity cascade with ferroptosis as well as immune checkpoint blockade for effective tumor immunotherapy.


Asunto(s)
Ferroptosis , Peróxido de Hidrógeno , Inmunoterapia , Profármacos , Especies Reactivas de Oxígeno , Peróxido de Hidrógeno/química , Profármacos/química , Profármacos/farmacología , Profármacos/uso terapéutico , Ferroptosis/efectos de los fármacos , Animales , Ratones , Especies Reactivas de Oxígeno/metabolismo , Inmunoterapia/métodos , Microambiente Tumoral/efectos de los fármacos , Humanos , Imagen por Resonancia Magnética/métodos , Polímeros/química , Línea Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacología , Nanopartículas/química , Ratones Endogámicos BALB C , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Femenino , Glutatión/metabolismo , Glutatión/química , Nanomedicina Teranóstica/métodos
14.
J Inflamm Res ; 17: 2697-2710, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38707955

RESUMEN

Recurrent spontaneous abortion (RSA) is defined as two or more consecutive pregnancy failures, which brings tremendous stress to women of childbearing age and seriously affects family well-being. However, the reason in about 50% of cases remains unknown and is defined as unexplained recurrent spontaneous abortion (URSA). The immunological perspective in URSA has attracted widespread attention in recent years. The embryo is regarded as a semi-allogeneic graft to the mother. A successful pregnancy requires transition to an immune environment conducive to embryo survival at the maternal-fetal interface. As an important member of regulatory immunity, regulatory T (Treg) cells play a key role in regulating immune tolerance at the maternal-fetal interface. This review will focus on the phenotypic plasticity and lineage stability of Treg cells to illustrate its relationship with URSA.

15.
Biomacromolecules ; 14(10): 3723-30, 2013 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-23998942

RESUMEN

The therapeutic performance of biodegradable micellar drugs is far from optimal due to existing challenges like poor tumor cell uptake and intracellular drug release. Here, we report on ligand-directed reduction-sensitive shell-sheddable biodegradable micelles based on poly(ethylene glycol)-poly(ε-caprolactone) (PEG-PCL) copolymer actively delivering doxorubicin (DOX) into the nuclei of target cancer cells, inducing superb in vitro antitumor effects. The micelles were constructed from PEG-SS-PCL and galactose-PEG-PCL (Gal-PEG-PCL) block copolymers, in which Gal-PEG-PCL was designed with a longer PEG than that in PEG-SS-PCL (6.0 vs 5.0 kDa) to fully expose Gal ligands onto the surface of micelles for effective targeting to hepatocellular carcinoma cells. PEG-SS-PCL combining with 10 or 20 wt % of Gal-PEG-PCL formed uniform micelles with average sizes of 56.1 and 58.2 nm (denoted as PEG-SS-PCL/Gal10 and PEG-SS-PCL/Gal20, respectively). The in vitro release studies showed that about 81.1 and 75.0% DOX was released in 12 h from PEG-SS-PCL/Gal10 and PEG-SS-PCL/Gal20 micelles under a reducing condition containing 10 mM dithiothreitol (DTT). In contrast, minimal DOX release (<12%) was observed for PEG-SS-PCL/Gal10 and PEG-SS-PCL/Gal20 micelles under nonreducing conditions as well as for reduction-insensitive Gal-PEG-PCL and PEG-PCL/Gal20 micelles in the presence of 10 mM DTT. MTT assays in HeLa and HepG2 cells showed that DOX-loaded PEG-SS-PCL/Gal20 micelles exhibited apparent targetability and significantly enhanced antitumor efficacy toward asialoglycoprotein receptor (ASGP-R)-overexpressing HepG2 cells with a particularly low half maximal inhibitory concentration (IC50) of 1.58 µg DOX equiv/mL, which was comparable to free DOX and approximately six times lower than that for nontargeting PEG-SS-PCL counterparts under otherwise the same conditions. Interestingly, confocal microscopy observations using FITC-labeled PEG-SS-PCL/Gal20 micelles showed that DOX was efficiently delivered and released into the nuclei of HepG2 cells in 8 h. Flow cytometry revealed that cellular DOX level in HepG2 cells treated with DOX-loaded PEG-SS-PCL/Gal20 micelles was much greater than that with reduction-insensitive PEG-PCL/Gal20 and nontargeting PEG-SS-PCL controls, signifying the importance of combining shell-shedding and active targeting. Ligand-directed, reduction-sensitive, shell-sheddable, and biodegradable micelles have emerged as a versatile and potent platform for targeted cancer chemotherapy.


Asunto(s)
Carcinoma Hepatocelular/patología , Núcleo Celular/metabolismo , Doxorrubicina/metabolismo , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Neoplasias Hepáticas/patología , Micelas , Antineoplásicos/administración & dosificación , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Ensayos de Selección de Medicamentos Antitumorales , Glicoles de Etileno/administración & dosificación , Glicoles de Etileno/química , Células Hep G2 , Humanos , Ligandos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Modelos Biológicos , Estructura Molecular , Oxidación-Reducción , Tamaño de la Partícula , Poliésteres/administración & dosificación , Poliésteres/química , Relación Estructura-Actividad , Propiedades de Superficie
16.
Pharmaceutics ; 15(3)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36986586

RESUMEN

Multiple sclerosis (MS) is an autoimmune-mediated demyelinating disease of the central nervous system. The main pathological features are inflammatory reaction, demyelination, axonal disintegration, reactive gliosis, etc. The etiology and pathogenesis of the disease have not been clarified. The initial studies believed that T cell-mediated cellular immunity is the key to the pathogenesis of MS. In recent years, more and more evidence has shown that B cells and their mediated humoral immune and innate immune cells (such as microglia, dendritic cells, macrophages, etc.) also play an important role in the pathogenesis of MS. This article mainly reviews the research progress of MS by targeting different immune cells and analyzes the action pathways of drugs. The types and mechanisms of immune cells related to the pathogenesis are introduced in detail, and the mechanisms of drugs targeting different immune cells are discussed in depth. This article aims to clarify the pathogenesis and immunotherapy pathway of MS, hoping to find new targets and strategies for the development of therapeutic drugs for MS.

17.
Vaccines (Basel) ; 11(9)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37766117

RESUMEN

Tumor vaccines have been used to treat cancer. How to efficiently induce tumor-associated antigens (TAAs) secretion with host immune system activation is a key issue in achieving high antitumor immunity. Immunogenic cell death (ICD) is a process in which tumor cells upon an external stimulus change from non-immunogenic to immunogenic, leading to enhanced antitumor immune responses. The immune properties of ICD are damage-associated molecular patterns and TAA secretion, which can further promote dendritic cell maturation and antigen presentation to T cells for adaptive immune response provocation. In this review, we mainly summarize the latest studies focusing on nanotechnology-mediated ICD for effective cancer immunotherapy as well as point out the challenges.

18.
Exp Ther Med ; 25(5): 235, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37114174

RESUMEN

Crocus sativus L. (saffron) is widely used as a traditional spice for flavoring, coloring and medicinal purposes. As a traditional Chinese herb, saffron promotes blood circulation, removes blood stasis, cools and detoxifies the blood, relieves depression and calms the mind. According to modern pharmacological studies, the active constituents of saffron, including crocetin, safranal and crocus aldehyde, exhibit antioxidant, anti-inflammatory, mitochondrial function-improving and antidepressant effects. Thus, saffron has the potential to treat neurodegenerative diseases (NDs) associated with oxidative stress, inflammation and impaired mitochondrial function, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and cerebral ischemia. The present article provides a review of the pharmacological effects of saffron and its constituents in terms of neuroprotective effects, including antioxidant and anti-inflammatory effects and the improvement of mitochondrial dysfunction, as well as their clinical application in treating NDs.

19.
Adv Healthc Mater ; 12(19): e2300260, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36905358

RESUMEN

As the first line of host defense against pathogenic infections, innate immunity plays a key role in antitumor immunotherapy. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) (cGAS-STING) pathway has attracted much attention because of the secretion of various proinflammatory cytokines and chemokines. Many STING agonists have been identified and applied into preclinical or clinical trials for cancer immunotherapy. However, the fast excretion, low bioavailability, nonspecificity, and adverse effects of the small molecule STING agonists limit their therapeutic efficacy and in vivo application. Nanodelivery systems with appropriate size, charge, and surface modification are capable of addressing these dilemmas. In this review, the mechanism of the cGAS-STING pathway is discussed and the STING agonists, focusing on nanoparticle-mediated STING therapy and combined therapy for cancers, are summarized. Finally, the future direction and challenges of nano-STING therapy are expounded, emphasizing the pivotal scientific problems and technical bottlenecks and hoping to provide general guidance for its clinical application.


Asunto(s)
Inmunidad Innata , Neoplasias , Humanos , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Neoplasias/terapia , Citocinas , Inmunoterapia
20.
Heliyon ; 9(8): e18969, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37636465

RESUMEN

Introduction: The increasing prevalence of carbapenem-resistant gram-negative bacilli infection has emerged as a substantial threat to human health. Methodology: In January 2017, a screening program for carbapenem-resistant gram-negative bacilli colonization was performed in a pediatric intensive care unit (PICU). Subsequently, different strategies for carbapenem-resistant gram-negative bacilli cohorting and patient placements were introduced in January 2018. Results: The increase in the single room isolation (type A) and the resettlement of the same area placement (type B) resulted in a significant decrease in the nosocomial infection rate from 2.57% (50/1945) in 2017 to 0.87% (15/1720) in 2021 (P < 0.001). Notably, the incidence of nosocomial carbapenem-resistant gram-negative bacilli infections decreased in 2019 (P = 0.046) and 2020 (P = 0.041) compared with that in the respective previous year. During 2019 and 2020, a statistically significant increasing trend of type A and type B placements was observed (P < 0.05, each), which may have contributed to the decline of carbapenem-resistant gram-negative bacilli infection. The primary carbapenemase genes identified in carbapenem-resistant isolates of Klebsiella pneumoniae and Acinetobacter baumannii were blaKPC-2 from sequence type 11 and blaOXA-23 from sequence type 1712. Conclusion: The integration of various placements for patients with carbapenem-resistant gram-negative bacilli infection with active screening has been demonstrated as an effective preventive strategy in the management of carbapenem-resistant gram-negative bacilli infection.

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