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1.
Biochem Biophys Res Commun ; 690: 149252, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995452

RESUMO

Alfalfa (Medicago sativa L.), a crucial and widely grown forage legume, faces yield and quality challenges due to salinity stress. The defender against apoptotic death (DAD) gene, recognized initially as an apoptosis suppressor in mammals, plays a pivotal role in catalyzing N-glycosylation, acting as a positive regulator for protein folding and endoplasmic reticulum (ER) export. Here, we found that the MsDAD2 gene was specially induced in the salt-tolerant alfalfa cultivar (DL) under salinity stress, but not in the salt-sensitive cultivar (SD). Overexpression of MsDAD2 enhanced the salinity resistance of transgenic alfalfa by promoting NAD(P)H-quinone oxidoreductase (NQO1) and cytochrome b6f complex subunit (Cyt b6/f) expression, thereby mitigating reactive oxygen species (ROS) production. ChIP-qPCR analysis suggested that the differential expression of MsDAD2 in DL and SD under salinity stress may be linked to dynamic histone modifications in its promoter. Therefore, our findings elucidate a novel regulatory mechanism of MsDAD2 in alfalfa's response to salinity stress, underscoring its significance as a target for alfalfa breeding to enhance salt tolerance.


Assuntos
Regulação da Expressão Gênica de Plantas , Medicago sativa , Medicago sativa/genética , Medicago sativa/metabolismo , Estresse Salino/genética , Tolerância ao Sal/genética , Salinidade
2.
Chemistry ; : e202400537, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703390

RESUMO

With the popularization of 5G technology and artificial intelligence, thermally conductive epoxies with self-healing ability will be widely used in flexible electronic materials. Although many compounds containing both performances have been synthesized, there is little systematic theory to explain the coordination mechanism. In this paper, alkyl chains of different lengths were introduced to epoxies to discuss the thermally conductive, the self-healing performance, and the synergistic effect. A series of electronic-grade biphenyl epoxies (4,4'-bis(oxiran-2-ylmethoxy)-1,1'-biphenyl (1), 4,4'-bis(2-(oxiran-2-yl)ethoxy)-1,1'-biphenyl (2), 4,4'-bis(3-(oxiran-2-yl)propoxy)-1,1'-biphenyl (3), and 4,4'-bis(4-(oxiran-2-yl)butoxy)-1,1'-biphenyl (4) were synthesized and characterized. Furthermore, they were cured with decanedioic acid to produce polymers. Results showed that alkyl chains can both affect the two properties, and the epoxies suitable for specific application scenarios can be prepared by adjusting the length of alkyl chains. In terms of thermal conductivity, compound 1 was a most promising material. However, compound 4 was expected to be utilized in flexible electronic devices because of its acceptable thermal conductivity, self-healing ability, transparency, and flexibility.

3.
Fish Shellfish Immunol ; 135: 108631, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36907480

RESUMO

To investigate the effects of adding different concentrations of cup plant (Silphium perfoliatum L.) to the feed on the growth performance, hepatopancreas and intestinal microstructure, gene expression, enzyme activity, as well as intestinal microorganisms and resistance to Vibrio parahaemolyticus E1 and White spot syndrome virus (WSSV) infection of the shrimp, cup plant was added to the basal feed at 1%, 3%, 5% and 7% respectively, and fed the shrimp for 6 weeks. It was found that the addition of different concentrations of cup plant could significantly improve the specific growth rate and survival rate of shrimp, reduce the feed conversion rate, and improve the resistance to V. parahaemolyticus E1 and WSSV in shrimp, with the best effect of 5% addition. The tissue sections observations showed that the addition of cup plant significantly improved the hepatopancreas and intestinal tissues of shrimp, especially in alleviating the tissue damage caused by V. parahaemolyticus E1 and WSSV infection, but too high an addition (7%) could also cause side effects on the shrimp intestinal tract. Meantime, the addition of cup plant can also increase the activity of immunodigestive-related enzymes in the hepatopancreas and intestinal tissues of shrimp, and can significantly induce the up-regulation of immune-related genes expression, and it is positively correlated with the amount of addition in a certain range. In addition, it was found that the addition of cup plant has a significant regulating effect on the intestinal flora of shrimp, which can significantly promote the growth of beneficial bacteria such as Haloferula sp., Algoriphagus sp. and Coccinimonas sp., and inhibit pathogenic bacteria Vibrio sp., such as the number of Vibrionaceae_Vibrio and Pseudoalteromonadaceae_Vibrio in the experimental group were significantly reduced, and the lowest level in the 5% addition group. In summary, the study shows that cup plant can promote the growth of shrimp, improve the resistance of shrimp to disease, and is a potential green environmental feed additive that can replace antibiotics.


Assuntos
Asteraceae , Microbioma Gastrointestinal , Penaeidae , Vibrio parahaemolyticus , Vírus da Síndrome da Mancha Branca 1 , Animais , Resistência à Doença , Imunidade Inata/genética , Vibrio parahaemolyticus/fisiologia , Vírus da Síndrome da Mancha Branca 1/fisiologia
4.
Int J Syst Evol Microbiol ; 70(11): 5943-5949, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33016859

RESUMO

A novel Gram-stain-negative, strictly aerobic, rod-shaped, brick red-pigmented bacterium, designated R-22-1 c-1T, was isolated from water from Baiyang Lake, Hebei Province, PR China. The strain was able to grow at 20-30 °C (optimum, 30 °C) and pH 6-7 (optimum, pH 6) in Reasoner's 2A medium. 16S rRNA gene sequence and phylogenetic analyses of R-22-1 c-1T revealed closest relationships to Rufibacter immobilis MCC P1T (97.8 %), Rufibacter sediminis H-1T (97.9 %) and Rufibacter glacialis MDT1-10-3T (97.0 %), with other species of the genus Rufibacter showing less than 97.0 % sequence similarity. The predominant polar lipids were phosphatidylethanolamine, two unidentified aminophospholipids and three unidentified lipids. The major cellular fatty acids were iso-C15 : 0, C15 : 1 ω6c, C17 : 1 ω6c, anteiso-C15 : 0, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 4 (iso-C17 : 1I and/or anteiso-C17 : 1B). The respiratory quinone was MK-7. The draft genome of R-22-1 c-1T was 5.6 Mbp in size, with a G+C content of 50.2 mol%. The average nucleotide identity and digital DNA-DNA hybridization relatedness values between strain R-22-1 c-1T and related type strains were R. immobilis MCC P1T (77.2 and 21.8 %), R. sediminis H-1T (81.6 and 21.4 %) and R. tibetensis 1351T (78.5 and 22.9 %). Based on these phylogenetic, chemotaxonomic and genotypic results, strain R-22-1 c-1T represents a novel species in the genus Rufibacter, for which the name Rufibacter latericius sp. nov. is proposed. The type strain is R-22-1 c-1T (=CGMCC 1.13570T=KCTC 62781T).


Assuntos
Bacteroidetes/classificação , Lagos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Int J Syst Evol Microbiol ; 69(12): 3676-3681, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31135333

RESUMO

A novel Gram-stain-negative, strictly aerobic, rod-shaped, gray-pigmented bacterial strain, designated L-25-5 w-1T, was isolated from the water at Baiyang Lake, PR China. Cells of strain L-25-5 w-1T were motile, with a single polar flagellum. L-25-5 w-1T was able to grow at 15-37 °C (optimum 37 °C) and pH 5-8 (optimum pH 6) in R2A medium. 16S rRNA gene sequence analysis and phylogenetic analysis of L-25-5 w-1T showed the highest relationship to Azospirillum doebereinerae GSF71T (97.9 %), Azospirillum thiophilum DSM 21654T (97.9 %) and Azospirillum agricola CC-HIH038T (97.0 %), with other species of the genus Azospirillum showing less than 97 % sequence similarity. The predominant polar lipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol and two unidentified aminolipids; the major cellular fatty acids were C16 : 0, C16 : 0 3-OH, C18 : 1 2-OH, iso-C18 : 0, summed feature 2 (C12 : 0 aldehyde and/or unknown 10.9525 and/or iso-C16 : 1I and/or C14 : 0 3-OH), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c); and the major respiratory quinone was ubiquinone 10. The draft genome size of L-25-5 w-1T was 5.8 Mbp, and the DNA G+C content was 66.6 %. The average nucleotide identity value and digital DNA-DNA hybridization relatedness value between L-25-5 w-1T and related type strains were 80.2 and 24.7 % with A. doebereinerae GSF71T and 78.8 and 23.6 % with A. thiophilum DSM 21654T, respectively. According to the phylogenetic, chemotaxonomic and genotypic properties, strain L-25-5 w-1T represents a novel species in the genus Azospirillum, for which the name Azospirillum griseum sp. nov. is proposed. The type strain is L-25-5 w-1T (=CGMCC 1.13672T=KCTC 62777T).


Assuntos
Azospirillum/classificação , Lagos/microbiologia , Filogenia , Azospirillum/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
6.
Small ; 10(13): 2678-87, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24668891

RESUMO

Drug resistance is the greatest challenge in clinical cancer chemotherapy. Co-delivery of chemotherapeutic drugs and siRNA to tumor cells is a vital means to silence drug resistant genes during the course of cancer chemotherapy for an improved chemotherapeutic effect. This study aims at effective co-delivery of siRNA and anticancer drugs to tumor cells. A ternary block copolymer PEG-PAsp(AED)-PDPA consisting of pH-sensitive poly(2-(diisopropyl amino)ethyl methacrylate) (PDPA), reduction-sensitive poly(N-(2,2'-dithiobis(ethylamine)) aspartamide) PAsp(AED), and poly(ethylene glycol) (PEG) is synthesized and assembled into a core-shell structural micelle which encapsulated doxorubicin (DOX) in its pH-sensitive core and the siRNA-targeting anti-apoptosis BCL-2 gene (BCL-2 siRNA) in a reduction-sensitive interlayer. At the optimized size and zeta potential, the nanocarriers loaded with DOX and BCL-2 siRNA may effectively accumulate in the tumor site via blood circulation. Moreover, the dual stimuli-responsive design of micellar carriers allows microenviroment-specific rapid release of both DOX and BCL-2 siRNA inside acidic lysosomes with enriched reducing agent, glutathione (GSH, up to 10 mM). Consequently, the expression of anti-apoptotic BCL-2 protein induced by DOX treatment is significantly down-regulated, which results in synergistically enhanced apoptosis of human ovarian cancer SKOV-3 cells and thus dramatically inhibited tumor growth.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Concentração de Íons de Hidrogênio , Nanotecnologia , Neoplasias/terapia , RNA Interferente Pequeno/administração & dosagem , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Microscopia Eletrônica de Transmissão
7.
Int J Nanomedicine ; 19: 1145-1161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344438

RESUMO

Introduction: Spatiotemporally controlled release of siRNA for anti-tumor therapy poses significant challenges. Near-infrared (NIR) light, known for its exceptional tissue penetration and minimal tissue invasiveness, holds promise as a viable exogenous stimulus for inducing controlled siRNA release in vivo. However, the majority of light-responsive chemical bonds exhibit absorption wavelengths in the ultraviolet (UV) or short-wavelength visible light range. Methods: To achieve NIR-controlled siRNA release, the study synthesized a UV-sensitive triblock copolymer cRGD-poly(ethylene glycol)-b-poly(aspartic acid ester-5-(2'-(dimethylamino)ethoxy)-2-nitrobenzyl alcohol)-b-polyphenylalanine, abbreviated as cRGD-PEG-PAsp(EDONB)-PPHE. This copolymer is composed of a cRGD-capped PEG block (cRGD-PEG), a poly(aspartate) block modified with cationic moieties through UV-cleavable 2-nitrobenzyl ester bonds [PAsp(EDONB)], and a hydrophobic polyphenylalanine block (PPHE). The cationic amphiphilic polymer cRGD-PEG-PAsp(EDONB)-PPHE can assemble with hydrophobic upconversion nanoparticles (UCNPs) to form a cationic micelle designated as T-UCNP, which subsequently complexes with siRNA to create the final nanopolyplex T-si/UCNP. siRNA-PLK1 was employed to prepare T-PLK1/UCNP nanopolyplex for anti-tumor therapy. Results: T-PLK1/UCNP not only exhibited outstanding tumor cell targeting through cRGD modification but also achieved 980 nm NIR-controlled PLK1 gene silencing. This was achieved by utilizing the encapsulated UCNPs to convert NIR into UV light, facilitating the cleavage of 2-nitrobenzyl ester bonds. As a result, there was a significant suppression of tumor growth. Conclusion: The UCNPs-encapsulated nanopolyplex T-si/UCNP, capable of co-delivering siRNA and UCNPs, enables precise NIR-controlled release of siRNA at the tumor site for cancer RNAi therapy. This nanopolyplex can enhance the controllability and safety of RNAi therapy for tumors, and it also holds the potential to serve as a platform for achieving controlled release and activation of other drugs, such as mRNA and DNA.


Assuntos
Nanopartículas , Neoplasias , Animais , RNA Interferente Pequeno/genética , Preparações de Ação Retardada/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Polímeros , Modelos Animais , Ésteres
8.
J Control Release ; 372: 403-416, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38914207

RESUMO

The immunosuppressive microenvironment of malignant tumors severely hampers the effectiveness of anti-tumor therapy. Moreover, abnormal tumor vasculature interacts with immune cells, forming a vicious cycle that further interferes with anti-tumor immunity and promotes tumor progression. Our pre-basic found excellent anti-tumor effects of c-di-AMP and RRx-001, respectively, and we further explored whether they could be combined synergistically for anti-tumor immunotherapy. We chose to load these two drugs on PVA-TSPBA hydrogel scaffolds that expressly release drugs within the tumor microenvironment by in situ injection. Studies have shown that c-di-AMP activates the STING pathway, enhances immune cell infiltration, and reverses tumor immunosuppression. Meanwhile, RRx-001 releases nitric oxide, which increases oxidative stress injury in tumor cells and promotes apoptosis. Moreover, the combination of the two presented more powerful pro-vascular normalization and reversed tumor immunosuppression than the drug alone. This study demonstrates a new design option for anti-tumor combination therapy and the potential of tumor environmentally responsive hydrogel scaffolds in combination with anti-tumor immunotherapy.

9.
Rev Neurosci ; 24(4): 443-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23907421

RESUMO

The extracellular matrix (ECM) is the naturally occurring substrate that provides a support structure and an attachment site for cells. It also produces a biological signal, which plays an important role in and has significant impact on cell adhesion, migration, proliferation, differentiation, and gene expression. Peripheral nerve repair is a complicated process involving Schwann cell proliferation and migration, 'bands of Büngner' formation, and newborn nerve extension. In the ECM of peripheral nerves, macromolecules are deposited among cells; these constitute the microenvironment of Schwann cell growth. Such macromolecules include collagen (I, III, IV, V), laminin, fibronectin, chondroitin sulfate proteoglycans (CSPGs), and other nerve factors. Collagen, the main component of ECM, provides structural support and guides newborn neurofilament extension. Laminin, fibronectin, CSPGs, and neurotrophic factors, are promoters or inhibitors, playing different roles in nerve repair after injury. By a chemical decellularization process, acellular nerve allografting eliminates the antigens responsible for allograft rejection and maintains most of the ECM components, which can effectively guide and enhance nerve regeneration. Thus, the composition and features of peripheral nerve ECM suggest its superiority as nerve repair material. This review focuses on the structure, function, and application in the tissue engineering nerve construction of the peripheral nerve ECM components.


Assuntos
Matriz Extracelular/metabolismo , Regeneração Nervosa/fisiologia , Nervos Periféricos/metabolismo , Engenharia Tecidual/métodos , Animais , Humanos , Traumatismos dos Nervos Periféricos/terapia
10.
Int J Nanomedicine ; 18: 3663-3694, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37427368

RESUMO

Glioblastoma (GBM), a highly aggressive form of brain cancer, is considered one of the deadliest cancers, and even with the most advanced medical treatments, most affected patients have a poor prognosis. However, recent advances in nanotechnology offer promising avenues for the development of versatile therapeutic and diagnostic nanoplatforms that can deliver drugs to brain tumor sites through the blood-brain barrier (BBB). Despite these breakthroughs, the use of nanoplatforms in GBM therapy has been a subject of great controversy due to concerns over the biosafety of these nanoplatforms. In recent years, biomimetic nanoplatforms have gained unprecedented attention in the biomedical field. With advantages such as extended circulation times, and improved immune evasion and active targeting compared to conventional nanosystems, bionanoparticles have shown great potential for use in biomedical applications. In this prospective article, we endeavor to comprehensively review the application of bionanomaterials in the treatment of glioma, focusing on the rational design of multifunctional nanoplatforms to facilitate BBB infiltration, promote efficient accumulation in the tumor, enable precise tumor imaging, and achieve remarkable tumor suppression. Furthermore, we discuss the challenges and future trends in this field. Through careful design and optimization of nanoplatforms, researchers are paving the way toward safer and more effective therapies for GBM patients. The development of biomimetic nanoplatform applications for glioma therapy is a promising avenue for precision medicine, which could ultimately improve patient outcomes and quality of life.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Sistemas de Liberação de Medicamentos/métodos , Estudos Prospectivos , Qualidade de Vida , Glioma/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia
11.
Pharmaceutics ; 15(4)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37111692

RESUMO

Abnormal tumor vasculature and a hypoxic tumor microenvironment (TME) limit the effectiveness of conventional cancer treatment. Recent studies have shown that antivascular strategies that focus on antagonizing the hypoxic TME and promoting vessel normalization effectively synergize to increase the antitumor efficacy of conventional therapeutic regimens. By integrating multiple therapeutic agents, well-designed nanomaterials exhibit great advantages in achieving higher drug delivery efficiency and can be used as multimodal therapy with reduced systemic toxicity. In this review, strategies for the nanomaterial-based administration of antivascular therapy combined with other common tumor treatments, including immunotherapy, chemotherapy, phototherapy, radiotherapy, and interventional therapy, are summarized. In particular, the administration of intravascular therapy and other therapies with the use of versatile nanodrugs is also described. This review provides a reference for the development of multifunctional nanotheranostic platforms for effective antivascular therapy in combined anticancer treatments.

12.
Mater Today Bio ; 23: 100839, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38024837

RESUMO

STING (Stimulator of Interferon Genes) agonists have emerged as promising agents in the field of cancer immunotherapy, owing to their excellent capacity to activate the innate immune response and combat tumor-induced immunosuppression. This review provides a comprehensive exploration of the strategies employed to develop effective formulations for STING agonists, with particular emphasis on versatile nano-delivery systems. The recent advancements in delivery systems based on lipids, natural/synthetic polymers, and proteins for STING agonists are summarized. The preparation methodologies of nanoprecipitation, self-assembly, and hydrogel, along with their advantages and disadvantages, are also discussed. Furthermore, the challenges and opportunities in developing next-generation STING agonist delivery systems are elaborated. This review aims to serve as a reference for researchers in designing novel and effective STING agonist delivery systems for cancer immunotherapy.

13.
RSC Adv ; 12(33): 21609-21620, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35975058

RESUMO

The therapeutic effect of photodynamic therapy (PDT) is highly dependent on the intracellular production of reactive oxygen species (ROS). However, the ROS generated by photosensitizers can be consumed by the highly concentrated glutathione (GSH) in tumor cells, severely impairing the therapeutic effect of PDT. Herein, we synthesized a GSH-scavenging copolymer to deliver photosensitizer chlorin e6 (Ce6). The pyridyl disulfide groups, which have faster reactivity with the thiol groups of GSH than other disulfide groups, were grafted onto a hydrophobic block to encapsulate the Ce6. Under NIR irradiation, the Ce6 generated ROS to kill tumor cells, and the pyridyl disulfide groups depleted the GSH to prevent ROS consumption, which synergistically enhanced the therapeutic effect of PDT. In vitro and in vivo experiments confirmed the combinatory antitumor effect of Ce6-induced ROS generation and the pyridyl disulfide group-induced GSH depletion. Therefore, the pyridyl disulfide group-grafted amphiphilic copolymer provides a more efficient strategy for enhancing PDT and has promising potential for clinical application.

14.
Biomater Sci ; 10(15): 4170-4183, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35726827

RESUMO

Although CuO-deposited bovine serum albumin (CuO-BSA) and glucose oxidase (GOx) were combined to achieve H2O2 self-supplied chemo-dynamic therapy (CDT) and glucose consumption-based starvation therapy, the uses of copper and GOx have not been optimized to enhance tumour-selective reactive oxygen species (ROS) generation and minimize toxicity to normal cells as well. Here, chemo-dynamic nanoparticles (CBGP NPs) were prepared through a facile biomineralization process and subsequent coatings with GOx and the cationic polymer PEG2k-PEI1.8k. Through optimizing the use of copper, GOx, and PEG2k-PEI1.8k, the CBGP NPs showed high cellular uptake efficiency, enhanced tumour-selective ROS generation, and minimal side effects toward normal cells. The CBGP NP-mediated glucose consumption, GSH-depletion, and ˙OH generation synergistically induced tumour cell apoptosis both in vitro and in vivo. It is believed that the optimized CBGP NPs can be a promising nanoplatform for effective tumour therapy with minimal side effects.


Assuntos
Glioma , Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Cobre , Glioma/tratamento farmacológico , Glucose , Glucose Oxidase/farmacologia , Peróxido de Hidrogênio , Camundongos , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio
15.
Acta Biomater ; 137: 238-251, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653697

RESUMO

Semiconducting polymer (SP) is a promising photothermal agent in the antitumor application, but the co-delivery of the second near-infrared window (NIR-II)-based SPs with chemotherapeutic drug (e.g., doxorubicin (DOX)) remains a challenge. Here, SPs were firstly improved via backbone and alkyl side-chain engineering, and afterward, SPs and pH-sensitive prodrug copolymer self-assembled into a nanoparticle for a photoacoustic (PA)-imaging guided combination of photothermal therapy and chemotherapy. SP-encapsulated nanoparticles exhibited a high photothermal conversion efficiency of 45% at a relatively low power level of NIR irradiation (0.3 W/cm2 for 5 min). DOX was rapidly released in response to the acidic lysosomal environment. PA and fluorescence imaging confirmed that the photothermal therapy effectively drove DOX penetration inside tumor tissue, and it resulted in the killing of the surviving tumor cells from hyperthermia. The synergistic effect of SP-based photothermal therapy and DOX-induced chemotherapy was verified in vivo. Overall, the co-delivery of the SP and DOX using pH-sensitive nanoparticles represents a feasible strategy for photothermal therapy with potentially synergistic drug effects. STATEMENT OF SIGNIFICANCE: Recent years have yielded great progress in semiconducting polymers (SPs)-based photothermal therapy for anticancer treatment. However, studies about molecular weight and side-chain of SPs on photothermal conversion efficiency are limited, and investigation of controlled codelivery with chemotherapeutic drug is lacking. Here, we improved the SPs performance via backbone and side-chain engineering, and afterward offered a pH-sensitive DOX-conjugated amphiphilic copolymer to encapsulate SPs. SP-encapsulated nanoparticles exhibited high photothermal conversion efficiency at a clinically feasible power level of NIR irradiation. NIR irradiation-generated hyperthermia not only killed tumor cells but also promoted DOX penetration inside the tumor tissue to ablate the tumor cells that survived hyperthermia. The synergistic effect of SP-based photothermal therapy and DOX-induced chemotherapy was verified in vivo.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Pró-Fármacos , Células A549 , Animais , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Camundongos Nus , Fototerapia , Polímeros , Pró-Fármacos/farmacologia
16.
ACS Appl Mater Interfaces ; 14(50): 55376-55391, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36503225

RESUMO

Global pandemics caused by viruses cause widespread panic and economic losses. The lack of specific antivirals and vaccines increases the spreading of viral diseases worldwide. Thus, alternative strategies are required to manage viral outbreaks. Here, we develop a CRISPR activation (CRISPRa) system based on polymeric carriers to prevent respiratory virus infection in a mouse model. A polyaspartate grafted with 2-(diisopropylamino) ethylamine (DIP) and nuclear localization signal peptides (NLS-MTAS fusion peptide) was complexed with plasmid DNA (pDNA) encoding dCas9-VPR and sgRNA targeting IFN-λ. The pH-sensitive DIP and NLS-MTAS groups were favor of endo-lysosomal escape and nuclear localization of pDNA, respectively. They synergistically improved gene transfection efficiency, resulting in significant reporter gene expression and IFN-λ upregulation in lung tissue. In vitro and in vivo prophylactic experiments showed that the non-viral CRISPRa system could prevent infection caused by H1N1 viruses with minimal inflammatory responses, presenting a promising prophylactic approach against respiratory virus infections.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Interferon lambda , Animais , Camundongos , Transfecção , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Vírus da Influenza A Subtipo H1N1/genética , Peptídeos/metabolismo , DNA/metabolismo , Sinais de Localização Nuclear/genética , Sinais de Localização Nuclear/metabolismo
18.
Artif Organs ; 35(12): 1151-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21951229

RESUMO

Clinically, the current transcatheter aortic valve (TAV) technology has shown a propensity for paravalvular leakage; studies have correlated this flaw to increased calcification at the implantation site and with nonideal geometry of the stented valve. The present study evaluated the hydrodynamics of different geometric configurations, in particular the intravalvular considerations. Three TAV devices were made to create a representative, size 26 mm TAV. Hydrodynamics were assessed using a pulse duplicator. The geometries tested were composed of the nominal, elliptical, triangular, and undersized shapes; along with half-constriction, a conformation in which only a portion of the stent was constrained. The TAVs were assessed for transvalvular pressure gradient (TVG), effective orifice area (EOA), and regurgitant fraction. The nominal-sized shape posed a larger TVG (6.2 ± 0.3 mm Hg) than other configurations (P < 0.001) except the undersized valves. EOA of the nominal sized TAV (1.7 ± 0.1 cm(2) ) was smaller than that of the triangular and half-elliptical versions (P < 0.001). The half- and full-undersized geometries had EOAs smaller than the nominal type (P < 0.001). Nominal shape had smaller regurgitation (6.7 ± 1.4%) than all configurations (P < 0.001) except for the half-undersized (4.0 ± 0.7, P < 0.001) with no statistically significant difference from the full-undersized (6.8 ± 1.3, P = 0.724). The testing of variable geometries showed significant differences from the nominal geometry with respect to TVG, EOA, and regurgitant fraction. In particular, many of these nonideal configurations demonstrated an increased intravalvular regurgitation.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Hidrodinâmica , Animais , Bovinos , Humanos , Desenho de Prótese , Falha de Prótese
19.
Front Nutr ; 8: 745272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631772

RESUMO

[This corrects the article DOI: 10.3389/fnut.2021.645416.].

20.
J Mater Chem B ; 9(30): 6044-6055, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34269356

RESUMO

The controllable degradation of silica nanoparticles in anticancer therapy remains challenging. Here, we offer the first report that a thioketal (TK)-bond-containing bridged organoalkoxysilane has been synthesized. This allows for the fabrication of reactive oxygen species (ROS)-sensitive, degradable, bridged silsesquioxane nanoparticles (BS-NPs). These TK-bridged BS-NPs have a uniform size of 50 nm and are able to encapsulate a small molecule drug - metformin - using a reverse micro-emulsion method. After surface modification with a targeting peptide (RGD), these metformin-loaded BS-NPs exhibited a homologous tumor aggregation ability, leading to the efficient transport of metformin into the tumor cells. When combined with a clinically feasible fasting therapy, the RGD-decorated, metformin-loaded, ROS-responsive degradable BS-NPs remarkably increased the tumor sensitivity to metformin by 10 times compared with free metformin. The synergistic effects of metformin-loaded BS-NPs and fasting-induced hypoglycemia were verified through in vitro and in vivo experiments. This effect occurred by down-regulating the expression of pro-survival proteins pGSK3ß and MCL-1. Collectively, these results demonstrate that the ROS-sensitive organosilica nanocarrier is a promising nanoplatform for drug delivery and provides an alternative approach for the combinatorial therapy of metformin and fasting therapy.


Assuntos
Antineoplásicos/farmacologia , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Nanopartículas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HeLa , Humanos , Hipoglicemia/metabolismo , Hipoglicemia/patologia , Hipoglicemiantes/química , Hipoglicemiantes/metabolismo , Metformina/química , Metformina/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Dióxido de Silício/química
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