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1.
Small ; 20(29): e2400666, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38368259

RESUMO

Compared to conventional radiotherapy (RT), FLASH-RT delivers ultra-high dose radiation, significantly reducing damage to normal tissue while guaranteeing the effect of cancer treatment. However, cancer recurrence and metastasis frequently occur after all RT due to the existence of intractable cancer stem cells (CSCs). To address this, a biomimetic nanoplatform (named TAFL) of tumor-derived exosome fusion liposomes is designed by co-loading aggregation-induced emission photothermal agents, TPE-BBT, and anti-cancer drugs, aspirin, aiming to clear CSCs for inhibiting cancer recurrence and metastasis after FLASH-RT therapy . Aspirin released in TAFL system triggered by laser irradiation can induce apoptosis and DNA damage of 4T1 CSCs, comprehensively downregulate their stemness phenotype, and inhibit their sphericity. Furthermore, the TPE-BBT mediated mild-photothermal therapy can alleviate the hypoxic tumor microenvironment, inhibit the DNA repair of CSCs, which further amplifies the effect of aspirin against CSCs, therefore reduces the effective dose of aspirin, making TAFL more biologically safe. In vivo experimental results demonstrated that decreased CSCs population mediated by TAFL system treatment significantly inhibited tumor recurrence and metastasis after FLASH-RT therapy. In summary, this TAFL system   provides a new idea for the future clinical application of FLASH-RT therapy.


Assuntos
Aspirina , Neoplasias da Mama , Metástase Neoplásica , Células-Tronco Neoplásicas , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Animais , Feminino , Aspirina/farmacologia , Aspirina/uso terapêutico , Linhagem Celular Tumoral , Recidiva Local de Neoplasia , Camundongos , Humanos , Dano ao DNA , Microambiente Tumoral/efeitos dos fármacos , Lipossomos/química , Apoptose/efeitos dos fármacos , Biomimética/métodos , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Exossomos/metabolismo
2.
J Environ Manage ; 353: 120148, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38306856

RESUMO

Arsenic-bearing neutralization (ABN) sludge is a classical hazardous waste commonly found in nonferrous metallurgy. However, the current storage of these hazardous wastes not only has to pay costly hazardous waste taxes but also poses significant risks to both the environment and human health. To address these issues and achieve the comprehensive utilization and minimization of ABN sludge, this study proposes a new combined process. The process involves selective reduction roasting, leaching, and carbonation, through which, the arsenate and gypsum in the ABN sludge were recovered in the form of As(s), high-purity CaCO3, and H2S. The selective reduction behaviors of arsenate and gypsum were investigated through thermodynamic analysis and roasting experiments. The results indicated that the 95.35 % arsenate and 96.55 % gypsum in the sludge were selectively reduced to As4(g) and CaS at 950 °C by carbothermic reduction. The As4(g) was condensed to As(s) and enriched in the dust (As, 96.78 wt %). In the leaching process, H2S gas was adopted to promote the leaching of CaS, and resulted in 97.41 % of CaS in the roasted product was selectively leached in the form of Ca(HS)2, leading to a 74.11 % reduction in the weight of the ABN sludge. Then, the Ca(HS)2 was subjected to capture CO2 for the separation of Ca2+ and S2-. The result depicted that 99.69 % of Ca2+ and 99.12 % of S2- were separated as high-purity (99.12 wt %) CaCO3 and H2S (24.89 vol %) by controlling the terminal carbonation pH to below 6.55. The generated H2S can be economically converted to sulfur by the Clause process. The whole process realized the comprehensive resource recovery and the minimization of the sludge, which provides an alternative solution for the clean treatment of hazardous ABN waste.


Assuntos
Arsênio , Humanos , Arsênio/análise , Esgotos , Arseniatos , Sulfato de Cálcio , Resíduos Perigosos
3.
Learn Mem ; 30(12): 325-337, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38114331

RESUMO

Memory retrieval is strikingly susceptible to external states (environment) and internal states (mood states and alcohol), yet we know little about the underlying mechanisms. We examined how internally generated states influence successful memory retrieval using the functional magnetic resonance imaging (fMRI) of laboratory mice during memory retrieval. Mice exhibited a strong tendency to perform memory retrieval correctly only in the reinstated mammillary body-inhibited state, in which mice were trained to discriminate auditory stimuli in go/no-go tasks. fMRI revealed that distinct auditory cues engaged differential brain regions, which were primed by internal state. Specifically, a cue associated with a reward activated the lateral amygdala, while a cue signaling no reward predominantly activated the postsubiculum. Modifying these internal states significantly altered the neural activity balance between these regions. Optogenetic inhibition of those regions in the precue period blocked the retrieval of type-specific memories. Our findings suggest that memory retrieval is under the control of two interrelated neural circuits underlying the neural basis of state-dependent memory retrieval.


Assuntos
Encéfalo , Memória , Camundongos , Animais , Memória/fisiologia , Encéfalo/fisiologia , Sinais (Psicologia) , Mapeamento Encefálico , Imageamento por Ressonância Magnética
4.
Ecotoxicol Environ Saf ; 262: 115202, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37390726

RESUMO

Fungi are considered among the most efficient microbial degraders of plastics, as they produce salient enzymes and can survive on recalcitrant compounds with limited nutrients. In recent years, studies have reported numerous species of fungi that can degrade different types of plastics, yet there remain many gaps in our understanding of the processes involved in biodegradation. In addition, many unknowns need to be resolved regarding the fungal enzymes responsible for plastic fragmentation and the regulatory mechanisms which fungi use to hydrolyse, assimilate and mineralize synthetic plastics. This review aims to detail the main methods used in plastic hydrolysis by fungi, key enzymatic and molecular mechanisms, chemical agents that enhance the enzymatic breakdown of plastics, and viable industrial applications. Considering that polymers such as lignin, bioplastics, phenolics, and other petroleum-based compounds exhibit closely related characteristics in terms of hydrophobicity and structure, and are degraded by similar fungal enzymes as plastics, we have reasoned that genes that have been reported to regulate the biodegradation of these compounds or their homologs could equally be involved in the regulation of plastic degrading enzymes in fungi. Thus, this review highlights and provides insight into some of the most likely regulatory mechanisms by which fungi degrade plastics, target enzymes, genes, and transcription factors involved in the process, as well as key limitations to industrial upscaling of plastic biodegradation and biological approaches that can be employed to overcome these challenges.

5.
J Environ Manage ; 331: 117256, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36642046

RESUMO

A novel process that includes selective reduction roasting followed by hydrolysis was proposed in this work to recover zinc, and efficiently extract calcium and sulfur from hazardous zinc-rich gypsum residue (ZGR) waste for high-purity of CaCO3 and sulfur production. The selective reduction behaviors of ZGR during the reduction roasting were investigated in detail based on thermodynamic analysis and roasting experiments. The effect of roasting temperature, carbon dosage and time on the selective reduction of ZGR was comprehensively investigated, and the results indicated that ZnO and CaSO4 in the ZGR can be selectively reduced to Zn(g) and CaS, respectively. The volatile Zn(g) was oxidized to ZnO and enriched in the dust, which can be used as a secondary zinc resource. Moreover, the hydrolysis behaviors and leaching kinetic of CaS during hydrolysis were studied intensively. Results depicted that in the H2S-H2O system, the CaS in the roasted product can be selectively and efficiently dissolved into the leachate. Furthermore, the kinetic analysis revealed that the hydrolysis of CaS conformed to the internal diffusion reaction control model in the shrinking core model and the apparent activation energy Ea = -12.02 kJ/mol. The obtained hydrolysate with low impurities could be used to capture CO2 for the production of high-purity sulfur and CaCO3. Iron and other impurities in the roasted product were concentrated into the leaching slag in the form of metallic iron and akermanite. The whole process realized the recovery of zinc, and the selective and effective extraction of calcium and sulfur, which could provide an alternative process for the large-scale treatment of these hazardous wastes.


Assuntos
Óxido de Zinco , Zinco , Zinco/química , Sulfato de Cálcio/química , Cálcio , Óxido de Zinco/química , Resíduos Industriais/análise , Cinética , Hidrólise , Ferro/análise , Enxofre/química
6.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615616

RESUMO

Energetic composite materials (ECMs) are the basic materials of polymer binder explosives and composite solid propellants, which are mainly composed of explosive crystals and binders. During the manufacturing, storage and use of ECMs, the bonding surface is prone to micro/fine cracks or defects caused by external stimuli such as temperature, humidity and impact, affecting the safety and service of ECMs. Therefore, substantial efforts have been devoted to designing suitable self-healing binders aimed at repairing cracks/defects. This review describes the research progress on self-healing binders for ECMs. The structural designs of these strategies to manipulate macro-molecular and/or supramolecular polymers are discussed in detail, and then the implementation of these strategies on ECMs is discussed. However, the reasonable configuration of robust microstructures and effective dynamic exchange are still challenges. Therefore, the prospects for the development of self-healing binders for ECMs are proposed. These critical insights are emphasized to guide the research on developing novel self-healing binders for ECMs in the future.

7.
Angew Chem Int Ed Engl ; 62(2): e202211550, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36336656

RESUMO

Optimized theranostic strategies for Alzheimer's disease (AD) remain almost absent from bench to clinic. Current probes and drugs attempting to prevent ß-amyloid (Aß) fibrosis encounter failures due to the blood-brain barrier (BBB) penetration challenge and blind intervention time window. Herein, we design a near-infrared (NIR) aggregation-induced emission (AIE) probe, DNTPH, via balanced hydrophobicity-hydrophilicity strategy. DNTPH binds selectively to Aß fibrils with a high signal-to-noise ratio. In vivo imaging revealed its excellent BBB permeability and long-term tracking ability with high-performance AD diagnosis. Remarkably, DNTPH exhibits a strong inhibitory effect on Aß fibrosis and promotes fibril disassembly, thereby attenuating Aß-induced neurotoxicity. DNTPH treatment significantly reduced Aß plaques and rescued learning deficits in AD mice. Thus, DNTPH serves as the first AIE in vivo theranostic agent for real-time NIR imaging of Aß plaques and AD therapy simultaneously.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Medicina de Precisão , Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Imagem Óptica/métodos
8.
Small ; 18(25): e2201721, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35596607

RESUMO

Liquid-liquid phase separation (LLPS) drives membraneless organelles (MLOs) formation for organizing biomolecules. Artificial MLOs (AMLOs) have been constructed mostly via the LLPS of engineered proteins capable of regulating limited types of biomolecules. Here, leveraging a minimalist AMLO, driven by LLPS of polymer-oligopeptide hybrids, enrichment, recruitment, and release of multifaceted cargoes are quantitatively shown, including small fluorescent molecules, fluorophore-containing macromolecules, proteins, DNAs, and RNAs. Cargoes show up to 105 -fold enrichment, whilst recruitment and release are triggered by variations of temperature, pH, and/or ionic strength. Also, the first efficacious, rapid, and reversible control of aggregation-induced emission with over 30 folds of modulation of overall fluorescence intensity is achieved, by intensifying the aggregation of luminogens in AMLO. The AMLO is a simple yet versatile platform for potential drug delivery and biosensor applications.


Assuntos
Condensados Biomoleculares , Organelas , Organelas/química , Proteínas/química , RNA/análise
9.
J Phys Chem A ; 124(42): 8866-8873, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33045834

RESUMO

Traditionally, chemistry problems are solved by means of a deductive approach. The question to be addressed is typically related to the value of a property that is either measured experimentally, computed using quantum-chemistry software, or (more recently) predicted using a machine-learned model. In this paper, we demonstrate that an inductive approach can be adopted using End-to-End (E2E) machine learning. This approach is illustrated for tackling the following chemistry problems: (i) determine the fully coordinated (FC) and undercoordinated (UC) atoms in a molecule with one missing atom, (ii) identify the type of atom that is missing in such an incomplete molecule, and (iii) predict the direction of a reaction between two molecules according to an existing dataset. The E2E approach leads to accuracies higher than 99%, 98%, and 93% for these three problems, respectively. Finally, in order to achieve such accuracies, a descriptor for the molecules, called bag of clusters, is introduced and compared with a series previously proposed descriptors, highlighting a series of advantages.

10.
J Am Chem Soc ; 141(14): 5612-5616, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30920831

RESUMO

Although photodynamic therapy (PDT) has thrived as a promising treatment, highly active photosensitizers (PSs) and intense light power can cause treatment overdose. However, extra therapeutic response probes make the monitoring process complicated, ex situ and delayed. Now, this challenge is addressed by a self-reporting cationic PS, named TPE-4EP+, with aggregation-induced emission characteristic. The molecule undergoes mitochondria-to-nucleus translocation during apoptosis induced by PDT, thus enabling the in situ real-time monitoring via fluorescence migration. Moreover, by molecular charge engineering, we prove that the in situ translocation of TPE-4EP+ is mainly attributed to the enhanced interaction with DNA imposed by its multivalent positive charge. The ability of PS to provide PDT with real-time diagnosis help control the treatment dose that can avoid excessive phototoxicity and minimize potential side effect. Future development of new generation of PS is envisioned.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Fármacos Fotossensibilizantes/farmacologia , Células HeLa , Humanos , Imagem Molecular , Fármacos Fotossensibilizantes/química , Solubilidade
11.
J Infect Dis ; 209(12): 2000-11, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24415783

RESUMO

BACKGROUND: The mechanism underlying the ability of virulent Salmonella organisms to escape clearance by macrophages is incompletely understood. Here, we report a novel mechanism by which Salmonella escapes macrophages. METHODS: Microarray and quantitative real-time polymerase chain reaction analyses were used to screen key microRNAs regulating Salmonella-host cell interactions. Target gene was tested using luciferase reporter and Western blot assays. The role of microRNA 128 (miR-128) was assayed using intestinal epithelial cells and a mouse infection model. RESULTS: The miR-128 level in human intestinal epithelial HT29 cells was strongly increased by infection with strain SE2472, and the elevation in miR-128 levels in mouse intestine and colon tissues correlated with the level of Salmonella infection in mice. Macrophage colony-stimulating factor (M-CSF) was identified as a target of miR-128, and increased miR-128 levels in epithelial cells due to infection with strain SE2472 significantly decreased the level of cell-secreted M-CSF, leading to impaired M-CSF-mediated macrophage recruitment. The secreted proteins from Salmonella were identified as possible effectors to induce miR-128 expression via the p53 signaling pathway. Moreover, intragastric delivery of anti-miR-128 antagomir into mice significantly increased M-CSF-mediated macrophage recruitment and suppressed Salmonella infection. CONCLUSIONS: Salmonella can upregulate intestinal epithelial miR-128 expression, which, in turn, decreases levels of epithelial cell-secreted M-CSF and M-CSF-induced macrophage recruitment.


Assuntos
Intestinos/imunologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos/imunologia , MicroRNAs/metabolismo , Salmonella enteritidis/isolamento & purificação , Animais , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Feminino , Células HT29 , Humanos , Intestinos/citologia , Intestinos/microbiologia , Fator Estimulador de Colônias de Macrófagos/genética , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Infecções por Salmonella/prevenção & controle , Salmonella enteritidis/crescimento & desenvolvimento , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
12.
Oncol Lett ; 28(3): 408, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38988444

RESUMO

Procaine (PCA), a local anesthetic commonly used in stomatology, exhibits antitumor activity in some human malignancies. However, the precise mechanism underlying PCA activity remains unknown, and its antitumor effect in human tongue squamous carcinoma cells has not been reported. Flow cytometry and western blotting were used to assess the effects of PCA on mitochondrial membrane potential (ΔΨm), intracellular reactive oxygen species (ROS) production, cell cycle and apoptosis. The results suggested that PCA inhibits CAL27 and SCC-15 cell proliferation, and clone formation in a dose-dependent manner. CAL27 cells were more sensitive to PCA than SCC-15 cells. PCA also significantly inhibited cell migration, induced mitochondrial damage, reduced ΔΨm and increased intracellular ROS production. PCA causes G2/M cycle arrest and induces apoptosis. The possible mechanism for the inhibition of human tongue squamous carcinoma cell proliferation is through the regulation of ERK phosphorylation and PI3K/AKT-mediated signaling pathways. The results further suggested that autophagy occurs during PCA-induced apoptosis in CAL27 cells, and the addition of the autophagy inhibitor hydroxychloroquine sulfate further enhanced the sensitivity of PCA to inhibit cell proliferation, indicating that autophagy plays an important role in protecting cancer cells from apoptosis. PCA shows potential as an anticancer drug and its combination with autophagy inhibitors enhances its sensitivity.

13.
Adv Sci (Weinh) ; : e2405575, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39033534

RESUMO

Photothermal therapy (PTT) holds considerable clinical promise. However, insufficient PTT-induced tumor recurrence and metastasis is an urgent practical problem that needs to be solved. Herein, a biomimetic mesoporous organosilicon nano-system called PSAB is designed to precisely deplete cancer stem cells (CSCs) and prevent tumor recurrence and metastasis after PTT. The PSAB system is made up of Aggregation-induced emission (AIE)-active photothermal agent, 2TT-oC26B, and SO2 prodrug, benzothiazole sulfinate (BTS), within mesoporous organosilicon nanoparticles (MON) enclosed by an exterior platelet membrane. PSAB effectively targets CSCs both in vitro and in vivo by P-selectin/CD44 interaction. The degradation of MON and subsequent release of BTS and AIE molecules are facilitated by intracellular glutathione (GSH). Subsequently, the acidic tumor environment triggers the SO2 gas therapy from BTS. This process leads to the depletion of GSH and CSCs elimination. After combining PSAB with photothermal therapy, there is no significant tumor recurrence or metastasis. These results indicate that SO2 gas therapy and AIE-mediated PTT act synergistically to offer a unique approach for preventing tumor recurrence and metastasis after PTT, thus holding significant promise for clinical applications in cancer PTT.

14.
Biosens Bioelectron ; 253: 116086, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38422811

RESUMO

This study introduces AIEgen-Deep, an innovative classification program combining AIEgen fluorescent dyes, deep learning algorithms, and the Segment Anything Model (SAM) for accurate cancer cell identification. Our approach significantly reduces manual annotation efforts by 80%-90%. AIEgen-Deep demonstrates remarkable accuracy in recognizing cancer cell morphology, achieving a 75.9% accuracy rate across 26,693 images of eight different cell types. In binary classifications of healthy versus cancerous cells, it shows enhanced performance with an accuracy of 88.3% and a recall rate of 79.9%. The model effectively distinguishes between healthy cells (fibroblast and WBC) and various cancer cells (breast, bladder, and mesothelial), with accuracies of 89.0%, 88.6%, and 83.1%, respectively. Our method's broad applicability across different cancer types is anticipated to significantly contribute to early cancer detection and improve patient survival rates.


Assuntos
Técnicas Biossensoriais , Aprendizado Profundo , Neoplasias , Humanos , Algoritmos , Mama , Detecção Precoce de Câncer , Neoplasias/diagnóstico por imagem
15.
Mater Today Bio ; 25: 100995, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38384792

RESUMO

Controllable contraception in male animals was demonstrated through the utilization of gold nanorods' photothermal effect to accomplish mild testicular hyperthermia. However, the challenges arising from testicular administration and the non-biodegradability of nanoparticles hinder further clinical implementation. Therefore, a straightforward, non-invasive, and enhanced contraception approach is required. This study explores the utilization of human heavy chain ferritin (HFn) nanocarriers loaded with aggregation-induced emission luminogens (AIEgens) for noninvasive, controllable male contraception guided by Near-Infrared-II (NIR-II) fluorescence imaging. The HFn-caged AIEgens (HFn@BBT) are delivered via intravenous injection and activated by near-infrared irradiation. Lower hyperthermia treatment induces partial damage to the testes and seminiferous tubules, reducing fertility indices by approximately 100% on the 7th day, which gradually recovers to 80% on the 60th day. Conversely, implementation of elevated hyperthermia therapy causes total destruction of both testes and seminiferous tubules, leading to a complete loss of fertility on the 60th day. Additionally, the use of AIEgens in NIR-II imaging offers improved fluorescence efficiency and penetration depth. The findings of this study hold significant promise for the advancement of safe and effective male contraceptive methods, addressing the need for noninvasive and controllable approaches to reproductive health and population control.

16.
Bioact Mater ; 37: 299-312, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38694765

RESUMO

Ultrahigh dose-rate (FLASH) radiotherapy is an emerging technology with excellent therapeutic effects and low biological toxicity. However, tumor recurrence largely impede the effectiveness of FLASH therapy. Overcoming tumor recurrence is crucial for practical FLASH applications. Here, we prepared an agarose-based thermosensitive hydrogel containing a mild photothermal agent (TPE-BBT) and a glutaminase inhibitor (CB-839). Within nanoparticles, TPE-BBT exhibits aggregation-induced emission peaked at 900 nm, while the unrestricted molecular motions endow TPE-BBT with a mild photothermy generation ability. The balanced photothermal effect and photoluminescence are ideal for phototheranostics. Upon 660-nm laser irradiation, the temperature-rising effect softens and hydrolyzes the hydrogel to release TPE-BBT and CB-839 into the tumor site for concurrent mild photothermal therapy and chemotherapy, jointly inhibiting homologous recombination repair of DNA. The enhanced FLASH radiotherapy efficiently kills the tumor tissue without recurrence and obvious systematic toxicity. This work deciphers the unrestricted molecular motions in bright organic fluorophores as a source of photothermy, and provides novel recurrence-resistant radiotherapy without adverse side effects.

17.
Inorg Chem ; 52(7): 3620-6, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23517489

RESUMO

Four porous metalloporphyrinic framework materials, [(CH3)2NH2][Zn2(HCOO)2(Mn(III)-TCPP)]·5DMF·2H2O (1; H6TCPP = tetrakis(4-carboxyphenyl)porphyrin), [(CH3)2NH2][Cd2(HCOO)2(Mn(III)-TCPP)]·5DMF·3H2O (2), [Zn2(HCOO)(Fe(III)(H2O)-TCPP)]·3DMF·H2O (3), and [Cd3(H2O)6(µ2-O)(Fe(III)-HTCPP)2]·5DMF (4) were synthesized by heating a mixture of M(III)Cl-H4TCPP (M = Mn and Fe) and M' (M' = Zn or Cd) nitrate in a mixed solvent of DMF and acetic acid. Compounds 1-3 are built up from M'2(COO)4 paddle-wheel subunits bridged by M(III)-TCPP and formate ligands to form their 3D connections. The formate pillar heterogeneously connects with M and M' cations in 1 and 2 and homogeneously joins M' cations in 3. The µ2-O bridged Fe(III)-HTCPP dimer performs as a decadentate ligand to link 10 cadmium cations for the formation of an interesting 3D coordination network of 4. The four porphyrinic frameworks present interesting catalytic properties in the selective epoxidation of olefins, oxidation of cyclohexane, and intermolecular aldol reaction of aldehydes and ketones.

18.
Polymers (Basel) ; 15(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139898

RESUMO

Ultraviolet (UV)-curing technology as a photopolymerization technology has received widespread attention due to its advantages of high efficiency, wide adaptability, and environmental friendliness. Ultraviolet-based 3D printing technology has been widely used in the printing of thermosetting materials, but the permanent covalent cross-linked networks of thermosetting materials which are used in this method make it hard to recover the damage caused by the printing process through reprocessing, which reduces the service life of the material. Therefore, introducing dynamic bonds into UV-curable polymer materials might be a brilliant choice which can enable the material to conduct self-healing, and thus meet the needs of practical applications. The present review first introduces photosensitive resins utilizing dynamic bonds, followed by a summary of various types of dynamic bonds approaches. We also analyze the advantages/disadvantages of diverse UV-curable self-healing polymers with different polymeric structures, and outline future development trends in this field.

19.
Biomaterials ; 295: 122034, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36746049

RESUMO

Radioresistance of Cancer stem cell (CSC) is an important cause of tumor recurrence after radiotherapy (RT). Herein, we designed a type I aggregation-induced emission (AIE) photosensitiser-loaded biomimetic mesoporous organosilicon nanosystem (PMT) for precise depletion of CSC to prevent tumor recurrence after RT. This PMT system is composed of a type I AIE photosensitiser (TBP-2) loaded mesoporous organosilicon nanoparticles (MON) with an outer platelet membrane. The PMT system is able to specifically target CSC. Intracellular glutathione activity leads to MON degradation and the release of TBP-2. Type I photodynamic therapy is activated by exposure to white light, producing a large amount of hydroxyl radicals to promote CSC death. The results of in vivo experiments demonstrated specific removal of CSC following PMT treatment, with no tumor recurrence observed when combined with RT. However, tumor recurrence was observed in mice that received RT only. The expression of CSC markers was significantly reduced following PMT treatment. We demonstrate the development of a system for the precise removal of CSC with good biosafety and high potential for clinical translation. We believe the PMT nanosystem represents a novel idea in the prevention of tumor recurrence.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Camundongos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/metabolismo , Biomimética , Células-Tronco Neoplásicas/patologia , Fotoquimioterapia/métodos , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
20.
Adv Sci (Weinh) ; 10(29): e2304042, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37559173

RESUMO

Despite advances in cancer therapy, the existence of self-renewing cancer stem cells (CSC) can lead to tumor recurrence and radiation resistance, resulting in treatment failure and high mortality in patients. To address this issue, a near-infrared (NIR) laser-induced synergistic therapeutic platform has been developed by incorporating aggregation-induced emission (AIE)-active phototheranostic agents and sulfur dioxide (SO2 ) prodrug into a biocompatible hydrogel, namely TBH, to suppress malignant CSC growth. Outstanding hydroxyl radical (·OH) generation and photothermal effect of the AIE phototheranostic agent actualizes Type I photodynamic therapy (PDT) and photothermal therapy through 660 nm NIR laser irradiation. Meanwhile, a large amount of SO2 is released from the SO2 prodrug in thermo-sensitive TBH gel, which depletes upregulated glutathione in CSC and consequentially promotes ·OH generation for PDT enhancement. Thus, the resulting TBH hydrogel can diminish CSC under 660 nm laser irradiation and finally restrain tumor recurrence after radiotherapy (RT). In comparison, the tumor in the mice that were only treated with RT relapsed rapidly. These findings reveal a double-boosting ·OH generation protocol, and the synergistic combination of AIE-mediated PDT and gas therapy provides a novel strategy for inhibiting CSC growth and cancer recurrence after RT, which presents great potential for clinical treatment.


Assuntos
Recidiva Local de Neoplasia , Fotoquimioterapia , Terapia Fototérmica , Pró-Fármacos , Animais , Humanos , Camundongos , Hidrogéis , Recidiva Local de Neoplasia/terapia , Fotoquimioterapia/métodos , Óxidos de Enxofre
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