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1.
J Am Chem Soc ; 146(21): 14835-14843, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38728105

RESUMO

The transformation of carbon dioxide (CO2) into functional materials has garnered considerable worldwide interest. Metal-organic frameworks (MOFs), as a distinctive class of materials, have made great contributions to CO2 capture and conversion. However, facile conversion of CO2 to stable porous MOFs for CO2 utilization remains unexplored. Herein, we present a facile methodology of using CO2 to synthesize stable zirconium-based MOFs. Two zirconium-based MOFs CO2-Zr-DEP and CO2-Zr-DEDP with face-centered cubic topology were obtained via a sequential desilylation-carboxylation-coordination reaction. The MOFs exhibit excellent crystallinity, as verified through powder X-ray diffraction and high-resolution transmission electron microscopy analyses. They also have notable porosity with high surface area (SBET up to 3688 m2 g-1) and good CO2 adsorption capacity (up to 12.5 wt %). The resulting MOFs have abundant alkyne functional moieties, confirmed through 13C cross-polarization/magic angle spinning nuclear magnetic resonance and Fourier transform infrared spectra. Leveraging the catalytic prowess of Ag(I) in diverse CO2-involved reactions, we incorporated Ag(I) into zirconium-based MOFs, capitalizing on their interactions with carbon-carbon π-bonds of alkynes, thereby forming a heterogeneous catalyst. This catalyst demonstrates outstanding efficiency in catalyzing the conversion of CO2 and propargylic alcohols into cyclic carbonates, achieving >99% yield at room temperature and atmospheric pressure conditions. Thus, this work provides a dual CO2 utilization strategy, encompassing the synthesis of CO2-based MOFs (20-24 wt % from CO2) and their subsequent application in CO2 capture and conversion processes. This approach significantly enhances overall CO2 utilization.

2.
Cell Commun Signal ; 21(1): 18, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36691020

RESUMO

Resistin-like molecules (RELMs) are highly cysteine-rich proteins, including RELMα, RELMß, Resistin, and RELMγ. However, RELMs exhibit significant differences in structure, distribution, and function. The expression of RELMs is regulated by various signaling molecules, such as IL-4, IL-13, and their receptors. In addition, RELMs can mediate numerous signaling pathways, including HMGB1/RAGE, IL-4/IL-4Rα, PI3K/Akt/mTOR signaling pathways, and so on. RELMs proteins are involved in wide range of physiological and pathological processes, including inflammatory response, cell proliferation, glucose metabolism, barrier defense, etc., and participate in the progression of numerous diseases such as lung diseases, intestinal diseases, cardiovascular diseases, and cancers. Meanwhile, RELMs can serve as biomarkers, risk predictors, and therapeutic targets for these diseases. An in-depth understanding of the role of RELMs may provide novel targets or strategies for the treatment and prevention of related diseases. Video abstract.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular , Pneumopatias , Humanos , Resistina/fisiologia , Interleucina-4 , Fosfatidilinositol 3-Quinases
3.
Bioorg Chem ; 134: 106454, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36889199

RESUMO

Glutathione (GSH) is closely related to the occurrence and development of tumors. The intracellular GSH levels are abnormally altered when tumor cells undergo programmed cell death. Therefore, real-time monitoring of the dynamic changes of intracellular GSH levels can better enable the early diagnosis of diseases and evaluate the effects of cell death-inducing drugs. In this study, a stable and highly selective fluorescent probe AR has been designed and synthesized for the fluorescence imaging and rapid detection of GSH in vitro and in vivo, as well as patient-derived tumor tissue. More importantly, the AR probe can be used to track changes in GSH levels and fluorescence imaging during the treatment of clear cell renal cell carcinoma (ccRCC) with celastrol (CeT) via inducing ferroptosis. These findings demonstrate that the developed fluorescent probe AR exhibits high selectivity and sensitivity, as well as good biocompatibility and long-term stability, which can be used to image endogenous GSH in living tumors and cells. Also, a significant decrease in GSH levels was observed by the fluorescent probe AR during the treatment of ccRCC with CeT-induced ferroptosis in vitro and in vivo. Overall, these findings will provide a novel strategy for celastrol targeting ferroptosis in the treatment of ccRCC and the application of fluorescent probes to help reveal the underlying mechanism of CeT in the treatment of ccRCC.


Assuntos
Carcinoma de Células Renais , Carcinoma , Ferroptose , Neoplasias Renais , Humanos , Corantes Fluorescentes/farmacologia , Glutationa/metabolismo
4.
Environ Res ; 216(Pt 4): 114777, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370818

RESUMO

Facile fabrication of porous carbon materials from waste halogenated plastic is highly attractive but frequently hampered due to potential release of halogenated organic pollutants. In this study, a novel type of carbon hybrid was tentatively synthesized from a real-world halogenated plastic as an inexpensive carbon source by sub/supercritical carbon dioxide carbonization technique. It was found that halogen-free carbon carrier was advantageously synthesized through carbonization of halogenated plastic without using catalysts due to zip depolymerization, random chain cracking and free radical reactions induced by sub/supercritical carbon dioxide technique. Exhibiting with more abundant functional groups including C-O, CO groups than pyrolytic carbon carrier, the derived carbon carrier demonstrated excellent performance in selective recovery of lithium from cathode powder with highest recovery efficiency of 93.6%. Mechanism study indicated that cathode powder was transformed into low-valence states of transition metals/metal oxides and released lithium as lithium carbonate due to collapse of oxygen framework via carbothermic reduction. This work provides an applicable and green process for synthesis of alternative carbon carrier from waste halogenated plastic and its application as carbothermic reductant in lithium recovery.


Assuntos
Dióxido de Carbono , Lítio , Fontes de Energia Elétrica , Reciclagem , Plásticos , Pós
5.
Molecules ; 28(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36903585

RESUMO

The thermal analysis kinetic method was employed to solve the activation energies of the thermal decomposition reactions of urea and cyanuric acid, with the purpose of understanding the formation of deposits in the diesel engine SCR system. The deposit reaction kinetic model was established by optimizing the reaction paths and reaction kinetic parameters based on the thermal analysis test data of the key components in the deposit. The result shows that the established deposit reaction kinetic model can accurately describe the decomposition process of the key components in the deposit. Compared to the Ebrahimian model, the simulation precision of the established deposit reaction kinetic model is significantly improved above 600 K. The activation energies of the urea and cyanuric acid decomposition reactions are 84 kJ/mol and 152 kJ/mol, respectively, after model parameters identification. The identified activation energies were closest to those of the Friedman one-interval method indicating that the Friedman one-interval method is reasonable to solve the activation energies of deposit reactions.

6.
J Therm Biol ; 103: 103158, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35027194

RESUMO

Some studies revealed that steady-uniform thermal environments are not the optimal environmental state to ensure thermal comfort, and temperature ramps offer potential advantages over traditional air conditioning methods. Moreover, when exposed to the same environmental conditions, gender differences in thermal responses were often observed, but the gender differences in the ramped conditions and causal relationships remain unclear. Therefore, an experimental research was conducted in a chamber by controlling the rates and directions to study the gender differences in thermal responses to temperature ramps. Three temperature ramps conditions (A: 26 °C-24 °C-26 °C; B: 26 °C-28 °C-26 °C; C: 26 °C-30 °C-26 °C) were investigated with 60 healthy participants (30 females and 30 males) recruited. The main conclusions indicated that women are more sensitive to temperature ramp-down environments than those of their male counterparts. Direction of temperature ramps had a significant effect on human responses in cool environments but no effect was observed in warm environments. Moreover, there was no significant differences in subjective responses between genders in a 2 °C ramp-up environment from 26 °C to 28 °C. Due to psychological differences, men have a wider range of temperature acceptability than women. Furthermore, the relationships between thermal sensation and thermal comfort, thermal sensation and thermal acceptability were also established, indicating that thermal sensation had significant impacts on other psychological responses. This paper has reference value for related researchers and designers to take temperature ramps and gender differences account in the design of indoor thermal environments, which benefits to improve thermal comfort, health and energy efficiency.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Caracteres Sexuais , Temperatura Cutânea , Sensação Térmica , Adulto , Ar Condicionado , Temperatura Baixa , Planejamento Ambiental , Feminino , Calefação , Humanos , Masculino
7.
Angew Chem Int Ed Engl ; 61(26): e202201766, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35313055

RESUMO

The design and creation of soft porous crystals combining regularity and flexibility may promote potential applications for gas storage and separation due to their deformable framework's responsiveness to external stimuli. The flexibility of metal-organic frameworks (MOFs) relies on alterable degrees of freedom that are mainly provided by organic linkers or the junctions linking organic and inorganic building units. Herein, we report a new dynamic MOF whose flexibility originates from an unprecedented tailorable Mn8 O38 -cluster and shows simultaneous coordination geometry changes and ligand migration that are reversibly driven by guest exchange. This provides an extra degree of freedom to the framework's deformation, resulting in three-dimensional variations in the framework that subtly respond to varied aromatic molecules. The gas adsorption behavior of this flexible MOF was evaluated, and the selective separation of light hydrocarbons and Freon gases is achieved.

8.
Angew Chem Int Ed Engl ; 61(4): e202112097, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34779556

RESUMO

The indoor air quality is of prime importance for human daily life and health, for which the adsorbents like zeolites and silica-gels are widely used for air dehumidification and harmful gases capture. Herein, we develop a pore-nanospace post-engineering strategy to optimize the hydrophilicity, water-uptake capacity and air-purifying ability of metal-organic frameworks (MOFs) with long-term stability, offering an ideal candidate with autonomous multi-functionality of moisture control and pollutants sequestration. Through variant tuning of organic-linkers carrying hydrophobic and hydrophilic groups in the pore-nanospaces of prototypical UiO-67, a moderately hydrophilic MOF (UiO-67-4Me-NH2 -38 %) with high thermal, hydrolytic and acid-base stability is screened out, featuring S-shaped water sorption isotherms exactly located in the recommended comfortable and healthy ranges of relative humidity for indoor ventilation (45 %-65 % RH) and adverse health effects minimization (40-60 % RH). Its exceptional attributes of water-uptake working capacity/efficiency, contaminants removal, recyclability and regeneration promise a great potential in confined indoor environment application.


Assuntos
Estruturas Metalorgânicas/química , Nanopartículas/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Poluição do Ar em Ambientes Fechados , Umidade , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Água/química , Poluentes Químicos da Água/química
9.
J Cell Physiol ; 236(11): 7853-7873, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34018609

RESUMO

Epidemiological studies have shown that plasma HDL-C levels are closely related to the risk of prostate cancer, breast cancer, and other malignancies. As one of the key carriers of cholesterol regulation, high-density lipoprotein (HDL) plays an important role in tumorigenesis and cancer development through anti-inflammation, antioxidation, immune-modulation, and mediating cholesterol transportation in cancer cells and noncancer cells. In addition, the occurrence and progression of cancer are closely related to the alteration of the tumor microenvironment (TME). Cancer cells synthesize and secrete a variety of cytokines and other factors to promote the reprogramming of surrounding cells and shape the microenvironment suitable for cancer survival. By analyzing the effect of HDL on the infiltrating immune cells in the TME, as well as the relationship between HDL and tumor-associated angiogenesis, it is suggested that a moderate increase in the level of HDL in vivo with consequent improvement of the function of HDL in the TME and induction of intracellular cholesterol efflux may be a promising strategy for cancer therapy.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Mediadores da Inflamação/antagonistas & inibidores , Lipoproteínas HDL/metabolismo , Lipoproteínas HDL/uso terapêutico , Neoplasias/tratamento farmacológico , Neovascularização Patológica , Microambiente Tumoral , Animais , HDL-Colesterol/metabolismo , Humanos , Hipolipemiantes/uso terapêutico , Mediadores da Inflamação/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Recombinantes/uso terapêutico , Microambiente Tumoral/imunologia , Regulação para Cima
10.
Inorg Chem ; 60(23): 17440-17444, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34756021

RESUMO

Global warming associated with CO2 emission has led to frequent extreme weather events in recent years. Carbon capture using porous solid adsorbents is promising for addressing the greenhouse effect. Herein, we report a series of robust metal-organic cages (MOCs) featuring various functional groups, such as methyl and amine groups, for CO2/N2 separation. Significantly, the amine-group-functionalized MOC-QW-3-NH2 displays the best selective CO2 adsorption performance, as confirmed by single-component adsorption and transient breakthrough experiments. The distinct CO2 adsorption mechanism has been well studied via theoretical calculations, confirming that the amine groups play a vital role for efficiently selective CO2 adsorption resulting from hierarchical adsorbate-framework interaction.

11.
Acta Pharmacol Sin ; 42(9): 1472-1485, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33303989

RESUMO

Celastrol is a triterpene derived from the traditional Chinese medicine Tripterygium wilfordii Hook f, which displays potential anticancer activity. In the present study, we investigated the anticancer effects of celastrol against clear cell renal cell carcinoma (ccRCC) and the underlying mechanisms. Using Cancer Genome Atlas (TCGA) database and genotype-tissue expression (GTEx) database we conducted a bioinformatics analysis, which showed that the mRNA levels of liver-X receptors α (LXRα) and ATP-binding cassette transporter A1 (ABCA1) in ccRCC tissues were significantly lower than those in adjacent normal tissues. This result was confirmed by immunoblotting analysis of 4 ccRCC clinical specimens, which showed that the protein expression of LXRα and ABCA1 was downregulated. Similar results were obtained in a panel of ccRCC cell lines (786-O, A498, SN12C, and OS-RC-2). In 786-O and SN12C cells, treatment with celastrol (0.25-2.0 µM) concentration-dependently inhibited the cell proliferation, migration, and invasion as well as the epithelial-mesenchymal transition (EMT) process. Furthermore, we demonstrated that celastrol inhibited the invasion of 786-O cells through reducing lipid accumulation; celastrol concentration-dependently promoted autophagy to reduce lipid storage. Moreover, we revealed that celastrol dramatically activated LXRα signaling, and degraded lipid droplets by inducing lipophagy in 786-O cells. Finally, celastrol promoted cholesterol efflux from 786-O cells via ABCA1. In high-fat diet-promoted ccRCC cell line 786-O xenograft model, administration of celastrol (0.25, 0.5, 1.0 mg·kg-1·d-1, for 4 weeks, i.p.) dose-dependently inhibited the tumor growth with upregulated LXRα and ABCA1 protein in tumor tissue. In conclusion, this study reveals that celastrol triggers lipophagy in ccRCC by activating LXRα, promotes ABCA1-mediated cholesterol efflux, suppresses EMT progress, and ultimately inhibits cell proliferation, migration, and invasion as well as tumor growth. Thus, our study provides evidence that celastrol can be used as a lipid metabolism-based anticancer therapeutic approach.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Autofagia/efeitos dos fármacos , Carcinoma de Células Renais/metabolismo , Receptores X do Fígado/metabolismo , Triterpenos Pentacíclicos/farmacologia , Transportador 1 de Cassete de Ligação de ATP/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais/efeitos dos fármacos
12.
J Therm Biol ; 100: 103042, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34503789

RESUMO

Heat acclimation (HA) is a widely recognized physiological phenomenon of human body in hot environments. HA has many benefits, such aspreventing hyperthermia responses, and is an efficient way to improve human responses to hyperthermal environments. However, it is not known whether HA is dependent on the environmental conditions. Moreover, its mechanism and effect on the safety performance remain unexplored. In this study, we created a climate chamber to simulate a hyperthermal environment. Thirty healthy males were recruited for this study, who were then trained under the same ambient conditions (temperature of 38 °C and relative humidity (RH) of 40%). The training involved running on treadmills (at 5 km/h) to simulate heavy manual labor, and performing heat stress tests (HST) under six different conditions (32 °C/40% RH, 35 °C/40%, 38 °C/40%, 32 °C/70%, 35 °C/70%, and 38 °C/70%). Their physiological indices (rectal temperature, heart rate, sweat loss and skin temperature) and one psychological index (thermal sensation) were measured. Furthermore, a hazard avoidance test device (HATD) was designed to evaluate the individual safety performance by detecting human errors. The results show that training and environmental conditions have different effects on HA. After HA, the physiological and psychological strain were significantly improved. More importantly, HA also helped improve the participants' awareness of the dangers and required emergency responses to face potential hazards. Overall, a reasonable HA training under proper conditions is helpful to ensure the safety of human beings. More research is needed to study the role of HA on safety performance.


Assuntos
Reação de Fuga , Resposta ao Choque Térmico , Condicionamento Físico Humano/métodos , Adulto , Temperatura Corporal , Teste de Esforço/instrumentação , Teste de Esforço/métodos , Frequência Cardíaca , Humanos , Masculino , Condicionamento Físico Humano/instrumentação , Tempo de Reação , Segurança , Sensação Térmica
13.
Cell Commun Signal ; 18(1): 119, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746850

RESUMO

Exosomes have been considered as novel and potent vehicles of intercellular communication, instead of "cell dust". Exosomes are consistent with anucleate cells, and organelles with lipid bilayer consisting of the proteins and abundant lipid, enhancing their "rigidity" and "flexibility". Neighboring cells or distant cells are capable of exchanging genetic or metabolic information via exosomes binding to recipient cell and releasing bioactive molecules, such as lipids, proteins, and nucleic acids. Of note, exosomes exert the remarkable effects on lipid metabolism, including the synthesis, transportation and degradation of the lipid. The disorder of lipid metabolism mediated by exosomes leads to the occurrence and progression of diseases, such as atherosclerosis, cancer, non-alcoholic fatty liver disease (NAFLD), obesity and Alzheimer's diseases and so on. More importantly, lipid metabolism can also affect the production and secretion of exosomes, as well as interactions with the recipient cells. Therefore, exosomes may be applied as effective targets for diagnosis and treatment of diseases. Video abstract.


Assuntos
Exossomos/metabolismo , Metabolismo dos Lipídeos , Animais , Humanos , Lipídeos/biossíntese , Modelos Biológicos
14.
Inorg Chem ; 59(20): 14856-14860, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-32986428

RESUMO

A flexible-robust copper(II) metal-organic framework, denoted as LIFM-100, has been successfully synthesized using a fluorinated linear dicarboxylate to link copper ions. LIFM-100 exhibits a breathing effect, which can transform reversibly between a large form (lp) and a narrow form (np) from single crystal to single crystal. In addition, LIFM-100 shows good thermal and chemical stability. By the introduction of trifluoromethyl functional groups and uncoordinated carboxyl acids, LIFM-100 features a good CO2/R22 adsorption/separation performance at 298 K, showing potential in natural gas purification and CO2/R22 capture.

15.
J Cell Physiol ; 234(12): 21436-21449, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31054175

RESUMO

Obesity is well-known as the second factor for tumorigenesis after smoking and is bound up with the malignant progression of several kinds of cancers, including esophageal cancer, liver cancer, colorectal cancer, kidney cancer, and ovarian cancer. The increased morbidity and mortality of obesity-related cancer are mostly attributed to dysfunctional adipose tissue. The possible mechanisms connecting dysfunctional adipose tissue to high cancer risk mainly focus on chronic inflammation, obesity-related microenvironment, adipokine secretion disorder, and browning of adipose tissue, and so forth. The stromal vascular cells in adipose tissue trigger chronic inflammation through secreting inflammatory factors and promote cancer cell proliferation. Hypertrophic adipose tissues lead to metabolic disorders of adipocytes, such as abnormal levels of adipokines that mediate cancer progression and metastasis. Cancer patients often show adipose tissue browning and cancerous cachexia in an advanced stage, which lead to unsatisfied chemotherapy effect and poor prognosis. However, increasing evidence has shown that adipose tissue may display quite opposite effects in cancer development. Therefore, the interaction between cancers and adipose tissue exert a vital role in mediates adipose tissue dysfunction and further leads to cancer progression. In conclusion, targeting the dysfunction of adipose tissue provides a promising strategy for cancer prevention and therapy.


Assuntos
Tecido Adiposo/patologia , Carcinogênese/patologia , Neoplasias/patologia , Animais , Progressão da Doença , Humanos , Inflamação/patologia
16.
J Am Chem Soc ; 141(6): 2589-2593, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30645112

RESUMO

We demonstrate herein a facile strategy to engineer versatile catalytically active coordination interspace in the same primitive metal-organic framework (MOF) for variable heterogeneous catalysis. Different functional ligands can be reversibly inserted into and removed from proto-LIFM-28 individually or successively to bring in single or binary catalytic sites for specific reactions and switch the parent MOF to multipurpose catalysts. Alcohol-oxidation, Knoevenagel-condensation, click, acetal, and Baylis-Hillman reactions are achievable through simple exchange of a single catalytic spacer, while sequential or stepwise reactions are designable via selective combination of two catalytic spacers with different functionalities, thus making proto-LIFM-28 a multivariate MOF for multiuse and economic catalysis.

17.
Inorg Chem ; 58(1): 61-64, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30588809

RESUMO

A trifluoromethyl functionalized linker and Cu-O chain composed MOF, LIFM-100, was used as "crystalline sponge" to determine eight hardly crystallized liquids' configurations based on its flexibility conformation, suitable pore size, electron-rich channel environment, and low symmetric space group. The H bond interactions between host-guest and guest-guest were well analyzed.

18.
Angew Chem Int Ed Engl ; 58(47): 17033-17040, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31507037

RESUMO

We transformed the hydrophilic metal-organic framework (MOF) UiO-67 into hydrophobic UiO-67-Rs (R=alkyl) by introducing alkyl chains into organic linkers, which not only protected hydrophilic Zr6 O8 clusters to make the MOF interspace superoleophilic, but also led to a rough crystal surface beneficial for superhydrophobicity. The UiO-67-Rs displayed high acid, base, and water stability, and long alkyl chains offered better hydrophobicity. Good hydrophobicity/oleophilicity were also possible with mixed-ligand MOFs containing metal-binding ligands. Thus, a (super)hydrophobic MOF catalyst loaded with Pd centers efficiently catalyzed Sonogashira reactions in water at ambient temperature. Studies of the hydrophobic effects of the coordination interspace and the outer surface suggest a simple de novo strategy for the synthesis of superhydrophobic MOFs that combine surface roughness and low surface energy. Such MOFs have potential for environmentally friendly catalysis and water purification.

19.
Angew Chem Int Ed Engl ; 58(40): 14379-14385, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31355964

RESUMO

In multiphoton excited fluorescence (MPEF), high-energy upconversion emission is obtained from low-energy excitation by absorbance of two or more photons simultaneously. In a pressure-induced fluorochromic process, the emission energy is switched by outer pressure stimuli. Now, five metal-organic frameworks containing the same ligand with simultaneous multiphoton absorption and pressure-induced fluorochromic attributes were studied. One-, two-, and three-photon excited fluorescence (1/2/3PEF) can be achieved in the frameworks, which exhibit pressure-induced blue-to-yellow fluorochromism. The performances are closely dependent with the topologies, flexibilities, and packing states of the frameworks and chromophores therein. The multiphoton upconversion performance can be intensified by pressure-related structural contraction. Over ten-fold increment in the 2PA active cross-section up to 2217 GM is achieved in pressed LIFM-114 compared with the 210 GM for pristine sample at 780 nm.

20.
BMC Cancer ; 18(1): 967, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30305062

RESUMO

BACKGROUND: Conventional chemotherapy is commonly used to treat non-small cell lung cancer (NSCLC) however it increases therapeutic resistance. In contrast, metronomic chemotherapy (MET) is based on frequent drug administration at lower doses, resulting in inhibition of neovascularization and induction of tumor dormancy. This study aims to evaluate the inhibitory effects, adverse events, and potential mechanisms of MET Vinorelbine (NVB) combined with an angiogenesis inhibitor (Endostar). METHODS: Circulating endothelial progenitor cells (CEPs), apoptosis rate, expression of CD31, vascular endothelial growth factor (VEGF), hypoxia inducible factor-1 (HIF-1α) were determined using flow cytometry, western blot analysis, immunofluorescence staining and Enzyme-linked immunosorbent assay (ELISA) analysis. And some animals were also observed using micro fluorine-18-deoxyglucose PET/computed tomography (18F-FDG PET/CT) to identify changes by comparing SUVmax values. In addition, white blood cell (WBC) counts and H&E-stained sections of liver, lungs, kidney, and heart were performed in order to monitor toxicity assessments. RESULTS: We found that treatment with MET NVB + Endo was most effective in inhibiting tumor growth, decreasing expression of CD31, VEGF, HIF-1α, and CEPs, and reducing side effects, inducing apoptosis, such as expression of Bcl-2, Bax and caspase-3. Administration with a maximum tolerated dose of NVB combined with Endostar (MTD NVB + Endo) demonstrated similar anti-tumor effects, including changes in glucose metabolism with micro fluorine-18-deoxyglucose PET/computed tomography (18F-FDG PET/CT) imaging, however angiogenesis was not inhibited. Compared with either agent alone, the combination of drugs resulted in better anti-tumor effects. CONCLUSION: These results indicated that MET NVB combined with Endo significantly enhanced anti-tumor and anti-angiogenic responses without overt toxicity in a xenograft model of human lung cancer.


Assuntos
Administração Metronômica , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Endostatinas , Neoplasias Pulmonares/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Vinorelbina , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Lewis , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Linhagem Celular Tumoral , Endostatinas/administração & dosagem , Endostatinas/efeitos adversos , Humanos , Neoplasias Pulmonares/irrigação sanguínea , Camundongos , Vinorelbina/administração & dosagem , Vinorelbina/efeitos adversos , Ensaios Antitumorais Modelo de Xenoenxerto
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