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1.
Carbohydr Polym ; 222: 115039, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320053

RESUMO

The purpose of this study was to design an injectable hydrogel with temperature-sensitive property for safe and high efficient in vivo colon cancer hyperthermia and chemotherapy. Chitosan (CS) solution was injected into the tumor at room temperature and automatically gelled after warming to body temperature in the present of ß-glycerophosphate (ß-GP). Combined localized tumor photothermal and chemotherapy were achieved by dissolving photothermal material MoS2/Bi2S3-PEG (MBP) nanosheets and drug molecule doxorubicin (DOX) into the hydrogel, and the gel system could encapsulate DOX and MBP nanosheets and prevent them from entering the blood circulation and damaging normal tissues and cells. More importantly, the CS/MBP/DOX (CMD) hydrogel exhibited a photothermal efficiency of 22.18% and 31.42% in the first and second near infrared light (NIR I and NIR II) biowindows respectively at a low MBP concentration (0.5 mg/mL). Besides, the release of the DOX from CMD hydrogel was controllable since the gel temperature could be governed by NIR laser irradiation. Moreover, the chitosan-based hydrogel had antibacterial effects. The designed composite hydrogel is anticipated to act as a platform for the high efficient treatment of tumors owing to the different penetration depths of NIR I and NIR II.

2.
Int J Nanomedicine ; 14: 3893-3909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239663

RESUMO

Background: Photothermal and chemotherapy treatment has been frequently studied for cancer therapy; however, chemotherapy is equally toxic to both normal and cancer cells. The clinical application value of most kinds of photothermal transforming agents remains limited, due to their poor degradation and minimal accumulation in tumors. Materials and methods: We reported the synthesis of photothermal transforming agents (MoS2) and chemotherapeutic (doxorubicin, DOX) co-loaded electrospun nanofibers using blend electrospinning for the treatment of postoperative tumor recurrence. Results: Under the irradiation of an 808 nm laser, the as-prepared chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an admirable photothermal conversion capability with a photothermal conversion efficiency of 23.2%. These composite nanofibers are in vitro and in vivo biocompatible. In addition, they could control the sustained release of DOX and the generated heat can sensitize the chemotherapeutic efficacy of DOX via enhancing its release rate. Their chemo-/photothermal combined therapy efficiency was systematically studied in vitro and in vivo. Instead of circulating with the body fluid, MoS2 was trapped by the nanofibrous matrix in the tumor and so its tumor-killing ability was not compromised, thus rendering this composite nanofiber a promising alternative for future clinical translation within biomedical application fields. Conclusion: Chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an excellent photothermal conversion capability with a photothermal conversion efficiency of 23.2% and can completely inhibit the postoperative tumor reoccurrence.


Assuntos
Dissulfetos/química , Doxorrubicina/uso terapêutico , Molibdênio/química , Nanofibras/química , Nanotecnologia/métodos , Neoplasias/terapia , Fototerapia , Animais , Materiais Biocompatíveis/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Células HT29 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanofibras/ultraestrutura , Recidiva Local de Neoplasia/patologia , Neoplasias/sangue , Neoplasias/patologia , Neoplasias/cirurgia , Padrões de Referência , Resultado do Tratamento
3.
Phys Chem Chem Phys ; 21(27): 14516-14520, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31069357

RESUMO

d-Limonene, obtained from the rind of citrus fruits, was demonstrated as a green solvent to realize air-stable and highly efficient triplet-triplet annihilation photon upconversion (TTA-UC). This natural low-toxic compound also contributed to noncoherent UC excited by a solar simulator in air, making TTA-UC materials promising candidates in solar energy and other practical applications. The rapid deoxygenating ability of d-limonene was thoroughly investigated. This system demonstrated very good UC performance for a fluid solution under ambient conditions. Besides, other eight types of terpene were also explored to enrich the alternatives for air-stable TTA-UC in protic and aprotic fluidic environments. This work provides a terpene-based protective platform for oxygen-sensitive TTA-UC applications ranging from life science to photonic devices.

4.
Colloids Surf B Biointerfaces ; 177: 346-355, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30772669

RESUMO

With an excellent near-infrared (NIR) light-responsive property, polypyrrole (PPy) nanoparticle has emerged as a promising NIR photothermal transducing agent for tumor photothermal therapy (PTT). Herein, we reported the PVP mediated one-pot synthesis of colloidal stable and biocompatible PPy nanoparticles (PPy-PVP NPs) for combined tumor photothermal-chemotherapy. The influence of molecular weight and PVP concentration on the spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency of the resultant PPy-PVP NPs was systematically studied. By choosing PVP with a molecular weight of 360 kDa (concentration of 5 mg/mL) as the template and surface modifier during the synthesis, PPy-PVP NPs with optimal spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency were synthesized. Findings in this study are anticipated to provide an in-depth understanding of the important character of surface engineering in the rational design and biomedical applications of PPy NPs.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Nanopartículas/química , Fototerapia , Polímeros/farmacologia , Pirróis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Coloides/química , Coloides/farmacologia , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Raios Infravermelhos , Camundongos , Camundongos Endogâmicos , Tamanho da Partícula , Polímeros/síntese química , Polímeros/química , Pirróis/síntese química , Pirróis/química , Propriedades de Superfície , Células Tumorais Cultivadas
5.
Org Lett ; 21(1): 261-265, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30582704

RESUMO

A general oxyalkylation of terminal alkynes enabled by iron catalysis has been developed. Primary and secondary alkyl iodides acted as the alkylating reagents and afforded a range of α-alkylated ketones under mild reaction conditions. Acetyl tert-butyl peroxide (TBPA) was used as the radical relay precursor, providing the initiated methyl radical to start the radical relay process. Preliminary mechanistic studies were conducted, and late-stage functionalizations of natural product derivatives were performed.

6.
J Am Chem Soc ; 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30509065

RESUMO

Many reactions involving allenyl ion species have been studied but reactions involving allenyl radicals are less well understood, perhaps because of the inconvenience associated with the generation of short-lived allenyl radicals. We describe here a versatile method for the generation of allenyl radicals and their previously unreported applications in the intermolecular 1,4-carbocyanation and 1,4-sulfimidocyanation of 1,3-enynes. With the assistance of the trifunctional reagents, alkyl diacyl peroxides or N-fluorobenzenesulfonimide, a range of synthetically challenging multi-substituted allenes can be prepared with high regioselectivity. These multisubstituted allenes can be easily transformed into synthetically useful structures such as fluorinated vinyl cyanides, lactones, functionalized allenyl amides, 1-aminonaphthalenes and pyridin-2(1H)-ones, and several novel transformations are reported. The results of radical scavenger and radical clock experiments are consistent with the proposed allenyl radical pathway. Density functional theory (DFT) and IR spectroscopy studies suggest the formation of an isocyanocopper(II) species in the ligand exchange step. Based on the results of IR, DFT and diastereoselectivity studies, an isocyanocopper(II)/copper(I) catalytic cycle is proposed, which differs from the previously considered Cu(III) mechanism in cyanation reactions.

7.
Artigo em Inglês | MEDLINE | ID: mdl-30430823

RESUMO

Alginate-Ca2+ hydrogel has been used to immobilize photothermal materials as well as chemotherapy drugs at lesion sites to prevent their entry into the bloodstream. However, the alginate-Ca2+ gelation mechanism may result in hardening of the blood vessels due to Ca2+ migration to the lesion site. In this study, a unique and facile one-pot formation of chemotherapeutic (doxorubicin, DOX) and polypyrrole (PPy)-containing alginate hydrogel was designed by introducing Fe3+, which can synchronously induce the polymerization of pyrrole and gelatinization of alginate, into the DOX/pyrrole/alginate solution. The formed composite hydrogel was endowed with superior photothermal conversion properties in both the NIR-I (650-950 nm) and NIR-II (1000-1700 nm) biowindows and light-to-heat conversion efficiency higher than 50%, which enabled effective tumor hyperthermia treatment. Besides, NIR irradiation could be used as a remote controller to trigger the DOX-release due to the heat generation, thus achieving continuous and on-demand tumor chemotherapy. The composite polymer hydrogels exhibited favorable hemo-, cyto-, and histocompatibility, as well as simple and cost-effective preparation and good clinical prospects.

8.
J Sci Food Agric ; 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30338529

RESUMO

BACKGROUND: Polysaccharides, common components of natural products extensively studied as dietary supplements and functional foods, have been found to have various activities. In the present study, a water-soluble polysaccharide, namely GBSP3a, was isolated and purified from G. biloba sarcotesta. Then the anti-inflammatory activity of GBSP3a in LPS-induced RAW264.7 macrophages and the potential underlying molecular mechanisms were assessed. RESULTS: GBSP3a exerted its anti-inflammatory effect by remarkably inhibiting the secretion of pro-inflammatory mediators and cytokines including nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), and interleukin- 1 beta (IL-1ß) in LPS-stimulated RAW264.7 macrophages. Excessive mRNA and protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were dose-dependently inhibited by GBSP3a in LPS-stimulated RAW264.7 cells. Further research suggested that the anti-inflammatory effect of GBSP3a can be attributed to the modulation of the NF-κB and MAPK signaling pathways. CONCLUSION: GBSP3a exhibits anti-inflammatory activity and it exerts its anti- inflammatory effect likely through suppressing both NF-κB and MAPK signaling pathway, indicating that GBSP3a could be used for the development of anti-inflammatory agent or nutraceuticals. This article is protected by copyright. All rights reserved.

9.
Macromol Biosci ; 18(10): e1800206, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30188003

RESUMO

In this work, a novel kind of electrospun microfiber to deliver a photothermal agent and an anticancer drug to tumor sites is explored. Photothermal therapy agent (MoS2 nanosheets) and doxorubicin (DOX) are incorporated with poly(lactic-co-glycolic acid) (PLGA) microfiber via electrospinning a solution of PLGA, MoS2 , and DOX. The designed microfiber with uniform fibrous morphology and negligible in vitro/in vivo hemo-/histo-toxicity is used as a durable photothermal agent, which shows an excellent photothermal transform ability and acceptable photothermal stability in both the first and second near-infrared light (NIR I and II) biowindows. The synergistic in vivo tumor chemotherapy and photothermal therapy efficiency of the composite microfibers are studied in postoperative treatment of cancer. It is found that the tumor postoperative reoccurrence can be completely prohibited owing to the synergistic tumor therapy efficiency in both the NIR I and NIR II biowindows.

10.
Org Lett ; 20(11): 3202-3205, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29786445

RESUMO

This paper reports a new method for the generation of substituted 1,3-enynes, whose synthesis by other methods could be a challenge. The dehydrative decarboxylative cascade coupling reaction of propargyl alcohol with alkyl peroxides is enabled by an iron catalyst and alkylating reagents. Primary, secondary, and tertiary alkyl groups can be introduced into 1,3-enynes, affording various substituted 1,3-enynes in moderate to good yields. Mechanistic studies suggest the involvement of a radical-polar crossover pathway.

11.
Chem Asian J ; 13(17): 2522-2528, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-29767475

RESUMO

A variety of alkyl peresters and alkyl diacyl peroxides, which are readily accessible from carboxylic acids, are utilized as general primary, secondary, and tertiary alkylating reagents for iron-catalyzed vinylic C-H alkylation of vinyl arenes, dienes, and 1,3-enynes. This transformation affords olefinic products in up to 98 % yield with high E/Z values. A broad range of functionalities, including carboxyl, boronic acid, methoxy, ester, amino, and halides, are tolerated. This protocol provides a facile approach to some olefins that are difficult to access, and hence, offers an alternative to existing systems. The synthetic utility of this method is demonstrated by late-stage functionalization of selected natural-product derivatives.

12.
Neurol Res ; 40(6): 459-465, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29589518

RESUMO

OBJECTIVE: The purpose of this study was to compare the efficacy of repetitive transcranial magnetic stimulation (rTMS) applied at different frequencies to the contra-lesional hemisphere to optimize the treatment of post-stroke non-fluent aphasia. METHOD: Patients with post-stroke non-fluent aphasia were divided randomly into four groups: a high-frequency rTMS (HF-rTMS) group (10 Hz), a low-frequency rTMS (LF-rTMS) group (1 Hz), a sham stimulation group, and a control group. All groups received the standard treatment (consisting of drug therapy, conventional physical exercises, and speech training); in the HF-rTMS and LF-rTMS, this was supplemented with magnetic stimulation that targeted the mirror area within the right hemispheric Broca's area. Patients' language ability was assessed prior to, immediately after, and at 2 months post-treatment by the Chinese version of the Western Aphasia Battery (WAB). RESULTS: When measured immediately post-treatment, as well as at 2 months post-treatment, the LF-rTMS group exhibited a more marked improvement than the HF-rTMS group in spontaneous speech, auditory comprehension, and aphasia quotients (AQ). Compared to the control group, the HF-rTMS cohort exhibited significant improvement at 2-months post-treatment in repetition and AQ. CONCLUSIONS: LF-rTMS and HF-rTMS are both beneficial to the recovery of linguistic function in patients with post-stroke non-fluent aphasia. LF-rTMS produced immediate benefits that persisted long-term, while HF-rTMS only produced long-term benefits. In addition, the benefits produced with LF-rTMS were more marked than those produced by HF-rTMS.


Assuntos
Afasia/etiologia , Afasia/reabilitação , Acidente Vascular Cerebral/complicações , Estimulação Magnética Transcraniana/métodos , Afasia/fisiopatologia , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fonoterapia , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral , Resultado do Tratamento
13.
ACS Appl Mater Interfaces ; 10(4): 3392-3404, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29313334

RESUMO

The objective of the present study was to construct an alginate (AG)-based phase-changeable and injectable hydrogel for imaging-guided tumor hyperthermia and chemotherapy. Based on the binding between the α-l-guluronic blocks of AG and calcium ions, the AG/MoS2/Bi2S3-poly(ethylene glycol) (MBP)/doxorubicin (DOX) solution formed a cross-linked hydrogel to simultaneously encapsulate MBP nanosheets and DOX within the hydrogel matrix. The in situ formed hydrogel can act as a reservoir to control the release of entrapped drug molecules, and the doped MBP nanosheets and DOX can realize computed tomography/photoacoustic dual-modal imaging-guided in vivo tumor photothermal therapy and chemotherapy, respectively. The AG/MBP/DOX hydrogel exhibited excellent photothermal conversion properties with mass extinction coefficient of 45.1 L/g/cm and photothermal conversion efficiency of 42.7%. Besides, the heat from the photothermal transformation of MBP can promote drug diffusion from the hydrogel to realize on-demand drug release. Additionally, the hydrogel system can restrain MBP and DOX from entering into the blood stream during therapy, and therefore substantially decrease their side effects on normal organs. More importantly, the drug loading of the AG hydrogel was general and can be extended to the encapsulation of antibiotics, such as amoxicillin, for the prevention of postoperative infections.

14.
Org Lett ; 19(22): 6120-6123, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29090941

RESUMO

An environmentally benign, copper-catalyzed diazidation of a broad range of olefins, including vinylarenes, unactivated alkenes, allene, and dienes, under mild conditions with TMSN3 (trimethylazidosilane) as azido source, has been developed. This reaction can be carried out in organic solvent or in aqueous solution where water is the sole solvent. The functional group compatibility of this reaction is good, which is proved by late-stage functionalizations of complex substrates.

15.
Chemistry ; 23(43): 10254-10258, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28627009

RESUMO

An iron-catalyzed oxyalkylation of alkynes with alkyl peroxides as the alkylating reagents has been investigated. Alkyl peroxides are readily available from aliphatic acids and serve simultaneously as the alkylating reagents and internal oxidants. Primary, secondary, and tertiary alkyl groups of aliphatic acids were readily incorporated into C-C triple bonds and diverse α-alkylated ketones were synthesized. Mechanism studies revealed that this reaction involves highly reactive alkyl free radicals. A unique equilibrium between lauric acid and water catalyzed by the iron(III) catalyst was observed.


Assuntos
Alquinos/química , Ácidos Carboxílicos/química , Ferro/química , Peróxidos/química , Alquilação , Catálise , Descarboxilação , Radicais Livres/química , Cetonas/química , Estrutura Molecular , Relação Estrutura-Atividade , Água
16.
J Environ Sci (China) ; 56: 153-163, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28571851

RESUMO

A submerged internal circulating membrane coagulation reactor (MCR) was used to treat surface water to produce drinking water. Polyaluminum chloride (PACl) was used as coagulant, and a hydrophilic polyvinylidene fluoride (PVDF) submerged hollow fiber microfiltration membrane was employed. The influences of trans-membrane pressure (TMP), zeta potential (ZP) of the suspended particles in raw water, and KMnO4 dosing on water flux and the removal of turbidity and organic matter were systematically investigated. Continuous bench-scale experiments showed that the permeate quality of the MCR satisfied the requirement for a centralized water supply, according to the Standards for Drinking Water Quality of China (GB 5749-2006), as evaluated by turbidity (<1 NTU) and total organic carbon (TOC) (<5mg/L) measurements. Besides water flux, the removal of turbidity, TOC and dissolved organic carbon (DOC) in the raw water also increased with increasing TMP in the range of 0.01-0.05MPa. High ZP induced by PACl, such as 5-9mV, led to an increase in the number of fine and total particles in the MCR, and consequently caused serious membrane fouling and high permeate turbidity. However, the removal of TOC and DOC increased with increasing ZP. A slightly positive ZP, such as 1-2mV, corresponding to charge neutralization coagulation, was favorable for membrane fouling control. Moreover, dosing with KMnO4 could further improve the removal of turbidity and DOC, thereby mitigating membrane fouling. The results are helpful for the application of the MCR in producing drinking water and also beneficial to the research and application of other coagulation and membrane separation hybrid processes.


Assuntos
Água Potável/química , Compostos de Manganês/química , Óxidos/química , Purificação da Água/métodos , China , Filtração , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Oxirredução , Polivinil , Qualidade da Água
17.
Angew Chem Int Ed Engl ; 55(24): 6911-4, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27144957

RESUMO

A critical requirement for the successful recognition of multiple analytes is the acquisition of abundant sensing information. However, for this to be achieved requires massive chemical sensors or multiplex materials, which complicates the multianalysis. Thus, there is a need to develop a strategy for the facile and efficient recognition of multiple analytes. Herein, we explore the angle-dependent structural colors of photonic crystals to provide abundant optical information, thereby generating a rainbow-color chip to realize the convenient recognition of multiple analytes. By simply using a multiangle analysis method, the monophotonic crystal matrix chip can differentially enhance fluorescence signals over broad spectral ranges, thereby resulting in abundant sensing information for highly efficient multiple analysis. Twelve saccharides with similar structures, as well as saccharides in different concentrations and mixtures, were successfully discriminated.

18.
Phys Chem Chem Phys ; 18(10): 7537, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26883830

RESUMO

Correction for 'Photon upconversion: from two-photon absorption (TPA) to triplet-triplet annihilation (TTA)' by Changqing Ye et al., Phys. Chem. Chem. Phys., 2016, DOI: .

19.
Phys Chem Chem Phys ; 18(16): 10818-35, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-26843136

RESUMO

Organic upconversion is a unique process in which low-energy light (usually NIR light) is converted to high-energy light through either the two-photon absorption (TPA) mechanism or the triplet-triplet annihilation (TTA) mechanism. Both TPA upconversion (TPA-UC) and TTA upconversion (TTA-UC) have been actively investigated in recent years due to their intriguing applications in optics, biophotonics, and solar energy utilization. Although they show some similarity (i.e., belonging to the nonlinear two-quantum process and needing focused excitation light), TPA-UC and TTA-UC are very different, such as in mechanism, characteristics involved, molecular design and potential applications. Here, we collectively reviewed these two kinds of upconversion processes and compared their respective characteristics and merits. We also present recent advances made in the areas of TPA- and TTA-UC, the remaining challenges and opportunities, with particular emphasis on molecular engineering of these two active upconversion materials.

20.
Org Lett ; 18(3): 392-5, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26790009

RESUMO

Copper catalyzed 1,2-alkylesterification of 1,3-dienes with diacyl peroxides affords branched allylic esters in excellent regioselectivity, including products with a newly generated fully substituted carbon center. The only byproduct is CO2. The reaction proceeds by a radical mechanism as suggested by spin trap and crossover experiments.

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