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1.
Biosensors (Basel) ; 13(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37232869

RESUMO

Rapid and accurate detection of changes in glucose (Glu) and hydrogen peroxide (H2O2) concentrations is essential for the predictive diagnosis of diseases. Electrochemical biosensors exhibiting high sensitivity, reliable selectivity, and rapid response provide an advantageous and promising solution. A porous two-dimensional conductive metal-organic framework (cMOF), Ni-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene), was prepared by using a one-pot method. Subsequently, it was employed to construct enzyme-free paper-based electrochemical sensors by applying mass-producing screen-printing and inkjet-printing techniques. These sensors effectively determined Glu and H2O2 concentrations, achieving low limits of detection of 1.30 µM and 2.13 µM, and high sensitivities of 5573.21 µA µM-1 cm-2 and 179.85 µA µM-1 cm-2, respectively. More importantly, the Ni-HHTP-based electrochemical sensors showed an ability to analyze real biological samples by successfully distinguishing human serum from artificial sweat samples. This work provides a new perspective for the use of cMOFs in the field of enzyme-free electrochemical sensing, highlighting their potential for future applications in the design and development of new multifunctional and high-performance flexible electronic sensors.


Assuntos
Glucose , Peróxido de Hidrogênio , Humanos , Porosidade , Catálise , Técnicas Eletroquímicas/métodos
2.
Front Nutr ; 9: 868166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634364

RESUMO

Background: Osteoporosis is the most common metabolic bone disease. Recent studies have shown that malnutrition can promote the development of osteoporosis. However, the incidence of malnutrition in patients with osteoporosis and the relationship between malnutrition and all-cause mortality has not been adequately studied. Therefore, our study investigated the relationship between malnutrition and all-cause mortality in patients with osteoporosis. Methods: We analyzed data on 7,700 adults ≥20 years of age during National Health and Nutrition Examination Survey (NHANES) 2005-2010. Each patient was assigned to one of three groups: normal nutritional status, mild malnutrition, and moderate to severe malnutrition. Survival curves and univariate and multivariable cox regressions based on the NHANES recommended weights were used to assess the association between malnutrition status and mortality. Moreover, cox proportional hazards regression analyses were performed on the matched pairs. Results: Overall, 7,700 eligible individuals with osteoporosis were included in the final analysis, and the mean age was 52.0 ± 0.4 years. From the Kaplan-Meier curves for long-term all-cause mortality of malnutrition, worsening malnutrition status was associated with higher incidence of all-cause mortality. In the fully adjusted models, the adjusted hazard ratio (aHR) was 1.54 [95% confidence interval (CI), 1.02-2.31, p = 0.039] at mild malnutrition status and 2.70 (95%CI, 1.95-3.74, p < 0.001) at moderate to severe malnutrition status. The cox model after matching indicated that malnutrition was still a high mortality risk than no malnutrition (aHR = 2.23, 95% CI, 1.66-3.01, p < 0.001). Conclusions: Poor malnutrition status, common in osteoporotic patients, is strongly associated with a risk for all-cause mortality comparable to that seen with normal nutritional status. These findings highlight the importance of risk stratification for nutritional status in osteoporotic patients and the implementation of strategies that is now available to help prevent malnutrition in these patients.

3.
Biosens Bioelectron ; 210: 114328, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35512583

RESUMO

Optical flexible biosensors are novel sensors fabricated on flexible or ductile materials that are used for the detection of analytes. Compared to traditional sensors, these biosensors offer greater flexibility, which allows them to adapt to different working environments, to meet the deformation requirements of humans. Flexible devices can not only detect alterations in analytes in vitro, but can also realize real-time and non-invasive monitoring of the variation of physical conditions or metabolites in vivo. Flexible devices are earning increasing attention from researchers and clinicians. In the present review, we summarize and introduce the detection principles, key analytes, and applications of optical flexible biosensors in the diagnosis/treatment of diseases as well as health detection. Moreover, the remaining challenges of flexible devices and their perspectives have also been addressed. We hope that this review will pave ways for the development of more feasible and multifunctional flexible devices.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Humanos
4.
RSC Med Chem ; 13(2): 117-128, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35308022

RESUMO

l-Asparaginase (l-ASNase is the abbreviation, l-asparagine aminohydrolase, E.C.3.5.1.1) is an enzyme that is clinically employed as an antitumor agent for the treatment of acute lymphoblastic leukemia (ALL). Although l-ASNase is known to deplete l-asparagine (l-Asn), causing cytotoxicity in leukemia cells, the specific molecular signaling pathways are not well defined. Because of the deficiencies in the production and administration of current formulations, the l-ASNase agent in clinical use is still associated with serious side effects, so controlling its dose and activity monitoring during therapy is crucial for improving the treatment success rate. Accordingly, it is urgent to summarize and develop effective analytical methods to detect l-ASNase activity in treatment. However, current reports on these detection methods are fragmented and also have not been systematically summarized and classified, thereby not only delaying the investigations of specific molecular mechanisms, but also hindering the development of novel detection methods. Herein, in this review, we provided a detailed summary of the l-ASNase structures, antitumor mechanism and side effects, and current detection approaches, such as fluorescence assays, colorimetric assays, spectroscopic assays and some other assays. All of them possess unique advantages and disadvantages, so it has been difficult to establish clear criteria for clinical application. We hope that this review will be of some value in promoting the development of l-ASNase activity detection methods.

5.
Front Nutr ; 9: 993061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687731

RESUMO

Background: Patients with Rheumatoid arthritis (RA) are prone to malnutrition. However, it is rare studies assessing the relationship between malnutrition and all-cause mortality in patients with RA. Objective: To investigate the relationship between malnutrition and all-cause mortality in patients with RA in a large national sample cohort. Methods: We analyzed data on 1,976 adults ≥ 18 years of age during National Health and Nutrition Examination Survey (NHANES) 1999-2014. We chose the Controlled Nutritional Status Score (CONUT) and the Nutritional Risk Index (NRI) to assess the nutritional status of patients with RA. The Kaplan-Meier (KM) survival curves Cox proportional hazards regression models were used to analyze the associations between malnutrition and all-cause mortality. Results: Of the 1,976 patients with RA (57.38 ± 0.40 years, female 59.9%, non-Hispanic white 69.9%), the prevalence of malnutrition was 18.8% by used the CONUT and 26.6% by used the NRI. The KM survival curves showed that malnutrition was associated with a higher incidence of all-cause mortality during the 10-year follow-up period (log-rank test, P < 0.001). In the fully corrected model, the adjusting hazard ratio (aHR) for all-cause mortality in patients with moderate to severe malnutrition with CONUT and NRI were 5.63 (95% CI, 2.55-12.45; P < 0.001) and 2.56 (95% CI, 1.81-3.62; P < 0.001), respectively, compared with patients without malnutrition. Conclusion: Malnutrition is very prevalent in patients with RA, approximately 18.8% (CONUT) to 26.6% (NRI). Malnutrition is strongly associated with an increased risk of all-cause mortality. These findings underscore the importance of attention and intervention in the nutritional status of patients with RA. Further clinical trials are needed to prospectively assess the effect of nutritional interventions on the prognosis of patients with RA.

6.
Research (Wash D C) ; 2021: 9757126, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778790

RESUMO

Sweat contains a broad range of critical biomarkers including ions, small molecules, and macromolecules that may indirectly or directly reflect the health status of the human body and thereby help track disease progression. Wearable sweat biosensors enable the collection and analysis of sweat in situ, achieving real-time, continuous, and noninvasive monitoring of human biochemical parameters at the molecular level. This review summarizes the physiological/pathological information of sweat and wearable sweat biosensors. First, the production of sweat pertaining to various electrolytes, metabolites, and proteins is described. Then, the compositions of the wearable sweat biosensors are summarized, and the design of each subsystem is introduced in detail. The latest applications of wearable sweat biosensors for outdoor, hospital, and family monitoring are highlighted. Finally, the review provides a summary and an outlook on the future developments and challenges of wearable sweat biosensors with the aim of advancing the field of wearable sweat monitoring technology.

7.
J Mater Chem B ; 9(38): 7909-7926, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34611678

RESUMO

Photothermal therapy (PTT) has been widely applied in cancer therapy as a result of its non-invasive, localized treatment and good therapeutic effect. In general, the final therapeutic effect of PTT mainly depends on the photothermal materials, which can be further considered to be determined by the photothermal conversion efficiency, biocompatibility, and photothermal stability of photothermal materials. In this review, photothermal materials including inorganic materials, organic materials, and organic-inorganic composite materials in recent years have been summarized in terms of the mechanism, preparation, and cancer therapy applications. In the end, the perspectives and obstacles in their further development are overviewed.


Assuntos
Raios Infravermelhos , Neoplasias/terapia , Terapia Fototérmica/métodos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Humanos , Compostos Inorgânicos/química , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Neoplasias/tratamento farmacológico , Compostos Orgânicos/química
8.
ACS Appl Mater Interfaces ; 12(29): 32432-32445, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32573194

RESUMO

To maximize the utilization and response to the high oxidative stress environment of tumor sites while avoiding the dilemma of enhancing reactive oxygen species (ROS) response in a single way, mitochondrial targeting combined with fluorescent self-reporting polymeric nanocarriers (1K-TPP and 2K-TPP) with grafted structures were synthesized via a chemoenzymatic method in a high yield to simultaneously enhance the drug delivery of endogenous ROS responses. 1K-TPP and 2K-TPP loaded doxorubicin (DOX) at a high content over 12% and formed homogeneous spherical micelles. In vitro, both of them showed promising high sensitivity (detection limit below 200 nM H2O2), fast response, and ratiometric fluorescent self-reporting properties (fluorescent enhancement more than 200 times) to ROS and excellent stability under physiological conditions, while achieving a rapid release of the DOX in response to 1 mM H2O2. Cell co-localization experiments exhibited that they had favorable mitochondrial targeting, and mitochondrial isolation experiments also confirmed that the TPP-modified 1K-TPP selectively accumulated nearly three times in mitochondria than that in total cells. The internalization of 1K-TPP and 2K-TPP into cancer cells was greatly improved by nearly 200% compared to that of unmodified control (1K-OH and 2K-OH) and also explored a unique energy-dependent endocytosis. Furthermore, stimulation of endogenous ROS enhanced the green fluorescence intensity (up to 51.4%) of the linked probe so as to destroy the internal structure of the nanocarriers, achieving self-reporting of the drug's intracellular release and tracking of the intracellular location of nanocarriers. The cytotoxicity of DOX-loaded 1K-TPP and 2K-TPP in tumor cells with a higher ROS content showed statistical superiority to that of 1K-OH and 2K-OH, benefiting from the extremely good endogenous ROS response sensitivity leading to the differential selective release of drugs. These results demonstrate the potential of 1K-TPP and 2K-TPP, especially for 1K-TPP, as mitochondria-targeted, fluorescent self-reporting nanocarriers for combined enhancement of endogenous ROS responsiveness.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Fluorescência , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Antibióticos Antineoplásicos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Mitocôndrias/metabolismo , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Polímeros/síntese química , Polímeros/química , Propriedades de Superfície
9.
Molecules ; 25(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041136

RESUMO

A series of new hyperbranched aliphatic poly(ß-thioether ester)s were prepared by the enzymatic ring-opening polycondensation of 1,4-oxathiepan-7-one (OTO) and AB2/ABB' comonomer with acid-labile ß-thiopropionate groups. Two kinds of comonomers, methyl 3-((3-hydroxy-2-(hydroxymethyl)propyl)thio)propanoate (HHTP) and methyl 3-((2,3-dihydroxypropyl)thio)propanoate (DHTP), with different primary alcohols and secondary alcohols, were synthesized by thiol-ene click chemistry and thiol-ene Michael addition, respectively. Immobilized lipase B from Candida antarctica (CALB), Novozym 435, was used as the catalyst. The random copolymers were characterized by 1H-NMR, 13C-NMR, GPC, TGA, and DSC. All branched copolyesters had high molecular weights over 15,000 Da with narrow polydispersities in the range of 1.75-2.01 and were amorphous polymers. Their degradation properties under acidic conditions were also studied in vitro. The polymeric nanoparticles of hyperbranched poly(ß-thioether ester)s were successfully obtained and showed good oxidation-responsive properties, indicating their potential for biomedical applications.


Assuntos
Lipase/química , Poliésteres/química , Polímeros/química , Álcoois/química , Materiais Biocompatíveis/química , Candida/enzimologia , Catálise , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Nanopartículas/química , Oxirredução , Fenantrenos/química
10.
Mater Sci Eng C Mater Biol Appl ; 108: 110358, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923953

RESUMO

In the field of drug delivery, the controlled release of drugs is continuously one of the highly prioritized research domains. Stimuli-responsive polymers are being investigated as drug delivery vehicles that modulate pharmaceutical effect via tumor specific mechanisms. In this work, a biocompatible graft copolymer (denoted as PSNC-g-mPEG/TPE) was constructed, which comprised a triple-responsive polycarbonate backbone coupled with fluorescent TPE and hydrophilic methoxypoly(ethylene glycol) (mPEG) segments. This multifunctional amphiphilic copolymer was able to self-assemble in aqueous solutions and acted as a drug delivery vehicle that releases cargo in response to multiple biological stimuli (ROS, pH and enzymes). And the results of confocal laser scanning microscopy (CLSM) suggested that these micelles could be rapidly internalized by cells and achieve more effective drug release in cancer cells. Furthermore, the cytotoxicity assays proved the safety of this material. It is anticipated that this strategy has enormous potential in constructing novel anticancer therapeutics.


Assuntos
Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Corantes Fluorescentes/síntese química , Polímeros/química , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Endocitose , Corantes Fluorescentes/química , Humanos , Camundongos , Micelas , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Espectrometria de Fluorescência , Estilbenos/síntese química , Estilbenos/química , Suínos
11.
Crit Rev Food Sci Nutr ; 60(13): 2294-2302, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31272187

RESUMO

Umami taste is the most recent confirmed basic taste in addition to sour, sweet, bitter, and salty. It has been controversial because of its effects on human nutritional benefit. Based on the available literatures, this review categorized 13 positive and negative effects of umami taste on human health. On the positive side, umami taste can improve food flavor and consumption, improve nutrition intake of the elderly and patients, protect against duodenal cancer, reduce ingestion of sodium chloride, decrease consumption of fat, and improve oral functions. On the other hand, umami taste can also induce hepatotoxicity, cause asthma, induce migraine headaches, damage the nervous system, and promote obesity. Due to its novelty, there are many functions and effects of umami taste waiting to be discovered. With further investigation, more information regarding the effects of umami taste on human health will be discerned.


Assuntos
Dieta , Saúde , Paladar/fisiologia , Dieta/efeitos adversos , Humanos , Estado Nutricional/efeitos dos fármacos , Paladar/efeitos dos fármacos
12.
Food Chem ; 303: 125407, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466032

RESUMO

Theaflavin (TF), which is the key pigment in black tea, is a health-promoting food component with beneficial effects on humans. However, the interactions by which these effects are transferred and exerted into protein-rich foods are unclear. Here, egg ovalbumin (OVA) was selected as a representative dietary protein to ascertain their binding mechanism. Steady-state, time-resolved fluorescence and isothermal titration calorimetric results showed that TF can interact well with OVA with an affinity magnitude of 104. The noncovalent binding was mainly driven by hydrophobic interaction and hydrogen bonds. Structural analysis displayed that the TF binding pocket significantly overlapped with one of the surrounding specific IgE-binding epitopes, thereby causing a subtle structural adjustment on the secondary conformation of OVA. The biological complexation model that was delineated here will help understand how black tea dyes egg white in tea egg products and for the development of protein-rich carriers in functional foods.


Assuntos
Biflavonoides/química , Camellia sinensis/química , Catequina/química , Clara de Ovo/química , Ovalbumina/química , Pigmentos Biológicos/química , Extratos Vegetais/química , Animais , Galinhas , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligação Proteica , Chá/química
13.
Biomater Sci ; 7(8): 3277-3286, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31180396

RESUMO

Dual stimuli-responsive camptothecin polymeric prodrugs (CPT Prodrugs) with grafted structures were designed via chemoenzymatic methods and combined with doxorubicin (DOX) for synergistic drug delivery to improve anticancer efficiency. The CPT Prodrugs loaded DOX with a high efficiency through the cooperative contribution of several interaction forces. The produced amphiphilic polymeric prodrugs loaded with DOX, referred to as DOX@CPT Prodrugs, formed homogeneous spherical micelles of appropriate sizes (sub-50 nm). The DOX@CPT Prodrug micelles showed excellent stability in release experiments under in vitro physiological conditions and maintained over 80% drug loading after 4 weeks when stored at 4 °C. Under weakly acidic pH and reduced glutathione (GSH) conditions, the DOX@CPT Prodrugs with high disulfide and tertiary amine content achieved synergistic release of the two loaded drugs and biodegraded into low-molecular-weight compounds. The cell experiments confirmed that the internalization of DOX@CPT Prodrugs into cancer cells was greatly improved by nearly 30% compared with that of free drugs. Furthermore, the synergistic drug delivery system exhibited superior anticancer efficiency with highly improved cell selectivity ratios (up to 127.0%) and greatly enhanced synergistic effects (up to 23.9%) benefiting from good long-term stability, better internalization by cells and sensitive pH and GSH dual-responsivity. In addition, the DOX@CPT Prodrugs with suitable sizes and good water solubility also exhibited a greater penetrability in the case of simulating solid tumors than the free drugs. These results demonstrate the potential of DOX@CPT Prodrugs as biodegradable, dual-responsive combination therapy nanocarriers for synergistic anticancer treatment.


Assuntos
Camptotecina/química , Camptotecina/metabolismo , Doxorrubicina/farmacologia , Glutationa/metabolismo , Polímeros/química , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Liberação Controlada de Fármacos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Micelas , Permeabilidade
14.
J Mater Chem B ; 6(43): 6993-7003, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-32254582

RESUMO

A series of amphiphilic graft copolymers, poly(N-propargyldiethanolamine 4,4'-dithiodibutyionate)-graft-monomethoxy poly(ethylene glycol) (PPD-g-mPEG), were designed via a chemoenzymatic method for pH and reduced glutathione (GSH) dual-responsive drug delivery. The effects of percent grafting and molecular weights of mPEG on critical micelle concentration (CMC) values, size of micelles, drug loading and dual-response were tested. The graft copolymers could easily form homogeneous spherical micelles with appropriate sizes and zeta-potentials. The micelles of PPD-g-mPEG copolymers loaded doxorubicin (DOX) in high efficiency, and showed excellent stability under physiological conditions and synergetic dual-response to weakly acidic pH and GSH. In vitro experiments confirmed that the DOX-loaded micelles could be internalized into cancer cells efficiently and release DOX over time. Furthermore, cell cytotoxicity assays indicated that the graft copolymers were non-cytotoxic to both cancerous and normal cells while the DOX-loaded micelles greatly improved the selectivity ratios between HeLa cells and HL-7702 cells. DOX-loaded micelles also avoided hemolysis of red blood cells (RBCs) effectively compared with commercialized doxorubicin hydrochloride. All these demonstrated the potential of PPD-g-mPEG as a model to create more functional dual-responsive nanocarriers for controlled drug delivery.

15.
Acta Biomater ; 58: 136-145, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28611004

RESUMO

An injectable, phospholipid-based phase transition gel (PPTG) has been developed for prolonging the release of ropivacaine (RO) for local anesthesia. PPTG was prepared by mixing phospholipids, medium-chain triglyceride and ethanol. Prior to injection, the PPTG is in a sol state with low viscosity. After subcutaneous injection, the PPTG rapidly forms a gel in situ, which acts as a drug release depot as verified by in vitro release profiles and in vivo pharmacokinetics. Administering RO-PPTG to rats led to a significantly smaller initial burst release than administering RO solution or RO base suspension. Nerve blockade in guinea pigs lasted 3-fold longer after injection of RO-PPTG than after injection of RO solution. RO-PPTG showed good biocompatibility and excellent degradability in vivo. These results suggest that this PPTG-based depot system may be useful for sustained release of local anesthetics to prolong analgesia without causing systemic toxicity. STATEMENT OF SIGNIFICANCE: The sustained release of local anesthetics at the surgical site after a single injection is the optimal method to control post-surgical pain. In situ forming implant is an attractive alternative for the sustained release of local anesthetics. However, its practical use is highly limited by certain drawbacks including high viscosity, involved toxic organic solvents and fast drug release. To date, phospholipids-based phase transition gel (PPTG) is emerging for clinical development because of the non-toxicity, biocompatibility and ready availability of phospholipids in body. Thus, we present a novel strategy for sustained release of local anesthetics to control post-surgical pain based on PPTG, which showed a prolonged duration of nerve blockade and excellent biocompatibility.


Assuntos
Amidas , Fosfolipídeos , Triglicerídeos , Amidas/química , Amidas/farmacocinética , Amidas/farmacologia , Animais , Linhagem Celular , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Etanol/química , Etanol/farmacocinética , Etanol/farmacologia , Géis , Cobaias , Camundongos , Bloqueio Nervoso/métodos , Transição de Fase , Fosfolipídeos/química , Fosfolipídeos/farmacocinética , Fosfolipídeos/farmacologia , Ratos , Ropivacaina , Triglicerídeos/química , Triglicerídeos/farmacocinética , Triglicerídeos/farmacologia
16.
Biomater Sci ; 5(4): 718-729, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28197596

RESUMO

Cationic liposomes and polymers are both important candidates for use as non-viral gene vectors. However, both of them have special shortcomings and application limits. This work is devoted to the combination of advantages of liposomes and polymers. The ring-opening polymerization strategy was used for the preparation of amphiphilic polymers from cyclen-based cationic small lipids. The non-hydrophobic polymer and the corresponding lipids were also prepared for performing structure-activity relationship studies. Gel electrophoresis results reveal that both the lipopolymers and liposomes could effectively condense DNA into nanoparticles and protect DNA from degradation. Compared to polymers, the DNA binding ability of liposomes is more affected by hydrophobic tails. Under the same dosage, the synthetic polymers have stronger DNA binding ability than the liposomes. In vitro transfection experiments show that the polymers could give better transfection efficiency, which was much higher than those of the corresponding liposomes and non-hydrophobic polymer. The oleyl moiety is suitable for lipidic vectors, but things were different for polymers. Under optimized conditions, up to 14.2 times higher transfection efficiency than that for 25 kDa bPEI could be obtained. More importantly, the lipopolymers showed much better serum tolerance, which was further confirmed by protein adsorption, gel electrophoresis, flow cytometry, and CLSM assays. The results indicate that ring-opening polymerization is a promising strategy for the enhancement of the gene delivery efficiency and biocompatibility of cationic lipids.


Assuntos
DNA/administração & dosagem , Técnicas de Transferência de Genes , Plasmídeos/administração & dosagem , Polímeros/química , Tensoativos/química , Cátions/química , Ciclamos , DNA/genética , Células HEK293 , Células HeLa , Células Hep G2 , Compostos Heterocíclicos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Lipossomos/química , Plasmídeos/genética , Polimerização , Transfecção/métodos
17.
ACS Appl Mater Interfaces ; 6(18): 15733-42, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25177769

RESUMO

In order to improve the transfection efficiency (TE) and biocompatibility, we synthesized a series of hyperbranched cationic polymers by ring-opening polymerization between diepoxide and several polyamines. These materials can condense plasmid DNA efficiently into nanoparticles that have much lower cytotoxicity than those derived from bPEI. In vitro transfection experiments showed that polymers prepared from branched or cyclic polyamine (P1 and P5) exhibited TE several times higher than 25KDa bPEI. More significantly, serum seemed to have no negative effect on P1-P5 mediated transfection. On the contrary, the TE of P1 improved, even when the serum concentration reached 70%. Several assays demonstrated the excellent serum tolerance of such polycationic vectors: bovine serum albumin (BSA) adsorption assay revealed considerably lower protein adsorption of P1-P5 than PEI; P1 showed better DNA protection ability from degradation by DNase I than PEI; flow cytometry results suggested that any concentration of serum may not decrease the cellular uptake of P1/DNA polyplex; and confocal laser scanning microscopy also found that serum has little effect on the transfection. By using specific cellular uptake inhibitors, we found that the polyplexes enter the cells mainly via caveolae and microtubule-mediated pathways. We believe that this ring-opening polymerization may be an effective synthetic approach toward gene delivery materials with high biological activity.


Assuntos
Materiais Biocompatíveis/química , Vetores Genéticos/química , Poliaminas/química , Transfecção/métodos , Animais , Materiais Biocompatíveis/farmacocinética , Materiais Biocompatíveis/toxicidade , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Vetores Genéticos/farmacocinética , Vetores Genéticos/toxicidade , Células HEK293 , Células HeLa , Humanos , Poliaminas/farmacocinética , Poliaminas/toxicidade , Polieletrólitos , Polimerização , Soroalbumina Bovina
18.
Eur J Med Chem ; 78: 118-25, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24681389

RESUMO

Routine clinical implementation of human gene therapy requires safe and efficient gene delivery methods. Linear biodegradable polyesters with carbon-carbon double bonds are prepared from unsaturated diacids and diols. Subsequent appending of low molecular weight PEI by Michael addition gives target cationic polymers efficiently. Agarose gel retardation and fluorescence quenching assays show that these materials have good DNA binding ability and can completely retard plasmid DNA at weight ratio of 0.8. The formed polyplexes have appropriate sizes around 275 nm and zeta-potential values about +20-35 mV. The cytotoxicities of these polymers assayed by MTT are much lower than that of 25 kDa PEI. In vitro transfection toward 7402, HEK293 and U-2OS cells show that polymer P1 may give dramatically higher transfection efficiency (TE) than 25 kDa PEI, especially in U-2OS cells, suggesting that such polymer might be promising non-viral gene vectors.


Assuntos
Técnicas de Transferência de Genes , Vetores Genéticos/química , Poliésteres/química , Polietilenoimina/química , Linhagem Celular , Sobrevivência Celular , Vetores Genéticos/metabolismo , Células HEK293 , Humanos , Microscopia de Fluorescência , Peso Molecular , Poliésteres/metabolismo , Polietilenoimina/metabolismo
19.
Soft Matter ; 10(8): 1199-213, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24652240

RESUMO

A series of novel aliphatic polyesters with azido functional groups were synthesized via the direct lipase-catalyzed polycondensation of dialkyl diester, diol and 2-azido-1,3-propanediol (azido glycerol) using immobilized lipase B from Candida antarctica (CALB). The effects of polymerization conditions including reaction time, temperature, enzyme amount, substrates and monomer feed ratio on the molecular weights of the products were studied. The polyesters with pendant azido groups were characterized by (1)H NMR, (13)C NMR, 2D NMR, FTIR, GPC and DSC. Alkyne end-functionalized poly(ethylene glycol) containing a cleavable acetal group was then grafted onto the polyester backbone by copper-catalyzed azide-alkyne cycloaddition (CuAAC, click chemistry). Using fluorescence spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM), these amphiphilic graft copolymers were found to readily self-assemble into nanosized micelles in aqueous solution with critical micelle concentrations between 0.70 and 1.97 mg L(-1), and micelle sizes from 20-70 nm. The degradation of these polymers under acidic conditions was investigated by GPC and (1)H NMR spectroscopy. Cell cytotoxicity tests indicated that the micelles had no apparent cytotoxicity to Bel-7402 cells, suggesting their potential as carriers for controlled drug delivery.


Assuntos
Azidas/química , Proteínas Fúngicas/química , Lipase/química , Poliésteres/síntese química , Propilenoglicóis/química , Biocatálise , Candida albicans/enzimologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Poliésteres/farmacologia , Polimerização , Tensoativos/química
20.
Appl Biochem Biotechnol ; 172(6): 3128-40, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24497044

RESUMO

An inexpensive, facile, and environmentally benign method was developed to improve the activity and stability of Candida rugosa lipase (triacylglycerol acylhydrolase) immobilized on microemulsion-based organogels (CRL MBGs) via the addition of additives during immobilization. The additives used were polyethylene glycol (PEG) or polysaccharides. This study is the first report on the effect of additives in CRL MBGs. Among the tested additives, PEG produced the most improvement in the immobilized CRL, enhancing its stability in organic solvents (specifically polar solvents). The results of circular dichroism and fluorescence spectra experiments indicated that exposure of the acidic CRL to electronegative additives in the buffer, such as polyethylenimine and the electropositive surfactant cetyltrimethylammonium bromide, may change the lipase secondary structure, ultimately causing enzyme inactivation. However, sodium bis(2-ethylhexyl)sulfosuccinate and PEG 2000 had minimal effects on the secondary structure of CRL. The CRL MBGs containing PEG 2000 demonstrated remarkable retention of their catalytic activity during the recycling test. No significant changes in enzymatic activity were observed, even after nine runs, and 90% of the original yield was maintained after 15 cycles.


Assuntos
Candida/química , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Lipase/química , Polietilenoglicóis/química , Polissacarídeos/química , Candida/enzimologia , Cetrimônio , Compostos de Cetrimônio/química , Ácido Dioctil Sulfossuccínico/química , Emulsões , Estabilidade Enzimática , Reutilização de Equipamento , Géis , Polietilenoimina/química , Estrutura Secundária de Proteína , Eletricidade Estática
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