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1.
J Nanobiotechnology ; 22(1): 129, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528554

RESUMO

The development of nanomaterials for delivering natural compounds has emerged as a promising approach for atherosclerosis therapy. However, premature drug release remains a challenge. Here, we present a ROS-responsive biomimetic nanocomplex co-loaded with Geniposide (GP) and Emodin (EM) in nanoliposome particles (LP NPs) for targeted atherosclerosis therapy. The nanocomplex, hybridized with the macrophage membrane (Møm), effectively evades immune system clearance and targets atherosclerotic plaques. A modified thioketal (TK) system responds to ROS-rich plaque regions, triggering controlled drug release. In vitro, the nanocomplex inhibits endothelial cell apoptosis and macrophage lipid accumulation, restores endothelial cell function, and promotes cholesterol effluxion. In vivo, it targets ROS-rich atherosclerotic plaques, reducing plaque area ROS levels and restoring endothelial cell function, consequently promoting cholesterol outflow. Our study demonstrates that ROS-responsive biomimetic nanocomplexes co-delivering GP and EM exert a synergistic effect against endothelial cell apoptosis and lipid deposition in macrophages, offering a promising dual-cell therapy modality for atherosclerosis regression.


Assuntos
Aterosclerose , Emodina , Iridoides , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/tratamento farmacológico , Lipossomos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Emodina/farmacologia , Emodina/uso terapêutico , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Colesterol
2.
J Nanobiotechnology ; 21(1): 158, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208681

RESUMO

PCSK9, which is closely related to atherosclerosis, is significantly expressed in vascular smooth muscle cells (VSMCs). Moreover, Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) mediated phenotypic transformation, abnormal proliferation, and migration of VSMCs play key roles in accelerating atherosclerosis. In this study, by utilizing the significant advantages of nano-materials, a biomimetic nanoliposome loading with Evolocumab (Evol), a PCSK9 inhibitor, was designed to alleviate atherosclerosis. In vitro results showed that (Lipo + M)@E NPs up-regulated the levels of α-SMA and Vimentin, while inhibiting the expression of OPN, which finally result in the inhibition of the phenotypic transition, excessive proliferation, and migration of VSMCs. In addition, the long circulation, excellent targeting, and accumulation performance of (Lipo + M)@E NPs significantly decreased the expression of PCSK9 in serum and VSMCs within the plaque of ApoE-/- mice.


Assuntos
Aterosclerose , Pró-Proteína Convertase 9 , Camundongos , Animais , Pró-Proteína Convertase 9/metabolismo , Lipossomos , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo
3.
Zhongguo Zhong Yao Za Zhi ; 47(13): 3475-3480, 2022 Jul.
Artigo em Zh | MEDLINE | ID: mdl-35850798

RESUMO

The present study prepared shell-core nanoparticles comprising poly(lactic-co-glycolic acid)(PLGA) cores encapsulated by shells composed of mixed lipids(Lipoid S100 and DSPE-PEG 2000) or polymer F127 to investigate the effects of shell composition on overcoming physiological barriers of gastrointestinal mucus and intestinal epithelial cells and improving bioavailability.The results are expected to provide references for the research on the improvement of the oral bioavailability of Chinese medicine by nanocar-riers. Silibinin(SLB) was used as a model drug to prepare PLGA nanoparticles coated with the shell of mixed lipids(SLB-LPNs) or F127(SLB-FPNs) via a modified nanoprecipitation method.Transmission electron microscopy showed that both LPNs and FPNs were spherical with a core-shell structure.The average particle sizes of SLB-LPNs and SLB-FPNs were(94.13±2.23) and(95.42±4.91) nm, respectively.The Zeta potential values were(-39.3±2.8) and(-17.0±0.2) mV, respectively.X-ray diffraction analysis revealed the presence of SLB in the two types of nanoparticles in a molecular or amorphous state.The ability of nanoparticles to cross both the mucus and epithelial barriers were evaluated using the cellular internalization kinetics assay.LPNs showed a higher rate of cell internalization than FPNs, indicating that LPNs could penetrate the mucus layer and become internalized by cells more rapidly.As revealed by the in vivo pharmacokinetic assay in rats with SLB suspension as the reference, the relative oral bioavailability of SLB-LPNs and SLB-FPNs was 400.37% and 923.31%, respectively.The effect of SLB-FPNs in improving oral bioavailability was more significant than that of SLB-LPNs.In summary, shell composition can influence the ability of nanoparticles to overcome oral physiological bar-riers, such as the mucus layer and intestinal epithelial cells, and improve oral bioavailability.Shell-core structured nanoparticles are promising nanocarriers for oral drug delivery systems.


Assuntos
Nanopartículas , Animais , Disponibilidade Biológica , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Muco , Nanopartículas/química , Tamanho da Partícula , Polímeros , Ratos
4.
Anal Chem ; 92(1): 1611-1617, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31834786

RESUMO

Self-assembled polydiacetylene (PDA) vesicles, with the distinct advantages of low-cost materials, simple preparation, and excellent chromatic properties, can be perfectly combined with a colorimetric strip for on-site inspection. Herein, without involving expensive reagents and instruments, a visual colorimetric strip based on well-prepared PDA vesicles was developed to analyze and monitor histamine in deep-sea fish and its canned food. The standard calorimetric card for semiquantitative detection of histamine was successfully prepared and the quantitative detection can be further realized by analyzing the gray value using ImageJ and "Color Grab" in a smart phone. After optimizing the assembly conditions, this assay exhibited a linear response to histamine within the range from 70 to 2240 ppm. With excellent stability and sensitivity, this strip can be used to monitor the quality change of canned fish at different temperatures, so that people can avoid suffering from histamine poisoning, suggesting that it holds great potential in the intelligent system for on-site detection and real-time monitoring.


Assuntos
Colorimetria , Histamina/análise , Polímero Poliacetilênico/química , Animais , Técnicas Biossensoriais , Peixes , Tamanho da Partícula , Polímero Poliacetilênico/síntese química , Propriedades de Superfície , Fatores de Tempo
5.
J Am Chem Soc ; 140(47): 16001-16005, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30376327

RESUMO

Value-added utilization of lignin waste streams is vital to fully sustainable and economically viable biorefineries. However, deriving substantial value from its main constituents is seriously hindered by the constant requirement for expensive coenzymes. Herein, we devised a coenzyme-free biocatalyst that could transform lignin-derived aromatics into various attractive pharmaceutical and polymer building blocks. At the center of our strategy is the integrated use of new mining phenolic acid decarboxylase and aromatic dioxygenase with extremely high catalytic efficiency, which realizes the value-added utilization of lignin in a coenzyme-independent manner. Notably, a new temperature/pH-directed strategy was proposed to eliminate the highly redundant activities of endogenous alcohol dehydrogenases. The major components of lignin were simultaneously converted to vanillin and 4-vinylphenol. Since the versatile biocatalyst could efficiently convert many other renewable lignin-related aromatics to valuable chemicals, this green route paves the way for enhancing the entire efficiency of biorefineries.


Assuntos
Derivados de Benzeno/química , Carboxiliases/química , Oxigenases de Função Mista/química , Ascomicetos/enzimologia , Bacillus coagulans/enzimologia , Benzaldeídos/síntese química , Biocatálise , Cinamatos/química , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Lignina/química , Estirenos/síntese química , Temperatura
6.
Anal Chem ; 90(2): 1388-1394, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29243476

RESUMO

Abuse of antibiotics results in a large number of antibiotics residues in the environment and even causes the problem of "super bacteria". Therefore, it is crucial to develop a powerful analytic method to monitor antibiotics quickly and simply. Photonic crystal (PC), as a sensing material, has promising application prospects. Herein, we try to use PC to realize pretreatment-free and label-free detection of Ciprofloxacin (CF) through Michael addition reaction. The recognition process is carried out by the Michael addition reaction between the piperazine group of CF and the o-benzoquinone group on the PC. The monodisperse microspheres with o-benzoquinone groups are prepared by polymerization and oxidation and then stacked to form PC. During the detection, the peak intensity of the PC decreases with the increasing CF concentration, and the linear range is from 2 to 512 µg/L. The limit of detection (LOD) is 0.76 µg/L. Furthermore, the PC retains 97% of the initial response after storage in a Petri dish at room temperature for 1 month, which shows that it has good stability. Moreover, CF in fish farming water can be detected directly without any pretreatment and label, and the results are in good accordance with the LC-MS-MS results. This Michael-addition-mediated PC is accurate, easily prepared, cost-efficient, and long-term stable. In addition, it is environmentally friendly, because little organic solvent is needed during both the preparation and the detection.


Assuntos
Antibacterianos/análise , Ciprofloxacina/análise , Dopamina/análogos & derivados , Tecnologia de Fibra Óptica/instrumentação , Polimetil Metacrilato/química , Poluentes Químicos da Água/análise , Cristalização , Desenho de Equipamento , Pesqueiros , Limite de Detecção , Oxirredução , Fótons , Polimerização
7.
Small ; 14(14): e1703574, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29484803

RESUMO

Micro- and nanotopographies can interfere with bacteria attachment, however, the interplay existing between surface chemistry and topography remains unclear. Here, self-assembled spherical micrometer- silica and nanometer poly(methyl methacrylate) (PMMA)-sized particles are used to make binary colloidal crystal (BCC) topographical patterns to study bacterial attachment. A uniform surface chemistry of allylamine plasma polymer (AAMpp) is coated on the top of the BCCs to study only the topography effects. The uncoated and coated BCCs are exposed to Pseudomonas aeruginosa, and the surfaces and bacteria are characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and fluorescence microscopy. It is found that bacteria attachment to the uncoated BCCs is delayed and individual cells are attracted to the small particle regions of the patterns. Surprisingly, this phenomenon is also observed for the AAMpp-coated BCCs, with bacteria attaching to the small particle regions of the pattern, in stark contrast to uniform flat films of AAMpp that are highly adhesive toward P. aeruginosa. Also, the overall levels of bacterial attachment are significantly reduced by the BCC patterns compared to controls. Thus, there is a trade-off that exists between chemistry and topography that can be exploited to delay the onset of P. aeruginosa biofilm formation on surfaces.


Assuntos
Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Aderência Bacteriana/fisiologia , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Espectroscopia Fotoeletrônica , Polimetil Metacrilato/química , Propriedades de Superfície
8.
Nanomedicine ; 14(7): 2215-2226, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29964220

RESUMO

Inflammation and oxidative stress are two major factors that are involved in the pathogenesis of atherosclerosis. A smart drug delivery system that responds to the oxidative microenvironment of atherosclerotic plaques was constructed in the present study. Andrographolide-loaded micelle was assembled from the block copolymer of poly(ethylene glycol) and poly(propylene sulphide) (PEG-PPS) for the purpose of simultaneously decreasing inflammatory response and the level of reactive oxygen species (ROS) to treat atherosclerosis. Owing to the ROS-responsive nature of PEG-PPS, the micelle not only serves as a stimuli-responsive drug carrier to quickly release the encapsulated drug, andrographolide, but also consumes ROS by itself at the pathologic sites, upon which the expressions of pro-inflammatory cytokines are effectively suppressed and oxidative stress is alleviated. Consequently, the andrographolide-loaded micelle demonstrated remarkable therapeutic effects both in vitro and in vivo. In conclusion, the andrographolide-loaded PEG-PPS micelle can synchronically alleviate inflammation and oxidative stress, providing a promising and innovative strategy against atherosclerosis.


Assuntos
Aterosclerose/tratamento farmacológico , Diterpenos/farmacologia , Sistemas de Liberação de Medicamentos , Inflamação/tratamento farmacológico , Placa Aterosclerótica/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Animais , Aorta/patologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Diterpenos/administração & dosagem , Diterpenos/química , Portadores de Fármacos/química , Feminino , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos Knockout para ApoE , Micelas , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Polietilenoglicóis/química , Polímeros/administração & dosagem , Polímeros/química
9.
Adv Exp Med Biol ; 1078: 271-290, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30357628

RESUMO

Polymer-based nanoparticles (PNPs) are attractive in part due to their ultra-small size, versatility and target specificity. Therefore, PNPs have been increasingly used in a variety of biomedical applications including diagnoses and therapeutic treatment. In this chapter, we focus on the recent studies (within 5 years) with some new ideas/agent's application in biomedical field and roughly divide applications of PNPs into four categories: (1) Delivery, (2) In vivo imaging, (3) Therapies, and (4) Other applications. First, we introduce how PNPs can enhance the treatment and delivery efficiency of therapeutic agent. Second, how PNPs can be used to help in vivo imaging system for disease tracking and monitor. Then, we reveal some novel PNPs which is able to function as an agent in photodynamic, photothermal, sonodynamic and neuron capture therapy. Furthermore, we also mention some interesting applications of PNPs for biomedical field in individual form or cluster employment, such as immunoswitch particles, surface fabrication. Finally, the challenges and future development of PNPs are also discussed. In delivery section, we focus on how polymer "can be used" as vehicles in delivery application. But, in the section of imaging and therapies, we carried on how polymer as an "adjuvant" for functional enhancement. The biodegradable property of PNPs is the feature that they can be controllable for itself degradation and drug release as a chief actor. Besides, in imaging and therapies application, PNPs can be the support role for helping contrast agent or photo/sonosensitizer to enlarge their imaging or therapeutic effect.


Assuntos
Engenharia Biomédica/tendências , Nanopartículas , Polímeros , Meios de Contraste , Sistemas de Liberação de Medicamentos , Humanos , Fármacos Fotossensibilizantes
10.
Int J Mol Sci ; 19(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235809

RESUMO

Ocular drug delivery has been a major challenge for clinical pharmacologists and biomaterial scientists due to intricate and unique anatomical and physiological barriers in the eye. The critical requirement varies from anterior and posterior ocular segments from a drug delivery perspective. Recently, many new drugs with special formulations have been introduced for targeted delivery with modified methods and routes of drug administration to improve drug delivery efficacy. Current developments in nanoformulations of drug carrier systems have become a promising attribute to enhance drug retention/permeation and prolong drug release in ocular tissue. Biodegradable polymers have been explored as the base polymers to prepare nanocarriers for encasing existing drugs to enhance the therapeutic effect with better tissue adherence, prolonged drug action, improved bioavailability, decreased toxicity, and targeted delivery in eye. In this review, we summarized recent studies on sustained ocular drug/gene delivery and emphasized on the nanocarriers made by biodegradable polymers such as liposome, poly lactic-co-glycolic acid (PLGA), chitosan, and gelatin. Moreover, we discussed the bio-distribution of these nanocarriers in the ocular tissue and their therapeutic applications in various ocular diseases.


Assuntos
Administração Oftálmica , Portadores de Fármacos/química , Nanopartículas/química , Absorção Ocular , Animais , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/farmacocinética , Portadores de Fármacos/farmacocinética , Humanos , Injeções Intraoculares/métodos , Nanopartículas/metabolismo
11.
Neurosurg Focus ; 42(VideoSuppl1): V4, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28042725

RESUMO

There are many kinds of artificial discs available for cervical disc arthroplasty (CDA), with various designs of fixation and articulation mechanisms. Each of these designs has different features and theoretically fits most optimally in selected types of patients. However, there has been insufficient literature to guide individualized selection among these CDA devices. Since CDA aims to restore the joint function rather than arthrodesis, tailor-made size, shape, and mechanical properties should be taken into account for each candidate's target disc. Despite several large-scale prospective randomized control trials that have demonstrated the effectiveness and durability of CDA for up to 8 years, none of them involved more than one kind of artificial disc. In this video the authors present detailed steps and technical aspects of the newly introduced ProDisc-C Vivo (DePuy Synthes Spine), which has the same ball-and-socket design for controlled, predictable motion as the ProDisc-C. The newly derived teeth fixation provides high primary stability and multilevel capability by avoidance of previous keel-related limitations and complications (e.g., split vertebral fracture). Please note that the ProDisc-C Vivo is currently not available on the US market. The authors present the case of a 53-year-old woman who had symptoms of both radiculopathy and myelopathy caused by a large, calcified disc herniation at C4-5. There was no improvement after 4 months of medical treatment and rehabilitation. A single-level CDA was successfully performed with the ProDisc-C Vivo, and her symptoms were completely ameliorated afterward. The follow-up images demonstrated preservation of motion at the indexed level. The video can be found here: https://youtu.be/4DSES1xgvQU .


Assuntos
Deslocamento do Disco Intervertebral/cirurgia , Implantação de Prótese/métodos , Radiculopatia/cirurgia , Fusão Vertebral/métodos , Substituição Total de Disco/métodos , Vértebras Cervicais/cirurgia , Feminino , Humanos , Deslocamento do Disco Intervertebral/complicações , Pessoa de Meia-Idade , Radiculopatia/etiologia , Amplitude de Movimento Articular , Resultado do Tratamento
12.
Analyst ; 140(15): 5301-7, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26075380

RESUMO

A core-shell structured molecularly imprinted polymer on upconverting nanoparticles (UCNPs@MIP) was synthesized for the fluorescence (FL) sensing of sulfamethazine (SMZ). Hexagonal UCNPs were synthesized by the solvothermal method, then coated with a thin silica shell and modified with vinyl groups. Finally, surface polymerization was initiated among the vinyl groups, the functional monomers and cross-linking agents by the initiator. The MIP synthesized by this procedure was anchored on the surface of UCNPs, possessed better site accessibility and lower transfer resistance for the target molecule compared to bulk imprinted materials. The obtained UCNPs@MIP showed good binding capacity, fast response, high selectivity and specificity to the SMZ. The FL intensity of the UCNPs@MIP decreased sensitively with the increasing concentration of SMZ in the range of 50-700 ng mL(-1), the detection limit was 34 ng mL(-1) (S/N = 3). The UCNPs@MIP was successfully applied to the detection of SMZ in chicken samples. Thanks to the unique near-infrared (NIR) excitation nature of UCNPs, the chicken meat only needed some simple extraction procedures before FL detection, no complex purifications were required. The average recoveries ranged from 96.01% to 98.90%, with relative standard deviations (RSDs) below 4.5%. This work offers a novel sensing system that combined the advantages of upconverting nanotechnology and molecularly imprinted technology.


Assuntos
Anti-Infecciosos/análise , Carne/análise , Impressão Molecular , Nanopartículas/química , Polímeros/química , Espectrometria de Fluorescência , Sulfametazina/análise , Animais , Galinhas , Fluorescência , Limite de Detecção , Impressão Molecular/métodos , Nanopartículas/ultraestrutura , Espectrometria de Fluorescência/métodos
13.
Small ; 10(7): 1308-13, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24829962

RESUMO

A novel opal closest-packing (OCP) photonic crystal (PC) is successfully prepared for naked-eye glucose detection. This PC is fabricated via a vertical convective self-assembly method with a new type of monodisperse microsphere polymerized by co-monomers, namely, methyl methacrylate (MMA), N-isopropylacrylamide (NIPA), and 3-acrylamidophenylboronic acid (AAPBA). The OCP PC has high stability and periodically-ordered structure, showing the desired structural color. The proposed PC material displays a red shift and reduced reflection intensity when detecting glucose molecules. The red-shift wavelength reaches 75 nm, which clearly changes the structural color from brilliant blue to emerald green. This visually distinguishable color change facilitates the detection of the glucose concentrations from 3 to 20 mm, which demonstrates the potential of the opal PC material for naked-eye detection. Thus, the novel PMMA­NIPA­AAPBA OCP PC is a simply prepared and sensitive material, which shows promising use in the diagnosis of diabetes mellitus and in real-time monitoring of diabetes. Different types of appropriated recognition groups are expected to be introduced into the 3D OCP PC to form new functional materials or chemical sensors, which will extensively broaden the PC material application.


Assuntos
Glucose/análise , Fótons , Acrilamidas/química , Ácidos Borônicos/química , Cristalização , Concentração de Íons de Hidrogênio , Íons , Metais/análise , Microscopia Eletrônica de Varredura , Concentração Osmolar , Espectroscopia Fotoeletrônica , Polimetil Metacrilato/química , Reciclagem , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Chemistry ; 20(36): 11402-9, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25056685

RESUMO

A series of dual-metal zeolitic imidazolate framework (ZIF) crystals with SOD and RHO topologies was synthesised by metal substitution from ZIF-108 (Zn(2-nitroimidazolate)2 , SOD topology) as the parent material. This was based on the concept that metal substitution of ZIF-108 requires a much lower activation energy than homogenous nucleation owing to the metastability of ZIF-108. In-depth investigations of the formation processes of the daughter ZIFs indicated that the transformation of ZIF-108 is a dissolution/heterogeneous nucleation process. Typical isostructural Co(2+) substitution mainly occurs at the outer surface of ZIF-108 and results in a core-shell structure. On the contrary, the Cu(2+) -substituted ZIF has a RHO topology with a homogeneous distribution of Cu(2+) ions in the structure. Substitution with Ni(2+) resulted in a remarkable enhancement in adsorption selectivity toward CO(2) over N(2) by a factor of up to 227. With Co(2+) -substituted nanoparticles as inorganic filler, a mixed matrix membrane based on polysulfone displayed greatly improved performance in the separation of H(2)/CH(4), CO(2)/N(2) and CO(2)/CH(4).


Assuntos
Gases/isolamento & purificação , Imidazóis/química , Membranas Artificiais , Compostos Organometálicos/química , Zeolitas/química , Adsorção , Modelos Moleculares , Zinco/química
15.
Analyst ; 138(9): 2720-8, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23482908

RESUMO

Based on a combination of the molecular imprinting technique and polymerized crystalline colloidal array, we have developed an imprinted crystalline colloidal array (ICCA) chemical-sensing material for the real-time and label-free detection of diethylstilbestrol (DES) in aqueous solution. This novel sensing material was prepared by a noncovalent and self-assembly approach using liquid monodispersed DES-imprinted colloidal spheres and was characterized by a three-dimensional (3D) ordered opal structure in which numerous nanocavities were derived from DES imprinting. Thus, the inherent high affinity of the nanocavities allowed ICCA to recognize DES with high specificity, and changes of the ordered periodic structure enabled ICCA to transfer the recognition events into readable optical signals (label-free). Owing to the special opal structure and without interference from the bulk hydrogel film, the ICCA enabled the rapid and sensitive detection of the target analyte. The understanding of the recognizing response has also been advanced by using molecular modeling software to compute rational interaction between the template molecules and the function monomers. After careful optimization of the assay conditions, the ICCA could decrease its diffraction intensity within just 7 min according to the DES concentration from 2 ng mL(-1) to 8.192 µg mL(-1), whereas there were no obvious diffraction intensity changes for the DES analogues. The adsorption results showed that the homogenous structure and large surface area of ICCA could improve its adsorption capacity. Therefore, such a sensing material with high selectivity, high sensitivity, high stability, and easy operation might offer an attractive alternative for establishing optical sensors for the rapid real-time monitoring of different residues in food and the environment.


Assuntos
Carcinógenos/análise , Dietilestilbestrol/análise , Estrogênios não Esteroides/análise , Impressão Molecular , Adsorção , Coloides/química , Simulação por Computador , Modelos Moleculares , Polímeros/química , Sensibilidade e Especificidade , Espectrofotometria/métodos
16.
Shanghai Kou Qiang Yi Xue ; 32(6): 623-629, 2023 Dec.
Artigo em Zh | MEDLINE | ID: mdl-38494971

RESUMO

PURPOSE: To measure the cortical bone thickness of zygomatic alveolar ridge in adolescents and explore the correlation between cortical bone thickness and cervical vertebral bone age. METHODS: Cone-beam CT data of 80 adolescents were collected, including 20 adolescents with cervical vertebral bone ages of Cvs3, Cvs4, Cvs5 and Cvs6, respectively. CBCT images were reconstructed with the maxillary occlusal plane as the reference plane. Cortical bone thickness of different slices in the left maxillary zygomatic alveolar ridge area was measured in the direction parallel to and 60° from the reference plane, and the measured data were statistically analyzed by SPSS 21.0 software package. RESULTS: When the measurement direction was parallel to the reference plane and at 60°, the cortical bone thickness in the zygomatic alveolar ridge area of Cvs3-Cvs6 adolescents was (0.90±0.09) -(1.72±0.21) mm and (1.35±0.44)-(3.98±1.48) mm, respectively. There was significant difference in cortical bone thickness between Cvs4 and Cvs5 group(P<0.05). Spearman correlation analysis showed a strong positive correlation(P<0.01) between cortical bone thickness of zygomatic alveolar ridge and cervical vertebral bone age in adolescents. CONCLUSIONS: The cortical bone thickness of zygomatic alveolar ridge in adolescents increases with the increase of cervical vertebral bone age, and the cortical bone thickness may increase significantly during Cvs4-Cvs5. In terms of cortical bone thickness, all slices of zygomatic alveolar ridge of CVS3-CVS6 adolescents are suitable for implanting miniscrews, and the anterior slices should be selected for implantation as far as possible for Cvs3 and Cvs4 adolescents.


Assuntos
Processo Alveolar , Maxila , Humanos , Adolescente , Processo Alveolar/diagnóstico por imagem , Maxila/diagnóstico por imagem , Osso Cortical , Tomografia Computadorizada de Feixe Cônico/métodos
17.
Biosensors (Basel) ; 13(2)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36832041

RESUMO

Even with the widespread uptake of vaccines, the SARS-CoV-2-induced COVID-19 pandemic continues to overwhelm many healthcare systems worldwide. Consequently, massive scale molecular diagnostic testing remains a key strategy to control the ongoing pandemic, and the need for instrument-free, economic and easy-to-use molecular diagnostic alternatives to PCR remains a goal of many healthcare providers, including WHO. We developed a test (Repvit) based on gold nanoparticles that can detect SARS-CoV-2 RNA directly from nasopharyngeal swab or saliva samples with a limit of detection (LOD) of 2.1 × 105 copies mL-1 by the naked eye (or 8 × 104 copies mL-1 by spectrophotometer) in less than 20 min, without the need for any instrumentation, and with a manufacturing price of <$1. We tested this technology on 1143 clinical samples from RNA extracted from nasopharyngeal swabs (n = 188), directly from saliva samples (n = 635; assayed by spectrophotometer) and nasopharyngeal swabs (n = 320) from multiple centers and obtained sensitivity values of 92.86%, 93.75% and 94.57% and specificities of 93.22%, 97.96% and 94.76%, respectively. To our knowledge, this is the first description of a colloidal nanoparticle assay that allows for rapid nucleic acid detection at clinically relevant sensitivity without the need for external instrumentation that could be used in resource-limited settings or for self-testing.


Assuntos
COVID-19 , Nanopartículas Metálicas , Humanos , Colorimetria , Saliva , RNA Viral , SARS-CoV-2 , Ouro , Pandemias , Nasofaringe , Manejo de Espécimes
18.
J Bacteriol ; 194(8): 2117-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22461553

RESUMO

Paenibacillus sp. strain Aloe-11, a Gram-positive, spore-forming, facultatively anaerobic bacterium isolated from the root of Aloe chinensis in the southwest region of China, has excellent antibiotic activity and intestine colonization ability. Here, we present the 5.8-Mb draft genome sequence of Paenibacillus sp. strain Aloe-11.


Assuntos
Intestinos/microbiologia , Paenibacillus/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Celulose/metabolismo , Galinhas , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Camundongos , Dados de Sequência Molecular , Paenibacillus/classificação , Paenibacillus/metabolismo , Canais de Ânion Dependentes de Voltagem
19.
Analyst ; 137(19): 4571-6, 2012 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-22898662

RESUMO

A new surface-initiated polymerization based on pasting the initiator on a sensor chip surface was applied to prepare a malachite green (MG) imprinted ultrathin film on a surface plasmon resonance (SPR) sensor. First, the initiator (2,2-azoisobutyronitrile) was pasted on the gold surface using polyvinyl chloride (PVC). The initiator-covered gold chip was then soaked in a pre-polymerization solution prepared by dissolving methacrylic acid (functional monomer), ethylene glycol dimethacrylate (cross-linker), and MG (template) in DMSO in a weighing bottle. Finally, the weighing bottle was placed in a vacuum oven and thermal-initiated polymerization was conducted at 60 °C for 16 h. This method was simple and time-saving compared with the commonly used surface-initiated polymerization. More importantly, the molecularly imprinted polymer (MIP) film prepared using this method was much thicker than that of commonly used methods; the adsorption quantity was also much larger. The MIP modified SPR sensor showed high sensitivity and selectivity as well as good stability in detecting MG. The results suggest that the ultrathin MIP film prepared using the new method in this study is suitable to serve as the recognition element of the SPR sensor.


Assuntos
Impressão Molecular , Corantes de Rosanilina/química , Ressonância de Plasmônio de Superfície , Ouro/química , Nitrilas/química , Polimerização , Cloreto de Polivinila/química , Propriedades de Superfície
20.
Analyst ; 137(5): 1252-8, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22262283

RESUMO

A quartz crystal microbalance (QCM) sensor based on molecularly imprinted ultra-thin films was developed for detecting profenofos in real samples. Films prepared by physical entrapment (MIP-A) and in situ self-assembly (MIP-B) were compared. The results indicated that the best sensing signal was obtained through the in situ self-assembly method. The QCM sensor chip was pretreated with 11-mercaptoundecanoic acid (MUA) to form a self-assembled monolayer (SAM), and then polymer films were immobilized directly on the SAM using surface-initiated radical polymerization. In this paper, all detection experiments were taken in air. The reaction was processed in solution, and the electrode was washed with deionized water and dried with N(2) before QCM measurement. The film was characterized by a scanning electron microscope (SEM), AC impedance and cyclic voltammetry. Analysis of the QCM response in the presence of different concentrations of profenofos showed a good linear correlation during 1.0 × 10(-8) to 1.0 × 10(-5) mg mL(-1) (y = 5log x + 42.5, R = 0.9960) and 1.0 × 10(-5) to 1.0 × 10(-3) mg mL(-1) (y = 25.86log x + 146, R = 0.9959), respectively. The MIP-QCM sensor was used to detect profenofos in tap water, and showed good recovery and repeatability.


Assuntos
Impressão Molecular/métodos , Organotiofosfatos/análise , Resíduos de Praguicidas/análise , Polímeros/síntese química , Técnicas de Microbalança de Cristal de Quartzo/métodos , Ar/análise , Soluções Tampão , Eletrodos , Ácidos Graxos/química , Concentração de Íons de Hidrogênio , Nitrogênio/química , Organotiofosfatos/química , Compostos de Sulfidrila/química , Propriedades de Superfície , Água/química
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