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1.
Ibrain ; 10(2): 134-145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915947

RESUMO

This study aimed to evaluate the efficacy and safety of remimazolam for intraoperative sedation during regional anesthesia. It was a phase II-multicenter, randomized, single-blind, parallel-group, active-controlled clinical trial (No. ChiCTR2100054956). From May 6, 2021 to July 4, 2021, patients were randomly enrolled from 17 hospitals in China. A total of 105 patients aged 18-65 years who underwent selective surgery under regional anesthesia were included. Patients received different sedatives with different dosages: 0.1 mg/kg remimazolam (HR), 0.05 mg/kg remimazolam (LR), or 1.0 mg/kg propofol (P) group, followed by a maintenance infusion. Main outcome measures included the efficacy of sedation measured by Modified Observer's Assessment of Alertness/Sedation Scale (MOAA/S) levels (1-4, 1-3, 2-3, 3, and 2-4) during the sedation procedure (the duration percentage) and incidence of adverse reactions. It showed that the duration percentage of MOAA/S levels 1-4 was 100.0 [8.1]% (median [interquartile range]), 89.9 [20.2]%, 100.0 [7.7]% in the HR, LR, and P groups, respectively. The percentage of patients in the HR, LR, and P groups who achieved MOAA/S levels 1-4 within 3 min after administration was 85.7%, 58.8%, and 82.9%, respectively. However, the time to recovery from anesthesia after withdrawal of sedatives (7.9 ± 5.7 min), incidence of anterograde amnesia (75%), and adverse effects were not statistically significant among the three groups. These findings suggest that a loading dose of remimazolam 0.1 mg/kg followed by a maintenance infusion of 0-3 mg/kg/h provides adequate sedation for patients under regional anesthesia without increasing adverse reactions.

2.
Heliyon ; 10(10): e30684, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38770321

RESUMO

Upper-limb rehabilitation devices are essential in restoring and improving the motor function of hemiplegic patients. However, developing a product design that meets the needs of users is challenging. Current design tools and methods suffer from limitations such as a single model, poor synergy between integrated models, and subjective bias in analysing user needs and translating them into product attributes. To address these issues, this study proposes a new structural design decision-making model based on Behaviour Analysis (B), Failure Mode Effect Analysis (FMEA), and Teoriya Resheniya Izobreatatelskikh Zadatch (TRIZ theory). The model was developed and applied to design an upper-limb rehabilitation exoskeleton for hemiplegia. In this paper, an empirical investigation was conducted in several rehabilitation hospitals in Xuzhou City and used user journey mapping to identify potential failure points in the behaviour process. Then, the fault models were ranked according to the Fuzzy Risk Priority Number (FRPN) calculated by FMEA and used TRIZ theory to determine principles for resolving contradictions and generating creative design solutions for the product. By integrating B, FMEA, and TRIZ theory, it eliminated subjective bias in product design, improved the design decision-making process, and provided new methods and ideas for designing assistive rehabilitation devices and similar products. The framework of the proposed approach can be used in other contexts to develop effective and precise product designs that meet the needs of users.

3.
Phys Rev Lett ; 132(10): 106601, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518320

RESUMO

It has been theoretically predicted that perturbation of the Berry curvature by electromagnetic fields gives rise to intrinsic nonlinear anomalous Hall effects that are independent of scattering. Two types of nonlinear anomalous Hall effects are expected. The electric nonlinear Hall effect has recently begun to receive attention, while very few studies are concerned with the magneto-nonlinear Hall effect. Here, we combine experiment and first-principles calculations to show that the kagome ferromagnet Fe_{3}Sn_{2} displays such a magneto-nonlinear Hall effect. By systematic field angular and temperature-dependent transport measurements, we unambiguously identify a large anomalous Hall current that is linear in both applied in-plane electric and magnetic fields, utilizing a unique in-plane configuration. We clarify its dominant orbital origin and connect it to the magneto-nonlinear Hall effect. The effect is governed by the intrinsic quantum geometric properties of Bloch electrons. Our results demonstrate the significance of the quantum geometry of electron wave functions from the orbital degree of freedom and open up a new direction in Hall transport effects.

4.
Phys Rev Lett ; 132(5): 056301, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364160

RESUMO

Recent experiments reported an antisymmetric planar Hall effect, where the Hall current is odd in the in plane magnetic field and scales linearly with both electric and magnetic fields applied. Existing theories rely exclusively on a spin origin, which requires spin-orbit coupling to take effect. Here, we develop a general theory for the intrinsic planar Hall effect (IPHE), highlighting a previously unknown orbital mechanism and connecting it to a band geometric quantity-the anomalous orbital polarizability (AOP). Importantly, the orbital mechanism does not request spin-orbit coupling, so sizable IPHE can occur and is dominated by an orbital contribution in systems with weak spin-orbit coupling. Combined with first-principles calculations, we demonstrate our theory with quantitative evaluation for bulk materials TaSb_{2}, NbAs_{2}, and SrAs_{3}. We further show that AOP and its associated orbital IPHE can be greatly enhanced at topological band crossings, offering a new way to probe topological materials.

5.
Front Public Health ; 11: 1146318, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37325316

RESUMO

Background: Although the government has made a commitment to advance education on HIV disclosure, depression continues to play a significant role in whether people living with HIV (PLWH) choose to disclose their HIV status to families or friends. Vulnerable populations who are at risk of contracting HIV may also be more susceptible to mental illness. However, there is a limited understanding of the association between depression and vulnerable populations affects by HIV among United States adults. We aimed to explore the incidence of depression in the HIV infection vulnerable populations and assessed the association between the HIV infection vulnerable populations and depression. Methods: We analyzed the most current statistics from the National Health and Nutrition Examination Survey (NHANES) that included 16,584 participants aged 18 years or older between 1999 and 2018. The Patient Health Questionnaire-9 (PHQ-9) was used to evaluate symptoms of depressive disorder. Demographic characteristics were compared between the HIV infection vulnerable groups and HIV infection low-risk groups. Multivariable logistic regression analysis was also carried out to evaluate the odds rate and association between the HIV infection vulnerable populations and depression. Results: Based on the most recent statistics from NHANES, HIV infection vulnerable populations were male, younger, less married or living together, non-Hispanic White people, lower income, and lower body mass index (BMI), with higher levels of cigarette smoking, alcohol drinking, a higher prevalence of depression, lower prevalence of hypertension and diabetes mellitus (DM; p < 0.05). Additionally, individuals with severe depression had a higher prevalence of cardiovascular disease (CVD), hypertension, DM, chronic kidney disease (CKD), and a higher proportion of HIV infection vulnerable populations and less married or living together (p < 0.01). Finally, the odds of depression from the logistic regression were significantly increased in HIV infection vulnerable groups (p < 0.01). Conclusion: Depression might be associated with HIV infection vulnerable populations in the United States adults. More research is needed to evaluate the association between HIV infection vulnerable populations and depression and explore their causal associations. In addition, prevention efforts focusing on HIV disclosure and HIV infection vulnerable populations in the United States should address common co-prevalent depression to reduce new HIV infections.


Assuntos
Infecções por HIV , Hipertensão , Humanos , Adulto , Masculino , Estados Unidos/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , Inquéritos Nutricionais , Estudos Transversais , Depressão/epidemiologia , Populações Vulneráveis
6.
Brain Sci ; 13(4)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37190603

RESUMO

This study aimed to enhance the real-time performance and accuracy of vigilance assessment by developing a hidden Markov model (HMM). Electrocardiogram (ECG) signals were collected and processed to remove noise and baseline drift. A group of 20 volunteers participated in the study. Their heart rate variability (HRV) was measured to train parameters of the modified hidden Markov model for a vigilance assessment. The data were collected to train the model using the Baum-Welch algorithm and to obtain the state transition probability matrix A^ and the observation probability matrix B^. Finally, the data of three volunteers with different transition patterns of mental state were selected randomly and the Viterbi algorithm was used to find the optimal state, which was compared with the actual state. The constructed vigilance assessment model had a high accuracy rate, and the accuracy rate of data prediction for these three volunteers exceeded 80%. Our approach can be used in wearable products to improve their vigilance level assessment functionality or in other fields that have key positions with high concentration requirements and monotonous repetitive work.

7.
Phys Rev Lett ; 130(16): 166302, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37154629

RESUMO

We propose a time-reversal-even spin generation in second order of electric fields, which dominates the current induced spin polarization in a wide class of centrosymmetric nonmagnetic materials, and leads to a novel nonlinear spin-orbit torque in magnets. We reveal a quantum origin of this effect from the momentum space dipole of the anomalous spin polarizability. First-principles calculations predict sizable spin generations in several nonmagnetic hcp metals, in monolayer TiTe_{2}, and in ferromagnetic monolayer MnSe_{2}, which can be detected in experiment. Our work opens up the broad vista of nonlinear spintronics in both nonmagnetic and magnetic systems.

8.
Phys Rev Lett ; 130(12): 126303, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37027844

RESUMO

We propose an intrinsic nonlinear planar Hall effect, which is of band geometric origin, independent of scattering, and scales with the second order of electric field and first order of magnetic field. We show that this effect is less symmetry constrained compared with other nonlinear transport effects and is supported in a large class of nonmagnetic polar and chiral crystals. Its characteristic angular dependence provides an effective way to control the nonlinear output. Combined with first-principles calculations, we evaluate this effect in the Janus monolayer MoSSe and report experimentally measurable results. Our work reveals an intrinsic transport effect, which offers a new tool for material characterization and a new mechanism for nonlinear device application.

9.
Comput Intell Neurosci ; 2023: 2052231, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36793706

RESUMO

The application of human factors engineering for rehabilitation robots is based on a "human-centered" design philosophy that strives to provide safe and efficient human-robot interaction training for patients rather than depending on rehabilitation therapists. Human factors engineering for rehabilitation robots is undergoing preliminary investigation. However, the depth and breadth of current research do not provide a complete human factor engineering solution for developing rehabilitation robots. This study aims to provide a systematic review of research at the intersection of rehabilitation robotics and ergonomics to understand the progress and state-of-the-art research on critical human factors, issues, and corresponding solutions for rehabilitation robots. A total of 496 relevant studies were obtained from six scientific database searches, reference searches, and citation-tracking strategies. After applying the selection criteria and reading the full text of each study, 21 studies were selected for review and classified into four categories based on their human factor objectives: implementation of high safety, implementation of lightweight and high comfort, implementation of high human-robot interaction, and performance evaluation index and system studies. Based on the results of the studies, recommendations for future research are presented and discussed.


Assuntos
Robótica , Humanos , Robótica/métodos , Previsões
10.
Nat Commun ; 13(1): 7218, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36433968

RESUMO

Topological boundary states are well localized eigenstates at the boundary between two different bulk topologies. As long as bulk topology is preserved, the topological boundary mode will endure. Here, we report topological nonlinear parametric amplification of light in a dimerized coupled waveguide system based on the Su-Schrieffer-Heeger model with a domain wall. The good linear transmission properties of the topological waveguide arising from the strong localization of light to the topological boundary is demonstrated through successful high-speed transmission of 30 Gb/s non-return-to-zero and 56 Gb/s pulse amplitude 4-level data. The strong localization of a co-propagating pump and probe to the boundary waveguide is harnessed for efficient, low power optical parametric amplification and wavelength conversion. A nonlinear tuning mechanism is shown to induce chiral symmetry breaking in the topological waveguide, demonstrating a pathway in which Kerr nonlinearities may be applied to tune the topological boundary mode and control the transition to bulk states.

11.
J Clin Med ; 11(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362688

RESUMO

Objectives: For some patients, such as pregnant women, it can be difficult to maintain the ideal "forehead to knees" position for several minutes for epidural catheter placement. We conducted this study to investigate the feasibility of real-time ultrasound-guided (US) epidural catheterization under a comfortable lateral position without flexion of knees and neck. Materials and Methods: 60 patients aged 18-80 years with a body mass index of 18-30 kg/m2 after general surgery were included. In a comfortable left lateral position, thoracic epidural catheterization was performed under real-time US for postoperative analgesia. The visibility of the neuraxial structures, procedural time from needle insertion to loss of resistance in the epidural space, the number of needle redirections, success rate of epidural catheter placement and postoperative analgesic effect were recorded. Results: In the paramedian oblique sagittal view, the well visible of vertebral lamina, intervertebral space and posterior complex under ultrasound were as high as 93.33%, 81.67% and 70.00%, respectively. The success rate of thoracic epidural catheterization was as high as 91.67%, and the satisfactory postoperative analgesic effect was 98.2% for patients without nausea, pruritus and other discomfort. Discussion: Thoracic epidural catheterization with patients in the lateral position without flexion of knees and neck under real time ultrasound guidance has a high success rate and strong feasibility. This visual manipulation makes epidural catheterization not only "easier" to perform, but also reduces the requirements of the procedure.

12.
Phys Rev Lett ; 128(11): 116802, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363008

RESUMO

Symmetry plays a key role in modern physics, as manifested in the revolutionary topological classification of matter in the past decade. So far, we seem to have a complete theory of topological phases from internal symmetries as well as crystallographic symmetry groups. However, an intrinsic element, i.e., the gauge symmetry in physical systems, has been overlooked in the current framework. Here, we show that the algebraic structure of crystal symmetries can be projectively enriched due to the gauge symmetry, which subsequently gives rise to new topological physics never witnessed under ordinary symmetries. We demonstrate the idea by theoretical analysis, numerical simulation, and experimental realization of a topological acoustic lattice with projective translation symmetries under a Z_{2} gauge field, which exhibits unique features of rich topologies, including a single Dirac point, Möbius topological insulator, and graphenelike semimetal phases on a rectangular lattice. Our work reveals the impact when gauge and crystal symmetries meet together with topology and opens the door to a vast unexplored land of topological states by projective symmetries.

13.
Phys Rev Lett ; 127(27): 277202, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35061417

RESUMO

Response properties that are purely intrinsic to physical systems are of paramount importance in physics research, as they probe fundamental properties of band structures and allow quantitative calculation and comparison with experiment. For anomalous Hall transport in magnets, an intrinsic effect can appear at the second order to the applied electric field. We show that this intrinsic second-order anomalous Hall effect is associated with an intrinsic band geometric property-the dipole moment of Berry-connection polarizability (BCP) in momentum space. The effect has scaling relation and symmetry constraints that are distinct from the previously studied extrinsic contributions. Particularly, in antiferromagnets with PT symmetry, the intrinsic effect dominates. Combined with first-principles calculations, we demonstrate the first quantitative evaluation of the effect in the antiferromagnet Mn_{2}Au. We show that the BCP dipole and the resulting intrinsic second-order conductivity are pronounced around band near degeneracies. Importantly, the intrinsic response exhibits sensitive dependence on the Néel vector orientation with a 2π periodicity, which offers a new route for electric detection of the magnetic order in PT-invariant antiferromagnets.

14.
Phys Rev Lett ; 125(14): 143001, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064518

RESUMO

Unconventional Weyl points (WPs), carrying topological charge 2 or higher, possess interesting properties different from ordinary charge-1 WPs, including multiple Fermi arcs that stretch over a large portion of the Brillouin zone. Thus far, such WPs have been observed in chiral materials and acoustic metamaterials, but there has been no clean demonstration in photonics in which the unconventional photonic WPs are separated from trivial bands. We experimentally realize an ideal symmetry-protected photonic charge-2 WP in a three-dimensional topological chiral microwave metamaterial. We use field mapping to directly observe the projected bulk dispersion, as well as the two long surface arcs that form a noncontractible loop wrapping around the surface Brillouin zone. The surface states span a record-wide frequency window of around 22.7% relative bandwidth. We demonstrate that the surface states exhibit a novel topological self-collimation property and are robust against disorder. This work provides an ideal photonic platform for exploring fundamental physics and applications of unconventional WPs.

15.
Cancer Biomark ; 24(2): 159-172, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30614803

RESUMO

BACKGROUND: A growing body of studies have demonstrated the aberrant expression of microRNAs (miRNAs) contributes to human tumor metastasis. MicroRNA-124-3p (miR-124-3p), which is down-regulated in various cancers, has been found to be involved in several signaling pathways relevant to tumor cell migration and invasion. However, the roles of miR-124-3p in human bladder cancer remain unclear. This study aims to investigate the functional significance of miR-124-3p and to understand how it targets the integrin receptor, and thus affects the progression of human bladder cancer. METHODS: Clinical specimens from 36 patients and three human bladder cancer cell lines were analyzed for miR-124-3p and integrin α3 (ITGA3) . To investigate the effects of miR-124-3p and ITGA3 on proliferation of bladder cancer cells, the MTT assay, colon-formation assay and flow cytometry were performed. In addition, wound healing assay and transwell assay were carried out to examine the migration and invasion of the bladder cancer cells transfected with miR-124-3p mimics or si-ITGA3. The luciferase reporter assay, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were applied to validate the miR-124-3p directly binding with ITGA3. Finally, western blot was used to examine the expression level of the proteins involved in FAK/PI3K/AKT and FAK/Src signal pathway as well as epithelial-mesenchymal transition (EMT) process. RESULTS: The down-regulation of miR-124-3p and up-regulation of ITGA3 were observed in clinical specimens and bladder cancer cell lines. Overexpression of miR-124-3p or silencing ITGA3 inhibited tumor cell migration and invasion. Luciferase assay confirmed miR-124-3p directly targets ITGA3, and western blot suggested that miR-124-3p plays a crucial role in the EMT and metastasis of human bladder cancer through FAK/PI3K/AKT and FAK/Src signaling mechanism. Also, by targeting ITGA3, miR-124-3p can modulate the expression of N- and E-cadherin, and thus inhibit the EMT. CONCLUSIONS: By targeting ITGA3 and downstream FAK/PI3K/AKT and FAK/Src signaling pathways, miR-124-3p suppresses cell migration and invasion in bladder cancer. Our study reasonably speculates that miR-124-3p can be potentially developed as a therapeutic target and prognostic biomarker for bladder cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Integrina alfa3/metabolismo , Transdução de Sinais/genética , Neoplasias da Bexiga Urinária/patologia , Apoptose , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal , Proteínas da Matriz Extracelular , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Integrina alfa3/genética , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Ligação Proteica , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
16.
Biomed Mater ; 10(3): 035008, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26041143

RESUMO

In order to effectively immobilize and control release of basic fibroblast growth factor (bFGF) from alginate microspheres, heparin-conjugated alginate (H-Alg) was first synthesized by covalent binding. Then multilayered H-Alg microspheres (multilayered microspheres) were fabricated via an electrostatic droplet generation technique followed by a layer-by-layer (LbL) self-assembly technique. Several techniques such as Fourier transform infrared spectroscopy (FTIR), (1)H-NMR, zeta potential analysis and scanning electron microscopy (SEM) were used to characterize the properties of H-Alg (FTIR and (1)H-NMR) and multilayered microspheres (FTIR, zeta potential analysis and SEM). bFGF binding efficiency, release profiles of bFGF from multilayered microspheres and the biological activity of released bFGF were well investigated. It was found that the bFGF binding efficiency of H-Alg microspheres was increased up to five times higher than that of the alginate microspheres. Additionally, the release profiles of bFGF from multilayered microspheres were sustained for two weeks with relieved initial burst release, and the release rate to bFGF could be regulated by controlling the number of deposited layers. Importantly, the released bFGF still retained its biological activity as assessed by the in vitro proliferation of NIH-3T3 mouse fibroblasts. In conclusion, this study presented an easy yet effective method for the controlled, sustained release of heparin-binding growth factors, using polyelectrolyte multilayer-coated heparin-conjugated alginate microspheres.


Assuntos
Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Alginatos , Animais , Materiais Biocompatíveis , Proliferação de Células/efeitos dos fármacos , Preparações de Ação Retardada , Portadores de Fármacos/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Ácido Glucurônico , Heparina , Ácidos Hexurônicos , Espectroscopia de Ressonância Magnética , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Microesferas , Células NIH 3T3 , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
17.
Biomed Mater ; 8(5): 055007, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24057809

RESUMO

A soft and biocompatible hydrogel exhibiting a higher loading and the sustained release of gatifloxacin (GFLX) was developed as the potential matrix to fabricate a therapeutic contact lens for curing bacterial keratitis. 2-hydroxyethyl methacrylate (HEMA) and five other kinds of vinyl monomers with different side groups were used as co-monomers. Copolymerization took place in a cornea shaped mould via the gradient temperature-elevating method. The results of drug loading and in vitro release experiments showed that P(HEMA-co-MAA) achieved the highest drug loading of 11.78±0.77 µg mg(-1) among the obtained hydrogels, as well as a slow release. In addition, its physical properties and cytocompatibility were also proved suitable and safe for wearing on the eye surface. In animal experiments, a rat model of bacterial keratitis was established and employed to evaluate the clinical results of certain treatments employing obtained hydrogels; saline and GFLX eye drops were used as negative and positive controls, respectively. Corneal abscess and opacity caused by epithelial erosion and stromal ulceration were almost healed after wearing the drug loaded P(HEMA-co-MAA) hydrogel for 48 h. Its excellent antibacterial effect was also confirmed by testing the bacterial activity in tear extraction via the streak line method.


Assuntos
Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Lentes de Contato , Portadores de Fármacos , Fluoroquinolonas/administração & dosagem , Hidrogéis/química , Ceratite/tratamento farmacológico , Animais , Infecções Bacterianas/microbiologia , Linhagem Celular , Gatifloxacina , Humanos , Ceratite/microbiologia , Metacrilatos/química , Polímeros/química , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
18.
Biomed Mater ; 7(3): 035012, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22475630

RESUMO

In this study, calcium-alginate microgels coated with a polyelectrolyte multilayer (PEM) were fabricated as a controlled-release system. This system was constructed via an electrostatic droplet generation technique followed by a layer-by-layer (LbL) self-assembly technique. The electrostatic droplet generation technique was reported as an easy method of preparing microgels, due to their mild preparation conditions and ability to preserve the biological activity of the encapsulated drugs. With the LbL self-assembly technique, the PEM could be fabricated on the microgels attributed to the electrostatic attraction between positive-charged chitosan (Chi) and negative-charged dextran sulfate (Dex). The properties of the prepared microgels were investigated using dynamic laser scattering (DLS), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectrum and zeta potential analyzer. In vitro release study indicated that the initial burst release of the bovine serum albumin (BSA) from PEM-coated microgels was less compared to the uncoated microgels (19% versus 31% in 24 h). In addition, the sustained release of BSA from the PEM-coated microgels was recorded up to 1 month without any damage to BSA integrity. Thus, our results demonstrated that the PEM-coated microgels not only prolonged the release time, but also relieved the initial burst problem to some degree and preserved the biological activity of the encapsulated drugs. Moreover, the release rate of BSA could be regulated by controlling the number of deposited layers. In conclusion, this study presented an easy yet effective method for the controlled, sustained release of biological macromolecules.


Assuntos
Alginatos/química , Materiais Revestidos Biocompatíveis/síntese química , Preparações de Ação Retardada/química , Eletrólitos/química , Géis/química , Soroalbumina Bovina/química , Animais , Bovinos , Difusão , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Teste de Materiais
19.
Recent Pat Drug Deliv Formul ; 5(3): 265-74, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21834779

RESUMO

Intelligent hydrogel, also known as smart hydrogels, are materials with great potential for development in drug delivery system. Intelligent hydrogel also has the ability to perceive as a signal structure change and stimulation. The review introduces the temperature-, pH-, electric signal-, biochemical molecule-, light- and pressure- sensitive hydrogels. Finally, we described the application of intelligent hydrogel in drug delivery system and the recent patents involved for hydrogel in drug delivery.


Assuntos
Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Animais , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Composição de Medicamentos/tendências , Sistemas de Liberação de Medicamentos/tendências , Técnicas Eletroquímicas , Humanos , Hidrogéis , Concentração de Íons de Hidrogênio , Luz , Patentes como Assunto , Transição de Fase , Pressão , Temperatura
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