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1.
Ecotoxicol Environ Saf ; 255: 114818, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36958263

RESUMO

Microplastics (MPs) are one novel environmental pollutant sized < 5 mm that is ubiquitously present in numerous environmental media and particularly susceptible to interact with various toxic chemicals. Importantly, MPs can enter the food chain, and are bio-enriched and bio-accumulated with trophic levels, eventually endangering ecosystems and human health. However, there need to be more understanding regarding the bio-interaction of MPs with the host, particularly for biological barriers. This review aimed to summarize the latest findings regarding the main exposure routes of MPs that generated health burdens on humans. Furthermore, their interactions with biological barriers that generate adverse health effects and the underlying mechanisms were also reviewed. Additionally, we provided a comprehensive overview of recent advances regarding the removing and controlling of MPs. Finally, we discussed the future directions for MPs hazard prevention to provide helpful information for regulating decision-making and guiding safer plastics applications.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Poluentes Ambientais , Humanos , Microplásticos/toxicidade , Plásticos , Ecossistema , Poluição Ambiental
2.
Environ Res ; 214(Pt 2): 113819, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35863441

RESUMO

Large-scale increases in plastic waste, greenhouse gas emissions, and fossil fuel depletion all have negative consequences for the environment. Plastic pollution can lead towards negative impacts on outdoor recreational activities. China and the European Union, as world leader in recycling and reuse, are tackling this issue by putting in place measures to counteract this trend for better outdoor recreational activities. As China and EU nations are most attracted by the tourists it is possible that recreational spot can have harmful effects upon wild and human life. So, we analyze the impacts of plastic waste recycling and reuse on outdoor recreation. It is possible to speed up the circular process if industry reduces its resource and energy consumption while also being able to handle plastic waste responsibly, utilize renewable energy sources, generate jobs, and contribute to economic growth, among other things. This research investigates the transition to sustainability in the European Union nations and China between 2000 and 2020 via the prism of resource and energy productivity in the EU nations and China. The Autoregressive Distributed Lag (ARDL) Model, as well as the estimator Driscool Kraay, are employed in this study. There is a statistically significant relationship between plastic recycling and valorization because of plastic pollution leads toward negative impacts on outdoor recreation, as well as resource productivity, according to the data. Increased energy tariffs, insufficient investment in research and development, a lack of job opportunities, and other factors all act as roadblocks to the implementation of circular growth strategies.


Assuntos
Plásticos , Gerenciamento de Resíduos , Desenvolvimento Econômico , Poluição Ambiental , Humanos , Recreação , Reciclagem
3.
J Sep Sci ; 45(14): 2687-2698, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35579607

RESUMO

In this study, monodisperse magnetic carbon microspheres were successfully synthesized through the carbonization of phenolic resin encapsulated Fe3 O4 core-shell structures. The magnetic carbon microspheres showed high performance in ultrafast extraction and separation of trace triazine herbicides from environmental water samples. Under optimized conditions, both the adsorption and desorption processes could be achieved in 2 min, and the maximum adsorption capacity for simazine and prometryn were 387.6 and 448.5 µg/g. Coupled with high-performance liquid chromatography-ultraviolet detection technology, the detection limit of triazine herbicides was in the range of 0.30-0.41 ng/mL. The mean recoveries ranged from 81.44 to 91.03% with relative standard deviations lower than 7.47%. The excellent magnetic solid-phase extraction performance indicates that magnetic carbon microspheres are promising candidate adsorbents for the fast analysis of environmental contaminants.


Assuntos
Herbicidas , Triazinas , Adsorção , Carbono , Cromatografia Líquida de Alta Pressão , Formaldeído , Herbicidas/análise , Limite de Detecção , Fenômenos Magnéticos , Microesferas , Fenóis , Polímeros , Extração em Fase Sólida , Triazinas/análise
4.
Sensors (Basel) ; 21(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208691

RESUMO

Fatigue cracks are critical types of damage in steel structures due to repeated loads and distortion effects. Fatigue crack growth may lead to further structural failure and even induce collapse. Efficient and timely fatigue crack detection and segmentation can support condition assessment, asset maintenance, and management of existing structures and prevent the early permit post and improve life cycles. In current research and engineering practices, visual inspection is the most widely implemented approach for fatigue crack inspection. However, the inspection accuracy of this method highly relies on the subjective judgment of the inspectors. Furthermore, it needs large amounts of cost, time, and labor force. Non-destructive testing methods can provide accurate detection results, but the cost is very high. To overcome the limitations of current fatigue crack detection methods, this study presents a pixel-level fatigue crack segmentation framework for large-scale images with complicated backgrounds taken from steel structures by using an encoder-decoder network, which is modified from the U-net structure. To effectively train and test the images with large resolutions such as 4928 × 3264 pixels or larger, the large images were cropped into small images for training and testing. The final segmentation results of the original images are obtained by assembling the segment results in the small images. Additionally, image post-processing including opening and closing operations were implemented to reduce the noises in the segmentation maps. The proposed method achieved an acceptable accuracy of automatic fatigue crack segmentation in terms of average intersection over union (mIOU). A comparative study with an FCN model that implements ResNet34 as backbone indicates that the proposed method using U-net could give better fatigue crack segmentation performance with fewer training epochs and simpler model structure. Furthermore, this study also provides helpful considerations and recommendations for researchers and practitioners in civil infrastructure engineering to apply image-based fatigue crack detection.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Fadiga , Aço
5.
Appl Microbiol Biotechnol ; 99(8): 3629-37, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25511823

RESUMO

2,4-Dichlorophenol (2,4-DCP) is considered as an important pollutant because of its high toxicity and wide distribution in wastewaters. Innocuous remediation technologies have been studied for the removal of this pollutant. This study investigated the feasibility of using garlic roots as a plant system for the removal of 2,4-DCP. The optimal conditions for its removal were established based on orthogonal experiments (OA25 matrix). Significant factors that affect removal efficiency, arranged from high to low importance, include pH, reaction time, 2,4-DCP concentration, and H2O2 concentration. In addition, garlic roots could be re-used for as much as three consecutive cycles. The decrease in pH and the increase of Cl(-) ion content in the post-removal solutions indicated that 2,4-DCP dehalogenation occurred during transformation. Changes in the deposition pattern of lignin in roots exposed to 2,4-DCP suggested that several of the products deposited were lignin-type polymers. The acute toxicity test revealed that the post-removal solutions were less toxic than the parent solutions. Therefore, garlic roots have considerable potential to effectively and safely remove 2,4-DCP from wastewater.


Assuntos
Biodegradação Ambiental , Clorofenóis/metabolismo , Alho/metabolismo , Raízes de Plantas/metabolismo , Poluentes Químicos da Água/metabolismo , Biotransformação , Lignina/metabolismo , Soluções/metabolismo
6.
Heliyon ; 10(15): e35449, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39170175

RESUMO

Foot-and-mouth disease virus (FMDV) 2C protein is a conserved non-structural protein and crucial for replication of the virus. In this study, FMDV 2C protein was prepared and the enzymatic activities were investigated in detail. The protein could digest ssDNA or ssRNA into a small fragment at about 10 nt, indicating that the protein has nuclease activity. But it did not show digestion to blunt-end dsDNA or dsRNA. The nuclease activity of 2C protein could be inhibited in 2 mM Zn2+ or Ca2+ while enhanced by Mg2+ or Mn2+. FMDV 2C protein exhibited unwinding activity to all the three kinds of dsDNA and dsRNA (5' protruded, 3' protruded, and blunt-end). The unwinding velocity to 5' protruded dsRNA was higher than to the blunt-end dsRNA. 2C protein only showed unwinding activity in high concentration of Mg2+, but no unwinding activity in physiological concentrations of Mg2+ and Ca2+, as well as in cell lysate. The 2C protein could catalyze two structured ssRNA to form double strand, thus it was proved to have RNA chaperone activity. The Mg2+ and ATP in different concentrations did not show promotion to the RNA chaperone activity. Finally, six mutant proteins (K116A, D160A, D170A, N207A, R226A, and F316A) were constructed and the enzymatic activities were analyzed. All the six mutations reduced the ATPase activity, D170A and F361A could inactivate the nuclease activity, while the N207A and F316A could inactivate the helicase activity. Our study provides a comprehensive understanding of the enzymatic activities of FMDV 2C protein.

7.
Int J Biol Macromol ; 275(Pt 1): 133630, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38969032

RESUMO

A flexible phase-change film with thermal management and microwave absorption capabilities was developed for use in wearable devices. The film was created using a solution casting method based on a porous carbon-loaded eicosane (LP33/EI) material. LP33 served as the porous encapsulation medium, while Eicosane (EI) acted as the phase change component. The flexible substrate was a blend of polyvinyl alcohol (PVA) and bacterial cellulose nanocellulose (BC). The ultrathin film had a thickness of 0.262 mm, and LP33/EI-4 exhibited exceptional mechanical strength of 188 MPa. Testing revealed that the phase transition process had melting and crystallization enthalpies of 134.71 J/g and 126.11 J/g, respectively. The encapsulation structure effectively prevented any leakage during the phase transition process. Under simulated solar irradiation of 200 mW/cm2, LP33/EI-4 achieved a photothermal conversion efficiency (η) of 89.46 %. Additionally, the porous LP33 structure and high dielectric loss contributed to remarkable microwave absorption capabilities of -42 dB in the X-band and - 52 dB in the Ku-band. Overall, LP33/EI films demonstrated exceptional performance in thermal management, energy storage, and microwave absorption, making them an ideal choice for a variety of applications in wearable devices.


Assuntos
Carbono , Lignina , Micro-Ondas , Dispositivos Eletrônicos Vestíveis , Porosidade , Carbono/química , Lignina/química , Transição de Fase , Temperatura , Celulose/química , Álcool de Polivinil/química
8.
Biosens Bioelectron ; 222: 114999, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36521206

RESUMO

Electronic textiles are fundamentally changing the way we live. However, the inability to effectively recycle them is a considerable burden to the environment. In this study, we developed a cotton fiber-based piezoresistive textile (CF p-textile) for biomonitoring which is biocompatible, biodegradable, and environmentally friendly. These CF p-textiles were fabricated using a scalable dip-coating method to adhere MXene flakes to porous cotton cellulose fibers. The adhesion is made stronger by strong hydrogen bonding between MXene flakes and hierarchically porous cotton cellulose fibers. This cotton-fiber system provides a high sensitivity of 17.73 kPa-1 in a wide pressure range (100 Pa-30 kPa), a 2 Pa subtle pressure detection limit, fast response/recovery time (80/40 ms), and good cycle stability (over 5, 000 cycles). With its compelling sensing performance, the CF p-textile can detect various human biomechanical activities, including pulsation, muscle movement, and swallowing, while still being comfortable to wear. Moreover, the cotton cellulose is decomposed into low-molecular weight cellulose or glucose as a result of the 1,4-glycosidic bond breakage when exposed to acid or during natural degradation, which allows the electronic textile to be biodegradable. This work offers an ecologically-benign, cost-effective and facile approach to fabricating high-performance wearable bioelectronics.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Humanos , Fibra de Algodão , Monitoramento Biológico , Têxteis , Celulose
9.
Mol Biol Rep ; 39(2): 1601-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21604170

RESUMO

A cDNA encoding an O-methyltransferase (namely FGCOMT1) was identified from the medicinal plant Trigonella foenum-graecum L. The FGCOMT1 enzyme is a functional caffeic acid O-methyltransferase (COMT) and is localized in the cytosol. Kinetic analysis indicated that FGCOMT1 protein exhibited the highest catalyzing efficiency towards 5-hydroxy ferulic acid and caffeic acid as substrates, but did not possess the abilities to methylate either quercetin or tricetin in vitro. Furthermore, transformation of Arabidopsis loss-of-function Atomt1 mutant with a FGCOMT1 cDNA partially complements accumulation of sinapoyl derivatives but did not function to produce the major methylated flavonol isorhamnetin in seeds. The results from this study indicated that FGCOMT1 is a COMT with substrate preference to monomeric lignin precursors but is not involved in the flavonoid methylation in T. foenum-graecum L.


Assuntos
Metiltransferases/genética , Modelos Moleculares , Filogenia , Trigonella/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Ácidos Cafeicos/metabolismo , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Ácidos Cumáricos/metabolismo , Primers do DNA/genética , DNA Complementar/genética , Flavonoides/biossíntese , Flavonoides/química , Teste de Complementação Genética , Cinética , Lignina/biossíntese , Lignina/química , Metiltransferases/química , Metiltransferases/metabolismo , Dados de Sequência Molecular , Estrutura Molecular , Sementes/metabolismo , Análise de Sequência de DNA
10.
Yao Xue Xue Bao ; 47(3): 393-8, 2012 Mar.
Artigo em Zh | MEDLINE | ID: mdl-22645765

RESUMO

The amino group PEGylation of rhIFNomega with monomethoxy polyethylene glycol succinimidyl succinate (mPEG-SS, 20 000) was investigated, and the modified mixture was separated and purified by ion exchange chromatography and gel filtration chromatography. Under the optimized purification conditions, the average content ofmono PEG-rhIFNomega in the collect liquid reached 182 microg x mL(-1). The average purified yield of mono PEG-rhIFNomega exceed to 22%, and the purity of mono PEG-rhIFNomega was greater than 98% by SDS-PAGE and RP-HPLC. Relative molecular mass of mono PEG-rhIFNomega was 43 790 detected by MALDI-TOF MS. The apparent molecular mass measured by SDS-PAGE was about 60 810. The purified PEG-rhIFNomega has the characteristics of typical PEGylated protein. Activity reservation rate of mono PEG-rhIFNomega was 15.0%, while the antigenicity decreased by at least 64 folds. In addition, the acid stability, thermal stability and stability in serum and trypsin solution of mono PEG-rhIFNomega were markedly better than those of the rhIFNomega. The pharmacological properties of mono PEG-rhIFNomega were significantly improved. The prepared PEG-rhIFNomega might be developed to a novel safe and long-acting interferon.


Assuntos
Interferon Tipo I/química , Polietilenoglicóis/química , Animais , Reações Antígeno-Anticorpo , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Estabilidade de Medicamentos , Eletroforese em Gel de Poliacrilamida , Interferon Tipo I/imunologia , Peso Molecular , Coelhos , Proteínas Recombinantes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Zhonghua Yi Xue Za Zhi ; 92(41): 2909-12, 2012 Nov 06.
Artigo em Zh | MEDLINE | ID: mdl-23328238

RESUMO

OBJECTIVE: To explore the clinical outcomes of surgical treatment for traumatic cervical disc herniation with MC + PEEK cage. METHODS: A total of 51 patients with traumatic cervical disc herniation in mono-segment were surgically treated. The patients in group A (n = 20) were treated by MC + PEEK cage while those in group B (n = 31) by anterior cervical plate with PEEK cage or titanium mesh. Various parameters of operative duration, blood loss volume, operative complications, bone union, height of intervertebral space and Japanese Orthopedic Association (JOA) score were recorded and compared. RESULTS: Fifty-one patients were followed up for an average time of 26 months (range: 6 - 40). Operative duration, blood loss volume and operative complications of group A were better than group B with statistical significance (P < 0.05). Bone union, height of intervertebral space and recovery of spinal cord function were satisfactory with no statistical difference (P > 0.05). CONCLUSION: With this new cage, traumatic cervical disc herniation may be safely and micro-invasively treated without the need of anterior cervical plate.


Assuntos
Vértebras Cervicais/cirurgia , Deslocamento do Disco Intervertebral/cirurgia , Fusão Vertebral/instrumentação , Adulto , Idoso , Benzofenonas , Materiais Biocompatíveis/uso terapêutico , Feminino , Humanos , Cetonas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Polímeros
12.
Int J Biol Macromol ; 213: 134-144, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35636529

RESUMO

Lignin-based porous carbon (LTC), lignin-based hierarchical porous carbon (LTCA) and lignin-based ordered porous carbon (MC) with different pore structures were prepared by template method and chemical activation method using lignin as raw material. The lignin-based carbon composite phase change materials were prepared by vacuum impregnation with polyethylene glycol (PEG) and porous carbon material. The results showed that LTCA has the largest loading capacity of Phase change Materials, which could load 85% of PEG; MC has the largest phase transition enthalpy value (ΔHm), which is 89.7 J·g-1. When the loading amount is the same as 60%, the thermal conductivity of LTCA/PEG is the largest, which is 0.5167 W/mK, 53.8% higher than that of pure PEG. Under constant heating at 70 °C, the pure cotton fabric and the polyurethane coated fabric reached 60 °C in the 4th and 10th second, The cotton fabric coated with composite phase change material reached 60 °C only at 16 s, and a significant slowdown in the temperature rise rate occurred between 50-60 °C. It showed that the cotton fabric coated with composite phase change material had good phase change temperature regulation performance.


Assuntos
Carbono , Lignina , Carbono/química , Lignina/química , Polietilenoglicóis/química , Condutividade Térmica , Termodinâmica
13.
Adv Sci (Weinh) ; 9(13): e2105550, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35277947

RESUMO

Piezoelectric nanocomposites with oxide fillers in a polymer matrix combine the merit of high piezoelectric response of the oxides and flexibility as well as biocompatibility of the polymers. Understanding the role of the choice of materials and the filler-matrix architecture is critical to achieving desired functionality of a composite towards applications in flexible electronics and energy harvest devices. Herein, a high-throughput phase-field simulation is conducted to systematically reveal the influence of morphology and spatial orientation of an oxide filler on the piezoelectric, mechanical, and dielectric properties of the piezoelectric nanocomposites. It is discovered that with a constant filler volume fraction, a composite composed of vertical pillars exhibits superior piezoelectric response and electromechanical coupling coefficient as compared to the other geometric configurations. An analytical regression is established from a linear regression-based machine learning model, which can be employed to predict the performance of nanocomposites filled with oxides with a given set of piezoelectric coefficient, dielectric permittivity, and stiffness. This work not only sheds light on the fundamental mechanism of piezoelectric nanocomposites, but also offers a promising material design strategy for developing high-performance polymer/inorganic oxide composite-based wearable electronics.


Assuntos
Nanocompostos , Eletrônica , Aprendizado de Máquina , Óxidos , Polímeros
14.
Small Methods ; 6(2): e2101051, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35174985

RESUMO

Electrode microfabrication technologies such as lithography and deposition have been widely applied in wearable electronics to boost interfacial coupling efficiency and device performance. However, a majority of these approaches are restricted by expensive and complicated processing techniques, as well as waste discharge. Here, helium plasma irradiation is employed to yield a molybdenum microstructured electrode, which is constructed into a flexible piezoresistive pressure sensor based on a Ti3 C2 Tx nanosheet-immersed polyurethane sponge. This electrode engineering strategy enables the smooth transition between sponge deformation and MXene interlamellar displacement, giving rise to high sensitivity (1.52 kPa-1 ) and good linearity (r2  = 0.9985) in a wide sensing range (0-100 kPa) with a response time of 226 ms for pressure detection. In addition, both the experimental characterization and finite element simulation confirm that the hierarchical structures modulated by pore size, plasma bias, and MXene concentration play a crucial role in improving the sensing performance. Furthermore, the as-developed flexible pressure sensor is demonstrated to measure human radial pulse, detect finger tapping, foot stomping, and perform object identification, revealing great feasibility in wearable biomonitoring and health assessment.


Assuntos
Desenho de Equipamento/métodos , Determinação da Frequência Cardíaca/instrumentação , Dispositivos Eletrônicos Vestíveis , Análise de Elementos Finitos , Humanos , Microtecnologia , Poliuretanos/química , Titânio/química , Tato
15.
Nat Commun ; 13(1): 4867, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982033

RESUMO

Polymer-ceramic piezoelectric composites, combining high piezoelectricity and mechanical flexibility, have attracted increasing interest in both academia and industry. However, their piezoelectric activity is largely limited by intrinsically low crystallinity and weak spontaneous polarization. Here, we propose a Ti3C2Tx MXene anchoring method to manipulate the intermolecular interactions within the all-trans conformation of a polymer matrix. Employing phase-field simulation and molecular dynamics calculations, we show that OH surface terminations on the Ti3C2Tx nanosheets offer hydrogen bonding with the fluoropolymer matrix, leading to dipole alignment and enhanced net spontaneous polarization of the polymer-ceramic composites. We then translated this interfacial bonding strategy into electrospinning to boost the piezoelectric response of samarium doped Pb (Mg1/3Nb2/3)O3-PbTiO3/polyvinylidene fluoride composite nanofibers by 160% via Ti3C2Tx nanosheets inclusion. With excellent piezoelectric and mechanical attributes, the as-electrospun piezoelectric nanofibers can be easily integrated into the conventional shoe insoles to form a foot sensor network for all-around gait patterns monitoring, walking habits identification and Metatarsalgi prognosis. This work utilizes the interfacial coupling mechanism of intermolecular anchoring as a strategy to develop high-performance piezoelectric composites for wearable electronics.


Assuntos
Nanofibras , Polímeros
16.
Ophthalmology ; 118(6): 1049-54, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21292327

RESUMO

PURPOSE: To evaluate the safety and clinical efficacy of fibrin glue in pterygium surgery with conjunctival autografting. DESIGN: The use of fibrin glue has been introduced in the treatment of pterygium. However, its role versus traditional suturing is still a matter of debate. We performed a meta-analysis to compare the safety and clinical efficacy of fibrin glue with suture for conjunctival autograft attachment in pterygium surgery. PARTICIPANTS: A total of 342 participants with 366 eyes in 7 studies were analyzed. METHODS: We searched Medline, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, and Google Scholar for relevant randomized controlled trials (RCTs). MAIN OUTCOME MEASURES: The methodological quality of all the included trials was assessed with the Jadad score. The meta-analysis was performed with the fixed-effects model for complication rate and recurrence rate, and random-effects model for operating time. RESULTS: Fibrin glue was associated with a significantly decreased operating time (weighted mean difference -17.61 minutes, 95% confidence interval [CI], -26.03 to -9.18, P<0.0001) and was more effective in reducing the recurrence rate (Peto odds ratio [OR] 0.33, 95% CI, 0.15-0.71, P = 0.004) compared with suture. There were no significant differences in the complication rate (Peto OR 1.82, 95% CI, 0.63-5.27, P = 0.27) between the 2 groups. CONCLUSIONS: Our meta-analysis supports the superiority of fibrin glue to suture in pterygium surgery with conjunctival autografting in that the use of fibrin glue can significantly reduce the recurrence rate without increasing the risk of complications. Ophthalmologists should consider the use of fibrin glue in pterygium surgery. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Assuntos
Túnica Conjuntiva/transplante , Adesivo Tecidual de Fibrina/uso terapêutico , Pterígio/cirurgia , Técnicas de Sutura/instrumentação , Suturas , Adesivos Teciduais/uso terapêutico , Humanos , Transplante Autólogo
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(6): 831-4, 2011 Nov.
Artigo em Zh | MEDLINE | ID: mdl-22332553

RESUMO

OBJECTIVE: To evaluate the biomechanic changes of craniofacial complex with rapid maxillary expansion using implant anchorage. METHODS: Rapid maxillary expansion using implant anchorage was simulated with MSC. Marc. Mentat software, restrained at the region around the foramen magnum and the anterior middle point of parietale and foramen. In the area of implant surface, forces of 80 N were applied with rapid maxillary expansion. Different numbers and positions of implant anchorage were chosen. Their influences on the craniofacial complex were analysed. RESULTS: The stress distribution and displacement trend of the craniofacial complex under different conditions were approximate. The greatest stress appeared on the areas along the frontonasal suture, zygomaticomaxillary suture, nasomaxillary suture and pterygopalatal suture. Two halves of palatine were separated in a "V" shape. Maximal stress and displacement were found when the implant was located between maxillary canine and first premolar. CONCLUSION: The numbers of implant are not associated with the size of stress and displacement. Greater stress and displacement occur when the implant position is in the front.


Assuntos
Análise de Elementos Finitos , Má Oclusão/terapia , Procedimentos de Ancoragem Ortodôntica/métodos , Técnica de Expansão Palatina , Fenômenos Biomecânicos , Humanos
18.
Adv Healthc Mater ; 10(17): e2100460, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34050624

RESUMO

This review summarizes recent progress in the use of biological materials (biomaterials) in wearable pressure sensors. Biomaterials are abundant, sustainable, biocompatible, and biodegradable. Especially, many have sophisticated hierarchical structure and biological characteristics, which are attractive candidates for facile and ecologically-benign fabrication of wearable pressure sensors that are biocompatible, biodegradable, and highly sensitivity. The biomaterials and structures that use them in wearable pressure sensors that exploit sensing mechanisms such as piezoelectric, triboelectric, piezoresistive and capacitive effects are present. Finally, remaining impediments are discussed to use of biomaterials in wearable pressure sensors.


Assuntos
Dispositivos Eletrônicos Vestíveis , Materiais Biocompatíveis
19.
Sci Total Environ ; 790: 148085, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34111795

RESUMO

Toxicological data demonstrate that nanoplastics (NPs) can cause direct adverse health effects. However, a method for quantifying NPs in biological samples is lacking to date. In this study, a diatomite associated coagulation-sedimentation extraction (CSE) protocol was developed to selectively enrich polystyrene nanoplastics (PS-NP) from microplastics (PS-MP) in the digest of animal tissues, which were then analyzed using pyrolysis gas chromatography-mass spectrometry. We demonstrate that 0.02 g of 7-µm diatomite can selectively adsorb 70-nm PS-NP in 5 mL oyster digest. The method works in the range of 0.006-5 µg PS-NP per 0.5 g wet weight tissue, which has been verified via samples of environmentally contaminated oysters and chow diet PS-NP-treated C57BL/6 mice (digestive tract, kidney, and liver tissues). The particle size-dependent colloidization or buoyancy theoretically supported the general CSE procedure. This work will pave the way for assessing human exposure to NPs and associated health risks.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Microplásticos , Plásticos , Poliestirenos/análise , Poluentes Químicos da Água/análise
20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(8): 1007-1013, 2021 Aug 15.
Artigo em Zh | MEDLINE | ID: mdl-34387430

RESUMO

OBJECTIVE: To evaluate the feasibility and short-term effectiveness of bilateral percutaneous balloon kyphoplasty through unilateral transverse process-extrapedicular approach for osteoporotic vertebral compression fracture (OVCF) of lumbar. METHODS: A retrospective analysis was made on the clinical data of 93 patients with OVCF of lumbar who met the selection criteria between January 2018 and June 2019. According to the different surgical methods, they were divided into group A (44 cases, treated with bilateral percutaneous balloon kyphoplasty through unilateral transverse process-extrapedicular approach) and group B [49 cases, treated with percutaneous kyphoplasty (PKP) via bilateral transpedicle approach]. There was no significant difference in gender, age, body mass index, T value of bone mineral density, injury cause, fractured level, time from injury to operation, comorbidities, and preoperative Cobb angle of injured vertebra, visual analogue scale (VAS) score, and Oswestry disability index (ODI) between the two groups ( P>0.05). The operation time, intraoperative fluoroscopy times, bone cement injection amount, and incidence of bone cement leakage were recorded and compared between the two groups; Cobb angle of the injured vertebrae, VAS score, and ODI were measured before operation, at 2 days and 1 year after operation. The contralateral distribution ratio of bone cement was calculated according to the anteroposterior X-ray film at 2 days after operation. RESULTS: The operation time and the intraoperative fluoroscopy times in group A were significantly less than those in group B ( P<0.05). There was no bone cement adverse reactions, cardiac and cerebrovascular adverse events, and no complications such as puncture needles erroneously inserted into the spinal canal and nerve injuries occurred in the two groups. Bone cement leakage occurred in 6 cases and 8 cases in groups A and B, respectively, all of which were asymptomatic paravertebral or intervertebral leakage, and no intraspinal leakage occurred; the bone cement injection amount and incidence of bone cement leakage between the two groups showed no significant differences ( P>0.05). The contralateral distribution ratio of bone cement in group A was significantly lower than that in group B ( t=2.685, P=0.009). Patients in both groups were followed up 12-20 months, with an average of 15.3 months. The Cobb angle of the injured vertebrae, VAS score, and ODI in the two groups were significantly improved at 2 days after operation, however, the Cobb angle of the injured vertebra at 1 year after operation was significantly lost when compared with the 2 days after operation, the VAS score and ODI at 1 year after operation were significantly further improved when compared with the 2 days after operation, the differences were all significant ( P<0.05). There was no significant difference in the Cobb angle of the injured vertebrae, VAS score, and ODI between the two groups at each time point after operation ( P>0.05). CONCLUSION: Bilateral percutaneous balloon kyphoplasty through unilateral transverse process-extrapedicular approach is comparable to bilateral PKP in short-term effectiveness with regard to fracture reduction, reduction maintenance, pain relief, and functional improvement. It has great advantages in reducing operation time and radiation exposure, although it is inferior in bone cement distribution.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Cimentos Ósseos , Fraturas por Compressão/cirurgia , Humanos , Fraturas por Osteoporose/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/cirurgia , Resultado do Tratamento
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