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1.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(9): 1047-1055, 2022 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-36111464

RESUMO

Objective: Anterior cruciate ligament (ACL) reconstruction using a new generation of artificial ligaments (NGAL) gained popularity in China owing to its good effectiveness and early functional recovery, but iatrogenic surgical failures and preconceived misconceptions have seriously affected its standardized clinical application. A specialist consensus is now developed to provide guidance and reference for orthopaedic sports medicine doctors when adopting or considering the NGAL for ACL reconstruction. Methods: The consensus on the core techniques and adverse events in ACL reconstruction using the NGAL was developed by a modified Delphi method, referring exclusively to the NGAL for ACL reconstruction approved by the National Medical Products Administration (NMPA). Consensus specialists were selected from the members of the Chinese Association of Orthopaedic Surgeons (CAOS) and the Chinese Society of Sports Medicine (CSSM). The drafting team summarized the draft consensus terms based on medical evidence and organized rounds of investigation: two rounds of online questionnaire investigation and the final round of face-to-face meeting. After discussion, revision, and voting, a consensus on the draft consensus term was reached when the agreement rate exceeded 85%. The consensus terms were categorized as "strong" (agreement rate: 95.0%-100%), "moderate" (agreement rate: 90.0%-94.9%), and "basic" (agreement rate: 85.0%-89.9%). Results: Thirty-one specialists completed the questionnaire investigation. They all practiced in university teaching hospitals (Grade-A tertiary hospitals) from 16 provinces, autonomous regions, and municipalities in China. Among them, 28 were chief physicians and 3 were associate chief physicians; 22 were professors and 7 were associate professors; the average seniority in orthopedic sports medicine was 25.2 years (range, 12-40 years); the average seniority in performing ACL reconstruction procedures was 13.2 years (range, 7-23 years); in terms of the number of ACL reconstruction using the NGAL, 18 completed more than 100 cases, of which 6 had more than 300 cases; in terms of research, 28 had published more than 1 related paper in the past 5 years, of which 13 had published more than 3 related papers. Twenty-six specialists attended the face-to-face meeting and reached a consensus on 9 terms, including 8 strong terms and 1 moderate term. Conclusion: ACL reconstruction using the NGAL must deploy "isometric" or "near-isometric" reconstruction and should preserve the natural ACL remnants as much as possible. Bone tunnel positioning can be performed using intraoperative radiographic measurements or the lateral femoral intercondylar ridge as reference marks. Incorrect positioning of the bone tunnel is the main reason of surgical failure, and there is a lack of consensus on handling interference screws during revision. Bone tunnel enlargement exists after reconstruction but rarely causes related symptoms. Synovitis and infection are uncommon complications. The aging effect of polyethylene terephthalate fiber on the long-term clinical outcomes is unknown and deserves attention.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Polietilenotereftalatos , Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Consenso , Técnica Delfos , Humanos , Lipocalina-2
2.
Water Res ; 223: 119038, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36067605

RESUMO

Microplastics are ubiquitous in estuaries, coasts, sewage and wastewater treatment plants (WWTPs), which could arouse unexpected effects on critical microbial processes in wastewater treatment. In this study, polyethylene terephthalate microplastics (PET-MPs) were selected to investigate the mechanism of its influence on the performance of sulfur-mediated biological process from the perspective of microbial metabolic activity, electron transfer capacity and microbial community. The results indicated that the exposure of 50 particles/L PET-MPs improved the chemical oxygen demand (COD) and sulfate removal efficiencies by 6.6 ± 0.5% and 4.5 ± 0.3%, respectively, due to the stimulation of microbial metabolic activity and the enrichment of sulfate-reducing bacteria (SRB) species, such as Desulfobacter. In addition, we found that the PET-MPs promoted Cytochrome C (Cyt C) production and improved the direct electron transfer (DET) capacity mediated by Cyt C. The long-term presence of PET-MPs stimulated the secretion of extracellular polymeric substance (EPS), especially the proteins and humic substances, which have been verified to be electroactive polymers to act as electron shuttles to promote the interspecies electron transfer pathway in sulfur-mediated biological process. Meanwhile, the transformation products (bis-(2-hydroxyethyl) terephthalate (BHET) and Mono (2-hydroxyethyl) terephthalic acid (MHET) of PET-MPs were detected in sulfur-mediated biological process. These findings indicate that the sulfur-mediated biological process has good adaptability to the toxicity of PET-MPs, which strengthens a deeper understanding of the dual function of microplastics in WWTPs.


Assuntos
Microbiota , Poluentes Químicos da Água , Citocromos c , DEET , Elétrons , Matriz Extracelular de Substâncias Poliméricas , Substâncias Húmicas , Microplásticos , Plásticos , Polietileno , Polietilenotereftalatos , Esgotos , Sulfatos , Enxofre
3.
J Mech Behav Biomed Mater ; 134: 105391, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35930946

RESUMO

OBJECTIVES: The aim was to investigate the full-field mechanical-deformation behavior of clear aligners made by polyethylene terephthalate glycol (PET-G) subjected to cyclic compression tests. METHODS: Digital Image Correlation (DIC) (Chu et al., 1985; Schreier et al., 2009), a contactless full-field measurement technique, and Optical Microscope (OM) analysis were applied to study two PET-G aligners thermoformed from discs of a thickness of 0.75 mm and 0.88 mm. The clear aligners were placed on dental shape resin casts and were subjected to cyclic compression up to 13000 load cycles from 0 to 50 N at room temperature. The chosen number of load cycles simulates the average load history to which an aligner is subjected for one week. Local displacements and strains were measured for each test at 2, 6, 10, 20, 1000, 5000 and 13000 loading cycles. RESULTS: Both aligners showed greater displacements in the early stages of loading, more pronounced for the 0.88 mm one. Local displacement and strain maps are derived both along the load direction and to the transverse one (never done from other researchers). Load-displacement cyclic curves allowed to evaluate the evolution of the stored energy and the stiffness during the test. The OM analyses showed significant morphological variations on the aligners' surface, such as wear and tear, high depressions and cracks, especially for the 0.75 mm specimen. SIGNIFICANCE: Full-field analysis allowed to understand the mechanical behavior of device with complex geometry and complex load distribution, like invisible aligners. The knowledge of the stiffness and the direction of the total displacement helps the orthodontist to implement the best strategy to improve the patient's comfort and the treatment time.


Assuntos
Desenho de Aparelho Ortodôntico , Polietilenoglicóis , Dacarbazina , Humanos , Polietilenotereftalatos
4.
Anal Chem ; 94(35): 12078-12085, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35998416

RESUMO

The increasing accessibility of 3D printers makes their use for criminal activity more likely. Current forensic analysis of trace evidence left by 3D-printed materials focuses on identifying the general type of plastic, which includes acrylonitrile butadiene styrene, polylactic acid, nylon, polycarbonate, polyethylene terephthalate, and chlorinated polyethylene. Herein, we present a nondestructive approach capable of differentiating among different types of nylons. The new approach is based on room-temperature fluorescence spectroscopy. Excitation-emission matrices, excitation and emission spectra, and synchronous fluorescence spectra are directly recorded from single microplastics with the aid of a fiber-optic probe coupled to a commercial spectrofluorometer. The comparison of spectral features demonstrates the capability to differentiate microparticles originating from Nylon 11, Nylon 12, Nylon 6/6, and Nylon 6/12. The observed differences are attributed to the presence of fluorescent impurities embedded in the polymer during its fabrication. The outstanding matching of excitation-emission matrices, excitation and emission spectra, and synchronous fluorescence spectra demonstrates the potential of this approach to link trace evidence to a specific source beyond its general plastic type.


Assuntos
Nylons , Plásticos , Nylons/química , Polietilenotereftalatos , Espectrometria de Fluorescência/métodos , Temperatura
5.
Sci Rep ; 12(1): 13573, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945452

RESUMO

In times of collective concern about pandemics, body-shield resuscitation barrier devices are more and more considered to protect against transmission of different pathogens between rescuers and patients. The objective of this experimental study was to investigate the characteristics of blood drops dispersed on the surface of four different foils suitable for blanketing patients during resuscitation. We analyzed run-off characteristics of blood stains depending on surface properties of polyvinyl chloride, polyethylene, polyethylene terephthalate and aluminum-coated polyethylene terephthalate. Confocal fluorescence microscopy revealed less cellular density and lack of fibrin networks in blood stains on the four foil surfaces than on paper towel. Delayed clotting went along with larger areas of contamination indicating a greater likelihood of coming into contact with potential germs but a smaller chance of contracting an infection. Space blankets as obligatory components of first aid kits are readily available for rescuers and serve as a mechanical barrier between rescuers and patients during resuscitation.


Assuntos
Polietilenotereftalatos , Equipamentos de Proteção , Humanos , Polietileno , Ressuscitação , Propriedades de Superfície
6.
Anal Chim Acta ; 1225: 340256, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36038246

RESUMO

Ammonia (NH3) has been used as a typical indicator to monitor food spoilage, human health, and air quality. However, the development of flexible NH3 sensors with high response, excellent selectivity and low cost remains a huge challenge. Herein, a high performance NH3 sensor based on Ti3C2Tx MXene nanosheet/urchin-like PANI hollow nanosphere composite (MP) was fabricated through template method and in situ polymerization. The NH3 sensor is fabricated with no high cost electrodes through directly depositing this composite on flexible polyethylene terephthalate (PET) during polymerization. This optimized MP film sensor exhibits high response of 3.70 to 10 ppm NH3 at room temperature, which is 4.74-fold in comparison with urchin-like PANI hollow nanosphere (u-PANI). It also shows excellent selectivity, good repeatability, satisfactory flexibility, air stability and low detection limit of 30 ppb. The effective morphology control and heterojunction construction of MP composite are responsible for superior sensing performance. Moreover, the application of this film sensor in the monitoring of the spoilage process of fresh pork is demonstrated. This study offers a new strategy for fabricating high performance flexible room-temperature NH3 sensors, which may be scale fabrication and application in daily life.


Assuntos
Amônia , Nanosferas , Carbono , Gases , Humanos , Polietilenotereftalatos , Polimerização , Titânio
7.
Environ Pollut ; 310: 119895, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35961571

RESUMO

This paper investigated the impacts of various real microplastics (MPs), i.e., polyethylene (PE) and polyethylene terephthalate (PET) with different sizes (1000-2000 and 100-200 µm) and different dosages (0.5 and 5% on a dry weight basis), on the toluene removal during the thermally enhanced air injection treatment. First, microscopic tests were carried out to determine the MPs' microstructure and behavior. The PE was mainly a small block, and PET appeared filamentous and sheeted with a larger slenderness ratio. Second, the interactions between MPs and toluene-contaminated soils were revealed by batch adsorption equilibrium experiments and low-field magnetic resonance. The morphological differences and dosage of the MPs impacted soils' total porosity (variation range: 39.2-42.7%) and proportion of the main pores (2-200 µm). Third, the toluene removal during the air injection consisted of compaction, rapid growth, rapid reduction, and tailing stages, and the MPs were regarded as an emerging solid state to affect these removal stages. The final cumulative toluene concentrations of soil-PET mixtures were influenced by total porosity, and those of soil-PE mixtures were controlled by total porosity (influence weight: 0.67) and adsorption capacity (influence weight: 0.33); meanwhile, a self-built comprehensive coefficient of MPs can reflect the relationship between them and cumulative concentrations (correlation coefficient: 0.783).


Assuntos
Microplásticos , Poluentes do Solo , Plásticos , Polietileno , Polietilenotereftalatos , Solo , Tolueno
8.
Water Res ; 223: 118992, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36007402

RESUMO

The release of microplastics from sewage treatment works (STWs) into the oceans around coastal cities is well documented. However, there are fewer studies on the microplastic abundance in stormwater drains and their emissions into the coastal marine environment via sewage and stormwater drainage networks. Here, we comprehensively investigated microplastic abundance in 66 sewage and 18 sludge samples collected from different process stages at three typical STWs and 36 water samples taken from six major stormwater drains during the dry and wet seasons in Hong Kong, which is a metropolitan city in south China. The results showed that microplastics were detected in all the sewage and stormwater samples, with the abundance ranging from 0.07 to 91.9 and from 0.4 to 36.48 particles/L, respectively, and in all the sludge samples with the abundance ranging from 167 to 936 particles/g (d. w.). There were no significant seasonal variations in the microplastic abundance across all samples of sewage, sludge, and stormwater. For both waterborne sample types, a smaller size (0.02-0.3 mm) and fiber shape were the dominant characteristics of the microplastics. Polyethylene terephthalate (PET) and polypropylene (PP) were the most abundant polymer types in the sewage samples, while polyethylene (PE), PET, PP, and PE-PP copolymer were the most abundant polymer types in the stormwater samples. The estimated range of total daily microplastic loads in the effluent from STWs in Hong Kong is estimated to be 4.48 × 109 - 2.68 × 1010 particles/day, demonstrating that STWs are major pathways of microplastics in coastal environments despite the high removal percentage of microplastics in sewage treatment processes examined. This is the first comprehensive study on microplastics in the urban waters of a coastal metropolis. However, further studies on other coastal cities will enable an accurate estimation of the microplastic contribution of stormwater drains to the world's oceans.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Plásticos , Polietileno/análise , Polietilenotereftalatos , Polipropilenos/análise , Esgotos , Água , Poluentes Químicos da Água/análise
9.
Food Chem ; 397: 133758, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940101

RESUMO

Head space (HS)-GC-MS was used to analyze possible migration of volatile compounds from polyethylene terephthalate (PET) bottles for soft drinks, and a total of six compounds were identified. Next, a rapid, simple, and accurate simultaneous method was established using purge-and-trap (PT)-GC-MS, to quantify their amounts in the liquid contents after short- and long-term storage in PET bottles. Starting with brand-new PET bottles, the maximum migration of 2-methyl-1,3-dioxolane into distilled water and 50 % aqueous ethanol after 2 years at 25 °C were 2.3 and 19 ng/mL, respectively. In commercially available bottled mineral water sold inside and outside Japan, we were able to detect 2-methyl-1,3-dioxolane in the same way. While nonanal was also detected in some products, 2-methyl-1,3-dioxolane was confirmed as the main volatile compound. Finally, the human exposure to 2-methyl-1,3-dioxolane was estimated based on the per capita intake of soft drinks in Japan and the migration amount in this study.


Assuntos
Água Potável , Polietilenotereftalatos , Bebidas Gaseificadas , Alimentos , Contaminação de Alimentos/análise , Embalagem de Alimentos , Humanos
10.
Biochem Biophys Res Commun ; 626: 100-106, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-35981419

RESUMO

Polyethylene terephthalate (PET) is one of the most abundantly produced synthetic polyesters. The vast number of waste plastics including PET has challenged the waste management sector while also posing a serious threat to the environment due to improper littering. Recently, enzymatic PET degradation has been shown to be a viable option for a circular plastic economy, which can mitigate the plastic pollution. While protein engineering studies on specific PET degradation enzymes such as leaf-branch compost cutinase (LCC), Thermobifida sp. cutinases and Ideonella sakaiensis PETase (IsPETase) have been extensively published, other homologous PET degrading enzymes have received less attention. Ple629 is a polyester hydrolase identified from marine microbial consortium having activity on PET and the bioplastic polybutylene adipate terephthalate (PBAT). In order to explore its catalytic mechanism and improve its potential for PET hydrolysis, we solved its crystal structure in complex with a PET monomer analogue, and validated its structural and mechanistic similarity to known PET hydrolases. By structural comparisons, we identified some hot spot positions described in previous research on protein engineering of PET hydrolases. We substitute these amino acid residues in Ple629, and obtained variants with improved activity and thermo-stability. The most promising variant D226A/S279A exhibited a more than 5.5-fold improved activity on PET nanoparticles than the wild-type enzyme, suggesting its potential applicability in the biotechnological plastic recycling.


Assuntos
Hidrolases , Plásticos , Hidrolases/metabolismo , Hidrólise , Plásticos/química , Polietilenotereftalatos/metabolismo , Engenharia de Proteínas
11.
J Hazard Mater ; 440: 129803, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36027743

RESUMO

In the field of microplastics research, more accurate standardised methods and analytical techniques still need to be explored. In this study, a new method for the microplastics quantitatively and qualitatively analysis by two-phase (ethyl acetate-water) system combined with confocal Raman spectroscopy was developed. Microplastics can be separated from false-positive microplastics in beach sand and marine sediment, attributing to the hydrophobic-lipophilic interaction (HLI) of the two-phase system. Results show that the recovery rates of complex environment microplastics (polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyamide 66 (PA 66), polycarbonate (PC) and polyethylene (PE)) are higher than 92.98%. Moreover, the new technique can also be used to detect hydrophobic and lipophilic antibiotics, such as sulfamethoxazole (SMX), erythromycin (EM), madimycin (MD), and josamycin (JOS), which adsorbed on microplastics and are extracted based on the dissolving-precipitating mechanism. This innovative research strategy provides a new scope for further detection of marine environment microplastics and toxic compounds adsorbed on its surface.


Assuntos
Microplásticos , Poluentes Químicos da Água , Antibacterianos/análise , Monitoramento Ambiental/métodos , Eritromicina , Josamicina , Nigéria , Nylons , Plásticos/análise , Polietileno/química , Polietilenotereftalatos , Polipropilenos/química , Cloreto de Polivinila , Areia , Análise Espectral Raman , Sulfametoxazol , Água/análise , Poluentes Químicos da Água/química
12.
J Hazard Mater ; 440: 129771, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36027748

RESUMO

This work comparatively studied the different stress responses of anaerobic hydrogen-producing granular sludge (HPG) to several typical MPs in wastewater, i.e., polyethylene (PE), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) MPs. A new approach to mitigating the inhibition caused by MPs based on biochar was then proposed. The results displayed that microbe in HPG had diverse tolerances to PE-MPs, PET-MPs and PVC-MPs, with the hydrogen production downgraded to 82.0 ± 3.2 %, 72.3 ± 2.5 % and 66.6 ± 2.3 % (p < 0.05) of control respectively, due to the distinct leachates toxicities and oxidative stress level induced by different MPs. The discrepant mitigation reflected in the hydrogen yields of biochar-based HPGs raised back to 88.7 ± 1.4 %, 85.3 ± 3.8 % and 88.5 ± 3.5 % of control. The MPs induced disintegrated granule morphology, fragile microbial viability and impaired defensive function of extracellular polymeric substances were restored by biochar. The effective mitigation was revealed to be due to the strong adsorption of MPs by biochar, reducing direct contact between microbes and MPs. Biochar addition also enhanced protection for HPG by increasing EPS secretion and weakened the oxidative damage to anaerobes induced by MPs. Biochar manifested the disparate adsorption properties of three MPs. The most superior mitigation in HPG contaminated by PVC-MPs was attributed to the strongest affinity of biochar to PVC-MPs and effective alleviation of PVC leachates toxicity.


Assuntos
Microplásticos , Esgotos , Anaerobiose , Carvão Vegetal , Hidrogênio , Microplásticos/toxicidade , Plásticos , Polietileno , Polietilenotereftalatos , Cloreto de Polivinila , Águas Residuárias
13.
Sci Total Environ ; 848: 157722, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35914603

RESUMO

Microplastics in the human diet have become a worldwide concern. To date, microplastics in urban drinking water supplies, such as decentralized drinking-water refill kiosks, have not been studied and are a pressing concern since they are so closely tied to human life and have a significant influence on health. This study evaluated the occurrence and characteristics of microplastics in 63 drinking water samples collected from decentralized refill kiosks in the Mexico City metropolitan area. All of the sampled drinking water contained microplastics in concentrations ranging from 11 to 860 microplastics L-1. The detected microplastics were mostly fiber (65 %), followed by fragment (28 %), and film (7 %). They were mainly composed of polyethylene terephthalate, polyamides, vinyl polymers, polyacetal, and cellophane in sizes ranging from 20 µm to 5 mm, with 75 % of them accounting for sizes <300 µm. SEM-EDX analysis revealed weathered microplastics, biota adherence, and the presence of inorganic elements on the surface of microplastics. We estimate that Mexico City residents inadvertently ingest 42 microplastics L-1, with an annual exposure of around 1.47 × 104 microplastics per adult and 6.73 × 103 microplastics per child. Therefore, future research is needed to strengthen drinking water refill kiosk guidelines and standards for better microplastic management. This study serves as a wake-up call to many developing countries that use similar urban water systems, drawing their attention to global microplastic contamination of drinking water.


Assuntos
Água Potável , Poluentes Químicos da Água , Celofane , Criança , Água Potável/análise , Monitoramento Ambiental , Humanos , Microplásticos , Nylons , Plásticos/análise , Polietilenotereftalatos , Polímeros , Poluentes Químicos da Água/análise
14.
Sci Total Environ ; 846: 157358, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35850328

RESUMO

There has been a growing interest in poly(ethylene terephthalate) PET degradation studies in the last few years due to its widespread use and large-scale plastic waste accumulation in the environment. One of the most promising enzymatic methods in the context of PET degradation is the use of PETase from Ideonella sakaiensis, which has been reported to be an efficient enzyme for hydrolysing ester bonds in PET. In our study, we expressed a codon-optimized PETase gene in the yeast Yarrowia lipolytica. The obtained strain was tested for its ability to degrade PET directly in culture, and a screening of different supplements that might raise the level of PET hydrolysis was performed. We also carried out long-term cultures with PET film, the surface of which was examined by scanning electron microscopy. The efficiency of PET degradation was tested based on the concentration of degradation products released, and the results showed that supplementation of the culture with olive oil resulted in 66 % higher release of terephthalic acid into the medium compared to the mutant culture without supplementation. The results indicate the possibility of ethylene glycol uptake by both strains, and, additionally, the PETase produced by the newly engineered strain hydrolyses MHET. The structure of the PET film after culture with the modified strain, meanwhile, had numerous surface defects, cracks, and deformations.


Assuntos
Polietilenotereftalatos , Yarrowia , Etilenos , Hidrolases/química , Hidrolases/genética , Hidrolases/metabolismo , Ácidos Ftálicos , Polietilenotereftalatos/química , Yarrowia/genética
15.
Int J Mol Sci ; 23(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35806443

RESUMO

Surface coatings of materials by polysaccharide polymers are an acknowledged strategy to modulate interfacial biocompatibility. Polysaccharides from various algal species represent an attractive source of structurally diverse compounds that have found application in the biomedical field. Furcellaran obtained from the red algae Furcellaria lumbricalis is a potential candidate for biomedical applications due to its gelation properties and mechanical strength. In the present study, immobilization of furcellaran onto polyethylene terephthalate surfaces by a multistep approach was studied. In this approach, N-allylmethylamine was grafted onto a functionalized polyethylene terephthalate (PET) surface via air plasma treatment. Furcellaran, as a bioactive agent, was anchored on such substrates. Surface characteristics were measured by means of contact angle measurements, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Subsequently, samples were subjected to selected cell interaction assays, such as antibacterial activity, anticoagulant activity, fibroblasts and stem cell cytocompatibility, to investigate the Furcellaran potential in biomedical applications. Based on these results, furcellaran-coated PET films showed significantly improved embryonic stem cell (ESC) proliferation compared to the initial untreated material.


Assuntos
Alginatos , Polietilenotereftalatos , Antibacterianos/farmacologia , Gomas Vegetais , Polietilenotereftalatos/química , Polímeros/química , Propriedades de Superfície
16.
BMC Musculoskelet Disord ; 23(1): 648, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794545

RESUMO

BACKGROUND: Acromioclavicular (AC) joint dislocation is common among shoulder injuries, and various surgical methods have been introduced for effective ligament reconstruction. Reconstruction of the coracoclavicular (CC) ligament in the anatomical position using autologous tendons is a recent surgical trend. This study is to report clinical and radiologic results of reconstruction of the CC ligament using an autologous palmaris longus tendon interweaved with Mersilene tape (PLMT) with a minimum 2-year follow-up. METHODS: This retrospective study analyzed 76 patients (mean age, 43.4 ± 11.2 years) with AC joint dislocation treated by reconstruction of the CC ligament with PLMT, from March 2004 to February 2017. The mean follow-up period was 28 ± 6.7 months (range, 24-66 months). The Visual Analog Scale (VAS) for pain assessment, American Shoulder and Elbow Surgeons rating scale (ASES), and Constant Score (CS) were used to evaluate clinical outcomes at the preoperative and the final follow-ups. CC and AC distances were measured using anteroposterior (AP) X-ray preoperatively and at the final follow-up for radiologic outcomes. Complications were also assessed. RESULTS: The mean preoperative VAS for pain, ASES, CS were 5.7 ± 0.7, 77.1 ± 6.2, and 61.5 ± 5.2, respectively. These scores at the final follow-up improved to 2.1 ± 0.5, 90.9 ± 4.3, and 94 ± 7.0, respectively (p = 0.043, p <  0.001, p <  0.001). The mean preoperative CC and AC distances were 16.49 ± 3.73 mm and 13.84 ± 3.98 mm, respectively. The final follow-up CC and AC distances were 9.29 ± 2.72 mm and 5.30 ± 2.09 mm, respectively (p <  0.001, p <  0.001). Although a slight re-widening of the CC distance occurred in 10 patients (13.1%), most patients regained full range of motion of the affected shoulder at the final follow-up. CONCLUSION: The CC ligament reconstruction with PLMT for the treatment of AC joint dislocation showed good clinical and radiological results. This technique could be a good alternative treatment for AC dislocations.


Assuntos
Luxações Articulares , Luxação do Ombro , Adulto , Humanos , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/cirurgia , Pessoa de Meia-Idade , Polietilenotereftalatos , Estudos Retrospectivos , Luxação do Ombro/cirurgia , Tendões
17.
Artigo em Inglês | MEDLINE | ID: mdl-35822641

RESUMO

We present a case of late mediastinitis following surgery for type A aortic dissection. After a thorough preoperative workup, the patient underwent a redo sternotomy, removal of all prosthetic material, and replacement of the aortic root with a homograft. The patient required venoarterial extracorporeal membrane oxygenation and delayed sternal closure for post-postoperative biventricular failure as well as prolonged antibiotic treatment. We present our institutional multidisciplinary approach for the management of such complex cases.


Assuntos
Aneurisma Dissecante , Próteses Valvulares Cardíacas , Mediastinite , Aneurisma Dissecante/cirurgia , Aorta/cirurgia , Humanos , Mediastinite/etiologia , Mediastinite/cirurgia , Polietilenotereftalatos
18.
Carbohydr Polym ; 294: 119804, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868764

RESUMO

Using sustainable cellulose and its derivatives to prepare optical diffuser is an economic and green approach. Herein, we report a novel optical diffuser constructed by interfacial assembly of cellulose ether (CE) and polymer complex particles (PCP) on flexible and transparent poly(ethylene terephthalate) (PET) substrate. Owning to the rich hydroxyl groups of CEs, the complex thin film can be further crosslinked by thermal treatment which greatly improves the optical diffusion performance and durability. Without crosslinking, haze (H) of the cellulose complex film is about 81 %, and the film will dissolve in high pH value solution. While after the proper crosslinking, H of the film increases to 95 %, and the film can resist the erosion of high pH solution. Moreover, CE/PCP complex film shows improved anti-bending capacity compared with commercially available optical diffuser for liquid crystal display.


Assuntos
Celulose , Polímeros , Celulose/química , Éter , Éteres , Polietilenotereftalatos/química
19.
PLoS One ; 17(7): e0269664, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830388

RESUMO

In recent decades, several studies have considered the use of plastic waste as a partial substitute for aggregate in green concrete. Such concrete has been limited to non-structural applications due to its low strength. This raises whether such concrete can be enhanced for use in some structural applications. This paper reports an attempt to develop a structural-grade concrete containing plastic waste aggregate with high proportions of substitution and confined with carbon fiber reinforced polymer (CFRP) fabrics. Experimental research was conducted involving the casting and testing 54 plain and confined concrete cylinders. A concrete mixture was designed in which the fine aggregate was partially replaced by polyethylene terephthalate (PET) waste plastic at ratios of 0%, 25%, and 50%, and with different w/c ratios of 0.40, 0.45, and 0.55. The results show that confinement has a substantial positive effect on the compressive behavior of PET concrete. The enhancement efficiency increases by 8-190%, with higher enhancement levels for higher substitution ratios. Adding one layer of CFRP fabric raises the ultimate strength of samples that have lost compressive strength to a level close to that of unconfined samples not containing PET. This confinement is accompanied by an increase in the slope of the stress-strain curve and greater axial and lateral strain values at failure. For the specimens confined by CFRP fabric, PET aggregate can be used as a partial substitute for sand at a replacement ratio of up to 50% by volume for structural applications. This paper also considers the ability of existing models to predict the strength of confined-PET concrete circular cross-sections by comparing model predictions with experimental results. The strength of confined PET concrete elements can't be accurately predicted by any of the models that are already out there. It's important to come up with a new model for these elements.


Assuntos
Materiais de Construção , Polietilenotereftalatos , Fibra de Carbono , Plásticos , Polímeros
20.
Environ Sci Technol ; 56(15): 10732-10742, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35816335

RESUMO

Adverse effects of microplastics on soil abiotic properties have been attributed to changes in the soil structure. Notably, however, the effects on the supramolecular structure of soil organic matter (SOM) have been overlooked, despite their key role in most soil properties. This work accordingly investigated the influence of plastic residues at various concentrations on the SOM supramolecular structure and soil water properties. To model plastic residues of micro-bioplastics, spherical or spherical-like poly-3-hydroxybutyrate (PHB) was used, while polyethylene terephthalate (PET) was used as a model of conventional microplastics. The results suggest that both types of plastic residues affect SOM properties, including physical stability (represented by water molecule bridges), water binding (represented by decreased desorption enthalpy or faster desorption), and the stability of SOM aliphatic crystallites. The results further showed that the polyester-based microplastics and micro-bioplastics affected the SOM abiotic characteristics and that therefore the observed effects cannot be attributed solely to changes in the whole soil structure. Notably, similar adverse effects on SOM were observed for both tested plastic residues, although the effect of PHB was less pronounced compared to that of PET.


Assuntos
Microplásticos , Solo , Hidroxibutiratos , Plásticos , Poliésteres , Polietilenotereftalatos , Solo/química , Água
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