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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121779, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36041262

RESUMO

Online monitoring of antibiotics in the environment attracts more and more attention. Surface-enhanced Raman scattering (SERS) is a promising technique for the detection of trace amounts of antibiotics in the environment, which is fast, non-invasive and sensitive. To investigate the enrichment of trace amounts of antibiotics in water, polyethylene microplastics (PE MPs) were prepared as sorbents to simply concentrate enrofloxacin, ciprofloxacin hydrochloride monohydrate and triclosan in water, followed by the SERS measurement of antibiotics extract washed from MPs on an AgNPs@Si SERS substrate. Limit of detection of Rhodamine 6G is 2.1 × 10-12 M achieved from the AgNPs@Si SERS, indicating a high enhancement. The detection results show that SERS peaks of the antibiotics could be observed from the spectra of the extracts eluted from MPs, indicating MPs could adsorb and desorb antibiotics from water. Besides, for enrofloxacin and triclosan, the intensity of SERS measured from the MPs extracts are higher than that of directly from the spiked water, demonstrating the proposed method could lower the detectable concentration of hydrophobic antibiotics in water. Moreover, the proposed MPs sorbents combined with SERS method was applied to detect the antibiotics in real river water, with minimal detection of 10-10 M, 10-8 M, and 10-8 M achieved for enrofloxacin, ciprofloxacin hydrochloride monohydrate and triclosan, respectively. The proposed method provides a promising simple, rapid and low reagent consuming means for monitoring antibiotics in water.


Assuntos
Antibacterianos , Triclosan , Antibacterianos/análise , Ciprofloxacina , Enrofloxacina , Microplásticos , Plásticos , Polietilenos , Prata/química , Análise Espectral Raman/métodos , Tecnologia , Água
2.
J Biomed Mater Res B Appl Biomater ; 111(1): 26-37, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35809250

RESUMO

Vitamin E (VE) is currently an approved antioxidant to improve the oxidation stability of highly crosslinked ultrahigh molecular weight polyethylene (UHMWPE) insert used commercially in total joint arthroplasty. However, the decrease in crosslink density caused by VE reduces wear resistance of UHMWPE, showing an uncoordinated challenge. In this work, we hypothesized that D-sorbitol (DS) as a secondary antioxidant can improve the antioxidant efficacy of VE on chemically crosslinked UHMWPE. The combined effect of VE and DS on oxidation stability of UHMWPE was investigated at a set of controlled hybrid antioxidant content. The hybrid antioxidant strategy showed significantly synergistic enhancement on the oxidation stability of chemically crosslinked UHMWPE compared with the single VE strategy. More strikingly, the crosslink density of the blends with hybrid antioxidants stayed at a high level since DS is not sensitive to crosslinking. The relationships between oxidation stability, mechanical properties, crosslink density, and crystallinity were investigated, by which the clinically relevant overall performance of UHMWPE was optimized. This work provides a leading-edge design mean for the development of joint bearings.


Assuntos
Antioxidantes , Polietilenos , Antioxidantes/química , Peso Molecular , Teste de Materiais , Polietilenos/química , Vitamina E/química
3.
Nat Commun ; 13(1): 7187, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418305

RESUMO

Polyolefins comprise a major fraction of single-use plastics, yet their catalytic deconstruction/recycling has proven challenging due to their inert saturated hydrocarbon connectivities. Here a very electrophilic, formally cationic earth-abundant single-site organozirconium catalyst chemisorbed on a highly Brønsted acidic sulfated alumina support and characterized by a broad array of experimental and theoretical techniques, is shown to mediate the rapid hydrogenolytic cleavage of molecular and macromolecular saturated hydrocarbons under mild conditions, with catalytic onset as low as 90 °C/0.5 atm H2 with 0.02 mol% catalyst loading. For polyethylene, quantitative hydrogenolysis to light hydrocarbons proceeds within 48 min with an activity of > 4000 mol(CH2 units)·mol(Zr)-1·h-1 at 200 °C/2 atm H2 pressure. Under similar solventless conditions, polyethylene-co-1-octene, isotactic polypropylene, and a post-consumer food container cap are rapidly hydrogenolyzed to low molecular mass hydrocarbons. Regarding mechanism, theory and experiment identify a turnover-limiting C-C scission pathway involving ß-alkyl transfer rather than the more common σ-bond metathesis.


Assuntos
Plásticos , Zircônio , Zircônio/química , Cátions , Hidrocarbonetos/química , Polietilenos
4.
Sensors (Basel) ; 22(20)2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36298199

RESUMO

A fiber optic pressure sensor that can survive 2200 psi and 140 °C was developed. The sensor's pressure sensitivity was measured to be 14 times higher than bare FBG when tested inside stacks of ultra-high-molecular-weight polyethylene (UHMWPE) composite fabric. The sensitivity can be further improved 6-fold through the Vernier effect. Its tiny sensing length (hundreds of microns) and uniform outer diameter (125 µm) make it a suitable candidate for real-time point pressure monitoring under harsh environments with limited space, such as in composite-forming procedures.


Assuntos
Tecnologia de Fibra Óptica , Interferometria , Refratometria , Desenho de Equipamento , Polietilenos
5.
J Adhes Dent ; 24(1): 385-394, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36278397

RESUMO

PURPOSE: To evaluate the effect of universal adhesives on the long-term bond strength to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP). MATERIALS AND METHODS: Polyethylene tubes filled with composite cement containing 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) were adhesively luted to 60 fully sintered Y-TZP slabs (7 x 7 x 2 mm) with or without (control) previous application of a 10-MDP-based adhesive (All Bond Universal, Bisco) - ABU; Clearfil Universal Bond Quick, Kuraray Noritake - CUB; Scotchbond Universal Adhesive, 3M Oral Care - SUA) on the zirconia surface. The bonded specimens were stored in water for 24 h, 6 months, or 1 year and subjected to microshear bond strength testing. The data were analyzed by one-way ANOVA and Tukey's test (p < 0.05). The contact angle was measured after adhesive application to evaluate surface wettability. The adhesive-treated specimens were analyzed with x-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) for chemical characterization. RESULTS: The application of a 10-MDP-based adhesive significantly improved bond strength of composite cement to zirconia when compared to the control group (no adhesive application) (p < 0.05). One-year water storage significantly decreased bond strength for ABU- and CUB-bonded specimens, but not for SUA-bonded specimens. The analysis by XPS and ToF-SIMS showed peaks of carbon, phosphorus, and silicon in all adhesive-treated specimens. CONCLUSIONS: One-year water storage affected the bond strength of composite cement to zirconia when All Bond Universal or Clearfil Universal Bond Quick were used.


Assuntos
Colagem Dentária , Cimentos Dentários , Silício , Teste de Materiais , Propriedades de Superfície , Materiais Dentários/química , Água/química , Carbono , Fósforo , Polietilenos
6.
Cells ; 11(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36291134

RESUMO

As a novel cell type from eight-cell-stage embryos, extended pluripotent stem cells (EPSCs) are known for diverse differentiation potency in both extraembryonic and embryonic lineages, suggesting new possibilities as a developmental research model. Although various features of EPSCs have been defined, their ability to directly transfer extended pluripotency to differentiated somatic cells by cell fusion remains to be elucidated. Here, we derived EPSCs from eight-cell mouse embryos and confirmed their extended pluripotency at the molecular level and extraembryonic differentiation ability. Then, they were fused with OG2+/- ROSA+/- neural stem cells (NSCs) by the polyethylene-glycol (PEG)-mediated method and further analyzed. The resulting fused hybrid cells exhibited pluripotential markers with upregulated EPSC-specific gene expression. Furthermore, the hybrid cells contributed to the extraembryonic and embryonic lineages in vivo and in vitro. RNA sequencing analysis confirmed that the hybrid cells showed distinct global expression patterns resembling EPSCs without parental expression of NSC markers, indicating the complete acquisition of extended pluripotency and the erasure of the somatic memory of NSCs. Furthermore, ultrastructural observation and metabolic analysis confirmed that the hybrid cells rearranged the mitochondrial morphology and bivalent metabolic profile to those of EPSCs. In conclusion, the extended pluripotency of EPSCs could be transferred to somatic cells through fusion-induced reprogramming.


Assuntos
Células-Tronco Pluripotentes , Camundongos , Animais , Fusão Celular , Células-Tronco Pluripotentes/metabolismo , Diferenciação Celular , Polietilenos/metabolismo , Glicóis
7.
Sci Rep ; 12(1): 17111, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224202

RESUMO

Water shortages threaten agricultural sustainability in the semi-arid areas of the Loess Plateau. Judicious mulching management can improve water conservation practices to alleviate this issue while increasing crop productivity. We investigated the effect of straw strip mulching and film mulching on soil water consumption, temperature, growth, grain yield, and economic income of soybean [Glycine max(Linn.) Merr.] from 2017 to 2018 in Qingyang on the semi-arid Loess Plateau in China using four treatments: (a) alternating ridges and furrows with ridges mulched with white polyethylene film (PMP), (b) alternating flat and bare land with only the plat mulched by white polyethylene film (PMF), (c) alternating strips mulched with maize (Zea mays L.) straw (SM), and (d) traditional land planting without mulching (CK). The mulching treatments (PMP, PMF, and SM) increased soil water consumption and soil water use efficiency. The SM, PMF, and PMP treatments had 12.3-12.5, 16.8-22.1, and 23.2-24.2 mm higher soil water consumption (0-120 cm depth) than CK, most of which occurred in the 60-120 cm soil layer. Compared with CK, PMP and PMF significantly increased soil temperature by 1.30-1.31 °C and 0.76-1.00 °C, soybean grain yield by 38.6-39.0 % and 38.8-44.2 %, and water use efficiency (WUE) by 27.7-32.8 % and 30.8-37.5 %, respectively, while SM significantly decreased soil temperature by 0.96-1.15 °C, and increased grain yield by 21.8-25.4 % and WUE by 16.9-21.9 %. PMP and PMF did not significantly change soil water consumption, WUE, or grain yield. The SM treatment increased net income by 501.3-691.7 and 1914.5-2244.9 CNY ha-1 relative to PMP and CK, respectively, but PMF and SM did not significantly differ. Therefore, the SM system could help increase grain yields and economic returns in dryland soybean production, avoiding the adverse effects of the increasingly popular plastic mulching approach.


Assuntos
Soja , Água , Agricultura , China , Grão Comestível/química , Plásticos , Polietilenos , Solo , Água/análise , Zea mays
8.
ACS Nano ; 16(10): 16624-16635, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36240110

RESUMO

The rational utilization and circulation of multiple energy sources is an effective way to address the crises of energy shortages and environmental pollution. Herein, microextrusion compression molding, an industrialized polymer molding technology that combines melt blending and compression molding, is proposed for the mass production of a bioinspired micro/nanostructured polyethylene/poly(ethylene oxide)/graphene (MN-PPG) film. The MN-PPG film exhibits robust shape stability, high storage energy density, and excellent thermal management capability owing to the cocontinuous network formed by poly(ethylene oxide) and the polyethylene matrix. The MN-PPG film has sufficient photothermal property due to the uniformly dispersed graphene nanosheets and the bioinspired surface micro/nanostructures. Interestingly, the MN-PPG film surface exhibits durable superhydrophobicity, acid/alkali resistance, and active deicing performance. Further, a multifunctional energy harvesting and circulation system was established by integrating the MN-PPG film, an LED chip, and a thermoelectric module. The hybrid system produced an open-circuit voltage of 315.4 mV and power output of 2.5 W m-2 under 3 sun irradiation. Furthermore, the afterheat generated by the LED chips at night can be converted into electricity through thermoelectric conversion. The proposed method enables the large-scale fabrication of multifunctional phase change composites for energy harvesting in harsh environments.


Assuntos
Grafite , Nanoestruturas , Grafite/química , Polietilenoglicóis , Óxido de Etileno , Nanoestruturas/química , Polímeros/química , Polietilenos , Álcalis
9.
BMC Surg ; 22(1): 357, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36203147

RESUMO

BACKGROUND: Limb salvage reconstruction for pelvic tumors, especially periacetabular tumors, is challenging. We combined the use of dual mobility bearing and 3D-printed hemipelvic prosthesis to improve function and reduce the probability of complications after hemi-pelvic resection in patients with primary acetabular malignancy. The purpose of this study was to evaluate the efficacy and safety of this combination. METHODS: Between October 2011 and May 2021, 11 patients with malignancies involving the acetabulum received hemipelvic replacement with a 3D-printed prosthesis and dual mobility bearing. Follow-up of postoperative survival, complications, and Musculoskeletal Tumor Society 93 (MSTS-93) lower limb functional scores were carried out. A finite element model of the postoperative pelvis was developed and input into the finite element analysis software. The Von Mises equivalent stress formula was used to analyze the stress distribution of each part of the pelvis under one gait cycle and the stress distribution at different angles of the hip joint. RESULTS: By the last follow-up, 9 of the 11 patients (81.8%) were still alive, and 2 patients had local tumor recurrence. The complications including 1 deep infection and 1 dislocation of the artificial joint. Excluding 1 amputation patient, the average score of the remaining 8 patients at the last follow-up was 21.4/30 (71.3%) on the MSTS-93. In the reconstructed pelvis, stress distributions were concentrated on the junction between hemipelvic prosthesis and screw and iliac bone on the resected side, and between femoral prosthesis stem and femoral bulb, while the stress of polyethylene lining was small. Before impact, the polyethylene lining will rotate at a small angle, about 3°. The inner stress of polyethylene liner is greater than the outer stress in all conditions. The polyethylene liner has no tendency to slide out. CONCLUSION: Pelvic tumor resection and reconstruction using 3D-printed hemipelvic prosthesis combined with dual mobility bearing was an effective treatment for pelvic tumors. Our patients achieved good early postoperative efficacy and functional recovery. The dual mobility bearing is beneficial to prevent dislocation, and the mechanical distribution and wear of the prosthesis are acceptable.


Assuntos
Neoplasias Ósseas , Neoplasias Pélvicas , Acetábulo/cirurgia , Neoplasias Ósseas/cirurgia , Parafusos Ósseos , Análise de Elementos Finitos , Humanos , Neoplasias Pélvicas/cirurgia , Polietilenos , Impressão Tridimensional , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
10.
AAPS PharmSciTech ; 23(7): 276, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36207561

RESUMO

Pinocembrin (PCB) is 5,7-dihydroxyl flavanone and has multiple pharmacological activities, namely, anti-inflammation, anti-osteoporotic, and so on. However, low water solubility and bioavailability have hindered its application. Herein, we aimed to increase its bioavailability through preparation of F127/MPEG-PDLLA polymer micelles (PCB-M). We characterized the micelles through appropriate attributes such as analysis of particle size (PS), polydispersity (PDI), transmission electron microscopic (TEM) image, stability test, and evaluation of in vitro release of drug. After physical characterization, the respective PS, PDI, and entrapment efficiency (EE) of PCB-M were estimated to be 27.63 ± 0.17 nm, 0.055 ± 0.02, and 90.53 ± 0.01%. Fluorescence probe method was employed to measure critical micelle concentration (CMC) of PCB-M, we observed CMC was low, thereby suggesting that PCB-M had good stability. In vitro release analysis indicated that the rate of cumulative PCB release from PCB-M was greater than 90% in each medium compared with free PCB, which was less than 40%, thus pointing to a significantly improved solubility of PCB. In vivo pharmacokinetic results showed that oral biological availability of PCB-M increased 5.3 folds comparable to free PCB. The effects of PCB on osteoblasts and ALP activities were investigated; subsequently, zebrafish osteoporotic model was established with prednisolone to study the anti-osteoporotic effects of PCB and PCB-M. The results showed that PCB improved osteoporosis with PCB-M being more effective than free PCB. Finally, PCB-M can be used as a promising method to improve the solubility of PCB, while the bioavailability and anti-osteoporotic effect of PCB could be improved, thus laying a foundation for clinical use in the future.


Assuntos
Flavanonas , Micelas , Animais , Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Flavanonas/farmacologia , Tamanho da Partícula , Polietilenoglicóis , Polietilenos , Polímeros , Polipropilenos , Prednisolona , Solubilidade , Água , Peixe-Zebra
11.
Environ Pollut ; 313: 120121, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36089144

RESUMO

Microplastic pollution is currently one of the most intensely studied ecological issues. Numerous studies have estimated the distribution and concentration of microplastics in various environments and determine how they affect their inhabitants. Much less effort has been place on assessing the possible effects of microplastics on interactions between organisms, including interspecific competition. Our aim was to test the hypothesis that the presence of microplastics affects the proportion of individuals of coexisting species and the elimination rate of the inferior competitor. The hypothesis was tested in competitive experiments done in the absence and presence of spherical non-biodegradable polystyrene and polyethylene and biodegradable polyhydroxybutyrate in environmentally relevant densities. In each of the experiments, we used three different pairs of closely related planktonic species of the genus Daphnia composed of the superior and inferior competitor: D. pulex and D. magna, D. magna and D. galeata, D. pulex and D. galeata. The results support our hypothesis and demonstrate each microplastic type had a different effect on the density of the competing species. The presence of polystyrene and polyethylene lowered the density of the superior competitor in each of the three pairs, at least partially due to a reduction in the number of gravid females, but not their fecundity. The presence of the polyhydroxybutyrate, in turn, increased the population density of D. magna in the variants with each of the two remaining species. Moreover, the presence of microplastics affected the elimination rate of the inferior competitor, i.e. polystyrene expedited the exclusion of D. magna by D. pulex, and polyhydroxybutyrate hampered the exclusion of D. magna by D. pulex. Our results suggest that long-term exposure to environmentally relevant densities of both non-biodegradable and biodegradable microplastics may affect the relative abundance of co-occurring species in zooplankton communities, and thus the functioning of aquatic ecosystems.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Daphnia , Ecologia , Ecossistema , Plásticos/toxicidade , Polietilenos/farmacologia , Poliestirenos/farmacologia , Poluentes Químicos da Água/análise
12.
Knee ; 38: 193-200, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36095927

RESUMO

BACKGROUND: To determine the ideal fixation technique for an ACL reconstruction with a hamstring graft, multiple studies have been undertaken to define the initial biomechanical properties of tibial fixation. PURPOSE: The aim of this study was to compare the biomechanical properties of tibial fixation methods by creating single or hybrid systems. METHODS: Bovine tibias and forefoot digital extensor tendons were prepared with four different tibial anterior cruciate ligament fixation methods and compared biomechanically. Fixation materials included polyethylene Ultrabraid high-strength sutures, Biosure interference screws (Smith and Nephew, Memphis, TN, USA), staples (Smith and Nephew, Richards Regular Fixation Staples without Spikes, Memphis, TN, USA), and knotless suture anchors (Multifix-S PEEK) (Smith and Nephew, Memphis, TN, USA). Four groups (n = 5 specimens) were established - group I: single fixation with interference screws; group II: single fixation with knotless anchors; group III: hybrid fixation with interference screws and staples; group IV: hybrid fixation with interference screws and knotless anchors. Each specimen underwent evaluations for cyclic displacement, cyclic stiffness, initial loading strength, ultimate failure load, pull-out displacement, and pull-out stiffness. RESULTS: All specimens completed cyclic loading and load-to-failure. The cyclic displacement in group II, which had a single fixation, indicated significantly greater elongation compared with the other groups (P = 0.002). The hybrid systems were more rigid than the single systems in terms of cyclic stiffness, and no statistically significant difference was observed between the hybrid systems (P = 0.461). Group IV was significantly superior in terms of the ultimate failure load (P = 0.004). No statistically significant differences were noted between the groups for pull-out displacement or pull-out stiffness. CONCLUSION: Single fixation with bioscrews as an in-tunnel tibia fixation method was as successful as hybrid systems. Multifix-S PEEK knotless suture anchors, which can be combined with bioscrews, can be a superior fixation alternative due to its flexibility and ultimate failure load values.


Assuntos
Parafusos Ósseos , Tíbia , Animais , Benzofenonas , Fenômenos Biomecânicos , Bovinos , Humanos , Polietilenos , Polímeros , Tíbia/cirurgia
13.
Int J Mol Sci ; 23(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36142868

RESUMO

Although many noble metals are known for their antibacterial properties against the most common pathogens, such as Escherichia coli and Staphylococcus epidermidis, their effect on healthy cells can be toxic. For this reason, the choice of metals that preserve the antibacterial effect while being biocompatible with health cells is very important. This work aims to validate the effect of gold on the biocompatibility of Au/Ag nanowires, as assessed in our previous study. Polyethylene naphthalate (PEN) was treated with a KrF excimer laser to provide specific laser-induced periodic structures. Then, Au was deposited onto the modified PEN via a vacuum evaporation method. Atomic force microscopy and scanning electron microscopy revealed the dependence of the surface morphology on the incidence angle of the laser beam. A resazurin assay cytotoxicity test confirmed safety against healthy human cells and even cell proliferation was observed after 72 h of incubation. We have obtained satisfactory results, demonstrating that monometallic Au nanowires can be applied in biomedical applications and provide the biocompatibility of bimetallic Au/AgNWs.


Assuntos
Nanofios , Antibacterianos/farmacologia , Escherichia coli , Ouro/química , Ouro/farmacologia , Humanos , Lasers , Nanofios/química , Naftalenos , Polietilenos
14.
J Feline Med Surg ; 24(10): e360-e369, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36074899

RESUMO

OBJECTIVES: The aim of our study was to describe a biomechanical testing protocol to reproduce ex vivo craniodorsal hip luxation specific to the feline model, and evaluate the biomechanical properties of an intact hip joint compared with the fixation strength of two different techniques of extra-articular hip stabilisation. METHODS: Eighteen hip joints (femur and hemipelvis) were harvested from nine mature feline cadavers. CT was performed for each hip joint so that a biomechanical base specific to each joint morphotype could be created using computer-aided design. The biomechanical bases were then produced using a three-dimensional printer to secure the hip joints during testing. A total of 34 biomechanical compression tests were performed. Eighteen compression tests were performed in the control group, of which two fractured. The remaining 16 hip joints were then randomly assigned either to group A (hip joints stabilised with an extra-articular ultra-high molecular weight polyethylene (UHMWPE) implant secured by an interference screw [n = 8]) or to group B (hip joints stabilised with a UHMWPE iliofemoral suture [n = 8]). RESULTS: Mean ± SD yield, failure load and linear stiffness in the control group were 616 ± 168 N, 666 ± 158 N and 231 ± 50 N/mm, respectively. The relative fixation strength (% of intact joint) before hip luxation in groups A and B was 43.8% and 34.7%, respectively. No statistical difference was found between groups A and B for yield and failure load. However, the reoccurrence of craniodorsal hip luxation was higher in group B than in group A, in 5/8 and 0/8 tests, respectively. Moreover, in group A, the extra-articular UHMWPE implant induced caudodorsal hip luxation, reported as failure mode in 7/8 cases. CONCLUSIONS AND RELEVANCE: This modified biomechanical protocol for testing craniodorsal hip luxation in a feline model was validated as repeatable and with acceptable variance. The extra-articular UHMWPE implant stabilisation technique proved to be more efficient in avoiding reoccurrence of craniodorsal hip luxation than UHMWPE iliofemoral suture.


Assuntos
Doenças do Gato , Luxações Articulares , Animais , Fenômenos Biomecânicos , Parafusos Ósseos , Cadáver , Gatos , Luxações Articulares/veterinária , Polietilenos , Suturas
15.
Mar Pollut Bull ; 183: 114080, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057156

RESUMO

This study provides an analysis of the current state of microplastic (MP) contamination along the Mediterranean coastline of Israel. Six strategic sites were monitored in this study - each representing a unique coastal environment. We conclude that Tel Aviv and Hadera, both located near stream estuaries, were highly contaminated (18,777 particles/m3) with MP compared to the other locations. The MP detected included both secondary MP and pristine polymeric pellets. In-depth characterization of the MP illustrated a large percentage of both fragmented and film MP morphologies and the most common MP polymers were polyethylene and polypropylene. Further particle analysis showed that MPs were contaminated with biofilm, including microorganisms such as diatoms, as well as metal residues. Through the spatial analysis presented herein we suggest that local rivers are significant contributors to MP contamination along the Mediterranean Sea coastline of Israel and may pose a direct threat to environment and human health.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Humanos , Israel , Plásticos/química , Polietilenos , Polipropilenos , Poluentes Químicos da Água/análise
16.
Mar Pollut Bull ; 183: 114088, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36063667

RESUMO

We assessed microplastics (MPs) contamination in water, sediments, and tissues (gills, digestive tract, and muscle) of two intertidal crab species with different ecological traits and commercial importance (Menippe mercenaria and Callinectes sapidus), from a coastal lagoon in the southeastern Gulf of Mexico. There were significant differences between MP abundances in the abiotic matrices and between crab species. The burrower, sedentary and carnivorous M. mercenaria bioaccumulates 50 % more MPs than the free-swimming, omnivorous C. sapidus. However, no differences were observed between species' tissues. Fragments were the predominant shape in the tissues of both species, with the exception in the digestive tract of M. mercenaria. We identified polyethylene, and polyethylene terephthalate in water samples and Silopren® in sediment. In both crab species, Silopren and polyethylene predominated. Differences in ecological traits resulted in different bioaccumulation patterns in intertidal crabs.


Assuntos
Braquiúros , Poluentes Químicos da Água , Animais , Bioacumulação , Braquiúros/fisiologia , Monitoramento Ambiental , Golfo do México , Microplásticos , Plásticos , Polietilenotereftalatos , Polietilenos , Água , Poluentes Químicos da Água/análise
17.
ACS Appl Mater Interfaces ; 14(37): 42483-42493, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36073910

RESUMO

Microbial adhesion and contamination on shared surfaces can lead to life-threatening infections with serious impacts on public health, economy, and clinical practices. The traditional use of chemical disinfectants for sanitization of surfaces, however, comes with its share of health risks, such as hazardous effects on the eyes, skin, and respiratory tract, carcinogenicity, as well as environmental toxicity. To address this, we have developed a nonleaching quaternary small molecule (QSM)-based sprayable coating which can be fabricated on a wide range of surfaces such as nylon, polyethylene, surgical mask, paper, acrylate, and rubber in a one-step, photocuring technique. This contact-active coating killed pathogenic bacteria and fungi including drug-resistant strains of Staphylococcus aureus and Candida albicans within 15-30 min of contact. QSM coatings withstood multiple washes, highlighting their durability. Interestingly, the coated surfaces exhibited rapid killing of pathogens, leading to the prevention of their transmission upon contact. The coating showed membrane disruption of bacterial cells in fluorescence and electron microscopic investigations. Along with bacteria and fungi, QSM-coated surfaces also showed the complete killing of high loads of influenza (H1N1) and SARS-CoV-2 viruses within 30 min of exposure. To our knowledge, this is the first report of a coating for multipurpose materials applied in high-touch public places, hospital equipment, and clinical consumables, rapidly killing drug-resistant bacteria, fungi, influenza virus, and SARS-CoV-2.


Assuntos
Anti-Infecciosos , COVID-19 , Desinfetantes , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Acrilatos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Bactérias , COVID-19/prevenção & controle , Desinfetantes/farmacologia , Fungos , Humanos , Nylons/farmacologia , Polietilenos/farmacologia , Borracha , SARS-CoV-2
18.
J Mech Behav Biomed Mater ; 135: 105436, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36087516

RESUMO

Ultra-high molecular weight polyethylene (UHMWPE) and CoCr alloy are popular tribo-pair in total knee replacement. Wear in the liner is a major failure reason for knee implant. Therefore, this work focuses on an approach for reducing the wear rate by irradiating the UHMWPE specimens using Ultraviolet (UV) radiation. The powder of UHMWPE was molded into a plate by microwave-assisted compression (MAC) molding. The UV radiations of intensity 0.025 J/cm2 were irradiated on the MAC molded UHMWPE specimens. The wear rate was determined using a pin on the disc wear tribometer using the pre and post-irradiated UHMWPE specimens as a pin and CoCr alloy as the disc. The pre and post-irradiated UHMWPE sliding was done at the load of 40 N for 1500 m under dry conditions. The reduction in the wear rate recorded was 56% after UV irradiation. The surface morphology of the worn specimens was done using scanning electron microscopy (SEM) and the 3D surface mapping technique. The obtained results of wear rate were validated numerically by implementing the contact problem solution in Archard's wear law using user-subroutine on Python. The experimental and numerically obtained results were in good agreement. The biological response of pre and post-irradiated specimens was evaluated by hemolysis assay, cellular compatibility against peripheral blood mononuclear cells, platelet adhesion, and in vitro degradation under a simulated blood fluid environment.


Assuntos
Artroplastia do Joelho , Ligas , Leucócitos Mononucleares , Teste de Materiais , Polietilenos , Pós
19.
Bone Joint J ; 104-B(10): 1132-1141, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36177637

RESUMO

AIMS: To analyze the short-term outcome of two types of total wrist arthroplasty (TWA) in terms of wrist function, migration, and periprosthetic bone behaviour. METHODS: A total of 40 patients suffering from non-rheumatoid wrist arthritis were enrolled in a randomized controlled trial comparing the ReMotion and Motec TWAs. Patient-rated and functional outcomes, radiological changes, blood metal ion levels, migration measured by model-based radiostereometric analysis (RSA), bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA), complications, loosening, and revision rates at two years were compared. RESULTS: Patient-Rated Wrist and Hand Evaluation (PRWHE) scores, abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire scores, and pain improved similarly and significantly in both groups. Wrist motion improved significantly in the Motec group only, and forearm rotation in the ReMotion group only. Cobalt (Co) and chromium (Cr) blood ion levels were significantly higher in the metal-on-metal (MoM) Motec group than in the metal-on-polyethylene (MoP) ReMotion group. Mean total translation was 0.65 mm (95% confidence interval (CI) 0.26 to 1.12) and 0.27 mm (95% CI 0.14 to 0.47) for the ReMotion carpal and radial components, and 0.32 mm (95% CI 0.22 to 0.45) and 0.26 mm (95% CI 0.20 to 0.34) for the Motec metacarpal and radial components, respectively. Apart from dorsal and volar tilts, which were significantly higher for the radial ReMotion than for the Motec component, no significant differences in absolute migration occurred. BMD around the radial components never returned to baseline. Almost one-third of patients required reoperation due to complications. Two ReMotion implants were revised to Motec TWAs due to carpal component loosening, and three Motec MoM articulations were revised to metal-on-polyether ether ketone due to painful synovitis. CONCLUSION: Both implants provided matched function and were stable at short-term follow-up, but with a high complication rate. This procedure should be restricted to specialist centres undertaking prospective analysis until its role is clarified.Cite this article: Bone Joint J 2022;104-B(10):1132-1141.


Assuntos
Artroplastia de Substituição , Prótese Articular , Artroplastia de Substituição/efeitos adversos , Artroplastia de Substituição/métodos , Cromo , Cobalto , Éteres , Seguimentos , Humanos , Cetonas , Polietilenos , Amplitude de Movimento Articular , Punho/cirurgia , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/cirurgia
20.
Sci Total Environ ; 852: 158468, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36075411

RESUMO

Plastics pollution is a global issue impacting every part of our environment. Tyre road wear particle (TRWP) plastics pollution is thought to be one of the largest pollution sources in urban environments. These plastics are also of concern due to the presence of additive chemicals, incorporated during manufacture, that can be released into the surrounding environment. This study aimed to provide information on concentrations of a range of anthropogenic plastics related pollutants in the Australian environment through a scoping study of surface water in 5 key urban centres around Queensland, Australia. Samples were analysed for a suite of 15 common tyre additive chemicals, TRWPs and 6 common high production polymers, and included the new transformation product of concern 6PPD-quinone which has recent reports of causing mass mortality events in certain aquatic species. The additives were ubiquitously detected (2.9-1440 ng/L) with 6PPD-quinone concentrations lower than in previous studies (<0.05-24 ng/L) and TRWPs detected at 18 of the 21 sites (

Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Monitoramento Ambiental , Polímeros , Água , Queensland , Polipropilenos , Austrália , Plásticos , Polietilenos , Quinonas
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