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1.
Mikrochim Acta ; 191(5): 265, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625451

RESUMO

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice. Golgi dots can be readily synthesized by coprecipitation of Golgi-F127, an amphiphilic polymer F127 modified with a Golgi apparatus targeting moiety, caffeic acid (CA), the responsive unit for O2·-, and red emissive carbon nanodots (CDs), which act as the reference signal. The fluorescence emission spectrum of the developed nanoprobe showed an intense peak at 674 nm, accompanied by a shoulder peak at 485 nm. As O2·- was gradually added, the fluorescence at 485 nm continuously increased; in contrast, the emission intensity at 674 nm assigned to the CDs remained constant, resulting in the ratiometric sensing of O2·-. The present ratiometric nanoprobe showed high selectivity for O2·- monitoring due to the specific recognition of O2·- by CA. Moreover, the Golgi dots exhibited good linearity with respect to the O2·- concentration within 5 to 40 µM, and the limit of detection (LOD) was ~ 0.13 µM. Additionally, the Golgi dots showed low cytotoxicity and an ability to target the Golgi apparatus. Inspired by these excellent properties, we then applied the Golgi dots to successfully monitor exogenous and endogenous O2·- levels within the Golgi apparatus. Importantly, with the help of Golgi dots, we determined that SD substantially elevated O2·- levels in the brain.


Assuntos
Encéfalo , Ácidos Cafeicos , Polietilenos , Polipropilenos , Privação do Sono , Animais , Camundongos , Complexo de Golgi , Suplementos Nutricionais
2.
Proc Inst Mech Eng H ; 238(4): 438-443, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38439747

RESUMO

With low wear rates shown by contemporary bearing materials of total hip prostheses, the standard deviation of wear rate is relatively high. Therefore, large sample sizes are needed for an adequate power of test. Because wear tests take a long time, it is practical to test several samples simultaneously. A new high-capacity, multidirectional wear test device, called the SuperCTPOD-200, was introduced. A 3 million-cycle wear test with an unprecedented sample size of 200 was performed for VEXLPE. The duration of the test was 6 weeks. The wear factor was normally distributed with a mean ± SD of 1.64 × 10-7 mm3/Nm ± 0.22 × 10-7 mm3/Nm (n = 200). The observation that SD was 13.1% of the mean can be useful in power analyses of future tests with other highly cross-linked polyethylenes. Burnishing was the most typical feature on the worn pins, which was in agreement with clinical findings on retrieved acetabular liners. The present study emphasizes statistics that often plays a minor role only in wear studies.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Teste de Materiais , Óxido de Alumínio , Polietilenos , Falha de Prótese
3.
ACS Appl Bio Mater ; 7(3): 1888-1898, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38349328

RESUMO

Garlic-derived exosome-like nanovesicles (GELNs) could function in interspecies communication and may serve as natural therapeutics to regulate the inflammatory response or as nanocarriers to efficiently deliver specific drugs. Staphylococcus aureus (S. aureus) is able to hide within host cells to evade immune clearance and antibiotics, leading to life-threatening infections. On-site detection and efficient treatment of intracellular S. aureus infection in wounds remain challenging. Herein, we report a thermosensitive, injectable, visible GELNs-based wound dressing, Van@GELNs/F127 hydrogel (gel Van@GELNs), which is H2O2-responsive and can slowly release vancomycin into host cells forS. aureus infection visualization and treatment in wounds. GELNs show inherent antibacterial activity, which is significantly enhanced after loading vancomycin. Both GELNs and Van@GELNs have the ability to be internalized by cells, so Van@GELNs are more effective than free vancomycin in killing S. aureus in RAW 264.7 macrophages. When applied to an S. aureus-infected wound on a mouse, the colorless HRP&ABTS/Van@GELNs/F127 solution immediately changes to a green hydrogel and shows better therapeutic effect than vancomycin. Thus, direct visualization by the naked eye and effective treatment of S. aureus infection in wounds are achieved by gel Van@GELNs. We anticipate gel Van@GELNs be applied for the theranostics of S. aureus infection diseases in the clinic in the near future.


Assuntos
Exossomos , Alho , Polietilenos , Polipropilenos , Infecções Estafilocócicas , Camundongos , Animais , Vancomicina/farmacologia , Vancomicina/uso terapêutico , Staphylococcus aureus , Peróxido de Hidrogênio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Bandagens , Hidrogéis/uso terapêutico , Hidrogéis/farmacologia
4.
Adv Healthc Mater ; 13(9): e2303305, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38277491

RESUMO

Nanomedicine in combination with immunotherapy has shown great potential in the cancer treatment, but phototherapeutic nanomaterials that specifically activate the immunopharmacological effects in deep tumors have rarely been developed due to limited laser penetration depth and tumor immune microenvironment. Herein, this work reports a newly synthesized semiconducting polymer (SP) grafted with imiquimod R837 and indoxmid encapsulated micelle (SPRIN-micelle) with strong absorption in the second near infrared window (NIR-II) that can relieve tumor immunosuppression and enhance the photothermal immunotherapy and catabolic modulation on tumors. Immune agonists (Imiquimod R837) and immunometabolic modulators (indoxmid) are covalently attached to NIR-II SP sensors via a glutathione (GSH) responsive self-immolation linker and then loaded into Pluronic F127 (F127) micelles by a temperature-sensitive critical micelle concentration (CMC)-switching method. Using this method, photothermal effect of SPRIN-micelles in deep-seated tumors can be activated, leading to effective tumor ablation and immunogenic cell death (ICD). Meanwhile, imiquimod and indoxmid are tracelessly released in response to the tumor microenvironment, resulting in dendritic cell (DC) maturation by imiquimod R837 and inhibition of both indoleamine 2,3-dioxygenase (IDO) activity and Treg cell expression by indoxmid. Ultimately, cytotoxic T-lymphocyte infiltration and tumor metastasis inhibition in deep solid tumors (9 mm) are achieved. In summary, this work demonstrates a new strategy for the combination of photothermal immunotherapy and metabolic modulation by developing a dual functional polymer system including activable SP and temperature-sensitive F127 for the treatment of deep solid tumors.


Assuntos
Nanopartículas , Neoplasias , Polietilenos , Polipropilenos , Humanos , Imiquimode/farmacologia , Polímeros/farmacologia , Micelas , Fototerapia/métodos , Neoplasias/tratamento farmacológico , Imunoterapia/métodos , Linhagem Celular Tumoral , Microambiente Tumoral
5.
J Shoulder Elbow Surg ; 33(7): 1465-1472, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38182025

RESUMO

BACKGROUND: Particle-induced osteolysis resulting from polyethylene wear remains a source of implant failure in anatomic total shoulder designs. Modern polyethylene components are irradiated in an oxygen-free environment to induce cross-linking, but reducing the resulting free radicals with melting or heat annealing can compromise the component's mechanical properties. Vitamin E has been introduced as an adjuvant to thermal treatments. Anatomic shoulder arthroplasty models with a ceramic head component have demonstrated that vitamin E-enhanced polyethylene show improved wear compared with highly cross-linked polyethylene (HXLPE). This study aimed to assess the biomechanical wear properties and particle size characteristics of a novel vitamin E-enhanced highly cross-linked polyethylene (VEXPE) glenoid compared to a conventional ultrahigh-molecular-weight polyethylene (UHMWPE) glenoid against a cobalt chromium molybdenum (CoCrMo) head component. METHODS: Biomechanical wear testing was performed to compare the VEXPE glenoid to UHMWPE glenoid with regard to pristine polyethylene wear and abrasive endurance against a polished CoCrMo alloy humeral head in an anatomic shoulder wear-simulation model. Cumulative mass loss (milligrams) was recorded, and wear rate calculated (milligrams per megacycle [Mc]). Under pristine wear conditions, particle analysis was performed, and functional biologic activity (FBA) was calculated to estimate particle debris osteolytic potential. In addition, 95% confidence intervals for all testing conditions were calculated. RESULTS: The average pristine wear rate was statistically significantly lower for the VEXPE glenoid compared with the HXLPE glenoid (0.81 ± 0.64 mg/Mc vs. 7.00 ± 0.45 mg/Mc) (P < .05). Under abrasive wear conditions, the VEXPE glenoid had a statistically significant lower average wear rate compared with the UHMWPE glenoid comparator device (18.93 ± 5.80 mg/Mc vs. 40.47 ± 2.63 mg/Mc) (P < .05). The VEXPE glenoid demonstrated a statistically significant improvement in FBA compared with the HXLPE glenoid (0.21 ± 0.21 vs. 1.54 ± 0.49 (P < .05). CONCLUSIONS: A new anatomic glenoid component with VEXPE demonstrated significantly improved pristine and abrasive wear properties with lower osteolytic particle debris potential compared with a conventional UHMWPE glenoid component. Vitamin E-enhanced polyethylene shows early promise in shoulder arthroplasty components. Long-term clinical and radiographic investigation needs to be performed to verify if these biomechanical wear properties translate to diminished long-term wear, osteolysis, and loosening.


Assuntos
Artroplastia do Ombro , Teste de Materiais , Polietilenos , Desenho de Prótese , Falha de Prótese , Prótese de Ombro , Vitamina E , Humanos , Artroplastia do Ombro/métodos , Fenômenos Biomecânicos , Tamanho da Partícula , Osteólise/etiologia , Osteólise/prevenção & controle , Articulação do Ombro/cirurgia
6.
Sci Total Environ ; 906: 167619, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37806594

RESUMO

Microplastics (MPs) and antibiotic resistance genes (ARGs) are both enriched in soil-vegetable systems as a consequence of the prolonged use of agricultural mulches. MPs can form unique bacterial communities and provide potential hosts for ARGs. Therefore, MPs stress may promote the spread of ARGs from soil to crops. Increasing ARGs pollution in soil-vegetable system. In our research, we investigated the distribution and major driving elements of antibiotic resistance genes in the soil-vegetable system under microplastic stress. The results showed that MPs treatment decreased the relative abundance of ARGs in non-rhizosphere soil. High concentrations of MPs promoted the enrichment of tetracycline antibiotic resistance genes in rhizosphere soil. MPs treatment promoted the enrichment of ARGs and mobile genetic elements (MGEs) in lettuce tissues, and the overall abundance of ARGs in root after 0.5 %, 1 %, and 2 % (w/w, dry weight) polyethylene (PE) administration was considerably higher compared to that in the untreated group (p < 0.05). At the same time, high PE concentrations promoted the spread of sulfa ARGs from root to leaf. MPs also impacted the bacterial communities in the soil-plant system, and the changes in ARGs as well as MGEs in each part of the soil-vegetable system were significantly correlated with the bacterial diversity index (p < 0.05). Correlation analysis and network analysis showed that bacterial communities and MGEs were the main drivers of ARGs variation in soil-lettuce systems.


Assuntos
Microplásticos , Verduras , Genes Bacterianos , Solo , Plásticos , Antibacterianos/farmacologia , Microbiologia do Solo , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Lactuca , Polietilenos
7.
Food Res Int ; 164: 112321, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737915

RESUMO

Fruit peels are rich source of bioactive compounds such as polyphenols, flavonoids, and antioxidants but are often discarded as waste due to limited pharmaceutical and nutraceutical applications. This study aimed to valorise pomegranate and citrus fruit peel into green synthesised silver nanoparticles (AgNPs) in order to modify cellulose-based wrapping material for prospective food packaging applications and propose an alternate and sustainable approach to replace polyethene based food packaging material. Four different concentrations of AgNO3 (0.5 mM, 1 mM, 2 mM, and 3 mM) were used for green synthesis of AgNPs from fruit peel bioactive, which were characterised followed by phytochemical analysis. Ultraviolet-Visible spectroscopy showed surface plasmon resonance at 420 nm, XRD analysis showed 2θ peak at 27.8°, 32.16°, 38.5°, 44.31°, 46.09°, 54.76°, 57.47°, 64.61° and 77.50° corresponding to (210), (122), (111), (200), (231), (142), (241), (220) and (311) plane of face centred cubic crystal structure of AgNPs. Fourier-transform infrared spectroscopy analysis of AgNPs green synthesised from pomegranate and kinnow peel extract showed a major peak at 3277, 1640 and 1250-1020 1/cm while a small peak at 2786 1/cm was observed in case of pomegranate peel extract which was negligible in AgNPs synthesized from kinnow peel extract. Particle sizes of AgNPs showed no statistically significant variance with p > 0.10 and thus, 2 mM was chosen for further experimentation and modification of cellulose based packaging material as it showed smallest average particle size. Zeta potential was observed to be nearly neutral with a partial negative strength due to presence of various phenolic compounds such as presence of gallic acid which was confirmed by ultrahigh performance liquid chromatography-photodiode array(UHPLC-PDA) detector. Thermal stability analysis of green synthesised AgNPs qualified the sterilisation conditions up to 100 °C. AgNPs green synthesized from both the peel extracts had higher polyphenolic content, antioxidant and radical scavenging activity as compared to peel extracts without treatment (p < 0.05). The cellulose based food grade packaging material was enrobed by green synthesised AgNPs. The characterisation of modified cellulose wrappers showed no significant difference in thickness of modified cellulose wrappers as compared with untreated cellulose wrapper (p > 0.42) while weight and grammage increased significantly in modified cellulose wrapper (p < 0.05). The colour values on CIE scale (L*, a* and b*) showed statistically significant increase in yellow and green colour (p < 0.05) for modified cellulose wrappers as compared to control wrapper. The oxygen permeability coefficient, water vapour permeability coefficient, water absorption capacity and water behaviour characteristics (water content, swelling degree and solubility) showed significant decrease (p < 0.05) for modified cellulose wrapper as compared to control wrapper. A uniform distribution and density of green synthesised AgNPs across cellulose wrapper matrix was observed through scanning electron microscopy (SEM) images with no significant aggregation, confirming successful enrobing and stable immobilisation of nanoparticles from cellulose matrix. A seven-day storage study of bread wrapped in modified and control cellulose wrappers showed delayed occurrence of microbial, yeast and mould count in bread packaged in modified cellulose wrappers and thus, resulting in shelf life extension of bread. The results are encouraging for the potential applications of modified cellulose wrappers to replace polyethene based food packaging.


Assuntos
Frutas , Nanopartículas Metálicas , Frutas/química , Prata/análise , Pão , Nanopartículas Metálicas/química , Extratos Vegetais/química , Antioxidantes/análise , Celulose/análise , Expectativa de Vida , Polietilenos/análise
8.
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
9.
Chemosphere ; 307(Pt 3): 135952, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35964716

RESUMO

Slaughterhouse wastewater (SWW) contains a significant volume of highly polluted organic wastes. These include blood, fat, soluble proteins, colloidal particles, suspended materials, meat particles, and intestinal undigested food that consists of higher concentrations of organics such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen and phosphorus hence an efficient treatment is required before discharging into the water bodies. The effluent concentrations and performance of simultaneous sequential batch biofilm reactor (SBBR) with recycled plastic carrier media support are better than the local single-stage sequential batch reactor (SBR), which is lacking in the literature in terms of COD, NH3, NO3, and PO4 treatment efficiency. The present study reports a novel strategy to remove the above mentioned contaminants using an intermittently aerated SBBR with recycled plastic carrier media support along with simultaneous nitrification and denitrification. The central composite design was evaluated to optimize the treatment performance of seven different process variables including; different alternating conditions (Oxic/anoxic) for aeration cycles (3/2 h in a 6 h cycle, 6/5 h in a 12 h cycle and 9/8 h in an 18 h cycle) and hydraulic retention time (6, 12 and 18 h). The average removal efficiencies are 94.5% for NH3, 93% for NO3 and 90.1% for PO4, and 99% for COD. The study reveals that the denitrification in the post-anoxic phase was more efficient than the pre-anoxic phase for pollutant removal and maintaining higher quality effluent. The effluent concentrations and performance of simultaneous SBBR with recycled polyethylene carrier support media were better than local SBR system in terms of COD, NH3, NO3 and PO4 treatment efficiency. Results stipulated the suitability of SBBR for wastewater treatment and reusability as a sustainable approach for wastewater management under optimum conditions.


Assuntos
Poluentes Ambientais , Águas Residuárias , Matadouros , Biofilmes , Reatores Biológicos , Nitrogênio/metabolismo , Oxigênio/metabolismo , Fósforo , Plásticos , Polietilenos , Eliminação de Resíduos Líquidos/métodos , Água
10.
Int Endod J ; 55(10): 1026-1041, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35791796

RESUMO

AIM: Natural substances such as omega-3 have been used in the medical field due to their numerous properties and, in particular, modulating effect on the systemic and local inflammatory processes. Thus, this study evaluated the influence of omega-3 supplementation on the subcutaneous tissue response of endodontic sealers in Wistar Rats. METHODOLOGY: Polyethylene tubes were implanted in the subcutaneous tissue of 48 animals (one empty for control and three filled with Sealapex, AH Plus or Endofill). The animals were treated with omega-3 (TO) or water (TW). Treatments started 15 days before implantation until euthanasia. After 5, 15 and 30 days (n = 8), animals were euthanized and polyethylene tubes and surrounding tissue were removed and processed for histological analysis. The inflammatory reaction was analysed by Haematoxylin and Eosin stain and immunolabelling for IL-6 and TNF-α. The collagen maturity was analysed by picrosirius red stain and calcium deposition by von Kossa stain and polarized light. Results were statistically analysed (p < .05). RESULTS: Amongst TW sealer groups, Endofill evoked a more intense inflammatory infiltrate compared with AH Plus and control in the 30-day period (p = .009). However, in TO sealer groups, there was no difference amongst the sealers and control in all periods (p > .05). Comparing each sealer as a function of the supplementation with water or omega-3, there are differences for Endofill (p = .001) and Sealapex (p = .005) in the 30-day period, presenting lower inflammatory infiltrate in the animals treated with omega-3. A higher percentage of immature fibres was observed at 15 and 30 days in the TO group, compared with the TW group (p < .05). The deposition of calcium particles was observed only by Sealapex in all periods, despite the supplementation procedure. CONCLUSIONS: Omega-3 supplementation influence the tissue reactions of endodontic sealers, modulating inflammation, the immunolabelling of IL-6 and TNF-α, the repair process and it does not interfere with calcium deposition.


Assuntos
Materiais Restauradores do Canal Radicular , Tela Subcutânea , Animais , Cálcio , Suplementos Nutricionais , Resinas Epóxi , Inflamação , Interleucina-6/farmacologia , Teste de Materiais , Polietilenos/farmacologia , Ratos , Ratos Wistar , Materiais Restauradores do Canal Radicular/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Água
11.
Waste Manag Res ; 40(11): 1637-1644, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35642625

RESUMO

The pyrolysis of spent coffee grounds (SCG) and polymers was examined as a waste treatment option for energy recovery and carbon sequestration. Rice straw-derived biochar was used as control biochar to evaluate the sorption capacity and energy production capability of SCG-derived biochar. SCG are characterised by high levels of volatile matter, rendering them suitable as an energy source. SCG were converted to biochar, bio-oil, and syngas via pyrolysis, with yields of 22%, 33%, and 45%, respectively. The high heating value (HHV) of the biochar and bio-oil was 20.6 and 22.9 MJ kg-1, respectively, indicating that they could be used as supplementary fuels. Co-pyrolysis with polymers (20 v v%-1) increased the HHV of biochar. Accordingly, the maximum production of CH4 and H2 increased from 0.3 and 0.04 mmol g-1 to 3.4-6.3 and 0.8-1.3 mmol g-1, respectively. Polystyrene most strongly enhanced the yields of CH4 and H2, followed by polypropylene and polyethylene; this order was likely to be in accordance with the number of carbon and hydrogen atoms present in the monomers. Similar to rice straw-derived biochar, the biochar produced from SCG demonstrated a high sorption capacity for 2,4-dinitrotoluene and chromate due to its high carbon content and anion exchange capacity, respectively. Laboratory pot tests revealed that the coffee grounds-derived biochar was able to increase the growth of young radish. Our results suggest that the pyrolysis of SCG and polymer may be a promising option for waste treatment, energy production, and carbon sequestration.


Assuntos
Oryza , Pirólise , Biomassa , Carbono , Carvão Vegetal , Cromatos , Café , Hidrogênio , Óleos de Plantas , Polietilenos , Polímeros , Polifenóis , Polipropilenos , Poliestirenos
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 278: 121366, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35588603

RESUMO

Red-emitting distyryl substituted BODIPY dyes are among the most promising luminophors for bioimaging and optics applications. However, the practical application of BODIPYs is limited due to their high hydrophobicity and tendency to aggregate in aqueous organic solutions and solid phase. In this article, we propose an elegant solution to this problem. To this end, we carried out the detailed experimental and quantum-chemical study of the structural and spectral features of BF2-ms-phenyl-5,5'-bis(4-dimethylaminostyryl)-3,3'-dimethyl-2,2'-dipyrromethene (distyryl-BDP). The particular attention was paid to analysis of high sensitivity of the distyryl-BDP spectral characteristics to the solvent properties, and also the aggregation behavior features both in water-organic media and in mono- and multilayer Langmuir-Schaefer films. We selected the best conditions to obtain the hydrophilic micellar structures of distyryl-BDP with Pluronic® F127 having a high efficiency of dye solubilization. This method increasing the solubility improves the distyryl-BDP transport efficiency in physiological aqueous media. The aqueous solutions of distyryl-BDP-Pl micelles show the intense fluorescence in the phototherapy window region (λfl = 739 nm).


Assuntos
Compostos de Boro , Micelas , Compostos de Boro/química , Corantes , Polietilenos , Polipropilenos , Água/química
13.
Int J Biol Macromol ; 210: 403-414, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35526768

RESUMO

Curcumin, a principal component of Curcuma longa, has a long history of being used topically for wound healing. However, poor aqueous solubility of curcumin leads to poor topical absorption. Recently, gelatin based gel has been reported to overcome this issue. However, the release of curcumin from gelatin gel in the bioavailable or easily absorbable form is still a challenge. The present study reports the development of a composite gel prepared from gelatin, F127 and lecithin using temperature dependant gelation and loading of curcumin within it. Notably, the composite gel facilitated the release of curcumin entrapped within vesicles of ~400 nm size. Further, the composite gel exhibited increase in the storage modulus or gel strength, stability, pore size and hydrophobicity as compared to only gelatin gel. Finally, wound healing assay in murine model indicated that curcumin delivered through composite gel showed a significantly faster healing as compared to that delivered through organic solvent. This was also validated by histopathological and biochemical analysis showing better epithelization and collagen synthesis in the group dressed with curcumin containing composite gel. In conclusion, composite gel facilitated the release of bioavailable or easily absorbable curcumin which in turn enhanced the wound healing.


Assuntos
Curcumina , Animais , Curcumina/farmacologia , Gelatina , Lecitinas , Camundongos , Polietilenos , Polipropilenos , Cicatrização
14.
J Mech Behav Biomed Mater ; 127: 105072, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35033983

RESUMO

A novel polymer-on-metal hip joint prosthesis design that makes use of uni-directional articulations was developed and tested in this work. The new implant was tested using two polymer variants, virgin ultra-high molecular weight polyethylene (UHMWPE), and Vitamin E-infused highly crosslinked polyethylene (VEHXPE). The degrees of freedom of the ball-and-socket are reproduced by three cylindrical orthogonally-aligned articulations. This unconventional design leverages on the molecular orientation hardening mechanisms of the polyethylene and increased contact area to minimize wear. An experimental hip joint simulator was used to compare the gravimetric wear of the conventional ball-on-socket and the new implant. The new prosthesis including UHMWPE components produced a 78% reduction in wear, whereas the new prosthesis with VEHXPE components produced a 100% reduction in wear, as no measurable wear was detected. Machining marks on the acetabular cups of the new prosthesis were retained for both polyethylene variants, further demonstrating the low levels of wear exhibited by the new implants. Both polyethylene materials produced particles in the range of 0.1-1.0 µm, which are the most biologically active. Nonetheless, the extremely low wear rates are likely to induce minimal osteolysis effects. Furthermore, the novel design also offers an increase of more than 24% in the range of motion in flexion/extension when compared to a dual-mobility hip implant. A prototype of the prosthesis was implanted into a Thiel-embalmed human cadaver during a mock-surgery, which demonstrated high resistance to dislocation and the possibility of performing a figure of four position.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Acetábulo/cirurgia , Articulação do Quadril/cirurgia , Humanos , Teste de Materiais , Polietileno , Polietilenos , Desenho de Prótese , Falha de Prótese , Vitamina E
15.
Chemosphere ; 291(Pt 2): 132984, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34801568

RESUMO

Microplastics are an emerging threat to soils, but little is known about their effects on soil nitrogen (N) and phosphorus (P) cycling. In this study, a three-month soil incubation experiment has been conducted to analyze the effects of polyethene (PE) and polypropylene (PP) microplastics in sizes of 0-1 mm and 1-5 mm on soil available phosphate, nitrate, and ammonium contents under different fertilization regimes. Soil phosphorus and nitrogen availability were continuously determined in-situ by ion-exchange membrane method during the incubation. Microplastic surface chemical composition and the specific surface area were analyzed by FTIR and BET, respectively. The 16s rRNA sequencing of soil bacterial communities as well as soil pH have been determined after the incubation. The results showed that the presence of microplastics could significantly (P < 0.05) decrease soil available phosphate content from 122.61 mg P L-1 to 63.43 mg P L-1. The addition of PP microplastics could significantly increase soil available ammonium content from 0.94 mg N L-1 to 1.53 mg N L-1. Since microplastics had undetectable specific surface area and limited effects on soil microorganisms, adsorption and microorganism alteration functions might not be the main drivers of microplastic effects on soil phosphorus and nitrogen.


Assuntos
Microplásticos , Solo , Nitrogênio , Fósforo , Plásticos , Polietilenos , Polipropilenos , RNA Ribossômico 16S , Microbiologia do Solo
16.
J Biomed Mater Res B Appl Biomater ; 110(6): 1306-1318, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34931730

RESUMO

In this study, a ultra-high molecular weight polyethylene (UHMWPE) braided structure was surface modified with low temperature plasma and was coated with cationized gelatin and hyaluronic acid to improve its biocompatibility for the reconstruction of an anterior cruciate ligament (ACL). The ligament was studied for its various mechanical properties. Surface modifications were studied through FESEM. Biological compatibility of the ligament was assessed in accordance to ISO 10993 standard. Tensile strength of the UHMWPE reconstructed ligament ranges between 2628 and 5937 N; maximum tensile strength was attained in 1600 denier 2/2 pattern of triple braided structure along with higher strain at failure of 36.1%. In 1600 denier 2/2 pattern of triple braid structure, the linear stiffness was found to be high at 375 N/mm. Among the developed materials, four braided structures namely as 800 denier 2/2 pattern of double braids and triple braids, 1600 denier 1/1 pattern of double braid and 2/2 pattern of triple braid were found to be mechanically suitable. Specifically, the 1600 denier 2/2 pattern of triple braid having higher mechanical properties was selected for coating. The results of in-vitro cytotoxicity and genotoxicity confirmed the extract of ACL to non-toxic and non-mutant. Furthermore, in-vivo analysis of the extract and the coated ACL graft proved the ligament to be non-irritant, non-sensitizer and also found to promote new tissue formation around the graft. Based on the results, the CG and HA coated ACL graft were concluded to be biocompatible and having considerable potential as an alternate for autograft/allograft.


Assuntos
Lesões do Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/cirurgia , Humanos , Teste de Materiais , Extratos Vegetais , Polietilenos
17.
J Nanosci Nanotechnol ; 21(11): 5688-5693, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33980381

RESUMO

Even with all the recent technological improvements, cancer remains to be the disease with the highest impact on global health. Due to obviously disadvantages or limitations on traditional therapy, researchers are engaged to search for safely and effective methods in cancers' therapy. Photothermal therapy (PTT) has been employed in treating cancers and several of other diseases. In this study, novel thermosensitive and targeting nanoparticle, C225-silane-F127/gold nanorod (C-SFGR) combined with PTT was investigated in EGFR-overexpressing xenografts mice model. For better light to heat transformation exposed with 808 nm near-infrared (NIR) laser, the diameter of thermosensitive C-SFGR was designed at about 120 nm. To address the biocompatibility, the viability of A549 cell line was greater than 80% under high concentrations of C-SFGR (1,000 µg/mL), indicating its low cytotoxicity. After intravenous injection of C-SFGR and combined with NIR treatment for 2 min in A549 bearing mice, tumors were almost completely shriveled after 2 weeks. For developing as theranostic agent, C-SFGR was then labeled with 67Ga, with radiochemical purity over 98%. These present results suggest that C-SFGR could be also applied as a SPECT-imaging agent and as an effective antitumor agent.


Assuntos
Hipertermia Induzida , Nanotubos , Animais , Linhagem Celular Tumoral , Ouro , Camundongos , Fototerapia , Terapia Fototérmica , Polietilenos , Polipropilenos , Silanos/toxicidade
18.
Mater Sci Eng C Mater Biol Appl ; 124: 112040, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33947540

RESUMO

To avoid catastrophic bacterial infection in prosthesis failure, ultrahigh molecular weight polyethylene (UHMWPE), a common bearing material of artificial joints, has been formulated with antibiotics to eliminate bacteria locally at the implant site. However, the pressing issues regarding cytotoxic effects and evolution of drug resistant bacteria necessitates the development of bio-friendly bacteriostat with long bacteriostatic efficacy. Herein, tea polyphenol extracted from nature source was introduced in UHMWPE as a biogenic antimicrobial. Controlled antimicrobial activity was achieved by chemical crosslinking to regulate the release of the tea polyphenol. In addition, the crosslinking efficiency of UHMWPE blends with high loaded tea polyphenol was significantly improved in comparison to radiation crosslinking. The immobilized tea polyphenols also enhanced the oxidation stability of the UHMWPE, which is essential to prolong the service life in vivo and the storage time in vitro. The blends presented good biocompatibility, despite cell repellent on the highly crosslinked surface. Chemically crosslinked tea polyphenol/UHMWPE exhibited feasible properties for total joint implants, which is promising for clinical application.


Assuntos
Artroplastia de Substituição , Polifenóis , Teste de Materiais , Peso Molecular , Polietilenos , Polifenóis/farmacologia , Chá , Tiram
19.
J Biomater Appl ; 35(9): 1168-1179, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33356787

RESUMO

Ultra-high molecular weight polyethylene (UHMWPE) can be made radiopaque for medical imaging applications through the diffusion of an iodised oil-based contrast agent (Lipiodol Ultra Fluid). A similar process is used for Vitamin E incorporated polyethylene which provides antioxidant properties. This study aimed to investigate the critical long-term properties of oil-infused medical polyethylene after 4 weeks of accelerated thermal ageing. Samples treated with an oil (Vitamin E or Lipiodol) had a higher oxidation stability than currently used medical grade polyethylene, indicated by a smaller increase in oxidation index after ageing (Vitamin E + 36%, Lipiodol +40%, Untreated +136%, Thermally treated +164%). The tensile properties of oil treated polyethylene after ageing were significantly higher than the Untreated and Thermally treated controls (p<0.05) indicating less mechanical degradation. There was also no alteration in the percentage crystallinity of oil treated samples after ageing, though the radiopacity of the Lipiodol treated samples reduced by 54% after ageing. The leaching of oil with time was also investigated; the leaching of Lipiodol and Vitamin E followed the same trend and reached a steady state by two weeks. Overall, it can be concluded that the diffusion of an oil-based fluid into polyethylene not only increases the oxidative and chemical stability of polyethylene but also adds additional functionality (e.g. radiopacity) providing a more suitable material for long-term medical applications.


Assuntos
Materiais Biocompatíveis/química , Óleo Etiodado/química , Polietilenos/química , Antioxidantes/química , Varredura Diferencial de Calorimetria , Meios de Contraste/química , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Resistência à Tração , Fatores de Tempo , Vitamina E/química , Microtomografia por Raio-X
20.
Zhongguo Zhong Yao Za Zhi ; 45(21): 5177-5183, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33350233

RESUMO

In the current study, schisandrin B(SchB)-loaded F127 modified lipid-polymer hybrid nanoparticles(SchB-F-LPNs) were developed to improve the inhibition of breast cancer lung metastasis. Modified nanoprecipitation method was used to prepare SchB-F-LPNs. The nanoparticles were spherical in shape with shell-core structure by TEM observation. SchB-F-LPNs showed a mean particle size of(234.60±6.11) nm with zeta potential of(-5.88±0.49) mV. XRD results indicated that SchB existed in the nanoparticles in an amorphous state. The apparent permeability coefficient through porcine mucus of F-LPNs was 1.43-fold of that of LPNs as shown in the in vitro mucus penetration study. The pharmacokinetics study showed that the C_(max) of SchB was(369.06±146.94) µg·L~(-1),(1 121.34±91.65) µg·L~(-1) and(2 951.91±360.53) µg·L~(-1) respectively in SchB suspensions group, SchB-LPNs group and SchB-F-LPNs group after oral administration in rats. With SchB suspensions as the reference formulation, the relative bioavailability of SchB-F-LPNs was 568.60%. SchB-F-LPNs inhibited the morphological change during transforming growth factor-ß1(TGF-ß1)-induced epithelial-mesenchymal transition. In addition, SchB-F-LPNs significantly decreased the number of metastatic pulmonary nodules in 4 T1 tumor-bearing mice, suggesting that SchB-F-LPNs may inhibit the metastasis of breast cancer. These results reveal the promising potential of SchB-F-LPNs in treatment of breast cancer lung metastasis.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Animais , Ciclo-Octanos , Lignanas , Lipídeos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Compostos Policíclicos , Polietilenos , Polímeros , Polipropilenos , Ratos , Suínos
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