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1.
Int Orthop ; 48(5): 1271-1275, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38403732

RESUMEN

PURPOSE: The optimal timing of surgery after traumatic rotator cuff tears (RCT) is unclear, with its impact on functional outcomes under debate. This study aimed to review functional outcomes after RCT repair in patients who underwent early vs delayed surgery at our unit. METHODS: This was single-centre retrospective evaluation. Patients with an acute traumatic RCT that underwent repair between 2017 and 2019 and had local follow-up were included and placed into two groups: early surgery (within 6 months from injury) and delayed surgery (more than 6 months from injury). Patient demographics, RCT data and pre- and post-operative (after 12 months) Oxford Shoulder Score (OSS) were extracted from medical records. Data was analysed to compare OSS scores between groups, as well as the effect of cuff tear sizes on OSS scores. RESULTS: Forty-nine patients were included in the analysis (15 early, 34 delayed). There were no significant differences in age, sex or cuff tear sizes between groups. No difference was identified in the mean post-operative OSS between early vs delayed groups (40.9 ± 6.34 vs 40.5 ± 7.65, p = 0.86). The mean improvement in OSS after surgery was also similar between groups (22.5 ± 7.81 vs 20.97 ± 7.19, p = 0.498). Having a large or massive RCT did not worsen OSS compared to small or medium RCT (p = 0.44), even when stratified by early or delayed surgery. CONCLUSION: Delayed surgery for traumatic RCT greater than 6 months from injury did not negatively impact long-term functional outcomes at our unit. Patients should be reassured as applicable before surgery in the event of prolonged or unavoidable delays.


Asunto(s)
Laceraciones , Lesiones del Manguito de los Rotadores , Humanos , Lesiones del Manguito de los Rotadores/cirugía , Manguito de los Rotadores/cirugía , Resultado del Tratamiento , Artroscopía , Rotura , Estudios Retrospectivos , Rango del Movimiento Articular
2.
Int J Biol Macromol ; 258(Pt 2): 128910, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38141710

RESUMEN

Polyvinyl alcohol (PVA) was blended with high amylose starch (HAS) at a ratio of 3:1, and reinforced with montmorillonite (MMT K10) at different concentrations (1, 2, 5, and 7 % w/w of polymers) and anthocyanins (ANT) to develop an active and smart packaging film. MMT addition enhanced the film's mechanical, barrier, thermal, and water resistance properties. Incorporating ANT extracted from roselle calyx into the optimal nanocomposite film (MMT/PVA-HAS II) increased the films' antioxidant, pH-response, and antibacterial properties. FTIR, XRD, and SEM confirmed the intermolecular interactions and even distribution of ANT and MMT in the film matrix. Release rate of ANT was dependent on type of simulant, with higher rate in aqueous solutions compared to alcoholic/fatty food simulants, and cytotoxicity evaluation proved safety of films for food packaging applications. Storage experiments confirmed the potential applicability of the novel halochromic smart film as a promising candidate for monitoring chicken spoilage under abusive storage conditions.


Asunto(s)
Nanocompuestos , Almidón , Animales , Amilosa , Alcohol Polivinílico , Pollos , Bentonita , Antocianinas , Embalaje de Alimentos , Agua , Carne
3.
Sci Rep ; 13(1): 12623, 2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37537206

RESUMEN

CO2 laser ablation is a rapid and precise technique for machining microfluidic devices. And also, low-cost epoxy resin (ER) proved the great feasibility of fabricating these devices using the CO2 laser ablation technique in our previous studies. However, such a technique has shown negative impacts on such ER-based microfluidics as rough surface microchannels, and thermal defects. Therefore, incorporating different proportions of boric acid (BA) into epoxy resin formulation was proposed to obviate the genesis of these drawbacks in ER-based microfluidics. The structural and optical properties of plain ER- and B-doped ER-based chips were characterized by Fourier transform infrared (FT-IR) and UV/Vis spectral analyses. Furthermore, their thermal properties were studied by thermo-gravimetric (TGA) and differential scanning calorimetric (DSC) analysis. A CO2 laser ablation machine was used in vector mode to draw the designed micro-channel pattern onto plain ER- and B-doped ER-based chips. The quality of microchannels engraved onto these chips was assessed using 3D laser microscopy. This microscopic examination showed a noticeable reduction in the surface roughness and negligible bulge heights in the laser-ablated micro-channels. On the other hand, overall and specific migration using gravimetric methods and gas chromatography-mass spectrometry (GC-MS), respectively, and PCR compatibility test were performed to explore the convenience of these micro-plates for the biological reactions. These findings validated the applicability of B-doped ER-based microfluidics in bio-analytical applications as a result of the effective role of boric acid in enhancing the thermal properties of these chips leading to get micro-channels with higher quality with no effect on the biological reactions.

4.
Polymers (Basel) ; 15(2)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36679187

RESUMEN

An important problem for the oil industry is the deposition of paraffin on pipelines during the transit of crude oil and restart processes at low temperature. In this regard, the need for suitable methods of wax deposition has attracted substantial attention. Therefore, pour point depressants (PPDs) are considered a critical processing aid to modify the paraffin crystallization and improve the flow of waxy crude oil. The effect of pendants in comb-type copolymers on the ability of crude oil to flow in the cold is examined in the current study. Such PPDs were first created by the free radical polymerization of maleic anhydride with benzyl oleate to create the poly (benzyl oleate-co-maleic anhydride). The resultant copolymer was then aminated with alkyl amine (stearyl amine) (C18H39N) to form pendant alkyl amine chains. The esterified copolymers were structurally characterized by Fourier Transform Infrared, X-ray diffraction spectral analysis, and scanning electron microscopy. Moreover, the potential interactions between PPD and waxes were investigated by using differential scanning calorimetry, X-ray diffraction, and light microscopy. The obtained PPDs, which are effective at a dose of 2000 ppm, were able to reduce the pour point by up to 3 °C. The viscosity and yield stress of the petroleum waxy crude oil were revealed by rheometer.

5.
Sci Rep ; 12(1): 20673, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36450774

RESUMEN

Novel pectin-based films reinforced with crystalline nanocellulose (CNC) and activated with zinc oxide nanoparticles (ZnO NPs) were prepared by solvent-casting method. Film ingredients enhanced UV-blocking, thermal, and antibacterial properties of active films against well-known foodborne pathogens. Optimal active films exhibited higher mechanical, water vapor barrier properties compared to pristine pectin films. SEM confirmed the even distribution of CNC and ZnO NPs in pectin matrix and their interactions were proven using FTIR. Wrapping hard cheese samples artificially contaminated with Staphylococcus aureus and Salmonella enterica with the ternary nanocomposite film at 7 °C for 5 days significantly reduced the total population counts by at least 1.02 log CFU/g. Zn2+ migrating to wrapped cheese samples was below the specific limit (5 mg/kg), confirming their safety for food contact. Overall, ZnO/CNC/pectin nanocomposite films represent promising candidates for active food packaging as safe, eco-friendly alternatives for synthetic packaging materials.


Asunto(s)
Queso , Nanocompuestos , Óxido de Zinc , Embalaje de Alimentos , Pectinas
6.
Polymers (Basel) ; 14(16)2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-36015488

RESUMEN

Deposition of wax is considered one of the most significant culprits in transporting petroleum crude oils, particularly at low temperatures. When lowering pressure and temperature during the flow of crude oil, the micelle structure of the crude oil is destabilized, allowing oil viscosity to increase and precipitating paraffin (wax) in the well tubulars and pipeline, which increase the complexity of this culprit. These deposited substances can lead to the plugging of production and flow lines, causing a decline in oil production and, subsequently, bulk economic risks for the oil companies. Hence, various approaches have been commercially employed to prevent or remediate wax deposition. However, further research is still going on to develop more efficient techniques. These techniques can be categorized into chemical, physical, and biological ones and hybridized or combined techniques that apply one or more of these techniques. This review focused on all these technologies and the advantages and disadvantages of these technologies.

7.
Polymers (Basel) ; 13(16)2021 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-34451178

RESUMEN

In this study, chemically cross-linked PVA/PAMPS membranes have been prepared to be used in direct methanol fuel cells (DMFCs). The structural properties of the resultant membrane were characterized by use FTIR and SEM. Additionally, their thermal stability was assessed using TGA. Moreover, the mechanical properties and methanol and water uptake of membrane was studied. The obtained FTIR of PVA/PAMPS membranes revealed a noticeable increase in the intensity of adsorption peaks appearing at 1062 and 1220 cm-1, which correspond to sulfonic groups with the increasing proportion of PAMPS. The thermograms of these polyelectrolyte membranes showed that their thermal stability was lower than that of PVA membrane, and total weight loss gradually decreased with increasing the PAMPS. Additionally, the functional properties and efficiency of these polyelectrolyte membranes were significantly improved with increasing PAMPS proportion in these blends. The IEC of polymer blend membrane prepared using PVA/PAMPS ratio of 1:1 was 2.64 meq/g. The same membrane recorded also a methanol permeability coefficient of 2.5 × 10-8 cm2/s and thus, its efficiency factor was 4 × 105 greater than that previously reported for the commercial polyelectrolyte membrane, Nafion® (2.6 × 105). No significant increase in this efficiency factor was observed with a further amount of PAMPS. These results proved that the PVA:PAMPS ratio of 1:1 represents the optimum mass ratio to develop the cost-effective and efficient PVA/PAMPS blend membranes for DMFCs applications.

8.
J Pharm Biomed Anal ; 54(1): 242-7, 2011 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-20828963

RESUMEN

Currently, there are no analytical methods available in the literature that can simultaneously separate and quantitate residual levels of acetone, methylene chloride, n-butyl ether and dimethylsulfoxide in Betamethasone valerate active pharmaceutical ingredient (API). This paper describes the development and validation of a simple, efficient, accurate and robust static headspace gas chromatography method for the determination of high and low boiling residual solvents, namely acetone, methylene chloride, n-butyl ether and dimethylsulfoxide, in Betamethasone valerate API. This method has been demonstrated to be accurate, linear, precise, reproducible, specific and robust for its intended purpose. Quantitation limits (QL) for acetone, methylene chloride and n-butyl ether are 20 ppm (20 µg/g of API) and 50 ppm (50 µg/g of API) for dimethylsulfoxide. Several other APIs (Loratadine and a few other corticosteroid compounds) were analyzed using the conditions of this method to evaluate and assess the versatility of this method for the purpose of residual solvents analysis for a wide range of APIs. The results of this evaluation strongly indicates that this method can be readily used (as-is or with minor modifications) to determine both low and high boiling residual solvents present in a wide range of APIs.


Asunto(s)
Antiinflamatorios/análisis , Valerato de Betametasona/análisis , Cromatografía de Gases/métodos , Acetona/química , Antiinflamatorios/química , Valerato de Betametasona/química , Técnicas de Química Analítica , Química Farmacéutica/métodos , Cromatografía/métodos , Dimetilsulfóxido/química , Preparaciones Farmacéuticas/análisis , Reproducibilidad de los Resultados , Solventes/química , Temperatura , Factores de Tiempo
9.
J Agric Food Chem ; 57(6): 2529-35, 2009 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-19292471

RESUMEN

Zein, a predominant corn protein, is an alcohol-soluble protein extracted from corn and is characterized by unique film-forming properties. The characteristic brittleness of zein diminishes its usefulness as a structural material. The objective of this work was to study the effect of gamma-irradiation on improving the performance of zein films in packaging applications. This goal has been achieved by irradiating zein film-forming solutions with various doses of gamma-rays, namely, 10, 20, 30, and 40 kGy at dose rate of 10.5 kGy/h, using a Co(60) gamma-radiation source. The impact of radiation process on the structural properties has been explored through far-UV CD spectral analysis and scanning electron microscopy. Additionally, viscosity changes that reflect the effect of radiation treatment on degradation and/or cross-linking of protein chains have been measured. However, improvements in the performance of zein films as packaging materials that can be accomplished by radiation treatment have been investigated via monitoring of the color, surface density, roughness, mechanical properties (tensile strength and elongation percentage), water uptake, and water barrier properties. The results indicated that gamma-irradiation treatment of the film-forming solution can be used to improve the water barrier properties, as well as color and appearance of the zein films. Moreover, a sterilization effect is considered to be an additional advantage for applying gamma- irradiation.


Asunto(s)
Embalaje de Alimentos/instrumentación , Rayos gamma , Zeína/química , Zeína/efectos de la radiación , Fenómenos Químicos , Color , Luz , Microscopía Electrónica de Rastreo , Permeabilidad , Soluciones , Resistencia a la Tracción , Viscosidad , Agua
10.
J Bone Miner Res ; 20(9): 1680-91, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16059639

RESUMEN

UNLABELLED: In this study, we report that the function of certain mutant VDRs from patients with hereditary HVDRR can at least be partially restored by phosphorylation and hexafluoro 1,25(OH)2D3 analogs. Our study provides new insights into mechanisms involved in enhancement of mutant VDR function. INTRODUCTION: 1,25-Dihydroxyvitamin D-resistant rickets (HVDRR) is a rare genetic disorder caused by inactivating mutations in the vitamin D receptor (VDR). In this study, we examined VDR from patients with HVDRR having mutations in the ligand-binding domain (F251C, I268T, H305Q, E420K). We examined methods of restoring transcriptional activity of these mutants and the mechanisms involved. MATERIALS AND METHODS: Reporter gene transcriptional assays were used to examine the activation of mutant VDRs. Western-blot analysis, glutathione S-transferase (GST) pull-down assays, and chromatin immunoprecipitation (ChIP) assays were also used in this study. RESULTS: Using mutant VDRs, H305Q, F251C, I268T, and 10(-8) M 1,25(OH)2D3, only 10-30% of the activity of wildtype (WT) VDR in activating 24(OH)ase transcription was observed. The transcriptional response of mutant VDR mutants was significantly enhanced 2- to 3-fold by co-treatment of VDR mutant transfected COS-7 cells with 1,25(OH)2D3 and okadaic acid (OA; inhibitor of phosphatase; 50 nM). The H305Q mutant was the most responsive (90% of the response exhibited by WT VDR was restored). The E420K mutant was unresponsive to 1,25(OH)2D3 in the presence or absence of OA. The increased transcriptional response correlated with an increase in the interaction between DRIP205 and the mutant VDR. We further provide evidence that OA induces the phosphorylation of CREB-binding protein (CBP), indicating for the first time a correlation between phosphorylation of CBP and enhanced VDR function. Hexafluoro 1,25(OH)2D3 analogs (RO-26-2198 and RO-4383561) also resulted in at least a partial restoration of the transcriptional responsiveness of mutant VDRs I268T, F251C, and H305Q. Our data indicate that the enhanced potency of the hexafluoro analogs may be caused by increased DRIP205 and glucocorticoid receptor interacting protein 1 (GRIP-1) binding to VDRs and enhanced association of VDRs with DNA, as suggested by results of ChIP assays. CONCLUSION: Our study provides new insights into the mechanisms involved in the enhancement of VDR function by both phosphorylation and hexafluoro analogs and forms a basis for future study of vitamin D analogs or specifically designed kinase activity mediators as potential therapy for the treatment of selected patients with HVDRR.


Asunto(s)
Resistencia a Medicamentos , Mutación , Receptores de Calcitriol/genética , Raquitismo/tratamiento farmacológico , Raquitismo/genética , Vitamina D/análogos & derivados , Animales , Western Blotting , Células COS , Proteínas Portadoras/metabolismo , Línea Celular , Chlorocebus aethiops , Inmunoprecipitación de Cromatina , Relación Dosis-Respuesta a Droga , Electroforesis en Gel de Poliacrilamida , Fibroblastos/metabolismo , Genes Reporteros , Glutatión Transferasa/metabolismo , Ligandos , Subunidad 1 del Complejo Mediador , Ratones , Proteínas del Tejido Nervioso/metabolismo , Ácido Ocadaico/farmacología , Osteoblastos/metabolismo , Fosforilación , Unión Proteica , Estructura Terciaria de Proteína , ARN/metabolismo , ARN Mensajero/metabolismo , Ratas , Proteínas Recombinantes de Fusión/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/farmacología , Transcripción Genética , Transfección , Vitamina D/farmacología
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