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The main focus of this study was on using radiation to make an ultra-absorbent hydrogel (UAH) from sodium alginate (SA) and gelatin (GL) biopolymers. This UAH can effectively handle water and nitrogen in wheat farming during drought stress. The hydrogel was synthesized by gamma irradiation-induced SA/GL/polyacrylamide crosslinking at 10-40 kGy. Varying SA/GL ratios affected swelling and the gel fraction of SA/GL/PAm hydrogels. The (SA/GL 17/83) hydrogel exhibited a 40.03 g/g swelling degree, while increasing SA content resulted in higher swelling, peaking at 75.5 g/g for (SA/GL 83/17). This indicated a synergistic interaction between SA and GL. The gel fraction also increased from 76.8 to 90.3%, with a higher GL content reflecting increased crosslinking. After multiple hydrolysis cycles, the hydrogel achieved 1293 (g/g) swelling and 36 days of water retention. When applied to wheat (Triticuma estivum) under drought stress, it significantly improved shoot length (18%), root length (43%), shoot fresh weight (49%), and shoot dry weight (51%) under extreme drought. The significant increases in protein and carbohydrate content in both shoots (up to 32% and 19%, respectively) and grains (up to 21% and 24%, respectively), along with the reduction in proline content (up to 38%), demonstrate that ultra-absorbent hydrogel (UAH) effectively enhances nitrogen content, photosynthesis, and overall plant health in wheat under varying drought stress levels. This novel SA/GL-based UAH holds promise for addressing water scarcity and agricultural challenges, offering a sustainable solution for water and nitrogen management under drought stress.
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Alginatos , Sequías , Gelatina , Hidrogeles , Nitrógeno , Triticum , Agua , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Triticum/fisiología , Alginatos/química , Gelatina/química , Nitrógeno/metabolismo , Nitrógeno/química , Hidrogeles/química , Agua/química , Estrés Fisiológico , Rayos gammaRESUMEN
The deposition of paraffin on pipelines during crude oil transit and low-temperature restart processes poses a significant challenge for the oil industry. Addressing this issue necessitates the exploration of innovative materials and methods. Pour point depressants (PPDs) emerge as crucial processing aids to modify paraffin crystallization and enhance crude oil flow. This study focuses on the combustion of polyethylene terephthalate (PET) waste, a prevalent plastic, in two distinct oils (castor and jatropha). The resulting black waxy substances (PET/Castor and PET/Jatropha) were introduced in varying weights (1000, 2000, and 3000 ppm) to crude oil. The PET/castor oil combination demonstrated a remarkable reduction in pour point from 18 to -21 °C at 3000 ppm concentration, significantly more effective than PET/jatropha blends. Substantial decreases in viscosity (up to 75%) and shear stress (up to 72%) were also observed for both blends, most prominently at lower temperatures near the pour point. The synergistic effect of PET and oils as nucleating agents that alter crystallization patterns and restrict crystal growth contributes to this enhanced low-temperature flow. This highlights the potential of PET plastic waste as an economical, abundant, and eco-friendly additive to develop high-performance PPDs for crude oil.
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Background: Sickle Cell Disease (SCD) is not a hematologic disease that occurs in isolation; it results in multi-organ complications. There is growing evidence of vascular stiffness as its underlying cause. This study aimed to investigate the relationship between endothelial stiffness and LV dysfunction in SCD patients and to explore its pathophysiology, particularly regarding the depletion of vasodilators such as Nitric Oxide (NO). Methodology: 32 patients with established criteria for SCD and 40 healthy control subjects were selected for this case-control study. Comprehensive clinical assessment and assessment of endothelial function using Brachial Flow-mediated dilation (FMD) were performed, along with serum NO measurement, which was followed by diagnosis and echocardiographic assessment using 3D speckle tracking echocardiography (STE) and tissue Doppler imaging (TDI). Results: Collected SCD cases showed echocardiographic features of Systo-diastolic dysfunction with reduced FMD compared to controls, denoting endothelial dysfunction in those patients. LDH showed a marked elevation, while serum NO showed a significant reduction in cases compared with controls. We also noted a positive correlation between FMD on the one hand and measures of ventricular dysfunction and level of serum NO on the other hand, the latter proving that reduction of NO is responsible for reduced endothelial function. Conclusion: We present the first report to date to outline the role of vascular stiffness as measured by brachial FMD in the induction of left ventricular dysfunction in SCD. We recommend that more research be conducted regarding possible strategies to replenish serum NO stores to delay microvascular injury and, in turn, ventricular dysfunction in SCD.
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Ethylene vinyl acetate (EVA) copolymers are widely employed as pour point depressants to enhance the flow properties of crude oil. However, EVA copolymers have limitations that necessitate their development. This work investigated the modification of EVA via gamma radiation-induced grafting of butyl acrylate (BuA) monomers and the evaluation of grafted EVA as a pour point depressant for crude oil. The successful grafting of poly(butyl acrylate) p(BuA) onto EVA was verified through grafting parameters, FTIR spectroscopy, and 1H NMR spectroscopy. Treating crude oil with 3000 ppm of (EVA)0kGy, (EVA)50kGy, and (1EVA:3BuA)50kGy yielded substantial reductions in pour point of 24, 21, and 21 °C, respectively. Also, rheological characterization demonstrated improving evidenced by a viscosity reduction of 76.20%, 67.70%, and 71.94% at 25 °C, and 83.16%, 74.98%, and 81.53% at 12 °C. At low dosages of 1000 ppm, the EVA-g-p(BuA) exhibited superior pour point reductions compared to unmodified EVA, highlighting the benefit of incorporating p(BuA) side chains. The grafted EVA copolymers with p(BuA) side chains showed excellent potential as crude oil flow improvers by promoting more effective adsorption and co-crystallization with paraffin wax molecules.
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Introduction: Skin injuries represent a prevalent form of physical trauma, necessitating effective therapeutic strategies to expedite the wound healing process. Hesperidin, a bioflavonoid naturally occurring in citrus fruits, exhibits a range of pharmacological attributes, including antimicrobial, antioxidant, anti-inflammatory, anticoagulant, and analgesic properties. The main objective of the study was to formulate a hydrogel with the intention of addressing skin conditions, particularly wound healing. Methods: This research introduces a methodology for the fabrication of a membrane composed of a Polyvinyl alcohol - Sodium Alginate (PVA/A) blend, along with the inclusion of an anti-inflammatory agent, Hesperidin (H), which exhibits promising wound healing capabilities. A uniform layer of a homogeneous solution comprising PVA/A was cast. The process of crosslinking and the enhancement of hydrogel characteristics were achieved through the application of gamma irradiation at a dosage of 30 kGy. The membrane was immersed in a Hesperidin (H) solution, facilitating the permeation and absorption of the drug. The resultant system is designed to deliver H in a controlled and sustained manner, which is crucial for promoting efficient wound healing. The obtained PVA/AH hydrogel was evaluated for cytotoxicity, antioxidant and free radical scavenging activities, anti-inflammatory and membrane stability effect. In addition, its action on oxidative stress, and inflammatory markers was evaluated on BJ-1 human normal skin cell line. Results and Discussion: We determined the effect of radical scavenging activity PVA/A (49 %) and PVA/AH (87%), the inhibition of Human red blood cell membrane hemolysis by PVA/AH (81.97 and 84.34 %), hypotonicity (83.68 and 76.48 %) and protein denaturation (83.17 and 85.8 %) as compared to 250 µg/ml diclofenac (Dic.) and aspirin (Asp.), respectively. Furthermore, gene expression analysis revealed an increased expression of genes associated with anti-oxidant and anti-inflammatory properties and downregulated TNFα, NFκB, iNOS, and COX2 by 67, 52, 58 and 60%, respectively, by PVA/AH hydrogel compared to LPS-stimulated BJ-1 cells. The advantages associated with Hesperidin can be ascribed to its antioxidant and anti-inflammatory attributes. The incorporation of Hesperidin into hydrogels offers promise for the development of a novel, secure, and efficient strategy for wound healing. This innovative approach holds potential as a solution for wound healing, capitalizing on the collaborative qualities of PVA/AH and gamma irradiation, which can be combined to establish a drug delivery platform for Hesperidin.
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Alginatos , Hesperidina , Hidrogeles , FN-kappa B , Alcohol Polivinílico , Factor de Necrosis Tumoral alfa , Hesperidina/farmacología , Hesperidina/química , Alcohol Polivinílico/química , Humanos , Alginatos/química , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Hidrogeles/química , Transducción de Señal/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Cicatrización de Heridas/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Antioxidantes/farmacología , Antioxidantes/química , Inflamación/tratamiento farmacológicoRESUMEN
BACKGROUND: Congenital portosystemic shunt (CPSS) is a vascular malformation in which portal blood drains toward the systemic circulation, leading to pulmonary hypertension. CASE PRESENTATION: A 10-year-old patient was brought for evaluation because of dyspnea on exertion. Echocardiography revealed a pulmonary hypertension of 75 mmHg, and multi-slice CT angiography revealed the presence of a CPSS. Closure was finally implemented using a muscular ventricular septal defect device. Follow-up of the patient revealed a gradual decline in pulmonary hypertension. CONCLUSIONS: CPSS is an overlooked cause of reversible pulmonary hypertension (PH). Closure of such lesions and reversal pulmonary hypertension are possible via catheterization. The preferred device type depends largely on the intervening team. Plugs are the first choice for interventional radiologists, while ventricular and atrial septal occluder devices and duct occluders are preferred by pediatric cardiologists.
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Nowadays, many researchers aim to fill polymer materials with inorganic nanoparticles to enhance the polymer properties and gain the merits of the polymeric host matrix. Sol-gel synthesized Co3O4 nanoparticles are subjected to different doses of electron beam (10, 20, and 30 kGy) to study their physiochemical properties and choose the optimized nanoparticles to fill our polymeric matrix. Crosslinked polyethylene (XLPE) has been filled with 5 wt % of un-irradiated cobalt oxide nanoparticles using the melt extruder method. The structural, optical, magnetic, and electrical properties of the XLPE/Co3O4 nanocomposite before and after exposure to different doses of electron beam radiation have been characterized. The crystallite size of face-centered cubic spinel Co3O4 nanoparticles has been confirmed by XRD whereas and their unique truncated octahedral shape obviously appears in SEM micrographs. The crystallite size of Co3O4 nanoparticles has decreased from 47.5 to 31.5 nm upon irradiation at a dose of 30 kGy, and significantly decreased to 18.5 nm upon filling inside XLPE matrix. Related to the oxidation effect of the electron beam, the Co2+/Co3+ ratio on the surface of Co3O4 nanoparticles has decreased upon irradiation as verified by XPS technique. This consequently caused the partial elimination of oxygen vacancies, mainly responsible for the weak ferromagnetic behavior of Co3O4 in its nanoscale. This appears as decreased saturation magnetization as depicted by VSM. The XLPE/Co3O4 nanocomposite has also shown weak ferromagnetic behavior but the coercive field (Hc) has increased from 112.57 to 175.72 G upon filling inside XLPE matrix and decreased to 135.18 G after irradiating the nanocomposite at a dose of 30 kGy. The ionic conductivity of XLPE has increased from 0.133 × 10-7 to 2.198 × 10-3 S/cm upon filling with Co3O4 nanoparticles while a slight increase is observed upon irradiation.
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The newest method for recycling waste linear low-density polyethylene (LLDPE) is the thermo-catalytic degradation technique known as catalytic pyrolysis. Typically, it is limited by 500-800 °C high temperatures. Catalytic pyrolysis releases toxins and forms harmful carbonized char. The current study is based on exposing wasted LLDPE to different gamma irradiation doses and then pyrolysis in castor oil (150-300 °C). The output product of Ir-(rLLDPE) is turned into another compound with a new structural architecture (sponge-like). SEM analysis confirms conversion, showing sponge-like spicules and layers. Ir-(rLLDPE) is sponge-like with a soft, malleable, absorbent texture. The DSC demonstrates altered thermal properties, with a melting point at 121 °C splitting into two peaks (endothermic at 117 °C and exothermic at 160 °C). The exothermic peaks signify the curing process of the sponge-like material. Ir-(rLLDPE) is assessed as an adsorbent for aqueous oils and solvents. The study examines irradiation doses, pyrolysis temperature, and time on adsorbent capacity. The oil removal obeys the Langmuir isotherm with monolayer adsorption, with a maximum adsorption capacity of 24.75 g/g of waste oil and 43 g/g of 1,1,2,2-tetrachloroethane. Squashing maintains adsorption after 20 reuses. Data shows sponges effectively clean marine oil spills and solvents.
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BACKGROUND: Hemodialysis (HD) success is dependent mainly on vascular access (VA). The aim of this study is to share the experience of Pediatric Nephrology Unit (PNU), Cairo University Children's Hospital (CUCH), with VA-related obstacles in end stage kidney disease (ESKD) HD children. METHODS: This is a retrospective analysis of VA related data of 187 ESKD children received regular HD over 3 year duration (2019-2021). Kaplan-Meier curves were used to present arteriovenous fistula (AVF) and cuffed catheters survivals. RESULTS: Uncuffed central venous catheter (CVC) was the primary VA for HD in up to 97.3% with 2.7% of patients had AVF performed and attained maturation before initiation of regular HD. Fifty-six (29.9%) patients have inserted 120 tunneled CVCs. AVFs & AV grafts (AVF) were performed in 79 (42.2%) and 6 (3.2%) patients respectively. There were 112 uncuffed CVCs implanted beneath the screen in Rt internal jugular vein (IJV) (44%) Lt IJV (17%), right internal mammary vein (2.7%) while Trans hepatic (TH) technique was used to place 39 uncuffed CVCs (34%) in the inferior vena cava (IVC). Catheter-related bacteremia (CRB) was the most frequent complication in uncuffed and cuffed CVCs (2.58 / 100 catheters day and 10.1 /1000 catheter days respectively). AVFs achieved a high success rate (83%) after 757.71 ± 512.3 functioning days. CONCLUSION: Native AVF is the preferred VA for pediatric HD but its creation is limited by the small sized vessels where non-cuffed CVC could be a reasonable relatively long-term alternative. Challenging situations (occluded central veins) could benefit from TH technique of CVC insertion in IVC.
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Bacteriemia , Fallo Renal Crónico , Humanos , Niño , Estudios Retrospectivos , Diálisis Renal , Fallo Renal Crónico/terapia , CatéteresRESUMEN
Nanocomposite hydrogel biomaterials represent an exciting Frontier in biomedicine, offering solutions to longstanding challenges. These hydrogels are derived from various biopolymers, including fibrin, silk fibroin, collagen, keratin, gelatin, chitosan, hyaluronic acid, alginate, carrageenan, and cellulose. While these biopolymers possess inherent biocompatibility and renewability, they often suffer from poor mechanical properties and rapid degradation. Researchers have integrated biopolymers such as cellulose, starch, and chitosan into hydrogel matrices to overcome these limitations, resulting in nanocomposite hydrogels. These innovative materials exhibit enhanced mechanical strength, improved biocompatibility, and the ability to finely tune drug release profiles. The marriage of nanotechnology and hydrogel chemistry empowers precise control over these materials' physical and chemical properties, making them ideal for tissue engineering, drug delivery, wound healing, and biosensing applications. Recent advancements in the design, fabrication, and characterization of biopolymer-based nanocomposite hydrogels have showcased their potential to transform biomedicine. Researchers are employing strategic approaches for integrating biopolymer nanoparticles, exploring how nanoparticle properties impact hydrogel performance, and utilizing various characterization techniques to evaluate structure and functionality. Moreover, the diverse biomedical applications of these nanocomposite hydrogels hold promise for improving patient outcomes and addressing unmet clinical needs.
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Fluoride and aluminum are ubiquitous toxic metals with adverse reproductive effects. The citrus flavonoid hesperidin has protective activities but poor solubility and bioavailability. Nanoparticulate delivery systems can improve flavonoid effectiveness. We conducted this study to prepare a pH-responsive chitosan-based nanogel for hesperidin delivery and evaluate its effectiveness against sodium fluoride (NaF) and aluminum chloride (AlCl3) induced testicular toxicity in mice. The nanogel was synthesized using 2 kGy gamma irradiation, enabling a size under 200 nm and enhanced hesperidin release at pH 6 matching testicular acidity. Male mice received 200 mg/kg AlCl3 and 10 mg/kg NaF daily for 30 days. Hesperidin nanogel at 20 mg/kg was administered orally either prophylactically (pretreatment) or after intoxication (posttreatment). The results showed that AlCl3 + NaF induced severe oxidative stress, hormonal disturbance, apoptosis, and endoplasmic reticulum stress, evidenced by significant changes in the studied parameters and testicular histological damage. Hesperidin nanogel administration significantly inhibited oxidative stress markers, restored luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone levels, and alleviated tissue damage compared to the intoxicated group. It also downregulated the expression level of pro-apoptotic genes Bax, caspase-3, caspase-9, and P38MAPK, while upregulating the expression level of the anti-apoptotic BCL2 gene. Endoplasmic reticulum stress sensors PERK, ATF6, and IRE-α were also downregulated by the nanogel. The chitosan-based nanogel enhanced the delivery and efficacy of poorly bioavailable hesperidin, exhibiting remarkable protective effects against AlCl3 and NaF reproductive toxicity. This innovative nanosystem represents a promising approach to harnessing bioactive phytochemicals with delivery challenges, enabling protective effects against chemical-induced testicular damage.
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The research focuses on utilizing gamma irradiation to synthesize polyacrylic acid-co-polyacrylamide p(AAm-co-AAc) hydrogels. The effect of synthetic parameters on physicochemical features of p(AAm-co-AAc) hydrogls were examined, including acrylic acid (AAc): acrylamide (AAm) weight ratios, monomer concentration, and gamma irradiation dosage (kGy). At the optimum synthetic conditions (30 kGy and 75% AAc), different chemical modifications are explored to incorporate sulfonate, hydroxyl, carboxyl, cysteine, thiol, and amine functional groups within the bare hydrogel (Cpd 0) structure. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses confirmed the success development of functionalized hydrogels (namely Cpd 1 to 6) with three-dimensional porous structures. These modified hydrogels include Cpd 1, a sulfonated hydrogel through a sulfonation reaction; Cpd 2, modified via NaOH hydrolysis; Cpd 3, modified using thionyl chloride; Cpd 4, incorporating cysteine modification through reaction with cysteine; Cpd 5, with 4-(Dimethylamino) benzaldehyde; and Cpd 6, modified with 3,4-Dimethylbenzoic acid.The effect of hydrogel composition and surface functionalities on the swelling capacity and interactions with scale-forming/heavy metal ions (e.g., Ba2+, Sr2+, and Cu2+) was investigated in saline water solution (NaCl = 1000 mg/L). Batch adsorption studies reveal that all modified hydrogels exhibited higher removal efficiency for the three metal ions than unmodified p(AAm-co-AAc) hydrogel, validating the key role of surface functionalities in tailoring hydrogel affinity for metal ions adsorption. Amongst these, NaOH-treated hydrogel (Cpd 2) outperformed all other modified ones in the removal of Cu2+, Ba2+, and Sr2+ ions, with maximum capacities of 13.67, 36.4, and 27.31 mg/g, respectively. Based on adsorption isotherm and kinetic modeling, the adsorption process of the three metal ions onto all modified hydrogels better obeyed Freundlich isotherm and pseudo-first-order kinetic models. Thermodynamic studies also indicated that the adsorption behavior of Sr2+ ions can exhibit both exothermic and endothermic characteristics, depending on the nature of hydrogel surface chemistry. Conversely, the adsorption process of Cu2+ and Ba2+ ions onto all modified hydrogels is endothermic, suggesting favorable chemical adsorption mechanisms. These findings reveal that the specific adsorption performance of hydrogel is dependent on the type of modification and the targeted heavy metal ions. Based on the nature of hydrogel surface functionality, surface modifications can change the charge density, hydrophilicity, and overall chemical environment of the hydrogel, offering a versatile approach to optimize the adsorption affinity/selectivity of hydrogel's in removing scale-forming/heavy metals from water solutions.
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The optical features of gold nanorods (GNR) may be precisely controlled by manipulating their size, shape, and aspect ratio. This review explores the impact of these parameters on the optical tuning of (GNR). By altering the experimental conditions, like the addition of silver ions during the seed-mediated growth process, the aspect ratio of (GNR) may be regulated. The shape is trans from spherical to rod-like structures resulting in noticeable changes in the nanoparticles surface plasmons resonance (SPR) bands. The longitudinal SPR band, associated with electron oscillations along the long axis, exhibits a pronounced red shift into the (NIR) region as the aspect ratio increases. In contrast, the transverse SPR band remains relate unchanged. Using computational methods like the discrete dipole approximation (DDA) allows for analyzing absorption, scattering, and total extinction features of gold (G) nanoparticles. Studies have shown that increasing the aspect ratio enhances the scattering efficiency, indicating a higher scattering quantum yield (QY). These findings highlight the importance of size, shape, and aspect ratio in controlling the optical features of (GNR) providing valuable insights for various uses in nanophotonics and plasmonic-dependent fluorescence in cancer treatment and developing new photonic compound NRs.
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Marine biofouling, undesirable growth of organisms on submerged surfaces, poses significant challenges in various industries and marine applications. The development of environmentally safe antifouling coatings employing nano-MnO2/cellulose nanofiber (CNF) composite with bisphenol A epoxy diacrylate/glycidyl methacrylate (BED/GMA) irradiated by electron beam (T1) has been achieved in the current work. The physico-chemical characteristics of the fabricated coatings have been studied using Fourier transforms infrared spectroscopy, scanning electron microscope, water contact angle, and X-ray diffraction. The efficacy of T1 formulation and pure BED/GMA polymer (T2) in inhibiting biofouling formation was investigated in seawater of Alexandria Eastern Harbour by examining biofilm development morphologically and biochemically. In addition, regular analyses of seawater physicochemical parameters were conducted monthly throughout study. Results provide valuable information on coating performance as well as the complex interactions between coatings, biofilms, and environmental factors. The T1 formulation exhibited strong anti-fouling and anticorrosion properties over 2 months. However, after four months of immersion, all coated steel surfaces, including T1, T2, and T0, were heavily covered with macro-fouling, including tubeworms, barnacles, and algae. Biochemical analysis of extracellular polymeric substances (EPS) showed statistically significant variations in carbohydrates content between the coated surfaces. The T1 formulation showed decreased protein and carbohydrate content in EPS fractions after 14 days of immersion indicating less biofouling. Moreover, elemental analysis showed that carbon, oxygen, and iron were the predominant elements in the biofilm. Other elements such as sodium, silicon, chloride, and calcium were in lower concentrations. T2 and T0 surfaces revealed higher calcium levels and the appearance of sulphur peaks if compared with T1 surface. Diatoms and bacteria were detected on T1, T2, and T0 surfaces. The observed warming of seawater and nutrient-rich conditions were found to promote the growth of fouling organisms, emphasizing the importance of considering environmental factors in biofouling management strategies.
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Incrustaciones Biológicas , Nanofibras , Incrustaciones Biológicas/prevención & control , Celulosa , Calcio , Electrones , Biopelículas , Propiedades de SuperficieRESUMEN
In this study, the development of advanced materials for the removal of oil-water pollution was explored, with a focus on environmental protection. The primary novelty of this research involved the conversion of waste Linear low-density polyethylene (LLDPE) into a sponge-like material denoted as sLLDPE. The process of converting involved thermal treatment in castor oil, resulting in the creation of a porous structure within the material. This sLLDPE material exhibited remarkable oil adsorbent properties and demonstrated enhanced performance in the removal of various organic contaminants from both aqueous and oil-based systems. Furthermore, gamma irradiation-induced crosslinking reactions were implemented within a dose range of 0 up to 90 kGy to further improve its oil removal capabilities. Comparing samples subjected to a radiation dose of 50 kGy with those receiving no irradiation (0 kGy), it was observed that the maximum adsorption capacities for various oils, including crude oil, gasoline oil, motor oil, pump oil, and waste oil, increased significantly. Specifically, the adsorption capacities increased by approximately 216.2%, 235.3%, 24.1%, 111.5%, and 18.6% for the respective oils. It rapidly separated oil-water mixtures with ~ 100% efficiency in a column system and maintained performance over 20 reuse cycles. The converted sLLDPE sponge exhibited excellent organics removal across solvents. The findings of this study not only shed light on the impact of irradiation on polymeric materials but also contribute to our understanding of their potential applications in environmental cleanup processes.
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Introducing dental polymers has accelerated biotechnological research, advancing tissue engineering, biomaterials development, and drug delivery. Polymers have been utilized effectively in dentistry to build dentures and orthodontic equipment and are key components in the composition of numerous restorative materials. Furthermore, dental polymers have the potential to be employed for medication administration and tissue regeneration. To analyze the influence of polymer-based investigations on practical medical trials, it is required to evaluate the research undertaken in this sector. The present review aims to gather evidence on polymer applications in dental, oral, and maxillofacial reconstruction.
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Materiales Biocompatibles , Ingeniería de Tejidos , Materiales Biocompatibles/farmacología , Sistemas de Liberación de Medicamentos , PolímerosRESUMEN
The global threat of infectious diseases and antibiotic resistance calls for the development of potent antimicrobial agents integrated with hydrogel for effective control and treatment. Hydrogel is advanced biomaterials compounds. Hydrogel is an advanced biomaterial compound that offers tunable physical and chemical properties, which can be tailored to specific biomedical applications. This study investigates the antibacterial properties of pectin/polyethylene oxide (PEC/PEO)-based poly acrylamide hydrogels containing 5 wt% nano-metal oxides (TiO2, CaO, MgO, and ZnO) synthesized through gamma irradiation at a dose of 30 kGy. This technique allows for sterilization and effectively incorporating the metal oxide nanoparticles within the hydrogel matrix. Characterization of the nanocomposites is performed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Incorporating metal oxide nanoparticles induces noticeable changes in the FTIR spectra, confirming interactions between the nanoparticles and the hydrogel matrix. The antibacterial activity of the nanocomposites is evaluated against different bacteria, and the results demonstrate significant inhibitory effects, especially for MgO- and ZnO-hydrogel nanocomposites against P. mirabilis, S. aureus, P. aeruginosa, and C. albicans, highlighting their potential as antimicrobial agents. The 5 wt% of MgO, ZnO, TiO2 and CaO inside PEO/PEC-co-AAm hydrogel nanocomposites exhibited significant inhibitory effects, with a respective optical density at λ = 600 nm (OD600) values of 0.896 nm, 0.986 nm, 1.250 nm, and 1.980 nm compared to the control and hydrogel alone (OD600 values of 2.88 nm and 2.72 nm, respectively). The antibacterial activity of the (MgO-, ZnO-, TiO2-, and CaO-hydrogel) was enhanced, resulting in the inhibition of S. aureus growth by approximately 68.89 %, 65.86 %, 56.25 %, and 31.94 %, respectively. Incorporating nanoparticles into a hydrogel matrix introduces novelty by preventing their aggregation and synergistically enhancing the antibacterial activity. The hydrogel's porous structure and water content facilitate the physical entrapment of bacteria and promote proximity to the metal oxide nanoparticles, resulting in improved interaction and antimicrobial effectiveness. Moreover, the hydrogel ability to absorb and entrap resistance compounds released by bacteria, coupled with its ability to supply water for the generation of reactive oxygen species, further contributes to its antimicrobial properties.
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Nanopartículas del Metal , Nanocompuestos , Óxido de Zinc , Hidrogeles/farmacología , Hidrogeles/química , Óxido de Zinc/farmacología , Óxido de Zinc/química , Óxido de Magnesio/farmacología , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química , Óxidos/farmacología , Materiales Biocompatibles/farmacología , Nanopartículas del Metal/química , Bacterias , Agua/farmacología , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Nanocompuestos/químicaRESUMEN
The study addresses the potential negative impacts of climate change on water resources, specifically irrigation water for crops. The radiation technique produces the biomaterial hydrogel as a soil conditioner by polymerizing hydroxy ethyl cellulose/acrylamide (HEC/AAm) at various irradiation doses and copolymer concentrations. A maximum swelling of 23.4 g/g is attained by (HEC/PAAm) hydrogel at 1/7.5 ratio, prepared by 10 kGy gamma irradiation. The study introduces a new class of ultra-absorbent hydrogel (UAH) to address the low swelling limitation for soil conditioner applications. The alkaline hydrolysis treatments with NaOH, LiOH, and KOH enhance the water absorbency of (HEC/PAAm) hydrogel, with the highest capacity of 1220 g/g achieved by the KOH treatment, surpassing NaOH (622 g/g) and LiOH (540 g/g). The cumulative release of fertilizers from the UAH sample shows a slow and controlled release behavior. Urea takes 22 days to reach 100 % release. The UAH demonstrates water retention for 28 days, improving the growth of Zea mays L. at drought stress levels of 0 %, 25 %, 50 %, and 100 %, revealing an increase in shoot length by 16 %, 19 %, 24 %, and 20 %, respectively. Also, UAH increased the contents of chlorophyll a, b, a + b, and carotenoid on maize plant leaves compared to the control sample.
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Fertilizantes , Hidrogeles , Fertilizantes/análisis , Zea mays , Sequías , Clorofila A , Hidróxido de Sodio , Suelo , AguaRESUMEN
The use of 5-fluorouracil (5-FU) is associated with multifaceted challenges and poor pharmacokinetics. Accordingly, our study was designed to prepare 5-FU nanogel as a new form of the colon cancer chemotherapeutic drug 5-FU using polyacrylic acid and gelatin hybrid nanogel as efficient drug carriers. Alongside the in vivo chemotherapeutic evaluation, the anti-proliferative and anti-apoptotic efficacy were carried out for 5-FU nanogel against 1,2-dimethylhydrazine (DMH, 20 mg/kg) and γ-radiation (4 Gy)-prompted colon dysplasia in rats compared to 5-FU. The morphology and size of 5-FU nanogel were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS) in addition to cytotoxicity assay. The expression of phosphoinositide-3-kinase (PI3K)/Akt, mammalian target of rapamycin (mTOR); Toll-like receptor2 (TLR2)/nuclear factor kappa B), adenosine monophosphate (AMP)-activated protein kinase (AMPK) and its downstream autophagy-related genes in addition to apoptotic markers were measured in colon tissues. Results: 5-FU nanogel reduced the levels of the TLR2/ NF-κß as well as the expression of PI3K/AKT/mTOR. Moreover, it promoted autophagy through the activation of the AMPK and its downstream targets which consequently augmented the intrinsic and extrinsic apoptotic pathways. Conclusion: Collectively, these data might strengthen the therapeutic potential of 5-FU nanogel which can be used as an antitumor product for colon cancer.
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Aerogel is a high-performance thermal resistance material desired for high-temperature applications like dye-sensitized solar cells, batteries, and fuel cells. To increase the energy efficiency of batteries, an aerogel is required to reduce the energy loss arising from the exothermal reaction. This paper synthesized a different composition of inorganic-organic hybrid material by growing the silica aerogel inside a polyacrylamide (PAAm) hydrogel. The hybrid PaaS/silica aerogel was synthesized using different irradiation doses of gamma rays (10-60 kGy) and different solid contents of PAAm (6.25, 9.37, 12.5, and 30 wt %). Here, PAAm is used as an aerogel formation template and carbon precursor after the carbonization process at a temperature of (150, 350, and 1100 °C). The hybrid PAAm/silica aerogel was converted into aluminum/silicate aerogels after soaking in a solution of AlCl3. Then, the carbonization process takes place at a temperature of (150, 350, and 1100 °C) for 2 h to provide C/Al/Si aerogels with a density of around 0.18-0.040 gm/cm3 and porosity of 84-95%. The hybrid C/Al/Si aerogels presented interconnected networks of porous structures with different pore sizes depending on the carbon and PAAm contents. The sample with a solid content of 30% PAAm in the C/Al/Si aerogel was composed of interconnected fibrils whose diameter was about 50 µm. The structure after carbonization at 350 and 1100 °C was a condensed opening porous 3D network structure. This sample gives the optimum thermal resistance and a very low thermal conductivity of 0.073 (w/m·k) at low carbon content (2.71% at temperature 1100 °C) and high vpore (95%) compared with carbon content 42.38% and vpore (93%) which give 0.102 (w/m·k). This is because at 1100 °C, the carbon atoms evolve to leave an area between Al/Si aerogel particles, increasing the pore size. Furthermore, the Al/Si aerogel had excellent removal ability for various oil samples.