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Casting of aluminum with different concentration of alloying elements such as Mg, Mn (similar to that in AA5083) with additional percentages of 0.1, 0.2 and 0.3% Ti, are carried out using graphite crucible. The as-cast microstructure is modified by hot rolling to a thickness of ~ 2 mm. Mechanical and metallurgical and characterization of heat-treated thin sheets are carried out using tensile testing, hardness measurement, metallography, image analysis and optical microscope. By increasing the Ti content, the results show grain refinement and increase in the formation of Al3Ti which reflected positively on the mechanical properties. Specifically, Ultimate tensile strength is increased from 260 MPa (0 wt% Ti) to 345 MPa (0.3 wt% Ti) when using water quenching, 32.6% improvement for air cooling, and 23.3% for furnace cooling. Electrochemical corrosion behavior of heat-treated water quenched, air cooled and furnace cooled samples were tested in 3.5% NaCl solution. The results show that the heat-treated alloys have very good resistance against corrosion, while by increasing the Ti content, the corrosion rate increases due to the grain refinement phenomena.

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This article studied a numerical estimation of the double-diffusive peristaltic flow of a non-Newtonian Sisko nanofluid through a porous medium inside a horizontal symmetric flexible channel under the impact of Joule heating, nonlinear thermal radiation, viscous dissipation, and heat generation/absorption in presence of heat and mass convection, considering effects of the Brownian motion and the thermophoresis coefficients. On the other hand, the long wave approximation was used to transform the nonlinear system of partial differential equations into a nonlinear system of ordinary differential equations which were later solved numerically using the fourth-order Runge-Kutta method with shooting technique using MATLAB package program code. The effects of all physical parameters resulting from this study on the distributions of velocity, temperature, solutal concentration, and nanoparticles volume fraction inside the fluid were studied in addition to a study of the pressure gradients using the 2D and 3D graphs that were made for studying the impact of some parameters on the behavior of the streamlines graphically within the channel with a mention of their physical meaning. Finally, some of the results of this study showed that the effect of Darcy number [Formula: see text] and the magnetic field parameter [Formula: see text] is opposite to the effect of the rotation parameter [Formula: see text] on the velocity distribution whereas, the two parameters nonlinear thermal radiation [Formula: see text] and the ratio temperature [Formula: see text] works on a decrease in the temperature distribution and an increase in both the solutal concentration distribution, and the nanoparticle's volume fraction. Finally, the impact of the rotation parameter [Formula: see text] on the distribution of pressure gradients was positive, but the effect of both Darcy number [Formula: see text] and the magnetic field parameter [Formula: see text] on the same distribution was negative. The results obtained have been compared with the previous results obtained that agreement if the new parameters were neglected and indicate the phenomenon's importance in diverse fields.

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Objective: Several modalities for analgesia after laparoscopic procedures have been used. This study aimed to investigate the efficacy of early versus late bupivacaine/tramadol combination and bupivacaine/dexmedetomidine combination in analgesia for laparoscopic cancer surgeries. Methods: A total of 100 patients of both genders scheduled for elective laparoscopic cancer surgeries were included. Patients were randomly assigned to one of four groups each comprises 25 patients. Group 1: early bupivacaine/tramadol, Group 2: late bupivacaine/tramadol, Group 3: early bupivacaine/dexmedetomidine, and Group 4: late bupivacaine/dexmedetomidine. Early groups received the intraperitoneal instillation before start of surgery and late groups received the instillation after completion of surgery. Perioperative heart rate (HR) and mean arterial blood pressure (MAP) were recorded. The degree of postoperative pain was measured at rest and with cough using Visual analogue scale (VAS) score at 2, 4, 6, 12, 18 and 24 h after surgery. In addition, the total intraoperative fentanyl and postoperative morphine doses were calculated. Results: Both late bupivacaine/tramadol, bupivacaine/dexmedetomidine groups had longer time to receive first analgesic requirement (13.4±3.9, 11.3±3.9 h) respectively as compared to early bupivacaine/tramadol, bupivacaine/dexmedetomidine groups (9.8± 3.6, 8.4± 2.8 h), respectively. Between each early and late group, intraoperative fentanyl consumption was higher for the late groups (75± 22.8, 73± 21.55µg) versus (32.7± 10.9, 37.5± 13.3 µg), respectively. As regards to rescue analgesic requirements, both early bupivacaine/tramadol and bupivacaine/dexmedetomidine groups consumed more analgesics (5.2± 2.0 and 6.1± 1.8 mg) as compared to the late groups (3.2± 0.8 and 4.3± 1.5 mg), respectively. The four groups were comparable for their perioperative HR and MAP values. Conclusion: Intraperitoneal instillation of bupivacaine/tramadol and bupivacaine/dexmedetomidine could be considered an effective route for analgesic administration during laparoscopic cancer surgeries. Early instillation reduced the intraoperative opioid consumption and late instillation resulted in reduced postoperative opioid consumption. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT04813016.

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Production of high-quality maraging steel is dependent not only on the production technology but also on the alloying design and heat treatment. In this work, cobalt-free, low nickel, molybdenum-containing maraging steel was produced by melting the raw materials in a vacuum induction melting furnace and then refining with a shielding gas electroslag remelting unit. The critical transformation temperatures of the investigated steel samples were determined experimentally by differential scanning calorimetry (DSC) analysis and theoretically aiding Thermo-Calc software. Types and chemical composition plus volume fraction and starting precipitation temperature of suggested constituents calculated with the aid of Thermo-Calc software. The microstructures of forged steel specimens that were heat-treated under several conditions were evaluated by X-ray diffraction (XRD), optical microscopy (OP), scanning electron microscopy (SEM), and electron backscattering (EBSD), in addition to transmission electron microscopy (TEM). The mechanical properties of the investigated steel specimens were evaluated by measuring the tensile strength properties and micro-hardness, furthermore, estimating their fracture surface using scanning electron microscopy at lower magnification. The metallographic results show that the microstructure of steel in aged conditions includes high-alloyed martensite and nickel-rich phase, in addition to the low-alloyed-retained-austenite, intermetallic compounds, and lavas-phase (MoCr). Furthermore, TEM and EBSD studies emphasized that the produced steel has high dislocation density with nano-sized precipitate with an average size of ~19 ± 1 nm. Moreover, the metallographic results show that the mentioned microstructure enhances the tensile properties by precipitation strengthening and the TRIP phenomenon. The tensile strength results show that the n-value of investigated steel passes two stages and is comparable with the n-value of TRIP-steel. Steel characterized by 2100 MPa ultimate tensile strength and uniform elongation of more than 7% can be produced by the investigated production routine and optimum heat treatment conditions.

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Brucine, one of the natural medications obtained from Nux vomica seeds, is used as an anti-inflammatory drug. Several investigations were performed to overcome its drawbacks, which will affect significantly its pharmaceutical formulation. The goal of the current investigation was to design, optimize, and evaluate the anti-inflammatory performance of BRU ethosomal gel. Brucineethosomal formulations were prepared using thin film hydration method and optimized by central composite design approach using three independent variables (lecithin concentration, cholesterol concentration, and ethanol percentage) and three response variables (vesicular size, encapsulation efficiency, and skin permeation). The optimized formulation was examined for its stability and then incorporated into HPMC gel to get BRU ethosomal gel. The obtained BRU-loaded ethosomal gel was evaluated for its physical properties, in vitro release, and ex vivo permeation and skin irritation. Finally, carrageenan-induced rat hind paw edema test was adopted for the anti-inflammatory activity. The developed BRU ethosomal gel exhibited good physical characteristics comparable with the conventional developed BRU gel. In vitro release of BRU from ethosomal gel was effectively extended for 6 h. Permeation of BRU from ethosomes was significantly higher than all formulations (p < 0.05), since it recorded steady state transdermal flux value 0.548 ± 0.03 µg/cm2 h with enhancement ratio 2.73 ± 0.23. Eventually, BRU ethosomal gel exhibited potent anti-inflammatory activity as manifested by a significant decrease in rat hind paw inflammation following 24 h. In conclusion, the study emphasized the prospective of ethosomal gel as a fortunate carrier for intensifying the anti-inflammatory effect of Brucine.

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One of the recent advancements in research is the application of natural products in developing newly effective formulations that have few drawbacks and that boost therapeutic effects. The goal of the current exploration is to investigate the effect of jojoba oil in augmenting the anti-inflammatory effect of Brucine natural alkaloid. This is first development of a formulation that applies Brucine and jojoba oil int a PEGylated liposomal emulgel proposed for topical application. Initially, various PEGylated Brucine liposomal formulations were fabricated using a thin-film hydration method. (22) Factorial design was assembled using two factors (egg Phosphatidylcholine and cholesterol concentrations) and three responses (particle size, encapsulation efficiency and in vitro release). The optimized formula was incorporated within jojoba oil emulgel. The PEGylated liposomal emulgel was inspected for its characteristics, in vitro, ex vivo and anti-inflammatory behaviors. Liposomal emulgel showed a pH of 6.63, a spreadability of 48.8 mm and a viscosity of 9310 cP. As much as 40.57% of Brucine was released after 6 h, and drug permeability exhibited a flux of 0.47 µg/cm2·h. Lastly, % of inflammation was lowered to 47.7, which was significant effect compared to other formulations. In conclusion, the anti-inflammatory influence of jojoba oil and Brucine was confirmed, supporting their integration into liposomal emulgel as a potential nanocarrier.

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The present investigation deals with a comprehensive study on the production of aluminum based alloys with the incorporation of different alloying elements and their effect on its electrical conductivity and mechanical properties. Casting of pure aluminum with different concentration and combinations of alloying additives such as cupper (Cu), magnesium (Mg) and silver (Ag) were carried out using a graphite crucible. The as-cast microstructure was modified by hot rolling followed by different heat-treated conditions viz., annealing, normalizing, quenching, and age hardening. The mechanical properties and electrical conductivity of the produced heat-treated alloys sheets under various processing conditions were carried out using tensile testing, hardness, and electrical resistivity measurements. It was found that by increasing the alloying elements content, yield strength results increased significantly by more than 250% and 500% for the as rolled and 8 h aged Al-Cu-Mg alloy, respectively. On the other hand, the electrical conductivity reduces slightly with -14.6% and -16.57% for the as rolled and 8 h aged of the same Al-Cu-Mg alloy, respectively.

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Brucine (BRU) is a natural product derived from nux-vomica seeds. It is commonly used as an anti-inflammatory and anti-nociceptive drug to relieve arthritis and traumatic pain. Nevertheless, its use is significantly limited by its low aqueous solubility, as well as the gastrointestinal problems and systemic toxicity that may occur following oral administration. The goal of this study, therefore, was to formulate and evaluate a nanoemulgel formulation of BRU for enhanced topical anti-inflammatory and anti-nociceptive activities. Different formulations were developed (BRU gel, emulgel and nanoemulgel) using 1% w/w NaCMC as a gelling agent. The formulated preparations were assessed for their physical appearance, spreadability, viscosity, particle size, in vitro drug release and ex vivo permeation studies. In addition, the carrageenan-induced rat hind paw edema method was adopted to scrutinize the anti-inflammatory activity, while the hot plate method and acetic acid-induced writhing test were used to assess the anti-nociceptive activity of different formulations in male BALB/c mice. The formulated BRU-loaded preparations showed good physical characteristics. Cumulative drug release from BRU-loaded nanoemulgel was remarkably higher than that of the other formulations. Ex vivo drug permeation of the nanoemulgel formulation across rat skin showed enhanced drug permeation and higher transdermal flux as compared to BRU-loaded gel or emulgel. Most importantly, the carrageenan-induced rat hind paw edema model verified the efficient anti-inflammatory potential of BRU-loaded nanoemulgel. In addition, BRU-loaded nanoemulgel exhibited significant protective effects against thermal stimulation in the hot plate test and remarkably inhibited acetic acid-induced abdominal writhing in mice. Furthermore, a skin irritation test indicated that BRU-loaded nanoemulgel elicited neither edema nor erythema upon application to rat skin. Collectively, our results suggest that myrrh oil-based nanoemulgel might represent a promising delivery vehicle for potentiating the anti-inflammatory and anti-nociceptive actions of brucine.

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PURPOSE: Chitosan nanoparticles (CS NPs) have been used as a good vehicle for nano-drug delivery due to their good physicochemical properties. Epigallocatechin-3-gallate (EGCG), one of the major active ingredients of green tea, is a natural antioxidant that helps in reducing and preventing cell damage and fighting cancer, plus providing other benefits. The aim of this study is to optimise the preparation parameters in terms of the physical characteristics and stability in CS/EGCG NPs conjugation. RESULTS: The conjugation of CS/EGCGNPs was obtained by means of Poloxamer 188. The average CS/EGCG NPs complex was of size 117.8±38.71nm with a surface charge of +67.8±4.38mV and isoelectric point at pH 7.61. CONCLUSION: In conclusion, NPs produced were stable at 4°C with nanometric size, good polydispersity, good loading and efficiency, envisaging to be a possible candidate for nano-therapeutic delivery system against hepatic fibrosis.

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BACKGROUND: Sepsis-induced diaphragmatic dysfunction is one of the main risk factors of failure to liberate patients from mechanical ventilation. Several studies addressed diaphragmatic ultrasound as a valuable tool in the assessment of diaphragmatic function during liberation from mechanical ventilation in different populations. However, none of these studies examined the use of diaphragmatic ultrasound to predict failure of liberation from mechanical ventilation in subjects with sepsis METHODS: A prospective observational study was done with subjects on mechanical ventilation and with abdominal sepsis. The diaphragmatic thickening fraction, diaphragmatic excursion, and rapid shallow breathing index were assessed 30 min after a spontaneous breathing trial RESULTS: Thirty subjects were enrolled in the study. Seventeen subjects were successfully extubated (56.6%), whereas extubation failed in 13 subjects (43.4%). The time to the first liberation attempt was significantly shorter in the liberation-success group 2.3 (0.7) d compared with the liberation-failure group 5.8 (4.7) d; P = .02. The optimum cutoff value of diaphragmatic thickening fraction for predicting liberation success was ≥30.7%, with a sensitivity of 94.1% and a specificity of 100%. The area under the curve was 0.977. Although diaphragmatic excursion of ≥10.4 mm had a sensitivity of 94% and a specificity of 85% for predicting liberation success, with an area under the curve of 0.85. A rapid shallow breathing index of ≤44 had a specificity of 100% and a sensitivity of 76%; the area under the curve was 0.9. CONCLUSIONS: Diaphragmatic ultrasound indices, namely diaphragmatic thickening fraction and diaphragmatic excursion, could be useful parameters for assessment of success of liberation in patients on mechanical ventilation with abdominal sepsis. (ClinicalTrials.gov registration NCT03094299.).

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OBJECTIVE: An optimized date seed oil (DSO) loaded niosomes was formulated. SIGNIFICANCE: Maximize the extract anti-inflammatory efficacy and govern its release characteristics from nanoparticles for osteoarthritis prevention and treatment purposes. METHODS: By using Box-Behnken Design, the effect of three formulation factors on the entrapment efficiency percentage (Y1), initial DSO release percentage after 2 h (Y2), and cumulative DSO release percentage of DSO after 12 h (Y3), were optimized and studied. The optimized DSO formulation was specified, elaborated, particle size and zeta potential assessed, examined morphologically under electron and light microscope, and in vivo evaluated via carrageenan-induced rat paw edema study. RESULTS: 65.89%, 18.39%, and 58.27% were the measured responses of the optimized niosomes for Y1, Y2, and Y3, respectively. The vesicular structure of the optimized DSO loaded nano-vesicles with nano-size range and good stability features were confirmed. Furthermore, a distinguished anti-inflammatory activity in both prompt and sustained effectiveness were exhibited via the optimized DSO niosomes. Interestingly, the delayed efficacy outcomes of the extract loaded nanoparticles showed a similarity profile as well as the negative control group outcomes. CONCLUSIONS: To emphasize, DSO loading in niosomes revealed a significant enhancement toward inflammation alleviation, which offers a promising implement in osteoarthritis remediation and prohibition.

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New 1-arylamidebiguanide hydrochloride salts were synthesized via reaction of hydrazide derivatives with dicyandiamide in acidic medium. The structure of the obtained derivatives was characterized by spectroscopic and elemental analysis tools. The anti-diabetic properties of the synthesized compounds were determined. Oral treatment of hyperglycemic rats with the synthesized biguanide derivatives showed a significant decrease of the elevated glucose in comparison with the anti-diabetic standard drug, metformin. The effects of the synthesized biguanide derivatives on the diabetic properties regarding liver function enzyme activities (AST, ALT, and ALP), lipid profiles (TC, TG, and TL), lipid peroxide, and nitrous oxide as well as histopathological characteristics were investigated and discussed.

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New 1-substituted-biguanide hydrochloride salts were synthesized via reacting benzo[1,3-d]dioxol-5-amine, phenylhydrazine, N,N-dimethylhydrazinecarboxamide, benzohydrazide and 2-phenyl acetohydrazide with dicyandiamide in acidic medium. Structures of the obtained biguanide salts were characterized by spectroscopic tools. The synthesized compounds were screened for their anti-diabetic activity with standard metformin drug. Oral treatment of hyperglycemic rats with the synthesized biguanide derivatives significantly decreased the elevated blood glucose level. Additionally, anti-diabetic properties towards liver function enzyme activities (AST, ALT and ALP), lipids profiles (TC, TG and TL), lipid peroxide and nitrous oxide as well as histopathological studies relative to metformin hydrochloride were investigated and discussed.

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BACKGROUND/OBJECTIVE: This study was designed to evaluate the potential chemopreventive activities of Ginkgo biloba extract (EGb) and Silybum marianum extract (silymarin) against hepatocarcinogenesis induced by N-nitrosodiethylamine (NDEA) in rats. METHODS: Rats were divided into 6 groups. Group 1 served as normal control rats. Group 2 animals were intragastrically administrated NDEA at a dose of 10 mg/kg five times a week for 12 weeks to induce hepatocellular carcinoma (HCC). Groups 3 and 4 animals were pretreated with silymarin and EGb respectively. Groups 5 and 6 animals were posttreated with silymarin and EGb respectively. The investigated parameters in serum are alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT) and vascular endothelial growth factor (VEGF). The investigated parameters in liver tissue are malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and comet assay parameters. RESULTS: In NDEA group, MDA level was elevated with subsequent decrease in GSH level and SOD, GPx and GR activities. In addition, NDEA group revealed a significant increase in serum ALT, AST and GGT activities and VEGF level. Furthermore, NDEA administrated animals showed a marked increase in comet assay parameters. These biochemical alterations induced by NDEA were confirmed by the histopathological examination of rat livers intoxicated with NDEA that showed an obvious cellular damage and well differentiated HCC.In contrast, silymarin+NDEA treated groups (3&5) and EGb+NDEA treated groups (4&6) showed a significant decrease in MDA level and a significant increase in GSH content and SOD, GPx and GR activities compared to NDEA group. Silymarin and EGb also beneficially down-regulated the increase in serum ALT, AST, GGT activities and VEGF level induced by NDEA. In addition, silymarin and EGb significantly decreased comet assay parameters. Histopathological examination of rat livers treated with either silymarin or EGb exhibited an improvement in the liver architecture compared to NDEA group. CONCLUSIONS: The obtained findings suggested that silymarin and EGb may have beneficial chemopreventive roles against hepatocarcinogenesis through their antioxidant, antiangiogenic and antigenotoxic activities.

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Oxidative stress has been proposed as a possible mechanism involved in lead toxicity. The current study was carried out to evaluate the antioxidant activity of the ethanol extract of Aquilegia vulgaris (L.) against lead acetate (LA)-induced oxidative stress in male rats. Tested animals were treated orally with A. vulgaris extract (100 ppm) in combination with, before, or after LA treatment (20 ppm). The results indicated that the extract alone did not induce any significant changes in body weight gain, food intake, serum biochemical chemistry or the histological picture of the liver and kidney. However, it increased significantly the level of Glutathione (GSH). On the other hand, LA decreased food intake, body weight gain and induced oxidative stress as indicated by the significant changes in serum biochemical parameters and histological picture of liver and kidney and increased lipid peroxide and reduces GSH levels in liver tissues. The extract succeeded to improve the histological pictures of liver and kidney and the biochemical parameters towards the normal values of the control. Moreover, this improvement was pronounced in the animals treated with the extract after LA intoxication.

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The objectives of the present study were (1) to model the effects of process and formulation variables on in vitro release profile of a model drug dyphylline from multi-particulate beads coated with starch acetate (SA); (2) to validate the models using R2 and lack of fit values; (3) to optimize the formulation by response surface methodology (RSM); (4) to characterize the optimized product by thermal, X-ray and infrared spectroscopic analyses. Dyphylline loaded inert beads were coated using organic solution of SA with high degree of substitution. A three-factor, three-level Box-Behnken design was used for the optimization procedure with coating weight gain (X1), plasticizer concentration (X2) and curing temperature (X3) as the independent variables. The regression equation generated for Y5 (cumulative percent drug released after 12 h) was Y5 = 89.83-11.98X1 + 2.82X2 - 4.31X1(2) + 1.90X1X2. Optimization was done by maximizing drug release in 12 h and placing constraints at dissolution time points of 0.5, 1, 4 and 8 h. The drug release data of the optimized product were close to that predicted by the model. The models could explain 99% of variability in responses. Thermal, X-ray and infrared analyses suggested absence of any significant interaction of the drug with the excipients used in the formulation. SEM photographs showed the integrity of the coating layer.

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