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Salvadora persica extract attenuates cyclophosphamide-induced hepatorenal damage by modulating oxidative stress, inflammation and apoptosis in rats

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Journal of Integrative Medicine 2022年第4期20卷 348-354页

作者： Talat Albukhari Bassem Refaat el-sayed Bakr Sameh Baz Bodour Rajab Hossam Gadalla mohamed el-boshy Department of Immunology and Hematology Faculty of MedicineUmm Al-Qura UniversityMakkah 21955Saudi Arabia Department of Laboratory Medicine Faculty of Applied Medical SciencesUmm Al-Qura UniversityMakkah 7607Saudi Arabia Clinical Nutrition Department Faculty of Applied Medical Sciences Umm Al-Qura UniversityMakkah 7607Soudi Arabia Clinical Pathology Department Faculty of Veterinary MedicineMansoura UniversityMansoura 35516Egypt

Objective: Salvadora persica(SP) is used as a food additive and is a common ingredient in folk *** study investigates the antioxidant, anti-inflammatory, and beneficial effects of SP against cyclophosphamide(CYP) toxicity in ***: In a 10-day study, 32 male rats were equally allocated into 4 groups(8 rats/group) as follows:the normal control(NC group), normal rats that only received oral aqueous extract of SP(100 mg/[kg·d];SP group), animals treated with intraperitoneal CYP injections(30 mg/[kg·d];CYP group), and the CYP + SP group that concurrently received CYP with SP aqueous extract. Serum samples were collected to measure the liver and renal biochemical profiles, as well as antioxidant and oxidative stress markers and the concentrations of interleukin-1β(IL-1β), IL-6, IL-10, tumor necrosis factor-a(TNF-a), nuclear factor-κB(NF-κB) and adenosine 5’-monophosphate-activated protein kinase(AMPK). Hepatic and renal tissues were also harvested for histopathology and to measure apoptosis using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling technique, alongside tissue levels of oxidative stress ***: Liver enzymes, total bilirubin, creatinine and urea, as well as serum IL-1β, IL-6, TNF-a and NF-κB increased significantly, whilst total protein, albumin, calcium, IL-10 and AMPK declined in serum of the CYP group relative to the NC group. The hepatorenal concentrations of glutathione, glutathione peroxidase and catalase declined markedly in the CYP group, whereas malondialdehyde, protein adducts, and apoptosis index increased compared with the NC group. By contrast, the hepatorenal biochemistry and apoptosis index of the SP group were comparable to the NC group. Interestingly, the CYP + SP group had significant improvements in the liver and renal biochemical parameters, enhanced anti-oxidative and anti-inflammatory effects, and marked declines in hepatic and renal apoptosis relative to the CYP group. Moreover, all mon

关键词： Cyclophosphamide Salvadora persica Cytokine NF-κB AMP-activated protein kinases Antioxidants Anti-inflammatory agents

Effects of Nickel Distribution on the Strengthening and Toughening of Alumina Ceramics

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Journal of Materials Science & Technology 2008年第5期24卷 723-728页

作者： mohamed.M.el-sayed Seleman Department of Materials and Metallurgical Eng. Faculty of Petroleum and Mining Eng.Post Code 43721SuezEgypt

Three types of composite materials were designed and fabricated by hot pressing powder blends of alumina with 20 vol. pct nickel particles. The composites differ in the shape, size and distribution of the nickel particles. Composite microstructures are described and measurements of density, hardness, flexure strength, and fracture toughness are reported. The results showed that the fracture strength of the composite with dispersed nickel particles is higher than the other two composites （network microstructure and mixed microstructure） and the alumina matrix. For all the composites studied, tougher materials than the monolithic alumina were produced. The fracture toughness of the composite with a network microstructure is much higher than that of the other composites. The toughening mechanisms were described based on the observation of the fracture surfaces and the crack-particle interactions. Moreover, the parameters for microstructural tailoring of these materials have been deduced. The toughening of the produced composites was explained in light of the interracial bond strength.

关键词： Alumina-nickel composites Nickel morphology Interfacial bonding Fracturetoughness Flexure strength

Processing of Ceramic Based Nanocomposite Usingα-Al_2O_3 Powder and FeCl_2 Solution as Starting Materials

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Journal of Materials Science & Technology 2007年第6期23卷 837-842页

作者： mohamed M.el-sayed Seleman Department of Materials and Metallurgical Engineering Faculty of Petroleum and Mining EngineeringPost Code 43721SuezEgypt

Alumina-iron nanocomposite powders were prepared by a two-step process. In the first step, α-Al2O3-FeCl2 powder mixture was formed by mixing α-Al2O3 powders with FeCl2 solution followed by drying. In the second step, the FeCl2 in the dry power mixture was selectively reduced to iron particles. A reduction temperature of 750℃ for 15 min in dry H2 was chosen based on the thermodynamic calculations. The concentration of iron in FeCl2 solution was calculated to be 20 vol. pct in the final composite. Two techniques were used to produce composite bulk materials. The Al2O3 nanocomposite powders were divided to two batches. The first batch of the produced mixture was hot pressed at 1400℃ and 27 MPa for 30 min in a graphite die. To study the effect of oxygen on the Al2O3/Fe interface bonding and mechanical properties of the composite, the second batch was heat treated in air at 700℃ for 20 min to partially oxidize the iron particles before hot pressing. Characterization of the composites was undertaken by conventional density measurements, X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and electron probe micro analysis （EPMA）. The suggested processing route （mixing, reduction and hot pressing） produces ceramic-metal nanocomposite much tougher than the pure Al2O3. The fracture strength of the produced Al2O3/Fe nanocomposite is nearly twice that of the pure Al2O3. The presence of spinel phase, FeAl204, as thick layer around the Fe particles in the Al2O3 matrix has a detrimental effect on interfacial bonding between Fe and AI203 and the fracture properties of the composite.

关键词： Ferrous chloride Reduction Alumina-iron nanocomposite Spinel phase

Toxoplasma gondii infection can induce retinal DNA damage: an experimental study

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 431-436页

作者： Nagwa Mostafa el-sayed Eman mohamed Aly Department of Medical Parasitology Research Institute of Ophthalmology Department of Basic Science Biophysics and Laser Science Unit Research Institute of Ophthalmology

AIM:To detect whether Toxoplasma gondii(***)infection of mice can induce retinal DNA ***:A total of 20 laboratory-bred male Swiss albino mice were used and divided into four groups:control group(non-infected animals);*** infected group;immunosuppressed infected group;and infected group treated with sulfadiazine and *** eyes were collected 6wk post infection and retinas were *** retina was immediately processed for comet assay and the frequency of tailed nuclei(DNA damage)was *** addition,retinal DNA damage was revealed by various comet assay parameters that were provided by the image analysis software including tail length,percentage of DNA in the tail,percentage of tailed cells and tail ***:The obtained results showed that *** infection induced a statistically significant increase in the frequency of tailed nuclei,tail length,percentage of DNA in the tail,and tail moment in mice retinal cells compared to the control group(which showed some degree of DNA damage).In immunosuppressed infected group,retinal DNA damage was severing and there was significant increase in various comet assay parameters compared to both control and infected *** treatment with sulfadiazine and pyrimethamine,retinal DNA damage decreased and all comet assay parameters showed a statistical significant decrease compared to infected ***:*** infection can induce DNA damage in mice retinal cells.

关键词： Toxoplasma gondii retinochoroiditis DNA damage comet assay

Microstructure and mechanical properties of hot extruded 6016 aluminum alloy/graphite composites

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Journal of Materials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed M.el-sayed Seleman mohamed M.Z.Ahmed Sabbah Ataya Department of Metallurgical and Materials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai Metallurgical and Materials Research Center of Scientific Excellence (SSMMR-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Department of Mechanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 aluminum alloy matrix to fabricate metal/ceramic composites is still a great challenge and various parameters should be considered. In this study, dense AA6016 aluminum alloy/（0-20 wt%） graphite composites have successfully been fabricated by powder metallurgy process. At first, the mixed aluminum and graphite powders were cold compacted at 200 MPa and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceramic phases（free graphite and in-situ formed carbides） on microstructure, physical and mechanical properties of the produced composites were finally investigated. The results show that the fabricated composites have a relative density of over 98%. SEM observations indicate that the graphite has a good dispersion in the alloy matrix even at high graphite content. Hardness of all the produced composites was higher than that of aluminum alloy matrix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultimate tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite composites were determined by high precision second order equations. Both compressive and ultimate tensile strengths have been correlated to microstructure constituents with focusing on the in-situ formed ceramic phases, silicon carbide（SiC） and aluminum carbide（Al4 C3）. The ductile fracture mode of the produced composites became less dominant with increasing free graphite content and in-situ formed carbides. Wear resistance of Al/graphite composites was increased with increasing graphite content. Aluminum/20 wt% graphite composite exhibited superior wear resistance over that of AA6016 aluminum alloy.

关键词： AA6016/graphite composites Hot extrusion In-situ carbides Mechanical properties Wear resistance Fracture behavior

Cuticular hydrocarbons in two parapatric species of ants and their hybrid

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Integrative Zoology 2011年第3期6卷 259-265页

作者： mohamed el-SHEHABY mohamed sayed SALAMA elisabeth BRUNNER Jürgen HEINZE Biologie I University of RegensburgRegensburgGermany Department of Entomology Ain Shams UniversityCairoEgypt

Discrimination between nestmates and non-nestmates in social insects is thought to rely on the pattern of cuticular *** investigated the cuticular hydrocarbon profiles of 2 parapatric sibling ant species,Temnothorax nylanderi(Förster,1850)and Temnothorax crassispinus(Karavaiev,1926),and their *** found that although the profiles show considerable similarities,a discriminant analysis based on the relative peak areas of cuticular hydrocarbons separates the 3 *** profiles of hybrids were not consistently intermediate between those of the paternal species,suggesting either non-additive interactions among the parental biosynthetic pathways or systematic differ-ences in environment-derived odor cues.

关键词： colony odor cuticular hydrocarbons hybridization Temnothorax

Strength and Wear Behavior of Mg Alloy AE42 Reinforced with Carbon Short Fibers

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 31-40页

作者： Sabbah Ataya Naser A.Alsaleh mohamed M.el-sayed Seleman Metallurgical and Materials Engineering Department Faculty of Petroleum and Mining Engineering Suez University Department of Mechanical Engineering College of Engineering Al Imam Mohammad Ibn Saud University

In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it necessary to assess their wear performance. Little research data have been discussed on wear behavior of Mg alloy AE42 matrix and its composites. Thus, this paper reports wear behavior of magnesium alloy AE42(Mg–Al–Mn—RE; rare earth) and its composite AE42-C, which contains 23 vol% of randomly oriented carbon short fibers. Materials characterization, including density measurements, hardness testing, microstructures investigation, and compression testing at temperatures of 25, 150,and 300 °C, were conducted. Wear tests were performed under various loads and sliding distances. Wear mechanisms were also proposed based on the examination of worn surfaces using optical microscopy and scanning electron microscopy equipped with EDX(energy-dispersive X-ray spectrometry) analysis system. The hardness of AE42-23 vol% C composite is twice the hardness of the Mg matrix alloy AE42. Significant improvements to yield stress and compressive strength at temperatures of 25, 150, and 300 °C of the composite versus the AE42 alloy are achieved. Wear resistance of the composite is improved considerably versus that of the Mg alloy AE42 at the various sliding distances. Smearing of graphite on the worn surface produces a lubricating film that delays change from mild to severe wear of the composite, especially at high loads. EDX analysis of the worn surface shows oxidation of the matrix alloy at higher wear loads, and this mechanism decreases in the presence of carbon fibers under the same loads. Abrasive wear, oxidation, and plastic deformation are the dominant wear mechanisms for the alloy matrix AE42, whereas mainly abrasive wear is the wear mechanism of AE42-23 vol% C composite under the proposed testing conditions.

关键词： Magnesium composites Carbon short fibers Compressive strength Wear resistance Wear mechanisms

Micro-fabrication of ceramics:Additive manufacturing and conventional technologies

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Journal of Advanced Ceramics 2021年第1期10卷 1-27页

作者： Hany HASSANIN Khamis ESSA Amr elSHAER mohamed IMBABY Heba H.el-MONGY Tamer A.el-sayed School of Engineering Canterbury Christ Church UniversityCanterburyCT11QUUK University of Birmingham EdgbastonB152TTUK Kingston University London Penrhyn RoadKingston Upon ThamesSurreyKT12EEUK Department of Mechanical Design Faculty of EngineeringMatariaHelwan UniversityP.O.Box.11718CairoEgypt Jubail University College Mechanical EngineeringKingdom of Saudi Arabia Center for Applied Dynamics Research(CADR) School of EngineeringUniversity of AberdeenAberdeenAB243UEUK

Ceramic materials are increasingly used in micro-electro-mechanical systems(MEMS)as they offer many advantages such as high-temperature resistance,high wear resistance,low density,and favourable mechanical and chemical properties at elevated ***,with the emerging of additive manufacturing,the use of ceramics for functional and structural MEMS raises new opportunities and *** paper provides an extensive review of the manufacturing processes used for ceramic-based MEMS,including additive and conventional manufacturing *** review covers the micro-fabrication techniques of ceramics with the focus on their operating principles,main features,and processed *** that need to be addressed in applying additive technologies in MEMS include ceramic printing on wafers,post-processing at the micro-level,resolution,and quality *** paper also sheds light on the new possibilities of ceramic additive micro-fabrication and their potential applications,which indicates a promising future.

关键词： micro-electro-mechanical system(MEMS) micro-fabrication ceramics micro parts additive manufacturing

Gastrointestinal and hepatic diseases during the COVID-19 pandemic:Manifestations,mechanism and management

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World Journal of Gastroenterology 2021年第28期27卷 4504-4535页

作者： Dina Zakaria mohamed Mai el-sayed Ghoneim Sally el-sayed Abu-Risha Ramy Ahmed Abdelsalam mohamed Abdelhalem Farag Department of Pharmacology and Toxicology Faculty of PharmacyTanta UniversityTanta 31511Egypt Department of Pharmacology and Toxicology Faculty of PharmacyUniversity of Sadat CityMenoufia 32632Egypt Department of Pathology Faculty of MedicineMansoura UniversityMansoura 35511Egypt Department of Pediatrics Nebru General HospitalNebru 35511Egypt

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is considered the causative pathogen of coronavirus disease 2019(COVID-19)and has become an international danger to human *** respiratory transmission and symptoms are still the essential manifestations of COVID-19,the digestive system could be an unconventional or supplementary route for COVID-19 to be transmitted and manifested,most likely due to the presence of angiotensin-converting enzyme 2(ACE2)in the gastrointestinal *** addition,SARS-CoV-2 can trigger hepatic injury via direct binding to the ACE2 receptor in cholangiocytes,antibodydependent enhancement of infection,systemic inflammatory response syndrome,inflammatory cytokine storms,ischemia/reperfusion injury,and adverse events of treatment *** symptoms,including anorexia,nausea,vomiting,and diarrhea,which are unusual in patients with COVID-19,and some digestive signs may occur without other respiratory ***,SARS-CoV-2 can be found in infected patients’stool,demonstrating the likelihood of transmission through the fecal-oral *** addition,liver function should be monitored during COVID-19,particularly in more severe *** review summarizes the evidence for extra-pulmonary manifestations,mechanisms,and management of COVID-19,particularly those related to the gastrointestinal tract and liver.

关键词： COVID-19 Angiotensin-converting enzyme 2 Gastrointestinal Inflammatory bowel disease Liver Management