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Ahmed, T. S., O. Y. Abdelaziz, and G. W. Roberts, "Hydrogenolysis of Glycerol over γ-Al2O3-Supported Iridium Catalyst", Periodica Polytechnica Chemical Engineering, vol. 61, issue 4, pp. 295-300, 2017.
Alaasar, M., M. Prehm, and C. Tschierske, "Hydrogen-​bonded supramolecular complexes formed between isophthalic acid and pyridine-​based derivatives", Liquid Crystals, vol. 38, issue 7, pp. 925, 2011.
Alaasara, M., C. Tschierskeb, and M. Prehmb, "Hydrogen-bonded Supramolecular Complexes Formed Between Isophthalic Acid and Pyridine-Based Derivatives", Liquid Crystals, 2011. Abstract

Two types of supramolecular liquid crystals were prepared through the formation of double hydrogen-bonded complexes between isophthalic acid (A) and two different groups of pyridine-based derivatives ( In and Ia-e). The first group of the base, In (molecular formula 4-CnH2n+1OC6H4COOC6H4-N=N-C5H4N) homologues differ from each other by the number of carbon atoms (n) in the alkoxy chain, which varies between 8, 10, 12 and 14 carbons. The second group of the pyridine-based derivatives, Ia-e (molecular formula 4-X-C6H4COOC6H4-N=N-C5H4N) analogues differ from each other by the terminal polar substituent, X, that changes between OCH3, CH3, H, NO2 and Br groups. In this manner two different groups of complexes are formed, one of them is A : 2In, (Group A), and the other is A : 2Ia-e, (Group B). All complexes were investigated for their mesophase behaviour by differential scanning calorimetry and polarised light microscopy. The formation of 1:2 hydrogen-bonded complexes was confirmed by FTIR spectroscopy and binary phase diagrams. Most complexes A and B show nematic and/or SmA phases. X-ray diffraction of the SmA phase of a representative complex of type A indicates a layer distance corresponding to only half of the length of the H-bonded complexes which is interpreted by a phase structure where these complexes adopt a U-shape which intercalate and form non-polar SmA phases.

Abdelkader, M. M., and Mohamed Abdelmohsen, "Hydrogen-bonded and supramolecular ferroelectricity in a new hybrid (C 12 H 25 NH 3 ) 2 CoCl 4", Materials Research Express, vol. 6, issue 2, pp. 025608, 2019.
Mansour, A. M., and N. T. Abdel-Ghani, "Hydrogen-bond effect, spectroscopic and molecular structure investigation of sulfamethazine Schiff-base: Experimental and quantum chemical calculations", Journal of Molecular Structure, vol. 1040, pp. 226-237, 2013.
Ahmed, H. H., F. M. Taha, H. S. Omar, H. M. Elwi, and M. Abdelnasser, "Hydrogen sulfide modulates SIRT1 and suppresses oxidative stress in diabetic nephropathy.", Molecular and cellular biochemistry, vol. 457, issue 1-2, pp. 1-9, 2019. Abstract

DN is recognized as not only a leading cause of end stage renal disease (ESRD) but also an independent risk factor for cardiovascular disease (CVD). Novel therapeutic approaches to diabetic nephropathy (DN) are needed, or else, healthcare resources will be overwhelmed by the expected worldwide increase in associated cases of ESRD and CVD. Reactive oxygen species (ROS) and advanced glycation end product (AGE) are implicated in the development of DN. Hydrogen sulfide (HS) is known for its antioxidant and antiapoptotic characteristics. Simultaneously diabetics have lower HS levels. Thus, it is worth investigating the use of HS in treatment of DN. To investigate the potential therapeutic role of HS in DN. Sixty male rats were divided into four groups: control, DN, DN+NaHS30 µmol/kg/day and DN+NaHS100 µmol/kg/day. Fasting blood sugar (FBS), kidney function tests, SIRT1 activity, superoxide dismutase activity (SOD), malondialdehyde (MDA) and expression of caspase3 and p53 in renal tissues were assessed. Kidney was examined histopathologically. DN rats had higher FBS, renal dysfunction, decreased SIRT1 and SOD activity levels, increased caspase3 and p53 relative expression and increased MDA in renal tissues. NaHS increased SIRT1 and reversed biochemical, apoptotic, oxidant and pathologic parameters characteristic of DN, with better results using a dose of 100 µmol/kg/day. HS has a protective role against DN through decreasing FBS, ROS, apoptosis and upregulating SIRT1, thus preserving renal cells from further damage caused by DM.

Abdelmonema, M., N. N. Shahina, L. A. Rashed, H. A. A. Aminc, A. A. Shamaa, and A. A. Shaheena, "Hydrogen sulfide enhances the effectiveness of mesenchymal stem cell. therapy in rats with heart failure: In vitro preconditioning versus in vivo codelivery. ", Biomedicine & Pharmacotherapy , vol. 112, 2019.
Abdelmonem, M., N. N. Shahin, L. A. Rashed, H. A. A. Amin, A. A. Shamaa, and A. A. Shaheen, "Hydrogen sulfide enhances the effectiveness of mesenchymal stem cell therapy in rats with heart failure: In vitro preconditioning versus in vivo co-delivery.", Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie, vol. 112, pp. 108584, 2019 Feb 18. Abstract

Stem cell therapy represents a promising therapeutic avenue for cardiac disorders, including heart failure. Although stem cell transplantation showed encouraging preliminary results, the outcomes of clinical studies are still unsatisfactory. This study aimed to compare the outcomes of two therapeutic approaches, in vivo co-delivery of sodium hydrogen sulfide (NaHS) concomitant with bone marrow-derived mesenchymal stem cell (BMSC) transplantation and in vitro preconditioning of BMSCs with NaHS, both of which are intended to promote the success of stem cell therapy in rats with isoprenaline-induced heart failure. Heart failure developed 4 weeks after the subcutaneous injection of isoprenaline (170 mg/kg) for 4 consecutive days. The in vivo approach involved the co-delivery of intraperitoneally administered NaHS concomitant with BMSC transplantation for a period of 14 days. The in vitro approach involved preconditioning BMSCs with NaHS for 30 min before transplantation. Compared to treatment with BMSCs alone, in vitro preconditioning of BMSCs with NaHS improved left ventricular function as measured by echocardiography and electrocardiography and enhanced stem cell homing, proliferation and differentiation as manifested by higher cardiac expression of GATA-4 and myocyte enhancer factor 2. Moreover, the measurement of cardiac transforming growth factor beta 1 levels and histopathological investigation revealed mitigated fibrosis and myocardial injury scores. Compared with BMSC therapy alone, the in vivo approach enhanced stem cell homing and differentiation, alleviated fibrosis and augmented vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) expression. In conclusion, NaHS can potentiate the efficiency of BMSC therapy for heart failure by in vitro preconditioning or in vivo co-delivery. The in vitro approach is superior with regard to improving cardiac function in addition to enhancing stem cell proliferation, while the in vivo approach is superior with regard to increasing cardiac VEGF and eNOS expression.

Abdelmonem, M., N. N. Shahin, L. A. Rashed, H. A. A. Amin, A. A. Shamaa, and A. A. Shaheen, "Hydrogen sulfide enhances the effectiveness of mesenchymal stem cell therapy in rats with heart failure: In vitro preconditioning versus in vivo co-delivery.", Biomedicine & Pharmacotherapy, vol. 112, pp. 108584, 2019.
Aboulhoda, B. E., L. A. Rashed, H. A. Ahmed, Eman MM Obaya, W. Ibrahim, Marwa AL Alkafass, Sarah A Abd El‐Aal, and A. M. Shams Eldeen, "Hydrogen sulfide and mesenchymal stem cells‐extracted microvesicles attenuate LPS‐induced Alzheimer's disease", Journal of Cellular Physiology, vol. 236, issue 8, pp. 5994-6010, 2021.
Sata, S., M. I. Awad, M. S. El-Deab, T. Okajima, and T. Ohsaka, "Hydrogen spillover phenomenon: Enhanced reversible hydrogen adsorption/desorption at Ta2O5-coated Pt electrode in acidic media", Electrochimica Acta, vol. 55, pp. 3528-3536, 2010.
W.A.Badawy, H. E. El-Feky, N. H. Helal, and H. H. Mahmmed, "Hydrogen Production on Molybdenum in H2SO4 Solutions", J. Power Sources, vol. 271 , pp. 480-488, 2014.
de Lux, C. G., S. Joshi-Barr, E. a Mahmoud, and A. Almutairi, "Hydrogen peroxide-responsive polymeric nanoparticles for diagnostics and drug delivery in inflammatory disease", ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, vol. 245: AMER CHEMICAL SOC 1155 16TH ST, NW, WASHINGTON, DC 20036 USA, 2013. Abstract
Khalil, M. W., and A. M. A. Rahim, "Hydrogen Evolution Reaction on Titanium and Oxide-Covered Titanium Electrodes", Mat.-wiss. u. Werkstofftech. , vol. 22, pp. 390-395, 1991.
El-Deab, M. S., M. E. El-Shakre, B. E. El-Anadouli, and B. G. Ateya, "Hydrogen Evolution on Stacked Copper Screen Electrodes from Flowing Alkaline Solutions", International Journal of Hydrogen Energy, vol. 21, pp. 273-280, 1996.
Azza A. Ghoneim, Renad S. El-Kamel, and A. M. Fekry, "Hydrogen evolution and quantum calculations for potassium sorbate as an efficient green inhibitor for biodegradable magnesium alloy staples used for sleeve gastrectomy surgery", i n t e rna t i onal journal o f hydrogen energy , vol. 45, pp. 2 4 3 7 0-2 4 3 8 2, 2020.
El-Karim, R. A., S. El-Raghy, M. Megahed, and H. Ghazal, "Hydrogen embrittlement of AISI 4140 stud bolts", Materials performance, vol. 44, no. 9: National Association of Corrosion Engineers, pp. 50–54, 2005. Abstract
Buchet, R., L. Beauvais, and C. Sandorfy, "Hydrogen bond equilibrium constants of some unusual nucleotide base pairs.", Journal of biomolecular structure & dynamics, vol. 2, issue 1, pp. 221-32, 1984 Aug. Abstract

Approximate hydrogen bond association constants were determined for base pairs formed by an adenine derivative and a number of unusual pyrimidine bases. A series is found in which the H-bond strength in the base-pairs varies. In certain cases the H-bond equilibrium constant is larger than in the adenine-thymine pair. Inosine derivatives seem to have a non-negligible chance of replacing guanosine in the guanosine-cytosine pair. Infrared, near-infrared (overtone) and NMR spectra were used to determine the equilibrium constants.

AHMED, A. A., R. H. Hilal, and M. F. Shibl, "Hydrogen bond coupling in Sodium Dihydrogen Triacetate. Journal of Molecular Modeling", Journal of Molecular Modeling, 2014.
Ahmed, A. A., R. H. Hilal, and M. F. Shibl, "Hydrogen bond coupling in sodium dihydrogen triacetate", Journal of molecular modeling, vol. 20, issue 8: Springer Berlin Heidelberg, pp. 2363, 2014. Abstract
Ahmed, A. A., R. H. Hilal, and M. F. Shibl, "Hydrogen bond coupling in sodium dihydrogen triacetate", Journal of molecular modeling, vol. 20, issue 8: Springer Berlin Heidelberg, pp. 1-10, 2014. Abstract
Abbass, M., A. A. El-Rashidy, K. M. Sadek, S. El Moshy, I. A. Radwan, D. Rady, C. E. Dörfer, and K. M Fawzy El-Sayed, "Hydrogels and Dentin–Pulp Complex Regeneration: From the Benchtop to Clinical Translation", Polymers, vol. 12, issue 12: Multidisciplinary Digital Publishing Institute, pp. 2935, 2020. Abstract
Abbass, M. M. S., A. A. El-Rashidy, K. M. Sadek, S. El Moshy, I. A. Radwan, D. Rady, C. E. Dörfer, and K. M Fawzy El-Sayed, "Hydrogels and Dentin-Pulp Complex Regeneration: From the Benchtop to Clinical Translation.", Polymers, vol. 12, issue 12, 2020. Abstracthydrogels_and_dentin-pulp_complex_regeneration_from_the_benchtop_to_clinical_translation.pdf

Dentin-pulp complex is a term which refers to the dental pulp (DP) surrounded by dentin along its peripheries. Dentin and dental pulp are highly specialized tissues, which can be affected by various insults, primarily by dental caries. Regeneration of the dentin-pulp complex is of paramount importance to regain tooth vitality. The regenerative endodontic procedure (REP) is a relatively current approach, which aims to regenerate the dentin-pulp complex through stimulating the differentiation of resident or transplanted stem/progenitor cells. Hydrogel-based scaffolds are a unique category of three dimensional polymeric networks with high water content. They are hydrophilic, biocompatible, with tunable degradation patterns and mechanical properties, in addition to the ability to be loaded with various bioactive molecules. Furthermore, hydrogels have a considerable degree of flexibility and elasticity, mimicking the cell extracellular matrix (ECM), particularly that of the DP. The current review presents how for dentin-pulp complex regeneration, the application of injectable hydrogels combined with stem/progenitor cells could represent a promising approach. According to the source of the polymeric chain forming the hydrogel, they can be classified into natural, synthetic or hybrid hydrogels, combining natural and synthetic ones. Natural polymers are bioactive, highly biocompatible, and biodegradable by naturally occurring enzymes or via hydrolysis. On the other hand, synthetic polymers offer tunable mechanical properties, thermostability and durability as compared to natural hydrogels. Hybrid hydrogels combine the benefits of synthetic and natural polymers. Hydrogels can be biofunctionalized with cell-binding sequences as arginine-glycine-aspartic acid (RGD), can be used for local delivery of bioactive molecules and cellularized with stem cells for dentin-pulp regeneration. Formulating a hydrogel scaffold material fulfilling the required criteria in regenerative endodontics is still an area of active research, which shows promising potential for replacing conventional endodontic treatments in the near future.