Publications by authors named "Mohammed A Sallam"

Dehydrative cyclization of 4-(D-altro-pentitol-1-yl)2-phenyl-2H-1,2,3-triazole in basic medium with one moler equivalent of p-toluene sulfonyl chloride in pyridine solution gave the homo-C-nucleoside 4-(2,5-anhydro-D-altro-1-yl)-2-phenyl-2H-1,2,3-triazole. The structure and anomeric configuration was determined by acylation, nuclear magnetic resonance (NMR), and mass spectroscopy. The stereochemistry at the carbon bridge of homo-C-nucleoside 2-phenyl-2H-1,2,3-triazoles was determined by circular dichroism (CD) spectroscopy.

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Macrophages play an important role in attempt to eliminate mycobacteria, via production of cytokines, including interleukin-1, and interleukin-12. Bacillus Calmitte Guerin (BCG) vaccination, known to induce interleukin-1β in tuberculosis, was originally aimed at tuberculosis control, but it showed efficacy against leprosy. Our aim was to estimate serum levels of interleukin-1β and interleukin-12, in leprosy, and to assess the impact of previous BCG vaccination on their levels.

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The circular dichroism of a series of acyclic polyhydroxyalkyl benzimidazole C-nucleoside analogs was correlated with the stereochemistry of the chiral carbon atom α to the benzimidazole base moiety. This correlation was used for the assignment of the anomeric configuration of 2-(β-L-erythrofuranosyl) benzimidazole C-nucleoside analogs without a need to have the other anomer on hand, in a similar manner to the correlation obtained for assignment of the anomeric configuration of triazole C-nucleoside analogs.

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Background: Information on patterns of skin diseases in Egypt is scanty.

Methods: The medical records of patients attending dermatology outpatient clinics at Ain Shams University Hospitals from January 2001 to December 2001 were retrieved. Valid data of 7528 patients were included in the study.

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Treatment of 4-(d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole with one molar equivalent of 2,4,6-triisopropylbenzenesulfonyl chloride (TIBSCl) in pyridine solution afforded the homo-C-nucleoside analog; 4-(2,5-anhydro-d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole in 54% yield and 4-(α-d-arabinopyranosyl)-2-phenyl-2H1,2,3-triazole analog in 3% yield. The 4-(5-O-triisopropylbenzenesulfonyl)-d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole analog was isolated as an intermediate and identified as its tetra-O-acetyl derivative. The 4-(5-chloro-5-deoxy-d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole analog was isolated as a byproduct.

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Acid-catalyzed dehydrative cyclization of 5-deoxy-L-manno-pentitol-1-yl)-2-heptulose bisphenylhydrazone and subsequent reflux with copper sulfate gave an anomeric mixture of 4-(5-deoxy-alpha,beta-L-arabinofuranosyl)-2-phenyl-2H-1,2,3-triazole C-nucleoside analogs. The mixture was separated by chromatography, and the anomeric compositions configurations of the components were determined by CD, NMR, mass spectroscopy, and acylation.

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Treatment of D-arabino-tetritol-1-yl-benzimidazole with P-toluenesulfonyl chloride (1molequiv) in pyridine, afforded the N-bridgehead heterocycles, 2R,3R,4S-trihydroxy-1:2:3:4-tetrahydropyridino[1,2-a]benzimidazole. The structure of the latter compound was determined by acylation, (1)H, and (13)C NMR spectroscopy and mass spectrometry.

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The circular dichroism (CD) of a series of acyclic C-nucleoside analogs; 4-(pentahydroxypentyl-1-yl)-2-phenyl-2H-1,2,3-triazoles [1-5] and 4-(D-glycero-D-gulo)-2-phenyl-2H-1,2,3-triazole 6, are reported. A correlation between the sign of the Cotton effect at the maximal UV absorption and the absolute configuration of the carbon atom alpha- to the triazole base moiety is reported. The CD of anomeric 4-(alpha,beta-D-arabinofuranosyl)- and 4-(alpha,beta-D-arabinopyranosyl)-2-phenyl-2H-1,2,3-triazole C-nucleosides are reported.

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In summary, a coronary artery bypass graft was carried out on an awake patient with the aid of lumbar and thoracic epidural anesthesia, due to dissection of the saphenous graft from the lower limb. The procedure was done using an off pump technique and the patient required no extra sedation of analgesia. In conclusion, we think that many high risk patients could be treated using this technique and that awake CABG seems to be a promising adjunct to current minimally invasive CABG techniques.

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Dehydrative cyclization of epimeric 4-(L-xylo- and L-lyxo-tetritol-1-yl)-2-phenyl-2H-1,2,3-triazoles afforded the anomeric alpha and beta-L-threofuranosyl analogs. The anomeric configuration of the formed anomeric C-nucleoside analogs was determined by circular dichroism and NMR spectroscopy.

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The alginates from five species of brown algae from the Egyptian Red Sea coast, namely: Cystoseira trinode, Cystoseira myrica, Sargassum dentifolium, Sargassum asperifolium, and Sargassum latifolium, were isolated and their compositions and structures studied by 1H NMR spectroscopy. All the alginates studied contain more guluronic acid (G) than mannuronic acid (M) and have a homopolymeric block-type structure (eta<1). The intrinsic viscosity of the alginate samples range from 8.

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Circular dichroism spectra of a series of 4-(tetra-hydroxy-tetryl-1-yl)2-phenyl-2H-1,2,3-triazoles were measured and the sign of their Cotton effects was correlated to the absolute configuration of the hydroxyl group alpha to the triazole base moiety. Those having the D-glycero-configuration in their Fischer projection formula show positive Cotton effect and those with the L-glycero-configuration show negative Cotton effect. This correlation was extended for the assignment of the anomeric configuration of the corresponding glycofuranosyl-C-nucleosides.

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