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A A Aly

Publications and source records attributed to A A Aly.

14 recordsLinked to original sources

Simple synthesis of novel diphenylsulfapyrimidine acetates from chalcones and their antimicrobial activity.

Given the significant low yield (19-43%) in reported results on the cyclocondensation of sulfaguanidine acetate with chalcones, a careful reinvestigation was carried out. A new series of chalcones, bearing electron-attracting groups in the aromatic moiety, have been used as precursors in the synthesis of diphenylsulfapyrimidine acetates with good yield. All synthesized compounds were active against G(+)- and G(-)-bacteria, and fungi. Combination of substituents (Cl, OMe, NO2, etc.) enhanced antimicrobial activity. Derivative with two NO2 groups exhibits an activity comparable with sulfadiazine.

Acetates↗

Alpha,beta-unsaturated 4-oxo acids in heterocylic synthesis. II. Behavior of 3-(1,1-dioxadibenzothein-4-oyl)acrylic acid towards carbon nucleophiles under Michael reaction condition.

3-(1,1-Dioxadibenzothien-4-oyl)acrylic acid (1) was condensed with compounds containing active methylene groups under Michael reaction conditions to furnish the Michael adducts (lactones 2a-c, lactams 3a-c, ketones 4a,b). The behavior of these adducts toward the action of hydrazine hydrate were investigated. The compounds were tested for their biological properties.

Acrylates↗

Phylogenetic classification of serotype III group B streptococci on the basis of hylB gene analysis and DNA sequences specific to restriction digest pattern type III-3.

Previous work divided serotype III group B streptococci (GBS) into 3 major phylogenetic lineages (III-1, III-2, and III-3) on the basis of bacterial DNA restriction digest patterns (RDPs). Most neonatal invasive disease was caused by III-3 strains, which implies that III-3 strains are more virulent than III-2 or III-1 strains. In the current studies, all RDP III-3 and III-1 strains expressed hyaluronate lysase activity; however, all III-2 strains lack hyaluronate lysase activity, because the gene that encodes hyaluronate lysase, hylB, is inactivated by IS1548. Subtractive hybridization was used to identify 9 short DNA sequences that are present in all the III-3 strains but not in any of the III-2 or III-1 strains. With 1 exception, these III-3-specific sequences were not detected in nonserotype III GBS. These data further validate the RDP-based subclassification of GBS and suggest that lineage-specific genes will be identified, which account for the differences in virulence among the lineages.

Blotting, Southern↗

Genetic polymorphisms of group B streptococcus scpB alter functional activity of a cell-associated peptidase that inactivates C5a.

Many group B Streptococcus agalactiae strains and other pathogenic streptococci express a cell-associated peptidase that inactivates C5a (C5a-ase), the major neutrophil chemoattractant produced by activation of the complement cascade. Type III group B streptococci (GBS) can be classified genotypically into three restriction digest pattern types. Functional C5a-ase activity of GBS correlates with this genetic typing; therefore, we sought to identify a genetic basis for this phenomenon. Southern hybridization confirms that all type III GBS contain scpB, the gene encoding GBS C5a-ase. GBS strains with high C5a-ase functional activity and those with no or very low activity both express immunoreactive C5a-ase. The scpB sequence of strain I30, which has high C5a-ase activity, is 98.2% homologous to the previously reported serotype II GBS scpB sequence. The scpB sequences of strains I25 and GW, which have low or no C5a-ase activity, are identical. The predicted I25 and GW C5a-ase proteins share a four-amino-acid deletion affecting the protease histidine active-site consensus motif. Recombinant I30 C5a-ase has good functional activity, whereas recombinant I25 C5a-ase has low activity. These data demonstrate that functional C5a-ase differences between type III GBS strains are attributable to a genetic polymorphism of scpB. The ubiquitous expression of C5a-ase, irrespective of functional activity, suggests that C5a-ase may have a second, as yet unidentified, function.

Adhesins, Bacterial↗

Case survey of management of cellulitis in a tertiary teaching hospital.

OBJECTIVE: To examine management of cellulitis in a tertiary teaching hospital, identify inefficiencies and suggest revised management guidelines. DESIGN: Retrospective case survey, based on patient hospital records. SETTING: Heidelberg Repatriation Hospital, Melbourne, Victoria (a tertiary teaching hospital), in 1991 and 1992. SUBJECTS: All patients admitted with lower-limb cellulitis as the primary diagnosis. RESULTS: 118 patients were included. Underlying disease predisposing to cellulitis was found in 79%, but was adequately investigated in only 20% of these. Blood cultures were performed in 55%, all with negative results. Other microbiological investigations also had poor yields. Combination therapy with intravenous (i.v.) flucloxacillin and penicillin was given to 76%, with duration varying widely (mean, six days). Where documented (73%), most patients (94%) responded to antibiotics within five days. However, in 40% of patients i.v. therapy was continued for longer and in 10% for 10 days or more, with no significant difference in outcome. Length of hospital stay averaged 13 days, with prolonged stay often associated with surgical intervention or intercurrent problems. However, 15% of patients remained in hospital longer than 10 days for no clear indication. Outpatient review was common (75%), but persistence or relapse of cellulitis was found in only four patients on review. CONCLUSIONS: Management of inpatients with cellulitis is inefficient, with excessive use of microbiological investigations, inadequate investigation and treatment of underlying disease, prolonged use of intravenous antibiotics, unnecessarily long hospital stays, questionable use of combination antibiotic therapy and excessive outpatient review (rather than review by a local medical practitioner).

Adult↗

Technetium-aspirin molecule complexes.

Technetium-aspirin and technetium-aspirin-like molecule complexes were prepared. The structure of N-acetyl-anthranilic acid (NAA) has been decided through CNDO calculations. The ionization potential and electron affinity of the NAA molecule as well as the charge densities were calculated. Comparative studies of the electronic absorption spectra of acetylthio-salicylic acid (ATS) and aspirin (Asp) reveal the structure resemblance in which the acetyl carbonyl group is perpendicular to the plane of the corresponding organic acid. The studies of the electronic absorption spectra of NAA and anthranilic acid reveal the planarity of the NAA molecule. The electronic absorption spectra of Tc(V)-Asp and Tc(V)-ATS complexes have two characteristic absorption bands at 450 and 600 nm, but the Tc(V)-NAA spectrum has one characteristic band at 450 nm. As a comparative study, Mo-ATS complex was prepared and its electronic absorption spectrum is comparable with the Tc-ATS complex spectrum.

Aspirin↗

Synthesis of biologically active [2.2]paracyclophanes.

Claisen reaction of 4-acetyl[2.2]paracyclophane (1) with ethyl acetate and diethyl oxalate affords 4-acetoacetyl[2.2]paracyclophane (2) and ethyl (4-oxaloacetyl[2.2]paracyclophane) (6), respectively. Reaction of 2 and 6 with hydrazines and CuCl2 gave the pyrazole derivatives 4 and 8 in addition to the metal complexes 5 and 9. Mannich reaction of 2 with benzylamine and paraformaldehyde yielded the piperidinone derivative 3. The biological activity of all new compounds was tested.

Animals↗

Growth characteristics of enterococci isolated from Laban Rayeb.

Eleven strains of Enterococcus (Streptococcus) faecalis isolated from Laban Rayeb, a type of fermented milk, had been studied when grew in milk. Enterococcus (Streptococcus) faecalis strains 19 and 22 were the most active strains in the production of lactic acid, acetaldehyde and diacetyl. Both strains exhibited a high proteolytic activity besides a good clean flavour. Based on the obtained results, Enterococcus (Streptococcus) faecalis 19 and 22 could be used to bring about the lactic fermentation during the manufacture of some cultured dairy products.

Acetaldehyde↗

Synthesis of some 5-azo(4'-substituted benzene-sulphamoyl)-8-hydroxyquinolines with antidotal and antibacterial activities.

5-Azo(4'-substituted benzenesulphamoyl)-8-hydroxyquinolines(III) have been prepared by coupling of the appropriate p-substituted benzenesulphamoyldiazonium acetates with 8-hydroxyquinoline. The corresponding copper chelates(IV) and iron chelates(V) were also prepared in a 1:2 metal to ligand ratio. Structures of III, IV and V were confirmed by some representative UV, IR, and NMR spectrometry in addition to microanalysis. Antidotal activity of four ligands (IIIa, IIId, IIIf, and IIIi) has been evaluated in mice against the toxicity of lead acetate and copper sulphate. Study revealed that compound IIIf elicited significant antidotal activity against lead and copper poisoning, while IIIi was potent only against lead poisoning. Antibacterial activity of compounds III, IV, and V was also determined in comparison to sulphanilamide against Staph. aureus, Bacill. cereus, and Esch. coli. The test compounds showed variable bacteriostatic activities, and some of them (IIIc, IIId, IIIf, Ve, IIIg, and Vi) are more effective than the reference drug, especially against Bacill. cereus.

Animals↗