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S A Ismail

Publications and source records attributed to S A Ismail.

15 recordsLinked to original sources
PubMed2005

Structural analysis of human liver glyceraldehyde-3-phosphate dehydrogenase.

The crystal structure of human liver glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has been determined. This structure represents the first moderate-resolution (2.5 A) and crystallographically refined (Rfree = 22.9%) human GAPDH structure. The liver GAPDH structure consists of a homotetramer, each subunit of which is bound to a nicotinamide adenine dinucleotide (NAD+) molecule. The GAPDH enzyme has glycolytic and non-glycolytic functions, both of which are of chemotherapeutic interest. The availability of a high-quality human GAPDH structure is a necessity for structure-based drug design. In this study, structural differences between human liver and skeletal muscle GAPDHs are reported in order to understand how these two enzymes might respond to anti-trypanosomatid GAPDH inhibitors.

Animals↗
PubMed2001

Effectiveness of immersion treatments with acids, trisodium phosphate, and herb decoctions in reducing populations of Yarrowia lipolytica and naturally occurring aerobic microorganisms on raw chicken.

Yarrowia lipolytica, one of the predominant yeasts in raw poultry, is believed to play a role in spoilage. This study was undertaken to investigate treatments to control the growth of Y. lipolytica on raw chicken stored at refrigeration temperature. Raw chicken wings inoculated with a mixture of five strains of Y. lipolytica isolated from raw poultry were dipped in solutions containing 2, 5, or 8% lactic acid, 2% lactic acid containing 0.2, 0.4, or 0.8% potassium sorbate or sodium benzoate, and 4, 8, or 12% trisodium phosphate solution. Populations of the yeast and total aerobic microorganisms were determined before and after treatment. Immersion of wings in 2% lactic acid (with or without 0.2% potassium sorbate or sodium benzoate) or 4% trisodium phosphate caused a significant (alpha = 0.05) reduction in numbers of Y. lipolytica and aerobic microorganisms. Treatment with 2% lactic acid containing 0.4 or 0.8% preservative did not result in additional significant reductions. Treatment of chicken wings with 2% lactic acid or 8% trisodium phosphate significantly reduced numbers of Y. lipolytica by 1.47 and 0.65 log10 cfu/g, respectively, and aerobic microorganisms by 2.60 and 1.21 log10 cfu/g, respectively, compared to controls. Growth of Y. lipolytica on wings stored at 5 degrees C for up to 9 days, however, was not affected by these treatments. Significant reductions in the population of Y. lipolytica occurred when the yeast was inoculated into 100% basil, marjoram, sage, and thyme decoctions, but not in 100% oregano or rosemary decoctions, held at 5 degrees C for 24 h. Treatment of chicken wings with 100% sage or thyme decoctions significantly reduced populations of Y. lipolytica but did not control its growth during storage at 5 degrees C for up to 9 days. The small, temporary decreases in numbers of Y. lipolytica and aerobic microorganisms resulting from immersion treatment of chicken wings with sage and thyme decoctions render these treatments of questionable value as preservation interventions.

Animals↗
PubMed2000

Presence and changes in populations of yeasts on raw and processed poultry products stored at refrigeration temperature.

A study was undertaken to determine populations and profiles of yeast species on fresh and processed poultry products upon purchase from retail supermarkets and after storage at 5 degrees C until shelf life expiration, and to assess the potential role of these yeasts in product spoilage. Fifty samples representing 15 commercial raw, marinated, smoked, or roasted chicken and turkey products were analyzed. Yeast populations were determined by plating on dichloran rose bengal chloramphenicol (DRBC) agar and tryptone glucose yeast extract (TGY) agar. Proteolytic activity was determined using caseinate and gelatin agars and lipolytic activity was determined on plate count agar supplemented with tributyrin. Populations of aerobic microorganisms were also determined. Initial populations of yeasts (log10 cfu/g) ranged from less than 1 (detection limit) to 2.89, and increased by the expiration date to 0.37-5.06, indicating the presence of psychrotrophic species. Highest initial populations were detected in raw chicken breast, wings, and ground chicken, as well as in turkey necks and legs, whereas roasted chicken and turkey products contained less than 1 log10 cfu/g. During storage, yeast populations increased significantly (P < or = 0.05) in whole chicken, ground chicken, liver, heart and gizzard, and in ground turkey and turkey sausage. Isolates (152 strains) of yeasts from poultry products consisted of 12 species. Yarrowia lipolytica and Candida zeylanoides were predominant, making up 39 and 26% of the isolates, respectively. Six different species of basidiomycetous yeasts representing 24% of the isolates were identified. Most Y. lipolytica strains showed strong proteolytic and lipolytic activities, whereas C. zeylanoides was weakly lipolytic. Results suggest that yeasts, particularly Y. lipolytica, may play a more prominent role than previously recognized in the spoilage of fresh and processed poultry stored at 5 degrees C.

Animals↗
PubMed1987

A randomized trial of 13-cis retinoic acid with or without cytosine arabinoside in patients with the myelodysplastic syndrome.

Ninety-eight consecutive patients with myelodysplastic syndrome were randomized to a treated or a control group, both receiving conventional supportive therapy. The treated group were given 13-cis-retinoic acid 20 mg/d if marrow blasts were less than or equal to 5% or cytosine arabinoside 10 mg/d subcutaneously on 6 d/week if marrow blasts were 6-30%, to which retinoic acid was added after 12 weeks. Serum levels of the drugs in the treated group were similar to those that would produce inhibition of CFU-GM growth in vitro. In patients in the low blast group receiving retinoic acid, myeloid surface antigens reverted from an abnormal to a normal pattern. Log rank analysis carried out after 25 months showed no significant difference in survival between the treated and control group, either in the total patient population or in the high and low blast groups considered separately. However, analysis of 39 non-sideroblastic patients with less than or equal to 5% blasts showed an increase in survival in the treated group.

Adult↗
PubMed1986

Antibacterial effect and toxicity of synthesized salicylanilide derivatives.

5 nitro- and chloro-salicylanilide derivatives were synthesized by a simple condensation reaction between phenylsalicylate and the required nitroaniline derivative. The compounds were subjected to direct chlorination in CCl4 without any catalyst and were identified by microanalysis, m. p. and spectral studies. The antibacterial activity was investigated against Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus. The prepared derivatives were evaluated for their acute toxicity on Swiss albino mice. The compounds 5,2'-dichloro-4'-nitrosalicylanilide and salicyl-3'-nitroanilide were the most active against the test organisms, but they showed fluctuating toxicity effect at the dose of 500 mg/kg. The structure-activity relationship and the toxicity tests verified the compound salicyl-4'-nitroanilide as a reasonable antibacterial agent against the four test organisms without any sign of toxicity symptoms up to the dose of 1000 mg/kg.

Animals↗
PubMed1976

Hereditary prolongation of the Q-T interval. Genetic observations and management in three families with twelve affected members.

Three families with the prolongation Q-T interval are described. Two demonstrated the nonsex-linked dominant mode of inheritance of the condition without neural deafness (the Romano-Ward syndrome). Family A had four affected members in three generations. Family B had three affected members in two generations, but the parents of the affected children were distant relatives. Family C had five affected members in three generations. Of the nine living affected members, seven were asymptomatic and never experienced syncope. The remaining two, aged 7 and 9 years, respectively, had multiple syncopal attacks. Of three affected members who died, two had electrocardiograms before death. The thirds, an apparently healthy boy of 14 years, had a single syncopal attack 13 months before he died in his sleep. The nature of the dysrhythmia causing syncope was documented in two cases. One of the affected children was treated successfully with a permanent demand pacemaker and propranolol, the other with propranolol alone. The electrophysiologic findings and the management of both symptomatic and asymptomatic patients are discussed.

Adolescent↗
PubMedDate not supplied

Use of co-immobilized beta-amylase and pullulanase in reduction of saccharification time of starch and increase in maltose yield.

Beta-amylase and pullulanase were co-immobilized to poly(acrylamide-acrylic acid) resin [P(AAm-AAc)] using 1-ethyl-3-(3-dimethylaminopropyl) carbodimide hydrochloride (EDC). The combined beta-amylase and pullulanase activity was 32% relative to the nonimmobilized beta-amylase. Co-immobilization of beta-amylase and pullulanase increased the maltose yield compared to thart of the immobilized beta-amylase alone and reduced the saccharification time to about 50 h. The results showed that there is a significant increase in the thermal stability, pH stability, and stability toward gamma irradiation. The results also suggest that the co-immobilization of beta-amylase and pullulanase is a potentially useful approach for commercial starch hydrolysis.

Acrylic Resins↗