Characterization of N-acetylneuraminic acid synthase isoenzyme 1 from Campylobacter jejuni.

Escherichia coli NeuNAc (N-acetylneuraminic acid) synthase catalyses the condensation of PEP (phosphoenolpyruvate) and ManNAc (N-acetylmannosamine) to form NeuNAc and is encoded by the neuB gene. Campylobacter jejuni has three neuB genes, one of which is very similar to the E. coli neuB gene.

Functional and biochemical characterization of a recombinant Arabidopsis thaliana 3-deoxy-D-manno-octulosonate 8-phosphate synthase.

An open reading frame, encoding for KDOPS (3-deoxy-D-manno-octulosonate 8-phosphate synthase), from Arabidopsis thaliana was cloned into a T7-driven expression vector. The protein was overexpressed in Escherichia coli and purified to homogeneity. Recombinant A.

Major histocompatibility antigens and antigen-processing molecules in retinoblastoma.

Background: Malignant transformation of cells is frequently associated with abnormalities in human leukocyte antigen (HLA) expression. These abnormalities may play a role in the clinical course of the disease, because HLAs mediate interactions of tumor cells with cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells. Retinoblastoma is the most common intraocular malignant tumor in childhood and is characterized by direct spread to the optic nerve and orbit as well as hematogeneous and lymphatic spread.

Major histocompatibility antigens and antigen-processing molecules in uveal melanoma.

Purpose: Malignant transformation of cells is frequently associated with abnormalities in the human leukocyte antigen (HLA) expression. These abnormalities may play a role in the clinical course of the disease, because HLA antigens mediate interactions of tumor cells with T cells and natural killer cells. Uveal melanoma is a highly malignant tumor of the eye and is characterized by hematogenic spread to liver.

Mechanistic insight into 3-deoxy-D-manno-octulosonate-8-phosphate synthase and 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase utilizing phosphorylated monosaccharide analogues.

Escherichia coli 3-deoxy-D-manno-octulosonate 8-phosphate (KDO8-P) synthase is able to utilize the five-carbon phosphorylated monosaccharide, 2-deoxyribose 5-phosphate (2dR5P), as an alternate substrate, but not D-ribose 5-phosphate (R5P) nor the four carbon analogue D-erythrose 4-phosphate (E4P). However, E. coli KDO8-P synthase in the presence of either R5P or E4P catalyzes the rapid consumption of approximately 1 mol of PEP per active site, after which consumption of PEP slows to a negligible but measurable rate.

Presence of a 88 kDa Eales protein in uveitis, tuberculosis, leprosy and rheumatoid arthritis.

Background: Eales disease (ED) is an idiopathic retinal vasculitis affecting young adult males. We have earlier reported the identification, purification and partial characterization of a novel 88 kDa protein found in the serum of patients with ED. The aim of the present study was to look for the 88 kDa protein in serum samples obtained from cases of retinal vasculitis mimicking ED and in other systemic inflammatory diseases.

Nutritional management of short bowel syndrome in adults.

Short bowel syndrome (SBS) comprises the sequelae of nutrient, fluid, and weight loss that occurs subsequent to greatly reduced functional surface area of the small intestine. Signs and symptoms of SBS include electrolyte disturbances; deficiencies of calcium, magnesium, zinc, iron, vitamin B12, or fat-soluble vitamin deficiency; malabsorption of carbohydrates, lactose, and protein; metabolic acidosis, gastric acid hypersecretion; formation of cholesterol biliary calculi and renal oxalate calculi; and dehydration, steatorrhea, diarrhea, and weight loss. Thorough nutritional management is the key factor in achieving an optimal outcome in SBS.

Comparative analysis of monoclonal antibody based enzyme immunoassay, modified genome electrophoresis & electron microscopy procedures for rotavirus diagnosis from faecal specimens.

Background & Objectives: Reliable and rapid diagnosis of rotavirus infection is necessary for patient management. Several newly introduced commercial enzyme immunoassays (ELISAs) have been evaluated using direct electron microscopy (DEM) with or without direct ultracentrifugation as the standard reference method, and have shown varying results.

Methods: In the present study we compared the diagnostic efficacy of the three methods viz.

Neisseria gonorrhoeae 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase does not catalyze the formation of the ribo analogue.

[figure: see text] Neisseria gonorrhoeae 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAH 7-P) synthase catalyzes an aldol-type condensation between D-erythrose 4-phosphate and phosphoenolpyruvate (PEP) to form 3-deoxy-D-arabino-heptulosonate 7-phosphate and not 3-deoxy-D-riboheptulosonate 7-phosphate. Similar to the Escherichia coli enzyme, N. gonorrhoeae DAH 7-P synthase condenses D-arabinose 5-phosphate with PEP to give 3-deoxy-D-manno-octulosonate 8-phosphate.

Probing the stereochemistry of E. coli 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (phenylalanine-sensitive)-catalyzed synthesis of KDO 8-P analogues.

The five-carbon phosphorylated monosaccharide analogues, D-arabinose 5-phosphate, D-ribose 5-phosphate, and 2-deoxy-D-ribose 5-phosphate, were separately condensed with (Z)- and (E)-[3-(2)H]-phosphoenolpyruvate (PEP) in the presence of Escherichia coli 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAH 7-P) synthase (phe) to give in the case of (Z)-[3-(2)H]-PEP (3S)-[3-(2)H]-3-deoxy-D-manno-octulosonate 8-phosphate, (3S)-[3-(2)H]-3-deoxy-D-altro-octulosonate 8-phosphate, and (3S)-[3-(2)H]-3,5-dideoxy-D-altro-octulosonate 8-phosphate, respectively, whereas incubation with (E)-[3-(2)H]-PEP gives the corresponding (3R)-monosaccharides. These results are in complete agreement with the observed facial selectivity of DAH 7-P synthase for its normal substrates D-erythrose 4-phosphate and PEP and provide direct evidence that DAH 7-P synthase (phe) catalyzes the si face addition of the C3 of PEP to the re face of C1 of the phosphorylated monosaccharides tested. Products formed by DAH 7-P synthase (phe)-catalyzed condensation of (Z)- and (E)-[3-F]-PEP with E 4-P were completely characterized by (1)H and (19)F NMR analysis for the first time.

Substrate ambiguity of 3-deoxy-D-manno-octulosonate 8-phosphate synthase from Neisseria gonorrhoeae revisited.

Homogeneous, recombinant 3-deoxy-D-manno-octulosonate 8-phosphate synthase from Neisseria gonorrhoeae is shown to catalyze the formation of 3-deoxy-D-manno-octulosonate 8-phosphate from phosphoenolpyruvate and D-arabinose 5-phosphate as determined from (1)H-nuclear magnetic resonance analysis of the product. This enzyme does not catalyze the condensation of D-erythrose 4-phosphate and phosphoenolpyruvate to form 3-deoxy-D-ribo-heptulosonate 7-phosphate, as was previously reported (P. S.

NMR studies of retinoid-protein interactions: the conformation of [13C]-beta-ionones bound to beta-lactoglobulin B.

Purpose: Vitamin A (retinol) and its metabolites comprise the natural retinoids. While the biological action of these molecules are thought to be primarily mediated by ca. 55 kDa nuclear retinoic acid receptors, a number of structurally similar 15-20 kDa proteins are involved in the transport, and possibly metabolism, of these compounds.

Probing the potential metal binding site in Escherichia coli 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (phenylalanine-sensitive).

The active site residues of the proposed metal binding site of DAH 7-P synthase (phe) were probed by site-directed mutagenesis of C61 to glycine and serine, H64 to glycine, and with the double mutant C61H/H64C. While C61S and C61H/ H64C were inactive, both C61G and H64G were active. All mutants, regardless of enzymatic activity, bound one equivalent of Fe2+ per monomeric unit.

Categorization and modeling of information work for H-journal design.

This paper reports on a doctoral research project that examined the work of reference librarians in the health sciences domain. Categories of information work are derived and used to build Hyper-MedLib, a proof-of-concept h-journal. Findings from this study may be used in the design of electronic documents and information systems for the practice environments.

An unnatural biopolymer.

A highly efficient method has been developed for the solid-phase synthesis of an "unnatural biopolymer" consisting of chiral aminocarbonate monomers linked via a carbamate backbone. Oligocarbamates were synthesized from N-protected p-nitrophenyl carbonate monomers, substituted with a variety of side chains, with greater than 99 percent overall coupling efficiencies per step. A spatially defined library of oligocarbamates was generated by using photochemical methods and screened for binding affinity to a monoclonal antibody.

Effect of bed time intermediate acting insulin in NIDDM subjects refractory to a combination of sulphonylureas and biguanides.

The effect of a single dose of intermediate acting (Lente) insulin given subcutaneously at 9.00 P.M.

Subcutaneous insulin pulse therapy.

Subcutaneous Insulin Pulse Therapy (SIPT) consists of administration of small doses of regular insulin hourly or two hourly in the subcutaneous tissue of anterior abdominal wall through a scalp vein needle. Fifteen Non-Insulin Dependent Diabetes Mellitus (NIDDM) subjects, 8 males and 7 females with mean ages 58 +/- 8.7 years and mean duration of diabetes 11.

Keloids and diabetes in a family.

An interesting familial association of keloids with diabetes mellitus in three successive generations is reported. Keloids did not develop if the injection site was changed to the anterior abdominal wall.

Influence of surfactants and polymeric adjuvants on physicochemical properties, droplet size spectra and deposition of fenitrothion and Bacillus thuringiensis formulations under laboratory conditions.

The effect of two surfactants and two polymeric adjuvants on droplet size spectra and deposition patterns of nine spray formulations was investigated following atomization in a laboratory chamber using a spinning disc atomizer that can produce a narrow droplet size spectrum. Spray droplets were sampled using Kromekote cards and deposit recoveries were examined on glass plates. Physicochemical properties studied were: viscosity-shear rate relationship, surface tension, volatility, pH, conductance, electrophoretic mobility and zeta potential.

Influence of adjuvants on physicochemical properties, droplet size spectra and deposit patterns: relevance in pesticide applications.

The influence of adjuvants on physicochemical properties, droplet size spectra and deposit patterns of five aqueous spray mixtures was studied under laboratory conditions, using two surfactants, Atlox 3409F and Triton X-114; two humectants, propylene glycol and glycerol; and one polymeric adjuvant, Agrisol FL-100F. For the sake of comparison, two fenitrothion formulations containing polymeric adjuvants, and water were also included in the study. Spray was applied at 25 degrees C and 75 +/- 5% relative humidity, in an enclosure using a twin fluid atomizer.

Influence of formulation properties on droplet spectra and soil residues of aminocarb aerial sprays in conifer forests.

The influence of formulation properties on spray droplet spectra and soil residues was studied in conifer forests in New Brunswick following aerial application of two oil-based aminocarb formulations of variable viscosities and volatilities. For a given volume rate of application, the formulation of low viscosity and high volatility provided a spectrum of small droplets and a low volume deposit on ground cards. For the same volume rate, the nonvolatile formulation of high viscosity provided a spectrum of larger droplets and consequently a higher volume deposit.

Subchronic toxicity of photomirex in the female rat: results of 28- and 90-day feeding studies.

Photomirex (8-monohydromirex) was administered to female Sprague-Dawley rats at dietary levels of 0.2, 1.0, 5.