Fast sequencing of oligosaccharides: the reagent-array analysis method.

A method of oligosaccharide analysis involving controlled fragmentation resulting from enzymatic digestion is presented. The principle involves generating a set of fragments from the original oligosaccharides, characterizing them in terms of their hydrodynamic volumes, determining their molar proportions, and identifying the oligosaccharides by comparison with a computer-generated data base. Experimentally, this technique involves incubation of aliquots of a sample with a set of defined mixtures of exoglycosidases followed by pooling of the products and a single analysis on the product pool. This method has several practical advantages over current techniques, including speed and the ability to use smaller amounts of starting material. The detection of the intensity-versus-hydrodynamic volume profile is limited only by the specific activity of the labeling method. The ability to perform the enzyme digestions is limited by the individual Km values of the enzymes.     

Stomach cancer in patients under 40

Fifty-one patients below the age of forty were treated for stomach carcinoma at the Surgical Hospital of Mainz University, between 1970 and 1986. They accounted for 5.2 per cent of all patients with stomach carcinoma. Diagnosis had been delayed under the following characteristic circumstances: The interval between onset of symptoms and diagnosis had been more than a year in 34 per cent of all cases. Fifty per cent of the patients had been originally hospitalised, following false suspicious diagnosis. Primary examination for gastro-intestinal passage produced falsely negative results in 43 per cent. The same falsely negative outcome was recorded from 24 per cent, following gastroscopy, and from twelve per cent, following gastroscopy combined with tissue sampling. The percentage of early stomach carcinomas was twice as high as that recorded from patients over forty. Undifferentiated carcinomas, on the other hand, were predominant in patients below forty, whereas adenocarcinomas were primarily recorded from patients over forty. Curative resection was successful in 55 per cent of the over-forties and 44 per cent of the under-forties. No-recurrence intervals were longer among the over-forties. However, five-year survival rates in Stages I, II, and III were better among the under-forties. Hence, the conclusion has been drawn from these findings that stomach carcinoma prognosis of patients below forty is better than that in higher age groups. This, however, is contradictory to other investigations reported in the literature.     

Aza-, Di- und Triazaxanthone aus Azachromonen

Aza-, Di- and Triazaxanthones from Azachromones The acyl(methylthio)azachromones 7a and 7b , which are obtained from the pyridyl-substituted 1,3-dicarbonyl compounds 5a and 5b , react with amines, hydrazine compounds, amidine or CH-acidic compounds to yield the azaxanthones 8a, 8b, 9a and 9b, 11a and 11b , or 13 and 14 .     

Xanthone aus Chromon-Derivaten

Xanthones from Chromone Derivatives The 3-acyl-2-(methylthio)chromones 2a - 2c and the 6-acetyl-7-(methylthio)furochromone 10 react with the CH-acidic compounds 5a-5f, 11 and potassium tert.-butylate to yield the 3-acylchromones 4a - 4d and 9 , the xanthones 1 und 6a - 6d and the furoxanthones 13a-13c and 20 . With ammonium acetate, 4b and 4c gave the benzopyranopyridinones (azaxanthones) 8a - 8b .     

In a pig model ePTFE grafts will sustain for 6 weeks a confluent endothelial cell layer formed in vitro under shear stress conditions.

OBJECTIVE: to investigate in a pig model whether small diameter ePTFE grafts will sustain a confluent endothelial cell layer formed in vitro under shear stress conditions. MATERIALS AND METHODS: thirteen ePTFE (4 mm) grafts were implanted end to end in the right femoral artery of; 8 grafts had been endothelialized in vitro. Grafts were left in situ for 6 weeks then evaluated with ultrasound and histology. RESULTS: seven endothelialized graft were patent with confluent endothelial cell lining. None of the control grafts were patent or showed evidence of an endothelial lining. CONCLUSION: in this pig model ePTFE grafts sustained for 6 weeks a confluent endothelial cell layer formed in vitro under shear stress.     

The role of IgG glycoforms in the pathogenesis of rheumatoid arthritis

Conclusions In conclusion, there is a shift in the population of IgG glycoforms towards those with a higher content of agalactosyl biantennary N-linked oligosaccharides in active rheumatoid arthritis (both juvenile and adult), tuberculosis, and Crohn's disease, but not in a variety of other rheumatological, inflammatory, or infectious conditions. This shift may contribute to disease pathogenesis both through immune-complex formation and through disturbance of a cellular network directed against the non-reducing terminal G1cNAc epitope. The precise pathology would in each case be modulated by the anatomical site(s) of production of such IgG, and also by the precise mechanism inducing this change in IgG glycosylation. Important amongst such mechanisms may be cross-reactivity between environmental and endogenous carbohydrate epitopes. It will be interesting to see if future research supports the idea that groups of diseases (e. g., rheumatoid arthritis, tuberculosis, Crohn's) are indeed related by a common aetiopathogenesis [i. e., G(0)].     

Practical and technical considerations in establishing an intraoperative radiation therapy program in the community practice

The Radiation Oncology Center in Sacramento, California, has developed a procedure for establishing an intraoperative radiation therapy facility in a community practice. The logistics pertaining to personnel, equipment, physical measurements, and quality assurance are presented. Particular emphasis is given to the most effective means of acquiring the large quantity of data needed to ensure a program of acceptable quality.