Ear wax and otitis media in children.

A study was designed to find the prevalence of ear wax in children aged 3 to 10 years and to test the belief that large amounts of wax are unlikely to be seen when otitis media is present. Roughly a quarter of the children had appreciable amounts of wax, and there was a gradual decline in prevalence with age. The amount of ear wax appeared to decrease when otitis media was present. The results did not support removing wax when assessing children''s ears in general practice.     

Regulation of beta-1, 4-Glucosidase Expression by Candida wickerhamii

Candida wickerhamii NRRL Y-2563 expressed beta-glucosidase activity (3 to 8 U/ml) constitutively when grown aerobically in complex medium containing either glycerol, succinate, xylose, galactose, or cellobiose as the carbon source. The addition of a high concentration of glucose (>75 g/liter) repressed beta-glucosidase expression (<0.3 U/ml); however, this yeast did produce beta-glucosidase when the initial glucose concentration was 相似文献   

Direct fermentation of cellodextrins to ethanol byCandida wickerhamii andC. Lusitaniae

Summary Production of ethanol from cellodextrins, as large as cellohexose, byCandida lusitaniae andC. wickerhamii was studied.C. lusitaniae fermented only glucose and cellobiose, whereasC. wickerhamii efficiently fermented cellodextrins. Maximum ethanol yields of 29.2 g/liter from 54 g/liter cellodextrins were achieved byC. wickerhamii in 3–4 days.     

X-ray crystallographic study of boronic acid adducts with subtilisin BPN' (Novo). A model for the catalytic transition state.

We have studied the structures of adducts formed between subtilisin BPN' and both benzeneboronic acid and 2-phenylethaneboronic acid by x-ray diffraction techniques. Electron density and difference maps at 2.5 A resolution were computed with phases calculated from a partially refined structure of the native enzyme (R = 0.23 at 2.0 A). Both adducts contain a covalent bond between Ogamma of the catalytic Ser-221 and the inhibitor boron atom. The boron atom is coordinated tetrahedrally, with one of the two additional boronic acid oxygen atoms lying in the "oxyanion hole" and the other at the leaving group site identified in previous studies (ROBERTUS, J.D., Kraut, J. ALDEN, R.A., and BIRKTOFT, J.J. (1972) Biochemistry 11, 4293-4303). Moreover, the previously postulated structure of the tetrahedral intermediate for substrate hydrolysis is isosteric with these boronic acid adducts, which can therefore be considered good models for the transition state complex (KOEHLER, K.K., and LIENHARD, G.E. (1972) Biochemistry 10, 2477-2483). These observations further support the suggestion that an important contribution to stabilization of this transition state complex, relative to both the Michaelis complex and the acyl intermediate, occurs as a consequence of hydrogen bond donation to the substrate carbonyl oxygen atom from the side chain amido group of Asn-155 and from the backbone amido group of Ser-221.     

Biomarker of food intake for assessing the consumption of dairy and egg products

Dairy and egg products constitute an important part of Western diets as they represent an excellent source of high-quality proteins, vitamins, minerals and fats. Dairy and egg products are highly diverse and their associations with a range of nutritional and health outcomes are therefore heterogeneous. Such associations are also often weak or debated due to the difficulty in establishing correct assessments of dietary intake. Therefore, in order to better characterize associations between the consumption of these foods and health outcomes, it is important to identify reliable biomarkers of their intake. Biomarkers of food intake (BFIs) provide an accurate measure of intake, which is independent of the memory and sincerity of the subjects as well as of their knowledge about the consumed foods. We have, therefore, conducted a systematic search of the scientific literature to evaluate the current status of potential BFIs for dairy products and BFIs for egg products commonly consumed in Europe. Strikingly, only a limited number of compounds have been reported as markers for the intake of these products and none of them have been sufficiently validated. A series of challenges hinders the identification and validation of BFI for dairy and egg products, in particular, the heterogeneous composition of these foods and the lack of specificity of the markers identified so far. Further studies are, therefore, necessary to validate these compounds and to discover new candidate BFIs. Untargeted metabolomic strategies may allow the identification of novel biomarkers, which, when taken separately or in combination, could be used to assess the intake of dairy and egg products.