Quality control system for mass screening in Japan.

Japan was the first country to establish a nationwide quality control system. When the Japanese Federal Government initiated Nationwide Neonatal Screening in 1977, the system officially included a Quality Control (QC) System that should cover all screening laboratories in Japan. This QC system is quite different from that for usual clinical chemistry. The aim of the National QC System for Neonatal Screening is evaluation of the accuracy of the tests and evaluation of the ability to detect suspicious samples with very mild abnormalities. For accomplishing the aim, the QC center established an inter-laboratory QC survey Screening laboratories having weak points can be identified through the inter-laboratory QC survey, and the Center must find a way to improve the ability of these screening laboratories. This requires a nationwide consensus regarding the cut-off levels of tested materials. Based on the cooperation of the Societies For Mass-screening, of Inborn Errors of Metabolism and of Pediatric Endocrinology, we set low cutoff levels for each compound to minimize the number of false negative cases. The system also included the evaluation of the quality of essential screening reagents and the special filter paper for blood collection (in partnership with the production companies). For this purpose, we developed some new methods for evaluating the standard-compounds for the various screening tests exactly, except in the case of TSH screening.

Isolation and possible composition of glucosylceramides from Paracoccidioides brasiliensis

Twelve different species of neutral monohexosyl ceramides (CMHs) and two species of neutral monohexosyl ceramides were isolated form mycelium and yeast forms of Paracoccidioides brasiliensis, respectively, by a combination of ion-exchange chromatography, HPLC, and HPTLC. The glucosylceramides did not react with sera from patients with paracoccidioidomycosis (PCM). Carbohydrate analysis indicated that CMHs contain glucose. Analysis of (1)H-NMR and mass spectrometry data suggest that the structure of the CMHs is Glcpbeta1(Cer (mycelium forms present 12 different ceramides and yeast forms present 2 different ceramides). The composition of the lipid moieties was analyzed by negative fast atom bombardment mass spectrometry. No glycosphingolipid other than glucosylceramide was detected in P. brasiliensis.

Immunochemical characterization of carbohydrate antigens from fungi, protozoa and mammals by monoclonal antibodies directed to glycan epitopes

Cell surface carbohydrates constitute the major antigenic determinants of fungi and protozoa. Glycoconjugates also represent a large variety of antigens or markers present in mammals such as histo-blood groups ABO, differentiation and heterophile antigens, among others. This article focuses on the general properties of glycoconjugate antigens and production and characterization of the anti-carbohydrate monoclonal antibodies (MoAbs). It describes the specificity and some properties of monoclonal antibodies directed against carbohydrate epitopes present in tumor-associated glycoproteins, in clycosaminoglycans of higher eukaryotes and in glycolipid antigens of protozoa and fungi. The epitopes recognized by the anti-carbohydrate MoAbs range from one sugar unit up to ten sugar units. Although most anti-carbohydrate MoAbs are directed predominantly toward terminal sugar residues, a few MoAbs are also reactive with internal sugar residues. The fine structure of the carbohydrate epitopes has been chemically defined by [H]NMR, GC/MS of alditol acetates of partially permethylated compounds, FAB/MS, degradation with exoglycosidases and inhibition with different methyl-glycosides and oligosaccharides.