Serotyping of Streptococcus pneumoniae by coagglutination with 12 pooled antisera

We report on the performance of a recently introduced commercial chessboard method using 12 antisera, in comparison with that of the 55-antiserum panel used in determining the serogroups and types (SGTs) of Streptococcus pneumoniae, both of which were carried out by a coagglutination technique. Of a total of 150 strains of S. pneumoniae studied, 135 (90%) belonged to the SGTs represented in the 23-valent pneumococcal vaccine; of these, 130 (96.3%) were identified as the same SGTs by both typing methods. The remaining five strains showed cross-reactivity with more than two pools by the chessboard method, but could be assigned to a single SGT by the Quellung test. The 96.3% concordance of the chessboard method suggests it can be adopted for determination of the SGTs of S. pneumoniae in laboratories.     

Treating fluid noncompliance in the hemodialysis population using unit wide contests

Thirty-six patients with tinea unguium were treated with 200 mg of itraconazole daily for 7 days each month. We suggested that a patient who had a lesion in the thumbnail needed 5 months of treatment for mycologial cure, while in a patient without thumbnail lesion, 3 months of treatment was enough.     

Characterization of the interactions between human cdc25C, cdks, cyclins and cdk-cyclin complexes

We have overexpressed and purified human dual-specificity phosphatase cdc25C from a prokaryotic expression system at high levels and in a soluble, active form, and have studied and quantified its potential to interact with cdks, cyclins and preformed cdk-cyclin complexes by fluorescence spectroscopy and size-exclusion chromatography. Our data indicate that human cdc25C forms stable complexes, through hydrophobic contacts, with cdk and cyclin monomers, as well as with preformed cdk-cyclin complexes. In vitro, cdc25C interacts with cyclin monomers with high affinity, with tenfold less affinity with cdks, and with intermediate affinity with cdk-cyclin complexes. Moreover, changes observed in the intrinsic fluorescence of cdks, cyclins and cdk-cyclin complexes upon interaction with cdc25C are indicative of concomitant conformational changes within cdks and cyclins. From our results, we propose that in vitro, in the presence of monomeric cdks and cyclins, cdc25C forms stable ternary complexes, first through a high affinity interaction with a cyclin, which may then help target cdc25C towards a cdk. We discuss the biological relevance of our results and propose that a similar, two-step mechanism of interaction between cdc25C and cdk-cyclin complexes may occur in vivo.     

Unrelated donor bone marrow transplantation for chronic myelogenous leukemia: a decision analysis

BACKGROUND: Chronic myelogenous leukemia (CML) is an indolent but ultimately fatal disease. Because the natural history of CML varies and quality of life with CML may be excellent until shortly before death, deciding whether and when to pursue unrelated donor bone marrow transplantation is often difficult. OBJECTIVE: To compare early transplantation, delayed transplantation, and no transplantation for patients with chronic-phase CML on the basis of discounted, quality-adjusted life expectancy. DESIGN: A markov model comparing different strategies was constructed. This model considers patient age, quality of life, risk aversion, and the competing risks for CML progression and transplant toxicity. SETTING: Therapeutic decision at the time of diagnosis of CML. PATIENTS: The base case is a 35-year-old patient with intermediate-prognosis CML. Younger and older patients with better and worse prognoses are also evaluated. INTERVENTION: Early transplantation, delayed transplantation, and no transplantation. MEASUREMENTS: Quality-adjusted, discounted life expectancy. RESULTS: For patients with newly diagnosed CML, transplantation within the first year provides the greatest quality-adjusted expected survival, although this benefit decreases with increasing patient age. For a 35-year-old patient with intermediate-prognosis CML, transplantation within the first year results in 53 more discounted, quality-adjusted years of life expectancy than does no transplantation. This finding is robust even with varying baseline assumptions. CONCLUSIONS: These results support the use of early unrelated donor bone marrow transplantation for most patients with CML.     

Phosphorescence quenching method for measurement of intracellular PO2 in isolated skeletal muscle fibers

Values of skeletal muscle intracellular PO2 during conditions ranging from rest to maximal metabolic rates have been difficult to quantify. A method for measurement of intracellular PO2 in isolated single skeletal muscle fibers by using O2-dependent quenching of a phosphorescent-O2 probe is described. Intact single skeletal muscle fibers from Xenopus laevis were dissected from the lumbrical muscle and mounted in a glass chamber containing Ringer solution at 20 degreesC. The chamber was placed on the stage of an inverted microscope configured for epi-illumination. A solution containing palladium-meso-tetra (4-carboxyphenyl) porphine bound to bovine serum albumin was injected into single fibers by micropipette pressure injection. Phosphorescence-decay curves (average of 10 rapid flashes) were recorded every 7 s from single cells (n = 24) in which respiration had been eliminated with NaCN, while the PO2 of the Ringer solution surrounding the cell was varied from 0 to 159 Torr. For each measurement, the phosphorescence lifetime was calculated at the varied extracellular PO2 by obtaining a best-fit estimate by using a monoexponential function. The phosphorescence lifetime varied from 40 to 70 microseconds at an extracellular PO2 of 159 Torr to 650-700 microseconds at 0 Torr. The phosphorescent lifetimes for the varied PO2 were used to calculate, by using the Stern-Volmer relationship, the phosphorescence-quenching constant (100 Torr-1. s-1), and the phosphorescence lifetime in a zero-O2 environment (690 microseconds) for the phosphor within the intracellular environment. This technique demonstrates a novel method for determining intracellular PO2 in isolated single skeletal muscle fibers.     

A conserved LIM protein that affects muscular adherens junction integrity and mechanosensory function in Caenorhabditis elegans

The glycosylation of the equine interhaemal barrier and areola was studied throughout the period of gestation. Placentae of 35, 37, 50, 119, 152, 200, 280 and 300 days gestation were investigated, using semithin plastic embedded sections and a panel of 15 biotinylated lectins with an avidin-peroxidase revealing system. Glycosylation of the trophoblast and maternal epithelium showed the most change during the first 50 days of gestation, being associated with the initial stages of adhesion and attachment. In the trophoblast, non-bisected tri/tetraantennary complex N-glycan was only evident after day 37 and terminal N-acetyl galactosamine, alpha2,3- and alpha2,6-linked sialic acids disappeared at the same time. The areolar trophoblast exhibited some differences from microcotyledonary areas, especially with respect to 2-deoxy, 2-acetamido alpha-galactose and tri/tetraantennary, non-bisected complex N-glycan, suggesting that the differences in function between microcotyledonary and areolar trophoblast are reflected at both the morphological and the biochemical level. Granules of the maternal uterine epithelium bound many lectins, particularly those with specificity for bisected and non-bisected bi/triantennary N-linked glycan, 2-deoxy, 2-acetamido alpha-galactosyl, beta-galactosyl and some fucosylated termini. Binding to sialic acids in alpha2,3- and alpha2,6-linkage was sparse. Maternal and fetal capillaries showed little change in glycan expression over the period studied, being rich in bisected and non-bisected bi/triantennary N-linked glycan and sialic acids, with some terminal N-acetyl galactosamine and no detectable terminal fucosyl residues.     

Biased TCR repertoire in infiltrating lesional T cells in human Bancroftian filariasis

To investigate the hypothesis that T cells recognizing specific Ags localize to the site of disease activity in human bancroftian filariasis, we have compared the repertoire of TCR Vbeta gene segments in lesions vs blood in individual patients by RT-PCR ELISA. Vbeta14 and Vbeta24 were overrepresented (5% greater in tissue compared with PBMCs and/or tissue/PBMC ratios in the highest 5% of all tissue/PBMC ratios for all Vbetas for all subjects) in 50% and 40% of study subjects, respectively. Overrepresentation of these two Vbetas did not occur in any control subject. In comparing three patient groups, the proportion of individuals meeting at least one criterion for Vbeta14 overrepresentation was shown to increase in tandem with our current concepts of disease progression (asymptomatic filariasis = 25%; clinical filariasis with active infection = 60%; clinical filariasis without active infection = 71%). In 6 of the 10 individuals with Vbeta14 overrepresentation, Vbeta14 represented >20% of the entire lesional Vbeta repertoire. All but one of the 20 study subjects had at least one Vbeta gene segment that was overrepresented in tissue compared with PBMCs. Only a small number of Vbetas, usually three or less, were overrepresented in any single filariasis patient. However, in the same tissue, no differences between patient groups were found when IFN-gamma, TNF-alpha, IL-4, IL-5, and IL-12 mRNA expression were examined. Taken together, these findings suggest that, in principle, in essentially all patients, whether with subclinical or with clinical filariasis, distinct and limited T cell populations are concentrated in affected tissue.     

Linkage of proximal myotonic myopathy to chromosome 3q

We performed genetic linkage analysis in nine German proximal myotonic myopathy (PROMM) families using DNA-markers D3S1541 and D3S1589 from the region of the recently discovered gene locus of myotonic dystrophy type 2 (DM2) on chromosome 3q. Two-point analysis supplied an lod score of 5.9. We conclude that a gene causing PROMM is located on chromosome 3q. PROMM and DM2 may be allelic disorders or may be caused by closely linked genes.